Summagraphics Corporation
69Patents
0Active
69Granted
38Portfolio score
Filing activity: Jul 12, 1974 → Jul 26, 1995
Most-cited patents
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| USD284084S | Digitizer | General | 523 | Expired |
| US5065145A | Method and apparatus for producing signals corresponding to the position of a cursor | Physics | 91 | Expired |
| US5369227A | Stylus switch status determination in a digitizer tablet having a cordless stylus | Physics | 67 | Expired |
| US4999462A | Position determining and digitizing method and device | Physics | 56 | Expired |
| US4786764A | Digitizer stylus with pressure transducer | Physics | 51 | Expired |
| US5581052A | Pressure sensitive stylus having resiliently compressible tip element | Physics | 44 | Expired |
| US4794388A | Method of and apparatus for controlling a display | Physics | 40 | Expired |
| US4081603A | Position coordinate determination device | Physics | 40 | Expired |
| US4018989A | Position coordinate determination device | Physics | 34 | Expired |
| US4482784A | Position determination device | Physics | 33 | Expired |
| US4992630A | Digitizer tablet with user customization of stylus proximity and pressure | Physics | 33 | Expired |
| US4857903A | Electro-optical mouse with improved resolution for compensation of optical distortion | Physics | 32 | Expired |
| US5004872A | Digitizer tablet with pressure stylus | Physics | 30 | Expired |
| US4936683A | Optical tablet construction | Physics | 30 | Expired |
| USD327476S | Digitizing stylus | General | 29 | Expired |
| US4952757A | Low-power electromagnetic digitizer tablet | Physics | 29 | Expired |
| US4831566A | Method and apparatus for calibration of a charge ratio digitizer | Physics | 29 | Expired |
| US4568182A | Optical system for determining the position of a cursor | Physics | 26 | Expired |
| US5004871A | Digitizer stylus having side switch | Physics | 26 | Expired |
| US5111005A | Graphics tablet with N-dimensional capability | Physics | 26 | Expired |
| US5383733A | Ribbon cassette for a printer | Performing Operations; Transporting | 25 | Expired |
| US5214448A | Belt-drive tensioning system which uses a pivoting member | Physics | 25 | Expired |
| US5153386A | Digitizer tablet with illuminable working surface | Physics | 24 | Expired |
| USRE34095E | Digitizer stylus with pressure transducer | General | 24 | Expired |
| US5066833A | Low power sensing apparatus for digitizer tablets | Physics | 23 | Expired |
Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.