Optical Image Capturing Module with Symmetrical Light Paths
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical image capturing modules using composite right-angled prisms suffer from unequal path lengths and large volumes, leading to asymmetrical optical working distances and complex manufacturing processes, which hinder efficient image capturing and alignment.
Innovation Solution
An optical image capturing module comprising four prisms, wavelength-selective coatings, and a beam splitting coating film group, allowing for symmetrical light paths and reduced module size, with methods for aligning and observing upper and lower substrates using specific wavelength ranges to ensure equal optical working distances.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If composite right-angled prisms are used to map two ray paths into the same plane space, then image observation is achieved, but the path lengths of upper and lower ray paths become unequal
Solution Approach 1:
The patent applies asymmetry by using two different types of prisms (right-angled prism and isosceles right-angled prism) with different geometric properties. The right-angled prism has a 90° angle at one corner, while the isosceles right-angled prism has two 45° angles, creating intentional geometric asymmetry that results in unequal optical path lengths for upper and lower ray paths, thereby achieving asymmetrical optical working distances for specialized imaging applications.
2Measurement precision
If composite right-angled prisms with multiple refraction paths are used, then ray path mapping is achieved, but the module size becomes excessively large
Solution Approach 1:
The patent merges two separate prism components (right-angled prism and isosceles right-angled prism) into a single integrated composite prism module. By combining these prisms with different geometric properties into one unified optical component, the design achieves effective ray path mapping while optimizing the overall module volume and reducing the number of separate optical elements required.
Solution Approach 2:
The patent utilizes three-dimensional spatial arrangement and angular orientation of the prisms to achieve ray path mapping. By manipulating light paths through different spatial dimensions and angular reflections within the composite prism structure, the design accomplishes complex ray path control without requiring excessive linear path lengths, thereby reducing overall module size.
3Ease of operation
If liquid crystal optical shutter is added to control image presentation, then separate image control is achieved, but light intensity efficiency is sacrificed
Solution Approach 1:
The patent replaces mechanical or liquid crystal-based optical shutters with a purely optical solution using wavelength-selective filtering. Instead of using liquid crystal shutters that mechanically or electrically control light passage (sacrificing light intensity), the design uses wavelength-selective filters that passively separate and control different wavelength ranges, maintaining high light intensity efficiency while achieving separate image control for upper and lower substrates.
4Adaptability or versatility
If polygonal prism with mechanical turning control is used, then ray path switching is achieved, but device complexity and volume increase
Solution Approach 1:
The patent replaces mechanical turning control of polygonal prisms with a static optical filtering system. Instead of using mechanically movable polygonal prisms that require complex actuation mechanisms to switch between different ray paths, the design employs fixed wavelength-selective filters that passively direct different wavelength ranges along different optical paths, eliminating mechanical complexity while maintaining ray path switching capability.
Solution Approach 2:
The patent introduces wavelength-selective filters as intermediary elements that mediate between different ray paths. These filters act as optical mediators that selectively transmit or block specific wavelength ranges, enabling separate control and observation of upper and lower substrate images without requiring mechanical movement or complex switching mechanisms.
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 provides symmetrical light paths, reducing module size, ensuring equal optical working distances, and improving image contrast and alignment precision, thereby simplifying the manufacturing process and enhancing industrial applications.
Implementation Method 1
a first wavelength-selective medium arranged on the third surface of the second prism, wherein the first wavelength-selective medium reflects light rays at a second wavelength range less than a cut-off wavelength and permits light rays at a first wavelength range greater than the cut-off wavelength to penetrate
Implementation Method 2
a second wavelength-selective medium arranged on the third surface of the third prism, wherein the second wavelength-selective medium permits light rays at the second wavelength range less than the cut-off wavelength to penetrate and reflects light rays at the first wavelength range greater than the cut-off wavelength to penetrate
Implementation Method 3
a beam splitting coating film group having a plurality of coating films, separately arranged between the first surface of the first prism and the second surface of the second prism, between the first surface of the second prism and the second surface of the fourth prism, between the first surface of the fourth prism and the second surface of the third prism, and between the first surface of the third prism and the second surface of the third prism
Data Source
AI summary
A method of aligning an upper substrate and a lower substrate is provided. The upper and lower substrates are oppositely arranged, and the aligning method includes the following steps: providing an optical image capturing module; emitting light rays to a third surface of a first prism; filtering the light rays, so that the light rays are divided into light rays at the first wavelength range and light rays at the second wavelength range, wherein the light rays at the first wavelength range irradiate a pattern on the upper substrate, and light rays at the second wavelength range irradiate a pattern on the lower substrate; reflecting a pattern image on the upper substrate to an image capturing apparatus; reflecting a pattern image on the lower substrate to the image capturing apparatus; and determining locations of the patterns of the upper and lower substrate that are on the image capturing apparatus.