Laptop Displays
Introduction
This page provides details on the various laptop display technologies used with DOS laptop, portable and luggable computers. It should be read in conjunction with the Graphics Cards page as well as my CRT Monitors page for completeness.
These days we take it for granted that our modern laptops have colour high-resolution screens. Back when manufacturers were trying to make the IBM PC or compatible more transportable and lightweight, installing a Cathode Ray Tube (CRT) miniature monitor into a case made it preventatively heavy. CRTs were relatively cheap despite their weight, so it was an obvious choice to use tiny CRTs in their luggable machines. The first portable PCs - the Compaq Portable range - also used a CRT and IBM themselves used one in their first potable, the IBM Portable.
After only a handful of these heavyweights, the PC market turned to Liquid Crystal Display (LCD) technology, and whilst it was hugely expensive to make large LCD screens, as popularity of mobile computing grew prices fell, and so the use of LCDs more or less stuck throughout the DOS era in one guise or another.
Liquid Crystal Display (LCD)
LCD technology was another that first arose in the 1960s. It was tremendously energy-efficient, and required very little space so it suited mobile devices well. Since LCDs don't produce any light themselves (unlike gas plasma), they really needed what was to be called a backlight (literally, a light shining from the back of the screen) to really make the screen more readable. Backlit LCD displays really didn't start to appear until 1988 - before then your laptop computer's LCD display was like a large calculator screen using nothing more than a reflective layer behind the liquid crystals to reflect ambient light! There was also the concept of 'sidelit' displays where rather than shining a light from behind the screen, the display would have a light on each side.
Unfortunately, even with a backlight, LCD displays have poor contrast and a slow refresh rate, which would produce a "ghosting" effect whenever the displayed content was scrolling or moving.
The Toshiba T1100 with its monochrome LCD display (1985)
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