An on-chip wavefront sensor, an optical chip, and a communication device are disclosed. The on-chip wavefront sensor includes an antenna array configured for separating received spatial light to obtain a plurality of sub-light spots; a reference light source module configured for generating a plurality of intrinsic light beams; a phase shifter array configured for performing phase shifting processing on the intrinsic light beams to obtain reference light; and an optical detection module configured for performing coherent balanced detection according to the reference light and the sub-light spots to obtain a photocurrent corresponding to each of the sub-light spots.

A metrology apparatus (302) includes a higher harmonic generation (HHG) radiation source for generating (310) EUV radiation. Operation of the HHG source is monitored using a wavefront sensor (420) which comprises an aperture array (424, 702) and an image sensor (426). A grating (706) disperses the radiation passing through each aperture so that the image detector captures positions and intensities of higher diffraction orders for different spectral components and different locations across the beam. In this way, the wavefront sensor can be arranged to measure a wavefront tilt for multiple harmonics at each location in said array. In one embodiment, the apertures are divided into two subsets (A) and (B), the gratings (706) of each subset having a different direction of dispersion. The spectrally resolved wavefront information (430) is used in feedback control (432) to stabilize operation of the HGG source, and/or to improve accuracy of metrology results.

A method for performing optical wavefront sensing includes providing an amplitude transmission mask having a light input side, a light output side, and an optical transmission axis passing from the light input side to the light output side. The amplitude transmission mask is characterized by a checkerboard pattern having a square unit cell of size . The method also includes directing an incident light field having a wavelength to be incident on the light input side and propagating the incident light field through the amplitude transmission mask. The method further includes producing a plurality of diffracted light fields on the light output side and detecting, at a detector disposed a distance L from the amplitude transmission mask, an interferogram associated with the plurality of diffracted light fields. The relation

[00001]$0<L<\frac{1}{8}.Math.\frac{{}^2}{}.Math..Math.\mathrm{or}.Math..Math.\frac{1}{4}.Math.\frac{{}^2}{}.Math.\left(2.Math.n-1\right)<L<\frac{1}{4}.Math.\frac{{}^2}{}.Math.\left(2.Math.n+1\right)$

is satisfied, where n is an integer greater than zero.

Provided is a metalens array and a wavefront sensor system, and the metalens array includes: at least a metalens array unit; and the metalens array unit includes: a transmittive metalens array, the transmittive metalens array includes: a plurality of transmittive metalens at different working waveband, and the plurality of transmittive metalens have the same focal length and can be used for focusing incident lights of different wavelengths to different positions of a first plane. According to the present disclosure, a plurality of transmittive metalens with different working wavelengths may focus the light of different wavelengths at different positions in the focal plane and obtain the focal point offset of different wavelengths, so as to calculate wavefront of multiple wavelengths.

A device for analysing a wavefront may be connected to a fluorescence microscopy imaging system with optical sectioning, equipped with a microscope objective including a pupil in a pupil plane, the analysis device including a two-dimensional detector including a detection plane; a two-dimensional arrangement of microlenses, arranged in an analysis plane, each microlens forming, on the detection plane, when the analysis device is connected to the microscopic imaging system, an image of an object situated in a focal plane of the microscope objective, with a given analysis field; an optical relay system optically conjugating the analysis plane and the pupil plane; a field diaphragm positioned in a plane optically conjugated with the plane of detection, and defining said analysis field; a processing unit that determines, based on the set of images formed by the microlenses, a two-dimensional map of a characteristic parameter of the wavefront in said analysis plane.

An aero-optical disturbance measurement system includes a mirror supported by a gimbal for receiving a light beam from a light emitting source, reflecting the light beam to a first periscope fold mirror and therefrom reflecting the light beam directly to a second periscope fold mirror. A first concave off-axis paraboloid mirror receives the light beam reflected from second periscope fold mirror and therefrom a first fold mirror receives the light beam reflected directly from first concave off-axis paraboloid mirror. A second fold mirror receives the light beam reflected directly from the first fold mirror. A second concave off-axis paraboloid mirror receives the light beam reflected directly from second fold mirror which reflects the light beam to a fast steering mirror. A fine tracker camera coupled to an embedded processer receives portion of light beam from fast steering mirror. Embedded processor controls movement of fast steering mirror and gimbal.

A complex amplitude information measurement apparatus (10) according to the present invention includes pixel sensor groups for generating a difference from one pixel sensor group to another in the optical distance of object light traveling from a measurement object (100); a camera (15) provided with an image sensor for recording, with a single-shot exposure, the object light that has passed through or been reflected from the pixel sensor groups to obtain intensity information of the measurement object; and a computer (16) for computing, on the basis of the intensity information, phase information of the measurement object (100).

Sensors, devices, apparatus, systems and methods for replacing microlens arrays with one or more switchable diffractive waveplate microlens arrays for providing measurements of wavefronts and intensity distribution in light beams with high spatial resolution with a single optical radiation sensor. The device acts like a conventional Shack-Hartmann wavefront sensor when the microlens array elements are in focusing state, and the device performs light beam intensity profile characterization acting as a beam profiler when the optical power of lens array elements is switched off.

The present invention relates to a system and method for reconstruction of temporal wavefront changes for use in an optical system comprising: measuring the distribution function of the light intensity, e.g. the two-dimensional distribution function of the light intensity, in at least two different images taken at different times, wherein said images are taken in at least one optical plane, e.g. the same optical plane, of the optical system.

A method for performing optical wavefront sensing includes providing an amplitude transmission mask having a light input side, a light output side, and an optical transmission axis passing from the light input side to the light output side. The amplitude transmission mask is characterized by a checkerboard pattern having a square unit cell of size . The method also includes directing an incident light field having a wavelength to be incident on the light input side and propagating the incident light field through the amplitude transmission mask. The method further includes producing a plurality of diffracted light fields on the light output side and detecting, at a detector disposed a distance L from the amplitude transmission mask, an interferogram associated with the plurality of diffracted light fields. The relation $0<L<\frac{1}{8}\frac{{}^2}{}\mathrm{or}\frac{1}{4}\frac{{}^2}{}\left(2n-1\right)<L<\frac{1}{4}\frac{{}^2}{}\left(2n+1\right)$
is satisfied, where n is an integer greater than zero.