Average Co-Inventor Count = 6.44
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. (4 from 42,508 patents)
2. Hitachi Koki Co., Ltd. (2 from 1,267 patents)
3. Hitachi Chemical Company, Ltd. (1 from 1,641 patents)
4 patents:
1. 5215842 - Photosensitive element for electrophotography
2. 4430404 - Electrophotographic photosensitive material having thin amorphous
3. 4405703 - Electrophotographic plate having an age-hardened aluminum substrate and
4. 4253038 - Light source excited by high frequency for Zeeman effect atomic