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

• US 6,965,111 B2
• Filed: 07/25/2001
• Issued: 11/15/2005
• Est. Priority Date: 07/28/2000
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Endo, Tadao
• Primary Examiner(s): GAGLIARDI, ALBERT J
• Application Number:
  US09/911,616
• Publication Number:
  US 20020024016A1
• Time in Patent Office: 1,574 Days
• Field of Search: 250/370.11, 250/370.08, 250/370.09, 250/484.4, 250/208.1
• US Class Current: 250/370.11
• 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. An image data processing system, comprising:

a photoelectric conversion device comprising a substrate provided with a plurality of photoelectric conversion elements and a light source for radiating light rays having no image data to a plurality of the photoelectric conversion elements;

a radiation source;

control means for independently controlling the radiation source, the light source, and the photoelectric conversion device, wherein the control means drives the radiation source during an image-pickup period and drives the light source during a non-image-pickup period; and

a light guide plate, wherein the light source is arranged on a side face of the light guide plate.

2. The image data processing system according to claim 1, wherein the radiation source is an X-ray source.

3. The image data processing system according to claim 1, wherein the light source is an LED, an EL, a cathode ray tube, or a semiconductor laser.

4. The image data processing system according to claim 1, further comprising an outer casing that houses the photoelectric conversion elements and the light source.

5. The image data processing system according to claim 1, wherein the light source is arranged on a side face of the light guide plate and on an outside of a region where the photoelectric conversion elements are formed.

6. The image data processing system according to claim 1, wherein the photoelectric conversion device further comprises a wavelength converter for converting radiation radiated from the radiation source to light, and

wherein the light source is arranged on a side face of the light guide plate and on an outside of a region where the photoelectric conversion elements are formed.

7. The image data processing system according to claim 1, the light source producing wavelengths including a wavelength region of light absorption of the photoelectric conversion elements.

8. The image data processing system according to claim 1, the photoelectric conversion 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 carrier from passing through the insulating layer, a semiconductor layer, and an injection blocking layer for inhibiting said first type of carrier from being injected into the semiconductor layer, and

wherein 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.

9. A radiation detection apparatus comprising:

a plurality of photoelectric conversion elements;

a light source for radiating a light ray, whose wavelength includes a wavelength region of light absorption of the photoelectric conversion elements; and

a light guide plate, wherein the light source is arranged on a side face of the light guide plate.

10. The radiation detection apparatus according to claim 9, wherein the photoelectric conversion elements are arranged on an insulating substrate, wherein the insulating substrate is also used as the light guide plate.

11. The radiation detection apparatus according to claim 9, wherein the light source is arranged on a side face of the light guide plate and on an outside of a region where the photoelectric conversion elements are formed.

12. The radiation detection apparatus according to claim 9, further comprising:

a radiation source; and

a wavelength converter for converting radiation radiated from the radiation source to light,

wherein the light source is arranged on a side face of the light guide plate and on an outside of a region where the photoelectric conversion elements are formed.

13. The radiation detection apparatus according to claim 9, wherein the light source is an LED, an EL, a cathode ray tube, or a semiconductor laser.

14. The radiation detection apparatus according to claim 9, further comprising an outer casing that houses the photoelectric conversion elements and the light source.

15. The radiation detection apparatus according to claim 9, wherein the light source produces wavelengths including a wavelength region of light absorption of the photoelectric conversion elements.

16. The radiation detection apparatus according to claim 9, wherein the photoelectric conversion elements include 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 carrier from passing through the insulating layer, a semiconductor layer, and an injection blocking layer for inhibiting said first type of carrier from being injected in to the semiconductor layer, and

wherein 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.