摘要:
Disclosed is an apparatus for measuring a residual stress and a photoelastic effect of an optical fiber, which includes: a light source; a rotary type optical diffuser distanced from the light source in a predetermined distance for suppressing the spatial coherence of a light radiated in the light source; an optical condenser for condensing the radiated light passed through the optical diffuser into a spot where the optical fiber is located; a polarizer for polarizing the light passed through the optical condenser into a 45° linear polarized light from an axis of the optical fiber; a polarization analyzer, installed at 90° angle with respect to the polariscope and attached closely with the optical fiber, to prevent the penetration by the background image of the optical fiber; an optical fiber strain unit including a strain sensor for straining the optical fiber on the polarization analyzer toward a longitudinal direction and measuring the strain on the optical fiber; an object lens for magnifying the image of the light penetrated through the optical fiber; and a charge coupled device(CCD) array for measuring the penetration variation of the optical fiber caused from the strain caused by the optical fiber strain unit over the optical fiber.
摘要:
Disclosed is an apparatus for measuring a residual stress and a photoelastic effect of an optical fiber, which includes: a light source; a rotary type optical diffuser distanced from the light source in a predetermined distance for suppressing the spatial coherence of a light radiated in the light source; an optical condenser for condensing the radiated light passed through the optical diffuser into a spot where the optical fiber is located; a polarizer for polarizing the light passed through the optical condenser into a 45° linear polarized light from an axis of the optical fiber; a polarization analyzer, installed at 90° angle with respect to the polariscope and attached closely with the optical fiber, to prevent the penetration by the background image of the optical fiber; an optical fiber strain unit including a strain sensor for straining the optical fiber on the polarization analyzer toward a longitudinal direction and measuring the strain on the optical fiber; an object lens for magnifying the image of the light penetrated through the optical fiber; and a charge coupled device (CCD) array for measuring the penetration variation of the optical fiber caused from the strain caused by the optical fiber strain unit over the optical fiber.
摘要:
There is provided a dispersion-managed fiber preform and a fabricating method thereof preform by modified chemical vapor deposition (MCVD). A core and a clad having the refractive index distribution of an optical fiber with a positive dispersion value are uniformly deposited in a glass tube. The preform with the positive dispersion value is heated at every predetermined period with a torch and the heated preform portions are etched to have a negative dispersion value. Then, the preform alternately having positions with the positive dispersion value and positions with the negative dispersion value along the length direction is collapsed.
摘要:
An apparatus and method for measuring residual stress and photoelastic effect of an optical fiber is disclosed. The apparatus includes a rotating light diffuser for providing temporally averaged uniform image by restraining spatial coherence of light emitted from a light source to be completely scattered, a collecting lens for aligning the light passed through the rotating light diffuser in an optical fiber, a linear birefringence device for linearly controlling the polarization state of the aligned light input from the collecting lens, a condenser for condensing the light passed through the linear birefringence device on a place where the optical fiber is located, a fixed polarizer for transforming the polarization state of the light passed through the optical fiber to the intensity distribution by allowing the light emitted from the linear birefringence device to transmit the optical fiber, an objective lens for obtaining a magnified optical fiber image having the intensity distribution of the light transmitted the optical fiber, and a unit for measuring transmittance variation given to the optical fiber depending on locations.
摘要:
The present invention relates generally to an image tracking device in an optical communication system, and in particular, to a device and method for measuring the transverse characteristics, including the refractive index or residual stress of an optical fiber or a fiber preform.
摘要:
There are provided an optical fiber rod overcladding apparatus and method, and an optical fiber drawing method. In the preform rod overcladding method, a preform rod is clamped in a top chuck and leveled, and a glass tube is mounted in a bottom chuck and leveled. The preform rod is coaxially inserted into a glass tube. Then, the glass tube is preheated by the furnace and heated by the burner until the glass tube reaches a softening point. The preform rod is completely sealed in the glass tube by sucking air in a clearance between the preform rod and the glass tube by application of a negative vacuum pressure. Thus, a preform is completed.
摘要:
An optical fiber for maximizing residual mechanical stress and an optical fiber grating fabricating method using the optical fiber are provided. The optical fiber includes a core formed of silica, for propagating light, and a cladding formed of boron-doped silica, surrounding the core. Alternatively, the optical fiber includes a core formed of phosphorous-doped silica and a cladding formed of silica, surrounding the core.
摘要:
An optical fiber for maximizing residual mechanical stress and an optical fiber grating fabricating method using the optical fiber are provided. The optical fiber includes a core formed of silica, for propagating light, and a cladding formed of boron-doped silica, surrounding the core. Alternatively, the optical fiber includes a core formed of phosphorous-doped silica and a cladding formed of silica, surrounding the core.
摘要:
An erbium-doped optical fiber (EDF) and a fabricating method thereof The erbium-doped optical fiber has a core formed by substantially doping silica with erbium and having gratings formed therein at a predetermined period, for propagating light therethrough, and a cladding surrounding the core and having a lower refractive index than the core. Since the erbium-doped optical fiber acts as a gain flattening filter, an erbium-doped fiber amplifier formed out of the erbium-doped optical fiber obviates the need of splicing an erbium-doped optical fiber with a gain flattening filter.
摘要:
There is provided an apparatus and method for fabricating a holey optical fiber. An optical fiber with air holes of a predetermined size and shape along the length of the optical fiber is drawn by supplying nitrogen gas into air holes through one end of a holey optical fiber preform while heating the other end of the preform.