Abstract: Provided is a position locating instrument for a position locating method in which position locating instruments that transmit and receive light beams are arranged in series connection. The position locating instruments reduce error factors and improve measurement accuracy by providing all or some of necessary position and attitude parameters. The position locating instrument has at least one light emission port through which light from a wavelength-changeable light source is emitted; and at least one light receiving port that receives light emitted or reflected by an adjacent position locating instrument. The light emitted from the light emission port has a fanlike pattern and has an emission angle varying, as a monotonic function of a wavelength of the light, in a direction perpendicular to a direction in which the light spreads in the fanlike pattern.

Abstract: Provided is a swept light source including one end surface coupled to a wavelength filter constituted of a diffraction grating and an end mirror via a light deflector and another end surface including a gain medium facing an output coupling mirror and which configures a laser cavity between the end mirror and the output coupling mirror, wherein a drive voltage having an AC voltage on which a DC bias voltage is superimposed is output from a control voltage source of the light deflector to an electrode pair of an electro-optic crystal, light is radiated from a light emitter to the electro-optic crystal, and incident light from the gain medium incident along an optical axis perpendicular to a direction of an electric field formed by the control voltage is deflected in a direction parallel to the electric field, so that wavelength sweeping is performed.

Abstract: Provided is a swept light source including one end surface coupled to a wavelength filter constituted of a diffraction grating and an end mirror via a light deflector and another end surface including a gain medium facing an output coupling mirror and which configures a laser cavity between the end mirror and the output coupling mirror, wherein a drive voltage having an AC voltage on which a DC bias voltage is superimposed is output from a control voltage source of the light deflector to an electrode pair of an electro-optic crystal, light is radiated from a light emitter to the electro-optic crystal, and incident light from the gain medium incident along an optical axis perpendicular to a direction of an electric field formed by the control voltage is deflected in a direction parallel to the electric field, so that wavelength sweeping is performed.

Abstract: Provided is a position locating instrument for a position locating method in which position locating instruments that transmit and receive light beams are arranged in series connection. The position locating instruments reduce error factors and improve measurement accuracy by providing all or some of necessary position and attitude parameters. The position locating instrument has at least one light emission port through which light from a wavelength-changeable light source is emitted; and at least one light receiving port that receives light emitted or reflected by an adjacent position locating instrument. The light emitted from the light emission port has a fanlike pattern and has an emission angle varying, as a monotonic function of a wavelength of the light, in a direction perpendicular to a direction in which the light spreads in the fanlike pattern.

Abstract: In a patch type optical fiber sensor, an optical fiber (2) has at its part a fiber Bragg grating (3) and that part is fixed to a film (4) serving as a base to form a film-like detecting element. Opposite ends of that part are connected to optical cord (1) to protect the film-like detecting element. The detecting element is bonded to an object (9) to be detected by bonding agent or by welding.

Abstract: An optical circuit includes a light source having a low degree of polarization, an input section connected to the light source, and an output section connected to the input section. The input section has an optical waveguide incapable of maintaining a state of polarization. The output section has at least one optical waveguide having no branches. The optical waveguide having no branches has, in at least part thereof, an optical waveguide capable of maintaining a state of polarization.

Abstract: An optical circuit includes a light source having a low degree of polarization, an input section connected to the light source, and an output section connected to the input section. The input section has an optical waveguide incapable of maintaining a state of polarization. The output section has at least one optical waveguide having no branches. The optical waveguide having no branches has, in at least part thereof, an optical waveguide capable of maintaining a state of polarization.

Abstract: In a detection section using a fiber grating (FBG), both ends of the FBG are protected with resin coating and a coated part is adhered or mechanically clamped to fixed parts. A spring or a lever or both of these are connected to one end of this fixed part. This is used as a detection section to convert a variation of a physical quantity such as displacement, weight, pressure or acceleration applied to between the fixed parts to a variation of a reflected wavelength or a transmitted wavelength from a fiber grating and to output the variation of the reflected wavelength and transmitted wavelength.