Question 1

The active layer of E-LED is heavily doped with

Accepted Answer

A) zn 
B) eu 
C) cu 
D) sn

Question 2

Determine coupling efficiency into the fiber when GaAs LED is in close proximity to fiber core having numerical aperture of 0.3

Accepted Answer

A) 0.9 
B) 0.3 
C) 0.6 
D) 0.12

Question 3

Internal absorption in DH surface emitter Burros type LEDs is

Accepted Answer

A) cannot be determined 
B) negligible 
C) high 
D) very low

Question 4

Determine the internal quantum efficiency generated within a device when it has a radiative recombination lifetime of 80 ns and total carrier recombination lifetime of 40 ns.

Accepted Answer

A) 20 % 
B) 80 % 
C) 30 % 
D) 40 %

Question 5

Estimate optical power coupled into fiber of DH SLED having emission area of 1.96*10?5, radiance of 40 W/rcm2, numerical aperture of 0.2 and Fresnel reflection coefficient of 0.03 at index matched fiber surface.

Accepted Answer

A) 5.459*10?5 
B) 1.784*10-3 
C) 3.478*102 
D) 9.551*10?5

Exam 17: Led Efficiency and Power Generation in Optical Communication

The active layer of E-LED is heavily doped with

Determine coupling efficiency into the fiber when GaAs LED is in close proximity to fiber core having numerical aperture of 0.3

Internal absorption in DH surface emitter Burros type LEDs is

Determine the internal quantum efficiency generated within a device when it has a radiative recombination lifetime of 80 ns and total carrier recombination lifetime of 40 ns.

Estimate optical power coupled into fiber of DH SLED having emission area of 1.96*10^?5, radiance of 40 W/rcm2, numerical aperture of 0.2 and Fresnel reflection coefficient of 0.03 at index matched fiber surface.