The shift key modifies the meaning of keyboard keys. Where this is other than upper casing, both meanings are printed on the keycap. This project used rear projection to extend the shift concept to the huge Kanji alphabet.
See Tektronix for more system prototypes.
I reused numerous components I had built for other projects and found a few new ones too.
I simulated the menu logic using character graphics from my aborted Character Graphic NSD Editor.
I imported Kanji character files using regular expressions and printf for Data Wrangling Font Files
I organized my program as multiple asynchronous tasks deployed on the multi-microprocessor architecture of the Generic Digital Instrument.
I wrote in Tesla using tools and techniques I developed for Multi-Processor Debugging.
I used CDC 6000 APL to construct, test and download Vector Lookup Tables.
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Apple recently patented a mechanism for achieving the same effect with OLED displays in each keycap. Patent 10,877,570, December 29, 2020. post