Sorry, I'm new in electronics. The purpose for me to use infra-red sensor is to check if there is any barrier which blocks the passage between the transmitter and the receiver. In the passage, there will be a conveyor belt which transports the ICs (DIP) from one m/c to another m/c for post manufacturing processes. I need a good sensor and connect the output of the sensor to 8051 or other for sensing control in order to count the total number of ICs transported from one m/c to another m/c. I browsered the biggest store in RS and found one term called "Reflective Object Sensor". Is it suitable for my purpose? Any comment to me? The sensors we found in the toilet (e.g. hand dryer, etc) are very good for my project but I don't know where can I buy them as I need a cheap price.