IR distance measurement

[bhan1992]

i want make a circuit that can measure distance about 3-5 meters range. i want to use ir tx and rx. the signal from the rx is then fed to a pic for processing.
how should i create that rx circuit? do i need a op amp in this case? and a diode in between the rx circuit and pic?

 

[jiripolivka]

For such short range ultrasonic range meters are easier to make. Doing it with light needs picosecond pulses and a very fast-response receiver. Check laser distance meters to see how it is done.