A typical LCD is made up of a number of key components, including the backlight, diffusion panel and LCD panel.
The backlight, made up of fluorescent tubes, is the light source for the LCD. A white diffusion panel redirects and scatters the light evenly to ensure a uniform display.
The LCD panel is made up of several parts: two polarized glass substrates (one horizontal and one vertical) that enclose the layer of liquid crystals and colour filters. TFTs (thin film transistors) are arranged on the glass substrate with each TFT addressing a particular pixel on the screen . and energized through the use of a switching device and storage capacitor at each pixel. The colour filters allow independent control of the red, green and blue sub-components of the pixel, thus enabling the reproduction of all colours in the colour space.
Only a limited number of producers make the LCD panel (i.e., Sharp, Samsung, LG Philips). However, what really differentiates LCD monitor manufacturers is the electronics used within. Take a tour of EIZO's production line here with The Making of a FlexScan Monitor.
See the EIZO Colour Handbook: Chapter 3 for a brief yet vivid and illustrative summary on the principles of the LCD monitor.