Photoelectric conversion device, radiation detection apparatus, image processing system and driving method thereof

• US 20050061955A1
• Filed: 11/15/2004
• Published: 03/24/2005
• Est. Priority Date: 07/28/2000
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Endo, Tadao
• Granted Patent: US 7,098,461 B2
• Time in Patent Office: Days
• US Class Current: 250/214.R
• CPC Class Codes: G01T 1/2928 using solid state detectors
• CPC Class Codes: H04N 25/63 applied to dark current
• CPC Class Codes: H04N 5/32 Transforming X-rays cameras or camera modules for generating image signals from X-rays H04N23/30; circuitry of SSIS for transforming X-rays into image signals H04N25/30

Abstract

In a photoelectric conversion device, in order to suppress alteration of its properties during a long time use, lower the decrease of the S/N ratio due to a dark current output, and shorten image-pickup cycles, MIS type photoelectric conversion elements using an amorphous semiconductor material are connected with an electric power source for applying bias for photoelectric conversion, an electric power for resetting an accumulated electric charge, and a setting point for applying zero bias at the time of non-operation of the element through a switch. Emitted x-rays from an x-ray source, which is a first light source, come into collision against phosphor after being transmitted through an object body to be inspected and then are absorbed in the phosphor to be converted into visible light rays. The visible light rays from the phosphor are radiated to the photoelectric conversion elements. Prior to reading out of the x-ray image, an LED light source is lighted. Switches are used for turning on the x-ray source and the LED light source. In this embodiment, there is a reading-out period and a non-reading-out period; the x-ray source is turned on during the reading-out period, and the LED light source is turned on during the non-reading-out period.

Claims

1-19. -19. (Cancelled)

20. A radiation detection apparatus comprising:

a plurality of photoelectric conversion elements,

a light source for radiating a light ray, its wavelength including a wavelength region of light absorption of the photoelectric conversion elements,

an outer casing that houses the photoelectric conversion elements and the light source.

21. The radiation detection apparatus according to claim 20, further comprising a light guide plate.

22. The radiation detection apparatus according to claim 21, wherein the light source provided in the outer casing is arranges on the side face of the light guide plate.

23. The radiation detection apparatus according to claim 20, wherein the photoelectric conversion elements are arranged on an insulating substrate, and the insulating substrate is also used as a light guide plate.

24. The radiation detection apparatus according to claim 20, wherein the light source is arranged on the outside of a region where the photoelectric conversion elements are formed.

25. The radiation detection apparatus according to claim 20, wherein the photoelectric conversion device further comprises a wavelength converter for converting radiation radiated from the radiation source to light, and the light source is arranged on the outside of a region where the wavelength converter is formed.

26. The radiation detection apparatus according to claim 20, the photoelectric converting elements including a first electrode layer and a second electrode layer, an insulating layer formed between the first and second electrode layers for inhibiting a first type of carriers from passing through the layer, a semiconductor layer, and an injection blocking layer for inhibiting said first type of carriers from being injected into the semiconductor layer, and the light source emits light having a wavelength for generating carriers which absorb light in the semiconductor layer and remain in an interface with the insulating layer.

27. An image data processing system, comprising:

the radiation detection apparatus according to claim 20, a radiation source; and

control means for independently controlling the radiation source, the light source and the photoelectric conversion device.