Patent ID: 6785448
Filing Date: 2004-08-31
Classification: G02B

Abstract:
A coupling method of an optical fiber coupler with maximum flat coupling spectrum of a pair of optical fibers, comprising:(1) Combining the pair of optical fibers with different photosensitivity in parallel, and heating and extending specific portions of the optical fibers to form a fused portion and packaged in a substrate; (2) Irradiating the pair of optical fibers by intense ultraviolet light (hereafter referred to as UV radiation) at the same time; (3) adjusting UV radiation and laying the fused portion under focus of the UV radiation for a period of time for making refractive index of the pair of optical fibers markedly different and asymmetric to decrease maximum coupling ratio; and (4) supervising floating state of a peak of light energy loss spectrum of the fused portion by an optical spectrum analyzer, and turning off the UV radiation when the loss spectrum arrives at maximum flat area.