WHEN the British government wasdebating as to whether or not it shouldintroduce identity cards, it had severaloptions before it. The cards could bemade available on a voluntary basis ordriving licences with photos could double as identity cards. The third optionwas to make it compulsory for everyone to carry a government card which carries all personal details. Smartcards could be used to store a widerange of pictorial and textual information. But these could be issued only at arelatively high cost. Certain recentdevelopments seem to have broughtthese cards within the Britishgovernment's reach.
Motorola, the US communicationsgiant has linked up with Matsushita ofJapan and bought the IndalaCorporation, an electronics company inSan Hose, California, to offer a newmemory technology which cuts the costof memory storage. Kodak IBM have alsodeveloped a 'hypercompression' systemthat stores photographs in such a smallmemory space that even a magneticcredit card can carry the owner's electronic picture (Everyday with PracticalElectronics, August, 1995).
Existing memory cards either have abuilt-in battery to data inside volatileRandom Access Memory (RAM) or usehigh current to write to a non-volatilememory - the Electrically EraseableProgrammable Read Only Memory(EEPROM). The new material, YI is a ferroelectric ceramic material similar to ahigh temperature superconductor.When formed into a honeycomb latticeof individual cells, the cells store bits ofdigital code as isolated pits of capacitivecharge. The written charge patternremains permanent until a fresh writingcurrent is applied.
The YI theory was proposed fiveyears ago by researchers at theUniversity of Colorado but Matsushitadeveloped and patented a way of making a cell matrix by a technique similarto that used to fabricate microchipsfrom silicon wafers. The IndalaCorporation then worked out a way ofusing the matrix inside a credit card orresin button, along with a miniatureradio transponder and aerial made from400 turns of very thin wire. The matrixuses the power of an interrogation signal to send back a response signal whichis coded to carry whatever informationis in the memory. Motorola and Indaladesign the YI cell structures whichMatsushita fabricates in Osaka, Japan.
"It is very nearly the perfectmemory material," says Rudyard Istvan,the Motorola president of Indala. "But ifyou do not use exactly the right recipefor the mix, the cake turns out flat."
YI reads and writes almost instantaneously while RAM, Flash and EEPROMtake one second to read each kilobite ofdata. Also, Flash and EEPROM memoriesfail after they have been written anderased a few hundred thousand times. YIsurvives a billion cycles.
Says Istvan: "We have alreadythought of fusing the system to storeelectronically compressed photographs.You could walk through passport control without taking the card out of yourpocket. The only way to counterfeitcards would be to build a silicon waferfabrication plant and modify it for YIprocessing".