A fiber optic probe is provided with a distal sampling end, a proximal end, and light delivery and collection paths therethrough. The probe includes a window disposed at the distal sampling end of the fiber optic probe, the window having a distal end and a proximal end. A lens is disposed near the proximal end of the window, the lens having a distal end, a proximal end, and an aperture. A light delivery optical fiber is provided having a distal end and a proximal end, the light rays being directed through the aperture. A collection optical fiber is provided in optical communication with the lens and the window. The probe may include a lens collection filter disposed between the window and the lens and an optical isolator provided within the aperture to optically isolate the light delivery path and the light collection path.

A fiber optic probe is provided with a distal sampling end, a proximal end, and light delivery and collection paths therethrough. The probe includes a window disposed at the distal sampling end of the fiber optic probe, the window having a distal end and a proximal end. A lens is disposed near the proximal end of the window, the lens having a distal end, a proximal end, and an aperture. A light delivery optical fiber is provided having a distal end and a proximal end, the light rays being directed through the aperture. A collection optical fiber is provided in optical communication with the lens and the window. The probe may include a lens collection filter disposed between the window and the lens and an optical isolator provided within the aperture to optically isolate the light delivery path and the light collection path.

The present disclosure relates more to mode mixing optical fibers useful, for example in providing optical fiber laser outputs having a desired beam product parameter and beam profile. In one aspect, the disclosure provides a mode mixing optical fiber for delivering optical radiation having a wavelength, the mode mixing optical fiber having an input end, an output end, a centerline and a refractive index profile, the mode mixing optical fiber comprising: an innermost core, the innermost core having a refractive index profile; and a cladding disposed about the innermost core, wherein the mode mixing optical fiber has at least five modes at the wavelength, and wherein the mode mixing optical fiber is configured to distribute a fraction of the light input at its input end from its lower-order modes to its higher-order modes.

A waveguide assembly comprising a first waveguide, and a second waveguide designed as a dielectric multimodal waveguide, and a waveguide transition for transmitting an electromagnetic wave between the first waveguide and the second waveguide, the waveguide transition having a dielectric waveguide piece which is between the first waveguide and the second waveguide. The dielectric waveguide piece is capable of guiding a smaller mode number than the second waveguide, at least in a front section, facing the first waveguide.

A display device may include a projector coupled to volume Bragg grating (VBG) based pupil-replicating lightguide. The projector may be a scanning projector or a display panel based projector. A lighting unit for the display panel may have spatially variant spectral composition selected to match angular and wavelength selectivity of the VBGs of the pupil-replicating lightguide, thereby improving light utilization efficiency of the display device. In scanning projector implementations, the center wavelength of the scanned light beam may be varied in coordination with the scanning, to achieve the same effect.

A fiber module (1B) according to the present disclosure includes an input-side optical fiber (11), an output-side optical fiber (12), a ferrule (20) in which the input-side optical fiber and the output-side optical fiber are insertable in both ends and a groove (32) is formed in a direction orthogonal to a longitudinal direction (D1) in the middle of the longitudinal direction, a dielectric multilayer film filter (30) inserted in the groove, and an input-side GI fiber (15) and an output-side GI fiber (16) joined by fusion to respective terminal portions of the input-side optical fiber and the output-side optical fiber. The dielectric multilayer film filter is interposed between an end surface (15f) of the input-side GI fiber and an end surface (16f) of the output-side GI fiber in the longitudinal direction.

Some embodiments of the disclosure provide an optical fiber Fabry-Perot sensor (1), and a manufacturing method thereof. According to an embodiment, the optical fiber Fabry-Perot sensor (1) includes a hollow tube body (10), a first optical fiber (20), and a second optical fiber (30). The hollow tube body (10) has a first tube body (11), a cavity portion (12), and a second tube body (13) sequentially arranged in an axial direction. The first optical fiber (20) is provided within the first tube body (11) in the axial direction and has a first light guide end face (21) provided within the cavity portion (12). The second optical fiber (30) is provided in the second tube body (13) in the axial direction and has a second light guide end face (31) provided within the cavity portion (12).

An apparatus includes an optical gain fiber having a core, a cladding surrounding the core, the core and cladding defining an optical gain fiber numerical aperture, and a multimode fiber having a core with a larger radius than a radius of the optical gain fiber core, a cladding surrounding the core, the core and cladding of the multimode fiber defining a multimode fiber stable numerical aperture that is larger than the optical gain fiber numerical aperture, the multimode fiber being optically coupled to the optical gain fiber so as to receive an optical beam propagating in the optical gain fiber and to stably propagate the received optical beam in the multimode fiber core with low optical loss associated with the optical coupling.

An optical device may include a fiber to provide a beam. The optical device may include a graded-index element to expand or magnify the beam. An input facet of the graded-index element may be adhered to an output facet of the fiber. The optical device may include an optical transformation element to transform the beam after the beam is expanded or magnified by the graded-index element. An input facet of the optical transformation element may be adhered to an output facet of the graded-index element.

Periscope assemblies are provided which have a light path that travels in a first plane along the first waveguide, a second plane along the second waveguide that is parallel to the first plane, and along a third plane along the third waveguide that intersects the first plane and the second plane. In some examples the periscope assembly includes first and second carriers comprising respective first and second waveguides and defining respective first and second cavities in which a third carrier comprising a third waveguide is disposed and optionally includes an optical component. In some examples, the cavities are defined in one or more carriers on a mating surface, on a side opposite to the mating surface, or on a side perpendicular to a mating surface.