Location History:
- Kanagawa, JP (1991)
- Kamakura, JP (1994 - 1996)
- Tokyo, JP (2003 - 2005)
Company Filing History:
7 out of 21,351 
1 out of 832,891 Years Active: 1991-2005
Title: The Innovations of Eiichi Nakagawa
Introduction
Eiichi Nakagawa is a prominent inventor based in Tokyo, Japan. He has made significant contributions to the field of optical technology, holding a total of 8 patents. His work has paved the way for advancements in optical switching and variable attenuation.
Latest Patents
One of Nakagawa's latest patents is a circuit for switching optical paths. This invention features a system of optical switches that activate based on the failure of specific input/output ports. In the event of a failure on the part of a third input/output port, only the first and second optical switches turn ON. Similarly, if there is a failure on the second port, the third and fourth switches activate, and for a failure on the first port, the fifth and sixth switches are engaged. Another notable patent is the optical variable attenuator, which includes polarizers for extracting a predetermined polarized wave component from an input optical signal. This device utilizes an array of Faraday rotators made from ferromagnetic material, arranged in series to rotate the plane of polarization of the input signal. The electromagnetic coils supply magnetic fields to the Faraday rotators, while current supply control circuits adjust the polarization-rotating angle, allowing for fine-tuning even when magnetic fields are not continuously supplied.
Career Highlights
Throughout his career, Nakagawa has worked with Mitsubishi Electric Corporation, where he has contributed to various innovative projects. His expertise in optical technologies has been instrumental in developing advanced systems that enhance communication and data transmission.
Collaborations
Nakagawa has collaborated with notable individuals in the field, including Satoshi Kumayasu and Tadayoshi Kitayama. These partnerships have fostered a creative environment that has led to groundbreaking inventions.
Conclusion
Eiichi Nakagawa's contributions to optical technology through his patents and collaborations highlight his role as a leading inventor in the industry. His innovative solutions continue to influence advancements in optical systems.