| 摘要 |
PROBLEM TO BE SOLVED: To obtain an optical fiber which may be easily produced, is good in operability, is usable in many applications and is formed with one or plural rectangular core portions in mid-way by forming the core portion in at least mid-way to a shape of a nearly rectangular cross section. SOLUTION: The wavelength transmitted dependently upon an x-axis direction of a wedge type etalon 3 varies and, therefore, the individual detectors 4a to 4n of a photodetector array 4 are formed according to the different transmitted wavelengths. The fiber end face 2 is rectangular and the photodetector array 4 is arranged with the rectangular strip-like detecting regions 4a to 4n alongside each other to the rectangular shape as a whole. The shape of the core 1a of the fiber 1 is made to nearly comply with the shape of the detecting regions 4a to 4n of the photodetector array 4. Then, both may be efficiently optically coupled. The rectangular core 1a extends to nearly the entire part of the optical fiber 1 in this case. The polarization state is preserved in the core (waveguide) of such rectangular cross section and, therefore, the optical fiber is suitable for use as the polarization maintaining fiber. |
