Image capturing apparatus having distance measurement function

Abstract

An image capturing apparatus illuminates an object and captures an image of the object using the reflected light from the object. The image capturing apparatus includes an image sensor for capturing an image of the object by receiving reflected light, distance-measuring light-emitting devices for irradiating the object with spot light, and a control circuit for driving the distance-measuring light-emitting devices, detecting the spot light positions of the distance-measuring light-emitting devices from an image captured by the image sensor, and obtaining the distance to the object. The image sensor provided for capturing an image of the object can be used as a photodetector device for distance measurement. With this, it becomes unnecessary to separately provide a photodetector device for distance measurement, which enables miniaturization of the image capturing apparatus, as well as cost reduction.

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

FIG. 17 shows an imaging process flowchart of the control circuit shown in FIG. 16.

FIG. 18 shows an explanation diagram of distance measurement operation using the configuration shown in FIG. 16.

FIG. 19 shows an explanation diagram of the conventional palm image capturing apparatus.

FIG. 20 shows a principle explanation diagram of the conventional palm image capturing apparatus.

FIG. 21 shows an explanation diagram of the conventional palm authentication technique.

FIG. 22 shows another explanation diagram of the conventional palm authentication technique.

FIG. 23 shows an explanation diagram of an illumination configuration in the conventional image capturing apparatus.

FIG. 24 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 capturing the image by receiving the reflected light;distance-measuring light-emitting device for irradiating the object with spot light; anda control circuit for driving the distance-measuring light-emitting device, detecting the spot light position of the distance-measuring light-emitting device from the image captured by the image sensor, and obtaining a distance to the object from the detected position.

2. The image capturing apparatus according to claim 1, wherein the distance-measuring light-emitting device is disposed to the image sensor in the positions of irradiating within an image capturing range of the image sensor with the spot light.

3. The image capturing apparatus according to claim 1, wherein the distance-measuring light-emitting device is constituted of at least three distance-measuring light-emitting devices disposed in different positions centered at the image sensor.

4. The image capturing apparatus according to claim 3, wherein the at least three distance-measuring light-emitting devices are disposed in opposite positions centered at the image sensor.

5. The image capturing apparatus according to claim 4, wherein the control circuit detects the spot light positions of each distance-measuring light-emitting device from the image captured by the image sensor, and obtains the inclination of the object from the detected positions.

6. The image capturing apparatus according to claim 1, wherein the distance-measuring light-emitting device is mounted on a circuit board having the image sensor mounted thereon.

7. The image capturing apparatus according to claim 1, further comprising an illumination mechanism for illuminating the object at the time of image capturing and disposed in the periphery of the image sensor, wherein the distance-measuring light-emitting device is disposed on the outer sides of the illumination mechanism.

8. The image capturing apparatus according to claim 7, wherein the illumination mechanism comprises: a plurality of light-emitting devices mounted in the peripheral positions of the image sensor; anda ring-shaped light guide member for guiding the light of the plurality of light-emitting devices to an image capturing range and illuminating the image capturing range,and wherein further comprises an optical unit accommodated inside the ring of the ring-shaped light guide member and for guiding reflected light of the object in the illuminated image capturing range to the image sensor.

9. The image capturing apparatus according to claim 8, further comprising a circuit board mounted the image sensor, the distance-measuring light-emitting device and the plurality of light-emitting devices.

10. The image capturing apparatus according to claim 9, wherein the plurality of light-emitting devices are mounted on the circuit board at predetermined intervals along a circle in the periphery of the image sensor, and wherein the light guide member has a ring-shaped structure corresponding to the circle.

11. The image capturing apparatus according to claim 8, 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.

12. The image capturing apparatus according to claim 8, wherein the plurality of light-emitting devices are configured of light-emitting devices for emitting infrared rays, and wherein at least on the incident plane of the optical unit, an optical filter for filtering the visible light is disposed.

13. The image capturing apparatus according to claim 8, wherein the light guide member comprises: a lower end portion for guiding the light of the light-emitting devices;an upper end portion for outputting the light in 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.

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