Calculator apparatus with electronically alterable key symbols
Patent 4078257 Issued on March 7, 1978. Estimated Expiration Date: 
March 7, 1995. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
March 7, 1995. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3394368 3670322 3760360 3772685 3777222 3855641 3911424 Alphanumeric display means for computer-linked typewriter consoles using a matrix array of liquid-crystal devices Alphanumeric display means for computer-linked typewriter consoles using a matrix array of light-emitting diodes (led's) Programmable keyboard arrangements InventorApplicationNo. 05/716867 filed on 08/23/1976US Classes:708/145, Plural function key200/5R, Multiple switch200/517, Including additional actuator235/145R, KEYBOARDS340/407.2, With input means (e.g., keyboard)341/23, Variable key legends345/173, Touch panel345/176, Transparent substrate having light entrapment capability (i.e., waveguides)349/1, LIQUID CRYSTAL SYSTEM349/83With each cell displaying a different patternExaminersPrimary: Nusbaum, Mark E.Attorney, Agent or FirmAbstractA calculator system having a transparent keyboard includes an apparatus for electronically labeling the keyboard by displaying alphanumeric symbols through the keyboard. The apparatus comprises a keyboard selection device and a liquid crystal keyboard display device having a predetermined number of display planes each containing preselected symbols. The keyboard selection device operates both as a selection device and as an annunciator-feedback device, for selecting the symbols or legends of a given plane to label or configure the keyboard, and for feeding back to a user of the system the status of the selection device when it is activated. An alternative embodiment of the invention utilizes light-emitting diodes (LED's) for labeling the keyboard. | |
