Method and apparatus for variable depth laminagraphy

Claim 1

A method of preparing records for display of variable depth laminagraphy which comprises: disposing a subject to be radiographed on a support member between a source of penetrating radiation and a radiation sensitive recording medium in the field of radiation from said source, moving said source of penetrating radiation through successive positions disposed in a predetermined linear path relative to said subject while rotating said source so that said field of radiation is rotated about an axis adjacent said recording medium, maintaining said recording medium in that part of the field of radiation which penetrates said subject in the area of interest to record an image of said subject in a plurality of exposures as said source moves through a plurality of positions in the predetermined path, exposing the subject and the recording medium to radiation at plural arbitrary points of differing angulation about said axis along said path, changing the recording medium after each exposure to produce a set of radiographic records, and recording the relative angulation for the point of exposure on each radiographic record.

Claim 2

A method of preparing records for display of variable depth laminagraphy which comprises: disposing a subject to be radiographed on a support member between a source of penetrating radiation and a radiation sensitive recording medium in the field of radiation from said source, moving said source of penetrating radiation through successive positions disposed in a predetermined linear path relative to said subject while rotating said source so that said field of radiation is rotated about an axis adjacent said recording medium, maintaining said recording medium in that part of the field of radiation which penetrates said subject in the area of interest to record an image of said subject in a plurality of exposures as said source moves through a plurality of positions in the predetermined path, exposing the subject and the recording medium to radiation at plural arbitrary points of differing angulation about said axis along said path, changing the recording medium after each exposure to produce a set of radiographic records, and recording the relative angulation for the point of exposure on each radiographic record.

Claim 8

The method of producing a radiographic view of a selected lamina in a subject comprising the steps of: disposing a subject to be radiographed on a support member between a radiation source and a recording medium in the field of radiation from said source, moving the source in a straight line path relative to the subject while rotating said source so that said field of radiation is rotated about an axis adjacent said recording medium, maintaining said recording medium in that part of the field of radiation which penetrates said subject in the area of interest, exposing the subject to radiation from the source at plural successive arbitrary positions in the path of movement to expose said medium to radiation penetrating said subject at successively different arbitrary angles about said axis and thereby making a radiographic record thereof, changing the recording medium after each exposure and producing a set of at least four radiographic records each taken at a different angulation of exposure, recording information with respect to each radiographic record identifying the value of the arbitrary angulation of exposure thereof, superimposing the radiographic records so that the images of the subject can be viewed and superimposed, positioning each of the radiographic records in an initial position so that the images of a selected point in said subject are in registry whereby a clear image is produced of the lamina in which said selected point resides, and linearly shifting all the radiographic records simultaneously from the initial position to produce a clear image of another lamina, each radiographic record being shifted relative to any other record in accordance with the difference in angulation of exposure, such shifting being along a line and through a distance proportional to that which it would be shifted by: (1) cutting each radiographic record into a parallelogram having a parallelogram angle corresponding to the angulation of the exposure, (2) superimposing the set of parallelogram-shaped radiographic records on each other and allowing each of them to move only along the line of source movement relative thereto during exposure of the radiographic records, and (3) causing the set of parallelogram-shaped radiographic records to move along said last-mentioned line by perpendicular movement in unison of a pair of pins engaging opposite edges of the set of parallelogram-shaped radiographic records on a line parallel to said last-mentioned line.

Claim 9

The method of producing a radiographic view of a selected lamina in a subject comprising the steps of: disposing a subject to be radiographed on a support member between a radiation source and a recording medium in the field of radiation from said source, moving the source in a straight line path relative to the subject while rotating said source so that said field of radiation is rotated about an axis adjacent said recording medium, maintaining said recording medium in that part of the field of radiation which penetrates said subject in the area of interest, exposing the subject to radiation from the source at plural successive arbitrary positions in the path of movement to expose said medium to radiation penetrating said subject at successively different arbitrary angles about said axis and thereby making a radiographic record thereof, changing the recording medium after each exposure and producing a set of at least four radiographic records each taken at a different angulation of exposure, recording information with respect to each radiographic record identifying the value of the arbitrary angulation of exposure thereof, superimposing the radiographic records so that the images of the subject can be viewed and superimposed, positioning each of the radiographic records in an initial position so that the images of a selected point in said subject are in registry whereby a clear image is produced of the lamina in which said selected point resides, and linearly shifting all the radiographic records simultaneously from the initial position to produce a clear image of another lamina, each radiographic record being shifted relative to any other record in accordance with the difference in angulation of exposure, such shifting being along a line and through a distance proportional to that which it would be shifted by: (1) cutting each radiographic record into a parallelogram having a parallelogram angle corresponding to the angulation of the exposure, (2) superimposing the set of parallelogram-shaped radiographic records on each other and allowing each of them to move only along the line of source movement relative thereto during exposure of the radiographic records, and (3) causing the set of parallelogram-shaped radiographic records to move along said last-mentioned line by perpendicular movement in unison of a pair of pins engaging opposite edges of the set of parallelogram-shaped radiographic records on a line parallel to said last-mentioned line.

Claim 10

The method of producing a radiographic view of a selected lamina in a subject comprising the steps of: disposing a subject to be radiographed on a support member between a radiation source and a recording medium in the field of radiation fRom said source, disposing two radiation opaque markers in the vicinity of the subject at different distances from the recording medium, moving the source in a straight line path relative to the support member while rotating said source so that said field of radiation is rotated about an axis adjacent said recording medium, maintaining said recording medium in that part of the field of radiation which penetrates said subject in the area of interest, exposing the subject to radiation from the source at plural successive arbitrary positions in the path of movement to expose said medium to radiation penetrating said subject and said markers at successively different arbitrary angles about said axis and thereby making a radiographic record thereof, changing the recording medium after each exposure to produce a set of radiographic records each taken at a different angle relative to said subject, superimposing the radiographic records so that the images of the subject can be viewed and superimposed, positioning the radiographic records so that the images of a selected point in said subject are in registry whereby a clear image is produced of the lamina in which said point resides, and linearly shifting the radiographic records from one relative position to another along a line parallel to the relative movement between the source and the support member, and displacement of any other radiographic record having a ratio equal to the ratio of distances along said line between the images of the markers on the one radiographic record and the images of the markers on the other radiographic record whereby a clear image is produced of successive laminae of said subject.

Claim 11

The method of producing a radiographic view of a selected lamina in a subject comprising the steps of: disposing a subject to be radiographed on a support member between a radiation source and a recording medium in the field of radiation fRom said source, disposing two radiation opaque markers in the vicinity of the subject at different distances from the recording medium, moving the source in a straight line path relative to the support member while rotating said source so that said field of radiation is rotated about an axis adjacent said recording medium, maintaining said recording medium in that part of the field of radiation which penetrates said subject in the area of interest, exposing the subject to radiation from the source at plural successive arbitrary positions in the path of movement to expose said medium to radiation penetrating said subject and said markers at successively different arbitrary angles about said axis and thereby making a radiographic record thereof, changing the recording medium after each exposure to produce a set of radiographic records each taken at a different angle relative to said subject, superimposing the radiographic records so that the images of the subject can be viewed and superimposed, positioning the radiographic records so that the images of a selected point in said subject are in registry whereby a clear image is produced of the lamina in which said point resides, and linearly shifting the radiographic records from one relative position to another along a line parallel to the relative movement between the source and the support member, and displacement of any other radiographic record having a ratio equal to the ratio of distances along said line between the images of the markers on the one radiographic record and the images of the markers on the other radiographic record whereby a clear image is produced of successive laminae of said subject.