Printable Field Emitters Ltd. (PFE; Didcot, England) has received investment of 1.5 million pounds ($2.2 million) from Quester Capital Management Ltd., a venture capital company headquartered in London. The new funding will be used to scale up PFE’s facilities to build full-color flat-panel displays up to 15-inch diagonal in size. Production of monochrome 32 x 32-pixel displays has already been demonstrated by the company.
PFE is a development phase company, founded in 1995. In 1996 the company received its first SMART award from the UK government to perform feasibility studies on its patented new flat-panel technology. In June 1998 venture capital provider 3i invested 2 million pounds in the company, allowing PFE to move into the exploitation phase. Further investment has come from 3i, in April last year, and from additional government awards. PFE now operates from a 5000-sq-ft facility, which it leases from the Rutherford Appleton Laboratory in Didcot, and employs around 25 experienced engineers and scientists. The company also has offices in Hartlepool.
The ultimate target of the field emission displays (FEDs) pioneered by PFE is consumer-priced "Hang On The Wall" TV and information displays. In the patented technology used by PFE, each pixel contains an array of hundreds of triode emitter cells. Each cell is approximately 10 microns in diameter, and the gate insulator is 4 microns thick. The emission current is controlled by applying a 20-V swing on the gate and cathode tracks. Low voltage control like this allows low cost CMOS-based drive electronics to be used in the systems. The cathode array is used in conjunction with a high voltage (3 to 5 kV) anode, which is coated with standard CRT phosphors, giving CRT viewing characteristics. Other benefits of this technology are the size of screen that can be produced, up to 42 in. diagonal, and the low cost production of the cathode structure, which is manufactured without any vacuum deposition steps.
PFE aims to have 6-inch monochrome and color demonstrator displays by summer 2001, and to produce a 15-in. piece of a 40-in. color display before the middle of 2002.