LCD screens & LCD monitors

LCD screen
In an LCD (Liquid Crystal Display) screen, the crucial element is the liquid crystal itself - a liquid or semi-liquid material whose molecules behave like crystals when subjected to the influence of an electrical field. Due to their structure, some types of liquid crystal can polarize light - a property used either to allow or restrict the passage of light. LCDs, therefore, consist of one or more layers of liquid crystals sandwiched between or lying on top and blue filters. As a plate is turned on or off, the area controlled by it appears in the display alternately bright or dark leading to the sensation of colour. Modern LCDs are backlit (a panel of light shines through the LCD) to improve visibility and contrast.

LCD monitors
- characterized by their thin profile, light weight, and small footprint, LCD monitors offer the best image quality for reading text and good colour. Off-centre viewing, however, reduces colour accuracy and limits resolution.

- the LCD comprises layers of electrical conductors, polarizing materials, electroluminescent panels, and layers of liquid crystal. Each cell, corresponding to a colour, can be varied in brightness to give a full range of colours.

- a 20x enlargement of an LCD screen at 1,024 line resolution shows crisp demarcation between colours. The image is more stable (does not flicker) than in a CRT monitor.

Polarized light
One type of liquid-crystal changes its orientation according to the electrical field: when the crystals are made to twist (upper row) they attenuate the light passing through; when left to line up [lower row) light passes through with less hindrance.


Steve J. Wilson is living in the United States and is a freelance writer since 2006, in digital photography related topics. If you are interested in some useful Digital Photography Classes, than you are in the right place.

Copyright © Steve J. Wilson, All Rights Reserved. All those who are interested in using this article, please make all the links active.