University:
California State University, Northridge
Course:
COMP 222 | Computer Organization
Academic year:

2024
Views:

34

Pages:

23
Author:

Zoey Chang

LCD Monitors CRT & LCD Monitor History CRT & LCD Monitor History How it all started Monitor Overview • The most-used output device on a computer. • Most desktop displays use a cathode ray tube (CRT). • Laptops use liquid crystal display (LCD), lightemitting diode (LED), and gas plasma or other image projection technology. • Monitors using LCD technologies are beginning to replace CRT. LCD History • Liquid crystals were first discovered in 1888 by Austrian botanist Friedrich Reinitzer. • Melt cholesterol-like substance. • When cooled, the liquid turned blue before finally crystallizing. • RCA made the first experimental LCD in (1968). • Manufacturers have been developing creative variations and improvements since on LCDs. What is Being Used Today? • • • The most popular display today remains CRT. It has been available for more than 70 years. CRTs: 1. Vivid colors and detailed images and text. 2. Cost less than LCD monitors. 3. Continue to evolve. LCD Market Trend • Market for flat screen LCDs grew rapidly during the ‘90s. • Huge success of the laptop computer. • It has still been slow in matching the market share of the CRT. • Color LCDs hit the market in the early ‘90s. • Has only now become popular enough for vendors to mass-produce. From CRT to LCD • CRT – Bulky, heavy, use vacuum tube technology. – Using technology that was developed in the 19th century. • LCD – First LCD laptop monitors were very small due to manufacturing costs. – Light, sleek, energy-efficient, have sharp picture. How Monitors Work • Most use a cathode-ray tube as a display device. • CRT: Glass tube that is narrow at one end and opens to a flat screen at the other end. • Narrow end contains electron guns. – Single gun for monochrome and three guns for color. – Display screen is covered with tiny phosphor dots that emit light when struck by the electron gun. Monitor Classifications • Monochrome: Display two colors, one for the background and one for the foreground. • Gray-Scale: A special type of monochrome monitor capable of displaying different shades of gray. • Color: Can display anywhere from 16 to over 1 million different colors. Sometimes called RGB monitors. Monitor Quality and Resolution • • • • • • Quality: Manufacturers describe quality by dot pitch. Smaller dot pitches mean pixels are closely spaced which will yield a sharper image. Most monitors have dot pitches that range from 0.22mm to 0.39mm. Resolution: Indicates how densely packed the pixels are. Most modern monitors can display 1024x768 pixels. High end models can display 1280x1024. LCD Technology • Used for displays in notebooks, small computers, pagers, phones and other instruments. • Uses a combination of fluorescent-based backlight, color filters, transistors, and liquid crystal to create and illuminate images. • Until recently, was only used on notebook computers and other portable devices. • In 1997, manufactures began to offer full size LCD monitors as alternatives to CRT monitors. IBM Advances in Display Technology • In 1981, IBM introduced the Color Graphics Adapter (CGA) display, able to display 4 colors and max resolution of 320x200. • In 1984, Enhanced Graphics Adapter (EGA) display, able to display 16 colors and resolution of 640x350. IBM Advances in Display Technology (cont.) • In 1987, Video Graphics Array (VGA) display. – Most computers today support the VGA standard. • In 1990, Extended Graphics Array (XGA) display, capable of resolutions 800x600 in true color ( 16.8 million colors) and 1024x768 in 65,536 colors. Pre-IBM Apple II • Released in 1977 • First true “personal computer” • Based on the Apple I design with some additions – Plastic case – Able to display color graphics • Able to display 6 colors at 280x192 resolution. Apple II Control Panel Pre-IBM (cont.) TRS-80 • Developed in late 1970s by Radio Shack. • First product in store history to fetch more than $500. • Monitor was basically an RCA TV with the tuner removed. • Became a direct competitor to the Apple computer. TRS-80 Heath Desktop • One of the first computers designed as complete desktop machines. • Included monitor, floppy disks and keyboard. • Was eventually bought by Zenith. IBM PC-1981 • IBM’s 5150 model introduced in 1981. • The PC featured a 5MHz Intel processor, 18K of memory and an optional color monitor. • Starting price: $1,565 Windows Screen Shots Throughout Time: MS-DOS Windows 3.1 Windows Screen Shots Throughout Time: Windows 98 Windows 2K Windows Screen Shots Throughout Time: Windows XP