Abstract: A sensor is provided for detecting and characterizing particles in a fluid. The sensor has a microfluidic channel for receiving the fluid sample, an acoustic transducer module configured to generate a standing wave for concentrating the particles in a region of the microfluidic channel; an optical detection module configured to detect optical signals scattered by the particles upon illuminating the region of the fluid sample with a light source; and a data processing module configured to characterize the particles of the fluid sample based on the optical signals using a classifier.

Abstract: A microfluidic device and method is provided for concentrating particles in a fluid sample. The microfluidic device has a chamber, wherein the chamber has a filtering unit defining a first compartment and a second compartment, the first compartment being in fluid communication with the second compartment and being for receiving a fluid sample containing particles, the filtering unit being configured to selectively retain particles of the fluid sample based on a size of the particles, at a sub-region of the first compartment as the fluid sample flows from the first compartment to the second compartment; and an acoustic transducer configured to generate acoustic waves in the sub-region to disperse the particles.

Abstract: A sensor is provided for detecting and characterizing particles in a fluid. The sensor has a microfluidic channel for receiving the fluid sample, an acoustic transducer module configured to generate a standing wave for concentrating the particles in a region of the microfluidic channel; an optical detection module configured to detect optical signals scattered by the particles upon illuminating the region of the fluid sample with a light source; and a data processing module configured to characterize the particles of the fluid sample based on the optical signals using a classifier.

Abstract: An immersion refractometer includes a microchamber having an inlet and an outlet for allowing a sample containing microorganism particles to flow therethrough, wherein the microchamber comprises at least one trapping site for trapping a microorganism particle in each respective trapping site, and a micromixer for mixing a plurality of liquids to form an external medium, wherein the micromixer and the microchamber are in fluid communication to introduce the external medium into the microchamber. Use of the present immersion refractometer in a method of identifying microorganism particles contained in a sample is also provided.

Abstract: An immersion refractometer includes a microchamber having an inlet and an outlet for allowing a sample containing microorganism particles to flow therethrough, wherein the microchamber comprises at least one trapping site for trapping a microorganism particle in each respective trapping site, and a micromixer for mixing a plurality of liquids to form an external medium, wherein the micromixer and the microchamber are in fluid communication to introduce the external medium into the microchamber. Use of the present immersion refractometer in a method of identifying microorganism particles contained in a sample is also provided.

Abstract: An apparatus and method for analyzing biological cells and other particles using an external laser cavity. Microfluidic channels contain and transport biological cells to be analyzed. A laser diode provides light for cell analysis. An external cavity is provided between one surface of the laser diode and a mirror opposite thereto. A microlens set focuses the light on only one cell as it passes through the external cavity. The presence of the cell in the external cavity gives a weak feedback toward the laser diode. The emission frequency and the output power of the laser are both functions of the length of the external cavity. Therefore, the variation of cavity length can be deduced from these parameters, where the variation is caused by changing the refractive index or size of the cell in the cavity.

Abstract: Methods and apparatuses for sensing and adjusting lateral motion in a comb drive actuated MEMS device are provided. If lateral motion is sensed by a lateral motion sensor coupled to the comb drive actuated MEMS device, and the lateral motion is greater than a reference value, a feedback controller adjusts the lateral motion by providing a drive signal to a comb drive electrode of a comb drive actuator.

Abstract: A microfluidic system for separating, purifying and counting cell sub-populations, utilising steering of liquid flows in microfluidic channels in a cell focusing region (first dotted circle area); having the integration of the optical detection mechanism and a microchannel structure made from moulding. A master is photolithographically patterned on a soft PDMS silicon or polymer material. After being moulded and peeled off the master, the micro-channel structure is sealed on a hard substrate with openings punched through for wells (14, 12, 36, 38, 40). An optical detection region (20) discriminates different types of cells that have been formed into a single flow (30). Electromagnetic fields are used to steer (32) the flows of cells according to the signals from the optical detection region into branch channels leading to the punched wells for separate collection. The system can have parallel systems that increase throughput or cascade systems to provide several analysis steps.

Abstract: Methods and apparatuses for sensing and adjusting lateral motion in a comb drive actuated MEMS device are provided. If lateral motion is sensed by a lateral motion sensor coupled to the comb drive actuated MEMS device, and the lateral motion is greater than a reference value, a feedback controller adjusts the lateral motion by providing a drive signal to a comb drive electrode of a comb drive actuator.

Abstract: The invention features the drawbridge assembly and its applications in optical switches, optical crossconnects, optical add/drop multiplexers and variable optical attenuators. In optical switches and optical crossconnects, an array of the drawbridge assemblies can be used to redirect the multiple input lights to multiple outputs. In add/drop multiplexers, the drawbridge assemblies can select the light channels to be added and dropped. In the attenuator embodiment, a vertical mirror is inserted into two fibers, the first one as the input and the second one as output. The drawbridge assembly controls the position of the vertical mirror for blocking a certain portion of the light and enabling the attenuation. The continuous change of the mirror position results in variable attenuation. A series of VOA form a multi-channel VOA system on a single substrate.

Abstract: The invention features the drawbridge assembly and its applications in optical switches, optical crossconnects, optical add/drop multiplexers and variable optical attenuators. In optical switches and optical crossconnects, an array of the drawbridge assemblies can be used to redirect the multiple input lights to multiple outputs. In add/drop multiplexers, the drawbridge assemblies can select the light channels to be added and dropped. In the attenuator embodiment, a vertical mirror is inserted into two fibers, the first one as the input and the second one as output. The drawbridge assembly controls the position of the vertical mirror for blocking a certain portion of the light and enabling the attenuation. The continuous change of the mirror position results in variable attenuation. A series of VOA form a multi-channel VOA system on a single substrate.