Light Receiving Optics for Multi-Angle Image Quality
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional light receiving apparatuses with pinhole arrays restrict multidirectional light incidence, leading to reduced light utilization efficiency and unfavorable image quality due to out-of-round or oval shaped spots at the periphery, which hinder the achievement of favorable image recognition.
Innovation Solution
A light receiving apparatus comprising a semiconductor substrate with two photodetectors and an optical member featuring distinct optical systems for each photodetector, allowing light to enter and form images with principal rays oriented differently, thereby enhancing light utilization efficiency and image quality without the need for an imaging lens.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a pinhole array is used to select rays with a desired angle of view, then measurement precision is improved, but light utilization efficiency deteriorates
Solution Approach 1:
The patent changes the geometric parameters of the light receiving surface, making it concave with a specific curvature radius (R1) that is 0.05 to 5 times the pinhole array pitch (P1). This curvature modification allows peripheral pinholes to receive light from a wider angular range while maintaining the desired angle of view selection, thereby improving light utilization efficiency without sacrificing measurement precision
Solution Approach 2:
The patent transitions from a flat light receiving surface to a three-dimensional concave surface. This dimensional change enables the peripheral pinholes to capture light from multiple directions by utilizing the curved geometry, effectively adding a spatial dimension to the light collection process and improving both light utilization and image quality
2Device complexity
If pinholes are arranged in a conventional array, then device complexity is reduced, but image quality deteriorates due to out-of-round or oval shaped spots
Solution Approach 1:
The patent modifies the curvature parameter of the light receiving surface (with curvature radius R1 between 0.05 to 5 times the pinhole pitch P1) to correct the optical path differences that cause distorted spot shapes. This parameter optimization ensures that principal rays from all pinholes, including peripheral ones, converge properly on the imaging element, producing circular spots and improving image quality while maintaining the simple pinhole array structure
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution achieves high light utilization efficiency and improved image quality by orienting principal rays differently for each photodetector, enabling a thin and efficient image recognition system with an optical length of 1 mm or less, suitable for applications like fingerprint and iris authentication.
Implementation Method 1
an optical member including at least a first optical system that allows light to enter the first photodetector and a second optical system that allows light to enter the second photodetector
Data Source
AI summary
The present disclosure relates to a light receiving apparatus and an electronic appliance that enable achievement of more preferable image quality. A light receiving apparatus includes: a semiconductor substrate including a first photodetector and a second photodetector arranged within at least substantially a same light receiving plane; and an optical member including at least a first optical system that allows light to enter the first photodetector and a second optical system that allows light to enter the second photodetector. In addition, a first pixel of an image formed at the first photodetector with the light entering the first photodetector through the first optical system is different in orientation of a principal ray on an object side from a second pixel of an image formed at the second photodetector with the light entering the second photodetector through the second optical system. The present technology is applicable to, for example, various authentication devices.