A mode-stripper for an optical fiber includes a water-cooled enclosure. A portion of an optical fiber to be mode-stripped is modified in a way which allows radiation to leak from cladding of the fiber. The optical fiber extends through the enclosure from a proximal end thereof to a distal end thereof, with the modified portion of the fiber within the enclosure. The fiber is fixedly held in the enclosure at the proximal end thereof and held at the distal end of the enclosure by an elastomeric diaphragm.

In a waveguide device, unnecessary optical power is appropriately terminated. According to an embodiment of the present invention, the waveguide device has a termination structure filled with a light blocking material to terminate light from a waveguide end. In the termination structure, a cladding and a core are removed to form a groove on an optical waveguide. The groove is filled with a material (light blocking material) that attenuates the intensity of light. Thus, light input to the termination structure is attenuated by the light blocking material, suppressing crosstalk which possibly effects on other optical devices. Thus, such a termination structure can restrain crosstalk occurred in optical devices integrated in the same substrate and can also suppress crosstalk which possibly effects on any other optical device connected directly to the substrate.

In a waveguide device, unnecessary optical power is appropriately terminated. According to an embodiment of the present invention, the waveguide device has a termination structure filled with a light blocking material to terminate light from a waveguide end. In the termination structure, a cladding and a core are removed to form a groove on an optical waveguide. The groove is filled with a material (light blocking material) that attenuates the intensity of light. Thus, light input to the termination structure is attenuated by the light blocking material, suppressing crosstalk which possibly effects on other optical devices. Thus, such a termination structure can restrain crosstalk occurred in optical devices integrated in the same substrate and can also suppress crosstalk which possibly effects on any other optical device connected directly to the substrate.

Disclosed herein are methods, structures, apparatus and devices for the termination of unused waveguide ports in planar photonic integrated circuits with doped waveguides such that free-carrier absorption therein may advantageously absorb any undesired optical power resulting in a significant reduction of stray light and resulting reflections.

An optically visualized anti-counterfeiting electronic integrated apparatus includes a housing, light sources and spectroscopic structures. The housing has tunnels each with an incident end and an exit end respectively present on opposite sides of the housing. The light sources are respectively configured to emit first lights with a first spectrum range. The spectroscopic structures are respectively disposed in the channels, and are respectively configured to separate second lights from the first lights to the exit ends, in which the second lights have a second spectrum range within the first spectrum range.

Structures for a photodetector or light absorber and methods of forming a structure for a photodetector or light absorber. The structure includes a pad, a waveguide core adjoined to the pad, and a light-absorbing layer on the pad. The waveguide core includes a first longitudinal axis, and the light-absorbing layer includes a second longitudinal axis and an end surface intersected by the second longitudinal axis. The end surface of the light-absorbing layer is positioned adjacent to the waveguide core. The first longitudinal axis of the first waveguide core is inclined relative to the second longitudinal axis of the light-absorbing layer and/or the end surface slanted relative to the second longitudinal axis.

An optical attenuator and/or optical terminator is provided. The device includes an optical channel having two regions with different optical properties, such as an undoped silicon region which is less optically absorptive and a doped silicon region which is more optically absorptive. Other materials may also be used. A facet at the interface between the two regions is oriented at a non-perpendicular angle relative to a longitudinal axis of the channel. The angle can be configured to mitigate back reflection. Multiple facets may be included between different pairs of regions. The device may further include curved and/or tapers to further facilitate attenuation and/or optical termination.

A light emitting device comprises a lightguide formed from a film with a core layer, a light emitting region, a light mixing region, at least one light source, and a light absorbing cladding region on at least one lateral edge of the core layer. In one embodiment, the cladding region is on the lateral edges of the core layer in the light mixing region. The light absorbing material in the cladding region may absorb light from the at least one light source propagating in the cladding region at an angle greater than 40 degrees to the optical axis. The difference in refractive index for the core material and cladding material may be between 0.001 to 0.01. The full angular width at half maximum intensity of light exiting the light emitting region may be less than 60 degrees in air in a first illumination plane.

Embodiments described herein include a waveguide combiner having an edge coated with an optically absorbent composition and a method of coating the edge of the waveguide combiner with the optically absorbent composition. The optically absorbent composition includes one or more types of nanoparticles or microparticles, at least one of one or more dyes or one or more pigments, and a polymer matrix of one or more binders. The method includes producing an optically absorbent formulation. The optically absorbent formulation includes one or more types of particles, at least one of one or more dyes or one or more pigments, one or more binders, and one or more solvents. The optically absorbent formulation is applied on an edge of a waveguide combiner using an edge blackening tool. The formulation is cured with radiation to form the optically absorbent composition.

The present disclosure relates to optical waveguide termination devices. In some embodiments, an optical waveguide termination device is coupled to an end of an optical waveguide. The optical waveguide termination device is a tapered structure. In various embodiments, an optical absorption rate of the tapered structure is increased to enhance a termination efficiency. The optical absorption is increased by highly-doped material, multi-layer structure, different cladding, and periodic structure. The enhancement of the termination efficiency benefits size reduction of the tapered structure.