Abstract: A device for a passive module of optical communication includes a first housing made of material with low coefficient of thermal expansion, and a second housing made of material with negative coefficient of thermal expansion. A longitudinal receiving recess is defined at the first housing for receiving the second housing, thereby effectively and accurately restraining shift of reflective central wavelength of a fiber Bragg grating (FBG) under variation of environment temperature during working. Also, A tunable mechanism including an elastic recess is formed with the first housing and a tunable member which can tune the width of the elastic recess through pressing the first housing, thereby independently switching reflective central wavelength of the FBG at desire.

Abstract: An apparatus and method for compensation of central wavelength shifting of a fiber grating by material with Invar effect. In the present invention, a substrate having a negative thermal expansion coefficient and a fiber with fiber grating is provided, and two portions of the fiber at both sides of the fiber grating are fixed to the substrate. The substrate and the fiber are satisfied with ?eff?bragg=K?AfEf(?c??f) in which ?eff is an effective thermal expansion coefficient of the fiber grating, ?bragg is a Bragg wavelength, K? is a constant, Af is a cross-section area of the fiber, Ef is an elastic modulus of the fiber, ?c is the negative thermal expansion coefficient of the substrate, and ?f is a thermal expansion coefficient of the fiber.

Abstract: A coupling method of a coupler includes the following steps: (1) making a pair of optical fibers with different photosensitivity fused and drawn, (2) irradiating specific portions of the pair of optical fibers by intense ultraviolet light at the same time for making refractive index of the pair of optical fibers markedly different, (3) supervising coupling light energy loss spectrum and gradually adjusting the intense ultraviolet light for decreasing maximum coupling ratio and achieving an optical fiber coupler of optimum flat spectrum, thereby improving fabricating process and reducing deficient products.

Abstract: An automatic device for assembling a fiber collimator. The fiber collimator includes a tubular holder, an optical fiber disposed at an end of the tubular holder, and a GRIN lens disposed at the other end of the tubular holder. The automatic device includes a screen, a laser light-source and a driving table. The laser light source emits a laser light to the GRIN lens to obtain a first elliptic pattern and a second elliptic pattern on the screen, wherein the first elliptic pattern has a first major axis and the second elliptic pattern having a second major axis. The driving table rotates the optical fiber until the first major axis of the first elliptic pattern is parallel to the second major axis of the second elliptic pattern.

Abstract: An automatic device for assembling a fiber collimator. The fiber collimator includes a tubular holder, an optical fiber disposed at an end of the tubular holder, and a GRIN lens disposed at the other end of the tubular holder. The automatic device includes a screen, a laser light source and a driving table. The laser light source emits a laser light to the GRIN lens to obtain a first elliptic pattern and a second elliptic pattern on the screen, wherein the first elliptic pattern has a first major axis and the second elliptic pattern having a second major axis. The driving table rotates the optical fiber until the first major axis of the first elliptic pattern is parallel to the second major axis of the second elliptic pattern.

Abstract: An apparatus and method for compensation of central wavelength shifting of a fiber grating by material with Invar effect. In the present invention, a substrate having a negative thermal expansion coefficient and a fiber with fiber grating is provided, and two portions of the fiber at both sides of the fiber grating are fixed to the substrate.

Abstract: An automatic apparatus for assembling an optical fiber cable, a pre-assembled element and a sleeve. The automatic apparatus includes a glue-injecting mechanism, a feeding mechanism, a forging press, a movable stand, a clamping and rotating mechanism and a robot. Glue is injected into the pre-assembled element by the glue-injecting mechanism. Then, the robot conveys the pre-assembled element from the glue-injecting mechanism to the clamping and rotating mechanism. The optical fiber cable and sleeve are supported by the movable stand. The stand is moved toward the pre-assembled element so that the optical fiber cable enters the pre-assembled element. Then, the optical fiber cable is further pushed into the pre-assembled element by the feeding mechanism. Then, the pre-assembled element is covered with the sleeve by the feeding mechanism. Then, the sleeve is pressed by the forging press so that the sleeve is deformed to engage the pre-assembled element.