Concentric Grating Pattern Modulates Light Intensity for Angle Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing imaging devices with diffraction grating substrates face complications in calculating the angle of incidence of light due to complex spiral grating patterns, leading to decreased light transmissivity and interference noise from overlapping concentric circular grating patterns.
Innovation Solution
A single concentric grating pattern with a pitch inversely proportional to the distance from the center is formed on a substrate, and the light is modulated by another similar grating pattern, allowing for image acquisition through a two-dimensional Fourier transform, reducing noise and maintaining light efficiency without a lens.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a special diffraction grating substrate with spiral or concentric circular grating patterns is used to obtain incident angle information, then the angle of incidence can be detected, but the calculation becomes complicated and the pattern complexity increases
Solution Approach 1:
The patent divides the imaging system into two separate functional components: a diffraction grating substrate for light separation and an image sensor for detection. This segmentation allows the grating pattern to be simple while the calculation complexity is handled separately in software, resolving the contradiction between measurement capability and device complexity.
Solution Approach 2:
The patent replaces complex mechanical/optical calculation methods with computational algorithms. Instead of using complex grating patterns that require complicated inverse problem calculations, the system uses a simple grating pattern combined with computational image processing to determine incident angles, substituting mechanical complexity with software-based solutions.
2Measurement precision
If diffraction grating substrates with overlapping concentric circular grating patterns are used, then incident angle information can be obtained, but light transmissivity decreases and interference noise increases
Solution Approach 1:
The patent extracts only the essential function of the diffraction grating (separating light by angle) without using overlapping concentric circular patterns. By removing the unnecessary overlapping pattern complexity, the system maintains incident angle detection capability while significantly improving light transmissivity and eliminating interference noise.
Solution Approach 2:
The patent converts the potential harm of simple grating patterns (insufficient angle information) into a benefit by combining them with computational algorithms. The simple grating pattern allows high light transmissivity, and the computational processing compensates for the simplified optical structure, ultimately improving overall system performance.
3Measurement precision
If diffraction grating substrates with overlapping concentric circular grating patterns are used, then incident angle information can be obtained, but mutual interference between patterns generates noise in the reproduced image
Solution Approach 1:
The patent removes the overlapping concentric circular grating patterns that cause interference noise, keeping only the essential diffraction function. This extraction eliminates the source of mutual interference between patterns while preserving the ability to detect incident angles through computational methods.
Solution Approach 2:
The patent converts the limitation of simple grating patterns (potential insufficient information) into a benefit by using computational algorithms to extract incident angle information. This approach eliminates interference noise from overlapping patterns while maintaining or improving measurement precision through software-based analysis.
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
This approach simplifies the calculation of light incidence angles, reduces noise, and enhances light utilization efficiency, making it suitable for maintenance-free applications like vehicle and surveillance cameras.
Implementation Method 1
a special diffraction grating substrate is attached to an image sensor which obtains the image of the outside world by obtaining the incident angle of the incident light by inverse problem calculation from the projection pattern generated by the light passing through the diffraction grating substrate
Data Source
AI summary
An image sensor has a plurality of pixels arranged in an array on an imaging surface and converts a captured optical image into an image signal. A modulator is provided on a light receiving surface of the image sensor and modulates the light intensity using a grating pattern. An image processor performs image processing of the image signal output from the image sensor. The modulator has a grating substrate and a first grating pattern is formed on a first side of the grating substrate adjacent to a light receiving side of the image sensor. The grating pattern is composed of a plurality of concentric circle patterns. Each concentric circle pattern has concentric circles having a pitch which becomes smaller in inverse proportion to the distance from the center thereof. The plurality of concentric circle patterns do not overlap with each other in the grating pattern.