Disposable calibration target

• US 5,924,981 A
• Filed: 04/03/1998
• Issued: 07/20/1999
• Est. Priority Date: 01/17/1996
• Status: Expired due to Term

• Current Assignee: Spectro Incorporated (Spectro Scientific, Inc.)
• Original Assignee: Spectro Incorporated (Spectro Scientific, Inc.)
• Inventors: Kellogg, Scott, Arche, Glenn Steven, Rothfritz, Robert, Samuels, Mark A., Newman, Gregory J., Kerr, Scott, Fowler, Richard Lachlan
• Primary Examiner(s): MANUEL, GEORGE C
• Application Number:
  US09/054,490
• Time in Patent Office: 473 Days
• Field of Search: 178/18.09, 250/491.1, 73/620, 73/621, 378/18, 378/207, 356/243, 356/244, 600/306, 600/309, 600/310, 600/473, 600/476, 600/477, 600/315
• US Class Current: 600/306
• CPC Class Codes: A61B 2560/0233 Optical standards
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: G01J 5/02 Constructional details
• CPC Class Codes: G01J 5/021 Probe covers for thermometers, e.g. tympanic thermometers; Containers for probe covers; Disposable probes
• CPC Class Codes: G01J 5/04 Casings
• CPC Class Codes: G01J 5/048 Protective parts
• CPC Class Codes: G01J 5/53 Reference sources, e.g. standard lamps; Black bodies
• CPC Class Codes: G01N 21/276 with alternation of sample and standard in optical path
• CPC Class Codes: G01N 21/278 Constitution of standards
• CPC Class Codes: G01N 21/645 Specially adapted constructive features of fluorimeters
• CPC Class Codes: G01N 2201/0221 Portable; cableless; compact; hand-held

Abstract

A combined infection shield and calibration or reference target for use with a measuring instrument includes a removable calibration/reference layer. The removable calibration/reference layer has predetermined optical characteristics that can be utilized to calibrate or reference the instrument. When the calibration/reference layer is removed from the remaining portions of the device, the portion of the calibration/reference layer having the predetermined optical characteristics is irrevocably altered such that the calibration/reference layer cannot be reused. The combined infection shield and target may be attached to a shield holder, which in turn is attached to an instrument. Alternatively, the infection shield and target may be attached directly to an instrument. The target may include a calibration/reference layer having a reduced strength portion which causes the target to tear or separate in a predetermined manner. Also, a double-sided adhesive layer with a gap may be used to attach the target to the remaining portions of the device, wherein the gap is arranged in a predetermined orientation with the reduced strength portion to aid tearing or separation of the target in a predetermined manner. The device may also include a cutter for causing the calibration/reference layer to tear or separate in a predetermined manner when the calibration/reference layer is removed from other portions of the device.

Claims

1. A disposable calibration device, comprising:

a double-sided adhesive layer, wherein an adhesive strength on a first side of the adhesive layer is greater than an adhesive strength on a second side of the adhesive layer; and

a calibration target arranged on at least one side of the adhesive layer.

2. The device of claim 1, wherein the calibration target is arranged on the first side of the adhesive layer.

3. The device of claim 1, wherein the calibration target includes a user graspable tab.

4. The device of claim 1, wherein the calibration target includes a reduced strength portion, and wherein the calibration target will tear or separate along the reduced strength portion when the calibration target is separated from other portions of the calibration device.

5. The device of claim 4, wherein the reduced strength portion comprises at least one of a slit, a perforation, and a crease.

6. The device of claim 1, wherein the calibration target is configured such that the calibration target will tear or separate in a predetermined manner when the calibration target is removed from other portions of the calibration device.

7. The device of claim 1, further comprising a cutter for causing the calibration target to tear or separate in a predetermined manner when the calibration target is removed from other portions of the calibration device.

8. The device of claim 7, wherein the cutter comprises one of a wire or a monofilament.

9. The device of claim 1, wherein the double-sided adhesive layer extends around all but a portion of a peripheral edge of the calibration target.

10. The device of claim 1, further comprising a shield layer arranged on a side of the double-sided adhesive layer opposite the calibration target.

11. The device of claim 10, further comprising a second double-sided adhesive layer arranged on a side of the shield layer opposite the first double-sided adhesive layer.

12. The device of claim 10, further comprising a release layer interposed between the shield layer and the double-sided adhesive layer.

13. The device of claim 1, further comprising a spacer layer interposed between the double-sided adhesive layer and the calibration target.

14. The device of claim 13, further comprising an adhesive layer interposed between the spacer layer and the calibration target.

15. The device of claim 1, wherein the calibration target includes a calibration portion having properties that are usable for calibration or reference of an instrument to which the calibration device is attached.

16. The device of claim 15, wherein the calibration portion has optical properties that are usable for calibration or reference of an optical instrument.

17. A calibration device, comprising:

a shield layer having first and second sides;

a double-sided adhesive layer having first and second sides, wherein the first side of the adhesive layer faces the first side of the shield layer and has a first adhesive strength, and wherein the second side of the adhesive layer has a second adhesive strength greater than the first adhesive strength; and

a calibration target that faces the second side of the adhesive layer.

18. The device of claim 17, wherein the calibration target includes tear means for causing the calibration target to tear or separate in a predetermined manner when the calibration target is removed from other portions of the calibration device.

19. The device of claim 18, wherein the tear means is configured so that the calibration target tears or separates across a portion of the calibration target having calibration or reference properties when the calibration target is removed from other portions of the calibration device.

20. The device of claim 18, wherein the adhesive layer extends around all but a selected portion of a periphery of the calibration target, and wherein the calibration target and the adhesive layer are oriented with respect to one another so that the adhesive layer aids tearing or separation of the calibration target in the predetermined manner.

21. The device of claim 18, wherein the tear means comprises a cutter.

22. The device of claim 21, wherein the cutter comprises one of a wire and a monofilament.

23. The device of claim 17, wherein the adhesive layer extends around all but a first portion of a periphery of the calibration target, a gap being formed in the adhesive layer adjacent the first portion of the calibration target, and wherein a slit is formed in the first portion of the calibration target, the slit causing the calibration target to tear or separate in a predetermined manner when the calibration target is removed from other portions of the calibration device.

24. The device of claim 23, wherein a user graspable tab is formed on the calibration target adjacent the first portion of the calibration target.

25. The device of claim 23, wherein the calibration target is substantially circular, the adhesive layer is substantially annular, and the slit in the calibration target extends from a peripheral edge of the calibration target towards a center of the calibration target.

26. The device of claim 25, wherein the slit extends from the peripheral edge of the calibration target for a distance less than or substantially equal to a radial width of the adhesive layer.

27. The device of claim 17, further comprising attachment means for attaching the second side of the shield layer to an instrument.

28. A disposable calibration device, comprising:

a first adhesive layer having a first side for attaching the disposable calibration device to an instrument;

a substantially transparent shield layer having a first side attached to a second side of the first adhesive layer;

a release layer having a first side attached to a second side of the shield layer;

a second adhesive layer having a first side with a first adhesive strength adhered to a second side of the release layer, and having a second side with a second adhesive strength greater than the first adhesive strength; and

a calibration target layer adhered to the second side of the second adhesive layer.

29. The device of claim 28, wherein the calibration target layer comprises:

a spacer layer having a first side adhered to the second side of the second adhesive layer;

a third adhesive layer having a first side adhered to a second side of the spacer layer; and

a calibration property layer adhered to a second side of the third adhesive layer.

30. The device of claim 28, wherein the calibration target layer includes a reduced strength portion configured such that the calibration target layer will tear or separate in a predetermined manner when the calibration target layer is removed from other portions of the calibration device.

31. The device of claim 28, further comprising a calibration device holder that is attachable to a measuring instrument, wherein the first side of the first adhesive layer is attached to the calibration device holder.

32. The device of claim 28, further comprising a cutter that causes the calibration target layer to tear or separate in a predetermined manner when the calibration target layer is removed from other portions of the calibration device.

33. The device of claim 32, wherein the cutter is one of a wire and a monofilament.

34. A disposable calibration device, comprising:

a calibration layer;

means for attaching the calibration layer to a measuring instrument; and

a cutter that causes the calibration layer to tear or separate in a predetermined manner when the calibration layer is removed from other portions of the calibration device.

35. The device of claim 34, wherein the calibration layer includes a reduced strength portion that helps to cause the calibration layer to tear or separate in a predetermined manner when the calibration layer is removed from other portions of the calibration device.

36. The device of claim 34, wherein the attaching means comprises an adhesive layer.

37. The device of claim 34, wherein the attaching means comprises a mechanical attachment device.

38. The device of claim 37, wherein the mechanical attachment device is one of a staple, a pin, a clip, a screw and a clamp.

39. The device of claim 34, wherein the cutter is one of a wire and a monofilament.

40. A method of measuring an optical property, comprising the steps of:

attaching a reference target to a measuring instrument;

conducting at least one reference measurement on the reference target to determine a reference value;

conducting at least one object measurement on an object to determine an object value; and

calculating an optical property of the object based on a relationship between the object value and the reference value.

41. The method of claim 40, wherein the step of conducting at least one reference measurement comprises:

conducting a measurement on the reference target with a light source of the measuring instrument turned off to obtain a dark reference reading;

conducting a measurement on the reference target with the light source of the measuring instrument turned on to obtain a reference reading; and

subtracting the dark reference reading from the reference reading to obtain the reference value.

42. The method of claim 40, wherein the step of conducting at least one object measurement comprises:

conducting a measurement on an object with a light source of the measuring instrument turned off to obtain a dark object reading;

conducting a measurement on the object with a light source of the measuring instrument turned on to obtain an object reading; and

subtracting the dark object reading from the object reading to obtain the object value.

43. The method of claim 40, wherein the step of calculating an optical property comprises calculating a logarithm of a ratio of the object value to the reference value.

44. The method of claim 40, wherein the step of conducting a reference measurement and the step of conducting an object measurement both comprise correcting for stray light.