Hybrid Nanostructure Optical Filter for Near-Infrared Interference

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing electronic devices with image sensors face challenges in effectively managing optical distortion and improving visibility across different wavelength spectra, particularly in reducing near-infrared interference while maintaining high transmittance in the visible spectrum with thin, efficient optical filters.

Innovation Solution

A combination structure comprising a hybrid nanostructure array and a light-absorbing layer is introduced, where the hybrid nanostructure array includes a stack of nanostructures with different refractive indices, and the light-absorbing layer is configured to absorb near-infrared wavelengths, achieving high absorption and low transmittance in the near-infrared spectrum while maintaining high transmittance in the visible spectrum, all within a thin thickness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a conventional optical filter is used to block near-infrared light, then near-infrared absorption is improved, but visible spectrum transmittance deteriorates

Engineering Contradiction:

Improvenear-infrared interferenceVSAvoidvisible spectrum transmittance

Core Design Contradiction:

Object-affected harmful factorsVSIllumination intensity

Solution Approach 1:

The optical filter is segmented into multiple distinct layers, each with specific optical properties. The first layer (with positive refractive index) and second layer (with negative refractive index) are separated into discrete structural components, allowing independent optimization of each layer's thickness and material composition to achieve selective wavelength transmission

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent employs composite material structures combining materials with different refractive index characteristics. By integrating a material with positive refractive index and a material with negative refractive index in a layered configuration, the filter achieves enhanced spectral selectivity, blocking near-infrared while maintaining visible light transmission

Inventive Principle:

Principle #40Composite materials

2Object-affected harmful factors

If the optical filter thickness is increased to improve near-infrared blocking, then near-infrared absorption is improved, but device complexity and size increase

Engineering Contradiction:

Improvenear-infrared blockingVSAvoidfilter thickness

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The patent changes the fundamental optical parameters of the filter layers by introducing materials with negative refractive index. This parameter change enables achieving equivalent or superior near-infrared blocking performance with reduced layer thickness compared to conventional positive refractive index materials alone

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The layered structure with negative refractive index materials serves multiple functions simultaneously: it blocks near-infrared wavelengths while maintaining visible spectrum transmission. This multi-functionality is achieved within a single integrated filter structure, reducing the need for additional separate components

Inventive Principle:

Principle #6Universality (Multi-functionality)

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 solution effectively increases transmittance in the visible spectrum and reduces transmittance in the near-infrared spectrum, providing a selective blocking effect and high light absorption characteristics, suitable for integration into image sensors and camera modules, enhancing image quality by minimizing crosstalk from near-infrared interference.

Implementation Method 1

The light-absorbing layer may include a near-infrared absorbing material configured to absorb light of at least a portion of a near-infrared wavelength spectrum

Methodology Applied

Scientific EffectAbsorption (EM radiation): Absorption (EM radiation)

Implementation Method 2

The second material may have a refractive index that is higher than a refractive index of the first material

Methodology Applied

Scientific EffectRefraction: Refraction

Implementation Method 3

Each hybrid nanostructure of the plurality of hybrid nanostructures may include a stack of a first nanostructure and a second nanostructure

Methodology Applied

Scientific EffectInterference: Interference

Data Source

PatentUS11561331B2Combination structures and optical filters and image sensors and camera modules and electronic devices

Publication Date: 2023.01.24 SAMSUNG ELECTRONICS CO LTD

AI summary

A combination structure includes a hybrid nanostructure array and a light-absorbing layer adjacent to the hybrid nanostructure array. The hybrid nanostructure array includes a plurality of hybrid nanostructures, each hybrid nanostructure includes a stack of a first nanostructure and a second nanostructure. The first nanostructure includes a first material. The second nanostructure includes a second material. The second material has a refractive index that is higher than a refractive index of the first material. The light-absorbing layer includes a near-infrared absorbing material configured to absorb light of at least a portion of a near-infrared wavelength spectrum.