X-ray image intensifier system

Claim 2

An improved X-ray imaging system including: an X-ray generator having means for directing an X-ray beam through an externally located subject; an X-ray collimator device operatively disposed between the Xray generator and the subject and having adjustable means for regulating the cross-sectional size of the X-ray beam; an X-ray image intensifier tube including an input screen disposed to receive an X-ray image of the subject and having means for emitting a corresponding electron image, an output screen having means for converting an incident electron image into a corresponding visual image, and means for focussing an electron image emitted by the input screen onto the output screen; and wherein the improvement comprises means optically coupled to the output screen of the image intensifier tube for monitoring the size of the visual image.

Claim 3

An X-ray imaging system as set forth in claim 1 wherein the image size sensing means includes a plurality of light sensitive devices, each device being disposed in optical communication with a respective portion of the output screen.

Claim 4

An X-ray imaging system as set forth in claim 1 wherein the image size sensing means includes two concentric arrays of light sensitive devices defining an optimum image size therebetween.

Claim 5

An X-ray imaging system as set forth in claim 3 wherein the monitoring means includes a marginal area of the input screen electron-optically aligned with a marginal area of the output screen which, in turn, is disposed in optical communication with light sensitive devices in one of the concentric arrays.

Claim 6

An X-ray imaging system as set forth in claim 1 wherein the image size sensing means includes means for producing electrical signals indicative of the size of the visual image on the output screen.

Claim 7

An X-ray imaging system as set forth in claim 5 wherein the monitoring means includes control means electrically connected to the image size sensing means and coupled to the adjustable means of the collimator device for electrically evaluating the signals produced by the image size sensing means and operating the adjustable means of the collimator device accordingly.

Claim 8

An improved X-ray imaging system including: an X-ray generator having means for directing an X-ray beam through an externally located subject; an X-ray collimator device operatively disposed between the X-ray generator and the subject and having adjustable means for regulating the cross-sectional size of the X-ray beam: an X-ray image intensifier tube including an input screen disposed to receive an X-ray image of the subject and having means for emitting a corresponding electron image, an output screen having means for converting an incident electron image into a corresponding visual image, and means for focussing an electron image emitted by the input screen onto the output screen; wherein the improvement comprises image size sensing means optically coupled to the output screen for producing electrical signals indicative of the size of a visual image on the output screen; and control means electrically connected to the image sensing means and coupled to the adjustable means of the collimator device for evaLuating electrical signals received from the image size sensing means and in accordance therewith operating the adjustable means of the collimator device.

Claim 9

An improved X-ray imaging system including: an X-ray generator having means for directing an X-ray beam through an externally located subject; an X-ray collimator device operatively disposed between the X-ray generator and the subject and having adjustable means for regulating the cross-sectional size of the X-ray beam: an X-ray image intensifier tube including an input screen disposed to receive an X-ray image of the subject and having means for emitting a corresponding electron image, an output screen having means for converting an incident electron image into a corresponding visual image, and means for focussing an electron image emitted by the input screen onto the output screen; wherein the improvement comprises image size sensing means optically coupled to the output screen for producing electrical signals indicative of the size of a visual image on the output screen; and control means electrically connected to the image sensing means and coupled to the adjustable means of the collimator device for evaLuating electrical signals received from the image size sensing means and in accordance therewith operating the adjustable means of the collimator device.

Claim 10

An X-ray imaging system as set forth in claim 7 wherein the image size sensing means includes a plurality of light responsive devices, each being disposed in optical communication with a respective portion of the output screen and having means for an electrical signal in response to light received therefrom.

Claim 11

An X-ray imaging system as set forth in claim 8 wherein the image size sensing means also includes an optical fiber harness comprising a plurality of fiber optic bundles, each terminating at one end of the harness in a common facing on which an optical image of the output screen is projected and terminating at their respective other ends adjacent on operatively disposed, light responsive devices.

Claim 12

An X-ray imaging system as set forth in claim 9 wherein the ends of the fiber optic bundles in the common facing are disposed in inner and outer concentric arrays, the fiber optic bundles having ends in the inner array terminate at their other ends in a common facing operatively coupled to a first light responsive device and the fiber optic bundles having ends disposed in the outer array terminate at their other ends in a common facing operatively coupled to a second light responsive device.

Claim 13

An X-ray imaging system as set forth in claim 10 wherein the fiber optic bundles in the outer array are disposed in optical communication with respective marginal areas of the output screen and the fiber optic bundles in the inner array are disposed in the inner array are disposed in optical communication with respective portions of a central area of the output screen.

Claim 14

An X-ray imaging system as set forth in claim 11 wherein said marginal areas of the output screen are electron-optically aligned with respective marginal areas of the input screen.

Claim 15

An X-ray imaging system as set forth in claim 10 wherein the control means includes first circuit means electrically connected to the first light responsive device and interruptingly coupled to the adjustable means of the collimator device for operating the adjustable means in response to a predetermined minimal signal from the first light responsive device.

Claim 16

An X-ray imaging system as set forth in claim 11 wherein the control means also includes second circuit means electrically connected to the second light responsive device and interruptingly coupled to the adjustable means of the collimator device for operating the adjustable means in response to a signal from the second light responsive device.