Takayuki Shimazu

Injection Molded Optical Lens Using a Heat Resistant Thermoplastic Resin with Electron Beam Cross-Linking

The poor heat resistant properties of a transparent thermoplastic resin was improved by electron beam irradiation cross-linking. A correcting aspheric lens for a 635-nm laser diode was fabricated using an injection molding machine, and was irradiated with an electron beam. The near field pattern (NFP), the far field pattern (FFP) at the focus position and the transmittance of the lens did not change after exposure to a 260 °C reflow process for 60 s.

Fatigue Characteristics of the Si Moveable Comb Inserted into MEMS Optical Devices

This paper focuses on the fatigue characteristics of the single crystal silicon (SC-Si) cantilever in relation with the critical design of micro electro-mechanical systems (MEMS). Development of MEMS actuators for optical communication usage is carried out successfully, for example, in optical switches and variable optical attenuators (VOA). In those devices, fatigue characteristics of the MEMS structure are crucial to its practical application. However, fatigue tests using real structures have not been carried out well. In this research, the fatigue life has been inspected at the actual device, under actual usage conditions for the first time. We obtained fracture rate λ from experimental results, and the value of Failure in Time (FIT) A was about 0.3 FIT. This result indicates that these MEMS devices having enough reliability for practical usage.

Reflowable thermoplastic optical lens module for 10-Gbit/s transmission with 850-nm VCSEL

We successfully developed reflowable thermoplastic optical lens module by electron beam cross-linking and fabricated MM-based 10-Gbit/s optical transmitter unit. Experimental result shows good durability for reflow process up to 260 °C.