Ams introduces color sensors designed for portable devices

     Ams introduces the TCS3490 color sensor designed for portable devices with light source type sensing ideal for devices that need to operate under different light sources. The TCS3490 smart color sensor can accurately measure color and light intensity, enabling designers to achieve more refined display management and brightness control for portable device displays such as smartphones and tablets.

     This color sensor integrates five channels to measure the relative color temperature (CCT) of light with extreme accuracy. With the proliferation of sensors in today's mobile electronics market, manufacturers of mobile devices such as smartphones, tablets and laptops will be able to use these measurements to dynamically adjust the color palette of the display to provide users with a superior visual experience.

     In addition to the traditional red, green, and blue (RGB) color sensing channels, the sensor includes an infrared measurement channel that reliably detects infrared light from ambient light sources. Whether indoors or outdoors, digital cameras and smartphones can take better photos by adjusting the color temperature of the flash. Color measurement is affected by infrared changes in the light, so the sensor includes a reference (C) photodiode that provides a direct measurement reference to help accurately deduct unwanted residual infrared energy. In addition, the RGBC photodiode incorporates an infrared filter that minimizes the influence of infrared spectral components, further improving the accuracy of color measurement.

     The fifth infrared channel is capable of sensing infrared from 700nm to 1,100nm. Since each light source has its own spectral distribution, including the known ultraviolet, RGB and infrared, the system can identify the type of light source near the user by measuring the channel ratio of infrared to C channel and red to C channel. In smartphone and digital camera applications, this function reliably senses the type of light source, helps optimize white balance Settings, optimizes camera and smartphone flash effects, and improves photo quality.

     By measuring the CCT and brightness (Lux) of ambient light in the system, consumer electronics devices can automatically adjust the tone of the display to achieve the best visual experience in different lighting conditions. By adjusting the tone and hue of the display screen, the device can present a more vivid, more natural, and more stable picture under any changing lighting conditions.

     Four separate analog-to-digital converters (ADCs) each correspond to an RGB channel, and the C channel and infrared channel share a fourth analog to digital converter. The simultaneous sampling of four channels avoids errors in the measurement of CCT and light intensity under rapidly changing lighting conditions. The photodiode of the TCS3490 sensor is arranged in a radiation-like structure, so that light entering from any direction can obtain a consistent effective response, especially light entering from a circular window. When the light measurement or color measurement exceeds a preset threshold, the sensor sends an interrupt signal to the processor to prevent the processor from constantly polling through the I2C interface, helping to reduce the overall system power consumption and extend battery life.

     David Moon, senior market manager for Advanced optical Sensor products at ams, said: "Touch displays in consumer electronics devices are an important point of competition. Manufacturers can make their brands stand out and gain a foothold in the market with smarter display management features. The TCS3490 five-channel color sensor not only gives the display a more vivid and attractive color, but also provides a more comfortable visual experience for the user's eyes in different indoor and outdoor lighting conditions, because the sensor's CCT measurement more closely matches the color and brightness perceived by the human eye."