Image capturing apparatus

Abstract

An image capturing apparatus illuminate and captures an image of an object using reflected light from the object. In the apparatus, a plurality of light-emitting devices are mounted in the periphery of an image sensor, and the light of the plurality of light-emitting devices is guided to an image capturing region by a light guide member for illumination. On the image capturing apparatus having the image capturing system disposed close to the illumination system, a hood is provided for optically intercepting the image capturing system from the illumination system, with a flange disposed thereon. The light reflected on the upper face of a filter can be intercepted from being incident on an image capturing system unit. Accordingly, output light not irradiating the object and causing an image capturing noise can be intercepted, which is effective for a clear photographed image.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a cross-sectional view of an image capturing apparatus according to one embodiment of the present invention.

FIG. 2 shows an exploded structural view of the image capturing apparatus shown in FIG. 1.

FIG. 3 shows a component layout diagram of the circuit board shown in FIG. 2.

FIG. 4 shows an explanation diagram of the relationship between a light-emitting device and a photodetector device shown in FIG. 2.

FIG. 5 shows an assembly diagram of the components shown in FIG. 2.

FIG. 6 shows a configuration diagram of the external finishing components shown in FIG. 1.

FIG. 7 shows a configuration diagram of the assembly of the assembled body shown in FIG. 2.

FIG. 8 shows an outer view of the image capturing apparatus shown in FIG. 1.

FIG. 9 shows an explanation diagram of the illumination system shown in FIG. 1.

FIG. 10 shows a configuration diagram of the light guide member and the light-emitting device shown in FIG. 9.

FIG. 11 shows a relation diagram of the emission intensity distribution of the light-emitting device, and the lower end portion of the light guide member shown in FIG. 10.

FIG. 12 shows a first operation explanation diagram of the light guide member shown in FIG. 10.

FIG. 13 shows a second operation explanation diagram of the light guide member shown in FIG. 10.

FIG. 14 shows a third operation explanation diagram of the light guide member shown in FIG. 10.

FIG. 15 shows a light intensity distribution diagram using the light guide member shown in FIG. 10.

FIG. 16 shows a perspective diagram of the hood shown in FIG. 1, viewed from an upper face side.

FIG. 17 shows a perspective diagram of the hood shown in FIG. 16, viewed from a lower face side.

FIG. 18 shows an operation diagram of the hood shown in FIGS. 16 and 17.

FIG. 19 shows a block diagram of a control circuit for the image capturing apparatus shown in FIG. 1.

FIG. 20 shows an image capturing process flowchart of the control circuit shown in FIG. 19.

FIG. 21 shows an explanation diagram of the distance measurement operation using the configuration shown in FIG. 19.

FIG. 22 shows an explanation diagram of the illumination configuration in the conventional image capturing apparatus.

FIG. 23 shows a configuration diagram of the conventional image capturing apparatus.

Claims

1. An image capturing apparatus for capturing an image of an object by illuminating the object and receiving reflected light from the object, comprising: an image sensor for receiving the reflected light;a plurality of light-emitting devices mounted in the peripheral positions of the image sensor;a light guide member for guiding light emitted from the plurality of light-emitting devices to an image capturing range, and illuminating the image capturing range;an optical unit accommodated inside the light guide member and for guiding the reflected light of the object in the illuminated image capturing range to the image sensor;an optical filter disposed on the object side of the optical unit and the light guide member; anda hood for optically intercepting the optical unit from the light guide member,wherein said hood further comprises a flange for intercepting the light reflected on the optical filter among the light output from the light guide member, from being incident to the optical unit.

2. The image capturing apparatus according to claim 1, wherein the plurality of light-emitting devices are mounted on a circuit board at predetermined intervals along a circle in the periphery of the image sensor, and wherein the light guide member comprises a ring-shaped configuration corresponding to the circle.

3. The image capturing apparatus according to claim 1, wherein the image sensor and the plurality of light-emitting devices are mounted on an identical circuit board.

4. The image capturing apparatus according to claim 1, wherein the hood comprises: a hood outside wall coupled with said flange and for optically intercepting the optical unit from the light guide member; anda hood bottom portion having an aperture for setting to the optical unit.

5. The image capturing apparatus according to claim 2, further comprising a diffusion plate for diffusing the light of the light-emitting devices, and disposed between the ring-shaped light guide member and the plurality of light-emitting devices.

6. The image capturing apparatus according to claim 3, further comprising a photo-detector device for monitoring the light of the light-emitting devices, and disposed between each plurality of light-emitting devices on the circuit board.

7. The image capturing apparatus according to claim 2, further comprising a distance-measuring light-emitting device mounted on the circuit board and for measuring a distance to the object.

8. The image capturing apparatus according to claim 1, wherein the plurality of light-emitting devices comprise light-emitting devices for emitting infrared light, and wherein the optical filter comprises an optical filter filtering visible light.

9. The image capturing apparatus according to claim 1, wherein the light guide member comprises: a lower end portion for introducing the light of the light-emitting devices;an upper end portion for outputting the light to the image capturing range; anda light guide portion for guiding the light of the light-emitting devices from the lower end portion to the upper end portion.

10. The image capturing apparatus according to claim 6, wherein the photo-detector device is disposed at a lower portion of the light guide member in such a position as to receive the light reflected at the lower portion of the light guide member among the light emitted from the light-emitting devices.

11. The image capturing apparatus according to claim 5, wherein the diffusion plate comprises a plurality of separate diffusion members, respectively corresponding to the plurality of light-emitting devices which are mounted on the circuit board at predetermined intervals along the circle in the periphery of the image sensor.

12. The image capturing apparatus according to claim 7, wherein the distance-measuring light-emitting device is mounted in such a position on the circuit board as to measure the distance to the object in the image capturing range using the image of the image sensor.

13. The image capturing apparatus according to claim 14, wherein the distance-measuring light-emitting device is mounted on the circuit board in an outer position of the light-emitting devices.

14. The image capturing apparatus according to claim 1, wherein the image sensor captures an image of a portion of a living body.