An imaging apparatus for conveying a virtual image including a waveguide having first and second surfaces. An in-coupling diffractive optic and an out-coupling diffractive optic arranged along one of the first and second surfaces, wherein the in-coupling diffractive optic is operable to direct image-bearing light beams into the waveguide for propagation by total internal reflection, and wherein the out-coupling diffractive optic is operable to direct at least a portion of the image-bearing light beams from the waveguide through the second surface toward an eyebox. An at least partially transparent outer cover located adjacent to the first surface, and a circular polarizer arranged between the waveguide and the outer cover, wherein the circular polarizer is operable to circularly polarize at least a portion of image-bearing light beams transmitted through the first surface and to prevent at least a portion of image-bearing light beams transmitted through the first surface from reentering the waveguide as a result of reflection from the outer cover.

A phase decoding method and apparatus for quantum key distribution based on reflection with an orthogonal rotation of polarization, and a corresponding system. The method comprises: splitting an input optical pulse of an arbitrary polarization state into two optical pulses by a beam splitter; and, transmitting the two optical pulses respectively along two optical paths, with a relative time delay applied to them, and then reflecting them back to the beam splitter respectively by two reflecting devices to be combined and output by the beam splitter. A phase modulation is performed on at least one of the two optical pulses according to a quantum key distribution protocol, and two orthogonal polarization states of the optical pulse are reflected with an orthogonal rotation of polarization, so that each orthogonal polarization state of the optical pulse, after being reflected by the corresponding reflecting device, is transformed to a polarization state orthogonal thereto.

An imaging apparatus for conveying a virtual image superimposed within a view of an ambient environment has a waveguide having first and second surfaces. An in-coupling diffractive optic on one of the planar surfaces is disposed to direct image-bearing light beams into the waveguide. An out-coupling diffractive optic on one of the planar surfaces of the waveguide is disposed to direct the image-bearing light beams from the waveguide toward a viewer eyebox. An outer cover protects as least part of the waveguide from undesirable environmental influences of an ambient environment while supporting views of the ambient environment from the eyebox. A circular polarizer interposed between waveguide and the outer cover blocks the return of stray light into the waveguide.

The present invention discloses an optical path length adjusting device, having a body, an optical path moving shaft, and an optical path adjusting screw, an auxiliary rod, and a connecting plate. By adjusting the optical path moving shaft, the optical path adjusting rod, and the auxiliary rod, and the connecting plate, the optical path can be adjusted after the light injected from the optical fiber into the optical path adjusting device. The present invention further comprises at least a bearing to stably drive a single direction of movement. The optical path length adjusting device will not cause angular deviation in the process of adjusting the optical path.

An imaging apparatus for conveying a virtual image superimposed within a view of an ambient environment has a wave-guide having first and second surfaces. An in-coupling diffractive optic on one of the planar surfaces is disposed to direct image-bearing light beams into the waveguide. An out-coupling diffractive optic on one of the planar surfaces of the waveguide is disposed to direct the image-bearing light beams from the waveguide toward a viewer eyebox. An outer cover protects as least part of the waveguide from undesirable environmental influences of an ambient environment while supporting views of the ambient environment from the eyebox. A circular polarizer interposed between waveguide and the outer cover blocks the return of stray light into the waveguide.

A high-order optical fiber multi-wavelength filter includes a polarization beam splitter configured to form a polarization-diversity loop configuration by splitting light received from a broadband light source into two polarization components, combining circulated and input light of the two polarization components, and outputting the combined light, a pair of polarization controllers each including at least one wave plate in combination, and configured to change a polarization state of input light, and a pair of polarization-maintaining fibers configured to form interference spectrums by assigning phase differences through birefringence.

A high-order optical fiber multi-wavelength filter includes a polarization beam splitter configured to form a polarization-diversity loop configuration by splitting light received from a broadband light source into two polarization components, combining circulated and input light of the two polarization components, and outputting the combined light, a pair of polarization controllers each including at least one wave plate in combination, and configured to change a polarization state of input light, and a pair of polarization-maintaining fibers configured to form interference spectrums by assigning phase differences through birefringence.

The present disclosure relates to an optical system of augmented reality glasses with a saw tooth-type partial reflector array which projects image light and external image light to user's eyes with a high transmittance. To this end, the optical system of augmented reality glasses includes a display device 30 which generates image light; a polarization element 311 which is opposite to be parallel to the display device 30 and determines a polarized component of S-pol or P-pol; a lens 312 which is provided at one side of the polarization element 311 and magnifies and focuses the image light passing through the polarization element 311 to form a focal surface in the waveguide 32; and a lens 312 which is provided at one side of the polarization element 311 and focuses image light passing through the polarization element 311; and a waveguide 32 which allows the image light to be incident from the lens 312 and expand an exit pupil of the incident image light to a horizontal direction to be emitted toward the user 15, in which the waveguide 32 includes: a first surface 322 and a second surface 323 which allow the image light to be incident to be totally reflected and are parallel to each other; an incident surface 321 which forms a predetermined incident angle ?i with the first surface 322; a partial reflector array 324 which is provided on the first surface 322 and the second surface 323 and has a saw tooth structure formed by alternately providing the transmissive surface 324a through which the totally reflected image light is transmitted and the reflective surface 324b through which the transmitted image light is reflected; and a polarization coating layer 325 which is formed on the saw tooth structure and has an angular bias that shows different reflectance according to the incident angle at which the light is incident on the transmissive surface 324a or the reflective surface 324b.

An imaging apparatus for conveying a virtual image including a waveguide having first and second surfaces. An in-coupling diffractive optic and an out-coupling diffractive optic arranged along one of the first and second surfaces, wherein the in-coupling diffractive optic is operable to direct image-bearing light beams into the waveguide for propagation by total internal reflection, and wherein the out-coupling diffractive optic is operable to direct at least a portion of the image-bearing light beams from the waveguide through the second surface toward an eyebox. An at least partially transparent outer cover located adjacent to the first surface, and a circular polarizer arranged between the waveguide and the outer cover, wherein the circular polarizer is operable to circularly polarize at least a portion of image-bearing light beams transmitted through the first surface and to prevent at least a portion of image-bearing light beams transmitted through the first surface from reentering the waveguide as a result of reflection from the outer cover.

A combined-wave (multiplexing) laser source of the present invention has an optical fiber; a plurality of laser sources 1a-1c that are in-place in a preset interval with regard to each other and which respectively emit laser light, a birefringent element 3 that separates spatially an incident laser light to an ordinary ray and an extraordinary ray and outputs separated rays every respective laser lights, and a convergence lens 4 that collects the ordinary ray and the extraordinary ray separated by said birefringent element relative to the respective laser lights and converges the rays to the optical fiber.