Imaging device and imaging method

• US 10,877,288 B2
• Filed: 08/09/2017
• Issued: 12/29/2020
• Est. Priority Date: 08/18/2016
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Mitani, Hitoshi, Wakazono, Masafumi
• Primary Examiner(s): Ye, Lin
• Assistant Examiner(s): Yoder, III, Chriss S
• Application Number:
  US16/302,385
• Publication Number:
  US 20190310487A1
• Time in Patent Office: 1,238 Days
• CPC Class Codes: G01J 4/04 Polarimeters using electric detection means G01J4/02 takes precedence
• CPC Class Codes: G02B 27/281 used for attenuating light intensity, e.g. comprising rotatable polarising elements
• CPC Class Codes: G02B 27/286 for controlling or changing the state of polarisation, e.g. transforming one polarisation state into another G02B5/3083 takes precedence; light guide coupling means utilising polarising elements G02B6/34
• CPC Class Codes: G02B 5/3016 involving passive liquid crystal elements optical properties of liquid crystals G02F1/0063; polarising elements associated with active liquid crystal devices G02F1/133528
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/743 Bracketing, i.e. taking a series of images with varying exposure conditions
• CPC Class Codes: H04N 5/2621 Cameras specially adapted for the electronic generation of special effects during image pickup, e.g. digital cameras, camcorders, video cameras having integrated special effects capability

Abstract

There is provided an imaging device including: an imaging section configured to set pixels as polarization pixels having any of polarization directions, the pixels generating pixel signals on the basis of incident light; a polarization direction rotating section provided on an incidence plane side of the imaging section, and configured to rotate a polarization direction of the incident light; and a control section configured to control the imaging section and the polarization direction rotating section to generate a polarized image or a non-polarized image having higher resolution than resolution of the polarized image.

Claims

1. An imaging device comprising:

an imager including a plurality of pixels arranged in an array, respective ones of the plurality of pixels including a photosensitive element and a polarization filter having a predetermined polarization angle with respect to a plane of the array, the imager configured to generate an image signal from the plurality of pixels;

a polarizing element provided on an incidence plane side of the imager; and

control circuitry configured to change a polarization direction of incident light by causing the polarizing element to rotate with respect to the imager, wherein

the control circuitry is configured to switch between a polarized image having a first resolution and a non-polarized image having a second resolution higher than the first resolution, and

the control circuitry is configured to generate the non-polarized image by rotating the polarization direction of the incident light n (where n represents a natural number) times as large as 180 degrees during an exposure period of the imager.

2. The imaging device according to claim 1, wherein

the control circuitry is configured to generate the non-polarized image by using images obtained by performing imaging at rotational positions in the polarization direction.

3. The imaging device according to claim 2, wherein

the control circuitry is configured to perform imaging at a position at which a polarization direction of the polarizing element is equal to a polarization direction of a respective one of the plurality of pixels.

4. The imaging device according to claim 2, further comprising:

image signal processing circuitry configured to combine images for each of the plurality of pixels to generate the non-polarized image, the images being obtained by the imager performing imaging two or more times.

5. The imaging device according to claim 4, wherein

in a case where rotation of the polarization direction of the polarizing element is stopped, and the imaging section performs imaging, the image signal processing circuitry:

sets a first signal generated by a first pixel of the plurality of pixels having a first polarization direction that is vertical or parallel to an optical axis of the polarizing element as indicating a first polarization component of the incident light having a polarization direction that agrees with the first polarization direction, and

sets a second signal generated by a second pixel of the plurality of pixels having a second polarization direction that is not vertical or parallel to the optical axis of the polarizing element as indicating a second polarization component of the incident light rotated by the polarizing element in accordance with an angular difference between the optical axis of the polarizing element and the second polarization direction.

6. The imaging device according to claim 1, wherein

in a case where the non-polarized image is generated, the control is configured to stop a light emitting section from emitting illumination light.

7. The imaging device according to claim 1, wherein

the control circuitry is configured to generate the polarized image in an imaging operation that uses a light emitting section.

8. The imaging device according to claim 1, wherein

the polarizing element includes a half-wave plate, and a rotation driving section that rotates the half-wave plate by using an optical axial direction of the incident light as a rotation axis.

9. The imaging device according to claim 1, wherein

the polarizing element includes a liquid crystal element with a rotating polarization direction.

10. The imaging device according to claim 1, wherein

the polarizing element is attachable and detachable.

11. The imaging device according to claim 10, wherein

in a case where the polarizing element is detached, and in a case where the polarizing element stops rotation of the polarization direction, the control circuitry generates the polarized image.

12. The imaging device according to claim 1, wherein

respective polarization directions of the corresponding ones of the plurality of pixels have an equal angular interval.

13. The imaging device according to claim 1, further comprising:

a color filter including a plurality of color component units, respective ones of the plurality of color component units corresponding to one of a plurality of colors,

wherein the plurality of color component units are arranged in a predetermined color pattern.

14. A vehicle comprising the imaging device according to claim 1.

15. An imaging method comprising:

controlling, by control circuitry, an imager and a polarizing element positioned on an incidence plane side of the imager, the imager including a plurality pixels arranged in an array, respective ones of the plurality of pixels including a photosensitive element and a polarization filter having a predetermined polarization angle with respect to a plane of the array, the imager configured to generate an image signal from the plurality of pixels;

switching the control circuitry between a polarized image having a first resolution and a non-polarized image having a second resolution higher than the first resolution; and

generating, by the control circuitry, the non-polarized image by rotating the polarization direction of the incident light n (where n represents a natural number) times as large as 180 degrees during an exposure period of the imager.

16. A computing device, comprising:

a processor;

a memory; and

an imaging device, the imaging device including;

an imager including a plurality of pixels arranged in an array, respective ones of the plurality of pixels including a photosensitive element and a polarization filter having a predetermined polarization angle with respect to a plane of the array, the imager configured to generate an image signal from the plurality of pixels;

a polarizing element provided on an incidence plane side of the imager; and

control circuitry configured to change a polarization direction of incident light by causing the polarizing element to rotate with respect to the imager, wherein

the control circuitry is configured to switch between a polarized image having a first resolution and a non-polarized image having a second resolution higher than the first resolution, and

the control circuitry is configured to generate the non-polarized image by rotating the polarization direction of the incident light n (where n represents a natural number) times as large as 180 degrees during an exposure period of the imager.

17. A vehicle comprising the computing device according to claim 16.