Average Co-Inventor Count = 5.39
ph-index = 2
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-high-technologies Corporation (2 from 2,874 patents)
2. Hitachi Construction Machinery Co., Ltd. (2 from 1,504 patents)
4 patents:
1. 12141723 - Site management system
2. 11475388 - Work management system
3. 10418224 - Plasma etching method
4. 9960014 - Plasma etching method