| 摘要 |
<p>A compact optical circulator which can be expanded into a large number of optical ports is provided. For each port (1, 2, 3, 4), the circulator has an optical port assembly (10, 20, 30, 40) which has an end of an optical fiber (15, 25, 35, 45), a collimator subassembly (11, 21, 31, 41), and a birefringent crystal (12, 22, 32, 42). The collimator subassembly (11) collimates light from the optical fiber end (15) into a beam of collimated light and focusses a beam of collimated light to the optical fiber end (15) in a reverse direction. The birefringent crystal (12) is dimensioned and arranged with respect to the collimator subassembly (11) to split the collimated light beam from the collimator subassembly (11) into two parallel beams of light linearly polarized perpendicularly to each other, and to combine parallel beams of light linearly polarized perpendicularly to each other in the reverse direction into a beam of collimated light toward the collimator subassembly (11). The optical port assemblies (10, 20, 30, 40) are arranged in a linear array and a combination of polarization interfaces and planar relecting surfaces guide the light beams between the optical port assemblies (10, 20, 30, 40) so that the circulator can be designed with as many optical ports as desired.</p> |
