Backlight Unit Light Sensor Sensitivity via Reflective Mediator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing backlight units for LCD devices face challenges in maintaining color reproducibility due to the varying lifespan and brightness of red, green, and blue LEDs, which affects the light sensor's ability to detect white light intensity, especially when the light sensor is positioned on the sidewall of the light guide plate, leading to reduced light reflection and detection efficiency.
Innovation Solution
A backlight unit design that incorporates a mold frame with a light sensing structure on its sidewall, including a recess and a reflecting member, such as a sheet or adhesive tape with reflective material, to enhance light reflectance and direct light emitted from the light guide plate to the light sensor, thereby improving the sensor's sensitivity and maintaining color reproducibility without increasing the device's thickness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the light sensor is positioned on the sidewall of the light guide plate to detect light emitted from the second surface, then the thickness of the backlight unit increases due to the thickness of the light sensor, but positioning it in the lower part of the second surface reduces light reflection intensity and detection efficiency
Solution Approach 1:
A reflective member is introduced as an intermediary element between the light guide plate and the light sensor. This reflective member redirects light emitted from the second surface of the light guide plate toward the light sensor, enabling effective light detection without requiring the sensor to be positioned on the sidewall, thus maintaining compact thickness while improving detection sensitivity
Solution Approach 2:
The light detection approach transitions from direct sidewall detection to indirect detection through light reflection. By utilizing the reflective member to change the light path dimensionally, the system achieves effective detection without increasing the backlight unit thickness in the vertical dimension
2Measurement precision
If the light guide plate is in contact with the sidewall of the mold frame, then the distance between them is minimized, but the intensity of light reflected by the sidewall and emitted towards the light sensor is reduced
Solution Approach 1:
The reflective member serves as a mediator that intercepts light emitted from the light guide plate and redirects it toward the light sensor. This intermediary element ensures sufficient light intensity reaches the sensor for accurate detection, overcoming the light intensity reduction caused by the light guide plate contacting the mold frame sidewall
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 enhances the light sensor's sensitivity, allowing for accurate detection of white light brightness and maintaining color reproducibility while ensuring the backlight unit's compactness, suitable for applications like laptop computers and monitors.
Implementation Method 1
a light sensing structure formed on a sidewall being in contact with a side of the light guide plate, which reflects the light emitted from the light guide plate and provides the light emitted from the light guide plate to the light sensor
Data Source
AI summary
A backlight unit which includes a structure in which the sensitivity of a light sensor for detecting color reproducibility of white light is increased, and a liquid crystal display (“LCD”) device having the same. The backlight unit includes a light source which generates light, a light guide plate which guides the light incident from the light source, a light sensor which detects the light emitted from the light guide plate and a mold frame which receives the light source, the light guide plate, and the light sensor. The mold frame includes a receiving recess which receives the light sensor, and a light sensing structure formed on a sidewall thereof being in contact with a side of the light guide plate which reflects the light emitted from the light guide plate and provides the light emitted from the light guide plate to the light sensor.