Trapping and releasing particles carried by gas sample

Patent metadata

Field	Value
Publication number	US-11913859-B2
Application number	US-201917051790-A
Country	US
Kind code	B2
Filing date	Apr 15, 2019
Priority date	Apr 30, 2018
Publication date	Feb 27, 2024
Grant date	Feb 27, 2024

Abstract

According to an example aspect of the present invention, there is provided an apparatus comprising a volume for receiving a gas sample; and an ultrasonic transducer; wherein the ultrasonic transducer is caused to generate a standing wave to the volume, said standing wave comprising at least one particle trapping zone for trapping particles carried by the gas sample, and to release particles trapped to the at least particle trapping zone by decreasing power of the standing wave to at least one lower power level and/or switching off the standing wave.

First claim

The invention claimed is:

1. A method comprising:
receiving a gas sample to a volume of an on-chip fine particle sensor;
generating by a microelectromechanical, MEMS, ultrasonic transducer a standing wave to the volume, said standing wave comprising at least one particle trapping zone for trapping particles carried by the gas sample; an
releasing, by the MEMS ultrasonic transducer, particles trapped to the at least one particle trapping zone by decreasing power of the standing wave to at least one lower power level, and/or switching off, by the MEMS ultrasonic transducer, the standing wave, wherein size of the released particles is controlled by the power level of the standing wave and/or a time the at least one particle trapping zone is switched off to release plural sets of particles at different times, each set having particles of a same size range,

wherein the on-chip fine particle sensor is configured to determine a particle size distribution of the gas sample on the basis of an arrival time distribution of the released particles.

2. The method according to claim 1 , further comprising detecting particles released from the at least one particle trapping zone by a particle detection area.

3. The method according to claim 1 , wherein the power of the standing wave is adjusted to power level causing a release of a specific size or a size range of particles from the at least one particle trapping zone and/or the time the standing wave is switched off is adjusted to a time period causing a release of a specific size or a size range of particles from the at least one particle trapping zone.

4. A non-transitory computer readable medium having stored thereon a set of computer readable instructions that, when executed by at least one processor, cause an apparatus to at least:
receive a gas sample to a volume of an on-chip fine particle sensor;
generate by a microelectromechanical, MEMS, ultrasonic transducer a standing wave to the volume, said standing wave comprising at least one particle trapping zone for trapping particles carried by the gas sample; and
release, by the MEMS ultrasonic transducer, particles trapped to the at least one particle trapping zone by decreasing power of the standing wave to at least one lower power level, and/or switching off, by the MEMS ultrasonic transducer, the standing wave, wherein size of the released particles is controlled by the power level of the standing wave and/or a time the at least one particle trapping zone is switched off to release plural sets of particles at different times, each set having particles of a same size range,

wherein the on-chip fine particle sensor apparatus is configured to determine a particle size distribution of the gas sample on the basis of an arrival time distribution of the released particles.

Assignees

• Teknologian Tutkimuskeskus Vtt Oy

Inventors

• Koppinen Panu
• Sillanpää Teuvo
• Ylilammi Markku

Classifications

• G01N1/2202 Primary

  involving separation of sample components during sampling · CPC title

• B01L3/5027

  by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip · CPC title

• B01L5/00

  Gas handling apparatus (gas jars or cylinders B01L3/12; cold traps or cold baffles B01D8/00) · CPC title

• B06B1/10

  making use of mechanical energy (B06B1/18, B06B1/20 take precedence) · CPC title

• G01N1/4077

  by other techniques involving separation of suspended solids · CPC title