Seven-Lens Optical System for Compact Low-Light Imaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional miniaturized lenses have weak dark-light photographing capability, failing to meet the imaging needs of dark-light scenes such as night scenes and starry skies due to their small aperture and weak imaging quality.
Innovation Solution
An optical system comprising seven lenses with specific refractive powers and surface configurations, including a first lens with positive refractive power and convex object-side surface, a seventh lens with negative refractive power and concave image-side surface, and satisfying the relation TTL/ImgH<1.3, along with an aperture diaphragm and aspheric lens surfaces, to enhance light convergence and correct aberrations, ensuring a large aperture and good imaging quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If the lens is miniaturized to reduce total length, then the device size is reduced, but the aperture becomes small and dark-light photographing capability deteriorates
Solution Approach 1:
The optical system is divided into seven separate lens elements with different refractive powers and surface configurations. This segmentation allows each lens to contribute specifically to either miniaturization (negative power lenses) or light gathering (positive power lenses with large curvature radii), resolving the contradiction between small size and large aperture capability
Solution Approach 2:
Different lens elements have different local optical properties: the first lens has a large object-side curvature radius for light gathering, while the seventh lens has a large image-side curvature radius for controlling aberrations. This local differentiation allows the system to achieve both compact size and excellent dark-light performance
2Length of moving object
If the lens is miniaturized to reduce total length, then the device size is reduced, but the imaging quality deteriorates
Solution Approach 1:
The seven-lens segmented structure allows specific lens elements (third, fifth, and seventh lenses with negative power) to be dedicated to aberration correction, while others focus on imaging. This division of functional responsibility maintains high imaging quality despite the compact overall size
Solution Approach 2:
The patent employs aspheric surfaces on multiple lens elements and carefully controls curvature radii, thicknesses, and refractive indices. These parameter optimizations enable the compact seven-lens system to correct various aberrations effectively and maintain excellent imaging quality
3Manufacturing precision
If more lens elements are added to improve imaging quality, then the imaging definition is enhanced, but the total length increases
Solution Approach 1:
The patent uses aspheric surfaces on the first, third, fourth, fifth, and seventh lenses, along with carefully optimized curvature radii and thicknesses. These parameter changes enable seven lens elements to achieve excellent imaging definition without requiring additional length, as the aspheric surfaces correct aberrations more efficiently than spherical surfaces would
Solution Approach 2:
The seven-lens segmentation with alternating positive and negative power elements creates a compact telecentric design where each element contributes to both imaging and aberration correction, achieving high definition in a short total length
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 optical system achieves improved dark-light photographing performance and high-definition imaging by maintaining a small total length, enhancing brightness and correcting aberrations, thus meeting the needs of slim electronic devices in dark-light environments.
Implementation Method 1
the first lens has positive refractive power, with an object-side surface being convex at the optical axis and an image-side surface being concave at the optical axis; the second lens has positive refractive power, with an object-side surface being convex at the optical axis; the third lens has negative refractive power
Data Source
AI summary
The present disclosure relates to an optical system, an image capturing apparatus and an electronic apparatus. The optical system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens in sequence from an object side to an image side along an optical axis. The first lens has positive refractive power, with an object-side surface being convex at the optical axis and an image-side surface being concave at the optical axis. The second lens has positive refractive power, with an object-side surface being convex at the optical axis. The third lens has negative refractive power, with an object-side surface being convex at the optical axis and an image-side surface being concave at the optical axis. The fifth lens has positive refractive power. The seventh lens has negative refractive power.