Five-Lens Optical System Stray Light Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional compact optical systems for portable electronic devices suffer from stray light issues, leading to compromised image quality due to the use of cemented lens elements, which are complex to manufacture and prone to displacement errors.
Innovation Solution
A compact photographing optical system comprising five non-cemented lens elements with specific refractive powers and surface shapes, including aspheric surfaces, arranged to minimize stray light and maximize field of view, with air spaces between elements to avoid manufacturing complexities and improve image quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If cemented lens elements are used, then manufacturing complexity increases and displacement errors occur, but compact size is achieved
Solution Approach 1:
The optical system divides the lens assembly into five independent non-cemented lens elements with air spaces between them, eliminating the need for cementing operations while maintaining compact form factor through precise spacing control
2Object-affected harmful factors
If compact optical system is designed, then field of view is large, but stray light increases reducing image quality
Solution Approach 1:
The patent applies aspheric surfaces specifically to the object-side surface of the first lens element and image-side surface of the fifth lens element, while other surfaces use spherical or aspheric designs, optimizing local light control where most critical for stray light reduction while maintaining overall compact design
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 reduces stray light, enhances imaging quality, and maintains a compact size by optimizing the arrangement and refractive powers of the lens elements, while simplifying the manufacturing process through the use of non-cemented lenses.
Implementation Method 1
The fifth lens element with negative refractive power has a concave image-side surface, wherein the image-side surface of the fifth lens element comprises at least one convex shape in an off-axial region thereon, and an object-side surface and the image-side surface of the fifth lens element are aspheric
Data Source
AI summary
A photographing optical system includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element. The first lens element with positive refractive power has a convex object-side surface. The second lens element with positive refractive power has a convex object-side surface and a concave image-side surface. The third lens element with negative refractive power has a concave image-side surface. The fourth lens element has positive refractive power. The fifth lens element with negative refractive power has a concave image-side surface, wherein the image-side surface of the fifth lens element comprises at least one convex shape thereon, and two surfaces of the fifth lens element are aspheric.