We are all aware now about the changes that are happening within the world of lighting with the increased penetration of LED technology into the traditional areas. What is not so widely appreciated is the changes that are happening with the new types of LEDs being developed with the specific purpose of backlighting.

Historically LED backlighting has been used to offer long life low power solutions to the illumination of small area LCD panels using a combination of LED technology and the refractive qualities of materials to give an even backlit appearance using a limited number of side emitting LEDs.

The next step will be for LEDs, using similar technology to become the backlight of choice to illuminate large area TFT screens . This will replace the use of fluorescent tubes giving longer life and the improving the efficiency of the widely used TFT screens in both computer and TV applications.

What Selectronic is working on is the many applications for LED backlighting on a larger scale and using LEDs to backlight advertising posters and general signage – an area currently dominated by the use of fluorescent tubes.

The latest products are –

• Larger size PCBs populated with either SMD or through hole LEDs optimised to fit behind legend panels to illuminate legends or screens. Likely applications are panels within Vending Machines, ATMs or retail shelving
• Derived from the use of optimised LED strips laid out evenly on a flat plane. This gives even light over a wide area and avoids the situation of shadow with the screen area. These are particularly aimed at illuminating advertising poster or large area signs. With the LED strips in a fixed back plane this format lends itself to advertising fixings where the LED poster is regular changed
• Based on a T5 direct replacement of the fluorescent tube with an internal LED strip that can either be mounted behind or in some applications optimised to target light across the surface to be illuminated
• An LED side lit backlight optimised for large areas. This technology applies particularly where the power consumption needs to be optimised whilst still retaining high levels of light uniformity. Smaller size advertising legends and ATM header panels are good examples where this technology will be particularly applicable