This is a set of transmitting and receiving in one of the photoelectric sensors. Detection distance can be adjusted according to the requirements. The sensor has a detection distance by visible light interference small, cheap, and easy to assemble, easy to use, and has other characteristics that can be widely used in robot obstacle avoidance, pipeline piecework, and many other automation products. There are advanced features by using an alcohol detector sensor if there are present alcohol is greater than 50% then