1. Who is Add-Vision?
Add-Vision is the leading developer and licensor of a unique Polymer Organic Light-Emitting Diode (P-OLED) display technology for the low-resolution display and specialty lighting markets. The company’s flexible display technology has caught the attention of the display industry because of its robust display characteristics, and print-based manufacturing process onto thin flexible substrates using low-cost printing equipment and practices. The ability to print P-OLEDs onto flexible substrates makes it a next-generation lighting technology for low-resolution displays and specialty lighting products.
Add-Vision is a mid-stage start-up company that is committed to improving display performance and manufacturability for flexible P-OLED display systems. The company has intellectual property in proprietary ink formulations, flexible substrate handling, printing and processing, optimized driving algorithms, and flexible encapsulation technology.
Since demonstrating the feasibility of fully printed, flexible P-OLEDs in 2002, the company has since established a committed syndicate of private-equity and strategic investors.
2. What are Light-Emitting Polymers (LEP)?
Light-Emitting Polymer (LEP) materials were initially discovered by Jeremy Burroughes, Donal Bradley and Richard Friend at the Cavendish Laboratory in the University of Cambridge in the late 1980’s. Most often based on polyphenylene vinylene (PPV) and polyfluorene (PF) chemistries, these novel plastics are long-chain organic semi-conducting molecules that can transport charge and emit light under DC drive. In terms of processibility, LEP materials are liquid soluble and convertible into ink-like materials. This opens the door to their coating and deposition using a variety of low-cost, high-speed printing methods.
The emission from LEP materials can span the visible and near IR spectrum including Red, Blue, Green, Yellow and White.
The two leading suppliers of raw LEP polymers are Merck OLED and Sumation. Add-Vision is focused not on synthesizing LEP materials, but rather in converting these materials into specially-formulated inks for printed P-OLED. That is, Add-Vision develops proprietary LEP and cathode inks with special additives and formulation recipes to enhance the optical and electrical properties of the LEP materials, while also ensuring these conductive inks can be uniformly deposited into thin films using high-speed printing methods. Every ink is carefully formulated, prepared, printed and processed to achieve a desired set of display characteristics, including high electroluminescence efficiency, operating lifetime performance, color stability, and switching speed.
3. Why the excitement about Polymer Organic Light-Emitting Displays (P-OLEDs)?
LEP materials and the P-OLED displays they enable are viewed by many in the flat panel display industry as a next-generation display technology for high-performance, video-enabled display products such as primary displays used in laptops, mobile handsets and PDAs. Similarly, Add-Vision views its use of LEP materials in its printable P-OLED device structure as a next-generation display and lighting technology for the low-resolution display and backlighting market.
LEP materials offer several key advantages. LEP materials are themselves light-emitting and thus do not require a costly backlight or suffer from LCD filter losses. This aspect alone means they require less power, are thin, light-weight and offer a superior viewing angle. Second, P-OLEDs used in high-resolution RGB displays are now demonstrating impressive display performance including high brightness capabilities (> 10,000 Cd/m2), long operating lifetime (>1,000,000 hours at 100 Cd/m2 for some colors), wide color gamut (RBG), low DC voltage operation, video-enabling switching speeds, and power efficiency on par with inorganic lighting technologies.
Add-Vision’s display technology takes advantage of the same LEP materials used in high-performance RGB displays. However, Add-Vision has developed a modified display structure, proprietary ink formulations and an entirely print-based manufacturing process to be suitable for adoption into lower cost, low-resolution display and backlighting applications. Unlike traditional RGB OLED display technology, Add-Vision’s OLED displays can be completely printed in air onto thin flexible substrates using conventional printing equipment and practices. The result is a flexible display technology that retains the attractive characteristics of P-OLEDs, such as low DC voltage operation, high brightness, wide color selection and flexible substrates, while being simple and low cost to manufacture.
4. How does a doped P-OLED display work?
Add-Vision’s most simple P-OLED device structure consists of a Light-Emitting Polymer (LEP) and air-stable cathode layer stacked onto an ITO-coated substrate, such as PET or PET. The conductive transparent ITO layer, or anode, can be patterned using a simple print-etch process. Then, using a LEP ink containing Add-Vision proprietary additives, an LEP film is printed directly onto the ITO layer. After the LEP layer is dried, an air-stable conductive paste, such as Silver, is then printed onto the LEP layer to form the cathode. Add-Vision has developed a specially-designed conductive paste suitable for printed OLEDs. The entire display undergoes a final annealing process before encapsulation.
When applying a small voltage across the electrodes, injection and transport-enhancing interfacial layer formation occurs in situ the LEP, leading to efficient light emission from the LEP layer without relying on a low work-function electron source. It is this key characteristic of the Add-Vision device that allows substitution of an air-stable cathode in place of an unstable metal electrode commonly used by the RGB high-resolution display industry. As a voltage is applied across the electrodes, electrons from the cathode and ‘holes’ from the anode recombine in the LEP layer creating excitons, releasing energy as light.
5. What are the benefits of Add-Vision’s flexible P-OLED display technology?
As compared to resident technologies in the low-resolution display market, Add-Vision’s P-OLED displays offer persuasive benefits. These benefits include: brilliant color and high brightness potential (>> 100 Cd/m2); low DC voltage operation (< 10V); high system power efficiency; long operating lifetimes (> 1000 hours); wide color gamut (RGB, Yellow, White); thin and flexible form factor; no noise or EMI, and the ability to precisely place light-emission exactly where it is needed.
The cost competitiveness of Add-Vision’s P-OLEDs arises from a number of factors. Primarily, Add-Vision’s displays are manufactured using high-speed, low-cost printing methods over large-area flexible substrates. No multi-million dollar cluster and vacuum-deposition tools are required. Second, Add-Vision’s P-OLEDs are driven by low DC operating voltage requiring no costly inverters and costly driver electronics common in other display technologies. Because P-OLEDs generate no noise or EMI, peripheral shielding components in the packaging are eliminated. Finally, LEP materials are offered in a wide range of colors and are surface-emitting devices, not single point source emitters, like discrete LEDs. This reduces the need for color filters and light diffusion films required by many other display and lighting technologies.
Therefore, Add-Vision’s P-OLEDs offer a compelling set of display benefits with the potential for substantially reduced total system display cost.
6. What are the possible applications for Add-Vision’s P-OLEDs?
Add-Vision will provide product designers the ability to bring special lighting-effects and dynamic information display from places that might not otherwise be possible using today’s incumbent technologies.
Add-Vision’s P-OLEDs are anticipated to impact a broad range of products, including wearable displays; intelligent packaging and smart labels; toys and games; smart cards; point-of-purchase (POP) displays; POS signage; large-format electronic signage; backlights for keypads and input devices; character and segmented displays; and specialty lighting products, to name a few.
7. Can P-OLED displays be purchased from Add-Vision?
Add-Vision’s aim is to develop its flexible P-OLED technology to a point that it becomes a mature, commercially-accepted technology throughout the low-resolution display market, and is now accelerating its transfer into high-volume manufacturing. For special customer projects and small order quantities, Add-Vision can design and fabricate display products at its 10,000ft2 R&D facility in Scotts Valley, California (U.S.).
AVI scales up successful commercialization through collaborations, Joint Development Projects, and Licensing arrangements with manufacturing partners. Because Add-Vision’s P-OLEDs can be easily adopted by a large pool of printing companies and display manufacturers, we can rely on the design, manufacturing and distribution strengths of our partners. For this reason, Add-Vision seeks to pair product companies with our qualified display manufacturer(s) to accelerate development and commercialization.
8. What up front capital investment is required for Add-Vision’s P-OLED display manufacture?
Add-Vision’s P-OLED displays can be fabricated using a manufacturing line that is identical in nearly every respect to the equipment and methods employed in manufacture of flex circuits, thick-film EL displays, membrane switch assemblies with the addition of a flexible encapsulation tool. A single manufacturing line would require cutting tables, printing equipment, several belt ovens, die presses, and an automated testing station. Add-Vision is working collaboratively with a JDA partner to develop a high-speed, lamination-based encapsulation process and tool. A completely furbished facility including encapsulation tooling would cost ~$1 million. The manufacturing line capacity is estimated at 28,000ft2 of displays per month, having a shipment value of $18 million to $22 million per annum.
Many high-end printing and electronic component manufacturers already own and operate a significant portion of the equipment required for Add-Vision’s P-OLED display manufacturing. This greatly reduces the upfront capital investment requirement for these companies.
By comparison, if one were to build a modern OLED facility for fabricating passive matrix display products using RGB high-resolution OLED approaches, the upfront capital investment requirement would easily exceed several hundred million dollars.
9. What is the approximate cost to manufacture Add-Vision’s flexible P-OLEDs?
The cost of printing Add-Vision’s P-OLED lamps is comparable to the cost of printing thick-film EL lamps, less than $0.25 per square inch. The cost range depends in large part on the proportion or percentage of total display area that is light emissive. However, since P-OLEDs are light-emissive surface emitters (not point emitters) and operate under low DC voltage, they eliminate the need for additional backlights, color filters, inverters, AC driver electronics, and shielding against noise and EMI found with other display technologies.
10. What colors can Add-Vision’s display emit? How is this achieved?
There are three primary methods to achieving different color emission.
The first approach is to use LEP materials of different colors which are synthesized by material suppliers to emit a specific emission spectrum or wavelength. The most advanced colors are Red, Green, Blue, White and Yellow. Because LEP materials are light-emissive, they do not require any additional color filters or backlights. Therefore, one can create a multi-color display by printing pixels of different LEP materials onto the same substrate.
A second approach to achieving multi-color displays is by color filters. Color filters are commercially-available, flexible films that can be purchased in a variety of colors, surface finishes and transparencies and mounted onto the front of the P-OLED display to improve visibility as well as offer greater protection of the display from the environment. Sometimes a color filter overlay is used to simplify the manufacturing process and prevent having to print a wide variety of specially formulated inks. White LEP emitters are highly prized because of their characteristically broad emission spectrum that allows a wide variety of color effects to be realized through color filters.
Color selection can also be achieved through a down conversion process. That is, specialty dopants can be added directly into the LEP layer to down-convert the emission of the display to a wavelength of higher wavelength. An example of this approach is used throughout the solid state lighting industry where phosphors and/or dyes down-convert blue to white.
11. What is the thickness of the P-OLED display?
The active area of the display, including the ITO anode, LEP layer and printed cathode, is only 3 microns thick. The total display package, including substrate, active display layers, and final encapsulation create a display thinness of approximately 0.015”. The resulting plastic display is flexible and mechanically robust.
12. Does Add-Vision supply driver electronics to control its P-OLED displays?
Display manufacturers may wish to apply Add-Vision’s display technology to create backlights, light-emissive icons, custom animations, and other scrolling dynamic information. Creating these functionalities requires suitable driver electronics. Add-Vision is developing driving algorithms for its display technology to optimize brightness, operating lifetime, power efficiency and switching speeds. We provide our drive algorithms to our licensees who then incorporate these into their electronic driver design using off-the-shelf electronic components.