Inventor
Masaaki Sofue
Inventor
Tokyo, JP
Overview
Patents· 13 as inventor
Public. Assignee & technology derived from the patent record. Each patent links to its LexDana page.
G11Bprimary
G11BInformation storage based on relative movement between record carrier and transducer43%
H01LSemiconductor devices13%
H10HInorganic light-emitting semiconductor devices having potential barriers13%
C09KMaterials for miscellaneous applications, not provided for elsewhere9%
G02BOptical elements, systems or apparatus9%
H05BElectric heating9%
H10WGeneric packages, interconnections, connectors or other constructional details of devices covered by class h104%
PatentTitleYear
9,548,426'Semiconductor light-emitting device'20179,190,583'White light emitting device and display apparatus'20158,928,220'White light emitting device and display apparatus'20156,353,583'Signal operational circuit for a multi-beam pick-up device'20026,147,947'Optical disk apparatus for accessing optical disks with different substrate thicknesses'20006,128,259'Optical pickup apparatus for accurate detection of a tracking error signal'20005,991,251'Method and apparatus for changing laser beam power of an optical storage device for various types of compact disks'19995,926,451'Optical disk unit having reduced wobble'19995,875,155'Optical disk unit having reduced recording and reproducing errors'19995,737,292'Optical data recording/reproducing device'19985,668,793'Disk cartridge driving apparatus'19975,392,274'Optical pickup device'19955,086,422'Optical disk apparatus'1992Career & activity timeline
Assembled from patent assignee/location history and declaration credentials.
1992–2002Patents assigned to RICOH KK (10)· patent assignee history
1992–1998Based in Hadano, JP· patent location history
1999–2002Based in Tokyo, JP· patent location history
1999Based in Machida, JP· patent location history
2000Based in Yokohama, JP· patent location history
2015–2017Patents assigned to SAMSUNG ELECTRONICS CO LTD (3)· patent assignee history
2015–2017Based in Seongnam-si, KR· patent location history
Inventor activity
Assignee and location history derived from the patent record.
Assignees
| Assignee | Patents | Span |
|---|---|---|
| RICOH KK | 10 | 1992–2002 |
| SAMSUNG ELECTRONICS CO LTD | 3 | 2015–2017 |
Locations
| Location | Patents | Span |
|---|---|---|
| Tokyo, JP | 4 | 1999–2002 |
| Hadano, JP | 4 | 1992–1998 |
| Seongnam-si, KR | 3 | 2015–2017 |
| Yokohama, JP | 1 | 2000 |
| Machida, JP | 1 | 1999 |