REPUBLIC OF SERBIA

MINISTRY OF DEFENCE

www.mod.gov.rs

MINISTRY OF DEFENCE

Material Resources Sector

Defensive Technologies Department

Military Technical Institute

www.vti.mod.gov.rs

Liquid Crystal Display LED backlights: Semiempiric light management modeling

Branko Livada

Luxell Technologies Ltd., Toronto, Canada, blivada@luxell.com

Abstract: Backlight is neccessary for the operation of the LCD displays. Light sources are core backlight components. There are many types of light sources applicable for backlighting. Advances in the LED  light efficacy, life time and production yield,  resulted in their increased application in the backlights. A short overview of the LED backlight design consideration is provided. LED backlight design process is described. The simplified semiempiric calculation model is established. The model use a  flexible arhitecture building blocks approach that allows a  simplified calculation of some design parameters and application of empirically known data. The model  provides  integral display light management, in design phase. Also,the  model allows integration of   some comertial software simulation  results and experimattally collected design relevatnt daat, as well. The model is applied for well known 3ATI display backlight design and  results are compared with commercial software TracePro application. An excelent compliance of the calculation results is found, and confirmed through measurements.

Keywords: Liquid Crystal Displays, Display backlight, AMLCD technology, LED backlight, light management.