Method for detecting a response of each probe zone on a test strip

• US 7,822,245 B2
• Filed: 02/13/2007
• Issued: 10/26/2010
• Est. Priority Date: 01/02/2003
• Status: Expired due to Fees

• Current Assignee: Intellectual Ventures I LLC (Intellectual Ventures LLC)
• Original Assignee: Transpacific Systems LLC (Intellectual Ventures LLC)
• Inventors: Wang, Kuo-Jeng
• Primary Examiner(s): Bella; Matthew C
• Assistant Examiner(s): MACKOWEY, ANTHONY M
• Application Number:
  US11/674,593
• Publication Number:
  US 20070196862A1
• Time in Patent Office: 1,351 Days
• Field of Search: 382/128, 382/129, 382168-172, 382/164, 382/165, 382/174, 382/193, 382/199, 382/201, 382/220, 435/4, 422/82.05, 422/56, 356/243.1, 356/243.5
• US Class Current: 382/128
• CPC Class Codes: G01N 21/27 using photo-electric detection G01N21/31 takes precedence; circuits for computing concentration logarithmic circuits G06G7/24; photometric circuits in general G01J
• CPC Class Codes: G01N 21/8483 Investigating reagent band test-element handling not specific to a test method G01N33/4875; analytical elements specific to chemical analysis of biological material G01N33/52; autometer with reagent band G01N35/04
• CPC Class Codes: Y10S 435/805 Test papers

Abstract

A method for detecting a response of each probe zone on a test strip is provided. The present method includes providing a test strip having a color pattern displayed thereon. The color pattern occurs in response to a tested solution contacting with the test strip and including a plurality of color lines displayed in sequence from a bottom portion of the test strip to a top portion thereof. The site of each color line represents a probe zone of the test strip. Capturing a whole image of the test strip and selecting at least one scan line perpendicular to the image of the color lines therefrom. Setting a pixel position of the scan line having a minimum pixel value corresponding to a bottom edge of the test strip and using the pixel position as a reference to identify respective pixel positions of the color lines on the scan line so as to identify the image positions thereof on the whole image. A response of each probe zone of the test strip related to a gray level of a corresponding image position is thus obtained.

Claims

1. A method, comprising:

providing a test strip having a background and a pattern displayed thereon, the pattern occurring in response to a tested solution contacting a first region of the test strip, the pattern having a plurality of test lines that each correspond to a probe zone configured to indicate the presence or absence of a corresponding substance in the tested solution;

capturing an image of the test strip using a scanning device;

selecting at least one scan line from the image, the scan line intersecting image lines of the pattern in the captured image;

identifying pixel positions located at intersections of the scan line and the image lines of the pattern in the captured image;

selecting a reference pixel position associated with an edge of the test strip; and

correlating each of the identified pixel positions with a particular one of the probe zones using the reference pixel position and a preset sequence of the probe zones.

2. The method of claim 1, wherein the reference pixel position is selected by locating a pixel in the selected scan line of the captured image having a minimum red pixel value.

3. The method of claim 1, wherein the reference pixel position is selected by locating a pixel in the selected scan line of the captured image having a minimum average pixel value formed of red, green, and blue pixel values.

4. The method of claim 1, wherein the background is white.

5. The method of claim 1, wherein the tested solution comprises a biological fluid collected from a subject.

6. The method of claim 5, wherein the biological fluid comprises a urine specimen fluid.

7. The method of claim 1, wherein the test strip includes a second region configured to have a response indicating whether the tested solution has moved through all the probe zones, wherein the second region is positioned further from the first region than the probe zones such that the probe zones are positioned between the first region and the second region.

8. The method of claim 7, further comprising associating a respective pixel position of the scan line with the second region, wherein the pixel position that is associated with the second region is further from the reference pixel position than the respective pixel positions that are associated with the image lines.

9. The method of claim 1, wherein the probe zones of the test strip include at least one particular probe zone between top and bottom probe zones of the test strip, and wherein at least a particular one of the identified pixel positions of the scan line that are positioned at the intersections of the scan line and the image lines corresponds to the particular probe zone.

10. The method of claim 1, wherein at least one of the probe zones is configured to detect a different drug of abuse than another one of the probe zones.

11. An article of manufacture including a non-transitory computer-readable medium having instructions stored thereon that, if executed by a computing device, cause the computing device to perform operations comprising:

capturing an image of a test strip;

wherein the test strip has a pattern displayed thereon, the pattern occurring in response to a tested solution contacting a first region of the test strip and including a plurality of test lines that each correspond to a probe zone configured to indicate the presence or absence of a corresponding substance in the tested solution;

selecting at least one scan line from the image, the scan line intersecting image lines of the pattern of the captured image;

identifying pixel positions located at intersections of the scan line and the image lines of the pattern in the captured image;

selecting a reference pixel position associated with the image of the test strip; and

correlating each of the identified pixel positions with a particular one of the probe zones using the reference pixel position and a preset sequence of the probe zones.

12. The article of manufacture of claim 11, wherein the reference pixel position is selected by locating a pixel in the selected scan line of the captured image having a minimum red pixel value.

13. The article of manufacture of claim 11, wherein the reference pixel position is selected by locating a pixel in the selected scan line of the captured image having a minimum average pixel value formed of red, green, and blue pixel values.

14. The article of manufacture of claim 11, wherein the test strip has a white base.

15. The article of manufacture of claim 11, wherein the tested solution comprises a biological fluid collected from a subject.

16. The article of manufacture of claim 15, wherein the biological fluid comprises a urine specimen fluid.

17. The article of manufacture of claim 11, wherein the image of the test strip is captured using a charge-coupled device.

18. The article of manufacture of claim 11, wherein the test strip includes a second region configured to have a response indicating whether the tested solution has moved through all the probe zones, wherein the second region is positioned further from the first region than the probe zones such that the probe zones are positioned between the first region and the second region.

19. The article of manufacture of claim 18, wherein the instructions stored thereon, if executed by the computing device, cause the computing device to perform operations comprising using the reference pixel position to identify a respective pixel position of the second region on the scan line.

20. The article of manufacture of claim 11, wherein the probe zones of the test strip include at least one particular probe zone between top and bottom probe zones of the test strip, and wherein at least a particular one of the identified pixel positions of the scan line that are positioned at the intersections of the scan line and the image lines corresponds to the particular probe zone.

21. The article of manufacture of claim 11, wherein at least one of the probe zones is configured to detect a different drug of abuse than another one of the probe zones.

22. An apparatus, comprising:

means for capturing an image of a test strip;

wherein the test strip has a pattern displayed thereon, the pattern occurring in response to a tested solution contacting a first region of the test strip and including a plurality of test lines that each correspond to a probe zone configured to indicate the presence or absence of a corresponding substance in the tested solution;

means for identifying pixel positions located at intersections of a scan line and image lines of the pattern in the captured image;

means for selecting at least one scan line from the image, the scan line intersecting one of the image lines of the pattern of the captured image;

means for selecting a reference pixel position associated with the image of the test strip; and

means for correlating each of the identified pixel positions with a particular one of the probe zones using the reference pixel position and a preset sequence of the probe zones.

23. The apparatus of claim 22, wherein the reference pixel position is selected by locating a pixel in the selected scan line of the captured image having a minimum red pixel value.

24. The apparatus of claim 22, wherein the reference pixel position is selected by locating a pixel in the selected scan line of the captured image having a minimum average pixel value formed of red, green, and blue pixel values.

25. The apparatus of claim 22, wherein the test strip includes a second region configured to have a response indicating whether the tested solution has moved through all the probe zones, wherein the second region is positioned further from the first region than the probe zones such that the probe zones are positioned between the first region and the second region.

26. The apparatus of claim 25, further comprising means for identifying a respective pixel position of the second region.

27. The apparatus of claim 25, wherein the first and second regions comprise ends of the test strip and the pattern is displayed on a body of the test strip.

28. The apparatus of claim 27, wherein the first region is located on a bottom end of the test strip and the second region is located on a top end of the test strip.

29. The apparatus of claim 22, wherein the probe zones of the test strip include at least one particular probe zone between top and bottom probe zones of the test strip, and wherein at least a particular one of the identified pixel positions of the scan line that are positioned at the intersections of the scan line and the image lines corresponds to the particular probe zone.

30. The apparatus of claim 22, wherein at least one of the probe zones is configured to detect a different drug of abuse than another one of the probe zones.

31. An apparatus, comprising:

an image capturing device configured to capture an image of a test strip;

wherein the test strip has a pattern displayed thereon, the pattern occurring in response to a tested solution contacting a first region of the test strip and including a plurality of test lines that each correspond to a probe zone configured to indicate the presence or absence of a corresponding substance in the tested solution; and

a computing device configured to connect to the image capturing device, wherein the computing device is configured to

select at least one scan line from the image, the scan line intersecting image lines of the pattern in the captured image;

identify pixel positions located at intersections of the scan line and the image lines of the pattern in the captured image;

select a reference pixel position associated with the image of the test strip; and

correlate each of the identified pixel positions with a particular one of the probe zones using the reference pixel position and a preset sequence of the probe zones.

32. The apparatus of claim 31, wherein the reference pixel position is selected by locating a pixel in the selected scan line of the captured image having a minimum red pixel value.

33. The apparatus of claim 31, wherein the reference pixel position is selected by locating a pixel in the selected scan line of the captured image having a minimum average pixel value formed of red, green, and blue pixel values.

34. The apparatus of claim 31, wherein the test strip includes a second region configured to have a response indicating whether the tested solution has moved through all the probe zones, wherein the second region is positioned further from the first region than the probe zones such that the probe zones are positioned between the first region and the second region.

35. The apparatus of claim 34, wherein the computing device is configured to identify a respective pixel position of the second region.

36. The apparatus of claim 31, wherein the probe zones of the test strip include at least one particular probe zone between top and bottom probe zones of the test strip, and wherein at least a particular one of the identified pixel positions of the scan line that are positioned at the intersections of the scan line and the image lines corresponds to the particular probe zone.

37. The apparatus of claim 34, wherein the first and second regions comprise ends of the test strip and the pattern is displayed on a body of the test strip.

38. The apparatus of claim 37, wherein the first region is located on a bottom end of the test strip and the second region is located on a top end of the test strip.

39. The apparatus of claim 31, wherein at least one of the probe zones is configured to detect a different drug of abuse than another one of the probe zones.