An optical system configured as part of optical metrology unit used to assess the operational status of a workpiece and, in a specific case, configured as an encoder head of a lithographic exposure tool. The optical system is devoid of a stand-alone optical corner-cubes and includes, instead, a single, imperfect or frustrated cuboid of optically-isotropic material that, in operation with the diffraction grating of the workpiece, simultaneously forms four interferometric signals for measuring x-, y, and z-positions of the workpiece grating relative to the optical system. Proposed system and method solve problems of (i) structural complexity of a conventional metrology unit for use in an exposure tool, (ii) burdensome alignment of the multitude of optical prisms in the process of forming such metrology unit, and (iii) cyclic non-linear errors associated with measurements involving conventional corner-cubes-based metrology units.

Various embodiments set forth a foveated display system and components thereof. The foveated display system includes a peripheral display module disposed in series with a foveal display module. The peripheral display module is configured to generate low-resolution, large field of view imagery for a user's peripheral vision. The foveal display module is configured to perform foveated rendering in which high-resolution imagery is focused towards a foveal region of the user's eye gaze. The peripheral display module may include a diffuser that is disposed within a pancake lens, which is a relatively compact design. The foveal display module may include a Pancharatnam-Berry Phase grating stack that increases the steering range of a beam-steering device such that a virtual image can be steered to cover an entire field of view visible to the user's eye.

The layered generation of at least one volume grating in a recording medium by way of exposure, the recording medium having at least one photosensitive layer which is sensitized for a presettable wavelength of the exposure light. Each volume grating is generated in the recording medium by at least two wave fronts of coherent light capable of generating interference, the wave fronts being superposed in the recording medium at a presettable depth, at a presettable angle and with a presettable interference contrast. The depth and the thickness of the refractive index modulation and/or transparency modulation of a volume grating in the recording medium is controlled by depth-specific control of the spatial and/or temporal degree of coherence of the interfering wave fronts in the direction of light propagation.

A near-eye display device is provided, including a display light source, a rotation module and a refractive amplification component. The rotation module rotates around the rotation center axis. The rotation module is provided with a light source scanning component and a mirror group. The light source scanning component converts the light of some pixel points of the display light source into radial propagation, and then the light is emitted through the mirror group and the refractive amplification component. The light source scanning component turns the light of some pixel points of the display light source into radial propagation, so that the optical path becomes radial direction from axial direction, and increases the optical path distance without increasing the volume of the device, which is conducive to reducing the thickness and volume of the device.

According to an embodiment, an optical MEMS transducer includes a diffraction structure including alternating first reflective elements and openings arranged in a first plane, a reflection structure including second reflective elements and configured to deflect with respect to the diffraction structure, and an optical element configured to direct a first optical signal at the diffraction structure and the reflection structure and to receive a second optical signal from the diffraction structure and the reflection structure. The second reflective elements are arranged in the first plane when the reflection structure is at rest. Other embodiments include corresponding systems and apparatus, each configured to perform various embodiment methods.

An optical projection system includes: a laser emitter configured to emit a beam along an emission axis; an optical element having an optical axis non-parallel to the emission axis, the optical element having a back focal length; and a folding optic configured to redirect the beam toward the optical axis, the beam following a folded optical path having: a first section along the emission axis from the laser emitter to the folding optic; and a second section along the optical axis from the folding optic to the optical element, the sum of the lengths of the first and second sections being equal to the back focal length, the length of the first section being a function of a divergence of the beam and the back focal length, and the folding optic having a height along the optical axis configured to redirect substantially the entire beam emitted by the laser emitter.

Hybrid imaging systems incorporating conventional optical elements and metasurface elements with light sources and/or detectors, and methods of the manufacture and operation of such optical arrangements are provided. Systems and methods describe the integration of apertures with metasurface elements and refractive optics with metasurface elements in illumination sources and sensors.

Provided is a laser processing method including overlapping a plurality of plate-shaped members that include a first plate-shaped member disposed on one end side of an overlapping direction and a second plate-shaped member disposed on the other end side of the overlapping direction; branching a laser beam into a first branched laser beam and a second branched laser beam; irradiating the first plate-shaped member with the first branched laser beam and the second branched laser beam in a state where the first branched laser beam and the second branched laser beam are emitted in parallel; forming line-shaped melting portions on the first plate-shaped member by moving the branched laser beams in a direction intersecting a direction in which the branched laser beams are aligned; and joining overlapped plate-shaped members in a state where the melting portion formed by using the first branched laser beam and the melting portion formed by using the second branched laser beam are connected to each other in the second plate-shaped member and the melting portions do not penetrate the second plate-shaped member.

An optical guide has at least two diffraction gratings in serial in front of a light source in order to diffract a light beam from the light source twice. The first diffraction grating could split the light beam into several parallel light beams along a first axis, and the second diffraction grating could split the light beams into several points of light along a second axis, and so on and so forth. By rotating the diffraction gratings relative to one another and by adjusting the distance between the diffraction gratings, a user of the optical guide could adjust the angle of the axis points and adjust a relative distance of the points of light relative to one another. These light beams could provide convenient guides for users in a variety of applications.

Machining device comprising an optical trepanation head (1), comprising an opto-mechanical system having a head body (21) provided with a rotating device (22), a picosecond or femtosecond pulsed laser source (3), and at least one optical fiber (4) wherein the rotation device (22) of the opto-mechanical system (2) comprises a rotative diffraction grating (R1). Machining process by means of optical trepanation using such a device.