Tomographic X-ray apparatus for the production of transverse layer images

Claim 2

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including an X-ray source which produces a beam of X-ray energy for penetrating a patient transverse layer, and radiation measurement means arranged in a common transverse plane with said X-ray source, and receiving the X-ray energy of the beam after transmission through a patient transverse layer lying in said common transverse plane so as to provide an output comprising a set of individual measurement signals as a measure of the radiation intensity of the transmitted beam over the transverse extent of the patient transverse layer, (c) tomographic angular scanning means coupled with the X-ray source operable in a tomographic angular scanning mode for producing rotational movements of said X-ray source in said common transverse plane through a wide range of angular relationships relative to said patient transverse layer so as to generate a sufficient number of sets of individual measurement signals to define a tomographic layer image of the patient transverse layer, (d) longitudinal drive means operating in a shadow image generating mode for producing relative longitudinal movement between the measuring arrangement and the patient support in the longitudinal direction of the latter, (e) control means operating in said shadow image generating mode during relative longitudinal movement of said patient support through successive longitudinal positions and controlling said X-ray source, (f) computer means operating in the shadow image generating mode for the storage of an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of longitudinal movement produced by said longitudinal drive means during operation in said shadow image generating mode, and operating in said tomographic angular scanning mode for computing a tomographic layer image of the patient transverse layer based on the sets of individual measurement signals generated during operation of said tomographic angular scanning means, (g) measured value sampling means responsive to said control means and operable in said shadow image generating mode for effecting ony one sampling of the output from said radiation measurement means for each of said successive longitudinal positions and for supplying respective sets of shadow image measurement signals based on the respective samplings of the output of said radiation measurement means, to said computer means for storage thereby, and (h) video display means connectable with said computer means and operating in a shadow image display mode for displaying the respective sets of shadow image measurement signals as successive lines of a video image, (i) said control means operating in said shadow image generating mode to intermittently turn on the beam of X-ray energy from said X-ray source with the frequency of the turning on of said beam being correlated with the rate of operation of said longitudinal drive means such that only an X-ray shadow image is generated during said shadow image mode with the patient being scanned by the beam of X-ray energy from only a single angular relationship relative to the patient support.

Claim 3

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including an X-ray source which produces a beam of X-ray energy for penetrating a patient transverse layer at a transverse plane, and radiation measurement means arranged to receive the X-ray energy of the beam after transmission through the patient transverse layer so that the radiation measurement means provides a set of measurement readings which are measures of the radiation intensity of the transmitted beam over the transverse extent of the patient transverse layer, (c) tomographic angular scanning means coupled with the X-ray source and operable in a tomographic angular scanning mode for producing rotational movements of the X-ray source in said transverse plane through a wide range of angular relationships relative to the patient transverse layer so as to generate a sufficient number of sets of measurement readings to define a tomographic layer image of the patient transverse layer, (d) longitudinal drive means operable in a shadow image generating mode for producing longitudinal movement of the patient support in the longitudinal direction of the latter, (e) control means operating in said shadow image generating mode for producing successive pulses of X-ray energy from said X-ray source during longitudinal movement of said patient support through successive longitudinal positions while the measuring arrangement is in a single angular relationship to said patient support, and (f) shadow image storage means operating in said shadow image generating mode for the storage of a set of measurement readings from the radiation measurement means in each of the successive longitudinal positions of said patient support for defining an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of longitudinal movement produced by said longitudinal drive means during operation in said shadow image generating mode, and (g) measured value processing means controlled by said control means and operating in said shadow image generating mode for transmitting only the readings defining said X-ray shadow image to said shadow image storage means, (h) said control means operating in said shadow image generating mode for producing a pulse of X-ray energy from said X-ray source and for actuating said measured value processing means to transmit the set of measurement readings from the radiation receiver produced by such pulse to said shadow image storage means, for each of the successive longitudinal positions of the patient support, said control means producing the pulses of X-ray energy with a frequency correlated with the rate of longitudinal movement of said patient support during said shadow image generating mode so as to provide a predetermined positional resolution in said longitudinal direction.

Claim 4

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including an X-ray source which produces a beam of X-ray energy for penetrating a patient transverse layer at a transverse plane, and radiation measurement means arranged to receive the X-ray energy of the beam after transmission through the patient transverse layer so that the radiation measurement means provides a set of measurement readings which are measures of the radiation intensity of the transmitted beam over the transverse extent of the patient transverse layer, (c) tomographic angular scanning means coupled with the X-ray source and operable in a tomographic angular scanning mode for producing rotational movements of the X-ray source in said transverse plane through a wide range of angular relationships relative to the patient transverse layer so as to generate a sufficient number of sets of measurement readings to define a tomographic layer image of the patient transverse layer, (d) longitudinal drive means operable in a shadow image generating mode for producing longitudinal movement of the patient support in the longitudinal direction of the latter, (e) control means operating in said shadow image generating mode for producing successive pulses of X-ray energy from said X-ray source during longitudinal movement of said patient support through successive longitudinal positions while the measuring arrangement is in a single angular relationship to said patient support, and (f) shadow image storage means operating in said shadow image generating mode for the storage of a set of measurement readings from the radiation measurement means in each of the successive longitudinal positions of said patient support for defining an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of longitudinal movement produced by said longitudinal drive means during operation in said shadow image generating mode, and (g) measured value processing means controlled by said control means and operating in said shadow image generating mode for transmitting only the readings defining said X-ray shadow image to said shadow image storage means, (h) said control means operating in said shadow image generating mode for producing a pulse of X-ray energy from said X-ray source and for actuating said measured value processing means to transmit the set of measurement readings from the radiation receiver produced by such pulse to said shadow image storage means, for each of the successive longitudinal positions of the patient support, said control means producing the pulses of X-ray energy with a frequency correlated with the rate of longitudinal movement of said patient support during said shadow image generating mode so as to provide a predetermined positional resolution in said longitudinal direction.

Claim 5

Tomographic apparatus according to claim 2, with said radiation measurement means providing a predetermined transverse image resolution, and said control means producing pulses of X-ray energy during operation in said shadowgraphic mode such as to provide a predetermined positional resolution in said longitudinal direction substantially corresponding to the predetermined transverse image resolution provided by said radiation measurement means.

Claim 6

Tomographic apparatus according to claim 3, with said control means automatically correlating the frequency of the successive pulses of X-ray energy with the rate of longitudinal movement of said patient support so as to provide said predetermined positional resolution in said longitudinal direction.

Claim 7

Tomographic apparatus for the production of transverse-layer images of an exposed subject, comprising a patient's support, an X-ray measuring arrangement, including an X-ray source which produces a beam of X-ray energy for penetrating the exposed subject with respect to a transverse plane, and a radiation receiver which provides readings which are measures of the radiation intensity of the transmitted beam, scanning means coupled with the source for producing rotational movements through a wide range of angular relationships so as to generate a sufficient number of sets of readings to define a tomographic layer image, longitudinal drive means for producing relative longitudinal movement between the measuring arrangement and the patient's support in the longitudinal direction of the latter during storage of the readings from the radiation receiver, control means coupled with the longitudinal drive means and operable in an automatic shadow image generating mode for automatically producing longitudinal movement of said patient support through successive longitudinal positions while the measuring arrangement is locked in a single angular relationship, shadow image storage means operable for the storage of only one set of readings from the radiation receiver in each of the successive positions of said patient support for defining an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of longitudinal movement produced by said longitudinal drive means during automatic operation of said control means in said automatic shadow image generating mode, said shadow image storage means having sequentially accessible sets of storage positions each for storing only one set of readings from said radiation receiver, and means responsive to said control means and automatically operable in said automatic shadow image generating mode for transmitting only one set of readings from said radiation receiver to said sequentially accessible sets of storage positions of said shadow image storage means for each of said successive longitudinal positions, and for storing at the respective sequentially accessible sets of storage positions the respective sets of readings taken in the successive longitudinal positions, such that sequential read out of said sets of sequentially accessible storage positions generates an X-ray shadow image of the patient over said longitudinal extent of the successive longitudinal positions.

Claim 8

Tomographic apparatus for the production of transverse-layer images of an exposed subject, comprising a patient's support, an X-ray measuring arrangement, including an X-ray source which produces a beam of X-ray energy for penetrating the exposed subject with respect to a transverse plane, and a radiation receiver which provides readings which are measures of the radiation intensity of the transmitted beam, scanning means coupled with the source for producing rotational movements through a wide range of angular relationships so as to generate a sufficient number of sets of readings to define a tomographic layer image, longitudinal drive means for producing relative longitudinal movement between the measuring arrangement and the patient's support in the longitudinal direction of the latter during storage of the readings from the radiation receiver, control means coupled with the longitudinal drive means and operable in an automatic shadow image generating mode for automatically producing longitudinal movement of said patient support through successive longitudinal positions while the measuring arrangement is locked in a single angular relationship, shadow image storage means operable for the storage of only one set of readings from the radiation receiver in each of the successive positions of said patient support for defining an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of longitudinal movement produced by said longitudinal drive means during automatic operation of said control means in said automatic shadow image generating mode, said shadow image storage means having sequentially accessible sets of storage positions each for storing only one set of readings from said radiation receiver, and means responsive to said control means and automatically operable in said automatic shadow image generating mode for transmitting only one set of readings from said radiation receiver to said sequentially accessible sets of storage positions of said shadow image storage means for each of said successive longitudinal positions, and for storing at the respective sequentially accessible sets of storage positions the respective sets of readings taken in the successive longitudinal positions, such that sequential read out of said sets of sequentially accessible storage positions generates an X-ray shadow image of the patient over said longitudinal extent of the successive longitudinal positions.

Claim 9

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including an X-ray source which produces a fan-shaped beam of X-ray energy for penetrating a patient transverse layer at a transverse plane, and a radiation receiver in said transverse plane which provides readings which are measures of the radiation intensity of the transmitted fan-shaped beam, (c) scanning means coupled with the X-ray source for producing rotational movements of said fan-shaped beam in said transverse plane through a wide range of angular relationships relative to the patient transverse layer so as to generate a sufficient number of sets of readings to define a tomographic layer image of the patient transverse layer, (d) longitudinal drive means operable in a shadow image generating mode for producing relative longitudinal movement between the measuring arrangement and the patient support in the longitudinal direction of the latter during storage of the readings from the radiation receiver, (e) control means coupled with the longitudinal drive means and operable in said shadow image generating mode for supplying turn-on pulses for intermittently turning on said X-ray source such that the X-ray source is pulsed during the relative longitudinal movement of said patient support through successive longitudinal positions while the X-ray source is locked in a single angular relationship, and (f) shadow image storage means operable in said shadow image generating mode for the storage of only one set of readings from the radiation receiver in each of the successive longitudinal positions for defining an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of relative longitudinal movement produced by said longitudinal drive means during operation of said control means in said shadow image generating mode, (g) said control means comprising sequence timer means operable in said shadow image generating mode for correlating the frequency of the turn-on pulses supplied to effect the intermittent turning on of the X-ray source with the speed of operation of the longitudinal drive means in producing said relative longitudinal movement while the X-ray source is locked in said single angular relationship such that said X-ray source is pulsed only at said successive longitudinal positions which define said X-ray shadow image of the patient and such that said X-ray energy penetrates each successive patient region at the transverse plane with only a single angular relationship to such patient region at each of said successive longitudinal positions during the operation of said sequence timer means in said shadow image generator mode.

Claim 10

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including an X-ray source which produces a fan-shaped beam of X-ray energy for penetrating a patient transverse layer at a transverse plane, and a radiation receiver in said transverse plane which provides readings which are measures of the radiation intensity of the transmitted fan-shaped beam, (c) scanning means coupled with the X-ray source for producing rotational movements of said fan-shaped beam in said transverse plane through a wide range of angular relationships relative to the patient transverse layer so as to generate a sufficient number of sets of readings to define a tomographic layer image of the patient transverse layer, (d) longitudinal drive means operable in a shadow image generating mode for producing relative longitudinal movement between the measuring arrangement and the patient support in the longitudinal direction of the latter during storage of the readings from the radiation receiver, (e) control means coupled with the longitudinal drive means and operable in said shadow image generating mode for supplying turn-on pulses for intermittently turning on said X-ray source such that the X-ray source is pulsed during the relative longitudinal movement of said patient support through successive longitudinal positions while the X-ray source is locked in a single angular relationship, and (f) shadow image storage means operable in said shadow image generating mode for the storage of only one set of readings from the radiation receiver in each of the successive longitudinal positions for defining an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of relative longitudinal movement produced by said longitudinal drive means during operation of said control means in said shadow image generating mode, (g) said control means comprising sequence timer means operable in said shadow image generating mode for correlating the frequency of the turn-on pulses supplied to effect the intermittent turning on of the X-ray source with the speed of operation of the longitudinal drive means in producing said relative longitudinal movement while the X-ray source is locked in said single angular relationship such that said X-ray source is pulsed only at said successive longitudinal positions which define said X-ray shadow image of the patient and such that said X-ray energy penetrates each successive patient region at the transverse plane with only a single angular relationship to such patient region at each of said successive longitudinal positions during the operation of said sequence timer means in said shadow image generator mode.

Claim 11

Tomographic apparatus according to claim 6, with said sequence timer means supplying said turn-on pulses during operation in said shadow image generating mode with a frequency so correlated with said speed of operation of said longitudinal drive means that the X-ray source is pulsed only at successive longitudinal positions which are separated by one millimeter.

Claim 12

Tomographic apparatus according to claim 6 with said radiation receiver comprising a bank of detectors which are successively offset from each other in a transverse direction for receiving said fan-shaped beam of X-ray energy from said X-ray source, the number of successively offset detectors of said bank providing a transverse image resolution in the transverse direction, said sequence timer means supplying said turn-on pulses during operation in said shadow image generating mode with a frequency so correlated with said speed of operation of said longitudinal drive means that the X-ray source is pulsed only at successive longitudinal positions which are separated by a longitudinal increment substantially corresponding to said transverse image resolution given by said number of successively offset detectors of said bank.

Claim 13

Tomographic apparatus according to claim 6, with said longitudinal drive means comprising stepping motor means which indexes a desired longitudinal increment for each control pulse supplied thereto, said sequence timer means during operation in said shadow image generating mode supplying only one turn-on pulse for turning on said X-ray source to emit one pulse of X-ray energy between the successive indexing movements of said stepping motor means and operating such that after indexing of the stepping motor means to each of said successive longitudinal positions, the X-ray source is turned on by said sequence timer means so as to produce only one X-ray pulse of duration to produce one shadow image exposure, said sequence timer means alternately supplying said turn-on pulses and the control pulses during the storage of the successive sets of readings from said radiation receiver so as to define said X-ray shadow image while throughout the shadow image generating mode the X-ray source remains locked in said single angular relationship.

Claim 14

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including an X-ray source which produces a beam of X-ray energy for penetrating a patient transverse layer at a transverse plane, and a radiation receiver in said transverse plane arranged to receive the X-ray energy of the beam after transmission through the patient transverse layer so that the radiation receiver provides readings which are measures of the radiation intensity of the transmitted beam, (c) tomographic angular scanning means coupled with the X-ray source and operable in a tomographic angular scanning mode for producing rotational movements of the X-ray source in said transverse plane through a wide range of angular relationships relative to the patient transverse layer so as to generate a sufficient number of sets of readings to define a tomographic layer image of the patient transverse layer, (d) longitudinal drive means operable in a shadow image generating mode for producing longitudinal movement of the patient support in the longitudinal direction of the latter, (e) control means coupled with the longitudinal drive means and operable in said shadow image generating mode for producing successive pulses of X-ray energy from said X-ray source during longitudinal movement of said patient support through successive longitudinal positions while the measuring arrangement is locked in a single angular relationship such that the successive pulses of X-ray energy produce successive X-ray beams in the transverse plane and impinging on the radiation receiver which successive X-ray beams in said transverse plane have only a single angular relationship to a patient on the patient support, (f) shadow image storage means operable in said shadow image generating mode for the storage of the readings from the radiation receiver in each of the successive longitudinal positions of said patient support for defining an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of longitudinal movement produced by said longitudinal drive means during operation of said control means in said shadow image generating mode, and (g) measured value processing means responsive to said control means and operable in said shadow image generating mode for transmitting only the readings defining said X-ray shadow image to said shadow image storage means, (h) said control means comprising sequencing means operable in said shadow image generating mode for producing a pulse of X-ray energy from said X-ray source and for actuating said measured value processing means to transmit the readings from the radiation receiver produced by such pulse to said shadow image storage means, for each of the successive longitudinal positions of the patient support, said sequencing means producing the pulses of X-ray energy with a frequency correlated with the speed of operation of said longitudinal drive means during said shadow image generating mode so as to provide a predetermined positional resolution in said longitudinal direction.

Claim 15

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including an X-ray source which produces a beam of X-ray energy for penetrating a patient transverse layer at a transverse plane, and a radiation receiver in said transverse plane arranged to receive the X-ray energy of the beam after transmission through the patient transverse layer so that the radiation receiver provides readings which are measures of the radiation intensity of the transmitted beam, (c) tomographic angular scanning means coupled with the X-ray source and operable in a tomographic angular scanning mode for producing rotational movements of the X-ray source in said transverse plane through a wide range of angular relationships relative to the patient transverse layer so as to generate a sufficient number of sets of readings to define a tomographic layer image of the patient transverse layer, (d) longitudinal drive means operable in a shadow image generating mode for producing longitudinal movement of the patient support in the longitudinal direction of the latter, (e) control means coupled with the longitudinal drive means and operable in said shadow image generating mode for producing successive pulses of X-ray energy from said X-ray source during longitudinal movement of said patient support through successive longitudinal positions while the measuring arrangement is locked in a single angular relationship such that the successive pulses of X-ray energy produce successive X-ray beams in the transverse plane and impinging on the radiation receiver which successive X-ray beams in said transverse plane have only a single angular relationship to a patient on the patient support, (f) shadow image storage means operable in said shadow image generating mode for the storage of the readings from the radiation receiver in each of the successive longitudinal positions of said patient support for defining an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of longitudinal movement produced by said longitudinal drive means during operation of said control means in said shadow image generating mode, and (g) measured value processing means responsive to said control means and operable in said shadow image generating mode for transmitting only the readings defining said X-ray shadow image to said shadow image storage means, (h) said control means comprising sequencing means operable in said shadow image generating mode for producing a pulse of X-ray energy from said X-ray source and for actuating said measured value processing means to transmit the readings from the radiation receiver produced by such pulse to said shadow image storage means, for each of the successive longitudinal positions of the patient support, said sequencing means producing the pulses of X-ray energy with a frequency correlated with the speed of operation of said longitudinal drive means during said shadow image generating mode so as to provide a predetermined positional resolution in said longitudinal direction.

Claim 16

Tomographic apparatus according to claim 10, with said radiation receiver providing a predetermined transverse image resolution, and said sequencing means producing pulses of X-ray energy during operation in said shadowgraphic mode such as to provide a predetermined positional resolution in said longitudinal direction substantially corresponding to the predetermined transverse image resolution provided by said radiation receiver.

Claim 17

Tomographic apparatus according to claim 10, with said measured value processing means being responsive to a pulse from said sequencing means to transmit a sample of suitable duration of the output of the radiation receiver to said shadow image storage means, and said sequencing means transmitting only one pulse to said measured value processing means for each of the successive longitudinal positions of said patient support during operation in said shadow image generating mode.

Claim 18

Tomographic apparatus according to claim 10, with computer means operable in said tomographic angular scanning mode for storing the sets of readings defining a tomographic layer image of the patient transverse layer, and operable in said shadow image generating mode to provide for the storage of only the readings for defining an X-ray shadow image, and switch means for switching the computer means between said tomographic angular scanning mode and said shadow image generating mode.

Claim 19

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including an X-ray source which produces a beam of X-ray energy for penetrating a patient transverse layer, and a radiation receiver arranged in a common transverse plane with said X-ray source, and receiving the X-ray energy of the beam after transmission through a patient transverse layer lying in said common transverse plane so as to provide an output which is a measure of the radiation intensity of the transmitted beam, (c) tomographic angular scanning means coupled with the X-ray source and operable in a tomographic angular scanning mode for producing rotational movements of said X-ray source in said common transverse plane through a wide range of angular relationships relative to said patient transverse layer so as to generate a sufficient number of sets of readings to define a tomographic layer image of the patient transverse layer, (d) longitudinal drive means operable in a shadow image generating mode for producing relative longitudinal movement between the measuring arrangement and the patient support in the longitudinal direction of the latter, (e) control means coupled with the longitudinal drive means and operable in said shadow image generating mode for producing relative longitudinal movement of said patient support through successive longitudinal positions while the measuring arrangement is locked in a single angular relationship, (f) computer means operable in the shadow image generating mode for the storage of an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of longitudinal movement produced by said longitudinal drive means during operation of said control means in said shadow image generating mode, and operable in said tomographic angular scanning mode for computing a tomographic layer image of the patient transverse layer based on the sets of readings generated during operation of said tomographic angular scanning means, (g) measured value sampling means responsive to said control means and operable in said automatic shadow image generating mode for effecting only one sampling of the output from said radiation receiver for each of said successive longitudinal positions and for supplying respective sets of shadow image readings based on the respective samplings of the output of said radiation receiver to said computer means for storage thereby, (h) video display means connectable with said computer means and operable in a shadow image display mode for displaying the respective sets of shadow image readings as successive lines of a video image, and operable in a tomographic layer image display mode for displaying a computed tomographic layer image, (i) said control means being turned on for the duration of said shadow image generating mode and being operable throughout the duration of said shadow image generating mode to supply turn-on pulses to intermittently turn on the X-ray beam from said X-ray source with the frequency of said turn-on pulses being correlated with the speed of operation of said longitudinal drive means such that only an X-ray shadow image is generated during said shadow image mode with the patient being scanned by the X-ray source from only a single angular relationship relative to the patient, and (j) switch means connected with said computer means and with said video display means and operable in one switching condition to supply the respective sets of shadow image readings from the computer means to said video display means for display of the X-ray shadow image,--and operable in a second switching condition to supply the computed tomographic layer image from the computer means to said video display means for display thereby.

Claim 20

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including an X-ray source which produces a beam of X-ray energy for penetrating a patient transverse layer, and a radiation receiver arranged in a common transverse plane with said X-ray source, and receiving the X-ray energy of the beam after transmission through a patient transverse layer lying in said common transverse plane so as to provide an output which is a measure of the radiation intensity of the transmitted beam, (c) tomographic angular scanning means coupled with the X-ray source and operable in a tomographic angular scanning mode for producing rotational movements of said X-ray source in said common transverse plane through a wide range of angular relationships relative to said patient transverse layer so as to generate a sufficient number of sets of readings to define a tomographic layer image of the patient transverse layer, (d) longitudinal drive means operable in a shadow image generating mode for producing relative longitudinal movement between the measuring arrangement and the patient support in the longitudinal direction of the latter, (e) control means coupled with the longitudinal drive means and operable in said shadow image generating mode for producing relative longitudinal movement of said patient support through successive longitudinal positions while the measuring arrangement is locked in a single angular relationship, (f) computer means operable in the shadow image generating mode for the storage of an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of longitudinal movement produced by said longitudinal drive means during operation of said control means in said shadow image generating mode, and operable in said tomographic angular scanning mode for computing a tomographic layer image of the patient transverse layer based on the sets of readings generated during operation of said tomographic angular scanning means, (g) measured value sampling means responsive to said control means and operable in said automatic shadow image generating mode for effecting only one sampling of the output from said radiation receiver for each of said successive longitudinal positions and for supplying respective sets of shadow image readings based on the respective samplings of the output of said radiation receiver to said computer means for storage thereby, (h) video display means connectable with said computer means and operable in a shadow image display mode for displaying the respective sets of shadow image readings as successive lines of a video image, and operable in a tomographic layer image display mode for displaying a computed tomographic layer image, (i) said control means being turned on for the duration of said shadow image generating mode and being operable throughout the duration of said shadow image generating mode to supply turn-on pulses to intermittently turn on the X-ray beam from said X-ray source with the frequency of said turn-on pulses being correlated with the speed of operation of said longitudinal drive means such that only an X-ray shadow image is generated during said shadow image mode with the patient being scanned by the X-ray source from only a single angular relationship relative to the patient, and (j) switch means connected with said computer means and with said video display means and operable in one switching condition to supply the respective sets of shadow image readings from the computer means to said video display means for display of the X-ray shadow image,--and operable in a second switching condition to supply the computed tomographic layer image from the computer means to said video display means for display thereby.

Claim 21

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including X-ray source means which produces a fan-shaped beam of X-ray energy having a lateral extent for penetrating a patient transverse layer at a transverse plane, and radiation measurement means receiving said fan-shaped beam and providing a set of a given number of respective individual measurements of radiation intensity of respective portions of the fan-shaped beam after transmission along respective laterally offset paths through the patient transverse layer, (c) angular scanning means coupled with the X-ray source means and operating in a tomographic angular scanning mode for producing rotational movement of said fan-shaped beam in said transverse plane through a wide range of angular relationships relative to the patient transverse layer so as to generate a sufficient number of sets of said individual measurements to define a tomographic layer image of the patient transverse layer, (d) computer means connected with said radiation measurement means and operating in said tomographic angular scanning mode for the computation of a transverse-layer image based on said sets of said individual measurements, (e) longitudinal scanning means operating in a shadow image generating mode for producing longitudinal movement of the patient support relative to the fan-shaped beam of X-ray energy in the longitudinal direction of the patient support and effecting the production of successive sets of said individual measurements from the radiation measurement means in successive relative longitudinal positions of the patient support while the measuring arrangement is locked in a single angular relationship, and supplying the successive sets of individual measurements to said computer means for the generation of an X-ray shadow image of the patient having a longitudinal extent corresponding to the extent of relative longitudinal movement of the patient support produced during said shadow image generating mode, and having a transverse extent corresponding to the lateral extent of said fan-shaped beam, (f) said longitudinal scanning means in said shadow image generating mode matching the rate of said relative longitudinal movement of said patient support and the frequency of the production of said successive sets of individual measurements from the radiation measurement means to obtain a predetermined resolution of said X-ray shadow image in the longitudinal direction generally corresponding with the image resolution which is given by said number of individual measurements produced by said radiation measurement means.

Claim 22

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including X-ray source means which produces a fan-shaped beam of X-ray energy having a lateral extent for penetrating a patient transverse layer at a transverse plane, and radiation measurement means receiving said fan-shaped beam and providing a set of a given number of respective individual measurements of radiation intensity of respective portions of the fan-shaped beam after transmission along respective laterally offset paths through the patient transverse layer, (c) angular scanning means coupled with the X-ray source means and operating in a tomographic angular scanning mode for producing rotational movement of said fan-shaped beam in said transverse plane through a wide range of angular relationships relative to the patient transverse layer so as to generate a sufficient number of sets of said individual measurements to define a tomographic layer image of the patient transverse layer, (d) computer means connected with said radiation measurement means and operating in said tomographic angular scanning mode for the computation of a transverse-layer image based on said sets of said individual measurements, (e) longitudinal scanning means operating in a shadow image generating mode for producing longitudinal movement of the patient support relative to the fan-shaped beam of X-ray energy in the longitudinal direction of the patient support and effecting the production of successive sets of said individual measurements from the radiation measurement means in successive relative longitudinal positions of the patient support while the measuring arrangement is locked in a single angular relationship, and supplying the successive sets of individual measurements to said computer means for the generation of an X-ray shadow image of the patient having a longitudinal extent corresponding to the extent of relative longitudinal movement of the patient support produced during said shadow image generating mode, and having a transverse extent corresponding to the lateral extent of said fan-shaped beam, (f) said longitudinal scanning means in said shadow image generating mode matching the rate of said relative longitudinal movement of said patient support and the frequency of the production of said successive sets of individual measurements from the radiation measurement means to obtain a predetermined resolution of said X-ray shadow image in the longitudinal direction generally corresponding with the image resolution which is given by said number of individual measurements produced by said radiation measurement means.

Claim 23

Tomographic apparatus according to claim 15, wherein the X-ray measuring arrangement is longitudinally and rotationally fixedly located during said shadow image generating mode, and the patient support is longitudinally driven by means of said longitudinal scanning means.

Claim 24

Tomographic apparatus according to claim 15, with an image display means for visually reproducing an X-ray shadow image of the patient based on the successive sets of individual measurements produced in said shadow image generating mode.

Claim 25

Tomographic apparatus according to claim 15, with said radiation measurement means producing said number of respective individual measurements in each of the successive relative longitudinal positions of the patient support during said shadow image generating mode, and said number of individual measurements being at least two hundred and forty-two.

Claim 26

Tomographic apparatus according to claim 15, with said patient support having location measurement means for identifying the longitudinal position of the patient support relative to said X-ray measurement arrangement, image display means coupled with said computer means for visually reproducing an X-ray shadow image of the patient based on the successive sets of individual measurements produced in said shadow image generating mode and for visually displaying, along with the X-ray shadow image, means for identifying the respective longitudinal positions of respective segments of the displayed X-ray shadow image in relation to said X-ray measurement arrangement.

Claim 27

Tomographic apparatus according to claim 15, wherein the radiation measurement means is comprised of a bank of respective detectors for receiving the respective portions of the fan-shaped beam, said longitudinal scanning means during said shadow image generating mode turning on the X-ray source means only when the measuring arrangement and the patient support are in successive relative longitudinal positions which are successively offset longitudinally by a longitudinal increment substantially corresponding to the image resolution given by the number of detectors of said bank.

Claim 28

Tomographic apparatus according to claim 20, with said bank of detectors comprising at least two hundred and forty-two detectors arranged for receiving respective portions of the fan-shaped beam.

Claim 29

Tomographic apparatus for the production of transverse-layer images of a patient comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including X-ray source means which produces a fan-shaped beam of X-ray energy having transverse extent for penetrating a patient transverse layer at a transverse plane, and radiation measurement means receiving said fan-shaped beam and providing a set of respective individual measurement readings representing radiation intensity of respective transversely offset portions of the fan-shaped beam after transmission along respective transversely offset paths through the patient transverse layer, (c) angular scanning means coupled with the X-ray source means and operating in a tomographic angular scanning mode for producing rotational movement of said fan-shaped beam in said transverse plane through a wide range of angular relationships relative to the patient transverse layer so as to generate a sufficient number of sets of said individual measurement readings to define a tomographic layer image of the patient transverse layer, (d) computer means connected with said radiation measurement means and operating in said tomographic angular scanning mode for the computation of a transverse-layer image based on said sets of said individual measurement readings, and (e) longitudinal scanning means operating in an automatic shadow image generating mode for producing longitudinal movement of the patient support relative to the fan-shaped beam of X-ray energy in the longitudinal direction of the patient support and automatically effecting the production of successive sets of said individual measurement readings from the radiation measurement means in successive relative longitudinal positions of the patient support while the measuring arrangement is locked in a single angular relationship, and supplying the successive sets of individual measurement readings to said computer means for the generation of an X-ray shadow image of the patient having a longitudinal extent corresponding to the extent of relative longitudinal movement of the patient support produced during said automatic shadow image generating mode, and having a transverse extent corresponding to the transverse extent of said fan-shaped beam.

Claim 30

Tomographic apparatus for the production of transverse-layer images of a patient comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including X-ray source means which produces a fan-shaped beam of X-ray energy having transverse extent for penetrating a patient transverse layer at a transverse plane, and radiation measurement means receiving said fan-shaped beam and providing a set of respective individual measurement readings representing radiation intensity of respective transversely offset portions of the fan-shaped beam after transmission along respective transversely offset paths through the patient transverse layer, (c) angular scanning means coupled with the X-ray source means and operating in a tomographic angular scanning mode for producing rotational movement of said fan-shaped beam in said transverse plane through a wide range of angular relationships relative to the patient transverse layer so as to generate a sufficient number of sets of said individual measurement readings to define a tomographic layer image of the patient transverse layer, (d) computer means connected with said radiation measurement means and operating in said tomographic angular scanning mode for the computation of a transverse-layer image based on said sets of said individual measurement readings, and (e) longitudinal scanning means operating in an automatic shadow image generating mode for producing longitudinal movement of the patient support relative to the fan-shaped beam of X-ray energy in the longitudinal direction of the patient support and automatically effecting the production of successive sets of said individual measurement readings from the radiation measurement means in successive relative longitudinal positions of the patient support while the measuring arrangement is locked in a single angular relationship, and supplying the successive sets of individual measurement readings to said computer means for the generation of an X-ray shadow image of the patient having a longitudinal extent corresponding to the extent of relative longitudinal movement of the patient support produced during said automatic shadow image generating mode, and having a transverse extent corresponding to the transverse extent of said fan-shaped beam.

Claim 31

Tomographic apparatus according to claim 22, wherein the X-ray measuring arrangement is longitudinally and rotationally fixedly located during said automatic shadow image generating mode, and the patient support is longitudinally driven by means of said longitudinal scanning means.

Claim 32

Tomographic apparatus according to claim 22, with an image display means connectable with said computer means for visually reproducing an X-ray shadow image of the patient based on the successive sets of individual measurement readings produced in said automatic shadow image generating mode.

Claim 33

Tomographic apparatus according to claim 22, with said radiation measurement means producing a given number of respective individual measurement readings in each of the successive relative longitudinal positions of the patient support during said automatic shadow image generating mode, and said number of individual measurement readings being at least two hundred and forty-two.

Claim 34

Tomographic apparatus according to claim 22, with said patient support having location measurement means for identifying the longitudinal position of the patient support relative to said X-ray measurement arrangement, image display means coupled with said computer means for visually reproducing an X-ray shadow image of the patient based on the successive sets of individual measurement readings produced in said automatic shadow image generating mode and for visually displaying, along with the X-ray shadow image, means for identifying the respective longitudinal positions of respective segments of the displayed X-ray shadow image in relation to said X-ray measurement arrangement.

Claim 35

Tomographic apparatus according to claim 22, wherein the radiation measurement means is comprised of a bank of respective detectors for receiving the respective transversely offset portions of the fan-shaped beam, said longitudinal scanning means during said automatic image generating mode turning on the X-ray source means only when the measuring arrangement and patient support are in successive relative longitudinal positions which are successively offset longitudinally by a longitudinal increment substantially corresponding to the image resolution given by the number of detectors of said bank.

Claim 36

Tomographic apparatus according to claim 27, with said bank of detectors comprising at least two hundred and forty-two detectors arranged for receiving respective transversely offset portions of the fan-shaped beam.

Claim 37

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including an X-ray source which produces a beam of X-ray energy for penetrating a patient transverse layer lying in a transverse plane, and radiation measurement means which provides a set of measurement readings which are measures of the radiation intensity of the transmitted beam over the transverse extent of the patient transverse layer, (c) angular scanning means coupled with the X-ray source for producing rotational movements of the beam of X-ray energy through a wide range of angular relationships to the patient transverse layer so as to generate a sufficient number of sets of measurement readings to define a tomographic layer image, (d) longitudinal scanning means producing longitudinal movement of the patient support relative to said beam of X-ray energy and producing measurement readings from the radiation measurement means in successive longitudinal positions of said patient support relative to said beam of X-ray energy in an automatic shadow image generating mode while the beam is in a single angular relationship with respect to the patient support, and (e) shadow image storage means operating during said automatic shadow image generating mode for the storage of a set of measurement readings from the radiation measurement means in each of the successive longitudinal positions of said patient support relative to said beam of X-ray energy for defining an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of longitudinal movement produced by said longitudinal scanning means during said automatic shadow image generating mode.

Claim 38

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including an X-ray source which produces a beam of X-ray energy for penetrating a patient transverse layer lying in a transverse plane, and radiation measurement means which provides a set of measurement readings which are measures of the radiation intensity of the transmitted beam over the transverse extent of the patient transverse layer, (c) angular scanning means coupled with the X-ray source for producing rotational movements of the beam of X-ray energy through a wide range of angular relationships to the patient transverse layer so as to generate a sufficient number of sets of measurement readings to define a tomographic layer image, (d) longitudinal scanning means producing longitudinal movement of the patient support relative to said beam of X-ray energy and producing measurement readings from the radiation measurement means in successive longitudinal positions of said patient support relative to said beam of X-ray energy in an automatic shadow image generating mode while the beam is in a single angular relationship with respect to the patient support, and (e) shadow image storage means operating during said automatic shadow image generating mode for the storage of a set of measurement readings from the radiation measurement means in each of the successive longitudinal positions of said patient support relative to said beam of X-ray energy for defining an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of longitudinal movement produced by said longitudinal scanning means during said automatic shadow image generating mode.

Claim 39

Tomographic apparatus according to claim 29, wherein the beam of X-ray energy is longitudinally and rotationally fixedly located during said automatic shadow image generating mode, and the patient support is longitudinally driven by means of said longitudinal scanning means.

Claim 40

Tomographic apparatus according to claim 29, with an image display means connectable with said shadow image storage means for visually reproducing an X-ray shadow image of the patient based on the successive sets of measurement readings produced in said automatic shadow image generating mode.

Claim 41

Tomographic apparatus according to claim 29, with said radiation measurement means producing a given number of respective individual measurement readings in each of the successive relative longitudinal positions of the patient support during said automatic shadow image generating mode, and said number of individual measurement readings being at least two hundred and forty-two.

Claim 42

Tomographic apparatus according to claim 29, with said patient support having location measurement means for identifying the longitudinal position of the patient support relative to said X-ray measurement arrangement, and image display means coupled with said shadow image storage means for visually reproducing an X-ray shadow image of the patient based on the successive sets of measurement readings produced in said automatic shadow image generating mode and visually displaying, along with the X-ray shadow image, means for identifying the respective longitudinal positions of respective segments of the displayed X-ray shadow image in relation to said X-ray measurement arrangement.

Claim 43

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including an X-ray source which produces a fan-shaped beam of X-ray energy for penetrating a patient transverse layer at a transverse plane, and radiation measurement means in said transverse plane which provides a set of measurement readings which are measures of the radiation intensity of the transmitted fan-shaped beam, (c) tomographic angular scanning means coupled with the X-ray source for producing rotational movements of said fan-shaped beam in said transverse plane through a wide range of angular relationships relative to the patient transverse layer so as to generate a sufficient number of sets of measurement readings to define a tomographic layer image of the patient transverse layer, (d) longitudinal scanning means operating in a shadow image generating mode for producing relative longitudinal movement between the measuring arrangement and the patient support in the longitudinal direction of the latter during storage of the measurement readings from the radiation measurement means, and including (e) control means operating in said shadow image generating mode for intermittently turning on said X-ray source such that the X-ray source is pulsed during the relative longitudinal movement of said patient support through successive relative longitudinal positions while the X-ray source is in a single angular relationship relative to said patient support, and (f) shadow image storage means operating in said shadow image generating mode for the storage of a set of measurement readings from the radiation measurement means in each of the successive relative longitudinal positions for defining an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of relative longitudinal movement produced by said longitudinal scanning means during operation of said control means in said shadow image generating mode, (g) said control means operating in said shadow image generating mode for correlating the frequency of the intermittent turning on of the X-ray source with the rate of operating of the longitudinal scanning means in producing said relative longitudinal movement such that said X-ray source is pulsed at said successive relative longitudinal positions which define said X-ray shadow image of the patient and such that said X-ray energy penetrates successive patient regions with the single angular relationship to said patient support at said successive relative longitudinal positions during the operation of said control means in said shadow image generating mode.

Claim 44

Tomographic apparatus for the production of transverse-layer images of a patient, comprising (a) a patient support having a longitudinal direction, (b) an X-ray measuring arrangement including an X-ray source which produces a fan-shaped beam of X-ray energy for penetrating a patient transverse layer at a transverse plane, and radiation measurement means in said transverse plane which provides a set of measurement readings which are measures of the radiation intensity of the transmitted fan-shaped beam, (c) tomographic angular scanning means coupled with the X-ray source for producing rotational movements of said fan-shaped beam in said transverse plane through a wide range of angular relationships relative to the patient transverse layer so as to generate a sufficient number of sets of measurement readings to define a tomographic layer image of the patient transverse layer, (d) longitudinal scanning means operating in a shadow image generating mode for producing relative longitudinal movement between the measuring arrangement and the patient support in the longitudinal direction of the latter during storage of the measurement readings from the radiation measurement means, and including (e) control means operating in said shadow image generating mode for intermittently turning on said X-ray source such that the X-ray source is pulsed during the relative longitudinal movement of said patient support through successive relative longitudinal positions while the X-ray source is in a single angular relationship relative to said patient support, and (f) shadow image storage means operating in said shadow image generating mode for the storage of a set of measurement readings from the radiation measurement means in each of the successive relative longitudinal positions for defining an X-ray shadow image of the patient having a substantial transverse extent and having a longitudinal extent corresponding to the range of relative longitudinal movement produced by said longitudinal scanning means during operation of said control means in said shadow image generating mode, (g) said control means operating in said shadow image generating mode for correlating the frequency of the intermittent turning on of the X-ray source with the rate of operating of the longitudinal scanning means in producing said relative longitudinal movement such that said X-ray source is pulsed at said successive relative longitudinal positions which define said X-ray shadow image of the patient and such that said X-ray energy penetrates successive patient regions with the single angular relationship to said patient support at said successive relative longitudinal positions during the operation of said control means in said shadow image generating mode.

Claim 45

Tomographic apparatus according to claim 34, with said control means automatically turning on said X-ray source during operation in said shadow image generating mode with a frequency so correlated with said rate of relative longitudinal movement of said patient support that the X-ray source is pulsed only at successive relative longitudinal positions which are separated by a distance substantially corresponding to the transverse image resolution given by said radiation measurement means.

Claim 46

Tomographic apparatus according to claim 34, with said radiation measurement means comprising a bank of detectors which are successively offset from each other in a transverse direction for receiving said fan-shaped beam of X-ray energy from said X-ray source, the number of successively offset detectors of said bank providing a transverse image resolution in the transverse direction, said control means automatically turning on said X-ray source during operation in said shadow image generating mode with a frequency so correlated with said rate of relative longitudinal movement of said patient support that the X-ray source is pulsed only at successive longitudinal positions which are separated by a longitudinal increment substantially corresponding to said transverse image resolution given by said number of successively offset detectors of said bank.

Claim 47

Tomographic apparatus according to claim 36, with said bank of detectors having at least two hundred and forty-two individual detectors.