Question

What is the disadvantage of the light pen?

(a) It’s shape

(b) They cannot detect positions

(c) Accurate reading

(d) Cannot detect positions within black areas

This question was posed to me in an interview.

This question is from Input Devices topic in division Basic of Computer Graphics of Computer Graphics

Answer 1

Correct answer is (d) Cannot detect positions within black areas

To explain: light pen requires special implementations and sometimes gives false reading due to background lighting in a room.