Display Panel Laser Sensing via Monochromatic Filter
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices, such as LCDs and OLEDs, struggle to enhance the visibility of a laser pointer due to penetration or absorption of the laser into the panel, resulting in poor recognition by the human eye, especially when used as substitutes for beam projectors and screens.
Innovation Solution
Incorporating a light source-sensing circuit with a sensor transistor and a monochromatic color filter pattern in the display panel's inactive areas to sense external light sources, including lasers, while minimizing the impact of external light sources other than lasers, thereby improving laser visibility and sensitivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a laser pointer is used on a display device panel, then the display device can substitute for a beam projector and screen, but the laser visibility is poor because the laser penetrates or is absorbed into the panel
Solution Approach 1:
A light source sensing circuit is introduced as an intermediary component between the laser and the display panel. The sensing circuit detects the laser light and generates a sensing signal, which is then processed to display the laser position on the panel, effectively mediating the interaction between the laser and the display device.
Solution Approach 2:
A monochromatic color filter pattern is disposed on the sensor transistor to selectively transmit laser light while blocking external light sources. The color filter changes the spectral composition of incoming light, allowing only the specific wavelength of the laser to pass through to the sensor, thereby enhancing laser visibility.
2Measurement precision
If a light source sensing circuit is added to sense external light sources, then laser sensing capability is improved, but the device complexity increases
Solution Approach 1:
The light source sensing circuit is merged with the existing display panel structure by disposing the sensor transistor within the inactive area of the sub-pixels. The sensing circuit shares common elements with the display circuitry, such as gate lines and data lines, thereby reducing overall system complexity.
Solution Approach 2:
The sensor transistor serves multiple functions: it acts as both a switching element in the display circuit and a photodetector for laser sensing. The inactive area of the sub-pixel, which would otherwise be unused, is utilized for sensing purposes, making the component serve dual purposes.
3Measurement precision
If the sensor transistor is exposed to external light sources, then it can detect light, but the sensitivity to laser is reduced due to interference from other light sources
Solution Approach 1:
The monochromatic color filter pattern is applied locally to the sensor transistor to create selective light transmission properties. The filter is disposed only on the sensor transistor in the inactive area, allowing it to transmit laser light while blocking external light sources of different wavelengths, thereby improving laser sensing reliability.
Solution Approach 2:
The spectral transmission characteristics of the sensor transistor are changed by introducing the monochromatic color filter. The filter modifies the wavelength-dependent transmission parameter, allowing only the specific wavelength of the laser to reach the sensor while blocking other wavelengths from external light sources.
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 enables better recognition of a laser's position on the display panel by enhancing laser visibility and sensitivity, while reducing the effects of external light sources, thus improving the overall laser sensing performance.
Implementation Method 1
a monochromatic color filter pattern disposed on the sensor transistor
Implementation Method 2
a light source-sensing circuit including a sensor transistor... configured to sense an external light source
Data Source
AI summary
A display panel and display device are provided that may be capable of sensing an external light source, such as a laser. The display device may include a display panel including gate lines, data lines, and sub-pixels defined at intersections between the gate lines and the data lines; a light source-sensing circuit in an inactive area of the sub-pixels to sense an external light source; and a monochromatic color filter pattern disposed on a sensor transistor of the light source-sensing circuit. Thus, the incident amount of an external light source other than a laser can be reduced, and the incident amount of the laser can be increased. Accordingly, it may be possible to decrease an initial off-current caused by an external light source and improve the sensitivity in laser sensing. Thus, the size of the sensor transistor can be reduced and aperture ratio can be increased.