II. Reading and comprehension

Ex.2 Read and translate the text

 

Optical Technology

1. One of the most interesting developments in telecommunication is the rapid progress of optical communication where optical fibers are replacing conventional telephone wires and cables. Just as digital technologies greatly improved the telephone system, optical communication promises a considerable increase in capacity, quality, performance and reliability of the global telecommunication network. New technologies such as optical fibers will increase the speed of telecommunication and provide new, specialized information service. Voice, computer data, even video images, will be increasingly integrated into a single digital communication network capable of processing and transmitting virtually any kind of information.

2. It is a result of combining two technologies: the laser, first demonstrated in 1960, and the fabrication 10 years later of ultra-thin silicon fibres which can serve as lightwave conductors. With the further development of very efficient lasers plus continually improved techniques to produce thin silica fibres of incredible transparency, optical systems can transmit pulses of light as far as 135 kilometers without the need for amplification or regeneration.

3. At present high-capacity optical transmission systems are being installed between many major US cities at a rapid rate. The system most widely used now operates at 147 megabits per second and accommodates 6,000 circuits over a single pair of glass fibres (one for each direction of transmission).

4. This system will soon be improved to operate at 1.7 gigabits per second and handle 24,000 telephone channels simultaneously. A revolution in information storage is underway with optical disk technology.

5. The first digital optical disks were produced in 1982 as compact disks formusic. They were further developed as a storage medium for computers. The disks are made of plastics coated with aluminium. The information is recorded by using a powerful laser to imprint bubbles on the surface of the disk. A less powerful laser reads back the pictures, sound or information. An optical disk is almost indestructible and can store about 1000 times more information than a plastic disk of the same size.

6. One CD-ROM disk (650 MB) can replace 300,000 pages of text (about500 floppies), which represents a lot of savings in databases. A DVD-ROM can hold up to 17 GB, about 25 times an ordinary CD-ROM. For this reason, it can store a large amount of multimedia software and complete full-screen Hollywood movies in different languages. However, DVD-ROMs are «read-only» devices. To avoid this limitation, companies also produce DVD rewritable drives.

 

Ex. 3 Find in the text where it is said about the points given below. Put down the number of the paragraph

1. The first digital optical disk

2. Cd-ROM and DVD-ROM

3. Optical fibers increase the speed of telecommunication

4. A revolution in information storage.

Ex. 4 Find the terms in the text which describes the following. Put down the number of the paragraph.

 a. a flat piece of plastic that stores information

 b. the process of creating sth. more advanced

 c. a large amount of data that is stored in a computer

 d. a group of sth. that works together

e. knowledge or facts

Ex. 5. Give Ukrainian equivalents to the following words and word –combinations. Find them in the text:

1. optional communication

2. digital technologies

3. optical fibers

4. to improve

5.incredible

6. gass fibers

7. digital optical disks

8. to imprint

9. multimedia software

10. read- only devices