System and method for determining a viscoelastic modulus of a sample with the use of optical data and an average size of light-scattering particles, of such sample, that has been derived from the optical data in reliance of angular dependence of a radiant flux profile determined from laser speckles formed by the sample and, in required, on a refractive index mismatch between light-scattering particles and sample medium hosting such particles. The determination is optionally carried out by taking into account at least one of absorption coefficient and reduced scattering coefficient of the sample, which are also determined from the same optical data. Laser speckle may be formed for different combinations of polarization states of sample-illuminating light and detected light and/or different wavelengths to account for polydisperse nature of the sample.

Some implementations of the present disclosure provide a method that includes: irradiating a target surface with a process beam during a drilling process; in response to irradiating with the process beam, receiving a signal beam that contains light scattered from the target surface as well as light radiating from the target surface; splitting the signal beam into a first portion on a polarization arm and a second portion on a non-polarization arm; performing, on the polarization arm, a first plurality of polarization-dependent intensity and spectrum measurements of the first portion; performing, on the non-polarization arm, a second plurality of intensity and spectrum measurements of the second portion; and based on applying one or more machine learning techniques to at least portions of (i) the first plurality of polarization-dependent intensity and spectrum measurements, and (ii) the second plurality of intensity and spectrum measurements, determining a classification of the target surface.

A method for detecting at least one property of a plant product, the method including: directing source light including ultraviolet (UV) light at UV wavelengths and polarized visible and/or near-infrared (VIS/NIR) light at VIS/NIR wavelengths onto a region of the plant product; blocking the polarized VIS/NIR light of the source light, and blocking polarized specular reflection from the region of the plant product, from being transmitted to a visible and/or near-infrared (VIS/NIR) spectrometer; and transmitting a portion of emitted light caused by fluorescence and/or diffuse reflection from the region of the plant product to the visible and/or near-infrared (VIS/NIR) spectrometer.

An apparatus for acquiring a wavelength and polarization state of light for imaging a structure at least partially obscured, in a visible wavelength range, by a liquid, is provided by the present disclosure.

A method and system for high-speed 2 multi-point scatterometry is disclosed. The method includes directing a laser beam from a laser light source to a collimation optical system that collimates the laser beam to a collimated laser beam; adjusting a polarization of the collimated laser beam using a polarization control optics; directing the collimated laser beam that is polarized by a first optical system to illuminate a focal area on a sample surface; receiving reflected light from the focus of the laser light source at the sample surface by a second optical system; detecting the reflected light by a detector system to produce detection signals; and processing the detection signals to measure parameters of the sample surface.

A system includes a radiation source that generates radiation having at least one wavelength from 0.1 to 100 nm. One or more rotating elements change polarization of the radiation and/or relative phase between two polarizations of the radiation. A stage is configured to hold a workpiece in a path of the radiation. At least one detector receives spectral reflection and scattering radiation from the workpiece.

A method and system for high-speed 2 multi-point scatterometry is disclosed. The method includes directing a laser beam from a laser light source to a collimation optical system that collimates the laser beam to a collimated laser beam; adjusting a polarization of the collimated laser beam using a polarization control optics; directing the collimated laser beam that is polarized by a first optical system to illuminate a focal area on a sample surface; receiving reflected light from the focus of the laser light source at the sample surface by a second optical system; detecting the reflected light by a detector system to produce detection signals; and processing the detection signals to measure parameters of the sample surface.

A method for characterizing a photonic integrated circuit comprising includes coupling an evanescent field into a scattering element adjacent to a guiding layer of the photonic integrated circuit. The evanescent field is of an optical mode of light propagating in the guiding layer, and has an in-medium wavelength in the guiding layer. A maximum spatial dimension of the scattering element is less than the in-medium wavelength. The method includes scattering, with the scattering element, the coupled evanescent field as a reference scattered-signal. The method also includes detecting one of the reference scattered-signal and a signal derived therefrom.

Included are a light-emitting unit that irradiates a specimen having a film-like shape and having optical transparency with the inspection light, a scattered light detection unit that detects scattered light from the specimen, a diffracted light detection unit that detects diffracted light from the specimen, and a signal processing unit that determines the presence of a contaminant attached to the specimen and the presence of a pinhole formed in the specimen, on the basis of a scattered light intensity signal from the scattered light detection unit and a diffracted light intensity signal from the diffracted light detection unit.

A system and method for a photoelectric smoke detector using polarized light is disclosed. The system may include a light source to emit a beam of light at a polarity of interest. The system may also include a light sensor to detect a reflection of the beam of light at the polarity of interest. The system may additionally include a control circuit communicatively coupled to the light sensor. The control circuit may be to detect a presence of smoke and raise a smoke alarm signal. The polarity of interest may be based on an angle of incidence between the light source and the light sensor.