This is the simple circuit of proximity infrared detector, proximity sensor based infrared. The applications of this circuit are the most varied. Use in front of the door and many uses.
IC1 = LM567
Resistors = 470R, 10K. 1K, 68R
Capacitors = 1uf, 100nf
IR = TX & RX
LED & 9v Battery
The circuit operation is based on emitting a burst of infrared light signals which bounce off the close object is received by another component. When received the system detects proximity with the LED output is activated (shines).
The integrated circuit is a generator / decoder tones that well meets the needs of this design. Both the photo-diode and photo-transistor be situated with unit suitable approach to improve the range. With simple LED reflectors are available scope of the order of meters. With convex lens can cover distances of five meters. It is convenient to sacrifice some range but placing UV filters and SUNLIGHT which do not let the photo-transistor (receiver element) sunlight.