Nowadays, full screen has become the mainstream trend of mobile phone evolution. The superposition of 5G, multi camera, charging, NFC and other technologies makes the available space of the whole machine become a dime a dozen. By the means of traditional design, these sensors are packaged in the screen, but it will lead to increased module thickness and power consumption. Therefore, how to integrate the sensors into the screen, reduce costs, achieve green energy conservation, and increase the proportion of the screen has become the focus of the major electronics manufacturers.
The ambient light sensor (ALS) can accurately measure the light and shade of the ambient light intensity around the device, and match the displayed brightness with the corresponding ambient light intensity through a series of processing. It can be widely used in mobile phones, tablets, laptops and other electronic devices, mainly including three processes: sensor ambient light intensity monitoring, IC data reading and processing, and backlight adaptive adjustment. The data shows that, among the commonly used electronic devices, the power consumed by the display accounts for up to 30% of the battery power. On the one hand, use of ALS in the device can reduce the power consumption as much as possible by adjusting the backlight current to extend the battery life; On the other hand, it can protect the user's eyes and improve the user experience as much as possible through the adaptive adjustment of the display.
In cell ambient light sensor
By means of LTPS-TFT technology, ambient light and color temperature sensors in the screen can be integrated in the electronic equipment, and the electronic equipment can be used to simultaneously realize real-time detection of ambient light and color temperature. In order to realize the integrated technology in the screen, the ambient light sensor is integrated on the TFT glass, and a group of five sensors are used to detect the ambient light intensity and color temperature respectively. The W sensor is used to monitor the ambient light intensity, the C sensor is used to deduct the backlight and display noise, and the R, G and B sensors are used to detect the color temperature. The display screen can automatically adjust the corresponding display brightness and display color temperature according to the ambient light, so that users can obtain a better visual experience. In addition, integrating the ambient light sensor onto the screen backplane is more conducive to achieving full screen display and can save more space for terminal equipment.
TCL CSOT ambient light sensor integration has realized technology upgrading, and has two advantages of high integration and high precision. In cell technology is used to integrate ambient light and color temperature sensors on TFT glass, and realize ambient light and color temperature monitoring functions at the same time; 0.5 Lux/Step @ 0-300lux brightness monitoring accuracy and ± 250K color temperature monitoring accuracy have achieved the industry's super first-class level.
6.53" Ambient Light Sensor Integrated LTPS
TCL CSOT has exhibited the world's first ambient light sensing integrated screen at DTC (Global Ecological Display Conference) in 2021, 6.53" The ambient light sensor integrated LTPS product adopts the LTPS technology of TCL CSOT, and integrates the ambient light sensor on the backplane to realize real-time detection of external ambient light intensity. At the same time, the screen brightness can be adjusted adaptively according to the ambient brightness, so that users can obtain a better visual experience. It improves the display effect, protects the user's vision health, and further reduces the product's energy consumption. In addition, the ambient light sensor device is integrated into the screen. The screen back panel is also more conducive to the realization of full screen display.
6.67" High precision ambient light sensor is integrated with LCD
The newly developed in-screen integrated ambient light LTPS-LCD by TCL CSOT also made a high profile appearance at this year's International Society for Information Display Annual Display Week (SID2022). Based on the low-temperature polysilicon (LTPS) thin film transistor (TFT) process and the photosensitivity of a-Si, this sensor can be used to accurately detect 0-100K lux in the monitoring range and 0.5 lux/step in the 0-10 lux range, and identify the color temperature range of 3500K~6500K and the detection accuracy of 250K. As one of the leading achievements of TCL CSOT in screen display technology, it fully proves its strong technical strength and extraordinary scientific and technological innovation ability. It is expected that TCL CSOT will make persistent efforts in the field of screen display technology, and establish a new trend of internal display technology with the top level.
