Abstract: A temperature-compensated optical fiber component for use in high-density WDM optical communication includes an optical fiber which has a Bragg grating serving as a monochromatic filter, an inner package which supports the optical fiber and causes the Bragg grating to have a temperature-compensating capability, and an outer package arranged outside the inner package. A clearance having a heat insulating function is provided between the outer package and the inner package.

Abstract: An optical module comprises an optical fiber having a formed portion to form a fiber grating and a package to which the optical fiber is secured. The package comprises a single package member or at least two or more package members whose materials differ from each other. The optical fiber is secured to the package member. A distortion for adjusting a Bragg reflection wavelength of the fiber grating of the optical fiber is given to the package member.

Abstract: An optical module comprising: a comb-shaped package having a plurality of teeth portions and a base portion; and at least one optical fiber having fiber grating, wherein respective fiber-grating formed portions of at least one optical fiber are placed in corresponding teeth portions and base portion of said package, and the optical fiber is fixed to the base portion and corresponding teeth portion in such manner that the fiber-grating formed portion exists between the base portion and the corresponding teeth portion.

Abstract: An optical module for reducing the variance of grating spacing in an optical fiber comprises an optical fiber receiving portion having an optical fiber receiving portion and optical fiber securing portions for receiving and securing the optical fiber to the optical module, respectively. An adhesive agent containing filler and having an excellent water-vapor resistance is applied to the securing portions of the optical module for securing the fiber grating portion of the optical fiber to the optical module.

Abstract: Wavelength multiplex transmission is realized in which the temperature dependency of an EDFA is compensated for in relation to the wavelengths which are used. A first and a second long-period grating which have different periods from each other are formed in an optical fiber, ensuring that the peak wavelength of a waveform representing an optical transmission loss characteristic of the first long-period grating side is located on the shorter wavelength side than a transmission band and a peak wavelength of a waveform representing an optical transmission loss characteristic of the second long-period grating side is located on the longer wavelength side within the transmission band.

Abstract: An optical module comprising: a comb-shaped package having a plurality of teeth portions and a base portion; and at least one optical fiber having fiber grating, wherein respective fiber-grating formed portions of at least one optical fiber are placed in corresponding teeth portions and base portion of said package, and the optical fiber is fixed to the base portion and corresponding teeth portion in such manner that the fiber-grating formed portion exists between the base portion and the corresponding teeth portion.

Abstract: An optical module comprises an optical fiber having a formed portion to form a fiber grating and a package to which the optical fiber is secured. The package comprises a single package member or at least two or more package members whose materials differ from each other. The optical fiber is secured to the package member. A distortion for adjusting a Bragg reflection wavelength of the fiber grating of the optical fiber is given to the package member.

Abstract: An optical module for reducing the variance of grating spacing in an optical fiber comprises an optical fiber receiving portion having an optical fiber receiving portion and optical fiber securing portions for receiving and securing the optical fiber to the optical module, respectively. An adhesive agent containing filler and having an excellent water-vapor resistance is applied to the securing portions of the optical module for securing the fiber grating portion of the optical fiber to the optical module.

Abstract: A temperature-compensated optical fiber component for use in high-density WDM optical communication includes an optical fiber which has a Bragg grating serving as a monochromatic filter, an inner package which supports the optical fiber and causes the Bragg grating to have a temperature-compensating capability, and an outer package arranged outside the inner package. A clearance having a heat insulating function is provided between the outer package and the inner package.

Abstract: A grating type optical component is provided, in which a plurality of light beams having wavelengths different from one another can be reflected, the, loss is small, and the cost is low. The grating type optical component is composed of plural kinds of gratings (6a to 6d) that reflect different wavelengths of light and are formed at once in an optical fiber (2) and arranged serially in its longitudinal direction, so that there are no fusion splicing portions between the gratings. The plural kinds of serially-connected gratings (6a to 6d) are together housed in a temperature compensating package (3N) for compensating the temperature dependency of the gratings (6a to 6d). In forming the gratings (6a to 6d), prepare a phase mask (8N) in which a plurality of grating forming patterns (1a to 1d) different from one another are formed and arranged transversely. The phase mask (8N) covers the optical fiber (2) such that the grating forming patterns (1a to 1d) face the optical fiber (2).

Abstract: A grating type optical component is provided, in which a plurality of light beams having wavelengths different from one another can be reflected, the loss is small, and the cost is low. The grating type optical component is composed of plural kinds of gratings (6a to 6d) that reflect different wavelengths of light and are formed at once in an optical fiber (2) and arranged serially in its longitudinal direction, so that there are no fusion splicing portions between the gratings. The plural kinds of serially-connected gratings (6a to 6d) are together housed in a temperature compensating package (3N) for compensating the temperature dependency of the gratings (6a to 6d). In forming the gratings (6a to 6d), prepare a phase mask (8N) in which a plurality of grating forming patterns (1a to 1d) different from one another are formed and arranged transversely. The phase mask (8N) covers the optical fiber (2) such that the grating forming patterns (1a to 1d) face the optical fiber (2).

Abstract: Wavelength multiplex transmission is realized in which the temperature dependency of an EDFA is compensated for in relation to the wavelengths which are used. A first and a second long-period grating which have different periods from each other are formed in an optical fiber, ensuring that the peak wavelength of a waveform representing an optical transmission loss characteristic of the first long-period grating side is located on the shorter wavelength side than a transmission band and a peak wavelength of a waveform representing an optical transmission loss characteristic of the second long-period grating side is located on the longer wavelength side within the transmission band.

Abstract: The temperature dependency of an EDFA is compensated in a wavelength of 1570 to 1600 nm to realize a wavelength division multiplexing transmission. First and second long period gratings different in grating period from each other are formed in an optical fiber. The peak wavelength of the waveform of the light transmission loss characteristic of the first long period grating is formed on the shorter wavelength side than a transmission band. The peak wavelength of the waveform of the light transmission loss characteristic of the second long period grating is formed on the longer wavelength side than a transmission band.

Abstract: A grating-type optical component having a high isolation ability at a light-blocking band and a small clad layer mode combination loss at a signal transmission band, and its manufacturing method are provided. A selected area on a core of an optical fiber is irradiated by ultraviolet beams emitted from an excimer laser source through a phase mask in order to produce high index of refraction areas and low index of refraction areas arranged alternately and periodically along the longitudinal axis of the optical fiber. This ultraviolet irradiation is terminated before the index of refraction, which is increasing due to the ultraviolet irradiation, reaches a target value. Then, the phase mask is removed, and the selected area of the core is again irradiated by ultraviolet beams, thereby completing the grating-type optical fiber.

Abstract: An optical fiber which comprises a coating layer disposed outside a bare optical fiber having a core and a cladding and a grating formed in the core of the exposed bare optical fiber by removing the coating layer and its manufacturing method. The optical fiber is provided with a re-coating layer disposed in the exposed bare optical fiber.

Abstract: An optical fiber coupler in which portions in the lengthwise direction of a plurality of optical fibers whose surface is coated with a carbon film are welded to each other and extended to form a connected portion, and the connected portion is not coated with a carbon film. This coupler is manufactured by arranging in parallel a plurality of optical fibers whose surface is coated with a carbon film so that the portions which are to form a connected portion are brought into contact with each other, and by heating the portions which are to form a connected portion in an atmosphere containing oxygen to join these portions by welding while extending the optical fibers. This optical fiber coupler has high hydrogen resistance and static fatigue strength. Also, the use of this coupler provides a small-sized system as a whole without degrading the optical characteristics.