A system that may include a radiation source to generate a beam of coherent radiation; traveling lens optics to focus the beam to generate multiple spots on a surface of a sample and to scan the spots together over the surface; collection optics to collect the radiation scattered from the multiple spots and to focus the collected radiation to generate a pattern of interference fringes; and a detection unit to detect changes in the pattern of interference fringes.

An interferometer has a first input configured to provide a first measurement beam at a first frequency, and a second measurement signal at the first frequency. The interferometer has a second input configured to provide a reference beam at a second frequency that is different than the first frequency; an optical element comprising a first portion comprising a polarization beam splitter; and a diffraction grating disposed over the optical element configured to diffract the first measurement beam and the second measurement beam.

There is provided retro-reflective interferometer device for detection and/or measurement of displacements and/or rotations and/or mechanical vibrations, the device includes a transceiver unit including at least one radiation source capable of emitting a radiation beam and at least one radiation receiver; a movable unit movably mounted with respect to said transceiver unit, the movable unit includes one or more movable elements that are susceptible to displacement and/or vibration by an external force; and at least one retro-reflective element capable of reflecting back the radiation beam to form a sequence of radiation patterns; and an analyzing element operationally associated with the radiation receiver for analyzing a displacement change, an intensity change and/or a frequency change in the sequence of radiation patterns. Further provided are systems including the device and methods utilizing the same.

A field detector (2) comprises a field-responsive element (10) which undergoes a dimensional change when exposed to a predetermined field; and an interferometric read-out arrangement arranged to detect the dimensional change of the field-responsive element. A light source (4) is arranged to provide a measurement beam reflected from the field-responsive element (10) and a reference beam not reflected from the field-responsive element (10), an optical detector (6) being disposed so as to detect at least part of an interference pattern produced by the measurement beam and the reference beam. The field-responsive element (10) has a shape comprising a curved surface and is constrained at least one edge (12) thereof such that the dimensional change causes the curved surface to be displaced in a direction which changes an optical path length of the measurement beam relative to the reference beam, thereby changing the interference pattern detected by said optical detector.

Provided is a super-resolution holographic microscope including a light source configured to emit input light, a diffraction grating configured to split the input light into first diffracted light and second diffracted light, a mirror configured to reflect the first diffracted light, a wafer stage arranged on an optical path of the second diffracted light and on which a wafer is configured to be arranged, and a camera configured to receive the first diffracted light that is reflected by the mirror and the second diffracted light that is reflected by the wafer to generate a plurality of hologram images of the wafer.

The optical angle sensor comprises a diffraction unit, a light source, a light receiving unit, and a plurality of reflection units. The diffraction unit includes a first diffraction part for generating combined light and a second diffraction part for diffracting a first light and a second light a plurality of times. The plurality of reflection units includes a first reflection unit, a second reflection unit, a third reflection unit that reflects the first light and the second light through the second diffraction part toward the second diffraction part, fourth reflection unit, and fifth reflection unit. The calculating unit, with the rotation of the diffraction unit, calculates the amount of change in the angle based on the change in the interference signal caused by the combined light generated on the light receiving surface.

There are provided devices, systems and methods utilizing interferometric retro-reflection displacement/vibration meter. In particular, there are provided laser interferometer devices, systems and methods for measuring three-axis small angle displacements and vibrations of a body.

A method for measuring a spatial distortion of a target surface (110) of a workpiece (110A). Light is transmitted twice through a reference pattern-generator (104) and impinged upon a workpiece pattern-generator (108). Then, with an optical detector (116), first and second beams formed by the light as a result of interaction with two pattern-generators (104) (106) is acquired to produce a signal characterizing geometry of interference fringes formed at the detector (116) by the first and second beams. Indicia representing at least one of a type and a value of spatial distortion of the target surface (110) is generated and recorded. A system embodying the implementation of the method.

A compensation optical unit (30) for a measurement system (10) for determining a shape of an optical surface (12) of a test object (14) by interferometry generates a measuring wave (44), directed at the test object, with a wavefront that is at least partly adapted to a target shape of the optical surface from an input wave (18). The unit includes first (32) and second (34) optical elements disposed in a beam path of the input wave. The second optical element is a diffractive optical element configured to split the input wave into the measuring wave and a reference wave (42) following an interaction with the first optical element. At least 20% of a refractive power of the entire compensation optical unit is allotted to the first optical element, and this allotted refractive power has the same sign as the refractive power of the entire compensation optical unit.

An optical sensor in which an optical component more inexpensive than a corner cube is used as a measurement target and which has accuracy similar to that of a case where the corner cube is used is provided. An optical sensor 1 includes a light source 2, a dividing unit 6, a retroreflection unit 4 that retroreflects first light and second light divided by the dividing unit 6, a combining unit 7, a light receiving unit 5, and a calculation unit 8. The retroreflection unit 4 includes a first retroreflector 4a that retroreflects the first light in parallel in an opposite direction of an incident direction of the first light by performing reflection thereof twice, a second retroreflector 4b that retroreflects the second light in parallel in an opposite direction of an incident direction of the second light by performing reflection thereof twice, and a third retroreflector 4c that retroreflects the first light, which is emitted from the first retroreflector 4a, to the first retroreflector 4a and retroreflects the second light, which is emitted from the second retroreflector 4b, to the second retroreflector 4b.