An illumination optical apparatus illuminates a pattern on a mask with illumination light. The illumination optical apparatus includes an optical integrator arranged in an optical path of the illumination light, and a polarization member made of optical material with optical rotatory power, which is arranged in the optical path on an incidence side of the optical integrator, and which changes a polarization state of the illumination light. The illumination light from the polarization member is irradiated onto the pattern through a pupil plane of the illumination optical apparatus.

An eyewear device includes a lightguide having a world-side surface and an eye-side surface, a display oriented to emit light toward the lightguide, and a beam steering element that includes a first polarization grating positioned along an optical path between the display. The first polarization grating diffracts light emitted by the display into orders having different polarizations and the orders are selectively conveyed into different eyeboxes. The eyewear device also includes a frame that supports the lightguide, the display, and the first polarization grating. In some cases, the different polarizations include a right circular polarization or a left circular polarization and the beam steering element includes a polarization dependent filter that filters right circularly polarized light in a first state and left circularly polarized light in a second state.

An apparatus for sorting orbital angular momentum eigenstates of one or more photons includes at least one transformation PBOE configured to sort orbital angular momentum eigenstates of the one or more photons, at least one phase correction PBOE configured to sort spin angular momentum eigenstates of the one or more photons. A method for sorting orbital angular momentum eigenstates of one or more photons includes using at least one transformation PBOE to sort orbital angular momentum eigenstates of the one or more photons, and using at least one phase correction PBOE to sort spin angular momentum eigenstates of the one or more photons.

Disclosed herein are various improvements in optical switching engines. In one aspect, a range of switching engines includes various multiple bounce, multiple image devices, such as, for example, the Herriott Cell and the Robert Cell. In another aspect, liquid crystal spatial light modulators (SLMs) are used in the switching engine of an optical cross-connect. In another aspect, polarization gratings (PGs) are used in the switching engine. In another aspect, a switching engine includes a Fourier cell using SLMs with more than two states. Alternative imaging optics in a Fourier cell implementing a multiple-bounce, multiple image device are also disclosed.

The present invention provides a measuring apparatus for measuring a shape of an object to be measured, comprising an emitting unit configured to emit pattern light, an optical system configured to guide the pattern light emitted from the emitting unit to the object, a deflection unit arranged between the optical system and the object and configured to deflect the pattern light emitted from the optical system, an image sensing unit configured to capture the object via the optical system and the deflection unit, and a processing unit configured to determine the shape of the object based on an image of the object captured by the image sensing unit, wherein the deflection unit comprises a diffraction grating configured to diffract the pattern light emitted from the optical system.

Systems, methods, and apparatus are disclosed for attenuating an incident polarized light beam using a plurality of LCPGs and one or more switchable liquid crystal layers. When four LCPGs are used, a spacing between first and second LCPGs can be equal to a spacing between third and fourth LCPGs. Pi and FCL cells can also be used in place of more traditional LC switches. Switching of the LC switch can be imparted via an AC bias.

A single-fiber bidirectional optical transceiver module of the same wavelength. A sub-wavelength grating and a Faraday rotator are used, and the same element is reused to implement a polarization multiplex/de-multiplex function, so as to implement transmission and receiving of an optical signal in a small space. The single-fiber bidirectional optical transceiver module has less optical elements, a compact structure, and low cost, meeting the needs on a miniaturized, integrated, and high speed optical transceiver module for a modern optical communication system.

There is provided an illumination device having: a laser; a waveguide including at least first and second transparent lamina; a first grating device for coupling light from the laser into a TIR path in the waveguide; a second grating device for coupling light from the TIR path out of the waveguide; and a third grating device for applying a variation of at least one of beam deflection, phase retardation or polarization rotation across the wavefronts of the TIR light. The first second and third grating devices are each sandwiched by transparent lamina.

A light diffraction element, that has cells, includes first regions and second regions. Each of the cells comprises one of the first regions and one of the second regions. Each of the first regions has a thickness or a refractive index that is independently set. The second regions have a uniform thickness or a uniform refractive index. The first regions allow first polarized components of signal light to pass through. The second regions allow second polarized components of signal light to pass through. The second polarized components are different, in polarization direction, from the first polarized components. The light diffraction element performs optical computing by causing the first polarized components of signal light that have passed through the first regions to interfere with each other. The first polarized components of signal light output from the light diffraction element indicate information after the optical computing.

A waveguide display includes a waveguide and a staircase structure coupled to the waveguide. The waveguide includes a first substrate, a second substrate, and a holographic material layer between the first substrate and the second substrate. The holographic material layer includes a first grating and a second grating. The staircase structure is positioned on top of at least a portion of the first grating but not on top of the second grating. The staircase structure includes an input grating that is on top of the first grating and is configured to couple display light into the waveguide. The first grating is configured to redirect the display light coupled into the waveguide by the input grating towards the second grating.