Polarization rotator and optical signal processing method

An optical signal processing method, applied to a polarization rotator, the polarization rotator having a first transceiving waveguide, a polarization rotation region waveguide, a mode conversion region waveguide, and a second transceiving waveguide, and

• the first transceiving waveguide having a first end and a second end;
• the polarization rotation region waveguide having a first waveguide and a second waveguide, wherein the first waveguide is located above the second waveguide, the first waveguide is connected to the second end of the first transceiving waveguide, the first waveguide is a non-linear profile waveguide, and the second waveguide is a non-linear profile waveguide;
• the mode conversion region waveguide having a third waveguide and a fourth waveguide, wherein the third waveguide is connected to the second waveguide, the fourth waveguide is on a same horizontal plane as the third waveguide and the second waveguide, the third waveguide is a non-linear profile waveguide, and the fourth waveguide is a non-linear profile waveguide, wherein the first transceiving waveguide does not overlap the second waveguide;
• and the second transceiving waveguide having a third end and a fourth end, wherein the third end of the second transceiving waveguide is connected to the fourth waveguide, and a distance between the fourth end and the second end of the first transceiving waveguide is greater than a distance between the third end and the second end of the first transceiving waveguide;
• and
• the method comprises:
• receiving, by the first transceiving waveguide, an L-order mode transverse magnetic wave (TM) mode optical signal;
• converting, by the polarization rotation region waveguide, the L-order mode TM mode optical signal into an N-order mode transverse electric wave (TE) mode optical signal;
• converting, by the mode conversion region waveguide, the N-order mode TE mode optical signal into an M-order mode TE mode optical signal;
• and
• outputting, by the second transceiving waveguide, the converted-to M-order mode TE mode optical signal, wherein
• N is not equal to M.

An optical signal processing method, applied to a polarization rotator, the polarization rotator having a first transceiving waveguide, a polarization rotation region waveguide, a mode conversion region waveguide, and a second transceiving waveguide, and

• the first transceiving waveguide having a first end and a second end;
• the polarization rotation region waveguide having a first waveguide and a second waveguide, wherein the first waveguide is located above the second waveguide, the first waveguide is connected to the second end of the first transceiving waveguide, the first waveguide is a non-linear profile waveguide, and the second waveguide is a non-linear profile waveguide;
• the mode conversion region waveguide having a third waveguide and a fourth waveguide, wherein the third waveguide is connected to the second waveguide, the fourth waveguide is on a same horizontal plane as the third waveguide and the second waveguide, the third waveguide is a non-linear profile waveguide, and the fourth waveguide is a non-linear profile waveguide, wherein the first transceiving waveguide does not overlap the second waveguide;
• and the second transceiving waveguide having a third end and a fourth end, wherein the third end of the second transceiving waveguide is connected to the fourth waveguide, and a distance between the fourth end and the second end of the first transceiving waveguide is greater than a distance between the third end and the second end of the first transceiving waveguide;
• and
• the method comprises:
• receiving, by the second transceiving waveguide, an M-order mode transverse electric wave (TE) mode optical signal;
• converting, by the mode conversion region waveguide, the M-order mode TE mode optical signal into an N-order mode TE mode optical signal;
• converting, by the polarization rotation region waveguide, the N-order mode TE mode optical signal into an L-order mode transverse magnetic wave (TM) mode optical signal;
• and
• outputting, by the first transceiving waveguide, the converted-to L-order mode TM mode optical signal, wherein
• N is not equal to M.