An optical microcavity device (10), an alignment structure for an optical device, and a method for aligning an optical device are disclosed. The optical microcavity device (10) comprises: a first optical reflector (20); a second optical reflector (30) opposed to the first optical reflector (20) along an optical axis (40), the first and second optical reflectors (20, 30) being spaced from each other forming an open space therebetween; wherein the first optical reflector (20) comprises a first cavity reflector (22) and a first alignment reflector (24), wherein the second optical reflector (30) comprises a second cavity reflector (32) and a second alignment reflector (34), the second cavity reflector (32) comprising a recess to provide an optical microcavity between the first and second cavity reflectors (20, 30), the optical microcavity having an optical cavity length of at most 50 μm and/or an optical mode volume of 100 μm3 or less; an EM radiation source (50) configured for illuminating the optical microcavity with EM radiation (52) to cause multi-pass interference within the optical microcavity; and an alignment system configured to: illuminate the first and second alignment reflectors (24, 34) of the first and second optical reflectors (20, 30) to generate an optical interference pattern (74); detect the optical interference pattern (74); and determine a relative orientation and/or separation of the first and second optical reflectors (20, 30) based on the detected optical interference pattern (74); the alignment system further comprising an actuator system (100, 102) configured to move the first and second optical reflectors (20, 30) relative to each other to change the relative orientation and/or separation of the first and second optical reflectors (20, 30) based on the determined relative orientation and/or separation. At least one of the first and second alignment reflectors (20, 30) may comprise an alignment structure comprising at least two reflective surface portions having different angular orientations.

A particle counter for chemical solution in this disclosure uses a flow cell through which a chemical solution including particles flows, a laser light, and a light-receiving element array. Scattered light from the particles passing through a detection region on an optical path of the laser light in the flow cell is condensed to the light-receiving element array. The laser light in the center of the detection region has an energy density of 3×10.sup.8 mW/cm.sup.2 or more. Each of plural light-receiving elements (a) is larger in length and width than a spot diameter of the scattered light, and (b) receives the scattered light from a region with a size of 760 μm.sup.2 or less included in the detection region. The signal processing unit counts the particles passing through the detection region by use of a threshold corresponding to the smallest measurable particle size of 0.03 μm.

A measuring chamber device for an optically operating sensor for determining a concentration of a substance that is contained in tissue fluid of a mammal. The measuring chamber device has a measuring chamber filled with a liquid measuring medium and a wall with better diffusion permeability for the substance than for other constituents of the tissue fluid. A transmitter device for emitting optical radiation into the measuring chamber, and a receiver device for receiving optical radiation that has passed through the measuring chamber are also provided.

Provided are a protein-matrix microlens array diffraction device and a preparation method thereof. The protein-matrix microlens array diffraction device includes a matrix of a protein crystal. A largest side of the protein crystal has a length of 100 to 500 μm, a surface of the protein crystal where the largest side is located is processed to have an array of microlens-like protrusions, a distance p between two adjacent microlens-like protrusions of the array of microlens-like protrusions is in a range of 10 to 100 μm, a diameter d of the microlens-like protrusion is in a range of 2 to 10 μm, and a height h of the microlens-like protrusion is in a range of 0.05 to 2 μm.

Provided are a protein-matrix microlens array diffraction device and a preparation method thereof. The protein-matrix microlens array diffraction device includes a matrix of a protein crystal. A largest side of the protein crystal has a length of 100 to 500 μm, a surface of the protein crystal where the largest side is located is processed to have an array of microlens-like protrusions, a distance p between two adjacent microlens-like protrusions of the array of microlens-like protrusions is in a range of 10 to 100 μm, a diameter d of the microlens-like protrusion is in a range of 2 to 10 μm, and a height h of the microlens-like protrusion is in a range of 0.05 to 2 μm.

A sanitary in-line sight glass assembly is provided having separate first and second hollow connection bodies and a transparent tube retainable between and within the connection bodies when the connection bodies are secured together in an end-to-end abutting relationship. Gaskets are located within the connection bodies at opposite ends of the transparent tube and a clamp is provided for securing the ends of the connection bodies together such that the gaskets are compressed and form seals. The connection bodies include sidewalls having at least one opening through which the transparent tube is exposed for providing a viewing window into a flow path defined by the assembly. The clamp may be a circumferentially-extending clamp having ends secured together with a winged fastener able to be gripped by the hand of an installer such that the assembly can be assembled and disassembled manually without the use of a tool.

A sanitary in-line sight glass assembly is provided having separate first and second hollow connection bodies and a transparent tube retainable between and within the connection bodies when the connection bodies are secured together in an end-to-end abutting relationship. Gaskets are located within the connection bodies at opposite ends of the transparent tube and a clamp is provided for securing the ends of the connection bodies together such that the gaskets are compressed and form seals. The connection bodies include sidewalls having at least one opening through which the transparent tube is exposed for providing a viewing window into a flow path defined by the assembly. The clamp may be a circumferentially-extending clamp having ends secured together with a winged fastener able to be gripped by the hand of an installer such that the assembly can be assembled and disassembled manually without the use of a tool.

The invention relates to a method of determining a concentration of a substance in a cell suspension, said method comprising the following steps: determining the concentration of the substance by: using the results of absorption measurements performed at n local sample volumes contained at different average chamber heights of a chamber arrangement comprising the cell suspension and local substance concentration in said respective local sample volumes determined based on said respective absorption measurements; using a substance concentration model comprising local substance concentration as a function of chamber height, anddetermining the substance concentration as the infinite chamber height substance concentration using said substance concentration model and the determined local substance concentrations, wherein n is at least 2, such as at least 3, such as at least 4, wherein, optionally, the cell suspension is whole blood and the substance is Hb and wherein the method further comprises determining cRBC based on the determined Hb concentration and a determined Mean Corpuscular Hemoglobin (MCH). The invention also relates to a system for executing the method.

A flow cell includes a housing, a window member, and a pressing member. The housing includes a cell channel in which a sample flows through, has, on at least one end side of the cell channel, an opening communicating with the cell channel, and has a flat surface at an edge of the opening. The window member has a lens portion at a central portion and a peripheral edge portion whose one surface and the other surface are flat. In the window member, one surface of the peripheral edge portion is provided facing the flat surface of the housing so as to seal the opening.

Measuring device (1) for analyzing a respiratory gas flow, comprising at least one measuring unit (4) and a cuvette (5), the cuvette (5) being releasably connected to the measuring unit (4) and being adapted and configured so that a respiratory gas flows through said cuvette, the measuring unit (4) having at least two sensor units (41, 42), at least one sensor unit (41) being configured to determine a respiratory gas flow and at least one sensor unit (42) being configured to determine a CO2 concentration in a respiratory gas, and the cuvette (5) comprising at least two sensor connections (51, 52) for connecting the sensor units (41, 42) for determining at least one respiratory gas flow and at least one CO2 concentration of a respiratory gas.