Here we have developed a device using laser torch(transmitter), which can

Transmit light up to a distance of about500 meters and a phototransistor (receiver)

Which receives the light signal exactly in line of sight and results a sound signal

Without loosing data.

Here we have developed a device using sensors which ensures that lights in a
Corridor are switched on when any motion is detected.

Here we have developed a device using laser torch(transmitter), which canTransmit light up to a distance of about500 meters and a phototransistor (receiver)Which receives the light signal exactly in line of sight and results a sound signalWithout loosing data.

Here we have developed a device using sensors which ensures that lights in aCorridor are switched on when any motion is detected.