Imaging apparatus capable of generating an image using moire without a lens

Patent metadata

Field	Value
Publication number	US-10423002-B2
Application number	US-201515580039-A
Country	US
Kind code	B2
Filing date	Jun 17, 2015
Priority date	Jun 17, 2015
Publication date	Sep 24, 2019
Grant date	Sep 24, 2019

Abstract

The cost and power consumption of an imaging apparatus are reduced by facilitating detection of an incident angle of a light beam transmitted through a grating substrate. An image sensor converts an optical image captured by pixels arranged on an imaging surface and outputs the converted image signal. A modulator is configured to modulate intensity of light; and an image processing circuit performs image processing of the output image signal. The modulator has a grating substrate, a grating pattern formed on a back surface side of the grating substrate arranged in proximity to the light receiving surface of the image sensor; and a grating pattern formed on a front surface facing the back surface. Each of the grating patterns is constituted of concentric circles. The modulator performs intensity modulation on the light transmitted through the grating pattern and outputs the modulated light to the image sensor.

First claim

The invention claimed is:

1. An imaging apparatus comprising:
an image sensor configured to convert an optical image captured by a plurality of pixels arranged in an array on an imaging surface into an image signal and output the image signal;
a modulator provided on a light receiving surface of the image sensor and configured to modulate intensity of light; and
image processing circuitry configured to perform image processing of the image signal output from the image sensor,
wherein the modulator includes:
a transparent material;
a first grating pattern formed on a first surface of the transparent material arranged in proximity to the light receiving surface of the image sensor; and
a second grating pattern formed on a second surface facing the first surface,
each of the pattern and the second grating pattern is constituted of concentric circles,
the modulator performs intensity modulation on light transmitted through the second grating pattern by the pattern and outputs the modulated light to the image sensor, and
a pitch of the concentric circles in each of the pattern and the second grating pattern becomes finer in inverse proportion relative to a reference coordinate serving as a center of the concentric circles.

2. The imaging apparatus according to claim 1 ,
wherein the image processing circuitry calculates a frequency spectrum by performing a two-dimensional Fourier transform on the image signal output from the image sensor.

3. The imaging apparatus according to claim 1 ,
wherein the reference coordinate of the pattern and the reference coordinate of the second grating pattern are different in position.

4. The imaging apparatus according to claim 3 ,
wherein the reference coordinate of the pattern and the reference coordinate of the second grating pattern are shifted from each other in a short side direction of an image output from the image processing circuitry.

5. The imaging apparatus according to claim 1 ,
wherein the second grating pattern is formed of a cylindrical lens.

6. An imaging apparatus comprising:
an image sensor configured to convert an optical image captured by a plurality of pixels arranged in an array on an imaging surface into an image signal and output the image signal;
a modulator provided on a light receiving surface of the image sensor and configured to modulate intensity of light; and
image processing circuitry configured to perform image processing of the image signal output from the image sensor,
wherein the modulator includes:
a transparent material; and
a grating pattern formed on a second surface facing a first surface of the transparent material arranged in proximity to the light receiving surface of the image sensor,
the grating pattern is constituted of a concentric circles,
the image processing circuitry generates a moire fringe image obtained by adding moire to the image signal output from the image sensor, and
a pitch of the concentric circles in the grating pattern becomes finer in inverse proportion relative to a reference coordinate serving as a center of the concentric circles.

7. The imaging apparatus according to claim 6 ,
wherein the image processing circuitry calculates a frequency spectrum by performing two-dimensional Fourier transform on the generated moire fringe image.

8. The imaging apparatus according to claim 6 ,
wherein the grating pattern is formed of a cylindrical lens.

9. An imaging apparatus comprising:
an image sensor configured to convert an optical image captured by a plurality of pixels arranged in an array on an imaging surface into an image signal and output the image signal;
a modulator configured to modulate intensity of light; and
image processing circuitry configured to perform image processing of the image signal output from the image sensor,
wherein the modulator includes a display that is transparent and displays a first concentric pattern,
the image sensor captures the optical image transmitted through the display displaying the first concentric pattern,
the image processing circuitry processes a moire fringe image generated by the first concentric pattern displayed on the display and a second concentric pattern different from the first concentric pattern to generate an image,
the display displays the first concentric pattern under control of the image processing circuitry, and
a pitch of the first concentric pattern becomes finer in inverse proportion relative to a reference coordinate serving as a center of the first concentric pattern.

10. The imaging apparatus according to claim 9 ,
wherein the reference coordinate of the first concentric pattern displayed by the display and a reference coordinate serving as a center of the second concentric pattern are different in position.

11. The imaging apparatus according to claim 9 , further comprising:
an input interface configured to input information to designate a focus position of a subject,
wherein the image processing circuitry changes a shape of the first concentric pattern displayed by the display based on focus position information designated by the input interface.

12. The imaging apparatus according to claim 8 ,
wherein the image processing circuitry calculates a frequency spectrum by performing a two-dimensional Fourier transform on the image signal output from the image sensor.

13. The imaging apparatus according to claim 6 , further comprising:
an input interface configured to input information to designate a focus position of a subject,
wherein the image processing circuitry changes a shape of the concentric circles based on focus position information designated by the input interface.

Assignees

• Maxell Ltd

Inventors

• Shimano Takeshi

Classifications

• H04N23/60

  Control of cameras or camera modules · CPC title

• H04N25/00

  Circuitry of solid-state image sensors [SSIS]; Control thereof · CPC title

• G03B15/00

  Special procedures for taking photographs; Apparatus therefor · CPC title

• G02B27/4272

  having plural diffractive elements positioned sequentially along the optical path · CPC title

• G03B41/00

  Special techniques not covered by groups G03B31/00 - G03B39/00; Apparatus therefor · CPC title