G01J9/02

FULL-FIELD METROLOGY TOOL FOR WAVEGUIDE COMBINERS AND META-SURFACES
20230046330 · 2023-02-16 ·

Embodiments described herein provide for metrology tools and methods of obtaining a full-field optical field of an optical device to determine multiple metrology metrics of the optical device. A metrology tool is utilized to split a light beam into a first light path and a second light path. The first light path and the second light path are combined into a combined light beam and delivered to the detector. The detector measures the intensity of the combined light beam. A first equation and second equation are utilized in combination with the intensity measurements to determine an amplitude and phase Ψ at a reference point directly adjacent to a second surface of the at least one optical device.

Method and device for generating (quasi-) periodic interference patterns

Example embodiments relate to methods and devices for generating (quasi-) periodic interference patterns. One embodiment includes a method for generating an interference pattern using multi-beam interference of electromagnetic radiation. The method includes computing a set of grid points in a complex plane representing a grid with a desired symmetry. The method also includes selecting a radius of a virtual circle. Additionally, the method includes selecting a set of grid points in the complex plane that lies on the virtual circle centered around a virtual center point. Further, the method includes associating an argument of each grid point of the selected set of grid points in the complex plane with a propagation direction of plane waves or quasi plane waves or parallel wave fronts. In addition, the method includes obtaining the interference pattern that is a superposition of the plane waves or quasi plane waves or parallel wave fronts.

Method and device for generating (quasi-) periodic interference patterns

Example embodiments relate to methods and devices for generating (quasi-) periodic interference patterns. One embodiment includes a method for generating an interference pattern using multi-beam interference of electromagnetic radiation. The method includes computing a set of grid points in a complex plane representing a grid with a desired symmetry. The method also includes selecting a radius of a virtual circle. Additionally, the method includes selecting a set of grid points in the complex plane that lies on the virtual circle centered around a virtual center point. Further, the method includes associating an argument of each grid point of the selected set of grid points in the complex plane with a propagation direction of plane waves or quasi plane waves or parallel wave fronts. In addition, the method includes obtaining the interference pattern that is a superposition of the plane waves or quasi plane waves or parallel wave fronts.

HIGH PRECISION WAVELENGTH MEASUREMENT AND CONTROL OF A TUNABLE LASER
20180010967 · 2018-01-11 ·

A tunable laser system includes a tunable laser to be scanned over a range of frequencies and an interferometer having a plurality of interferometer outputs. At least two interferometer outputs of the plurality of interferometer outputs have a phase difference. A wavelength reference has a spectral feature within the range of frequencies, and the spectral feature does not change in an expected operating environment of the tunable laser. Processing circuitry uses the spectral feature and the plurality of interferometer outputs to produce an absolute measurement of a wavelength of the tunable laser and controls the tunable laser based on a comparison of the absolute measurement of the wavelength of the tunable laser with a setpoint wavelength.

Measurement apparatus of wavefront and polarization profile of vectorial optical fields

An apparatus measures the transverse profile of vectorial optical field beams, including both the phase and the polarization spatial profile. The apparatus contains a polarization separation module, a weak perturbation module, and a detection module. Characterizing the transverse profile of vector fields provides an optical metrology tool for both fundamental studies of vectorial optical fields and a wide spectrum of applications, including microscopy, surveillance, imaging, communication, material processing, and laser trapping.

High bandwidth quantum random number generator

An optical device for a quantum random number generator comprising: a source of phase randomised pulses of light, the source of phase randomised pulses of light further comprising a plurality of gain-switched lasers, each gain-switched laser having an output, and each gain-switched laser being configured to emit a stream of pulses such that the phase of each pulse in the stream of pulses is randomised, and an optical pulse combiner, the optical pulse combiner being configured to receive streams of pulses from the output of each gain-switched laser, combine the streams of pulses with one another into a combined stream of pulses and direct the combined stream of pulses into at least one output of the optical pulse combiner, the at least one output of the optical pulse combiner being the output of the source of phase randomised pulses of light; wherein the source of phase randomised pulses of light is configured such that the streams of pulses of light emitted by the plurality of gain-switched lasers are temporally offset relative to one another, a phase measurement element, the phase measurement element being configured to receive the combined stream of pulses from the output of the source of phase randomised pulses of light; and an optical detector, the optical detector being optically coupled to the phase measurement element.

High bandwidth quantum random number generator

An optical device for a quantum random number generator comprising: a source of phase randomised pulses of light, the source of phase randomised pulses of light further comprising a plurality of gain-switched lasers, each gain-switched laser having an output, and each gain-switched laser being configured to emit a stream of pulses such that the phase of each pulse in the stream of pulses is randomised, and an optical pulse combiner, the optical pulse combiner being configured to receive streams of pulses from the output of each gain-switched laser, combine the streams of pulses with one another into a combined stream of pulses and direct the combined stream of pulses into at least one output of the optical pulse combiner, the at least one output of the optical pulse combiner being the output of the source of phase randomised pulses of light; wherein the source of phase randomised pulses of light is configured such that the streams of pulses of light emitted by the plurality of gain-switched lasers are temporally offset relative to one another, a phase measurement element, the phase measurement element being configured to receive the combined stream of pulses from the output of the source of phase randomised pulses of light; and an optical detector, the optical detector being optically coupled to the phase measurement element.

Device and method for detecting wavefront error by modal-based optimization phase retrieval using extended Nijboer-Zernike theory

The disclosure provides a device for detecting a wavefront error by modal-based optimization phase retrieval using an extended Nijboer-Zernike (ENZ) theory. The detection device includes a point light source (1), a half mirror (2), a lens (3) to be tested, a plane mirror (4) and an image sensor (5). The wavefront error of the component under test is characterized by using a Zernike polynomial, and a Zernike polynomial coefficient is solved based on an ENZ diffraction theory. The present disclosure realizes the one-time full-aperture measurement on the wavefront error of a large-aperture optical component, and can use a partially overexposed image to achieve accurate wavefront error retrieval. Meanwhile, the present disclosure overcomes the contradiction between underexposure and high signal-to-noise ratio (SNR) caused by a limited dynamic range when the image sensor (5) acquires an image. The detection device is simple and does not have high requirements for the experimental environment.

Device and method for detecting wavefront error by modal-based optimization phase retrieval using extended Nijboer-Zernike theory

The disclosure provides a device for detecting a wavefront error by modal-based optimization phase retrieval using an extended Nijboer-Zernike (ENZ) theory. The detection device includes a point light source (1), a half mirror (2), a lens (3) to be tested, a plane mirror (4) and an image sensor (5). The wavefront error of the component under test is characterized by using a Zernike polynomial, and a Zernike polynomial coefficient is solved based on an ENZ diffraction theory. The present disclosure realizes the one-time full-aperture measurement on the wavefront error of a large-aperture optical component, and can use a partially overexposed image to achieve accurate wavefront error retrieval. Meanwhile, the present disclosure overcomes the contradiction between underexposure and high signal-to-noise ratio (SNR) caused by a limited dynamic range when the image sensor (5) acquires an image. The detection device is simple and does not have high requirements for the experimental environment.

REFLECTIVE HOLOGRAPHIC PHASE MASKS
20230236494 · 2023-07-27 ·

A phase transformation device may include a solid photosensitive material having a planar input facet and one or more reflective holographic phase masks (RHPMs) within a volume of the solid photosensitive material, where a particular one of the one or more RHPMs is formed as a periodic refractive index variation of the photosensitive material along a particular grating vector and further with a particular non-planar lateral phase profile, where at least one of a period of the refractive index variation along the grating vector or an orientation of the grating vector for each of the one or more RHPMs are arranged to reflect via Bragg diffraction light incident on the input facet that satisfies a Bragg condition, and where a phase distribution of the reflected light from a particular one of the one or more RHPMs is modified by the associated non-planar lateral phase profile.