The invention relates to a counting chamber for a microscope, adjustable in height. The method measures a cell count at two different chamber heights and deduces the concentration of particles without an exact calibration of the absolute height, as the height difference gives a measurement of the missing volume and therefore an estimate of the particle concentration.

Systems and methods for verifying that light absorption is caused by a targeted gaseous chemical compound. A first transmittance of light, either generated at, or filtered to, a first wavelength range and a second transmittance of light, either generated at, or filtered to, a second wavelength range are measured by first and second photon detectors. A ratio of the first and second measured transmittance is determined and that ratio is compared to a transmittance ratio associated with a targeted gaseous chemical compound to verify that the light absorption is caused by the targeted gaseous chemical compound.

This disclosure is directed to exemplary embodiments of systems, methods, techniques, processes, products and product components that can facilitate users making improved absorbance or fluorescence measurements in the field of spectroscopy with reduced (minimal) sample waste, and increased throughput, particularly in the study of biological sciences. A method and device for photometric measurement of liquids. The method includes the steps of: The method includes the steps of; providing a pipette tip, the pipette tip being made of an optically clear body having an outer wall and an inner wall, the inner wall defining an inner space for receiving a liquid sample, the inner space providing a cross-sectional path length for light; positioning the pipette tip between a light source and a light collector; measuring light transmission through the liquid sample; adjusting the inner space of the pipette tip to change the cross-sectional length, and measuring light transmission through the liquid sample. This can be accomplished by moving the light source from a first position to at least a second position to provide a plurality of cross-sectional path lengths through the liquid sample or by moving the pipette tip from a first position to at least a second position to provide a plurality of cross-sectional path lengths through the liquid sample.

This disclosure is directed to exemplary embodiments of systems, methods, techniques, processes, products and product components that can facilitate users making improved absorbance or fluorescence measurements in the field of spectroscopy with reduced (minimal) sample waste, and increased throughput, particularly in the study of biological sciences. A method and device for photometric measurement of liquids. The method includes the steps of: The method includes the steps of: providing a pipette tip, the pipette tip being made of an optically clear body having an outer wall and an inner wall, the inner wall defining an inner space for receiving a liquid sample, the inner space providing a cross-sectional path length for light; positioning the pipette tip between a light source and a light collector; measuring light transmission through the liquid sample; adjusting the inner space of the pipette tip to change the cross-sectional length, and measuring light transmission through the liquid sample. This can be accomplished by moving the light source from a first position to at least a second position to provide a plurality of cross-sectional path lengths through the liquid sample or by moving the pipette tip from a first position to at least a second position to provide a plurality of cross-sectional path lengths through the liquid sample.

A device (1) for determining the concentration of a gas component is configured with a radiation source (30) for emitting (31) a light radiation or heat radiation in an infrared wavelength range. A detector array (40) has at least two detector elements (50, 60), configured to detect the radiation generated by the radiation source (30), in an angular arrangement (52, 62) and with filter elements (51, 61). At least one of the two detector elements (50, 60) is oriented in an angular arrangement (52, 62) in relation to a vertical axis (32), so that a range of overlap (65) is obtained due to the angular arrangements (52, 62). The range of overlap (65) causes attenuations in the propagation of light, which attenuations may be due, for example, to gas molecules or moisture (400), affect both detector elements (50, 60) and are thus compensated concerning the concentration determination.

The present invention relates to a method for analyzing samples comprising spermatozoa, said method comprising the use of a flow-through counting compartment, wherein the time period between the end of loading and closing is carried out in a controlled and specified time period. The present invention further relates to a counting compartment or chamber suitable for said method and to a counting device comprising said counting compartment.

Apparatus and methods are described for determining a property of a biological sample. A sample carrier (22) includes one or more sample chambers (40) that define at least a first region (42) and a second region (44), the height of the one or more sample chambers varying between the first and second regions in a predefined manner. A computer processor (28) receives data relating to a first optical measurement that is performed upon a portion of the sample that is disposed within the first region, receives data relating to a second optical measurement that is performed upon a portion of the sample that is disposed within the second region, and determines the property of the sample by using a relationship between the first optical measurement, the second optical measurement, and the predefined variation in height between the regions. Other applications are also described.

The present disclosure relates to a substrate defect measuring apparatus for detecting defects inside a substrate by photoluminescence and detecting defects outside the substrate by using the scattering of incident light for generating photoluminescence, and provides an apparatus for constituting an optical system in order to measure scattered and/or reflected light together in a procedure of measuring the photoluminescence, thereby shortening a measurement time.

Embodiments create an arrangement and a method for analyzing a fluid. The arrangement (10) for analyzing a fluid comprises beam splitter and mixer optics (12) configured to spatially mix an optical signal and split the same into at least two spatial sub-beams and a flow cell (14) configured to spectrally influence at least the two spatial sub-beams (15a; 15b) by means of a probe of the fluid. The arrangement further comprises a measurement system (16) configured to measure the at least two spatially separated sub-beams (15a; 15b).

The present invention relates to a method for analyzing samples comprising spermatozoa, said method comprising the use of a flow-through counting compartment, wherein the time period between the end of loading and closing is carried out in a controlled and specified time period. The present invention further relates to a counting compartment or chamber suitable for said method and to a counting device comprising said counting compartment.