Optical Lens Peripheral Stray Light Reduction via Absorbing Layers

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional optical imaging lenses face challenges in reducing stray light, which affects imaging quality due to poor assembly accuracy and limited effectiveness of existing solutions like light shielding elements or black ink markings.

Innovation Solution

An optical lens design featuring a central region and a peripheral region with at least one light absorbing layer and one optical membrane, where the light absorbing layer and optical membrane are strategically positioned to overlap in the optical axis direction, utilizing materials like TixOy or CrxOy for the absorbing layers and silicon dioxide for the membranes to achieve reduced transmittance and reflectance through destructive interference.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a light shielding element is applied to filter stray light, then stray light is reduced, but assembly accuracy deteriorates

Engineering Contradiction:

Improvestray lightVSAvoidassembly accuracy

Core Design Contradiction:

Object-affected harmful factorsVSManufacturing precision

Solution Approach 1:

The patent extracts the light shielding function from a separate physical component (light shielding element) and integrates it directly into the optical lens through peripheral region treatment. This eliminates the need for separate assembly of light shielding components, thereby resolving the assembly accuracy issue while maintaining stray light filtering capability.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent merges the light shielding function with the optical lens structure itself by treating the peripheral region of the lens. The light shielding layer is combined with the lens in a single integrated component, eliminating interface errors and assembly complexity associated with separate light shielding elements.

Inventive Principle:

Principle #5Merging (Combining)

2Object-affected harmful factors

If black ink is used to mark the edge of the optical lens, then stray light is filtered, but the effect is limited

Engineering Contradiction:

Improvestray lightVSAvoidstray light filtering effectiveness

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent uses a composite structure consisting of multiple layers (light shielding layer, hard coating layer, and optional intermediate layers) instead of a single black ink marking. This multi-layer composite approach provides superior and more reliable stray light filtering compared to conventional single-layer ink marking.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent changes the physical and optical parameters of the light shielding by using materials with specific refractive indices and extinction coefficients. The light shielding layer has an extinction coefficient greater than zero in the visible light range, and the hard coating layer has a refractive index between 1.3-1.7, optimizing the filtering effectiveness across different wavelengths.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If the peripheral region of the lens is treated to reduce stray light, then imaging quality is improved, but transmittance and reflectance must be optimized

Engineering Contradiction:

Improveimaging qualityVSAvoidtransmittance and reflectance optimization

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies different optical properties to different regions of the lens. The peripheral region is specifically treated with light shielding and hard coating layers to reduce stray light, while the central optical region maintains its original transmittance characteristics. This localized treatment optimizes imaging quality without unnecessarily complicating the overall optical path.

Inventive Principle:

Principle #3Local quality

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 effectively reduces stray light by minimizing transmittance and reflectance in the peripheral region, thereby enhancing imaging quality and assembly accuracy.

Implementation Method 1

at least one of extinction coefficients of the at least one first layer and the at least one second layer within a wavelength range of visible light is larger than zero

Methodology Applied

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

Implementation Method 2

Refraction index of the at least one second layer is lower than refraction index of the at least one first layer. The at least one first layer and the at least one second layer are stacked alternatively

Methodology Applied

Scientific EffectInterference: Interference

Data Source

PatentUS9638832B1Optical lens

Publication Date: 2017.05.02 GENIUS ELECTRONICS OPTICAL CO LTD

AI summary

An optical lens includes a lens, at least one light absorbing layer, and at least one optical membrane. The lens has a central region and a peripheral region surrounding the central region. The at least one light absorbing layer and the at least one optical membrane are disposed on the lens, located in the peripheral region and expose the central region. Each optical membranes includes at least one first layer and at least one second layer. Refraction index of the at least one second layer is lower than refraction index of the at least one first layer. The at least one first layer and the at least one second layer are stacked alternatively, and at least one of extinction coefficients of the at least one first layer and the at least one second layer within a wavelength range of visible light is larger than zero.