Abstract: The present invention connects two independent plastic optical fiber channels simultaneously, in which optic signals can be transmitted along two optic passes through a single mechanical rotational interface. The first channel of light path consists of a pair of plastic optic fibers with larger-core, co-axially fixed in 2 holders respectively. The light signal from one of the fiber can be directly coupled into another fiber. A number of smaller-core plastic optic fibers for second channel of light path are circumferentially arranged in the peripheral space of the first channel fibers. They are blind-spot free during rotation and are ideal for machine control applications such as SERCOS Interfaces. The rugged design permits underwater usage. Damaged fibers can be easily replaced without costly repairs of the device itself.

Abstract: An optical rotating data transmission device comprises a first collimator arrangement for coupling-on first optical waveguides, a second collimator arrangement for coupling-on second optical waveguides, which is supported to be rotatable relative to the first collimator arrangement about a rotation axis, and a derotating element such as a Dove prism in a light path between the collimator arrangements. At least one collimator arrangement comprises a deflecting element which deflects light entering the device from optical waveguides positioned at an angle to the direction of the rotation axis to travel along the direction of the rotation axis, or deflects light traveling along the direction of the rotation axis to exit the device at an angle to the rotation axis towards optical waveguides.

Abstract: An optical element including a transmitting surface section and at least one reflective surface section integrally formed on a main body of the optical element. The transmitting surface section refracts incident light emitted from a predetermined light-emitting position and transmits the light. The reflective surface section reflects the incident light emitted from the light-emitting position such that the light returns to a position differing from the light-emitting position. An optical axis of the transmitting surface section and an optical axis of the reflective surface section are out of alignment such as to be mutually parallel or mutually tilted.

Abstract: A beam coupler assembly for a fiber laser is disclosed. The assembly includes a housing having a sidewall with an interior surface, an exterior surface, a first end and a second end. A first seal extending from the interior surface of the tubular housing and dividing the housing into a first section and a second section is also provided. The first section and second section are environmentally isolated from one another. However, the first seal is substantially optically neutral. An input collimator unit received within the first end of the sidewall of the housing and into the first section and is releasably coupled thereto. An output collimator unit received within the second end of the sidewall of the housing and into the second section and is also releasably coupled thereto.

Abstract: A multi-channel fiber optic rotary joint has been invented in which optic signals can be transmitted simultaneously from a rotating fiber optic collimator array and a stationary fiber optic collimator array in air and in other optic fluids. A de-rotating lens, a cylindrical GRIN (Graded Index) lens, is positioned in the path between said rotating fiber optic collimator array and said stationary fiber optic collimator array, and arranged for rotation relative to each fiber optic collimator arrays at a rotary speed equal to one-half the relative rotational rate between said rotating and stationary fiber optic collimator arrays.

Abstract: [Object] An optical amplifier and a resonator capable of outputting output light having a high intensity are provided.

Abstract: An optical rotary joint comprises a first collimator arrangement for coupling-on first light-waveguides, and a second collimator arrangement for coupling-on second light waveguides, with the second collimator arrangement being supported to be rotatable relative to the first collimator arrangement about a rotation axis. At least one derotating optical element is provided in the light path between the first collimator arrangement and the second collimator arrangement. At least one collimator arrangement comprises a rod-shaped lens that is fastened on a support plate so that the axis of the lens is tilted at a given angle relative to the rotation axis of the rotary joint.

Abstract: An optical rotary joint comprises a first collimator arrangement for coupling-on first light-waveguides, and a second collimator arrangement for coupling-on second light waveguides, with the second collimator arrangement being supported to be rotatable relative to the first collimator arrangement about a rotation axis. At least one derotating optical element is provided in the light path between the first collimator arrangement and the second collimator arrangement. At least one collimator arrangement comprises a rod-shaped lens that is fastened on a support plate so that the axis of the lens is tilted at a given angle relative to the rotation axis of the rotary joint.

Abstract: An optical module includes a fiber array, a laser diode array, a photodiode array and a micro-lens array. The fiber array includes optical fibers which are divided to a transmitter group and a receiver group. The laser diode array includes laser diodes which are grouped in a transmitter group. The photodiode array includes photodiodes which are divided to a monitor group and a receiver group. The laser diode array is provided between the fiber array and the photodiode array. The optical fibers of the transmitter group are optically aligned with the laser diodes of the transmitter group, respectively. The micro-lens array is provided between the laser diode array and the photodiode array, and optically aligns the laser diodes of the transmitter group and the optical fibers of the receiver group with the photodiodes of the monitor group and the photodiodes of the receiver group, respectively.

Abstract: A resonator sensing device having an optics coupler device for communicating light between light source(s) and sensor(s) and a hollow core fiber resonator. Light from one resonator fiber tip is coupled to a second resonator fiber tip via a graded index (GRIN) lens having the appropriate pitch such that the maximum coupling efficiency is achieved and having two angled surfaces. The angled surfaces are coated with an appropriate coating having a reflectance R in order to achieve the desired degree of coupling. Light reflected by the second angled surface is captured with another lens (such as a microlens) and coupled to a third fiber segment (coupled port). The optical parameters for the GRIN lens and the microlens are tailored to have the least loss.

Abstract: The present invention discloses an improved optical device having at least a first and second optical components. The optical device further includes a first extending tube securely attached to the first and second optical components as a first building block wherein the first and second optical components are aligned and position adjusted in the position-holding-and-fixing means and securely attached thereto by a room-temperature UV curable epoxy UV cured at room temperature. The optical device then further assembled using a step-by-step building block assembling process with more building blocks assembled by optical components similar to the first building block described above. In other preferred embodiment, the first and second optical components held in the extending tube having a pre-aligned dihedral angle between the first and second optical components.

Abstract: A coherent light source includes a plurality of light emitting points arranged in one-dimensional array. A beam shaping unit shapes a light beam so that a diameter of a light emitted from the coherent light source in a direction perpendicular to a direction of the light emitting point array is larger than a diameter in the direction of the light emitting point array, and an intensity distribution of the light emitted from each of the light emitting points is uniform. A magnification of a focusing optical system is set such that a light emitted from the beam shaping unit is coupled to an optical fiber based on a maximum diameter of the light emitted from the beam shaping unit.

Abstract: A glass optical reflective tap is described that optically connects two optical fibers and may tap a portion of the light that is being communicated between the optical fibers. In one embodiment of the invention, the optical filter includes two D-lenses that operate as focusing or collimator lenses. The first D-lens focuses an optical signal onto a tap filter that allows a majority of the light within an optical signal to pass and also reflects a small portion of optical signal light to a reflective port. The second D-lens focuses the passed light into a transmission port of an optical fiber.

Abstract: A superlens for controlling the size and the phase of an electromagnetic beam that passes through it, and a method for independently controlling the horizontal and vertical focusing of the electromagnetic beam using the superlens is provided. The superlens comprises a vertically GRIN multi-layer structure with one or more horizontally curved sidewalls. The vertical focusing is controlled by varying the longitudinal thickness of the multi-layer structure. The horizontal focusing is controlled by varying the profile and the radius of curvature of the horizontally curved sidewalls. Varying the thickness and radius of curvature is done by etching. Also provided is a method for making the superlens.

Abstract: An optical intermediary component is suitable for guiding a light from an output optical path into an input optical path. The optical intermediary component includes a light guiding portion extending along a light axis. The light guiding portion has a light incident surface and a light emitting surface at two opposite ends thereof respectively. The light from the output optical path passes through the light incident surface and the light emitting surface of the light guiding portion in sequence, and is guided into the input optical path. The area of the light incident surface is greater than that of the light emitting surface. Therefore, a high assembly tolerance may reduce the manufacturing and assembly cost.

Abstract: A display system (100, 200, 300, 350, 400, 450) for displaying an image is described. The display system (100, 200, 300, 350, 400, 450) typically comprises one or a plurality of individual light sources (102) and a light collecting stage (110, 210, 310, 410) which comprises a separate light collecting sub-system associated with each light source (102), or group of light sources (102). The display system (100, 200, 300, 350, 400, 450) typically comprises at least one light modulator (120) which is operable to modulate light received from the light collecting stage (110, 210, 310, 410) according to an image which is to be displayed. Finally a projection stage (130) is provided for projecting the image, typically on a projection screen. The present invention also relates to a corresponding method. The present invention is especially useful with light sources having a packaging around the light emitting surface such that the light sources cannot be physically placed adjacent to each other.

Abstract: An optical device for collecting and distributing light from a quasi point light source which includes a planar light guide having surfaces through which optical axes are periodically spaced. There is at least one quasi point light source, the optical axis of each being coincident with the optical axes of the surfaces. There is also at least one optical element depressed within the edges or adjacent surfaces of the light guide at least partially rotated about the optical axis, and having a focal point at the quasi point light source.

Abstract: A glass optical reflective tap is described that optically connects two optical fibers and may tap a portion of the light that is being communicated between the optical fibers. In one embodiment of the invention, the optical filter includes two D-lenses that operate as focusing or collimator lenses. The first D-lens focuses an optical signal onto a tap filter that allows a majority of the light within an optical signal to pass and also reflects a small portion of optical signal light to a reflective port. The second D-lens focuses the passed light into a transmission port of an optical fiber.

Abstract: A POF includes an inner core having a refractive index distribution and an outer core provided on periphery of the inner core. A ratio Ra/Rb of an outer diameter of the inner core to the outer core satisfies 0.67?(Ra/Rb)?0.87 such that an outgoing beam from an end of the POF may have a parallel area of at least 200 ?m. Thus a space between the end for exiting the exit light and a light receiving device can be kept at least 200 mm without members or devices for collimating.

Abstract: In order to prevent a spectrum of a wavelength channel from becoming narrower, a device according to the present invention includes a light dividing section capable of dividing a wavelength spectrum in an input light beam and outputting a plurality of divided light beams, which are spatially separated and have wavelength spectrum portions different from each other, and a wavelength-to-special-position-converter capable of spatially multiplexing the wavelength spectrum portions of the plurality of divided light beams from the light dividing section.

Abstract: An optical module includes a fiber array, a laser diode array, a photodiode array and a micro-lens array. The fiber array includes optical fibers which are divided to a transmitter group and a receiver group. The laser diode array includes laser diodes which are grouped in a transmitter group. The photodiode array includes photodiodes which are divided to a monitor group and a receiver group. The laser diode array is provided between the fiber array and the photodiode array. The optical fibers of the transmitter group are optically aligned with the laser diodes of the transmitter group, respectively. The micro-lens array is provided between the laser diode array and the photodiode array, and optically aligns the laser diodes of the transmitter group and the optical fibers of the receiver group with the photodiodes of the monitor group and the photodiodes of the receiver group, respectively.

Abstract: A thin film interleaver device is disclosed. The thin film interleaver includes thin film optics. The thin film(s) are formed such that they reflect one group of wavelengths while allowing a second group of wavelengths to pass through the thin film(s). The thin film(s) exhibit a flat top frequency response across the channel bandwidths of the multiplexed signal for which the thin film filter is designed such that the thin film interleaver is less sensitive to wavelength drift and temperature variations.

Abstract: Planar lenses for integrated optics applications, in particular for use in optical touch screen sensors are disclosed. The disclosed planar lenses include a slab waveguide and an optical waveguide, preferably formed in unitary fashion, wherein the slab waveguide has a curved end face to focus light into or out of the optical waveguide, and wherein at least one additional lens is included within the slab waveguide. In one aspect of this disclosure, the additional lens is a diverging lens. In a second aspect the additional lens is a converging lens. The additional lens may match the acceptance angle of the optical waveguide to the curved end face of the slab waveguide. Alternatively, it may improve the tolerance of the planar lens to design or assembly errors and/or temperature variations. Preferably, the planar lenses are composed of a photo-patternable polymer, and the additional lenses are composed of air.

Abstract: An optical apparatus is made by mounting segments of a GRIN optical medium on a substrate in at least one groove thereon. The GRIN segments are longitudinally spaced apart from one another on the substrate, and are arranged so that a free-space optical beam received through the distal end face of the first GRIN segment is transmitted through the proximal end face of the first GRIN segment, propagates to the proximal end face of the second GRIN segment, is received through the proximal end face of the second GRIN segment, and is transmitted as a free-space optical beam through the distal end face of the second GRIN segment. The GRIN segments can be formed by division of a single GRIN optical medium mounted on the substrate.

Abstract: An optical apparatus comprises segments of a GRIN optical medium mounted on a substrate in at least one groove thereon. The GRIN segments are longitudinally spaced apart from one another on the substrate, and are arranged so that a free-space optical beam received through the distal end face of the first GRIN segment is transmitted through the proximal end face of the first GRIN segment, propagates to the proximal end face of the second GRIN segment, is received through the proximal end face of the second GRIN segment, and is transmitted as a free-space optical beam through the distal end face of the second GRIN segment. The GRIN segments can be derived from a single GRIN optical medium mounted on the substrate.

Abstract: A lighting device used in an image forming apparatus includes point light sources that emits rays; and a condensing body that is arranged in a direction of the rays emitted from the point light source and that condenses the rays on a surface of a document, which is placed on a contact glass, within a reading width in a sub-scanning direction of the document. The condensing body is arranged in a direction in which angles of all rays, which pass through the condensing body, are smaller than a critical angle of total reflection on the contact glass.

Abstract: According to one exemplary embodiment discussed herein, an active color wheel is provided. The active color wheel according to one exemplary embodiment includes a plurality of light sources configured to be moved through a period of motion. Further, the plurality of light sources are configured to be activated over a range of the period of motion.

Abstract: Techniques for designing optical devices with high isolation are disclosed. The high isolation is achieved by causing a reflected light signal to go through another filter. According to one embodiment, an optical apparatus comprises a first optical filter configured to transmit a first selected wavelength and reflect all other wavelengths, a second optical filter the second optical filter configured to transmit a second selected wavelength and reflect all other wavelengths. The first optical filter, being not perfect and producing a reflected signal with a residual of a signal at the first selected wavelength, the residual of the signal is minimized by the second optical filter when the reflected signal is impinged upon the second optical filter.

Abstract: A group delay compensation equalizer is disclosed that employs a single channel four-port WDM device for compensating the group delay experienced by a plurality of wavelengths transmitted over different paths. The transmission differential between two wavelengths is compensated by transmitting the two wavelengths through two different paths where the fiber length in reflecting the second wavelength is equal to the transmission time difference between the two wavelengths. The single channel four-port group delay equalizer effectively provides a unidirectional signal flow, as compared to the conventional equalizer that transmits optical signals bi-directionally. The present invention reduces the cost of a group delay equalizer by simplifying the use of multiple three-port WDM devices into a single channel four-port WDM device.

Abstract: An optical transmission system (1) alters quantity of incident light by reflecting an optical signal by a micro mirror (11) to enter an optical fiber (13) and by controlling an angle of the micro mirror (11), so that attenuation of the optical signal is controlled. An optical filter (14) is disposed between the micro mirror (11) and the optical fiber (13), for correcting a relationship between a control angle or control voltage of the micro mirror (11) and attenuation of the optical signal to be close to a linear relationship.

Abstract: An illumination apparatus illuminating an objective illumination region comprises a plurality of illuminants having light-emitting surfaces radiating diffused light, an illuminant substrate in which the illuminants are disposed so as to be set in array on the circumference, at least one optical member configured to guide the diffused light to the objective illumination region, a movable section configured to drive the optical member so as to be rotatable around the center of the circumference serving as a rotation center, and a lighting control section configured to control a light-emitting timing of the plurality of illuminants. The movable section and the lighting control section operate together such that the quantity of light per unit time of the diffused light guided to the objective illumination region is within a predetermined range.

Abstract: A fiber optic connector uses an expanded light beam design in a universal receptacle that couples to a single style of plug on the ends of all harnesses. A single, mirror image socket design is used on bulkhead receptacles or box connections, with which two harness plugs mate. The receptacle uses optical lenses for expanding, collimating, and focusing the beam from the plug terminii. The optical lens may comprise rod lenses, ball lenses, or any other optical component that accomplishes the desired beam manipulation with the required diameters and lengths. The optical components are captured in a sleeve that holds the components, establishes the distance between the plug terminii and the lenses, and provides the alignment needed between the plug ferrules and the optical components.

Abstract: A multiplexing optical system includes collimator lenses, a first condensing lens, a second condensing lens and an optical fiber. The collimator lenses collimate divergent laser beams that have been emitted from semiconductor lasers. The first condensing lens condenses laser beams transmitted through the collimator lenses in only one of a plane including the stripe width direction of the semiconductor lasers and a plane including a direction perpendicular to the stripe width direction. The second condensing lens condenses laser beams transmitted through the first condensing lens. The optical fiber is arranged in such a manner that the condensed laser beams enter the optical fiber. In the multiplexing optical system, an anamorphic lens is used as the second condensing lens, and the anamorphic lens condenses the laser beams in the two planes in cooperation with the first condensing lens.

Abstract: An optical module 1 comprises a first optical element F1, a first light receiving subassembly PD1, a second optical element F2, a second light receiving subassembly PD2, a light emitting subassembly LD3 for generating light, and a light transmitting part 3 optically coupled to the first optical element. The light emitting subassembly LD3, the first optical element F1, the second optical element F2 and the first light receiving subassembly PD1 are arranged along a predetermined plane S1. The light emitting subassembly LD3, the first optical element F1, the second optical element F2, and the second light receiving subassembly PD2 are arranged along another predetermined plane S2. The predetermined plane S1 intersects at a predetermined angle with the other predetermined plane S2.

Abstract: A WDM coupler includes a first collimator including a single fiber pigtail, a first GRIN lens and a first glass holding tube; a second collimator including a dual fiber pigtail, a second GRIN lens and a second glass holding tube; an optical filter arranged on an end surface of the second GRIN lens of the second collimator; an outer glass sleeve bridging the first and second collimators; and UV-curing epoxy between the outer glass sleeve and the glass holding tubes of the first and second collimators for securing the first and second collimators to the outer glass sleeve. The expansion coefficient of the UV-curing epoxy is matched to that of the glass materials of the outer glass sleeve and the first and second holding tubes, so that the first and second collimators can directly be fixed in the outer glass sleeve using the UV-curing epoxy.

Abstract: Disclosed herein is an illumination system for use in display systems employing spatial light modulators. The illumination system comprises a fastening mechanism for securing the bonding of the walls of the light integrator of the illumination system. A heat dissipation mechanism can be alternatively provided for reducing the temperature of the illumination system by dissipating the heat thereof.

Abstract: Methods for optical isolation in high peak power fiber-optic systems prevent damage to a facet within a fiber-optic isolator caused by back-reflected light from, for example, an optical amplifier. Preventing damage to the facet may include expanding a mode area of the back-reflected light and/or reducing a change in refractive index.

Abstract: An optical rotary joint comprises a first collimator arrangement for coupling-on first light-waveguides, and a second collimator arrangement for coupling-on second light waveguides, with the second collimator arrangement being supported to be rotatable relative to the first collimator arrangement about a rotation axis. At least one derotating optical element is provided in the light path between the first collimator arrangement and the second collimator arrangement. At least one collimator arrangement comprises a rod-shaped lens that is fastened on a support plate so that the axis of the lens is tilted at a given angle relative to the rotation axis of the rotary joint.

Abstract: An optical power monitor comprising a pig-tail fiber and a GRIN lens opposed to each other with a spacing and each having an end face (angled face) angled with respect to the axis, being low on reflection loss and able to be easily assembled. The pig-tail fiber and the GRIN lens are fixed in respective sleeves having axial end faces adhered to each other. At least one of the pig-tail fiber and the GRIN lens has an arc-segmental end face directed in its axial direction at the tip of its angled face. The arc-segmental end face is positioned in the same plane as the axial end face of the sleeve of the one. The axis of the sleeve of the one is kept vertical to the axial end face of the sleeve of the one. It can be prevented that the axial tip of the other enters the sleeve of the one and comes into contact with an inner wall of the sleeve of the one. Therefore, the assembling man-hours needed to adjust their relative positions can be reduced, and the assembling yield can be improved.

Abstract: A fiber optic array is miniaturized in a configuration that includes an input collimator, a first birefringence crystal, a waveplate, a Faraday rotator, a second birefringence crystal and a second collimator. The elements are aligned along a common optical axis. A light beam along the optical axis that is passed through the first collimator emerges off of the optical axis and through the remaining elements. It re-emerges from the fiber optic array on axis. The configuration provides substantial attenuation in a backward direction.

Abstract: An end face structure of an optical fiber includes a coreless fiber fused to an emitting end face of the fiber optical fiber and a coating material disposed around at least the coreless fiber, a refractive index of the coating material being higher than a refractive index of the coreless fiber.

Abstract: In a wavelength selective optical device, a lens for transmitting multiplexed optical signals having a plurality of wavelengths is provided to face an end of a first optical fiber such that light output from the end of the first optical fiber is converted into parallel light, and an optical filter is provided at a location to which the parallel light output from the lens is input. A second optical fiber is provided at a location in which the light reflected from the optical filter is input to the lens again to be focused by the lens. The lens is configured by bonding the ends of two gradient index rod lenses having different refractive index distribution constants and the substantially same outer diameter to each other to align their optical axes to each other.

Abstract: An apparatus and method to operate on a light beam by using a lens that collimates the light beam to a collimated beam with at least one cross-sectional dimension less than a critical dimension of 400 ?m or less over a working range WR. The apparatus has a bulk electro-optic material of small thickness ?, e.g., less than 300 ?m positioned within working range WR and the collimated beam traverses it along its path. The apparatus has a voltage source for applying a low operating or drive voltage Vdrive, e.g. less than 400 V to the bulk electro-optic material for performing an operation on the collimated beam. The lens for collimating the light beam is a free-space collimator such as a graded index (GRIN) lens or preferably a C-lens. The apparatus is a versatile and scalable platform that can be employed in building various electro-optic devices.

Abstract: An optical device fabrication method capable of fabricating optical devices with high precision and reliability in a simple process and at a low cost. The method of splicing a first optical device and a second optical device to fabricate a third optical device includes the steps of: (a) starting heating of an end surface of the first optical device to soften the end surface; (b) pushing the second optical device into the softened end surface to splice the first optical device and a joint surface of the second optical device to each other; (c) pulling back the second optical device to arrange the joint surface of the second optical device onto or outside of the end surface of the first optical device; and (d) terminating heating of the end surface to fix the first and second optical device spliced to each other.

Abstract: A method for making a high-power fused collimator, and a fused collimator made thereby, are provided. A fused collimator is provided that includes an end of a stripped end portion of an optical fiber fused to a proximal face of a silica lens. In an embodiment, a joint formed by the fiber end and the silica lens proximal face is substantially surrounded with a solder glass in a melted form. A cross-sectional area of the solder glass decreases proximally from a distal edge adjacent the lens to a proximal edge located along the fiber's stripped end portion. The solder glass is permitted to harden, forming a fused collimator. In another embodiment, a ferrule surrounds the fiber stripped end portion, and an adhesive is applied to the ferrule's proximal face to surround the fiber. The lens-ferrule joint is surrounded with solder glass, which is then surrounded with a silica sleeve.

Abstract: The invention relates to wavelength-selective optical filters for allowing light of a narrow optical spectral band, centered around a wavelength (?c) to pass through them, while reflecting the wavelengths lying outside this band. According to the invention, the transfer function (T1,2(?)) of the component is defined by multiplying two transfer functions of spectrally offset Fabry-Perot filters.

Abstract: The invention relates to an optical component including an optical fiber with a lens constituted by a single-mode optical fiber and a graded index optical fiber and a method of manufacturing the same. The invention provides an optical component in which an optical fiber with a lens can be accurately mounted on a substrate and which has high performance and highly stable manufacturability. An optical component has three V-shaped grooves for disposing optical fibers. An optical fiber with a lens is disposed in each of the V-shaped grooves. The optical component has a positioning mark using for positioning optical fiber connecting surfaces. The positioning mark extending across the V-shaped grooves in an orthogonal relationship therewith is provided. The positioning mark is formed line a concave groove and is visually perceived as two parallel straight lines when viewed in a direction normal to the surface on which the V-shaped grooves are formed.

Abstract: An image display device includes an image processing unit, a light source assembly, an optical modulator assembly, and a projection lens assembly. The image processing unit is configured to receive a video signal and generate image data and control signals. The light source assembly and optical modulator assembly are each controlled by the control signals such that the light source assembly generates illumination in a spatial distribution pattern that is coupled to optical modular assembly via a homogenizing device. The projection lens assembly is configured to project an image from the optical modulator assembly onto a viewing surface. The optical modular assembly is configured to maximize the amount of illumination coupled from the light source assembly, and includes at least one optical modulator surface configured to have a substantially 1:1 aspect ratio.

Abstract: An optical fiber sensor enabling simpler detection of a state of an external environment and a measuring apparatus using the same are provided. At a front end of an optical fiber portion 20a for transmitting the light a hetero core having a different diameter from that of a core of the optical fiber portion 20a is melt bonded so as to form a tip type optical fiber sensor 9 having a sensor portion 4 comprised of the hetero core on its front end. An end of the optical fiber portion 20a side of this tip type optical fiber sensor 9 has a light source 1 connected to it. Returned light striking the optical fiber portion 20a from the light source 1 and subjected to interaction with a measurement medium MD at the sensor portion 4 is split by an optical fiber coupler 2 and received at a photodiode or spectrum analyzer 6, thereby an optical fiber sensor measuring apparatus 100 is constructed.

Abstract: A multilayer optical fiber coupler for coupling optical radiation between an optical device and an optical fiber, including a first layer that has a fiber socket formed by photolithographic masking and etching to extend through said first layer, and a second layer bonded to the first layer. The first layer may comprise substantially single-crystal silicon. An optical fiber is inserted into the fiber socket to align the optical fiber precisely within the fiber socket. In one embodiment the optical fiber is a single mode fiber, and an optical focusing element formed on the second layer is aligned with the core of the single mode fiber. The second layer may comprise glass having an index of refraction that approximately matches the index of the optical fiber, and an optical epoxy is used to affix the optical fiber into the fiber socket and fill the gaps between the end face of the fiber and the second layer.