Diffractive Optical Element for Compact Distance Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing distance measuring apparatuses face challenges in miniaturization due to the size and cost of cylindrical lenses, making it difficult to create compact and affordable devices for measuring distances based on the rotation angle of projected light spots.
Innovation Solution
A diffractive optical element with a diffractive grating pattern that twists parallel light to change its angle with respect to the x-axis as it travels, allowing for the measurement of distance based on the tilting of the projected light spot, which is more compact and cost-effective compared to cylindrical lenses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a cylindrical convex lens is used to generate twisted beam for distance measurement, then the measurement precision is maintained, but the device size becomes large and miniaturization is difficult
Solution Approach 1:
The patent replaces the cylindrical convex lens (mechanical optical component) with a diffractive optical element that uses diffraction to generate twisted beam. This substitution enables the same functional effect (twisted beam generation for distance measurement) while significantly reducing the device size, as the diffractive element can be implemented as a compact integrated optical component rather than requiring a large cylindrical lens assembly
Solution Approach 2:
The patent changes the optical parameter from refraction-based beam twisting (cylindrical lens) to diffraction-based beam twisting (diffractive optical element). By modifying the fundamental optical mechanism and using diffraction gratings with specific patterns, the system achieves the same twisted beam effect with a much smaller form factor, enabling miniaturization while maintaining measurement precision
2Measurement precision
If a cylindrical convex lens is used to generate twisted beam, then the distance measurement function is achieved, but the manufacturing cost increases
Solution Approach 1:
The patent substitutes the expensive cylindrical convex lens with a diffractive optical element that can be manufactured using standard diffraction grating fabrication techniques. This replacement reduces manufacturing cost while maintaining the distance measurement function, as diffractive elements can be produced more economically through photolithography and other standard semiconductor fabrication processes
Solution Approach 2:
The patent employs a diffractive optical element that can be manufactured as a cost-effective, potentially disposable component compared to precision cylindrical lenses. The diffractive grating pattern can be mass-produced at low cost, making the overall distance measurement apparatus more affordable while maintaining functional performance
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
Enables precise distance measurement with a smaller and more affordable apparatus, maintaining the same level of precision as traditional methods while reducing the size and cost of the device.
Implementation Method 1
a diffractive optical element provided with a diffractive grating pattern that twists the parallel light
Data Source
AI summary
The present invention provides a small diffractive optical element that emits twisted beam, a small distance measuring apparatus and a distance measuring method using a small diffractive optical element. A diffractive optical element includes a first diffractive grating that twists, in a coordinate space defined by an x-axis, a y-axis and a z-axis, parallel light forming a flat plane parallel to the x-axis and going advance in the z-axis direction so that an angle of the flat plane relative to the x-axis becomes a predetermined angle at a location where the parallel light traveling in the z-axis by a predetermined distance reaches.