2. WHAT ISOPTO-
ELECTRONICS?
OPTICS- the branch of physical science that deals with the
properties and phenomena of both visible and invisible light and
with vision.
OPTOELECTRONICS-Optoelectronics (or optronics) is the study
and application of electronic devices and systems that source,
detect and control light, usually considered a sub-field
of photonics. In this context, light often includes invisible forms of
radiation such as gamma rays, X-rays, ultraviolet and infrared, in
addition to visible light
4. WAVE -
PARTICLE
DUALITYOF
LIGHT
Quantum theory tells us that both light and matter consists of
tiny particles which have wavelike properties associated with
them. Light is composed of particles called photons, and matter is
composed of particles called electrons, protons, neutrons. It's only
when the mass of a particle gets small enough that its wavelike
properties show up.
5. THE
POSULATES
ONWAVE-
PARTICLE
DUALITYOF
LIGHT
The photoelectric effect is the emission
of electrons when electromagnetic radiation, such as light, hits a
material. Electrons emitted in this manner are called
photoelectrons.The phenomenon is studied in condensed matter
physics, and solid state and quantum chemistry to draw
inferences about the properties of atoms, molecules and solids.
The effect has found use in electronic devices specialized for light
detection and precisely timed electron emission.
*PARTICLE NATURE*
8. THE FEW
EFFECTOF
LIGHTS & IT’S
APPLICATIONS
Photoelectric or Photovoltaic
Here, the light is directly converted into electricity. Solar cells make the best
utilization of this direct conversion effect
Photoconductivity
A material is made more electronically conductive by this electrical phenomenon.
It is achieved by absorbing electromagnetic radiations such as UV light, infrared
and visible light. Generally, it is utilized in Charge Coupled Device (CCD) imaging
sensors.
Stimulated Emission
In this process, an energized molecule is made to interact with a light photon.This
interaction decreases the energy level of photon and results in the liberation or
emission of a matching photon. It is then transferred to an electromagnetic field.
Quantum cascade lasers and laser diodes make use of this process.
Radiative Recombination
In this approach electron transfer occurs in semiconductors from valence to
conducting band. This results in a recombination effect and carrier generation
process that produces light. LED’s employ this principle for light production.