| 摘要 |
PURPOSE:To obtain the small-sized wavelength multiplex isolator without polarization dependency by composing the multiplex optical isolator of wavelength multiplexing and demultiplexing parts, mode selection parts, a nonreciprocal mode conversion part, and a reciprocal mode converter. CONSTITUTION:This optical isolator is equipped with the wavelength multiplexing and demultiplexing parts 21 and 21' formed at the light incidence end and light projection end of quartz glass single-mode waveguides 19 and 19', two optical directional couplers 18 - 18''' formed in the quartz glass single- mode waveguides 19 and 19', and mode selection parts 7 and 7' composed of two single-mode waveguides. Further, the isolator is equipped with the nonreciprocal mode converter 8 composed of a single-mode waveguide of magnetic garnet sandwiched between the mode selection parts 7 and 7' and the reciprocal mode converter 9 which has a stress release groove 12 formed in part of a clad layer 10 to specific length along a core part 11. Consequently, the optical isolator which is small in size and inexpensive and operates with plural wavelengths at the same time and has no polarization dependency is obtained. |
