Ambient Light Sensors Help Improve LCD Performance

A pair of ambient light sensors from Rohm Co. Ltd. are compatible with any light source, making them well-suited for improving the performance efficiency and visibility of LCDs in mobile phones, TVs, notebook computers, and other applications. The devices allow the systems to make brightness adjustments based on the ambient light. The BH1600FVC analog output version features a two-level output current gain adjustment. The digital-output BH1710FVC incorporates a 16-bit analog-to-digital converter and can measure a wide range of intensities in 1-lux increments. The digital device can directly output the illumination intensity digitally, making it possible to eliminate external operation processing.

Precise control is needed to optimize brightness adjustments. However, the brightness sensitivity range of conventional ambient light sensors differs greatly from that of the human eye. Also, the measurement results of conventional light sensors vary between different light sources, such as sunlight and artificial light. But the BH1600FVC and BH1710FVC feature spectral sensitivity characteristics similar to the photopic luminous efficiency of the human eye, allowing them to measure a broad range of illumination intensities, from darkness to direct sunlight. In addition, the sensitivity is greatly improved, resulting in stable operation.