Imaging Lens System Thermal Compensation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Small-sized surveillance cameras face challenges in maintaining constant optical performance across varying temperatures, particularly in harsh conditions between -40°C and 80°C, which affects their resolution and functionality, especially with the increasing demand for self-driving vehicles requiring high-resolution imaging.

Innovation Solution

The imaging lens system comprises a specific arrangement of lenses with positive and negative refractive powers and temperature coefficients, including a stop between certain lenses, to maintain consistent optical properties across temperature changes, with refractive index temperature coefficients and thermal expansion coefficients optimized to minimize focal length variations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If conventional lens designs are used in small-sized surveillance cameras, then the camera can be compact, but the optical performance (resolution) changes with temperature between -40°C and 80°C

Engineering Contradiction:

Improvecamera sizeVSAvoidoptical performance stability

Core Design Contradiction:

Volume of moving objectVSReliability

Solution Approach 1:

The patent applies parameter changes by selecting lens materials with specific refractive index temperature coefficients (DTn). The second lens has a positive DTn (5.0-15.0×10^-6/°C) while the third lens has a negative DTn (-20.0 to -8.0×10^-6/°C), creating complementary thermal responses that stabilize overall optical performance across temperature extremes while maintaining compact form factor

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent uses composite material principles by combining lens elements made from different materials with contrasting thermal-optical properties. The second lens uses material with positive refractive index temperature coefficient while the third lens uses material with negative coefficient, creating a composite lens system where thermal expansions and refractive index changes compensate each other to maintain stable imaging performance

Inventive Principle:

Principle #40Composite materials

2Measurement precision

If high resolution is achieved in surveillance cameras, then imaging quality improves, but the lens system becomes more sensitive to temperature changes

Engineering Contradiction:

ImproveresolutionVSAvoidtemperature sensitivity

Core Design Contradiction:

Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The patent changes material parameters by selecting specific refractive index temperature coefficients for high-resolution lens elements. The second lens (positive DTn: 5.0-15.0×10^-6/°C) and third lens (negative DTn: -20.0 to -8.0×10^-6/°C) are designed with precise parameter specifications that allow high resolution while compensating for temperature-induced focal length variations, thereby reducing temperature sensitivity in high-resolution imaging

Inventive Principle:

Principle #35Parameter changes

3Adaptability or versatility

If the focal length is made variable to adapt to different conditions, then versatility improves, but optical performance becomes less stable across temperature ranges

Engineering Contradiction:

Improveimaging adaptabilityVSAvoidfocal length stability

Core Design Contradiction:

Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The patent applies parameter changes by designing the lens system with specific refractive index temperature coefficients that create thermal compensation. The second lens (positive DTn) and third lens (negative DTn) work together to maintain stable focal length across temperature ranges, enabling the camera to adapt to different imaging conditions while preserving optical stability without requiring variable focal length mechanisms

Inventive Principle:

Principle #35Parameter changes

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 solution ensures that the imaging lens system maintains stable optical performance and minimal focal length changes across a wide temperature range, enhancing the camera's resolution and reliability in extreme conditions.

Implementation Method 1

an imaging lens system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens disposed in order from an object side

Methodology Applied

Scientific EffectRefraction: Refraction

Implementation Method 2

refractive index temperature coefficients and thermal expansion coefficients optimized to minimize focal length variations

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Implementation Method 3

one or more of the second to seventh lenses, disposed on an image side of the stop, each has a positive refractive power and a negative refractive index temperature coefficient

Methodology Applied

Scientific EffectRefractive index temperature coefficient effect:

Data Source

PatentUS20240361573A1Imaging lens system

Publication Date: 2024.10.31 SAMSUNG ELECTRO MECHANICS CO LTD

AI summary

An imaging lens system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens disposed in order from an object side, and a stop disposed on an image side of one of the first to sixth lenses, and one or more of the second to seventh lenses, disposed on an image side of the stop, each has a positive refractive power and a negative refractive index temperature coefficient.