Question

What is an optical transmitter?

Answer 1

Hint: Transmission of information can be defined as exchange of information or message from the sender to the receiver and transmission of information can be done in many ways. The information can be text, data. Voice, images, hand written documents etc. There are different methods of transmission of information and they are modern methods and ancient methods.

Complete answer:
Optical transmitter is a device which converts input signals (electric signals) into light signals (optical signals) in optical transmission. Optical transmitter is classified into an internal and external modulation transmitter based on the modulation method used. In optical transmitters optical sources are used.
Optical transmitter which generates optical signals which in turn encodes the information to be transmitted on the optical signals. Guided-wave or free space optical transmission are the most commonly used optical transmission.
The below diagram shows the guided-wave or free space optical transmission which uses fiber optic cable. Due to the total internal reflection the light rays are trapped inside the fiber optic cable so in this way light rays are transmitted in the fiber optical cable.

The most commonly used source for optical transmitter is LEDs, distributed feedback (DFB) lasers and fabry perot (FP) laser

Note:
Students the sources which are used in an optical transmitter have to satisfy some criteria and the criteria is it has to possess the correct wavelength and be able to modulate to transmit data fastly. In the simplest optical transmitter the binary zeros and ones are sent. LEDs have lower power outputs then the laser.