A position measurement system configured to measure a position of an object. The system includes an optical system to obtain a first measurement wave and a second measurement wave from a radiation source, and to allow the first and second measurement wave to at least partially interfere with each other after interaction of at least one of the first and second measurement wave with the object to form a first detection beam. The system further includes a first detector to receive the first detection beam. The system also has a processing unit configured to receive an output from the first detector and to determine a signal representative for the position of the object from the output, wherein the optical system includes a phase modulator configured to modulate a phase difference between the first measurement wave and the second measurement wave.

An integrated circuit that includes a wavelength meter is described. This integrated circuit may include: a set of interferometers having integer multiples of a phase or a delay, where the set of interferometers provide outputs corresponding to a range from an MSB to an LSB of a wavelength in an optical signal. For example, the set of interferometers may include MZIs or ring resonators. Moreover, the integrated circuit may include a converter that provides digital electrical signals that specify the range from the MSB to the LSB. Note that the set of interferometers may have different FSRs, where an interferometer that provides an output corresponding to the MSB has a largest FSR and a smallest phase or delay, and a second interferometer that provides a second output corresponding to the LSB has a smallest FSR and a largest phase or delay.

An actuator system configured to position an object, the actuator system includes a piezo actuator having an actuator contact surface. The piezo actuator is configured to exert a force via the actuator contact surface onto the object. The piezo actuator includes a transparent piezo material. The actuator system further has an optical position sensor configured to measure a position of the actuator contact surface. The optical position sensor is configured to transmit an optical beam through the transparent piezo material to the actuator contact surface. The optical position sensor may form an interferometer.

A cascaded interferometric system for Fourier domain optical coherence tomography (OCT) in which the output of one sub-system interferometer is directed through a second sub-system interferometer for performing the Fourier transform in hardware.

An asymmetric optical interferometry method, comprises the following steps: an incident light is split into two beams, and the two beams are respectively projected onto a surface of an object to be tested and a reference mirror; and then respectively pass through a first imaging lens having a larger area on the side of the object, and a second imaging lens having a smaller area on the side of the reference mirror, and overlap on a photoelectric sensor after passing through a third imaging lens to form at least one interference image (S1); the corresponding interference image is input into a computer to obtain a signal of the corresponding interference image (S2); parse the signal of the corresponding interference image to obtain a three-dimensional shape (S3) of the surface of the object. Also provide an asymmetric optical interferometry device.

An example embodiment may include an interferometer. The interferometer may include a multimode waveguide with an input waveguide optically coupled to a first side of the multimode waveguide, for feeding a light signal to the multimode waveguide. The interferometer may also include a first waveguide at one end optically coupled to a second side of the multimode waveguide, and at the other end terminated by a first waveguide mirror. The interferometer may also include a second waveguide at one end optically coupled to the second side of the multimode waveguide and at the other end terminated by a second waveguide mirror. The multimode waveguide may be adapted to distribute the light signal towards the first and second waveguide mirror via the first waveguide and via the second waveguide.

An alignment reference module (ARM) for detecting an alignment of a hologram with respect to a spindle axis of a spindle that supports an optic device under test (DUT). The hologram is employed for testing an optical surface of the DUT. The ARM includes a flat portion having a reflective surface for reflecting light back toward the hologram member to detect tilting of the hologram relative to the spindle axis. The ARM also includes a spherical portion having a reflective surface adjacent the flat portion for transmitting light back toward the hologram member to detect a radial position of the hologram relative to the spindle axis.

Optics for apodizing an optical imaging probe beam, and methods for fabricating optics for apodizing an optical imaging probe beam are provided. In some embodiments, optics for apodizing an electrical comprises: an optical fiber; a focusing element coaxially aligned with the optical fiber; an element having a cylindrical bore and an angled reflective surface, wherein a first portion of a beam focused by the focusing element enters the cylindrical bore and a second portion of the beam is reflected at an angle to produce a beam with a generally annular-shaped profile.

A system for the full-field interferential imaging of a sample, includes an illumination path with a light source, an interferometer with at least one first objective, and a separating element for receiving incident light waves via an input face and for forming an object arm for receiving the sample and a reference arm on which a reflection device is arranged, the reflection device being used to reflect incident light waves in a direction different from the direction of incidence. The separator element has a reflection coefficient and a transmission coefficient that are non-equal such that the proportion of the optical power of the incident light waves sent to the object arm is strictly larger than the proportion of the optical power of the light waves sent to the reference arm. The system also comprises a detection path comprising a two-dimensional image acquisition device, the illumination path and the detection path comprising a common path comprising \ input face of the separator element and being separated by a reflection element.

An interferometry system including a coherent light source operable to generate a beam of coherent light is provided. Separate waveguide pathways are optically associated between the coherent light source a photodetector. A transceiving segment can also be optically associated with each waveguide pathway at a location between the coherent light source and the photodetector. Each transceiving segment can be configured to emit an emitted beam of coherent light and positioned to receive a received portion of an emitted beam of coherent light emitted from a transceiving segment optically associated with a different waveguide pathway. The received portion of the emitted beam of coherent light can be combined with coherent light from the waveguide pathway receiving the received portion of the emitted beam of coherent light to form an optical interference signal. Accordingly, each waveguide pathway can be further configured to direct a separate optical interference signal toward a respective photodetector.