Electro-optical system for cancellation of the effects of red blood cells in a sample of biological cells

• US 3,893,767 A
• Filed: 10/23/1973
• Issued: 07/08/1975
• Est. Priority Date: 10/23/1973
• Status: Expired due to Term

• Current Assignee: Garret Francis Ziffer, Gerard Adelard Paquette, Mack J. Fulwyler, Michael Thomas Gilmore
• Original Assignee: Garret Francis Ziffer, Gerard Adelard Paquette, Mack J. Fulwyler, Michael Thomas Gilmore
• Inventors: Fulwyler, Mack J., Ziffer, Garret Francis, Paquette, Gerard Adelard, Gilmore, Michael Thomas
• Primary Examiner(s): McGraw, Vincent P.
• Application Number:
  US05/408,817
• Time in Patent Office: 623 Days
• Field of Search: 356/39,40,41,102,173,180,184,186,188,189,201,204,205,206 178/DIG.36
• US Class Current: 356/39
• CPC Class Codes: G01N 15/1468 with spatial resolution of the texture or inner structure of the particle
• CPC Class Codes: G01N 21/314 with comparison of measurements at specific and non-specific wavelengths dual wavelength spectrometry G01J3/427

Abstract

Method and apparatus for differentially analyzing biological cells, especially white blood cells, in a sample that includes red blood cells, without destroying or removing the red blood cells from the sample, such as a blood smear. Apparatus for illuminating the cell sample with light including that of approximately 415 nanometers in wavelength. White blood cells are almost transparent at this color; however, whenever the light of 415 nanometers wavelength passes through a portion of the illuminated sample that includes a red cell, a sufficient quantity of light energy is absorbed by the red cell to cause the resulting detection of light energy to be a tag signal below a chosen threshold value. Tag signals thus representative of the red blood cells can be stored in a memory such that the location of the red blood cells can be utilized for subsequent analysis of the sample when the sample is exposed to light of different wavelengths. In one such analysis, normal mature red blood cells can be distinguished from reticulocytes. Also, the signals representative of the red blood cells can be removed from an electrical representation of the entire sample.

Claims

1. In a method for nondestructively analyzing biological cells located in a sample including cells of at least two types supported in fixed locations relative to each other and which differentially absorb light of known wavelength, the steps of:

illuminating discretely at least parts of each of the cells at their fixed locations in the sample with first light within a first wavelength range;

detecting discretely the amount of said first light from each cell part after absorption thereby; and

generating a tag signal each time when the thus detected cell part light is different from a chosen value, said tag signal useable for indicating the fixed location in the sample of that cell part.

2. The method according to claim 1 including the steps of:

processing the thus detected first light and thereby providing electrical signals representative of each illuminated cell;

correlating the tag signals with the cell representative signals; and

blanking said cell representative signals in response to a correlation with said tag signals, thereby to eliminate electrically the electrical presence of a cell.

3. The method according to claim 2 in which said correlating includes:

storing at least one of said tag signals and said cell representative signals prior to said correlating.

4. The method according to claim 1 in which said chosen value is a threshold value;

and said generating is enabled when the detected first light falls below the threshold value.

5. The method according to claim 1 in which said first wavelength range includes 415 nanometers.

6. In the method according to claim 1 the steps of:

repeating said steps of illuminating and detecting in which said illuminating the cells is with second light within a second range of wavelengths, exclusive of at least part of said first range.

7. The method according to claim 6 which includes the steps of:

processing the thus detected second light and thereby providing electrical signals representative of each illuminated cell; and

correlating the tag signals with the cell representative signals obtained from said second light, thereby to identify electrically a specific type of biological cell.

8. The method according to claim 7 whiCh includes the step of performing a density analysis on the detected second light and thereby differentiating at least one form of a specific type of cell.

9. The method according to claim 8 in which said first light is highly absorbed by red blood cells, which cells define a specific type of cell.

10. The method according to claim 9 in which said second light is one to which normal red cells are more transparent than are reticulocytes, which define one form of a specific cell type.

11. In apparatus for nondistructively analyzing biological cells located in a sample including cells of at least two types supported in fixed locations relative to each other and which differentially absorb light of known wavelength;

illuminating means for illuminating discretely at least parts of each of the cells at their fixed locations in the sample with first light within a first wavelength range;

light detecting means for detecting discretely the amount of said first light from each cell part after absorption thereby; and

tag signal generating means coupled to said detecting means for generating a tag signal each time when the thus detected cell part light is different from a chosen value, said tag signal useable for indicating the fixed location in the sample of that cell part.

12. Apparatus according to claim 11 in which said light detecting means includes:

processing means coupled for processing the thus detected first light and thereby providing electrical signals representative of each illuminated cell; and

said apparatus further includes signal correlating means coupled to both said tag signal generating and said processing means for correlating the tag signals with the cell representative signals; and

signal blanking means coupled to said signal correlating means for blanking said cell representative signals in response to a correlation with said tag signals, thereby to eliminate electrically the electrical presence of a cell.

13. Apparatus according to claim 12 in which said signal correlating means includes output means coupled to receive said cell representative signals and be controlled by said signal blanking means so as to receive said cell representative signals only in the absence of a blanking signal from said signal blanking means.

14. Apparatus according to claim 11 in which said illuminating means includes means which define said first wavelength range to include light of approximately 415 nanometers.

15. Apparatus according to claim 12 in which said signal correlating means includes:

signal storing means for storing at least one of said tag signals and said cell representative signals prior to their correlation.

16. Apparatus according to claim 11 which includes:

threshold circuit means for defining said chosen value as a threshold value; and

said tag signal generating means is enabled when the detected first light falls below the threshold value.

17. Apparatus according to claim 11 in which said illuminating means includes light filtering means;

sample holding means is interposed between said illuminating means and said light detecting means, such that the light passes through said sample holding means and the cells; and

said light detecting means includes a vidicon, the rastering of which scans each cell by a plurality of scan lines directed toward said sample holding means.

18. Apparatus according to claim 11 in which said illuminating means includes means for illuminating the cells with second light within a second range of wavelengths, exclusive of at least part of said first range, and said light detecting means is arranged also to detect discretely the amount of said second light from each cell part after absorption thereby.

19. Apparatus according to claim 18 in which said processing means is coupled also for processing the thus detected second light and thereby providing additional electrical signals representatIve of each illuminated cell;

and said signal correlating means is coupled to both said tag signal generating means and said processing means for correlating the tag signals with the cell representative signals obtained from said second light, thereby to identify electrically a specific type of biological cell.

20. Apparatus according to claim 19 which includes:

density analysis means for performing a density analysis on the detected second light;

thereby enabling differentiating of at least one form of a specific type of cell.

21. Apparatus according to claim 20 in which said illuminating means includes light filtering means;

sample holding means is interposed between said illuminating means and said light detecting means, such that the light passes through said sample holding means and the cells; and

said light detecting means includes a vidicon, the rastering of which scans each cell by a plurality of scan lines directed toward said sample holding means.

22. Apparatus according to claim 21 in which said illuminating means includes means which defines said first light to be highly absorbed by red blood cells, which cells define said specific type of cell.

23. Apparatus according to claim 22 in which said illuminating means includes means which defines said second light to be light to which normal red blood cells are more transparent than are reticulocytes, which define one form of said specific cell type.

24. Apparatus according to claim 11 wherein said detecting means comprises:

a first filter having a narrow band pass within said first wavelength range, said first filter reflecting all light not passing therethrough;

a first photodetector positioned to detect light passing through said first filter;

a second filter positioned to receive said reflected light from said first filter, said second filter having a band pass of a first chosen wavelength of light and reflecting all other light landing thereon;

a second photodetector positioned to detect light passing through said second filter; and

a third photodetector positioned to detect all light reflected from said second filter.

25. Apparatus according to claim 24 wherein said illuminating means comprises a flying spot scanner.