Yoshinobu Nekado and Masayuki Iwase
We have developed an optical module using a vertical-cavity surface-emitting laser (VCSEL) chip based on a new material-- GaInNAsSb and having a lasing wavelength in the 1300-nm band. This module has a structure that takes full advantage of the potential of this VCSEL chip, while eliminating components such as the lens, isolator, etc. Use of a passive alignment assembly structure using the original surface mounting (assembly) and high-precision molded plastic package makes for easier assembly, achieving this low-cost, ultra-compact (mini-TOSA size) module. The characteristics obtained include coupling efficiency to single-mode fiber of above 60 % lensless, optical output power of -5 dBm or better, and 2.5 Gbps 20-km isolatorless signal transmission has been confirmed. This module will in future be applicable in compact transceivers (SFF, SFP, XFP and other standards), for which market growth is anticipated.