I have these infared phototransistors from the local radioshack, and I am having a problem with them detecting all light, and not just infared. They work great, except for that. The problem is, obviously, that it can accept a certain frequency from another (Im having two robots communicate by the way) because all they see is a solid stream of incoming light. I just want to figure out how I'm going to filter out all light but infrared? If anyone has any ideas, I love to hear it!