Non-zero deflection angle may be effected by implementing the embodiments of the present disclosure to allow for directing projected energy to a desired region, such as a region closer to the energy directing surface.

One example includes an optical element. The optical element includes a first optical material structure comprising a first index of refraction across a frequency spectrum. The optical element also includes a second optical material structure configured to exhibit an index anomaly corresponding to a change in index of refraction from the first index of refraction to a second index of refraction across a portion of the frequency spectrum and a change from the second index of refraction to the first index of refraction along the frequency spectrum. The optical element further includes a diffractive interface corresponding to a non-planar material contact junction between the first optical material structure and the second optical material structure. The diffractive interface can be configured to manipulate in a predetermined manner an optical beam having an optical path through the diffractive interface and having a frequency in the portion of the frequency spectrum.

A method includes pressing a face of a stamp into a first portion of a replication material disposed on a substrate, to cause the replication material to have a predetermined characteristic, exposing the first portion of the replication material to illumination, to modify the first portion of the replication material, and subsequently removing a second portion of the replication material that was not exposed to the illumination. An optical device includes a substrate, a portion of replication material disposed on a first surface of the substrate, the portion of replication material forming one or more diffractive optical elements, and a masking layer disposed on a second surface of the substrate, the second surface being opposite the first surface, in which a sidewall of the replication material has a straight profile, and in which the masking layer defines an aperture aligned with the portion of the replication material.

A spectral beam combining system includes a plurality of input fibers and a prism having a curved input surface. The plurality of input fibers are attached to the curved input surface. The spectral beam combining system also includes an immersion grating defined on a second surface of the prism, a protective cap disposed over the immersion grating, and an output surface.

A diffractive network is disclosed that utilizes, in some embodiments, diffractive elements, which are used to shape an arbitrary broadband pulse into a desired optical waveform, forming a compact and passive pulse engineering system. The diffractive network was experimentally shown to generate various different pulses by designing passive diffractive layers that collectively engineer the temporal waveform of an input terahertz pulse. The results constitute the first demonstration of direct pulse shaping in terahertz spectrum, where the amplitude and phase of the input wavelengths are independently controlled through a passive diffractive device, without the need for an external pump. Furthermore, a modular physical transfer learning approach is presented to illustrate pulse-width tunability by replacing part of an existing diffractive network with newly trained diffractive layers, demonstrating its modularity. This learning-based diffractive pulse engineering framework can find broad applications in e.g., communications, ultra-fast imaging and spectroscopy.

A measurement apparatus which measures a relative positional displacement amount of a partial pattern to another pattern in a complex pattern on a surface of an object, includes: a measurement part to measure two-dimensional intensity distributions having a first and a second two-dimensional intensity distribution, the first distribution being formed by applying first light having a first shape to a region on which the complex pattern is measured and detecting only zero order diffraction light from the region via a first filter, and the second distribution being formed by applying second light having a second shape to the region and detecting only zero order diffraction light from the region via a second filter; a storage part to store measurement data indicating the distributions; and a calculation part to form a synthesized intensity distribution obtained by the two-dimensional intensity distributions to calculate a positional displacement amount of the partial pattern.

A projector includes a beam homogenizer receiving light from a light source and creating a predetermined illumination, and a spatial light modulator including grating stages to receive the predetermined illumination. Each grating stage may include a plurality of pixels where corresponding pixels in the grating stages are aligned with one another. Each of the pixels may include a liquid crystal layer disposed between two substrates, where a pixel is switchable by applying a voltage thereto, with a grating period of the pixel selected such that, when the voltage is applied to the pixel and light is passed therethrough, optical energy from the light in plus and minus first orders is deflected toward sides of the pixel and optical energy from a zero order of the light is allowed to pass through the pixel, with a polarization state of the light maintained through the pixel.

A LiDAR transmitter photonic integrated circuit (PIC) for scanning an environment over a field of view, FOV, the FOV having an azimuthal angular range and a polar angular range, the LiDAR transmitter PIC comprising: a light source for providing light from at least one laser, an optical switch having an input and a plurality of outputs, the optical switch being configured to selectively direct light received at the input to one of the plurality of outputs, and a light emitting component having a plurality of inputs and a plurality of emitters, the light emitting component configured to selectively emit beams over a plurality of emission angles having different respective polar components within the polar angular range of the FOV, wherein the light source is coupled to the input of the optical switch and each of the plurality of outputs of the optical switch is coupled to a respective one of the plurality of inputs of the light emitting component.

A multipass laser amplifier includes a mirror, a mirror device, a gain crystal, and refractive or diffractive beam-steering element. The gain crystal is positioned on a longitudinal axis of the multipass laser amplifier between the mirror and the mirror device. The beam-steering element is positioned on the longitudinal axis between the gain crystal and the mirror device. The beam-steering element has no optical power and deflects a laser beam, by refraction or diffraction, for each of multiple passes of the laser beam between the first mirror and the mirror device, such that each pass goes through the gain crystal for amplification of the laser beam and goes through a different respective off-axis portion of the beam-steering element. The no optical power of the beam-steering element enables maintaining a large beam size in the gain crystal, thereby facilitating amplification to high average power.

An optical pattern generation device includes: a first laser light source for emitting first laser light; a first diffractive optical element for changing a phase of the first laser light depending on a position on a plane perpendicular to a propagating direction of the first laser light, and emitting laser light having a phase distribution; a second diffractive optical element for changing a phase of incident laser light depending on a position on a plane perpendicular to a propagating direction of the incident laser light, and emitting laser light for forming an optical pattern; and a transfer optical system disposed between the first and second diffractive optical elements, for transferring the phase distribution of the laser light emitted from the first diffractive optical element to a phase distribution of laser light incident on the second diffractive optical element.