There are disposed two homogenizers for controlling an irradiation energy density in the longitudinal direction of a laser light transformed into a linear one which is inputtted into the surface to be irradiated. Also, there is disposed one homogenizer for controlling an irradiation energy density in a width direction of the linear laser light. According to this, the uniformity of laser annealing can be improved by the minimum number of homogenizers.

Laser irradiation apparatus

A fiber grating pressure sensor includes an optical sensing element (20, 600) which includes an optical fiber (10) having a Bragg grating (12) impressed therein which is encased within and fused to at least a portion of a glass capillary tube (20) and/or a large diameter waveguide grating (600) having a core and a wide cladding and which has an outer transverse dimension of at least 0.3 mm. Light (14) is incident on the grating (12) and light (16) is reflected from the grating (12) at a reflection wavelength μ1. The sensing element (20, 600) may be used by itself as a sensor or located within a housing (48, 60, 90, 270, 300). When external pressure P increases, the grating (12) is compressed and the reflection wavelength μ1 changes.

Bragg grating pressure sensor

A method of forming waveguides, refractive index distributions and optical couplings automatically by light incidence, and devices obtained thereby. A non-linear optical material which has excellent properties of a large degree of freedom for an optical circuit substrate composition, etc. is used for optical circuit devices and optical circuit substrates. A photoelectric device containing an organic conjugated polymer film is deposited on a substrate by vapor deposition polymerization as at least one function layer. An optical network is provided with optical wiring for exchanging signals between processing elements selected from electronic elements, electronic apparatuses, electrooptical elements and electrooptical apparatuses.

Method of producing optical waveguide system, optical device and optical coupler employing the same, optical network and optical circuit board

A tube-encased fiber grating includes an optical fiber (10) having at least one Bragg grating (12) impressed therein which is embedded within a glass capillary tube (20). Light (14) is incident on the grating (12) and light (16) is reflected at a reflection wavelength μ1. The shape of the tube (20) may be other geometries (e.g., a 'dogbone' shape) and/or more than one concentric tube may be used or more than one grating or pair of gratings may be used. The fiber (10) may be doped at least between a pair of gratings (150, 152), encased in the tube (20) to form a tube-encased compression-tuned fiber laser or the grating (12) or gratings (150, 152) may be constructed as a tunable DFB fiber laser encased in the tube (20). Also, the tube (20) may have an inner region (22) which is tapered away from the fiber (10) to provide strain relief for the fiber (10), or the tube (20) may have tapered (or fluted) sections (27) which have an outer geometry that decreases down to the fiber (10) and provides added fiber pull strength. Also, the tube encased grating (12) exhibits lower mode coupling from the fiber core to the cladding modes due to the increased diameter of the cladding where the tube (20) is fused to the fiber (10) where the grating is located (12).

Tube-encased fiber grating

A device which simultaneously maximizes light reflectivity from one side of the device while maximizing light transmissivity from the opposite side of the device. The device is configured with distinct regions of transparency and reflectivity including a plurality of reflective structures. The structures are generally smaller towards a light transmitting side of the device and larger towards a light reflective side of the device.

Device having reflective and transmissive properties

The photorefractive effect results in a change in the refractive index of bulk chalcogenide glass when it is exposed to certain wavelengths of light, in particular, sub-band-gap light. The effect results in a variety of device structures including a fiber optic faceplate; an optical waveguide; a fiber tap; a lens and a Bragg grating. Methods for fabricating the various devices are described.

Lee M. Cook

Papers

Photorefractive effect in bulk chalcogenide glass and devices made therefrom

Photorefractive effect in bulk glass and devices made therefrom