English for Specific Purposes

42 Electronic Engineering

 

GRAMMAR FOCUS: Participles I, II

 

8. In the following sentences find the participles. Name their forms, try to define their functions and translate the sentences into Russian. If you need, help use GRAMMAR FILE 4 (p. 111).

 

1. Particles can interact with light by either absorbing or emitting photons.

 

2. Having developed the ideas, Charles Hard Townes and Arthur Leonard Schawlow, then at Bell Labs, began a serious study of the infrared laser.

 

3. The resonator typically consists of two mirrors between which a coherent beam of light travels in both directions, reflecting back on itself so that an average photon will pass through the gain medium repeatedly.

 

4. Chemical lasers are powered by a chemical reaction permitting a large amount of energy to be released quickly.

 

5. An electrically powered laser is capable of being mounted in an aircraft, ship, or other vehicle because it requires much less space for its supporting equipment than a chemical laser.

 

6. People working with class 3B and class 4 lasers can protect their eyes with safety goggles which are designed to absorb light of a particular wavelength.

 

7. In 1953 Charles Hard Townes produced the first microwave amplifier, a device operating on similar principles to the laser, but amplifying microwave radiation rather than infrared or visible radiation.

 

8. In other cases the application requires the production of pulses having as large an energy as possible.

 

9. Having worked with re-derivation of Max Planck’s law of radiation, based upon probability

 

coefficients for the absorption, spontaneous emission, and stimulated emission of electromagnetic radiation, Albert Einstein established the theoretic foundations for the laser.

 

10. Most types of laser are an inherently pure source of light; they emit near-monochromatic light with a very well defined range of wavelengths.

 

11. On 19 July 2010 an anti-aircraft laser described as the Laser Close-In Weapon System was unveiled at the Farnborough Airshow.

 

12. Being mentioned in Gordon Gould's notes at a conference in 1959, laser implied several possible applications, such as spectrometry, interferometry, radar, and nuclear fusion.

 

13. Gas lasers using many different gases have been built and used for many purposes.

 

14. Possible injuries are more likely to occur to physicians while using multiple laser wavelengths to perform skin treatments.

 

15. When used in Micro Materials Processing lasers find broad application in the development and manufacturing of screens for smartphones, tablet computers, and LED TVs.