Five-Lens Optical Imaging Assembly for Compact Mobile Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Optical imaging lens assemblies for mobile devices face challenges in achieving a combination of long focal length, ultra-thin design, and high resolution simultaneously.
Innovation Solution
The optical imaging lens assembly is designed with a specific configuration that includes a sequence of lenses with carefully optimized refractive powers and surface types, such as a first lens with a positive refractive power, a second lens with a concave image-side surface, a third lens with positive refractive power and convex object-side surface, a fourth lens with refractive power, and a fifth lens, where the Entrance Pupil Diameter (EPD) and Total Lens Length (TTL) ratio is maintained below 2, ensuring reduced astigmatism and distortion while maintaining a large aperture and high imaging quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the focal length is increased to achieve high spatial angular resolution, then the imaging resolution is improved, but the total length of the lens assembly increases
Solution Approach 1:
The lens assembly is divided into five separate lens elements (first lens L1, second lens L2, third lens L3, fourth lens L4, and fifth lens L5), each with specific refractive powers and surface configurations. This segmentation allows the system to achieve a long effective focal length (6.61mm) while keeping the total track length (8.01mm) compact by distributing the optical function across multiple elements rather than requiring a single long focal length lens.
Solution Approach 2:
The patent employs aspheric surfaces on multiple lens elements (first lens L1, second lens L2, third lens L3, fourth lens L4, and fifth lens L5) with specific conic coefficients and higher-order terms. This parameter change from spherical to aspheric surfaces enables better control of light paths, reducing aberrations and allowing the system to achieve high resolution with a compact form factor.
2Illumination intensity
If the aperture is enlarged to increase luminous flux, then the imaging quality is improved, but the lens size and complexity increase
Solution Approach 1:
The patent assigns different refractive powers and surface characteristics to different lens elements: the first lens L1 has positive refractive power with convex object-side surface, the second lens L2 has negative refractive power with concave image-side surface, the third lens L3 has positive refractive power with convex object-side surface, the fourth lens L4 has negative refractive power, and the fifth lens L5 has positive refractive power. This local differentiation of optical properties across the lens assembly enables effective control of light paths and aberrations while maintaining a manageable overall complexity.
3Length of moving object
If the total length is reduced to achieve ultra-thin design, then the portability is improved, but the focal length and imaging quality deteriorate
Solution Approach 1:
The patent arranges five lens elements in a nested configuration along the optical axis with specific spacing: the first lens L1 is positioned at the object side, followed by the second lens L2, third lens L3, fourth lens L4, and fifth lens L5 at the image side. This nested arrangement with optimized air gaps between elements enables the system to achieve a compact total length (8.01mm) while maintaining the effective focal length (6.61mm) and imaging quality through precise positioning of each element.
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 configuration effectively reduces astigmatism and distortion, enhances imaging quality, and allows for a larger aperture within a compact lens design, achieving a balance between optical space enlargement and reduced total length, thereby improving image acquisition in mobile devices.
Implementation Method 1
an optical imaging lens assembly, which sequentially includes from an object side to an image side along an optical axis: a first lens with a refractive power; a second lens with a refractive power, an image-side surface of the second lens is a concave surface; a third lens with a positive refractive power, an object-side surface of the third lens is a convex surface; a fourth lens with a refractive power; and a fifth lens with a refractive power
Data Source
AI summary
The disclosure provides an optical imaging lens assembly, which sequentially includes from an object side to an image side along an optical axis: a first lens (L1) with a refractive power; a second lens (L2) with a refractive power, an image-side surface (S4) of the second lens (L2) is a concave surface; a third lens (L3) with a positive refractive power, an object-side surface (S5) of the third lens (L3) is a convex surface; a fourth lens (L4) with a refractive power; and a fifth lens (L5) with a refractive power. TTL is a distance from an object-side surface (S1) of the first lens (L1) to an imaging surface (S13) of the optical imaging lens assembly on the optical axis, EPD is an Entrance Pupil Diameter of the optical imaging lens assembly, and TTL and EPD satisfy TTL/EPD<2.