OPTO ELECTRONICS - Quiz

1) Which is the combination of photo transistor?

LASER diode and pin diode Photo transistor and DIAC Photo diode and transistor Photo resistor and TRIAC

2) What is the advantage of photo transistors over photo diodes?

Considerably lower sensitivity Limit voltage handling capacity Considerable greater sensitivity Vulnerable to electrical sources

3) What is the use of photo transistor?

Used in comparator circuit Used as light controlled switch Used as oscillator Used as demodulator

4) What is the drawbacks of LDR?

More sensitive Available different sizes and specifications Cannot be used to determine precise light levels Made of low resistance material with few holes

5) Which material is used to make photo resistors (LDR)?

Silicon Germanium Aluminium Cadmium sulfide