Spectral Filter Meta Device Beam Steering Nanostructures
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing image sensors with spectral filters divided into only three wavelength bands (red, green, and blue) face limitations in improving color expression accuracy and object recognition performance, as they do not effectively utilize more nuanced wavelength divisions.
Innovation Solution
A spectral filter design incorporating a meta device with multiple beam steering regions and nanostructures that adjust the incidence angle of incident light, allowing for various transmission wavelength bands by forming multiple unit filters with different resonance wavelengths, and a structure comprising a first and second resonance structure with distributed Bragg reflectors and a cavity layer, enabling the filter to operate as multiple unit filters with distinct transmission bands.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a spectral filter is designed based on a Fabry-Perot filter with a cavity, then a peak transmission wavelength can be determined by adjusting material and thickness, but the spectral wavelength range is limited by processable materials
Solution Approach 1:
The spectral filter is divided into multiple resonance structures (first resonance structure and second resonance structure), each with different cavity layer thicknesses to handle different wavelength bands. This segmentation allows each structure to be optimized for specific wavelength ranges while collectively covering a broader spectrum, overcoming the material processing limitations of a single Fabry-Perot filter design.
Solution Approach 2:
The patent employs composite material structures including distributed Bragg reflectors (DBR) with alternating high and low refractive index layers, combined with cavity layers of different thicknesses. This composite approach enables the filter to achieve multiple transmission wavelength bands by leveraging the optical properties of different material combinations, thereby expanding the spectral wavelength range beyond what single materials can provide.
2Measurement precision
If an image sensor uses only three wavelength bands (R, G, B), then the structure is simple, but color expression accuracy and object recognition performance are limited
Solution Approach 1:
Each resonance structure is divided into multiple resonator regions (first resonator regions and second resonator regions) with different cavity layer thicknesses, creating multiple unit filters within each resonance structure. This segmentation enables the spectral filter to transmit multiple discrete wavelength bands beyond the traditional RGB three bands, thereby improving color expression accuracy and object recognition performance while maintaining a manageable structural organization.
Solution Approach 2:
The spectral filter is designed to serve multiple functions simultaneously: it acts as a multi-bandpass filter that transmits multiple wavelength bands, serves as a beam steering device that directs light at different angles to different resonator regions, and functions as an integrated optical element for image sensors. This multi-functionality allows the filter to enhance measurement precision without proportionally increasing device complexity.
3Adaptability or versatility
If multiple resonance structures with different cavity layer thicknesses are used, then various transmission wavelength bands can be achieved, but the device complexity increases
Solution Approach 1:
The filter system is segmented into two main resonance structures, each containing multiple resonator regions with specific cavity layer thicknesses. This segmentation strategy allows the complex multi-wavelength function to be broken down into manageable modules, where each resonance structure handles specific wavelength ranges, making the overall device complexity controllable while achieving diverse transmission wavelength bands.
Solution Approach 2:
Multiple resonator regions are nested within each resonance structure, with each resonator region containing a cavity layer of specific thickness. This nested configuration allows multiple wavelength-filtering functions to be integrated within a unified structural framework, reducing the overall device complexity compared to having separate independent filters for each wavelength band.
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 design enhances the spectral filter's ability to capture a broader range of wavelengths, improving color expression accuracy and object recognition performance by allowing for more precise light transmission across multiple bands, effectively addressing the limitations of traditional three-band filters.
Implementation Method 1
a meta device disposed on the first resonance structure, the meta device including a plurality of first beam steering regions, in which an incidence angle of an incident light is adjusted differently to be emitted
Implementation Method 2
each first beam steering region of the plurality of first beam steering regions includes a plurality of nanostructures, each nanostructure of the plurality of nanostructures having a shape dimension corresponding to a sub-wavelength of the incident light
Implementation Method 3
The first resonance structure may include a plurality of first resonator regions that exhibit a first resonance wavelength with respect to a vertically incident light
Implementation Method 4
Spectral filters may be designed based on a Fabry-Perot filter, and a peak transmission wavelength may be determined by adjusting a material and a thickness of a cavity provided in the Fabry-Perot filter
Implementation Method 5
Each of the first reflector and the second reflector may independently include a distributed Bragg reflector (DBR)
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A spectral filter includes a first resonance structure and a meta device disposed on the first resonance structure. The meta device includes a plurality of first beam steering regions, in which an incidence angle of an incident light is adjusted differently to be emitted, wherein each first beam steering region of the plurality of first beam steering regions includes a plurality of nanostructures, each nanostructure of the plurality of nanostructures having a shape dimension corresponding to a sub-wavelength of the incident light.