Photonics
Photonics Devices & System Overview
What is Optoelectronics /Photonics
Is there any Difference ?
Optoelectronics:
Any device that operates as an electrical-tooptical or optical-to-electrical transducer.
Photonics:
"Photonics" comes from "photon" which is
the smallest unit of light just as an electron
is the smallest unit of electricity. "Photonics
is the generation, process and manipulation
of photon to achieve a certain function.
Why Do We Need Photonics instead of
Electronics?
An “All - Pervasive” Technology
1) Uninhibited light travels thousands of times faster than
electrons in computer chips. Optical computers will
compute thousand of times faster than any electronic
computer can ever achieve due to the physical limitation
differences between light and electricity.
2) Can packed more wavelengths (that is information
channels) into a optical fibre so that the transmission
bandwidth is increased than conventional copper wires.
3) Light encounters no electromagnetic interference than
that of electron in copper wires.
What is a photonic transistor?
• A transistor is a switch that is turned on and off
by signals from other switches. They perform
logic, store information and are the work
horses of digital computing. Photonic
transistors use light to perform the switching
functions that are performed by electronic
transistors in conventional computers.
OPTOELECTRONICS application
Displays.
Display:
alarm clock, TV and video recorder,
microwave cooker and some ovens.
Liquid crystal displays
watches, calculators, telephones,
portable radios, tape and CD players
office machines such as faxes and copiers.
Most laptop computers & Large flat screen TVs have
liquid crystal displays.
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Communications.
A phone call outside local area
To link computers,
outside broadcast TV
cameras,
Banks, Stock Exchange dealing rooms, etc.
Cameras.
Camcorders and Digital still cameras
depend on a high quality multi- component optical
lens.
Entertainment.
TV remote controller
sends a coded infra-red beam to the set. CD
player
uses a laser diode
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Manufacturing.
Lasers are being used for cutting and welding .
Clothes made in large quantity are cut to shape using
a laser.
The gears in car have probably been welded to the
shaft using a laser.
The symbols all over the dashboard have been
produced using a different type of laser to remove the
black overcoat from a colored.
CAREERS INVOLVING
OPTOELECTRONICS
• Optoelectronics Engineer .
• Biological Researcher and Technician
– uses microscopes with video camera attachment .
• Civil Engineer
– uses a laser beam with a theodelite to create a straight line
over long distances to measure the angle of a proposed road
bridge from a reference position.
• Auto focus camera lens designer
– uses computer programs to design the lens, the sensors and
electronics to measure the sharpness of the image to control
the focus, and CAD (Computer Aided Design) to design the
components and housings.
• Heating Engineer
– uses a Thermal Imaging camera to give a high quality
picture showing the temperature distribution across a scene.
• Communications System Installer
– couples optical fibers to electronic systems to route the
information between computers, monitors etc. or to control a
production machine.
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• Conservation Specialist
– uses laser beams to blast away the grime that has built up
on buildings and statues
• Environmental Inspector
– uses a laser beam projected into the smoke plume from a
factory to monitor the levels of the different gases emitted .
• Quality Control Inspector
– uses apparatus which measures the precise color spectrum
of the food product .
• Surgeon
– uses a slip-on device over the patients thumb which
monitors an infra-red beam to continuously measure the
pulse rate. Also inserts a fiber optic endoscope into the
patient with a camera attached.
• Skilled Machinist
– uses various types of laser beam under computer control
e.g. to cut holes finer than a human hair,
treat or decorate the metal surface,
join components together in a vacuum
Technology - SCOPE
Light wave communications
Consumer Photonics
Pervasive computing
Optoelectronics Devices & System
Overview
From System Perspective
System Structure
Optoelectronic Communication System Structure
Optoelectronic Components
Typical Optoelectronic Components
Optoelectronics in
Optical Communication System
• Next figure “Network Example” shows
characteristics of Long-Haul Networks and how
these are tied into the multiple regional backbone
providers for residential, cellular, and corporate
networks.
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Network Example
Substrate Material: Waveguide
Assembly processes are being evaluated to couple the
signal from the waveguide to an active optical
component.
The key issues are component-to-waveguide assembly
methods, equipment to minimize interfacial optical signal
loss, alignment variations, and long-term stability.
Waveguides in PWB Technology
Example of Waveguides in PWB Technology