Norihiko Sekine

Title: Norihiko Sekine: Innovator in Semiconductor Laser Technology

Introduction

Norihiko Sekine is a prominent inventor based in Kawasaki, Japan. He has made significant contributions to the field of semiconductor laser technology, holding a total of 5 patents. His work focuses on developing advanced laser systems that enhance communication technologies.

Latest Patents

One of Sekine's latest patents is the Tunable Wavelength Laser. This invention features a light oscillation part that includes an active layer for generating light through current injection. It also incorporates a tuning layer with an intermediate layer that allows for varying the oscillation wavelength by current injection. Additionally, a diffraction grating is formed near the active layer and tuning layer, along with a light amplification part that amplifies light through current injection. This integration on a semiconductor substrate enables wide wavelength variation ranges and significantly increases output light.

Another notable patent is the Distributed Feedback Semiconductor Laser. In this design, a tuning layer is spaced apart from the active layer in the thickness direction, with the tuning layer having a transition wavelength shorter than the wavelength of light emitted from the active layer. A diffraction grating layer is positioned between the active and tuning layers, with its refractive index periodically changed along the optical resonator direction. This configuration allows for independent current supply to both the active and tuning layers, resulting in a TTG-DFB laser that maintains a proper coupling coefficient and is suitable for communication light sources.

Career Highlights

Norihiko Sekine is currently employed at Fujitsu Corporation, where he continues to innovate in the field of semiconductor technology. His work has been instrumental in advancing laser systems that are critical for modern communication applications.

Collaborations

Sekine has collaborated with notable colleagues, including Akinori Hayakawa and Yoshihiro Sato. Their combined expertise has contributed to the development of cutting-edge technologies in the semiconductor laser domain.

Conclusion

Norihiko Sekine's contributions to semiconductor laser technology have positioned him as a key figure in the field. His innovative patents and collaborations reflect his commitment to advancing communication technologies.