Average Co-Inventor Count = 4.03
ph-index = 4
The patent ph-index is calculated by counting the number of publications for which an author has been cited by other authors at least that same number of times.
Company Filing History:
1. Hitachi, Ltd. (7 from 42,508 patents)
2. Hitachi Video Engineering, Incorporated (1 from 67 patents)
7 patents:
1. 4992891 - Dual record/read head video recording and playback apparatus with
2. 4901297 - Optical magnetic recording and reproducing method and apparatus capable
3. 4556917 - Magnetic recording/reproducing apparatus for video and sound
4. 4524380 - Chroma signal recording and reproducing circuit
5. 4497000 - Magnetic recording/reproducing apparatus
6. 4497004 - Picture reproducing apparatus in a helical scanning video tape recorder
7. 4466026 - Record/reproduce circuit for VTR