Shadowless Camera Housing Light Pipe Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing camera housing designs for in-vehicle cameras suffer from a shadowing effect due to the partial obstruction of illumination cones by the inner housing portion, leading to non-uniform infrared light distribution, with areas of interest (driver and passenger) receiving lower light levels while the center receives more, resulting in a suboptimal image capturing environment.
Innovation Solution
The design incorporates light pipes to extend from the IR LEDs to an illumination exit plane at the same height as the lens assembly, eliminating shadowing and ensuring even light distribution by using light pipes with total internal reflection and customizable radius and texture to shape and diffuse the illumination cone.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the inner housing portion extends beyond the outer housing portion to accommodate the lens assembly, then the camera housing minimizes the volume it occupies within the passenger compartment, but the illumination cones generated by IR LEDs are partially obscured by the inner housing portion, resulting in a shadowing effect and non-uniform light distribution
Solution Approach 1:
The patent extracts the light transmission function from the housing structure by introducing dedicated light pipes. The light pipes are separate optical components that guide IR light from the LEDs to the illumination exit plane, removing the shadowing problem caused by the inner housing portion while maintaining the compact form factor.
Solution Approach 2:
The light pipes serve as intermediary optical elements between the IR LEDs and the passenger compartment. These light pipes transmit the illumination cones without being obstructed by the inner housing portion, thereby mediating the light path to achieve uniform illumination while preserving the compact housing design.
2Device complexity
If the inner housing portion is positioned to house the lens assembly, then the camera assembly achieves a compact integrated design, but the unshadowed area extending outward from each IR LED is only illuminated by one source, resulting in lower light levels in driver and passenger areas
Solution Approach 1:
The patent segments the illumination function by providing separate light pipes for each IR LED. This segmentation allows each LED's illumination cone to be independently guided to the exit plane without obstruction, ensuring that driver and passenger areas receive adequate light from their respective LEDs while maintaining the integrated compact design.
Solution Approach 2:
The light pipes extend in a dimension perpendicular to the housing thickness, allowing the illumination cones to bypass the shadowing inner housing portion. This dimensional change in the light path enables both LEDs to contribute to illuminating the driver and passenger areas effectively.
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 achieves a uniform and optimal lighting pattern throughout the passenger compartment, enhancing image capture quality by ensuring both driver and passenger areas receive adequate light without central over-illumination, while minimizing the camera's visibility through light pipe design.
Implementation Method 1
The first and second light pipes extend from the circuit board to the front side of the housing such that light is conveyed from the first and second infrared light sources, respectively, to an illumination exit plane of the camera assembly
Data Source
AI summary
A camera assembly includes a circuit board on which an imager is mounted, and a lens assembly mounted over the imager to the circuit board. The camera assembly further includes a first infrared light source mounted on the circuit board at a first location, and a second infrared light source mounted on the circuit board at a second location. A first light pipe is mounted to the circuit board at the first location, while a second light pipe is mounted to the circuit board at the second location. The circuit board, lens assembly, first and second infrared light sources, and first and second light pipes are disposed in a housing, which includes a front housing and a rear housing. The first and second light pipes extend from the circuit board to the front housing such that light is conveyed from the first and second infrared light sources, respectively, to an illumination exit plane of the camera assembly.