A tapered hollow waveguide multiplexer is proposed to combine the output of a multi-wavelength VCSEL array. The
design of the proposed hollow waveguide is presented based on ray optics. We demonstrated the multiplexing of 4-
channel output of a VCSEL array for coupling into a multi-mode fiber with the tapered hollow waveguide. The
wavelength of each channel was allocated with adjusting driving current. The proposed hollow waveguide multiplexer is
useful for realizing compact and low-cost WDM transceivers with a multi-wavelength VCSEL array for high capacity
short reach optical networks.
We have proposed all-optical signal processing using an optically injection-locked two-mode vertical-cavity surface-emitting laser (VCSEL). The operating principle is based on an all-optical inverter using transverse mode switching of an injection-locked VCSEL. The nonlinear transfer function in input-output characteristics enables us to reshape degraded input signal. In addition, the polarization state of the output signal can be tightly controlled by two-mode optical injection scheme. Thus, the polarization state of an inverted signal can be fixed for randomly polarized input light. In addition, 3R regeneration can be achieved with electrically driven clock signal. The proposed scheme gives us novel functions such as all-optical 3R regeneration with optical re-polarization function and NRZ-RZ format conversion. We carried out the modeling based on a multi-transverse-mode rate equation analysis which includes two orthogonal polarization modes, exhibiting a potential of high-speed 4R regeneration and format conversion at 10 Gbps.