An improved large area-type optical sensor using frosted glass

A new area-type optical sensor with position detection function is developed. Area-type optical sensors are used widely today. However it is not cost-effective to develop a large sensor with semiconductor material. In our previous work, an optical sensor with a large sensing area using frosted glass has been developed for easy operating remote controller system. This sensor is low cost, but it is used only as a simple switch because it can only judge whether the light is irradiated or not. Therefore, several sensors are needed according to the number of different operations. Thus we propose a new area-type sensor by consisting of frosted glass and four photo detectors. This sensor is low cost and has a large sensing area. The proposed sensor can detect the position where the light is irradiated on the frosted glass. In addition, this sensor also can be used as a pointing device because the movement of the light on the frosted glass can be judged.