Average Co-Inventor Count = 5.83
ph-index = 3
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. (4 from 42,496 patents)
4 patents:
1. 6590849 - Disk drive apparatus
2. 6496464 - Disk drive apparatus
3. 6477133 - Disk drive with unbalance correcting mechanism
4. 6459668 - Disk type reproducing apparatus and revolution control method