Various sensors, including particulate matter sensors, are described. One particulate matter sensor includes a self-mixing interferometry sensor and a set of one or more optical elements. The set of one or more optical elements is positioned to receive an optical emission of the self-mixing interferometry sensor, split the optical emission into multiple beams, and direct each beam of the multiple beams in a different direction. The self-mixing interferometry sensor is configured to generate particle speed information for particles passing through respective measurement regions of the multiple beams.

A search device updates positions and momentums of a plurality of virtual particles, for each unit time from an initial time to an end time. The search device, for each unit time, calculates, for each of the particles, a position at a target time of a corresponding particle, calculates, for each of a plurality of nodes, a first accumulative value by cumulatively adding positions at the target time of two or more particles corresponding to outgoing two or more directed edges, calculates, for each of the nodes, a second accumulative value by cumulatively adding positions at the target time of two or more particles corresponding to incoming two or more directed edges, and calculates, for each of the particles, a momentum at the target time of a corresponding particle based on the first accumulative value and the second accumulative value.

An apparatus for measuring black powder dislodgment and entrainment velocities. The apparatus comprises an inlet section including a first gas source having a test gas, a second source having an additional gas, and an inlet pipe coupled to the first and second gas sources, a plenum having an inlet plate coupled to the inlet pipe for receiving the test gas or the additional gas and distributing the received gas into a steady flow, and a plurality of test sections extending from the plenum, each test section including a particle generation spool at which black powder is generated from the test gas via a condensation process, and a filtration spool downstream from the particle generation spool having at least one membrane element for filtering out black powder from the test gas flow and also having pressure gauges from which black powder dislodgment and entrainment velocities can be determined.

A sensor arrangement characterizes particles. The arrangement has an emitter with a laser source that generates a laser beam; a mode converter that generates a field distribution of the laser beam, which at each position has a different combination of a local intensity and a local polarization direction of the laser beam; and focusing optics that focus the field distribution of the laser beam onto at least one measurement region, through which the particles pass, in a focal plane. A receiver is also provided with analyzer optics configured to determine polarization-dependent intensity signals of the field distribution of the laser beam in the at least one measurement region; and an evaluator configured to characterize the particles, including the particle position, the particle velocity, the particle acceleration, or the particle size, using the polarization-dependent intensity signals.

A sperm sorting apparatus and a sperm sorting method are provided. The sperm sorting apparatus includes a medium chamber, a waste chamber and a sorting channel communicated with and extending along a first direction in between. The medium chamber is configured to contain a medium solution. The waste chamber disposed aside the medium chamber is configured to contain a residual solution after sorting. The residual solution includes low motility sperms and/or dead sperms. The sorting channel is configured to be inserted with a sperm sample, such that sperms in the sperm sample are sorted in corresponding to a medium solution flow from the medium chamber. The sorting channel has first and second portions. The first portion is closer to the medium chamber than the second portion. A width of the first portion measured along a second direction is greater than a critical dimension, ranging from 200 μm to 400 μm.

A sensor arrangement characterizes particles. The arrangement has an emitter with a laser source that generates a laser beam; a mode converter that generates a field distribution of the laser beam, which at each position has a different combination of a local intensity and a local polarization direction of the laser beam; and focusing optics that focus the field distribution of the laser beam onto at least one measurement region, through which the particles pass, in a focal plane. A receiver is also provided with analyzer optics configured to determine polarization-dependent intensity signals of the field distribution of the laser beam in the at least one measurement region; and an evaluator configured to characterize the particles, including the particle position, the particle velocity, the particle acceleration, or the particle size, using the polarization-dependent intensity signals.

A method for sorting motile cells includes introducing an initial population of motile cells into an inlet port of a microfluidic channel, the initial population of motile cells having a first average motility; incubating the population of motile cells in the microfluidic channel; and collecting a sorted population of motile cells at an outlet port of the microfluidic channel. The sorted population of motile cells has a second average motility higher than the first average motility.

A system and method for sorting sperm is provided. The system includes a housing and a microfluidic system supported by the housing. The system also includes an inlet providing access to the microfluidic system to deliver sperm to the microfluidic system and an outlet providing access to the microfluidic system to harvest sorted sperm from the microfluidic system. The microfluidic system provides a flow path for sperm from the inlet to the outlet and includes at least one channel extending from the inlet to the outlet to allow sperm delivered to the microfluidic system through the inlet to progress along the flow path toward the outlet. The microfluidic system also includes a filter including a first plurality of micropores arranged in the flow path between the inlet and the outlet to cause sperm traveling along the flow path to move against through the filter and gravity to reach the outlet.

The invention describes a laser sensor module. The laser sensor module comprises at least a first laser (111) being adapted to emit a first measurement beam (111′) and at least a second laser (112) being adapted to emit a second measurement beam (112′). The laser sensor module further comprises an optical device (150) being arranged to redirect the first measurement beam (111′) and the second measurement beam (112′) such that the first measurement beam (111′) and the second measurement beam enclose an angle between 45° and 135°. The laser sensor module comprises one detector (120) being adapted to determine at least a first self-mixing interference signal of a first optical wave within a first laser cavity of the first laser (111) and at least a second self-mixing interference signal of a second optical wave within a second laser cavity of the second laser (112). This configuration enables determination of an average velocity of the particles despite of the fact that it is not possible to determine the components of the velocity vector. The introduced error by means of statistical variations is acceptable because the number of detected particles scales with the cubic root of the particle velocity. The invention further describes a particle sensor (100) comprising such a laser sensor module, a corresponding method and computer program product. The invention enables a simple and low-cost particle sensor (100) for detecting small particles based on laser self-mixing interference.

A system and method for sorting sperm is provided. The system includes a housing and a microfluidic system supported by the housing. The system also includes an inlet providing access to the microfluidic system to deliver sperm to the microfluidic system and an outlet providing access to the microfluidic system to harvest sorted sperm from the microfluidic system. The microfluidic system provides a flow path for sperm from the inlet to the outlet and includes at least one channel extending from the inlet to the outlet to allow sperm delivered to the microfluidic system through the inlet to progress along the flow path toward the outlet. The microfluidic system also includes a filter including a first plurality of micropores arranged in the flow path between the inlet and the outlet to cause sperm traveling along the flow path to move against through the filter and gravity to reach the outlet.