A quantitative phase microscopy (QPM) system and methods are provided for sample imaging and metrology in both transmissive and reflective modes. The QPM system includes a first illuminating beam propagating along a transmission-mode path and a second illuminating beam propagating along a reflection-mode path, a microscope objective lens disposed in the reflection-mode path, and a common-path interferometer comprising a diffraction grating, a Fourier lens, a pinhole, and a 2f system lens to collimate the reference beam and the imaging beam such that the collimated reference beam and imaging beam interfere with each other to form an interferogram at a final image plane.

An apparatus for light delivery to magneto-optical trap (MOT) system utilizes only planar optical diffraction devices including a planar-integrated-circuit PIC and a metasurface MS. When MOT is based on the use of a diffraction grating, a grating chip is additionally employed to launch and manipulate light for laser cooling. Bridging the gap between the sub-micrometer-scale guided mode on the PIC and the centimeter-scale beam needed for laser cooling, a magnification of the mode area by about 10.sup.10 is demonstrated using an on-chip extreme-mode-converter to launch a Gaussian mode into free space from a PIC-waveguide and a beam-shaping, polarization-dependent MS to form a diverging laser beam with a flat-top spatial profile, which efficiently illuminates the grating chip without loss of light. Comparison to equivalent Gaussian-beam-illuminated GMOTs evidences advantageous power efficiency of operation of the proposed light delivery system as compared with conventional systems employing Gaussian distribution of illumination at the grating chip.

A method for optical sensing includes providing a mirror comprising a central reflective region surrounded by a peripheral glare-suppressing region. A beam of light from a laser light source is directed to reflect from the central region so as to pass through an output optic along an axis toward a target scene. The light returned from the target scene through the output optic is focused onto an optical sensor, via collection optics having a collection aperture surrounding the mirror.

An internal laser component of an optical device comprises: a waveguide that defines a guided mode of a first optical wave characterized by a first propagation constant associated with a first effective refractive index. An optical antenna grating comprises: a waveguide that defines a guided mode of a second optical wave characterized by a second propagation constant associated with a second effective refractive index, and a grating structure configured to emit a portion of the second optical wave in a selected direction. The internal laser component and the optical antenna grating are configured to provide a relationship between the first effective refractive index and the second effective refractive index such that the selected direction is substantially insensitive to a change in a temperature of a thermal environment in which the internal laser component and the optical antenna grating are thermally coupled.

Configurations for a diffraction grating design and methods thereof are disclosed. The diffraction grating system can include an input waveguide located at a first location on or near a Rowland circle and multiple output waveguides located at a second and third location on or near the Rowland circle. The input waveguide may be located between the output waveguides and this configuration of input and output waveguides can reduce the footprint size of the device. In some examples, the optical component can function as a de-multiplexer. Additionally, the optical component may separate the input wavelength band into two output wavelength bands which are separated from one another by approximately 0.1 μm.

A method for optical sensing includes providing a mirror comprising a central reflective region surrounded by a peripheral glare-suppressing region. A beam of light from a laser light source is directed to reflect from the central region so as to pass through an output optic along an axis toward a target scene. The light returned from the target scene through the output optic is focused onto an optical sensor, via collection optics having a collection aperture surrounding the mirror.

A design method of a diffractive optical assembly, and a diffractive optical assembly. The design method comprises: S110, designing a first diffractive optical element according to a target light field; S120, simulating the first diffractive optical element to obtain a first light field difference between the simulation light field of the first diffractive optical element and the target light field; and S130, designing a second diffractive optical element according to the first light field difference. According to the design method, the performance of the diffractive optical assembly can be improved.

A diffraction grating includes a plurality of grating unit cells positioned in a periodic array on a substrate surface. In cross-section, a grating unit cell includes a homogeneous dielectric host medium with a first refractive index n.sub.1, embedding at least a first block of a first dielectric material with a second refractive index n.sub.2, a side edge of which is in direct contact with at least a second block of a second dielectric material with a third refractive index n.sub.3. Both the first block and the second block have a trapezoidal cross-section. The plurality of grating unit cells provides a non-symmetrical response for positive first diffraction order and negative first diffraction order based on nanojet hot spot positions, the nanojets being generated at edges between dielectric materials with different refractive indexes.

The present invention provides a projector including a laser module and a lens module, wherein the lens module includes a plurality of lens and a plurality of diffractive optical elements. In the operations of the projector, the laser module is arranged to generate at least one laser beam; each of the lenses is arranged to receive one of the at least one laser beam to generate a collimated laser beam; and the diffractive optical elements correspond to the lenses, respectively, and each of the diffractive optical elements is arranged to receive the collimated laser beam from the corresponding lens to generate an image. The images generated by the diffractive optical elements form a projected image of the projector. By using the projector of the present invention, the projected image may have higher resolution or field of view that is advantageous for the 3D sensing system.

An apparatus including a first substrate including a first incoupling diffractive optical element configured to couple light into the first substrate, and a first outcoupling diffractive optical element configured to output, from the first substrate, light that has been coupled into the first substrate; and a second substrate including a second incoupling diffractive optical element configured to couple light into the second substrate, and a second outcoupling diffractive optical element configured to output, from the second substrate, light that has been coupled into the second substrate; wherein the first and second incoupling diffractive optical elements are substantially inverse of each other and the first and second outcoupling diffractive optical elements are substantially inverse of each other.