Introduction to laser
Download as PPTX, PDF2 likes5,745 views
Laser stands for "Light Amplification by Stimulated Emission of Radiation." Lasers emit a powerful, monochromatic, collimated beam of light that is coherent in nature. Lasers have several key characteristics that distinguish them from ordinary light sources: (1) They are highly directional with an angular spread of 1mm/m compared to 1m/m for ordinary light; (2) They have high intensity due to their directionality focusing the beam; and (3) They are highly monochromatic and coherent, with wave trains of the same frequency that are in phase. The first working laser was demonstrated in 1960 by Dr. Theodore Maiman using a ruby crystal.
Introduction to laser
- 1. INTRODUCTION LASER stands for Liht Amplification by Stimulated Emission Radiation What is a LASER? Laser is a device which emits a powerful, monochromatic collimated beam of light. The emitted light waves are coherent in nature.
- 2. DIFF BET ODINARY LIGHT AND LASER S NO Ordinary light Laser beams 1 In ordinary light the angular spread is more In laser beam the angular spread is less. 2 They are not directional They are highly directional. 3 It is less intense It is highly intense 4 It is not a coherent beam and is not in phase It is a coherent beam and is in phase 5 The radiation are polychromatic The radiations are monochromatic 6 Example: Sun light, Mercury vapor lamp He- Ne Laser, Co2 laser
- 3. CHARACTERISTICS OF LASER 1. Directionality : Ordinary light spreads in all directions and its angular spread is 1m/m. But it is found that laser is highly directional and is angular spread is 1mm/m. Intensity: Since an ordinary light spreads in all directions, the intensity reaching the target is very less. But in the case of laser, due to high directionality, the intensity of laser beam reaching the target is of high intense beam.
- 4. Monochromatic: Laser beam is highly monochromatic; the wavelength is single, whereas in ordinary light like mercury vapour lamp, many wavelengths of light are emitted. Coherence: It is an important characteristic of laser beam. In lasers the wave trains of same frequency are in phase, the radiation given out is in mutual agreement not only in phase but also in the direction of emission and polarization.
- 5. DR. T.H.MAIMAN& LUBY LASER