Explain He-Ne Laser under the following heads: Construction – working with Diagram.
He-Ne Laser
Construction:
(i) Active medium:
It is a gas laser, which comprises a narrow quartz tube filled with a mixture of helium and neon gases in the ratio of 10:1 respectively, at low pressure (~0.1 mm of Hg). Ne atoms act as active centers and are responsible for the laser action, while He atoms are used to help in the excitation process. The length of the quartz tube is about 50 cm and the diameter is about 1 cm.
(ii) Optical resonator:
To construct the optical resonator cavity, two parallel mirrors are placed at the ends of the quartz tube one of them is partly transparent while the other is fully reflecting. The spacing between the mirrors is adjusted such that it should be equal to the integral multiple of half-wavelengths of the laser light.
(iii) Pumping system:
The pumping is done through electrical discharge by using electrodes that are connected to a high frequency alternating current source.
Working of He-Ne
It is a four energy level laser system. The electrons produced from electric discharge collide with He and Ne atom and excite them to the higher energy levels He2 and Ne4 at 20.61 eV and 20.66 eV respectively. These two states are metastable so the atoms may stay there for a longer time. They are very close to each other, thus some of the He atoms at He2 state may transfer their energy to ground-state Ne atoms through collisions and excite them to the higher energy level Ne4. The kinetic energy of atoms provides the additional energy of 0.05 eV. Thus, He atoms help to achieve population inversion in Ne atoms.
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Now some of the Ne atoms will decay spontaneously to the lower state Ne3 at 18.70 eV by emitting photons of wavelength 6328 Å. The photons that are moving parallel to the axis of the tube will reflect back and forth by the end mirrors of the rod and stimulate other excited Ne atoms to radiate another photon with the same phase. Thus, due to successive reflections of these photons at the ends of the tube, the number of photons multiplies.
After a few microseconds, a monochromatic, intense, and collimated beam of red light of wavelength 6328 Å emerges through the partially silvered mirror.
The atoms at state Ne3 are unstable and decay spontaneously to a lower state Ne2 and finally, they come to the ground state by losing their remaining energy through collision with the tube walls. He-Ne laser operates continuously.
In this article, we will be discussing the He-Ne laser; its construction, working, properties, uses and applications. We will also touch on the history of lasers and how the He-Ne laser came to be.
What is a He-Ne Laser?
A He-Ne laser is a type of gas laser that uses an electric discharge to produce a beam of light. The name “He-Ne” comes from the fact that it was the first laser to be built using helium and neon as the active gases. He-Ne lasers are now commonly used in a variety of applications, including medical procedures, scientific research, and industrial manufacturing.
He-Ne lasers are relatively simple to construct and operate. They typically consist of a tube filled with a mixture of helium and neon gas, with an electrode at each end. When an electric current is passed through the gas, it produces a beam of light.
He-Ne lasers are highly efficient, with a typical efficiency of around 85%. This means that almost all of the energy used to produce the beam is converted into light, making He-Ne lasers very bright. He-Ne lasers also have a very narrow beam, which makes them ideal for many applications where precision is important.
He-Ne lasers are relatively inexpensive to purchase and operate. They are also rugged and reliable, making them ideal for use in many industrial and scientific applications.
How Does a He-Ne Laser Work?
A He-Ne laser is a type of gas laser that uses an electric discharge to produce light. It is named after its inventors, Drs. Hermann Haken and Nicolaas Bloembergen. He-Ne lasers are the most common type of gas laser.
He-Ne lasers produce a beam of reddish-orange light with a wavelength of 632.8 nanometers (nm). This wavelength is in the visible part of the electromagnetic spectrum. He-Ne lasers are used in many applications, including medical diagnosis and surgery, printing, scanning, and measuring devices.
The He-Ne laser was invented in 1960. It was the first gas laser to be commercially available. Gas lasers are now used in a wide variety of applications.
What are the Properties of a He-Ne Laser?
A He-Ne laser is a type of gas laser that uses helium and neon as its gain medium. Its name comes from the fact that it was the first gas laser to be commercially available. He-Ne lasers are used in a variety of applications, including medical devices, spectroscopy, and laser printing.
One of the most important properties of a He-Ne laser is its wavelength. He-Ne lasers emit light at a wavelength of 632.8 nanometers, which is visible to the human eye. This makes He-Ne lasers ideal for applications where it is important to see the beam, such as alignment or machine vision.
Another important property of He-Ne lasers is their coherence. This means that the waves emitted by the laser are in phase with each other, which allows them to travel long distances without spreading out too much. This property is exploited in interferometry, where He-Ne lasers are used to measure tiny distances and changes in distance.
He-Ne lasers are also known for their low cost and reliability. They are typically much cheaper than other types of lasers with similar properties, and they have a long lifetime (up to 20 years). This makes them ideal for
What are the Uses of a He-Ne Laser?
A He-Ne laser is a type of gas laser that uses helium and neon atoms to produce light. It is the most common type of laser used in scientific and industrial applications. He-Ne lasers are used in a variety of settings, including:
-Medical settings: He-Ne lasers are used for various medical procedures, such as laser surgery, cancer treatment, and vision correction.
-Industrial settings: He-Ne lasers are used for cutting and welding metal, measuring distance, inspecting materials, and more.
-Scientific research: He-Ne lasers are used in various types of scientific research, such as spectroscopy and microscopy.
-Other: He-Ne lasers are also used in military applications, such as target designation and rangefinding.
He-Ne lasers are popular because they are relatively inexpensive to produce and maintain, and they can be used for a variety of applications.
What are the Disadvantages of a He-Ne Laser?
The main disadvantage of a He-Ne laser is that it is relatively weak compared to other types of lasers. This can limit its usefulness in some applications. Additionally, He-Ne lasers require careful alignment and maintenance in order to function properly.
What are the Specifications of a He-Ne Laser?
The specifications of a He-Ne laser vary depending on the type of laser and the manufacturer. However, some common specifications include:
-Power output: The power output of a He-Ne laser is typically between 1 and 100 milliwatts (mW).
-Wavelength: The wavelength of light produced by a He-Ne laser is typically between 632 and 633 nanometers (nm).
-Beam quality: The beam quality of a He-Ne laser is typically measured by the full width at half maximum (FWHM), which is the width of the beam at its halfway point. For He-Ne lasers, the FWHM is typically between 0.5 and 5 millimeters (mm).
-Polarization: The polarization of light produced by a He-Ne laser is typically linear.
-Mode structure: The mode structure of a He-Ne laser is typically single-mode or multimode. Single-mode lasers produce a beam with a very narrow diameter, while multimode lasers produce a beam with a wider diameter.
How Much Does a He-Ne Laser Cost?
When it comes to finding the right He-Ne laser for your needs, cost is always going to be a factor. But how much does a He-Ne laser actually cost? In this blog post, we’ll break down the average cost of a He-Ne laser so you can make an informed decision about what’s right for you.
The average cost of a He-Ne laser is around $1000. However, there are many factors that can affect the price, such as the specific model and features you’re looking for. For example, a more powerful laser will typically cost more than a less powerful one.
Of course, cost isn’t everything. You also need to consider the quality of the laser and the company you’re buying it from. Make sure to do your research before making any decisions so you can be sure you’re getting the best possible product for your needs.
In conclusion, the cost of a He-Ne laser can vary depending on factors like power and features. However, you can expect to pay around $1000 on average. Do your research before making any decisions so you can be sure you’re getting the best possible product for your needs.
Conclusion
The He-Ne laser is a powerful tool that has many uses in industry, medicine, and research. It is relatively inexpensive and easy to construct, making it a popular choice for many applications. Thanks to its simple construction and stable output, the He-Ne laser is an ideal tool for many different purposes.
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