IR SENSOR

Based on a simple basic Idea, this proximity sensor, is easy to build, easy to calibrate and still, it provides a detection range of 35 cm (range can change depending on the ambient light intensity and with the help of variable resistance). This sensor can be used for most indoor applications where no important ambient light is present. For simplicity, this sensor doesn't provide ambient light immunity, but a more complicated, ambient light ignoring sensor should be discussed in a coming article. However, this sensor can be used to measure the speed of object moving at a very high speed, like in industry or in tachometers. In such applications, ambient light ignoring sensor, which rely on sending 40 Khz pulsed signals cannot be used because there are time gaps between the pulses where the sensor is 'blind'...

The solution proposed doesn't contain any special components, like photo-diodes, photo-transistors, or IR receiver ICs, only a couple if IR leds, an Op amp, a transistor and a couple of resistors. In need, as the title says, a standard IR led is used for the purpose of detection. Due to that fact, the circuit is extremely simple, and any novice electronics hobbyist can easily understand and build it.

Presented By- SANJEEV SHARMA 

                        [ Studying in EC 2nd Year]
                          
Naraina College Of Engineering & Technology, kanpur