Systems, devices and methods for measuring surface roughness and surface shape of an optical element using a dual-mode interferometer are disclosed. The devices implement optical filters, with a compact form, that allows measurement of both surface characteristics without rearranging the system components. One example interferometric system includes a laser light source and a low coherence light source that alternatively provide light to a collimator, followed by a polarizer, and a polarizing beam splitter. The system further includes two optical filters, a quarter waveplate, two objectives and a reference optical component. Each light source produces a set of interferograms, where one set of interferograms is used to measure the surface shape and another set of interferograms is used to measure the surface roughness of the optical component.

In a general aspect, a photonic quantum network is disclosed. In some implementations, microwave modes and optical modes are generated on first and second quantum processing units (QPUs) by operation of a first transducer device of the first QPU and a second transducer device of the second QPU. The microwave modes are transmitted within the first and second QPUs from the first and second transducer devices to respective first and second qubit devices. The optical modes are transmitted from the first and second QPUs to an interferometer device. By operation of the interferometer device, output signals are generated on respective output channels based on the optical modes from the first and second QPUs. Based on the output signals detected by operation of photodetector devices coupled to the respective output channels, quantum entanglement transferred to the first and second qubit devices by the microwave modes is identified.

An operation method of an image capture device includes steps as follows. The MEMS driver is controlled through the field programmable gate array (FPGA) independently to adjust at least one micro electro mechanical system (MEMS) scanning mirror of the optical system; at least one digital signal provided by the linear image sensor module is processed through the FPGA directly so as to obtain at least one image data.

A measuring apparatus (10; 110; 210; 310; 410; 510; 610; 710) for interferometric determination of a property (50; 52) of a shape (50) of a test surface (12) of an object under test (14) comprises an irradiation device (22) for generating an input wave (24), a splitting module (18; 118; 318; 418; 518) configured to generate, from the input wave, two plane waves (32, 34) with parallel directions of propagation and with an offset from one another across the directions of propagation, a wavefront adaptation module (20; 720) for generating two measurement waves (44, 46) by adapting the respective wavefront of the plane waves with an offset from one another to a target shape of the optical test surface, and a detector (56) for capturing at least one interferogram (64) generated by superposition of the measurement waves (44r, 46r) following their interaction with the test surface.

Disclosed herein are embodiments of a broadband wavemeter system comprising: a laser source to generate an optical signal having one or more wavelengths; a tap to separate a portion of the optical signal from the laser source; a splitter to split an incoming optical signal from the tap into a plurality of outgoing optical signals; a plurality of wavemeters, each one in the plurality to receive one of the outgoing optical signals from the splitter, in which each wavemeter in the plurality of wavemeters comprises a Mach-Zehnder Interferometer (MZI), and each wavemeter has at least one of free spectral range (FSR) detuning and center wavelength detuning, and a control circuit to collate outputs from individual ones of the plurality of wavemeters to monitor, detect and control the laser source.

A projection exposure tool for microlithography for imaging mask structures of an image-providing substrate onto a substrate to be structured includes a measuring apparatus configured to determine a relative position of measurement structures disposed on a surface of one of the substrates in relation to one another in at least one lateral direction with respect to the substrate surface and to thereby simultaneously measure a number of measurement structures disposed laterally offset in relation to one another.

A optical measurement apparatus includes: an optical system which generates a pupil image of a measurement target, using light; a polarization generator which generates a polarized light from the light; a self-interference generator which generates a plurality of beams divided from the pupil image, using the polarized light, and causes the plurality of beams to interfere with each other to generate a self-interference image; and an image analysis unit configured to extract phase data from the self-interference image, and to move the measurement target to a focus position on the basis of the phase data.

The invention relates to a lithography system comprising an optical column, a moveable target carrier for displacing a target such as a wafer, and a differential interferometer module, wherein the interferometer module is adapted for emitting three reference beams towards a first mirror and three measurement beams towards a second mirror for determining a displacement between said first and second mirror. In a preferred embodiment the same module is adapted for measuring a relative rotation around two perpendicular axes as well. The present invention further relates to an interferometer module and method for measuring such a displacement and rotations.

Methods are known for implementing general optical functions using wave splitters. However, these methods rely on these wave splitters having maximal extinction ratio, which is difficult to achieve in practice. The present invention provides methods for automatically adjusting wave splitters to provide maximal extinction ratio.

A method and system for instantaneous time domain optical coherence tomography (iTD-OCT) provides instantaneous optical depth profiles in an axial direction to a sample having scattering properties or that is at least partially reflective. An iTD-OCT instrument includes a spectroscopic detector having an internal optical axis and an array of detector pixels. A reference beam having a fixed optical path length is superpositioned along the optical axis with a measurement beam that includes back-scattered photons from the sample. The detector pixels capture a time domain interference pattern arising within the spectroscopic detector due to optical path length differences between photons from the reference beam and photons from the measurement beam. The iTD-OCT instrument may be implemented as a robust solid-state device with no moving parts.