HOOGHLY ENGINEERING AND TECHNOLOGY COLLEGE
REPORT ON
LASER
NAME : Rohit Mondal
SESSION : 2024-2028
SUBJECT NAME : Physics I
SUBJECT CODE : BS PH 101
DEPARTMENT : ME REPORT TOPIC: Laser
YEAR : 1st SEMESTER : 1st
UNIVERSITY ROLL: 17600724003 CLASS ROLL : 6
Table of Contents
SL . NO. CONTENT PAGE NO.
1. Introduction 3
2. Fundamental principles 3
3. Component of laser system 3
4. Laser beam characteristic and type 3
5. Applications of laser 4
6. Conclusion 4
7. References 5
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Introduction to LASER
The turn LASER stands for Light Amplification by Simulated Emission of Radiation.
It is an outgrowth of a suggestion made by Albert Einstein in 1916 that under the
proper circumstances atoms could release excess energy as light either
spontaneously or when simulated by light. German physicist Rudolf Walther
Ladenburg first observe simulated emission in 1928. LASER have revolutionized
technology and science. A laser generates a coherent and focused beam of light
with remarkable precision, intensity and consistency. Its application span diverse
fields including communication ,medicine ,manufacturing ,entertainment and
research
Fundamental principles
Laser emission is shaped by the rule of quantum mechanics, which limit atoms and
molecules to having discrete amount of stored energy that depend on the nature of
the atom or molecule. The lowest energy level of an individual atom occurs when
its electrons are all in the nearest possible orbit or its nucleus. This condition is
called ground state. When one or more of an atom’s electrons have absorbed
energy they can move to outer orbit and the atom is then referred to as being
excited state are generally not stable as electrons drop from higher energy to lower
energy levels they emits the extra energy as light.
When a population inversion(more electrons in an excited state than the ground
state) is achieved a medium amplifies the emitted light a laser beam is produced.
Components of a Laser System
A basic laser system consists of:
1. Gain medium: the substance (solid, liquid or gas) where light amplification
occurs.
2. Energy source: Provide the required energy to excite electrons such as an
electrical current or optical pumping.
3. Optical cavity: Mirrors that reflect light back to the forth through the medium
of amplify it.
Laser Beam Characteristics and Types
Laser light generally differs from other light in being focused in a narrow beam
limited to a narrow range of wavelength and consisting of waves that are in phase
with each other. This properties arise from interaction between the process of
stimulated emission, the resonant cavity the laser medium.
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Types of Lasers
1. Solid-state laser:
Medium – solid crystal like Ruby or doped glass ,
Example: Nd:YAG laser (used in surgeries and materials processing)
2. Gas Laser:
Medium – gases like helium, neon or carbon dioxide.
Example: CO2 laser (used in welding and cutting)
3. Fiber Lasers:
Medium – optical fibers doped with rare earth materials.
Example: high power fiber laser (used in telecommunication and
manufacturing)
4. Semiconductor Laser:
Medium – semiconductor materials like gallium arsenide.
Example: laser diodes (used in barcode scans and optical storage)
5. Excimer Laser:
Medium – a mixture of reactive gases.
Example: Excimer laser (used in eye surgeries like LASIK)
Laser Applications
Laser delivers coherent, monochromatic, well-controlled and precisely directed light
beams. Although laser make poor choice for general purpose illumination, there are
ideal for concentrating light in space time or particular wavelength. For example,
many people were first introduced to laser by concerts in the early 1970s.
Most laser applications fall into one of the few broad categories:
1. Transmission and processing in information
2. Precise delivery of energy
3. Alignment measurement
4. Imaging
This category is covered diverse application from pinpoint energy delivery for
delicate surgery to heavy duty welding and from the mundane alignment of
suspended ceilings to laboratory measurement of atomic properties.
Conclusion
Lasers have transformed countless industries and technology becoming a
cornerstone of modern innovation. From enabling intricate medical procedures to
powering high-speed Internet their versatility and precision make them
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indispensable. The continuous advancement in laser technology promise even
greater applications such as renewable energy and quantum computing as we
explored their potential laser will undoubtedly remain a key driver for technological
progress.
References
1. Textbooks
2. https://www.britannica.com
3. en.wikipedia.org
4. "How Laser-powered Headlights Work"
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