could an incandescant light be used for light wave communication?

Question

Also explain itspossible advantages and disadvantages.

Answer 1

Agree w/above, and to list

Advantages:
Simple to implement, just add a manual switch and operator;
Immunity to electronic interference;
Very long distance possible, such as from one mountain peak to another - limited only be visibility;
Could allow communication between Earth and space with optical aid such as telescopes, Earth/moon comm possible;
Simple maintenance
Some security available via collimation in direction of recipient;

Disadvantages:
Very low bandwidth, less than several hertz
Line-of-sight-only communication

Answer 2

Not really. The reason is that such a lamp produces light because of the heat of the filament, and that filament remains hot, essentially at an even temperature, for the split second during which the flow of electricity (in AC) erverses. This constant (or minuscule variation) light output is what prevent an incandescent light from modulating its output by itself. And no hight speed modulation implies no (or very limited, very slow) message passing capability.
Unless you add a shutter in front of it, but then you have two devices; the light bulb is then just the carrier, not the modulating system, the shutter would be.

Answer 3

That idea went out with the blinking shutter-driven flashers used for ship-to-ship communications during World War II. You always see it in the war movies but the data rate was pitifully slow (even though as a line-of-sight technique the messages were secure). Hot filaments of lamps can not change state fast enough for modern communications needs.

Answer 4

Not realistically. The filament has too much thermal mass to be able to follow fast modulation. LED's, which don't use a thermal process, can follow modulation into the gigahertz range, so are used for the purpose.