What is the colour of the light emitted from the led, Electrical Engineering

Assignment Help:

Question:

a) Describe five advantages of LED lighting over conventional incandescent lighting.

b) State two impairments that reduces the radiant flux of a surface-emitting LED. Illustrate one way how any one of these impairments may be addressed?

c) Illustrate how white light can be generated using a blue Gallium Nitride (GaN) LED.

d) Find the composition of the quaternary alloy In1-xGaxAsyP1-y for making semiconductor LEDs operating at 1.27μm. The bandgap energy Eg of the quartenary alloy in eV is then given by the empirical relationship Eg = 1.35 - 0.72y + 0.12y2 where y=2.2x.
e) Given a particular Gallium Nitride (GaN) Edge-emitting LED drawing a current 50 mA when the voltage is 1.5 V and operating at 450 nm wavelength with light power of 5 µW coupled with a 9 µm single-mode fibre.

i) What is the colour of the light emitted from the LED?
ii) Calculate the overall efficiency of the LED.
iii) Calculate its internal quantum efficiency given that Tr = 50ns and Tnr = 70 ns.
iv) Hence, calculate the internal optical power generated by the LED.


Related Discussions:- What is the colour of the light emitted from the led

Energy conservation building codes, Energy Conservation Building Codes ...

Energy Conservation Building Codes It encompass the norms and standards of energy consumption expressed in terms of per square meter of the area wherein energy is used. The

Operation of mosfet, Operation of MOSFET The operation of a metal-oxi...

Operation of MOSFET The operation of a metal-oxide-semiconductor field-effect transistor which is abbreviated as MOSFET can be separated into three modes, depending upon the

Determine the armature current and torque angle, Q. Determine the armature ...

Q. Determine the armature current and torque angle? A 1500-hp, 6600-V, six-pole, 60-Hz, three-phase, wye-connected, synchronous motor, with a synchronous reactance of 36 , neg

Find the average power absorbed by each element, Q. Let v(t) = V max cos ω...

Q. Let v(t) = V max cos ωt be applied to (a) a pure resistor, (b) a pure capacitor (with zero initial capacitor voltage, and (c) a pure inductor (with zero initial inductor curren

Cipper, when i/p voltg is grater than battery diode is clse or open

when i/p voltg is grater than battery diode is clse or open

Self-excited generator, The magnetic field can be supplied by coils supplie...

The magnetic field can be supplied by coils supplied from the output of the generator itself. This is known as self-excitation.There are three ways that the field coils can be conn

Background of energy conservation, Background of Energy Conservation ...

Background of Energy Conservation As a thumb rule, the energy needs of a country are about 1.5 times its GDP or the economic growth rate. India's projected growth rate up to

Switched mode power supply , Switched Mode Power Supply  (SMPS) Switch...

Switched Mode Power Supply  (SMPS) Switching mode power  supply converts an unregulated DC voltage  to a regulated DC  output  voltage . SMPS  stands  for switched mode  power

Determine the voltage across each resistor, For the circuit of Fig: (i) ...

For the circuit of Fig: (i) using Kirchoff's Laws , find all the currents (ii)  determine the voltage across each resistor and check that all loops comply with KVL (iii

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd