1. Put the words in the right order to make a sentence:

1. Some, lasers, power, on, applications, of, constant, depend, a, whose, output, over, is, time, beam. 2. The, laser, mechanism, emission, producing, radiation, in, a, of, on, relies, stimulated. 3. The, the, the, of, for, is, process, supplying, called, energy, required, amplification, pumping. 4. Albert, and, Einstein, established, for, the, the, the, theoretic, foundations laser, maser. 5. Solid-state, glass, which, lasers, that, use, a or, rod, is, "doped", with, ions, energy, provide, the, required, crystalline, states. 6. The, emitted, output, beam, through, laser, is, this, mirror.7. The, which, absorbs, some, pump, energy, higher-energy, quantum, raises, electrons, into, gain, medium, states.

8. Particles, emitting, by, can, with, either, absorbing, or, interact, light, photons. 9. The, the, the, process, for, is, of, supplying, energy, required, pumping, amplification, called.

2. Fill in the blanks with the following words:

Device, wavelength, LOSER, coherence, amplitude, pumping, spots, cavity, beam.

1. A laser is a… that emits light. 2. The output laser … is emitted through the mirror. 3. The process of supplying the energy required for the amplification is called….4. A laser consists of a gain medium inside a highly reflective optical…5. The energy is typically supplied as an electrical current or as light at a different….6. Laser beams can be focused to very tiny …, achieving a very high irradiance. 7…., for "light oscillation by stimulated emission of radiation," would have been more correct.8. Temporal … implies a polarized wave at a single frequency. 9. A beam has an instantaneous ….

3. Complete the following sentences, using active vocabulary:

1. Particles can interact with light by … 2. Most practical lasers contain additional elements that affect properties such as … 3. The emitted laser light is notable for its high degree of … 4. Laser beams can be focused to very tiny spots, achieving…

5. … that affect properties such as the wavelength of the emitted light and the shape of the beam.6. …, for "light oscillation by stimulated emission of radiation," would have been more correct. 7. The surrounding mirrors ensure that most of the light makes many passes through … 8. Part of the light that is between the mirrors passes through …

9. Temporal coherence implies a polarized wave at a single frequency whose phase is ...

4. Say if the following statements are true or false:

1. Light of a specific wavelength that passes through the gain medium is not amplified.

2. Laser is light oscillation by stimulated emission of radiation. 3.The gain medium of a laser is a material of controlled purity, size, concentration, and shape. 4. A laser consists of a gain medium inside a highly reflective optical cavity. 5. There are no lasers which are single spatial mode and consequently their light beams diverge more than required by the diffraction limit. 6. The output laser beam is emitted through the optical cavity. 7. Particles of electrons can’t interact with light. 8. A laser consists of a gain medium inside a flash lamp.