What Are Lasers?
Lasers are that device which causes an increase or amplifies the amount of light to create a high-intensity beam which is also directional. Lasers have a pure wavelength or frequency. They are available in various sizes that range from about one-tenth of the diameter of the human hair and up to the size of a large building. The power of laser ranges from nano-watts to trillion watts. Several wavelengths are produced which ranges from infrared to vacuum ultra violet, ultra violet, visible, and soft X-ray spectral region. They also have the ability to produce the shortest burst of light which is of about five million-billionths of a second (5 × 10–15 sec).
Modern Communication Systems
The Lasers are part of many modern communication systems and they also act as probes which create the audio signals from the disk players. They are used in cleaning, removing of materials, heat treatment and cutting in the medical and industrial fields. Lasers are present in the laser guided bombs as the targeting elements and are present in the scanners as the optical source. They are also present in the tools which print the microchips.
The laser light is produced from a special apparatus and it has a special stimulated nature due to which it cannot be used as a light source. The lasers do not produce white light but they produce a light of particular wavelength and color. The word “LASER” stands for Light “Amplification by Stimulated Emission of Radiation”. The process of Stimulated Emission of Radiation was first provided by Einstein which was considered to be a natural process. The process takes place when a beam of light goes by a prepared medium and motivates an atom that are present in the medium to release the light in the specific direction and with the same wavelength like that of an original beam. A laser apparatus is composed of a gain medium, a pumping source that is used to provide energy to the device, an optical cavity, mirror arrangement that is used in the reflection of light in back and forth direction which is also amplified further.