Optical Image Capturing System with Near-Confocal Lens Design
Solution Overview
Problem
Conventional optical systems for portable electronic devices face challenges in capturing high-quality images in low-light environments, particularly in dark conditions, and require IR cut filters that occupy space and are costly, making it difficult to design miniaturized surveillance cameras that can effectively capture both visible and infrared light.
Innovation Solution
The optical image capturing system employs a combination of refractive powers and convex/concave surfaces of four lenses, optimizing the focal lengths for visible and infrared light to achieve a near-confocal effect without IR cut filters, using materials and lens parameters to enhance light intake and image quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If IR cut filters are used to capture visible light, then image fidelity is improved, but device size and cost increase
Solution Approach 1:
The patent removes the IR cut filter from the optical system entirely. By optimizing the lens design with specific refractive indices and curvature radii, the system achieves confocal imaging for both visible and infrared light without requiring the filter, thus reducing device size while maintaining imaging fidelity
Solution Approach 2:
The optical lens is designed to serve multiple functions simultaneously: it captures both visible and infrared light effectively without needing separate filtering mechanisms. The lens structure itself provides the wavelength-selective imaging capability that would otherwise require additional components
2Illumination intensity
If conventional optical systems are designed for high aperture to capture light in dark environments, then light intake is improved, but image quality deteriorates
Solution Approach 1:
The patent optimizes multiple lens parameters including refractive indices (nd1=1.64, nd2=1.70, nd3=1.56, nd4=1.68), curvature radii (R1 through R16), and thickness ratios (0.3≤ΣETP/ΣTP≤1.5) to achieve both high light intake and high image quality. These parameter optimizations enable the system to maintain excellent imaging performance across different aperture settings
Solution Approach 2:
The patent uses a composite lens system with four different lens elements, each made from materials with specific refractive indices. This composite structure allows the system to correct optical aberrations while maintaining high light transmission, achieving both high aperture performance and high image quality
3Measurement precision
If the number of lenses is increased to improve imaging quality, then image quality is improved, but device complexity increases
Solution Approach 1:
The patent combines multiple optical functions into a compact four-lens system. By carefully designing the lens configuration and parameters, the system achieves high imaging quality without requiring additional components, thus maintaining simplicity while improving performance
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 allows for improved imaging quality in both visible and infrared spectrums, reducing the need for IR cut filters and enabling compact, cost-effective surveillance cameras with enhanced brightness and fidelity in low-light conditions.
Implementation Method 1
The optical image capturing system employs a combination of refractive powers and convex/concave surfaces of four lenses, optimizing the focal lengths for visible and infrared light to achieve a near-confocal effect
Data Source
AI summary
An optical image capturing system includes, along the optical axis in order from an object side to an image side, a first lens, a second lens, a third lens, a fourth lens, and a fifth lens. At least one lens among the first to the fifth lenses has positive refractive force. The fifth lens can have negative refractive force. The lenses in the optical image capturing system which have refractive power include the first to the fifth lenses. The optical image capturing system can increase aperture value and improve the imaging quality for use in compact cameras.