Technological R&D, as everyone knows, takes years. It might seem like decades at times. The printed electronics industry is replete with companies and institutions steeped in research and development and at various stages along the creative path. Some still have miles to go to produce a commercial product. Others, like Kent Displays, is now seeing the fruits of its efforts reach the consuming public.
Early this month at the SID Display Week in San Antonio, TX, USA, Kent Displays featured its Reflex No Power LCDs, which retain an image without power, and offer such optical characteristics as sunlight readability and wide viewing angles. These features, coupled with the product’s flexibility, durability and thin plastic substrates, provide what the company describes as a more versatile, sustainable medium than traditional paper and backlit LCDs. Kent Displays’ technology, which earned it a Flexi Product Development award this year from the FlexTech Alliance, is attracting the attention of quite a few product manufacturers.
“The type of liquid crystal used in our technology is called cholesteric," says Kevin Oswald, communications director for Kent Displays. “Any image put on the display will remain indefinitely without any power being supplied.” These LCDs are also known as ChLCDs.
At the SID show, Kent presented its electronic skins, which are film laminates 65 microns thick with active liquid crystal technology inside. These can be used, for example, as the decorative color shell on a cell phone or other device. Color can be changed on command, and power is utilized only during the color shift process. Once the color is in full display, the electronic skin uses no power whatsoever to maintain the color. Each layer of an electronic skin is additive color and is either reflective or transmissive. The color variations result from switching between the two modes.
“We currently make a skin that can change from one to eight colors,” Oswald notes. “We have a version of it that we silkscreen a pattern onto the back of the bottom layer of the substrate, so that the pattern is combined with the LCD image.”
Beyond the skins, Kent Displays is at work on ChLDC technology for electronic writing tablets, smart cards and e-readers. The company already produces a basic version of its e-writing tablet, which is useful for teaching children to write and draw, for example, Oswald says. But a new portable device is about to launch which comes with a stylus and which recognizes various pressures. “Some displays will recognize only one line thickness,” notes Oswald, “and you can’t shade any area. Our new product has a black background and can produce white lines with pressure. It will have memory and selective erase, and can be used by students and professionals as a notebook.” He estimates that the next-generation product will be introduced in about six months.
As for the e-readers, that’s a topic that always generates interest. The products available today, which includes the Kindle, have a black and white display. “Producers of e-readers want color capability as the next level of technology,” says Oswald. “Our cholesteric color technology has been licensed by Fujitsu for a product known as the Flepia, which has a color screen.”
Kent Displays is an offshoot of the Liquid Crystal Institute at Kent State University in Ohio, a center for basic and applied liquid crystal research and home to the Graduate Chemical Physics Interdisciplinary Program. The company was founded in 1993 and today employs more than 60 people. In October of last year, it installed a new roll-to-roll production line to mass-produce the Reflex LCDs from plastic rolls, a line which it claims is the first of its kind in the world, producing no waste water or chemicals and less solvent emissions than sheet-based processes.
Because of the decision to manufacture using roll-to-roll substrates, Oswald says, the labor component at the Kent plant is much lower than if sheets were used. “We put the crystal layer on the substrate, laminate it with another layer, and cut to finished shapes. For a device with a secondary information display, such as a telephone, we can make a skin to fit the case of the phone so that the information display isn’t covered; you can still see it.
“The applications for this technology, we say, are nearly endless,” adds Oswald. “Every day we get inquiries for potential uses.”
The state of Ohio has taken note of the pioneering work of Kent Displays. In May, the company announced a $4.9 million award from the Ohio Third Frontier Commission’s Research Commercialization Program. The award is being used to develop the electronic skins and other cholesteric LCD products. Kent Displays’ program collaborators include plastic substrate producer DuPont Teijin Films and electronic chip designer Solomon Systech, as well as Kent State University and the University of Akron.
Specifically, the support from Ohio Third Frontier will enable the company to develop numerous Reflex electronic skin advancements, such as performance (optical, environmental, durability), size, conformability (complex shapes) and electronics (conductivity, miniaturization). The funding also will be used to refine and optimize the roll-to-roll production process.
Albert Green, CEO of Kent Displays, credits the state of Ohio with its forward thinking in encouraging new technological development and production: “Kent Displays is extremely excited to receive Ohio Third Frontier funding to develop the next generation of Reflex electronic skins,” Green says. “Ohio Third Frontier is essential to the future of the state of Ohio. It is an important catalyst for the state’s emerging high technology sector and creating and retaining jobs within it. This sector is redefining the state’s economic base beyond traditional manufacturing and services to meet the needs of a rapidly-advancing, technology-based society. Support through Ohio Third Frontier is a key enabler of commercializing products like our Reflex electronic skins that meet these needs. We are confident that with this support Kent Displays and the state have a secure future.”