Nanostructure Optical Filters for Thin Near-Infrared Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electronic devices with image sensors struggle to effectively manage optical distortion and improve visibility in near-infrared wavelength spectra while maintaining a thin thickness.
Innovation Solution
A combination structure comprising nanostructures with varying dimensions and gaps, combined with a light-absorbing layer, to create a transmission spectrum with multiple peaks in the near-infrared range, enhancing optical properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a conventional optical filter is used to manage near-infrared light, then optical distortion is reduced, but the device thickness increases
Solution Approach 1:
The optical filter is divided into multiple discrete nanostructures (spheres, cylinders, or ellipsoids) arranged in a periodic pattern. Each nanostructure segment contributes to the overall optical filtering effect, allowing the filter to achieve desired near-infrared blocking with reduced thickness compared to conventional continuous-layer filters.
Solution Approach 2:
The patent optimizes key parameters of the nanostructures including their size (diameter or width), spacing (pitch), height, and material composition to control the optical properties. By adjusting these parameters, the filter achieves effective near-infrared blocking while maintaining thin profile and visible light transmission.
2Object-affected harmful factors
If the optical filter thickness is increased to improve near-infrared blocking, then optical distortion is reduced, but visibility in visible spectrum deteriorates
Solution Approach 1:
The nanostructures are designed with specific local properties (size, shape, material) that create wavelength-selective optical responses. The local geometry of each nanostructure is optimized to interact differently with near-infrared versus visible light, allowing selective blocking of harmful wavelengths while maintaining transmission of useful visible light.
Solution Approach 2:
The optical filter employs composite structures combining transparent dielectric materials (such as silicon dioxide, titanium dioxide, or silicon nitride) arranged in periodic nanostructure patterns. This composite approach enables simultaneous achievement of visible light transmission and near-infrared blocking that cannot be realized with single-material conventional filters.
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 structure achieves desired optical properties in near-infrared wavelengths with a thin thickness, improving visibility and reducing optical distortion.
Implementation Method 1
a nanostructure array, and a light-absorbing layer adjacent to the nanostructures
Implementation Method 2
the light-absorbing layer including a near-infrared absorbing material configured to absorb light in at least a portion of a near-infrared wavelength spectrum
Data Source
AI summary
A combination structure includes an in-plane pattern of unit cells, wherein the each unit cell includes nanostructures each having a dimension that is smaller than a near-infrared wavelength and a light-absorbing layer adjacent to the nanostructures and including a near-infrared absorbing material configured to absorb light in at least a portion of a near-infrared wavelength spectrum. The nanostructures are define a nanostructure array in the unit cells, and a wavelength width at 50% transmittance of a transmission spectrum in the near-infrared wavelength spectrum of the combination structure is wider than a wavelength width at 50% transmittance of a transmission spectrum in the near-infrared wavelength spectrum of the nanostructure array.