Beam Motion Detector

Im a fan of new electronics so I do not know many things. But I wanted to build an infrared motion detector. Basically I want the issuer to the detector and if the beam is interrupted in some sort of tension would be sent to a conduit and the conduit would be running.

Thats what I do. But I can not know what I need for this project, any help would appreiciated.

Here the emitter and detector
http://www.radioshack.com/product/index.jspaproductId=2049723

The link below leads to the block diagram of a motion detector infrared. It is not difficult because most of the circuit is just a couple of IC. Check it out.

pretty simple!

infrared emitter, generates an infrared light.
IR detector responds to light low freq.

IR detector voltage variations, if you need to detect the voltage change, give yourself a limit and a limit lo hello.

if the detector voltage falls within these limits, it leads to another device that runs on a line, piezo beeper chirp / or what ever.

the IR detector will be protected from ambient sunlight and the issuer may require an external lens to focus the beam. plastic film cans and children magnafing glass.