This disclosure relates generally to methods and systems for designing an optimal dual-band metamaterial polarization converter for refractive index sensing applications. Most of the existing techniques for designing the metamaterial-based polarization converters operating at very high frequency range limits the sensing performance and increases fabrication complexity. In the design of the optimal dual-band metamaterial polarization converter, first a circular split-ring resonator (SRR) as a unit cell is designed. Secondly, the two capacitive gaps of the top layer, are aligned at 180 degrees with respect to each other and at 45 degrees with respect to X-axis and Y-axis. Lastly, step-by-step tuning the one or more key design parameters of the SRR, is performed until an optimum frequency response is obtained, to obtain the optimal dual-band metamaterial polarization converter.

A process for manufacturing an optical system includes forming a first hydrophobic surface at a semiconductor substrate, providing a first drop of transparent material having a first shape on the first hydrophobic surface, and allowing the first drop to harden to form a first optical element having the first shape. The optical system may be a particle detector, and the process may optionally further include forming a light source at the semiconductor substrate configured to generate a light beam that passes through the first optical element and a cavity to a photodetector.

The invention relates to a method for determining the average radius of gyration (r.sub.g) of particles with a size of 1 m in a suspension, and to a device for carrying out the method according to the invention. The method is based on the scattering of linearly polarised electromagnetic radiation on nanoparticles, which, suspended in a solution, are moved through a through-flow cell. The irradiation is carried out perpendicular to the movement direction, wherein the scattering intensity is measured via at least four detectors that are arranged in a defined plane at defined angles. Alternatively, at least one mirror can be used in the position of at least one of the detectors, which deflects the radiation to at least one detector. Based on the scattering intensities, both the average radius of gyration (r.sub.g) of the particles as well as the concentration thereof in the suspension can be determined.

A measurement apparatus according to the present disclosure is a measurement apparatus capable of measuring particles in a fluid and comprises: a flow path device including a first flow path with translucency through which a first fluid including the particles passes and a second flow path with translucency through which a second fluid which does not include the particles passes; an optical sensor facing the flow path device, irradiating each of the first flow path and the second flow path with light, and receiving light passing through each of the first flow path and the second flow path; and a controller measuring the particles by comparing an intensity of light passing through the first flow path and an intensity of light passing through the second flow path, each of which is obtained by the optical sensor.

An apparatus for microfluidic flow cytometry analysis of a particulate containing fluid An apparatus for microfluidic flow cytometry analysis of a particulate containing fluid comprises a hydrodynamic focussing apparatus for providing a focused stream of particulate containing fluid; and a microfluidic chip. The chip has a plurality of layers and comprises a microfluidic channel that extends through the chip substantially orthogonal to a plane of the layers of the chip, and is in fluid communication with the hydrodynamic focusing apparatus for receipt of a focused steam of particulate containing fluid. The chip also comprises a detection zone comprising at least one pair of electrodes in electrical communication with the microfluidic channel. At least one pair of electrodes comprise an excitation electrode coupled to an AC signal source and a detection electrode configured to detect AC impedance changes in the microfluidic channel between the electrodes resulting from particles passing between the electrodes in the microfluidic channel. Methods of sorting mammalian sperm cells according to sex is also described.

A system for modeling a collisional plasma particles distribution is provided. The system includes an input beam generator configured to generate an input beam having a first set of values of a parameter modelling an initial distribution of particles in a collisional plasma, a non-linear optical medium configured to receive the input beam and produce a complex response function in response to receiving the input beam, an output detector configured to detect a second set of values of the parameter responsive to propagation of the input beam through the non-linear medium to the output detector, a feedback module configured to modify one or more properties of the non-linear optical medium, and a controller configured to select the first set of values, receive the second set of values, and determine, based on the first set and the second set of values, a final distribution of the particles in the collisional plasma.

A method for determining a parameter of a particle present in a sample, the method comprising the following steps: a) illuminating the sample with the light source, the light source emitting an incident light wave that propagates along a propagation axis; b) acquiring an image of the sample with the image sensor, the image sensor being exposed to an exposure light wave; c) determining a position of the particle in the detection plane; d) on the basis of the acquired image, applying a propagation operator, for a plurality of distances from a detection plane, so as to estimate, at each distance, a complex amplitude of the exposure light wave; e) on the basis of the complex amplitude estimated, at various distances, obtaining a profile representing a variation of the complex amplitude of the exposure light wave along an axis parallel to the propagation axis and passing through the position of the particle.

The particle may associated with a set of parameters, comprising at least a size of the particle and a refractive index of the particle.

A system for modeling a collisional plasma particles distribution is provided. The system includes an input beam generator configured to generate an input beam having a first set of values of a parameter modelling an initial distribution of particles in a collisional plasma, a non-linear optical medium configured to receive the input beam and produce a complex response function in response to receiving the input beam, an output detector configured to detect a second set of values of the parameter responsive to propagation of the input beam through the non-linear medium to the output detector, a feedback module configured to modify one or more properties of the non-linear optical medium, and a controller configured to select the first set of values, receive the second set of values, and determine, based on the first set and the second set of values, a final distribution of the particles in the collisional plasma.

The present description provides, in some embodiments, an apparatus for mixing a fluid in a circuit having an inlet channel defining a flow path for a fluid including particulate matter, a first reagent channel in fluid communication with the inlet channel and defining a first reagent flow path for a first reagent, the inlet channel and first reagent channel configured to shear the fluid entering the first reagent channel from the inlet channel at a first junction, a shearing channel in fluid communication with the inlet channel and first reagent channel at the first junction, and a diffusion channel in fluid communication with the shearing channel at a second junction, the sheared fluid collectable into the diffusion channel such that the fluid is compressed at least in part by the first reagent to have a thickness close to a diameter of the particulate matter in the fluid.

A particle detector including at least one channel intended to receive at least one fluid comprising particles and configured to receive at least one light beam emitted by a light source. The particle detector further including at least one photodetector network configured such that at least some photodetectors receive light beams emitted by the source and scattered by the particles present in the channel. The detector further comprises at least one optical system, each optical system s associated with a photodetector network and has at least one image focal plane and an optical axis. The detector is configured such that the image focal plane of the optical system is optically coupled to the photodetector network.