Polymeric beam-steering 1xN fiber-optic switch
In Phase I of this research, we first designed, fabricated and demonstrated a thin-film polymeric thermo-optic waveguide beam deflector based on prism-array heating electrode, whose shape contour was designed to effectively steer the beam at maximal deflection. At 1310 nm, a beam deflection angle of 2.52° with eight corresponding resolvable spots at an applied voltage of eight volts was demonstrated, suggesting a 1×8 switch is possible with this design. An electrode design was proposed to improve the heating efficiency and apply in the design of the 1×N thermo-optic switch in Phase II of this research. Based on the results that demonstrated the beam-steering capability of the prism-array heating electrode, a 1×N thermo-optic switch was designed based on incorporating the prism-array electrode and an elliptic total internal reflection waveguide mirror. At 1310 nm, a 1×6 switching result was demonstrated; the extinction ratios and crosstalks were found to be > 20 dB and < -44 dB respectively. A switching time as low as 4 ms was observed. The device offers a unique advantage for 1×N (N > 2) switching using only one single driving electrode that simplifies the driving scheme. We also proposed a 1×N switch device structure applying the same operational principle except using an extra-small single-prism electrode to replace the prism-array electrode, with which the power consumption is expected to decrease drastically. With the same design and material parameters in the 1×6 switching device, a 1×3 switching can be expected with the power consumption reduced by a factor of 1000 simply due to the extra-small heating area. A 2×2 switch can also be achieved with this extra-small electrode design.