Folded Optical Imaging System for Slim Portable Terminals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical imaging systems for portable terminals face challenges in achieving a slim size while maintaining high resolution, as the thickness of the terminal increases with larger lens diameters.
Innovation Solution
The optical imaging system comprises a first lens group with positive refractive power, a second lens group, and a reflective member with an incident, reflective, and emitting surface, configured to satisfy specific optical parameters such as SD1/SDP, f/SDP, and IMG HT/BFL, allowing for a reduced size and improved image quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the diameters of the plurality of lenses increase to maintain high resolution, then the image quality is improved, but the thickness of the portable terminal increases
Solution Approach 1:
The patent introduces a reflective member that redirects light at an angle, changing the optical path from a linear arrangement to a folded geometry. This allows the optical system to achieve a longer effective focal length and larger lens diameter in a compact terminal thickness direction, resolving the contradiction between image quality and terminal thickness.
Solution Approach 2:
The optical system is divided into multiple lens groups (first lens group with positive refractive power, second lens group with negative refractive power) separated by the reflective member. This segmentation allows each lens group to be optimized independently for specific functions while working together to achieve high image quality within the constrained thickness.
2Measurement precision
If the diameters of the plurality of lenses increase to maintain high resolution, then the image quality is improved, but the device complexity increases
Solution Approach 1:
The reflective member serves multiple functions simultaneously: it acts as a light redirector, a structural separator between lens groups, and a component that enables telephoto imaging capability. This multi-functionality reduces the need for additional separate components, thereby managing device complexity while achieving high image quality.
Solution Approach 2:
The patent employs specific refractive power assignments to lens groups (first group with positive refractive power, second group with negative refractive power) and controlled focal length relationships to optimize the optical system. These parameter optimizations allow high image quality to be achieved with a manageable number of components and controlled complexity.
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 enables a compact optical imaging system with improved image brightness and telephoto performance, while maintaining a reduced size and F-number, thus addressing the challenge of increasing terminal thickness with larger lenses.
Implementation Method 1
a reflective member, disposed between the first lens group and the second lens group, including an incident surface, a reflective surface, and an emitting surface
Implementation Method 2
a first lens group, including one or more lenses, having positive refractive power
Implementation Method 3
The second lens group may have positive refractive power
Data Source
AI summary
An optical imaging system includes a first lens group, including one or more lenses, having positive refractive power; a second lens group including a plurality of lenses; and a reflective member, disposed between the first lens group and the second lens group, including an incident surface, a reflective surface, and an emitting surface. The optical imaging system satisfies 1.3<SD1/SDP<1.7, where SD1 is an effective diameter of an object-side surface of a first lens disposed closest to an object side among the one or more lenses of the first lens group, and SDP is a minor-axis length of the incident surface of the reflective member.