The most popular way of generating an image on any modern day television is by the use of LCD television technology (liquid crystal display).

The nature of a television image is that it is constantly changing both in colour and in contrast.

To create different levels of brightness and contrast there must be a mechanism to enable and restrict the amount of light passing through the lcd television. All LCD televisions have at the back of the appliance a backlight.

The inherent properties of a crystal will allow this to occur, as firstly a crystal state is cylindrical in nature and therefore has the ability to allow light to pass through; secondly it has a twisted property which can be accentuated dependant on how much electrical charge is submitted. Increase the current and the crystal will tighten and therefore become more opaque in nature. Reduce the current and it will relax and allow more light to pass through. Do be aware though that the complete restriction of light is impossible as a crystal cannot completely inhibit the transfer of light. Also as each pixel is so tightly arranged to the next, even with polarized glass, you do get a cross contamination from one pixel to another. Resultant issue is an inability to achieve a true real black.

To create colour in an lcd tv, the pixel has three coloured sub crystals which are made up of the primary colours (red, green, blue). The relationship between these crystals generates the colour and hue of the pixel ie the contrast ratio.

The liquid crystals are sandwiched between two pieces of polarized glass ” sometimes described as mother glass. The polarization effect of the glass focuses the light source which is how LCD televisions can achieve such razor sharp images. One of these sheets of glass is coated with a special polymer which secures the thousands of crystals required to create an lcd television display.

The driving force of the lcd television is the matrix of transistors which disseminates the information to each of the individual pixels. By distributing the information effectively, the appropriate pixel produces the necessary colour and hue, and as this can be performed upto 100 times a second, this is more than enough to create a very fluid and accurate image.

This is an over simplified description of how an LCD works but it does highlight the most important area, as to how the different brightnesss and various colours are achieved. Television manufacturers are currently in development to introduce high performance light emitting diodes which will further focus the brightness and allow greater control over pixels. This more focussed approach will allow a more full disablement of a pixel and help achieve that true black everyone is striving for plus with the use of coloured diodes the colour palette of an lcd television will be further enhanced to achieve even greater subjective contrast ratios.