Backlight

A backlight is a form of illumination used in liquid crystal displays (LCDs). As LCDs do not produce light by themselves (unlike for example Cathode ray tube (CRT) displays), they need illumination (ambient light or a special light source) to produce a visible image. Backlights illuminate the LCD from the side or back of the display panel, unlike frontlights, which are placed in front of the LCD. Backlights are used in small displays to increase readability in low light conditions such as in wristwatches, and are used in computer displays and LCD televisions to produce light in a manner similar to a CRT display. A review of some early backlighting schemes for LCDs is given in a report by Peter J. Wild IEEE First-Hand History under its section Backlit LCDs.

Simple types of LCD displays such as in digital watches are built without an internal light source, requiring external light sources to convey the display image to the user. Most LCD screens, however, are built with an internal light source. Such LCD screens consist of several layers. The backlight is usually the first layer from the back. But in order to create screen images, a mechanism is needed to regulate the light intensity of the screen's pixels. For this, light valves are used that vary the amount of light reaching the target by blocking its passage in some way. The most common element is a polarizing filter to polarize the light from the source in one of two transverse directions and then passing it through a switching polarizing filter, to block the path of undesirable light.

Backlight (film)

Backlight (Portuguese: Contraluz) is a film directed by Fernando Fragata starring Joaquim de Almeida, Evelina Pereira and Scott Bailey. It was the second highest-grossing Portuguese film in 2010.

External links

Backlight at the Internet Movie Database

References

Backlight (documentary program)

Backlight (Dutch: Tegenlicht) is a documentary television series by Dutch public broadcasting organisation VPRO. The first episode of Backlight was broadcast on 8 September 2002.

The series "aims to grasp the quintessence of prominent trends and developments" in the practice of critical journalism, and tries to improve understanding of the intricate inner workings of our modern society.

The series won the Zilveren Nipkowschijf in 2005. The episode "Lockerbie Revisited" won the Prix Europa in the category TV Current Affairs in 2009. The episode "Money & Speed", made for iPad, won the Golden Eye at the Dutch Design Awards in 2011.

VPRO released four documentaries in 2009 and 2010 under a Creative Commons license using the content distribution feature of the Mininova BitTorrent tracker.

Past editions

Past Backlight episodes are also available online: