Radiation sensitive film including a measuring scale

• US 20070019790A1
• Filed: 11/17/2005
• Published: 01/25/2007
• Est. Priority Date: 07/22/2005
• Status: Active Grant

• Current Assignee: Isp Investments LLC (Ashland Global Holdings, Inc.)
• Original Assignee: ISP Investments, Inc. (Ashland Global Holdings, Inc.)
• Inventors: Lewis, David, Yu, Xiang, Listl, Carl
• Granted Patent: US 7,482,601 B2
• Time in Patent Office: Days
• US Class Current: 378/163
• CPC Class Codes: A61B 5/1075 for measuring dimensions by non-invasive methods, e.g. for determining thickness of tissue layer A61B8/0858 takes precedence
• CPC Class Codes: A61N 5/1048 Monitoring, verifying, controlling systems and methods
• CPC Class Codes: G03F 7/025 Non-macromolecular photopolymerisable compounds having carbon-to-carbon triple bonds, e.g. acetylenic compounds G03F7/075 takes precedence

Abstract

An article of manufacture comprising a radiation sensitive material, and a measuring scale that is part of the radiation sensitive material. A method of measuring at least one parameter relating to an irradiated material is also described. A radiation sensitive material including a measuring scale is exposed to radiation and at least one parameter relating to one or more exposed areas of the material is measured by reference to the measuring scale on the material.

Claims

1. A radiation-sensitive material comprising:

a. a support layer;

b. a radiation sensitive composition disposed on said support; and

c. a measuring scale;

wherein said measuring scale is integral with or disposed on said radiation sensitive material.

2. The radiation-sensitive material of claim 1, wherein said radiation-sensitive material is a radiochromic self-developing film.

3. The radiation-sensitive material of claim 2, wherein said radiochromic self-developing film includes a substantially crystalline image receptive polyacetylenic compound having the structure:

A-(CH₂)_n—

C═

C—

C═

C—

(CH₂)_m—

B

wherein m and n are both independently an integer from 6 to 14 and A and B are independent from one another and are selected from the group consisting of methyl, carboxyl, hydroxy, amido, lower alkyl substituted amido, aliphatic or aromatic carboxylate ester group having up to 10 carbon atoms, mono- or di-valent carboxylate metal salt group, halo, carbamyl, lower alkyl substituted carbamyl or tosyl, triyne or tetrayne products of the above polyacetylenes having from 20 to 60 carbon atoms and a conjugated structure, and combinations thereof.

4. The radiation-sensitive material of claim 1, wherein said radiation-sensitive material comprises a radiation-sensitive film and said measuring scale is printed onto said radiation sensitive film.

5. The radiation-sensitive material of claim 4, wherein said measuring scale is printed onto said radiation sensitive film with conventional pigment ink.

6. The radiation-sensitive material of claim 1, wherein said measuring scale is more opaque to x-rays than the support layer or less opaque to x-rays than the support layer.

7. The radiation-sensitive material of claim 1, wherein said measuring scale is cut into the radiation sensitive material.

8. The radiation-sensitive material of claim 1, wherein said measuring scale is embossed onto said radiation sensitive material.

9. The radiation-sensitive material of claim 1, wherein said measuring scale is etched onto said radiation sensitive material.

10. The radiation-sensitive material of claim 1, wherein said measuring scale is linear.

11. The radiation-sensitive material of claim 10, wherein said measuring scale is a metric scale.

12. The radiation-sensitive material of claim 11, wherein said linear scale comprises a plurality of graduation marks spaced at one millimeter increments.

13. The radiation-sensitive material of claim 1, wherein said measuring scale comprises a two-dimensional scale or grid.

14. The radiation-sensitive material of claim 1, wherein said radiation-sensitive material comprises a radiochromic self-developing film that forms an image in response to radiation exposure, said image absorbing visible light over a first portion of the visible spectrum and said scale absorbing visible light over a second portion of the visible spectrum such that the scale is effectively transparent over the first portion of the visible spectrum.

15. A method of measuring at least one parameter relating to an irradiated material comprising the steps of:

a. exposing a radiation-sensitive material comprising a measuring scale to radiation to form an exposed material; and

b. measuring at least one parameter relating to one or more exposed areas of the material by reference to the measuring scale on the radiation sensitive material.

16. The method of claim 15, wherein the at least one parameter relates to the size of an exposed area or the location of an exposed area on the material.

17. The method claim 15 wherein said material is a radiochromic self-developing film.

18. The method of claim 17, wherein said said radiochromic self-developing film includes a substantially crystalline image receptive polyacetylenic compound having the structure:

A-(CH₂)_n—

C═

C—

C═

C—

(CH₂)_m—

B

wherein m and n are both independently an integer from 6 to 14 and A and B are independent from one another and are selected from the group consisting of methyl, carboxyl, hydroxy, amido, lower alkyl substituted amido, aliphatic or aromatic carboxylate ester group having up to 10 carbon atoms, mono- or di-valent carboxylate metal salt group, halo, carbamyl, lower alkyl substituted carbamyl or tosyl, triyne or tetrayne products of the above polyacetylenes having from 20 to 60 carbon atoms and a conjugated structure, and combinations thereof.

19. The method of claim 17 wherein the mono-valent carboxylate metal salt is a lithium salt.

20. The method of claim 18, wherein said step of exposing the material comprises placing said radiochromic self-developing film comprising a measuring scale between two solid blocks, positioning the film parallel to a beam of radiation and exposing the film to said beam of radiation.

21. The method of claim 20, further comprising scanning one or more of the exposed areas with an optical scanner.

22. The method of claim 21, wherein the optical scanner collects data in over more than one band of wavelengths.

23. The method of claim 22, wherein the optical scanner is an rbg color scanner.

24. The method of claim 21, wherein said at least one parameter comprises a distance from an incident surface to an exposed area.

25. The method of claim 24, further comprising the step of constructing a depth-dose curve.

26. The method of claim 17, wherein said step of exposing the material comprises exposing said film to a radioisotope radiation source.

27. The method of claim 26, wherein said radioisotope radiation source exposes a first location on said film and a second location a predetermined distance away from said first location and said at least one parameter is the distance from said first location to said second location.

28. The method of claim 17, wherein said step of exposing said material comprises placing said radiochromic self-developing film comprising a measuring scale into a CT machine and exposing said film to an x-ray beam having a first slice width.

29. The method of claim 28, wherein said first slice width is set to a nominal value between about five millimeters and about twenty millimeters.

30. The method of claim 28, wherein said at least one parameter comprises the width of the exposed area.

31. The method of claim 28, further comprising repositioning said radiochromic self-developing film and exposing to an x-ray beam having a second slice width.

32. The method of claim 17 wherein the radiochromic self-developing film forms an image in response to radiation exposure, said image absorbing visible light over a first portion of the visible spectrum and said scale absorbing visible light over a second portion of the visible spectrum such that the scale is effectively transparent over the first portion of the visible spectrum.

33. The method of claim 17, wherein said step of exposing said material comprises positioning the radiochromic self-developing film in a radiographic unit comprising an x-ray field and a light field, aligning the film with the light field, and exposing said film to x-rays.

34. The method of claim 33, wherein said measuring scale on said radiochromic self-developing film spans the edge of said light field.

35. The method of claim 34, wherein said step of measuring comprises determining the distance between said edge of said light field and said x-ray field by reference to said measuring scale.

36. The method of claim 35, wherein said measuring scale is more opaque to x-rays or less opaque to x-rays relative to the remainder of the film.

37. The method of claim 17, further comprising capturing an image of said exposed material.

38. The method of claim 37, wherein the at least one parameter comprises verifying alignment of an x-ray field with an image receptor used to capture said image.

39. A method for correcting distortion in a scanned image comprising:

a. obtaining a scanned image of a radiation-sensitive material comprising a measuring scale of known dimensions; and

b. rectifying distortion in the scanned image by adjusting the dimensions of the measuring scale in the scanned image to correspond to the known dimensions of the measuring scale in the radiation-sensitive material.

40. The method of claim 39, wherein said radiation-sensitive material comprises a radiochromic self-developing film that forms an image in response to radiation exposure, said image absorbing visible light over a first portion of the visible spectrum and said scale absorbing visible light over a second portion of the visible spectrum such that the scale is effectively transparent over the first portion of the visible spectrum.