US-12627876-B2 - Imaging device

US12627876B2US 12627876 B2US12627876 B2US 12627876B2US-12627876-B2

Abstract

An imaging device having a lens, an optical sensor and an aperture placed close to the lens, the aperture is constituted by a liquid crystal aperture, which has a first substrate, a second substrate and a liquid crystal layer therebetween; a lower layer electrode, an interlayer insulating layer, and an upper layer electrode are formed in this order on the first substrate; the upper layer electrode having a first electrode, which is formed in an area which includes a center of the pattern area, and a second electrode disposed from the first electrode with a space, a columnar spacer is formed between the first electrode and the second substrate in a plan view.

Inventors

Hirondo Nakatogawa
Yoshiro Aoki
Hitoshi Tanaka

Assignees

JAPAN DISPLAY INC.

Dates

Publication Date: 20260512
Application Date: 20240909
Priority Date: 20230920

Claims (12)

1 . An imaging device having a lens, an optical sensor that receives light, and an aperture placed close to the lens and placed between the lens and an object to be imaged, the aperture being constituted by a liquid crystal aperture in which a liquid crystal layer is sandwiched between a first substrate and a second substrate, a pattern area, and a peripheral light shielding frame, a lower layer electrode, an interlayer insulating layer, and an upper layer electrode being formed in this order on the first substrate, the upper layer electrode having a first electrode, which is formed in an area which includes a center of the pattern area, and a second electrode disposed from the first electrode with a space, wherein the space and the lower layer electrode overlap in a plan view, a first light shielding film constituting the peripheral light shielding frame is formed in a periphery of the second substrate, and a first columnar spacer is formed between the first light shielding film and the first substrate in a plan view, a second columnar spacer is formed between the first electrode and the second substrate in a plan view.
2 . The imaging device according to claim 1 , wherein the second columnar spacer is not formed between the upper layer electrode and the second substrate except an area in which the first electrode is formed in a plan view.
3 . The imaging device according to claim 1 , wherein the second columnar spacer is black.
4 . The imaging device according to claim 1 , wherein a second light shielding film is formed on the second substrate overlapping the first electrode on the first substrate in a plan view.
5 . The imaging device according to claim 4 , wherein an outer edge of the second light shieling film is located inside of an outer edge of the first electrode in a plan view.
6 . The imaging device according to claim 5 , wherein the second columnar spacer overlaps the second light shielding film in a plan view.
7 . The imaging device according to claim 1 , wherein the first electrode and the second electrode constitute parts of an encoded aperture pattern.
8 . The imaging device according to claim 1 , wherein the second electrode is divided into a plurality of electrodes.
9 . The imaging device according to claim 1 , wherein a common electrode is formed on the second substrate, and liquid crystal molecules are driven by electric field formed between the upper layer electrode and the common electrode when a first pattern is formed in the pattern area.
10 . The imaging device according to claim 1 , wherein a common electrode is formed on the second substrate, and liquid crystal molecules are driven by electric field formed between the lower layer electrode and the common electrode when a second pattern is formed in the pattern area.
11 . An imaging device having a lens, an optical sensor that receives light, and an aperture placed close to the lens and placed between the lens and an object to be imaged, an outer shape of the aperture being rectangular, the aperture being constituted by a liquid crystal aperture in which a liquid crystal layer is sandwiched between a first substrate and a second substrate, a pattern area, and a peripheral light shielding frame, wherein the pattern area is a pentagon or larger polygon or circle, in the pattern area, scanning lines extend in a first direction and are arranged in a second direction, video signal lines extend in the second direction and are arranged in the first direction, a pixel is formed in a region surrounded by the scanning lines and the video signal lines, a pitch of the pixel in the first direction is 30 μm or less, and a pitch of the pixel in the second direction is 30 μm or less, in the pattern area, a columnar spacer, which determines a distance between the first substrate and the second substrate, is formed in a first area which includes a center of the pattern area, and in the first direction, a width of the first area is 30% or less of a width of the pattern area.
12 . The imaging device according to claim 11 , wherein in the second direction, a width of the first area is 30 or less of a width of the pattern area.

Description

CROSS-REFERENCE TO RELATED APPLICATION The present application claims priority from Japanese Patent Application JP 2023-152255 filed on Sep. 20, 2023, the content of which is hereby incorporated by reference into this application. BACKGROUND OF THE INVENTION (1) Field of the Invention This invention relates to an imaging device using the encoded imaging method. (2) Background Technology Imaging with a camera is a process of capturing a two-dimensional image from the three-dimensional world. In an ordinary camera, the image at the focal point is clear, however as the camera moves away from the focal point, the image becomes blurred. On the other hand, there is a demand for all-image display, which can display a clear image on the entire screen, or to obtain a three-dimensional image. To realize such a demand, information on the distance between each position of the object to be imaged and the lens is required. Non-Patent Document 1 describes a technique to measure and calculate distance information along with camera capture using a specially shaped encoding aperture. Non-Patent Document 2 describes a technique that uses a pair of patterns as the encoding aperture, one is a pattern used to counteract image blurring and the other is a pattern used to acquire distance information. PRIOR ART REFERENCES Non-Patent Documents [Non-Patent Document 1] Image and Depth from a Conventional Camera with a Coded Aperture Anat Levin Rob Fergus et al.[Non-Patent Document 2] Coded Aperture Pairs for Depth from Defocus and Defocus Deblurring Changyin Zhou Stephen Lin Shree K. Nayar SUMMARY OF THE INVENTION As an imaging technique for measuring the distance from the lens to the subject and obtaining distance data to form a three-dimensional image or all-in-focus image simply by taking a picture, there is a method of taking a picture using a specially shaped aperture pattern (hereinafter referred to as “encoded aperture pattern”). In other words, this method enables to measure the distance from the lens to the pixel to be calculated by shooting with this encoded aperture pattern. If this encoding aperture pattern is composed of liquid crystal, the degree of freedom of pattern formation can be increased. In this document, this is also referred to as liquid crystal aperture (LC aperture). The LC aperture has a feature of being much smaller in size than a normal liquid crystal display (LCD). In addition, color images and gray displays are not required; only black and white displays are needed. Instead, a clear difference between the white and black displays is required. In other words, a large contrast is needed between the display and the black display. The task of the present invention is to realize such a liquid crystal aperture suitable for forming encoded aperture patterns. The present invention solves the above problem and the main specific measures are as follows. (1) An imaging device having a lens, an optical sensor that receives light, and an aperture placed close to the lens and between the lens and an object to be imaged; the aperture being constituted by a liquid crystal aperture in which a liquid crystal layer is sandwiched between a first substrate and a second substrate, a pattern area, and a peripheral light shielding frame; a lower layer electrode, an interlayer insulating layer, and an upper layer electrode being formed in this order on the first substrate, the upper layer electrode having a first electrode, which is formed in an area which includes a center of the pattern area, and a second electrode disposed from the first electrode with a space, in which the space and the lower layer electrode overlap in a plan view, a first light shielding film constituting the peripheral light shielding frame is formed in a periphery of the second substrate, a first columnar spacer is formed between the first light shielding film and the first substrate in a plan view, and a second columnar spacer is formed between the first electrode and the second substrate in a plan view.(2) The imaging device according to (1), a common electrode is formed on the second substrate, and liquid crystal molecules are driven by electric field formed between the upper layer electrode and the common electrode when a first pattern is formed in the pattern area.(3) The imaging device according to (1), a common electrode is formed on the second substrate, and liquid crystal molecules are driven by electric field formed between the lower layer electrode and the common electrode when a second pattern is formed in the pattern area.(4) An imaging device having a lens, an optical sensor that receives light, and an aperture placed close to the lens and placed between the lens and an object to be imaged, an outer shape of the aperture being rectangular, the aperture being constituted by a liquid crystal aperture in which a liquid crystal layer is sandwiched between a first substrate and a second substrate, a pattern area, and a peripheral light shielding