Plastic Lens with IR-Absorbing Agent for Compact Camera
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional optical image lens assemblies for mobile devices face challenges in filtering infrared lights effectively without increasing the system's volume or number of optical elements, which affects image quality and compactness.
Innovation Solution
An optical image lens assembly with at least one optical lens element made of plastic material containing a long-wavelength light absorbing agent, where the agent is homogeneously mixed and provides refractive power, allowing for aspheric surfaces that absorb infrared lights without the need for an additional IR-cut filter, thus maintaining compactness and high image quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If an IR-cut filter is disposed between the last lens element and the image sensor to filter infrared lights, then the color distortion is prevented, but the volume of the optical system increases and the number of optical elements increases
Solution Approach 1:
The patent combines the infrared light absorption function with the lens element itself by incorporating long-wavelength light absorbing agents into the plastic material of the lens. This merges the filtration function into an existing optical component, eliminating the need for a separate IR-cut filter and thereby reducing the overall optical system volume while maintaining effective infrared light filtering.
Solution Approach 2:
The lens element is designed to serve multiple functions: it provides the necessary optical focusing power while simultaneously absorbing infrared lights through the incorporated long-wavelength light absorbing agents. This multi-functionality eliminates the need for dedicated filtration components, reducing both volume and element count.
2Object-affected harmful factors
If blue glass filters are used to enhance infrared light filtration, then the infrared absorption is improved, but the back focal length increases which is unfavorable for compact size
Solution Approach 1:
The patent changes the material parameters of the lens element by incorporating long-wavelength light absorbing agents into the plastic material. This allows the lens to achieve effective infrared absorption with a thickness that maintains the required back focal length, unlike blue glass filters which require sufficient thickness for absorption but thereby increase the back focal length.
3Manufacturing precision
If a larger number of lens elements are used to enhance image quality, then the aberration correction is improved, but the volume of the optical system increases and the device protrudes from the surface
Solution Approach 1:
The patent merges multiple functions into fewer lens elements. By incorporating long-wavelength light absorbing agents into the plastic material of the lens elements, the filtration function is combined with the optical elements that are already necessary for aberration correction, rather than adding separate filtration components that would increase volume.
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 effectively filters infrared lights, preventing color distortion, reduces the number of optical elements, and maintains compact size, enabling high image quality while avoiding the costs and complexities associated with lens coating technologies.
Implementation Method 1
the long-wavelength light absorbing agent is homogeneously mixed with the plastic material... the optical lens element including the long-wavelength light absorbing agent has refractive power... effectively filters infrared lights
Data Source
AI summary
An optical image lens assembly includes, from an object side to an image side, at least one optical lens element. The optical lens element is made of plastic material and includes a long wavelength light absorbing agent. The long wavelength light absorbing agent is uniformly mixed with the plastic material, wherein the optical lens element has refractive power, and at least one of the object-side surface and the image-side surface thereof is aspheric.