Colour Television

 

Найдите ответы на вопросы в тексте 1

1. What basic components does colour transmission contain?

2. Whai images does a monochrome receiver receive?

3. What images does a colou: receiver receive?

4. How many components does an optical system concen­trate?

5. What are they?

6. What component changes the electron bean density?

 

Text I

Colour television is the transmission and reception of images in full col­our. The colour television system can produce programs both in colour on colour receivers and in black-and-white on monochrome receivers. Also, colour receivers receive monochrome pictures when they are being transmit­ted. Colour transmission contains two basic components — brightness infor­mation and colour information. Red, green, and blue are the colours that are chosen for colour television.

Colour cameras. In a colour camera an optical system separates the red, green, and blue image components of a picture and concentrates these three components in separate but identical colour camera tubes. Thus, the output of one tube reacts to the red light image; another — to the green, and anoth­er — to the blue light image.

Colour kinescope. In a monochrome kinescope a single electron gun produces an electron beam. The brightness is controlled by an electron grid, which changes the electron beam density.

In a colour kinescope three electron guns produce three electron beams which are synchronized. The intensities of beam are controlled by the volt­age corresponding to the green, red, and blue components respectively of the colour picture.

 

 

Найдите ответы на вопросы в тексте 2

1. Why can colour television signals be transmitted over the same dis­tance as monochrome television signals?

2. Why does a colour television re­ceiver require more servicing than a monochrome receiver?

3. Is it possible to convert a black-and-white receiver to receive colour broadcasts?