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2. Read and translate the following text into Ukrainian. Cathode ray tube

CRT Computer display pixel array (right).The CRT or cathode ray tube is the picture tube of a monitor. The back of the tube has a negatively charged cathode. The electron gun shoots electrons down the tube and onto a charged screen. The screen is coated with a pattern of phosphor dots that glow when struck by the electron stream. Each cluster of three dots, one of each color, is one pixel.

The image on the monitor's screen is usually made up from at least tens of thousands of such tiny dots glowing on command from the computer. The closer together the pixels are, the sharper the image on screen can be. The distance between pixels on a computer monitor screen is called its dot pitch and is measured in millimeters. Most monitors have a dot pitch of 0.28 mm or less.

There are two electromagnets around the collar of the tube which deflect the electron beam. The beam scans across the top of the monitor from left to right, is then blanked and moved back to the left-hand side slightly below the previous trace (on the next scan line), scans across the second line and so on until the bottom right of the screen is reached. The beam is again blanked, and moved back to the top left to start again. This process draws a complete picture, typically 50 to 100 times a second. The number of times in one second that the electron gun redraws the entire image is called the refresh rate and is measured in hertz (cycles per second). It is common in television or very early computer equipment, to use a technique called interlacing, in which all the odd-numbered lines of an image are traced, and then all the even-numbered lines; the circuitry of such an interlaced display need be capable of only half the speed of a non-interlaced display. An interlaced display, particularly at a relatively low refresh rate, can appear to some observers to flicker, and may cause eyestrain.

3. Find the answers to the questions:

1. What does the abbreviation CRT stand for?

2. How does the CRT work?

3. What is the image on the monitor's screen usually made from?

4. What technique is commonly used in television or very early computer equipment?

5. How does the electron beam move in the tube?

4. Complete the sentences.

1. The CRT or cathode ray tube is …

2. The electron gun shoots …

3. The screen is coated with …

4. The distance between pixels on a computer monitor screen is called …

5. There are two electromagnets around the collar of the tube which …

5. Match the following English words with their Ukrainian equivalents.

Аспектне відношення, редагування, точність відтворення кольору, параметри комп’ютера, відстань між точками, фосфорна точка, електронна пушка, негативно заряджений катод, відхиляти(ся), катодно-променева трубка.

6. True or false statements.

1. The back of the cathode ray tube has a positively charged anode.

2. The screen is coated with a fabric that glows when struck by the electron stream.

3. Most monitors have a dot pitch of 1 m or even more.

4. The beam scans across the top of the monitor from right to left.

5. The number of times in one second that the electron gun redraws the entire image is called the refresh rate and is measured in hertz (cycles per second).

7. Translate from English into Ukrainian.

1. Cathode rays (also called an electron beam or e-beam) are streams of electrons observed in vacuum tubes, i.e. evacuated glass tubes that are equipped with at least two metal electrodes to which a voltage is applied, a cathode or negative electrode and an anode or positive electrode

2. Cathode rays are so named because they are emitted by the negative electrode, or cathode, in a tube.

3. To release electrons into the tube, they first must be detached from the atoms of the cathode.

4. In early vacuum tubes (Crookes tubes) this was done solely by the high electrical potential between the anode and the cathode.

5. In modern tubes this is assisted by making the cathode a thin wire filament and passing an electric current through it.

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