Optical Sensor Lens Layout for Wider Rain Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional optical sensor devices face challenges in widening the detectable range of rain sensors and maintaining detection accuracy for solar radiation sensors, particularly due to limitations in light guidance and detection surface areas, which can lead to reduced detection capabilities for raindrops and solar radiation.
Innovation Solution
The optical sensor device incorporates a rain sensor with multiple light-emitting elements and a light-guide lens portion featuring equalizing portions to distribute light intensity evenly along the x-direction, and a solar radiation sensor with a solar radiation lens portion having a protrusion to maintain detection accuracy even when the solar radiation detection element is miniaturized and inexpensive.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If multiple light-emitting elements are arranged in the x-direction to widen the detectable range, then the detectable range of the rain sensor is improved, but the light intensity distribution becomes uneven along the x-direction
Solution Approach 1:
The patent applies local quality by providing equalizing portions at specific locations (incident portions) of the light-guide lens portion. These equalizing portions have different light transmission characteristics compared to other regions, specifically designed to reduce light intensity from adjacent light-emitting elements. This local modification creates a non-uniform optical property distribution that compensates for the uneven light intensity caused by multiple light-emitting elements, thereby resolving the contradiction between widened detectable range and uniform light intensity distribution.
2Ease of manufacture
If the solar radiation detection element is miniaturized to reduce cost, then manufacturing cost is reduced, but detection accuracy deteriorates
Solution Approach 1:
The patent applies asymmetry by providing a protrusion on the emission surface of the solar radiation lens portion that extends in a specific direction (opposite to the relative movement direction of the light image). This asymmetric structural feature compensates for the reduced detection area of the miniaturized solar radiation detection element by directing and concentrating the light image onto the active detection area, thereby maintaining detection accuracy while allowing the use of smaller, more cost-effective detection elements.
3Illumination intensity
If the equalizing portion reduces light intensity along the z-direction, then light intensity distribution is equalized, but light guidance efficiency decreases
Solution Approach 1:
The equalizing portions are strategically positioned only at incident portions corresponding to adjacent light-emitting elements, rather than uniformly across the entire light-guide lens portion. This localized approach allows the system to equalize light intensity distribution at critical areas where multiple light sources create interference, while preserving the light guidance efficiency in other regions where such equalization is not needed, thus resolving the contradiction between intensity equalization and overall guidance efficiency.
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 effectively widens the detectable range of rain sensors and maintains detection accuracy for solar radiation sensors, ensuring reliable detection of raindrops and solar radiation levels without increasing costs or sensor size.
Implementation Method 1
The light-guide lens portion is an optical component that guides the light emitted from the light-emitting element to a windshield of a vehicle, and guides a reflected light reflected by the windshield to a detection surface of the light-receiving element
Implementation Method 2
The solar radiation lens portion guides the sunlight incident to the windshield to the solar radiation detection element
Implementation Method 3
The light-receiving element detects an intensity of the reflected light guided by the light-guide lens portion
Implementation Method 4
The solar radiation detection element detects an intensity of solar radiation light emitted from the emission surface
Data Source
AI summary
An optical sensor device includes a plurality of light-emitting elements arranged on an arrangement surface to be apart from each other in an x direction perpendicular to a z direction that is a direction connecting an area corresponding to the plurality of light-emitting elements and an area corresponding to a light-receiving element. A light-guide lens portion includes a plurality of incident portions respectively corresponding to the plurality of light-emitting elements and respectively receiving light from the plurality of light-emitting elements. The plurality of incident portions is provided with an equalizing portion configured to equalize intensity of the light incident on the light-guide lens portion along the x direction by reducing the intensity of the light along the z direction out of the light that is emitted from the light-emitting element, while allowing an incident of part of the light emitted from the light-emitting element adjacent to the corresponding light-emitting element.