Abstract: The invention relates to a method for determination of ambient mineral dust concentration based on optical absorption of particles concentrated by a virtual impactor as well as a device performing the said method. The method comprises the following steps: Sampling air samples with particle size smaller than 1 ?m (PM1) and sampling air samples with particle size up to 10 ?m; Concentrating the samples with particle sizes up to 10 ?m with a virtual impactor; Measuring optical absorption of collected samples at least one wavelength from UV to IR spectre, preferably from 370 to 950 nm, most preferably at 370 nm; Subtracting the absorption of the samples with particle size smaller than 1 ?m from the absorption of the sample concentrated by the virtual impactor.

Abstract: The present invention belongs to the field of systems adapted for detection and quantification of carbonaceous aerosol. It relates to an improved heating chamber for a device for measuring carbonaceous aerosol, the chamber comprising at least: an upper part and a lower part with a ring for closing and holes for pins through which heaters receive the voltage needed for heating; an inlet for leading the sampled air to a filter and a system of valves, which regulates the sampled air flow and air flow during the analysis; two heaters encasing the filter, each heater comprising at least a housing and a heating wire, wherein the first heater is installed in the upper part and the second heater is installed in the lower part, wherein the distance of the heaters from the filter is from 1 to 10 mm, and wherein the heaters are controlled with electronics; and an outlet for leading the created CO2 towards a CO2 detector.

Abstract: The invention relates to a method for determination of ambient mineral dust concentration based on optical absorption of particles concentrated by a virtual impactor as well as a device performing the said method. The method comprises the following steps: Sampling air samples with particle size smaller than 1 ?m (PM1) and sampling air samples with particle size up to 10 ?m; Concentrating the samples with particle sizes up to 10 ?m with a virtual impactor; Measuring optical absorption of collected samples at least one wavelength from UV to IR spectre, preferably from 370 to 950 nm, most preferably at 370 nm; Subtracting the absorption of the samples with particle size smaller than 1 ?m from the absorption of the sample concentrated by the virtual impactor.

Abstract: A photo-thermal interferometer for measuring the light absorption of an aerosol or gas comprises a first laser source emitting a laser beam and a beam splitter adapted to divide the laser beam into a probe beam and a reference beam. The interferometer further comprises first optical elements which are adapted to direct the probe beam such that it passes through the aerosol and interferes with the reference beam thereafter thereby causing interference patterns. A detector detects the interference patterns. The interferometer further comprises a second laser source configured to emit a pump beam for transferring energy to the aerosol. Second optical elements are adapted to direct the pump beam such that it overlaps with the probe beam at least partially in the aerosol or gas. At least one of the second optical elements modifying the pump beam is an axicon.

Abstract: A photo-thermal interferometer for measuring the light absorption of an aerosol or gas comprises a first laser source emitting a laser beam and a beam splitter adapted to divide the laser beam into a probe beam and a reference beam. The interferometer further comprises first optical elements which are adapted to direct the probe beam such that it passes through the aerosol and interferes with the reference beam thereafter thereby causing interference patterns. A detector detects the interference patterns. The interferometer further comprises a second laser source configured to emit a pump beam for transferring energy to the aerosol. Second optical elements are adapted to direct the pump beam such that it overlaps with the probe beam at least partially in the aerosol or gas. At least one of the second optical elements modifying the pump beam is an axicon.

Abstract: An apparatus and method are presented for the analysis of materials. The apparatus includes two or more similar analyzers, with the output of the analyzers combined to provide improved measurements. The apparatus may be, for example, a differential photometric analyzer, such as the AETHALOMETER®. The apparatus includes a processor programmed to accept an instrument constant determined at low filter loadings and use the constant to compensate for non-linear instrument responses. A method is also presented for conditioning filters before use.

Abstract: A method is provided for diagnosing the operation of a photometric particle analyzer. The method may determine when the operation is degraded from normal operating conditions, automatically, and the result displayed locally as well as being transmitted to a remote observer. The present invention may be used by optical photometric particle analyzers, or by analyzers that measure other properties of particles collected on filters.

Abstract: An apparatus and method are presented for the analysis of materials. The apparatus includes two or more similar analyzers, with the output of the analyzers combined to provide improved measurements. The apparatus may be, for example, a differential photometric analyzer, such as the AETHALOMETER®. The apparatus includes a processor programmed to accept an instrument constant determined at low filter loadings and use the constant to compensate for non-linear instrument responses. A method is also presented for conditioning filters before use.

Abstract: An apparatus and method are presented for the analysis of materials. The apparatus includes two or more similar analyzers, with the output of the analyzers combined to provide improved measurements. The apparatus may be, for example, a differential photometric analyzer, such as the AETHALOMETER®. The apparatus includes a processor programmed to accept an instrument constant determined at low filter loadings and use the constant to compensate for non-linear instrument responses. A method is also presented for conditioning filters before use.

Abstract: A method is provided for diagnosing the operation of a photometric particle analyzer. The method may determine when the operation is degraded from normal operating conditions, automatically, and the result displayed locally as well as being transmitted to a remote observer. The present invention may be used by optical photometric particle analyzers, or by analyzers that measure other properties of particles collected on filters.

Abstract: A method is provided for diagnosing the operation of a photometric particle analyzer. The method may determine when the operation is degraded from normal operating conditions, automatically, and the result displayed locally as well as being transmitted to a remote observer. The present invention may be used by optical photometric particle analyzers, or by analyzers that measure other properties of particles collected on filters.

Abstract: A method is provided for diagnosing the operation of a photometric particle analyzer. The method may determine when the operation is degraded from normal operating conditions, automatically, and the result displayed locally as well as being transmitted to a remote observer. The present invention may be used by optical photometric particle analyzers, or by analyzers that measure other properties of particles collected on filters.

Abstract: A method is provided for diagnosing the operation of a photometric particle analyzer. The method may determine when the operation is degraded from normal operating conditions, automatically, and the result displayed locally as well as being transmitted to a remote observer. The present invention may be used by optical photometric particle analyzers, or by analyzers that measure other properties of particles collected on filters.

Abstract: The light source 1 in the slit lamp (FIG. 1) according to present invention is a white light emitting diode (LED) controlled by a control circuit 8. The patient's eye is illuminated by an illuminating slit produced as image 7 of the slit 3 by means of Koehler illumination technique. This means that the phosphorescent surface of the LED is projected through the condenser optics 2 onto the rear objective 4 that makes an image of the slit 3 through a prism or a mirror 6 onto the eye. In this way an evenly illuminated image 7 of the slit 3 is formed on the inspected eye. The control circuit 8 ensures a correct ratio between the voltage across the LED and the current flowing through the LED and enables changing of the emitted light intensity. The color of the light does not vary with the intensity of the light. In an embodiment of the invention, the light source of the slit lamp is a LED emitting simultaneously a red, a green, and a blue light.