Distance Measurement Aperture Optimization for Resolution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing object detection device has low resolution due to the divergence angle of the laser beam being equal to or larger than the angle β, which limits its ability to accurately detect objects at a distance.
Innovation Solution
A distance measurement apparatus with a first light source, scanning mirror, and a first light receiving optical system, where the first aperture is disposed on the focal plane of the first focusing optical system, limiting the viewing angle to be smaller than the divergence angle of the first light beam, thereby improving resolution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the aperture diameter D is increased to allow more return light to enter the light receiving element, then the light receiving sensitivity is improved, but the viewing angle increases causing resolution to deteriorate
Solution Approach 1:
The patent applies parameter changes by precisely controlling the aperture diameter D and focal distance d to achieve the specific relationship β ≥ α. This parameter optimization allows the system to simultaneously achieve high resolution (small viewing angle) and high light receiving sensitivity (adequate aperture size), resolving the contradiction between these two requirements.
2Measurement precision
If the focal distance d is increased to reduce the viewing angle and improve resolution, then measurement precision is improved, but the device length and complexity increase
Solution Approach 1:
The patent optimizes the focal distance d to achieve the minimum required value based on the relationship β ≥ arctan(D/d). By calculating and setting d to the minimum necessary value rather than using an excessively long optical path, the system achieves high resolution while keeping the device compact and cost-effective.
3Measurement precision
If the aperture diameter D is decreased to reduce the viewing angle and improve resolution, then measurement precision is improved, but the amount of return light entering the light receiving element decreases
Solution Approach 1:
The patent determines the optimal aperture diameter D by satisfying the inequality β ≥ arctan(D/d), where β is constrained by the divergence angle α of the laser beam. This parameter optimization ensures that the aperture is large enough to capture sufficient return light while maintaining a small viewing angle for high resolution, thereby resolving the contradiction between light quantity and resolution.
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 improved distance measurement apparatus enhances resolution by limiting the angular range of return light that can enter the light receiving element, allowing for more accurate detection of objects over a wider range without the need for a longer optical system, resulting in a compact and cost-effective solution.
Implementation Method 1
The first light receiving optical system includes a first focusing optical system, a first light receiving element, and a first aperture located between the first focusing optical system and the first light receiving element. The first aperture is disposed on a first focal plane of the first focusing optical system.
Implementation Method 2
A first viewing angle of the first light receiving optical system is smaller than a first divergence angle of the first light beam. The first viewing angle is given by arctan (D1/F1).
Data Source
AI summary
A distance measurement apparatus includes a light source, a scanning mirror, and a light receiving optical system. The light source emits a light beam. The scanning mirror scans the light beam. The light receiving optical system receives a return light. The light receiving optical system includes a focusing optical system, a light receiving element, and an aperture located between the focusing optical system and the light receiving element. The aperture is disposed on a focal plane of the focusing optical system. A viewing angle of the light receiving optical system is smaller than a divergence angle of the light beam.