Video Projector LCD Panel Temperature Control via Light Modulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional video projectors face excessive temperature loads on some LCD panels due to uneven light emission adjustments based on average picture levels, leading to potential overheating and increased power consumption.
Innovation Solution
A video projector system that includes a modulated light computer to calculate a correction coefficient, adjusting the light emission to reduce temperature loads by controlling the amount of light emitted from the light source towards the LCD panels, using a combination of light source and light shield control based on average level difference parameters.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the amount of light emitted from the light source is controlled in accordance with only the average picture level APL, then the picture contrast is improved and power consumption is lowered, but the temperature load applied to some LCD panels becomes excessively high
Solution Approach 1:
The patent applies local quality by individually controlling the light emission amount for each LCD panel (red, green, and blue panels separately) based on their respective average picture levels and temperature loads, rather than applying a uniform control based on overall APL. This allows each panel to receive appropriate light intensity matched to its specific operating conditions, preventing excessive temperature load on panels with high APL while maintaining picture contrast.
Solution Approach 2:
The patent changes the control parameter from a single overall APL value to individual average picture level values for each color panel (R-APL, G-APL, B-APL). By introducing separate parameter control for each panel, the system can adjust light emission amounts independently to match each panel's actual operating conditions, thereby reducing temperature load while preserving picture quality and contrast.
2Illumination intensity
If the amount of light emitted from the light source is increased to maintain picture brightness, then picture quality is maintained, but power consumption increases
Solution Approach 1:
The patent implements dynamics by continuously adjusting the light emission amount based on the actual average picture levels detected from the video signal. The light source emission is dynamically controlled to match the specific brightness requirements of different scenes, rather than operating at constant high power. This dynamic adjustment maintains picture brightness when needed while reducing power consumption during low-light scenes.
Solution Approach 2:
The patent changes the light emission control parameter from a fixed high level to variable levels based on detected average picture levels for each panel. By using the detected R-APL, G-APL, and B-APL values to dynamically adjust light emission, the system maintains adequate picture brightness for the current scene while minimizing unnecessary power consumption during low-brightness scenes.
Data Source
AI summary
A video projector for displaying a picture based on a video signal. The video projector includes a first LCD panel for red light, a second LCD panel for green light, and a third LCD panel for blue light. A light source emits light toward the first to third LCD panels. A modulated light computer determines a correction coefficient for reducing the amount of light emitted from the light source toward the first to third LCD panels when temperature load of at least one of the first to third LCD panels increases. An emitted light amount control unit corrects the video signal with the correction coefficient and controls the amount of light emitted from the light source toward the first to third LCD panels.