Method for particle analysis and particle analysis system

Abstract

In a known method for particle analysis, at least part of a particle accumulation is illuminated on a substantially planar substrate and imaged, a measurement area of the particle accumulation being displaced grid by grid, and imaging data obtained on the measurement area being evaluated with respect to particle characteristics. Starting from this, to provide a method for particle analysis that also in an automatic microscopic analysis of a particle accumulation with metallic particles supplies an exact analysis result in a fast and reproducible manner, it is suggested according to the invention that on each measurement area a first series of imaging data should be generated from an image obtained with light of a first polarization state which masks reflections of metallic particles, and a second series of imaging data should be generated from an image obtained with light of a second polarization state which does not mask reflections of metallic particles, the two series of imaging data being compared and metallic particles being detected in this process and said particles being evaluated with respect to number and size, the first polarization state and the second polarization state being set by adjusting a polarization device by means of an electrical adjusting device.

Description

The invention shall now be explained in more detail with reference to an embodiment and a patent drawing, which shows in detail in

FIG. 1 an embodiment of the analysis system of the invention with a reflected light stereomicroscope, in a schematic view;

FIG. 2 an image of a particle accumulation, obtained with crossed polarizers, as part of a first method step of the analysis method of the invention;

FIG. 3 the image of the particle accumulation according to FIG. 2 illuminated with non-polarized light, as part of a second method step of the analysis method according to the invention; and

FIG. 4 an illustration of the particle accumulation analyzed and calculated on the basis of the images of FIG. 2 and FIG. 3, with the metallic particles being marked.

Claims

1. A particle analysis system comprising: an optical imaging device imaging a particle accumulation onto a substantially planar substrate,an illuminating device illuminating at least part of a particle accumulation,a polarization device including an optical polarizer and an optical analyzer,a positioning device displacing an illuminated measurement area of the particle accumulation grid by grid, andan evaluating device obtaining and evaluating imaging data generated by the imaging device on each measurement area, wherein the polarization device includes an electrical adjusting device, the optical polarizer and the optical analyzer being adjustable using the electrical adjusting device relative to each other in a first polarizer position and in a second polarizer position, and wherein the imaging device generates imaging data of the particle accumulation with the first polarizer position and with the second polarizer position in a software-controlled manner on each measurement area.

2. The analysis system according to claim 1 wherein the optical imaging device comprises a reflecting light stereomicroscope.

3. The analysis system according to claim 1 wherein the imaging device comprises a ring light on a lens barrel of a microscope.

4. The analysis system according to claim 3 wherein the optical polarizer is configured as a polarization ring film and arranged in an illumination beam of the ring light.

5. The analysis system according to claim 4 wherein the polarization ring film is adjustable by means of the electrical adjusting device.

6. The analysis system according to claim 1 wherein the positioning device comprises a multi-axis controller.

7. The analysis system according to claim 1 wherein the illuminating device comprises an autofocusing system.

8. A method for particle analysis, said method comprising: illuminating at least part of a particle accumulation on a substantially planar substrates;imaging, an illuminated measurement area of the particle accumulation being displaced grid by grid;evaluating imaging data obtained on the measurement area with respect to particle characteristics, wherein on each measurement area a first series of imaging data is generated from an image obtained with light of a first polarization state that masks reflections of metallic particles, and a second series of imaging data is generated from an image obtained with light of a second polarization state that does not mask reflections of metallic particles, the first and second series of imaging data being compared so as to detect metallic particles, and said metallic particles being evaluated with respect to number and size, the first polarization state and the second polarization state being set by adjusting a polarization device using an electrical adjusting device.

9. The method according to claim 8 wherein the image of the measurement area is produced by means of a reflecting light stereomicroscope.

10. The method according to claim 8 wherein a ring light is used on a lens barrel of a microscope so as to illuminate the particle accumulation.

11. The method according to claim 10 wherein the first polarization state and the second polarization state of the light are set by means of an adjustable polarizer that is configured as a polarization ring film and arranged in the illumination beam of the ring light.

12. The method according to claim 11 wherein the polarization ring film is electrically adjusted so as to set the first polarization state and the second polarization state.

13. The method according to claim 8 wherein for each measurement area the first series of imaging data is evaluated before the second series of imaging data.