Design LED's products are typically ~1mm thick and mechanically flexible, with a bend of 5mm over 40mm distance. According to the particular product specification, LEDs are embedded within the light-guide material using a proprietary process. Therefore the LEDs can be placed anywhere across the panel and not just at the edges.
Flexible panel The resulting product performance is similar to standard injection-molded, acrylic backlights, typically providing 500 cd/m2 luminance from a single medium-brightness LED over a 1.5-inch diagonal area. The company has patent-protected the concept and manufacturing process, and operates an outsourced manufacturing business model.
Typically, the products are produced on transparent polyester or polycarbonate substrates. Standard printing processes - UV screen-printing, press or machined cutting, and lamination - are used to make up the patterned structure. There is no injection molding of the light-guide, so it is effectively a tool-less process.
The company uses industry standard side-mounted LEDs, and has developed critical design and process know-how to enable good cost/performance.
Advantages and applications
Design LED’s products can be viewed as an alternative to electroluminescent (EL) film or in-mould decoration/injection molded light-pipes for many applications.
Compared with conventional LED light-pipe products, which use separate injection-molded acrylic light-guides and LEDs on rigid PCBs, Design LED products are thin, mechanically flexible, give patterned lighting, and deliver a fully integrated module, including connector and LEDs. They also have low non -recurring engineering (NRE), very low unit cost, and are manufactured using only printing process.
Keyboard overlay display Compared to EL film products, Design LED says that its low-voltage products have long life, no electrical noise, wider color range, color-change capability, and lower unit cost.
Gourlay says that Design LED is targeting market sectors outside of the conventional LCD backlighting sector, commencing with high-value products sold into the drinks branding sector.
Other sectors will include promotional (animated graphics), industrial human/machine interface (graphics/switch illumination and indication), automotive (interior lighting and indication for instruments and systems), consumer electronics (product/brand/keypad enhancement), and low-resolution displays (thin/flexible patterned panel).
Research and development programs
The company has a number of on-going R&D programs and is developing bare-die LED processes to enable thin light-guides, down to 100 microns thickness for backlight panels. Down at this thickness, the products are a direct replacement for thin EL in space-constrained applications.
The company is also working on the screen printing of advanced micro-optical structures to give improved light efficiency with low-cost manufacturing methods.