Audio indicating system
US4014016A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 29, 1974 |
| Grant date | Mar 22, 1977 |
| Priority date | — |
| Expiry date | Nov 29, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09F2025/005
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A sightless indicating system and method is disclosed that is useful as an indicating device for diverse equipment, including equipment such as an electronic calculator, and is particularly useful by a blind person. When utilized as a part of an electronic calculator, a standard calculator keyboard is modified to include a sign key and an output key so that an operator can initiate output indications and determine the sign of such indications in addition to initiating the customary numerical and function inputs. The customary numerical and function inputs are processed in conventional manner except that the calculator output is converted to a sightless indicating form, such as audible signals indicative of output. For an audible indication of the modified calculator, the output key is depressed and the value of each digit to be indicated is converted to a series of equally spaced output tones at substantially the same frequency with a different number of tones being utilized for each digit to differentiate therebetween. In addition, a steady, low-level output tone is utilized to indicate a decimal point in the audible output of a calculator, while an output tone of the same frequen…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.