A maintenance method of a gas detecting device includes the following steps: providing the gas detecting device that includes a shell component, a sensing component, a dust blocking element, and a detecting area, the sensing component including a sensor, a reference light source, and a processor, and the dust blocking element including a cover; the reference light source generating a reference beam projecting toward the cover and the detecting area, and the reference beam generating a feedback beam projecting toward the cover and the sensor through being reflected by a part of the shell component positioned at the detecting area; the sensor receiving the feedback beam to generate a measured information; and the processor comparing the measured information to an initial information in the processor, so as to obtain a pollution degree information of the cover.

The disclosure relates to a gas analysis method by Raman spectrometry, the method comprising the steps of generating by a laser source a laser beam sweeping a range of frequencies including a plurality of resonance modes of an optical cavity holding gases to be analyzed; delivering the laser beam into the cavity; extracting from the cavity a feedback beam that is sent adjusted in phase and amplitude to the source; during the frequency range sweeping, detecting light intensity peaks in the laser beam in the cavity, the phase of the feedback beam being adjusted to reduce shape asymmetries of the peaks, the amplitude of the feedback beam being adjusted to reduce intervals of zero intensity between the peaks; and performing a spectral analysis of the light inelastically scattered in the cavity, to determine the composition of the gases to be analyzed.

An optical system may include an objective lens system having a primary optical axis and a relay lens system having a relay optical axis. The relay optical axis may have a first angular offset with respect to the primary optical axis. The objective lens system may be configured to provide light from a light source to the relay lens system and provide light from the relay lens system to an image sensor. The relay lens system may be configured to provide light from the objective lens system to an end face of an optical fiber, where the end face has a second angular offset with respect to a cross-sectional axis of the optical fiber. The relay lens system may provide light reflected from the end face to the objective lens system.

A sensor of the present disclosure includes a sensor housing with a housing window; a sensor unit arranged in the sensor housing suitable for emitting a sensor signal through the housing window and for receiving a detection signal through the housing window (3); a cleaning unit having a cleaning element, a holder and a drive, wherein the cleaning element is attached to the holder such that the cleaning element is suitable for contacting the housing window from the outside, wherein the drive is non-positively connected to the holder and is suitable for moving the cleaning element across the housing window; and a pressing unit which is suitable for exerting an adjustable contact pressure on the cleaning unit so that the cleaning element is pressed against the housing window with the contact pressure.

A vehicle sensor assembly includes an optical sensor surface, at least two transducers arranged to input energy into the optical surface to produce an energy wave through the optical sensor surface and sense an attribute of an energy wave within the optical sensor surface. A controller arranged to drive the at least two transducers to input energy into the optical surface to produce an energy wave within the optical sensor surface to dislodge debris from the optical sensor surface.

The present disclosure relates to an optical sensor having a light source that emits light on a sensor layer, wherein the sensor layer can be brought into contact with a medium, wherein the first sensor layer emits emission light as a function of the incident light and a concentration of a measured value of the medium; a receiver, which receives the emission light; a first light guide, which conducts light from the light source onto a first region of the sensor layer and conducts emission light from the first region of the sensor layer to the receiver; and a second light guide independent of the first light guide which conducts light from the light source onto a second region of the first sensor layer and conducts emission light from the second region of the sensor layer to the receiver.

An apparatus configured to fog test eyewear includes an environmentally controlled chamber, a head form disposed within the chamber, a radiator disposed within the chamber, the radiator connected to a liquid cooling system, and a humidifier device configured to deliver a flow of warm moist air towards the frontal portion of the head form and a surface of the eyewear. A camera is disposed within the head form, the camera aligned with a first opening in a frontal portion of the head form and configured to detect a target image within the chamber while the flow of warm moist air is delivered. A processor is configured to calculate a contrast difference between a background of the target image detected by the camera and resolution bars of the target image detected by the camera, plot a contrast ratio from the calculated contrast difference against a known calibration standard and calculate a performance measure of an anti-fog device of the eyewear.

A laser sensor module measures a particle density of particles with a size of less than 20 μm. The laser sensor module includes: a laser configured to emit a laser beam; a detector; and an optical arrangement. The optical arrangement is configured to focus the laser beam to a focus region. The laser is configured to emit the laser beam through the optical arrangement to the focus region. The optical arrangement has an emission window. The detector is configured to determine an interference signal of an interference of reflected laser light with emitted later light of the laser beam. The laser sensor module is configured to provide an indication signal of a soiling of the emission window based on the interference signal determined during a mechanical excitation of the emission window.

A device is provided for IR-spectroscopy and for determining an impairment of a surface which is exposed to measuring radiation during the IR-spectroscopy. The device includes a radiation source to generate the measuring radiation a detector and a sample receptacle for receiving a sample. The sample receptacle is at least partially delimited by the surface. The detector measures radiation after interaction with the sample. The device is configured to measure an IR-reference spectrum of a reference sample which is received in the sample receptacle, evaluate the reference spectrum, determine an indicator of the impairment, wherein evaluating encompasses an integration of a quantity which is based on the reference spectrum over a predetermined integration spectral range, wherein the indicator is determined dependently on a value of the integration.

Aspects of the present disclosure include methods for detecting events in a flow cytometer. Also provided are methods of detecting cells in a flow cytometer. Other aspects of the present disclosure include methods for determining a level of contamination in a flow cell. Computer-readable media and systems, e.g., for practicing the methods summarized above, are also provided.