Abstract: A microfluidic device includes an upstream liquid handling structure to hold a first volume of liquid, a downstream liquid handling structure to hold a second volume of liquid smaller than the first volume and including a vent port. The upstream liquid handling structure is connected to a detection chamber, for supplying liquid to the detection chamber and the detection chamber is connected to the downstream liquid handling structure, for supplying liquid to the downstream liquid handling structure. The downstream liquid handling structure facilitates flow of an aqueous liquid through the detection chamber and into the downstream liquid handling structure by capillary action. The downstream liquid handling structure includes a flow-halting feature to halt the flow of the liquid by capillary action when the downstream liquid handling structure has filled with the second volume of liquid.

Abstract: A microfluidic liquid handling device is configured for rotation about an axis of rotation to drive liquid flow within the device. The device can include an upstream liquid handling structure, a metering structure and an overflow region. The metering structure is configured to receive liquid from the upstream liquid handling structure. The overflow region is separated from the metering structure by a wall. The wall has a first surface portion on the side of the overflow region which has an extent in a direction perpendicular to the direction of action of the centrifugal force, in a substantially tangential or circumferential direction, relative to the axis of rotation. The first surface portion faces radially outwards. Advantageously, the structure of the wall facilitates accurate metering.

Abstract: A method and system for capturing images of a liquid sample flowing through a field of view of an imaging device that can include stepping a focus mechanism of the imaging device through a plurality of focus values and capturing a plurality of images of the sample at each of the plurality of focus values as the sample flows through the field of view of the imaging device. In this way, image capture can proceed before a focus value has been determined and capture images that are in focus can be used for further processing subsequently.

Abstract: A method and system for capturing images of a liquid sample flowing through a field of view of an imaging device that can include stepping a focus mechanism of the imaging device through a plurality of focus values and capturing a plurality of images of the sample at each of the plurality of focus values as the sample flows through the field of view of the imaging device. In this way, image capture can proceed before a focus value has been determined and capture images that are in focus can be used for further processing subsequently.

Abstract: A method and system for capturing images of a liquid sample flowing through a field of view of an imaging device that can include stepping a focus mechanism of the imaging device through a plurality of focus values and capturing a plurality of images of the sample at each of the plurality of focus values as the sample flows through the field of view of the imaging device. In this way, image capture can proceed before a focus value has been determined and capture images that are in focus can be used for further processing subsequently.

Abstract: A method and system for capturing images of a liquid sample during flow is disclosed. One approach to obtaining images of the sample which are in focus is to carry out a focusing algorithm in order to focus an imaging device on the sample once the sample has started flowing. However, this typically takes dozens of seconds or even minutes. There is provided a method of capturing images of a liquid sample flowing through a field of view of an imaging device that comprises stepping a focus mechanism of the imaging device through a plurality of focus values and capturing a plurality of images of the sample at each of the plurality of focus values as the sample flows through the field of view of the imaging device. In this way, image capture can proceed before a focus value has been determined and capture images that are in focus can be used for further processing subsequently.