Camera-based x-ray digital image detector
View Patent ↗A camera-based x-ray digital image detectors can contain an assembly of a scintillator screen, a wide-angle optical lens or fisheye lens, and a digital image sensor. Images formed by x-ray radiation on the scintillator screen can be projected onto a much smaller area image sensor through a fisheye or super-wide-angle optical lens, hence forming a highly distorted image thereon. Transparent lead-contained glasses or plastics can be utilized to shield image sensor from x-ray damage. Imaging distortion and light falloff caused by the lens optics can be corrected by software algorithms. Sub-millimeter resolution may be achieved with reduced design complexity and substantially lower manufacturing costs.
1. An x-ray digital image detector comprising:
a scintillator screen, for capturing an x-ray image;
a wide-angle fisheye lens for transferring the x-ray image from the scintillator screen to a digital image sensor; and
an x-ray shield positioned between the scintillator screen and the digital image sensor, for protecting the digital image sensor from damaging x-rays.
2. The x-ray digital image detector of claim 1 , wherein the digital image sensor is selected from the group consisting of a charge-coupled device (CCD) and a complimentary metal oxide semiconductor (CMOS)-based image sensor.
3. The x-ray digital image detector of claim 1 , further including a system for providing a software correction algorithm to rectify imaging distortion.
4. The x-ray digital image detector of claim 1 , further including a system for providing a light intensity correction algorithm to compensate for changes in the solid angles of the received light.
5. The x-ray digital image detector of claim 1 , wherein the fisheye lens has a focal length selected from the group of about 15 mm or less.
6. The x-ray digital image detector of claim 1 , further including a chamber for housing the image sensor, and wherein the chamber is filled with an inert gas.
7. The x-ray digital image detector of claim 1 , further including a Peltier cooling plate positioned adjacent to the digital image sensor for reducing thermal noise in the digital image sensor.
8. The x-ray digital image detector of claim 1 , wherein the scintillator screen is selected from the group consisting of a Gd2O2S:Tl scintillator screen and a needle CsI:TI scintillator screen.
9. The x-ray digital image detector of claim 1 , wherein the distance between the 10 scintillator screen and the digital image sensor is about 200 mm or less.
10. The x-ray digital image detector of claim 1 , wherein the detector is configured to have a resolution of about one millimeter.
11. The x-ray digital image detector of claim 1 , wherein the detector is configured to have a sub-millimeter resolution.
12. A method of producing a digital image from an x-ray image on a scintillator screen, the method comprising:
capturing an x-ray image on a scintillator screen;
transferring the x-ray image on the scintillator screen to a digital image sensor via a wide-angle fisheye lens; and
protecting the digital image sensor from damaging x-rays by positioning an x-ray shield between the scintillator screen and the digital image sensor.
13. The method of claim 12 , further including rectifying image distortion from the digital image sensor using software comprising a correction algorithm.
14. The method of claim 12 , further including compensating for changes in the solid angle of the received light.