Large panel LED displays are becoming the only way to go if you are looking into signage. From stadium signs to retail marketing and even traffic signs, LED displays are being implemented into designs in an ever-widening array of applications. Panels and displays are also becoming larger and with these larger panels are power, brightness and management issues. There are two main configuration options being employed, each with its own pros and cons.

When the LED’s are placed directly behind the panel, they are in direct configuration. The other option used widely is edge configuration where the LED backlighting is provided by LED’s installed around the perimeter of the panel. Either design option will give you the capability of color variations, consistent movement and the bonus of virtually eliminating outages.

The direct configuration utilizes LEDs arranged in a matrix behind the panel to directly illuminate the display. This configuration uses less current through many small strings of LEDs, which allows for local dimming of individual arrays in addition to improved coloration and contrast. Drawbacks of this configuration are that you need to use a high-speed data bus and your programming will be much more complex. This configuration also requires thicker panels to allow space for the light emanating from the LED’s to diffuse.

Edge configuration illuminates the display from the panel edges using fewer strings with more LEDs.  This requires a higher voltage power supply to drive the LEDs, however, there is a less complex control system required and fewer LED current sink drivers. Being arranged in longer strings around the perimeter also allows for a much thinner display. Newer systems use a phase delay evenly across the strings to aid in reducing the peak inductor current inherent to the use of a higher voltage power supply. This configuration is becoming the standard when retrofitting large screen LCD displays.

Whether you are looking for small or large panel displays the boundaries between LED lighting and displays are blurring into one world where the highest quality and quantity of content is provided by one device type. The experts at VCC are prepared to help you plan for the requirements of your display type, placement, thermal management and power. Our line of VCC Lite proprietary products use UL rated (94-V0) material to assist in heat dissipation for all large panel applications and includes an extensive selection of LEDs, panel mounts, clips and interconnects to help you achieve your panel design visions. Click here and contact VCC today for more information.

The many benefits of LEDs have now led to a wide spread rush to implement them in a variety of new ways. One of the fields in which LEDs are taking over is backlighting for various applications from televisions, to IPOD displays and numerous LCD devices.

Regardless of the particular application, Engineers are in agreement regarding several ways in which LED devices provide advantages over other backlighting options such as CRT and fluorescent bulbs. The benefits of LED usage in backlight applications include:

• Improved Reliability – As they are solid-state devices, LEDs have a longer lifespan typically lasting over 100,000 hours. A benefit of solid state devices, LEDs will perform consistently from installation to end of life cycle as opposed to florescent options which continuously lose up to 50% of their light output over their life cycle.
• Lower Power Consumption – LED backlights have lower power consumption than traditional backlighting sources. Manufacturers quote a 60% reduction in power consumption for LED backlighting compared to conventional mercury-arc lamps.
• Blur Reduction and Brightness – LCD displays have a motion blur effect primarily because an LCD pixel remains lit, unlike the CRT phosphor screens which are strobed for a very short time. To resolve this issue, one of the latest improvements being employed by large manufacturers is to use LED for the backlighting. They then employ a new scanning technology that strobes the horizontal rows of LEDs from top to bottom. This approach is also superior in reducing computer generated motion blur produced by video games.
• Blacker blacks – The improved dynamic contrast ratio achieved through use of LEDs for backlighting creates improved contrasts, stronger blacks and whites as well as a greater range of color levels in between. This is accomplished by utilizing multiple LEDs to vary the backlighting across the LCD screen based on the image displayed.
• Wider Color Array – LED’s cover a broader range of red and greens well over the NTSC standards. This results in a more extensive range of colors allowing images to appear more life-like. Current improvements using LED backlighting are bringing the available color array closer to the human eye’s perception range.
• Environmentally friendly – The significantly lower power requirements of LEDs result in reduced air pollution from carbon emissions. The longer life span of saves maintenance costs by being replaced less often. In addition, LEDs do not contain mercury and thus are not only easier and less expensive to dispose of they are safer and leave less of an environmental impact. Even Apple computer began changing to LED backlit display in their efforts to become a “greener apple.”

Though using LEDs in backlighting applications is still more expensive at this time, the benefits are overcoming the cost concerns. The new development in LED materials will also reduce the price in the future. Regardless, the benefits are so strong that the result has been an increased demand for LED use in backlit applications in all sizes. This will significantly boost LED production requirements immediately and into the future. VCC Optoelectronics is happy to provide you with LEDs and LED mounting components for your entire project.  Check out our catalog for LEDs as well as products you will require to complete a successful and innovative PCB design.