Average Co-Inventor Count = 4.00
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. Seiko Epson Corporation (2 from 33,404 patents)
2. World Munsell Co., Ltd. (1 from 1 patent)
2 patents:
1. 6135595 - Eyeglass lenses for correcting color vision
2. 5015086 - Electronic sunglasses