The document summarizes information about light emitting diodes (LEDs). It discusses the introduction and history of LEDs, the different types of LEDs, how LEDs work by emitting light when electrons and holes recombine across the p-n junction, the advantages of LEDs like long life and energy efficiency, some disadvantages like high cost and sensitivity to heat, and common uses of LEDs in entertainment, signage, lighting and more. It concludes by thanking the audience and listing sources for further information.

1. VADODARA INSTITUTE OF ENGINEERING
EEE ACTIVITY WORK
GUIDED BY:RAJAN MODHA
PREPARED BY:KRISHNARAJ MISHRA
MANOJ CHAUHAN
DARSHAN GOHIL
HARSH MISTRY

2. LIGHT EMMITING DIODE

3. FLOW OF PRESENTATION
 INTRODUCTION
 TYPES OF LEDs
 WORKING OF LED
 ADVANTAGES & DISADVANTAGEOF LED
 USES OF LED
 BIBLIOGRAPY

4. INTRODUCTION
A light-emitting diode (LED) is a
two-lead semiconductor light
source.
Nick Holonyck invented LED in
1962.
It is a p–n junction diode that emits
light when activated. LEDs are
typically small (less than 1 mm2)
and integrated optical components
may be used to shape the radiation
pattern.

5. TYPES OF LEDs
Miniature LEDs
High Power LEDs
Application-specific LED lights
Alphanumeric
Lighting LED

6. WORKING OF LED
N-type silicon (red) has extra electrons
(black).
P-type silicon (blue) has extra holes
(white).
Battery connected across the p-n junction
makes the diode forward biased, pushing
electrons from the n-type to the p-type and
pushing holes in the opposite direction.
Electrons and holes cross the junction and
combine.
Photons (particles of light) are given off as
the electrons and holes recombine.

7. ADVANTAGES
Long Life
Energy Efficiency
Ecologically Friendly
Durable Quality
Zero UV radiation
Design Flexibility
Low Voltage
Instant Lighting & Frequent

8. DISADVANTAGES
Expensive
Directional
Sensitive to extreme heat
Causes light pollution
Cause loss of vision as human eyes are
very sensitive.

9. USES OF LED
Entertainment
Events
Signage
Home
Business
Auto/Boat/RV
Art Work

10. BIBLIOGRAPHY
www.electronics.howstuffworks.com
www.explainthatstuff.com/diodes.
www.elprocus.com/light-emitting-diode-led-
working
www.circuitstoday.com
www.edisontechcenter.org
www.brighthubengineering.com
www.eslightbulbs.com

11. Thank You……..