Aerosol jet printing is a popular digital fabrication method for flexible and hybrid electronics, but it lacks sophisticated process control architectures that would enable more widespread adoption in manufacturing environments. An optical measurement system can be used to track the aerosol density upstream of the printhead. For example, the measured optical extinction combined with the aerosol flow rate, is directly related to deposition rate and accurately predicts functional properties, for example electrical resistance. This real-time system offers a compelling solution for process drift and batch-to-batch variability, a valuable tool for more fundamental studies of the process science, and a viable technology to support real-time control of aerosol jet printing.

A method for operating a particle sensor. The particle sensor includes a laser module having a laser, and a detector configured to detect thermal radiation, an optical element positioned in the optical path of the laser of the laser module. The optical element is configured to focus laser light emanating from the laser module onto a spot, and the detector is positioned in the particle sensor in such a manner that it detects radiation emanating from the spot. The method includes subjecting the output signals of the detector to filtering, by which output signals generated by particles not sufficiently heated are excluded from further evaluation. A control unit configured to operate the particle sensor is also described.

A method for capturing at least particle compositions (21) in a monitoring region (14) that exhibit a temporally dynamic behaviour with an optical detection apparatus (12), and an optical detection apparatus (12) are described. In the method, during at least one measurement, optical transmission signals (22) are transmitted into the monitoring region (14) and transmission signals (22) that are reflected at particle targets (28) of any particle compositions (21) present in the monitoring region (14) are received as particle reflection signals (30). The presence of dynamic particle compositions (21) is concluded from the particle reflection signals (30). At least two measurements are performed with a temporal distance. A particle target density or a variable characterizing the particle target density is ascertained for at least one partial volume (48) of the monitoring region (14) from the particle reflection signals (30) of each measurement. If the particle target density (52) or the variable characterizing it from the at least two measurements should differ by more than a prescribable or prescribed tolerance, it is concluded that the particle reflection signals (30) from the at least one partial volume are caused by the reflection of the transmission signals (22) at dynamic particle compositions (21).

Described herein are systems and methods for processing at least one biological sample. The systems and methods may process the biological sample, or plurality thereof, using at least one droplet. The droplet, or plurality thereof, may be manipulated using the systems and methods described herein.

A system comprises an optical air data system that measures aerosol and molecular scattering of light, and an optical instrument that measures aerosol and/or molecular scattering of light. A processor receives data from the air data system and from the optical instrument. The processor performs one or more signal analysis and data fusion methods comprising: (a) determining aerosol and/or molecular concentration from the received data, modifying a data analysis algorithm to optimize any remaining unknown parameters, and outputting enhanced air data parameters; (b) determining aerosol concentration from the received data, dynamically optimizing hardware settings in the air data system to enhance a signal level and avoid system saturation, and outputting enhanced air data parameters; or (c) determining aerosol and/or molecular concentration from the received data, estimating a confidence level of an air data algorithm, verifying optical health of the air data system, and reporting the optical health to a user.

In an embodiment, a test section comprises at least one surface defining an at least partially enclosed space. The at least partially enclosed space defines an airflow path for air to flow. The test section also comprises a nozzle disposed in the at least partially enclosed space. The nozzle is configured to spray an agricultural spray and is positioned to emit the agricultural spray such that at least a section of the agricultural spray exhibits a non-parallel angle relative to the airflow path defined by the at least partially enclosed space. The test section further comprises at least one stimulus source positioned to illuminate at least a portion of the agricultural spray adjacent to the nozzle. Additionally, the test section comprises at least one detector positioned to image at least the portion of the agricultural spray adjacent to the nozzle.

A method includes illuminating a drop with a pulse of light from a light source. A duration of the pulse of light is from about 0.0001 seconds to about 0.1 seconds. The method also includes capturing an image, video, or both of the drop. The method also includes detecting the drop in the image, the video, or both. The method also includes characterizing the drop after the drop is detected. Characterizing the drop includes determining a size of the drop, a location of the drop, or both in the image, the video, or both.

In an embodiment, a test section comprises at least one surface defining an at least partially enclosed space. The at least partially enclosed space defines an airflow path for air to flow. The test section also comprises a nozzle disposed in the at least partially enclosed space. The nozzle is configured to spray an agricultural spray and is positioned to emit the agricultural spray such that at least a section of the agricultural spray exhibits a non-parallel angle relative to the airflow path defined by the at least partially enclosed space. The test section further comprises at least one stimulus source positioned to illuminate at least a portion of the agricultural spray adjacent to the nozzle. Additionally, the test section comprises at least one detector positioned to image at least the portion of the agricultural spray adjacent to the nozzle.

A particle size distribution measuring device includes an actual spectrum obtaining unit obtaining an actual spectrum which is a light intensity spectrum; a non-target spectrum calculating unit that receives non-target particle size distribution data indicating a particle size distribution of a non-target particle group which is not a measurement target and which is accommodated in the cell and that calculates, on the basis of the non-target particle size distribution data, a non-target spectrum which is a light intensity spectrum to be obtained by irradiating the non-target particle group with light; a non-target spectrum removing unit that calculates a target spectrum which is a light intensity spectrum obtained by subtracting an influence of the non-target spectrum from the actual spectrum; and a target particle size distribution calculating unit that calculates the particle size distribution of the particle group which is the measurement target on the basis of the target spectrum.

A tomography duct for wind tunnels includes a plurality of light sources and sensors displaced around a support structure. The light sources are cycled and sensor measurements are made from sensors opposite the light sources. Tomographic algorithms are used to determine an extinction map from the sensor measurements. The extinction map provides details about particles in a cross-section of the air flow through the tomography duct.