Unit 1 : Light sources and optical fiber

What is a light source?

• converts ac to dc

• converts electrical signal to light

• converts light into electrical signal

• converts visible light to invisible light

Which of the following light source works on the principle of spontaneous emission?

• LED

• PIN

• APD

• LASER

Stimulated emission takes place in which of the following device?

• APD

• LASER

• LED

• PIN

Select the wavelengths used for optical transmission windows

• 1310 nm

• 850 nm

• 1550 nm

• 600 nm

Which of the following is true for an LED? (multiple answers)

• linear output

• low cost

• broad spectral width

• complex drive circuit

For a single mode optical fiber which of the options are correct?

• small core size

• large bandwidth

• only one mode

• all of the above

For a single mode fiber the V-number must be

which of the following is zero dispersion window?

• 850 nm

• 1310 nm

• 1550 nm

• 1600 nm

What is true for a LASER?

• less costly

• simple circuitry

• coherent source

• works on spontaneous emission

what is the wavelength of Red light?

• 400 nm

• 550 nm

• 660 nm

• 700 nm