Computer Screens

It may be amazing to current computer users who are used to small compact LCD monitors. Not only were initial computer monitors large and cumbersome but that the early monitors used by computer enthusiasts were Cathode Ray Monitors that were not color,

Initial vintage monitors were monochrome – one color only not the brilliant color displays that we take for granted today.

Some of these monochrome monitors were green or orange iridescent. Others were similar to a black and white television that is grey scale.

It is taken for granted now by young computer surfers and gamers that television was always “color”, not so.

Initially TV broadcasts were in “black and white “.

Color TV had been developed but the technology but the widespread use did not arise till the early 1970’s and even later in some areas.

The broadcasts were seen as black and white on those sets and color on color sets.

Color TVs could receive programs that were in the black and white mode as well. Sort of the backwards compatibility of the day.

What then would be the difference between the picture qualities of a television set a monitor has vastly greater resolution than standard TV sets.

The TV sets of that time (as opposed to current high end LCD and plasma high definition TVs) were basically 1950’s technology – even the newer color TV sets. .

A monitor’s screen display should be stable and of good quality, since the computer user may sit very close to the monitor and spend many hours reading the display.

If the images are fuzzy (low resolution) or waver constantly, you would have a throbbing headache and wavering eyes in no time.

Monitors have knobs to adjust for clarity. On vintage monochrome monitors these usually include a brightness knob which adjusts the illumination of the entire screen, and a contrast knob which makes the letters lighter or darker in relation to the background screen newer color monitors will have additional adjustments for color.

The question will arise – how did the vintage CRT (Cathode Ray Tube) monitors initially handle the color technology which came later and became the accepted standard.

A typical color monitor screen worked in much the same way as a standard CRT television.

The inside of the picture tube is coated with three different phosphors: red, green and blue.

Phosphors are special chemical compounds that glow with characteristic colors when bombarded a stream of electrons.

The phosphor gets “excited” and thanks to the additive properties of the color wheel the different colored lights resulting get mixed and that all types of combinations of the three primary colors result.

The end result is that virtually any color of the rainbow can be produced.

And as for the color white the eyes play a useful trick. When all three colors are mixed together in equal quantities, the eye sees this as “white light”.

Finally the sharpness of the CRT color monitor or a TV set’s image is determined by three factors: the monitor’s bandwidth, its dot pitch, and the accuracy of its convergence.

Although the bandwidth and dot pitch are important to determine a good monitor, convergence is the real measurement.

Indeed we have come a long way from the initial simple vintage monochrome monitors. What we now take for granted with LCD monitors and indeed our high definition TV sets all originated with simple CRT monochrome monitor technology which was merged with the technology and tricks gleaned from the color TV industry.

We should all be grateful. We owe much to “Uncle Miltie”.