Glare Level Calculation Using Solid Angle and Distance Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining driver glare caused by light sources become less precise and unreliable at increased distances, leading to unreliable control of glare-reducing measures in vehicles.
Innovation Solution
A method that utilizes a distance detector, such as LIDAR, RADAR, or SONAR, to accurately estimate the distance between the vehicle and light sources, allowing for precise calculation of the solid angle and glare level even at greater distances, thereby improving the estimation of glare levels without increasing vehicle costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If the distance between the camera and the light source increases, then the field of view covers more area, but the glare level calculation becomes less precise and unreliable
Solution Approach 1:
The patent introduces an intermediary variable (solid angle) that bridges the relationship between image area and actual spatial relationship. By calculating the solid angle subtended by the light source at the camera position, the system can accurately determine glare levels regardless of distance, as the solid angle properly accounts for both the apparent size and distance of the light source.
Solution Approach 2:
The patent changes the calculation approach from using only image plane parameters (pixel area) to using solid angle parameters that incorporate three-dimensional spatial relationships. This parameter transformation allows accurate glare calculation at any distance by properly scaling the light source's angular size rather than relying on fixed pixel area thresholds.
2Area of stationary object
If a camera with wide-angle lens is used, then the field of view is larger, but the reliable distance range for glare calculation is limited to less than 20 meters
Solution Approach 1:
The patent transitions from two-dimensional image plane measurements to three-dimensional solid angle calculations. By incorporating the angular dimension and spatial relationships, the system can accurately calculate glare for wide-angle lenses at any distance, not just within limited ranges, because solid angles properly represent the light source's apparent size in three-dimensional space.
3Length of stationary object
If the light source occupies a small portion of the acquired image, then the distance is large, but the solid angle calculation becomes unreliable
Solution Approach 1:
The patent replaces direct image-based mechanical measurement with a computational geometric calculation approach. Instead of relying on pixel area thresholds, the system uses the camera's intrinsic parameters (focal length, sensor size) and the light source's position in the image to compute the solid angle mathematically, which remains accurate regardless of how small the light source appears in the image.
Data Source
Figure 1~3
AI summary
The invention relates to a method for determining a glare level caused by a light source (2) illuminating a driver of a motor vehicle (10), comprising the following steps: - acquiring of an image by an image sensor (15), on which at least part of said light source appears; - estimating a distance (L) separating the motor vehicle from said light source; and - calculating said glare level as a function of said distance. According to the invention, during the estimation step, the distance is estimated taking into account results of measurements performed by means of a detector (16) distinct from said image sensor.