An optical scanning device includes: a first waveguide that propagates light by total reflection; and a second waveguide. The second waveguide includes: a first multilayer reflective film; a second multilayer reflective film that faces the first multilayer reflective film; and a first optical waveguide layer directly connected to the first waveguide and located between the first and second multilayer reflective films. The first optical waveguide layer has a variable thickness and/or a variable refractive index and propagates the light transmitted through the first waveguide. The first multilayer reflective film has a higher light transmittance than the second multilayer reflective film and allows part of the light propagating through the first optical waveguide layer to be emitted to the outside. By changing the thickness of the first optical waveguide layer and/or its refractive index, the direction of the part of the light emitted from the second waveguide is changed.

An optical scanning device includes: a first waveguide that propagates light by total reflection; and a second waveguide. The second waveguide includes: a first multilayer reflective film; a second multilayer reflective film that faces the first multilayer reflective film; and a first optical waveguide layer directly connected to the first waveguide and located between the first and second multilayer reflective films. The first optical waveguide layer has a variable thickness and/or a variable refractive index and propagates the light transmitted through the first waveguide. The first multilayer reflective film has a higher light transmittance than the second multilayer reflective film and allows part of the light propagating through the first optical waveguide layer to be emitted to the outside. By changing the thickness of the first optical waveguide layer and/or its refractive index, the direction of the part of the light emitted from the second waveguide is changed.

Light recycling within a waveguide is achieved by mode conversion instead of resonance. A structure is provided in in which light makes multiple passes through the same waveguide by converting the mode to a different mode after each pass and rerouting the light back into the same waveguide. The structure includes a bus waveguide and at least one mode converter device disposed at or adjacent each of two opposing ends of the bus waveguide, wherein each mode converter devices is configured to receive light having a receiving mode along a first direction and to cause light having a different mode from the receiving mode to propagate in a second direction opposite the first direction.

Light recycling within a waveguide is achieved by mode conversion instead of resonance. A structure is provided in in which light makes multiple passes through the same waveguide by converting the mode to a different mode after each pass and rerouting the light back into the same waveguide. The structure includes a bus waveguide and at least one mode converter device disposed at or adjacent each of two opposing ends of the bus waveguide, wherein each mode converter devices is configured to receive light having a receiving mode along a first direction and to cause light having a different mode from the receiving mode to propagate in a second direction opposite the first direction.

An optical device includes a first waveguide that propagates light in a first direction; and a second waveguide including a first mirror, a second mirror, and an optical waveguide layer. The first mirror extends in the first direction and has a first reflecting surface, and the second mirror extends in the first direction and has a second reflecting surface. The optical waveguide layer is located between the first and second mirrors and propagates the light in the first direction. A forward end portion of the first waveguide is disposed inside the optical waveguide layer. In a region in which the first and second waveguides overlap each other when viewed in a direction perpendicular to the first reflecting surface, at least part of the first waveguide and/or at least part of the second waveguide includes at least one grating whose refractive index varies periodically in the first direction.

An input-coupler of an optical waveguide couples light corresponding to the image and having a corresponding FOV into the optical waveguide, and the input-coupler splits the FOV of the image coupled into the optical waveguide into first and second portions by diffracting a portion of the light corresponding to the image in a first direction toward a first intermediate-component, and diffracting a portion of the light corresponding to the image in a second direction toward a second intermediate-component. An output-coupler of the waveguide combines the light corresponding to the first and second portions of the FOV, and couples the light corresponding to the combined first and second portions of the FOV out of the optical waveguide so that the light corresponding to the image and the combined first and second portions of the FOV is output from the optical waveguide. The intermediate-components and the output-coupler also provide for pupil expansion.

An input-coupler of an optical waveguide couples light corresponding to the image and having a corresponding FOV into the optical waveguide, and the input-coupler splits the FOV of the image coupled into the optical waveguide into first and second portions by diffracting a portion of the light corresponding to the image in a first direction toward a first intermediate-component, and diffracting a portion of the light corresponding to the image in a second direction toward a second intermediate-component. An output-coupler of the waveguide combines the light corresponding to the first and second portions of the FOV, and couples the light corresponding to the combined first and second portions of the FOV out of the optical waveguide so that the light corresponding to the image and the combined first and second portions of the FOV is output from the optical waveguide. The intermediate-components and the output-coupler also provide for pupil expansion.

In various embodiments, a beam-parameter adjustment system and focusing system alters a spatial power distribution of a radiation beam, via thermo-optic effects, before the beam is coupled into an optical fiber or delivered to a workpiece.

In various embodiments, a beam-parameter adjustment system and focusing system alters a spatial power distribution of a radiation beam, via thermo-optic effects, before the beam is coupled into an optical fiber or delivered to a workpiece.

An optical sensing system is presented for monitoring one or more parameters or conditions of an object. The optical sensing system comprises: an elongated light guide configured for placing in proximity of the object, the light guide defining a cavity for light propagation therethrough along at least one light propagation path, and having a light input port and at least one light output port; and a detector system for receiving light propagating from the at least one light output port, the detector system being configured and operable for monitoring a signal modulated by light interaction with the object and being indicative of the at least one parameter/condition of the object.