CITIZEN WATCH CO., LTD.
2,028Patents
520Active
2,028Granted
51Portfolio score
Filing activity: Nov 30, 1973 → Feb 5, 2024 · 42 expiring within 5 years
Most-cited patents
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US4451743A | DC-to-DC Voltage converter | Electricity | 1,516 | Expired |
| US4345249A | Liquid crystal display panel | Physics | 187 | Expired |
| US5224059A | Device for measuring altitude and barometric pressure | Physics | 170 | Expired |
| US4119368A | Elastomer display device | Physics | 169 | Expired |
| US5815233A | Optical device containing a liquid crystal element for changing optical characteristics of a lens element | Physics | 163 | Expired |
| US6646697B1 | Liquid crystal display | Physics | 151 | Expired |
| US6069711A | Portable printer/facsimile device | Electricity | 147 | Expired |
| US6338980B1 | Method for manufacturing chip-scale package and manufacturing IC chip | Electricity | 145 | Expired |
| US4783772A | Wristwatch with pressure sensor | Physics | 141 | Expired |
| US5739588A | Semiconductor device | Electricity | 140 | Expired |
| US6690438B2 | Liquid crystal display panel | Physics | 140 | Expired |
| US6271901A | Liquid crystal display device with two reflective polarizers providing metallic appearance effects | Physics | 140 | Expired |
| US4345248A | Liquid crystal display device with write-in capability | Physics | 138 | Expired |
| US6567060B1 | Liquid display | Physics | 137 | Expired |
| US6301100A | Portable electronic device having a connector and a cable for connecting with an external device | Electricity | 133 | Expired |
| US6580479B1 | Timepiece | Physics | 129 | Expired |
| US4170104A | Switch mechanism for wristwatch | Emerging Cross-Sectional Technologies | 129 | Expired |
| US6525707B1 | Liquid crystal display device and its driving method | Physics | 126 | Expired |
| US6414910B1 | Timepiece | Physics | 125 | Expired |
| US6118219A | AC driver having three power supply voltages including an internally generated voltage | Emerging Cross-Sectional Technologies | 122 | Expired |
| US6191881A | Variable focal length lens panel and fabricating the same | Physics | 120 | Expired |
| USD269254S | Wrist watch | General | 120 | Expired |
| US4642619A | Non-light-emitting liquid crystal color display device | Physics | 118 | Expired |
| US5467913A | Solder ball supply device | Electricity | 113 | Expired |
| US4430648A | Combination matrix array display and memory system | Physics | 113 | Expired |
Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.