Particle analyzing method and apparatus

A method for analyzing solid or liquid particles in a gas stream of gas molecules, where the particles each have a mass which is orders of magnitude greater than that of said gas molecules, comprising:

• passing said particles along a predetermined path free of support from a substrate;
• applying electromagnetic radiation to at least one particle while it passes along said path, at an intensity high enough to vaporize and ionize it;
• and
• detecting the ions generated from the vaporized particle.

A method for analyzing solid or liquid particles in a gas stream, where each particle has a mass that is a plurality of orders of magnitude greater than the mass of each gas molecule comprising:

• passing said particles along a predetermined path free of support from a substrate, to a heated body which is hot enough to vaporize the particle;
• directing a stream of ionizing electrons at the vapor to ionize it;
• and
• detecting the resulting ions.

Apparatus for analyzing solid or liquid particles generally on the order of one micron diameter, that are entrained in a gas, comprising:

• means for passing said particles in free flight along a predetermined path;
• means for vaporizing and ionizing at least one of said particles while it passes along said path, including means for applying electromagnetic radiation of an intensity to vaporize the particle while it remains in free flight;
• and
• means for detecting the ions generated from the vaporized particle.

Apparatus for analyzing solid or liquid particles generally on the order of one micron diameter, that are entrained in a gas, comprising:

• means for passing said particles in free flight along a predetermined path;
• means for vaporizing and ionizing at least one of said particles while it passes along said path, including a heated body located along said path for vaporizing said particles, and an electron source aimed to apply electrons to a location near said heated body to ionize the vapor;
• and
• means for detecting the ions generated from the vaporized particle.

In apparatus for analyzing particles entrained in a gas, wherein the particles each have a mass which is orders of magnitude greater than the mass of each of the molecules of said gas, the improvement of means for providing a stream of particles, comprising:

• a narrow tube having a length which is a plurality of times greater than its inside diameter, said tube having an entrance end for receiving gas with particles entrained therein, and an exit end;
• a skimmer having a narrow opening spaced from but aligned with said narrow tube, to receive particles moving in a largely straight path from said tube to said skimmer;
• a housing surrounding the region between said narrow tube and said skimmer, and forming said region with a cross-section much larger than the cross-section of said tube, to permit the dispersion of gas therein to minimize the amount of gas reaching said skimmer opening;
• means for evacuating gas from said region;
• and
• means for applying optical radiation to a path location which lies beyond an end of said skimmer which is opposite said tube, in an intensity to ionize and vaporize free particles moving past said path location, and means for detecting the resulting ions.

In apparatus for analyzing particles entrained in a gas, wherein the particles each have a mass which is orders of magnitude greater than the mass of each of the molecules of said gas, the improvement of means for providing a stream of particles, comprising:

• a narrow tube having a length which is a plurality of times greater than its inside diameter, said tube having an entrance end for receiving gas with particles entrained therein, and an exit end;
• a skimmer having a narrow opening spaced from but aligned with said narrow tube, to receive particles moving in a largely straight path from said tube to said skimmer;
• a housing surrounding the region between said narrow tube and said skimmer, and forming said region with a cross-section much larger than the cross-section of said tube, to permit the dispersion of gas therein to minimize the amount of gas reaching said skimmer opening;
• means for evacuating gas from said region;
• and
• means for applying sufficient heat to particles moving past a path location beyond an end of said skimmer which is opposite said tube, to vaporize the particles, and means for applying an electron stream to a location at least near said path location to ionize the vapor.