Technology

Ambient Light Sensor

▼Human Eye Spectrum

  • High sensitivity: 0.001 Lux
  • Human eye sensory wavelength distribution

Ambient light sensors are widely used in mobile devices such as mobile phones, tablet computers, and notebook computers. They are also used in the cars and TVs. When the indoor lights are dimmed, the pupils of the eyes will be enlarged. If the screen brightness of electronic products is too high, the users may feel uncomfortable.

The ambient light sensor can adjust the brightness of the screen to the brightness acceptable to the human eye, and it can also prolong the battery life. In broad daylight or a bright environment, the backlight needs to be brighter. However, long-term high-brightness display increases power consumption and greatly reduces battery life. The battery life is greatly extended due to the use of the ambient light sensors.

For the LED lighting, the ambient brightness is sensed by the ambient light sensor, and the brightness of the LED lamps is adjusted accordingly, which is not only environmentally friendly, but also saves the number of LEDs used whenever it is possible.

Save the Number of LEDs Used

Adjust the Screen Brightness of Electronic Products

Energy Saving

Extends Battery Life

Color Sensor

Color Temperature (CCT) and CIE color index xyY

Color temperature (unit K)

The RGB color sensors are widely used in mobile devices such as mobile phones, tablet computers, and notebook computers. The RGB sensors detect the three primary colors of R (red), G (green), and B (blue) by the color filtered photo-diodes. The color sensor receives ambient light through photodiodes and detects RGB values.

The structure of the color sensor IC includes Built-in color filter and IR cut filter. Through the calibration algorithm, the RGB output is used to calculate the color temperature of the ambient light, and automatically adjust the white balance of the screen or camera image sensor.   

Ambient light color temperature example

100,000 Lux, 10,000K

0.1 Lux

500 Lux, 6500 K

50 Lux, 2,000K

Proximity Sensor

It is widely used in electronic mobile devices such as mobile phones and tablet computers. PS sensor detects the phone is held by the user's ear during a call. At this time, the system automatically turns off the screen backlight, which can prolong the battery life.

The proximity sensor module includes an infrared Light (IR) transmitter and an ASIC (built-in infrared detector). When the sensor detects that an object is approaching, the amount of reflection is pulled up, exceeds the high threshold of the system and the sensor output NEAR. Conversely, when the object is far away, the amount of reflection is dropped down and exceeds the low threshold of the system, and the sensor outputs FAR.