IDTechEx technology Analyst Dr Harry Zervos and Dr James Caruso, VP of Sales & Marketing for TRED Displays, based in Albuquerque New Mexico, recently discussed the reflective, bi-stable, green-tech EMD2TM display technology based on magnetic self-assembly the company is developing.
This display developed and currently being commercially produced by TRED, consumes less than 5% power compared to LED displays.
The smallest pixel size achievable is approximately 3mm in size so this is a technology that is suitable for robust signage and point-of-purchase markets where larger format displays are required due to the larger viewing distances.
"The integration of digital content in outdoor signage is currently served by LED technologies, with a cost of approximately US$200/sq. ft, a cost that is sometimes prohibitive. LCD or Plasma displays are most often used for indoor applications equally cost prohibitive for many users. TRED displays are competitive as they are closer to the cost of ordinary printing, enabling the addition of digital content with little added cost," says Dr. Caruso.
"LEDS are also heavy and thick requiring significant install cost and are light emitting by nature. A TRED display of 4 numerals (2 superior, 2 inferior at a size of 17''x 9'' is approximately 5 mm thick, weighs less than 2 pounds and 8 AA batteries could provide adequate energy for the display to run for about a year, when changing the image once or twice a day. Because TRED's display products are reflective and not light emitting like LEDs, they fit seamlessly into printed reflective graphics".
The company's first product is a 2-colour display, with the added advantage that these colours could be virtually any two colours, which would make the technology fit to match company logos, corporate colours etc.
How Tred displays work
At the core of TRED's EMD² technology are proprietary magnetic composite fibers called EMFibers™. TRED scientists have developed these new multi-component composite materials that combine optical plastics with high power rare-earth magnetic alloys. After manufacturing, these fibers are magnetized whereby they self-assemble, creating a unique, bi-stable reflective display. TRED pixels are completely bi-stable and require no power to sustain an image. To change a pixel, the fibers are "written" with a short electromagnetic pulse through TRED's proprietary low cost PCB backplane. In as little as 50 milliseconds the EMFibers "flip" to the alternate color state.
Manufacturing
TRED's initial production capacity will be 500 to 2500 units/month through 2009. The EMFibers which make up the displays front plane are manufactured using a triple-extrusion process. It's a reliable manufacturing process with no fundamental physical challenges or problems in terms of scalability. Current displays are rigid and semi-flexible ones may be considered. TRED's backplane (which usually dominates the cost of more traditional displays) is highly proprietary in its design but is produced using traditional low-cost PCB processes. The move towards flexible displays would require a move to flexible PCBs.
Relevance to printed electronics
According to Dr. Caruso, printing technologies fit nicely with TRED displays. Although they are currently not using printing technologies in their "electronics" manufacturing processes, inkjet printing techniques lend themselves to the type of technology and resulting HybridSigns™ that TRED's display products enable. "In the field of printed electronics and displays, inkjet has been used to limited success. This is due in large part to the fact that its resolution and ink/materials requirements for inkjet are not consistent with the vast majority of high-end, capital-intensive electronic and display devices. Where inkjet is strong, is where it naturally found a home: graphics, which include signs, banners, etc. TRED realizes there is a need for a low-cost reflective display for this signage market where HybridSigns can be produced. HybridSigns are signs that consist mainly of fixed image printing and a smaller "digital" portion, namely displays provided by TRED. Inkjet is a method of choice to produce the fixed-image portion of these HybridSigns, allowing it to do what it does best."
For more information on TRED displays, attend Printed Electronics USA 2008 where the company will be presenting more information on their technology, or contact Dr James Caruso directly at jcaruso@treddisplays.com.
Images source: TRED Displays
