Holographic method of dimensional inspection

Claim 1

A method of dimensionally comparing one contoured surface with another approximately similar contoured surface comprising the steps of forming a contrast pattern on one of the surfaces, making a hologram of the contrast pattern and the one surface, optically reconstructing the hologram to produce an image of the contrast pattern and the one surface, superposing the image of the contrast pattern and the one surface on the other contoured surface so that to the extent the contoured surfaces are dimensionally alike the contrast pattern will register with the other contoured surface and to the extent the surfaces are dimensionally different the contrast pattern will not register with the other surface, and determining from the pattern the difference between the one contoured surface and the other contoured surface.

Claim 2

A method of dimensionally comparing one contoured surface with another approximately similar contoured surface comprising the steps of forming a contrast pattern on one of the surfaces, making a hologram of the contrast pattern and the one surface, optically reconstructing the hologram to produce an image of the contrast pattern and the one surface, superposing the image of the contrast pattern and the one surface on the other contoured surface so that to the extent the contoured surfaces are dimensionally alike the contrast pattern will register with the other contoured surface and to the extent the surfaces are dimensionally different the contrast pattern will not register with the other surface, and determining from the pattern the difference between the one contoured surface and the other contoured surface.

Claim 3

A method of dimensionally comparing a standard article with a test article comprising the steps of forming a contrast pattern on one of the articles making a hologram of the contrast pattern and the one article, optically reconstructing the hologram to produce an image of the contrast pattern and the one article, superposing the image on the other of the articles so that if the other article is dimensionally like the said one article the contrast pattern will register with the surface of the other article and to the extent that the articles are dimensionally different the contrast pattern will not register with the surface of the other article, and determining from the pattern the difference between the one article and the other article.

Claim 4

A method of dimensionally comparing a standard article with a test article comprising the steps of forming a contrast pattern on one of the articles making a hologram of the contrast pattern and the one article, optically reconstructing the hologram to produce an image of the contrast pattern and the one article, superposing the image on the other of the articles so that if the other article is dimensionally like the said one article the contrast pattern will register with the surface of the other article and to the extent that the articles are dimensionally different the contrast pattern will not register with the surface of the other article, and determining from the pattern the difference between the one article and the other article.

Claim 5

A method of dimensionally comparing a standard article with a test article comprising the steps of forming a contrast pattern on one of the articles, making a hologram of the said contrast pattern and said one article, projecting a real image of the said contrast pattern and said one article onto the other of the articles by directing a beam of coherent light through the hologram onto the said other article so that if the other article is dimensionally like the said one article, the contrast pattern will be in focus on the said other article and to the extent that the articles are dimensionally different the contrast pattern will be out of focus, and determining from the pattern the difference between the one article and the other article.

Claim 6

A method of dimensionally comparing a standard article with a test article comprising the steps of forming a contrast pattern on one of the articles, making a hologram of the said contrast pattern and said one article, projecting a real image of the said contrast pattern and said one article onto the other of the articles by directing a beam of coherent light through the hologram onto the said other article so that if the other article is dimensionally like the said one article, the contrast pattern will be in focus on the said other article and to the extent that the articles are dimensionally different the contrast pattern will be out of focus, and determining from the pattern the difference between the one article and the other article.

Claim 7

A method of dimensionally comparing a standard article with a test article comprising the steps of forming a contrast pattern on one of the articles, making a hologram of the said contrast pattern and said one article, projecting a real image of the said contrast pattern and said one article onto the other of the articles by directing a beam of coherent light through the hologram onto the said other article so that if the other article is dimensionally like the said one aRticle, the contrast pattern will be in focus on the said other article and to the extent that the articles are dimensionally different the contrast pattern will be out of focus, and measuring the amount of dimensional difference at any point by moving the other article until the contrast pattern is in focus at that point and measuring the amount of movement.

Claim 8

A method of dimensionally comparing a standard article with a test article comprising the steps of forming a contrast pattern on one of the articles, making a hologram of the said contrast pattern and said one article, projecting a real image of the said contrast pattern and said one article onto the other of the articles by directing a beam of coherent light through the hologram onto the said other article so that if the other article is dimensionally like the said one aRticle, the contrast pattern will be in focus on the said other article and to the extent that the articles are dimensionally different the contrast pattern will be out of focus, and measuring the amount of dimensional difference at any point by moving the other article until the contrast pattern is in focus at that point and measuring the amount of movement.

Claim 9

A method of dimensionally comparing a standard article with a test article comprising the steps of forming on one of the articles a contrast pattern in light originating from a coherent light source, making a hologram of the contrast pattern and said one article by exposing a photographic plate to the contrast pattern and said one article and to the coherent light source simultaneously and developing the photographic plate, optically reconstructing the hologram to produce an image of the contrast pattern and said one article, superposing the image on the other of the articles so that to the extent the other article is dimensionally like the said one article the contrast pattern will register with the surface of the other article and to the extent that the articles are dimensionally different the contrast pattern will not register with the surface of the other article, and determining from the pattern the difference between the one article and the other article.

Claim 10

A method of dimensionally comparing a standard article with a test article comprising the steps of forming on one of the articles a contrast pattern in light originating from a coherent light source, making a hologram of the contrast pattern and said one article by exposing a photographic plate to the contrast pattern and said one article and to the coherent light source simultaneously and developing the photographic plate, optically reconstructing the hologram to produce an image of the contrast pattern and said one article, superposing the image on the other of the articles so that to the extent the other article is dimensionally like the said one article the contrast pattern will register with the surface of the other article and to the extent that the articles are dimensionally different the contrast pattern will not register with the surface of the other article, and determining from the pattern the difference between the one article and the other article.

Claim 11

A method of dimensionally comparing a standard article with a test article comprising the steps of forming on one of the articles a contrast pattern in light originating from a coherent light source, making a hologram of the contrast pattern and said one article by exposing a photographic plate to the contrast pattern and said one article and to the coherent light source simultaneously and developing the photographic plate, optically reconstructing the hologram to produce an image of the contrast pattern and said one article, superposing the image on the other of the articles so that to the extent the other article is dimensionally like the said one article the contrast pattern will register with the surface of the other article and to the extent that the articles are dimensionally different the contrast pattern will not register with the surface of the other article, and measuring the amount of dimensional difference at any point by moving the other article until the contrast pattern registers with the other article at that point and measuring the amount of movement.

Claim 12

A method of dimensionally comparing a standard article with a test article comprising the steps of forming on one of the articles a contrast pattern in light originating from a coherent light source, making a hologram of the contrast pattern and said one article by exposing a photographic plate to the contrast pattern and said one article and to the coherent light source simultaneously and developing the photographic plate, optically reconstructing the hologram to produce an image of the contrast pattern and said one article, superposing the image on the other of the articles so that to the extent the other article is dimensionally like the said one article the contrast pattern will register with the surface of the other article and to the extent that the articles are dimensionally different the contrast pattern will not register with the surface of the other article, and measuring the amount of dimensional difference at any point by moving the other article until the contrast pattern registers with the other article at that point and measuring the amount of movement.

Claim 13

A method of dimensionally comparing a standard article with a test article comprising the steps of forming on one of the articles a first contrast pattern in light originating from a coherent light source, making a hologram of the first contrast pattern and said one article by exposing a photographic plate to the first contrast pattern and said one article and to the coherent light source simultaneously and developing the photographic plate, forming on the other of the articles a second contrast pattern like the first contrast pattern, optically reconstructing the hologram to produce an image of the first contrast pattern and said one article, superposing the image on the other of the articles so that to the extent the other article is dimensionally like the said one image of the first article the contrast pattern will register with the second contrast pattern on the other article and to the extent that the articles are dimensionally different the first contrast pattern will not register with the second contrast pattern, and comparing the contrast patterns to determine the difference in the articles.

Claim 14

A method of dimensionally comparing a standard article with a test article comprising the steps of forming on one of the articles a first contrast pattern in light originating from a coherent light source, making a hologram of the first contrast pattern and said one article by exposing a photographic plate to the first contrast pattern and said one article and to the coherent light source simultaneously and developing the photographic plate, forming on the other of the articles a second contrast pattern like the first contrast pattern, optically reconstructing the hologram to produce an image of the first contrast pattern and said one article, superposing the image on the other of the articles so that to the extent the other article is dimensionally like the said one image of the first article the contrast pattern will register with the second contrast pattern on the other article and to the extent that the articles are dimensionally different the first contrast pattern will not register with the second contrast pattern, and comparing the contrast patterns to determine the difference in the articles.

Claim 15

A method of comparing a first article with a second article, each of the articles having a three-dimensional surface contour and the contour of the first article being a substantial complement of the contour of the second article, comprising the steps of forming a contrast pattern on the first article, making a first hologram of the contrast pattern and the first article, opTically reconstructing the first hologram to provide a real image of the contrast pattern and the first article, producing an inverted image of the contrast pattern and the first article by making a second hologram of the real image and optically reconstructing the second hologram, superposing the inverted image on the second article so that if the surface contours of the articles are dimensionally alike the inverted image will register with the surface of the second article and to the extent that the surface contours of the articles are dimensionally different the inverted image will not register with the surface of the second article, and determining from the inverted image the difference between the first and second articles.

Claim 16

A method of comparing a first article with a second article, each of the articles having a three-dimensional surface contour and the contour of the first article being a substantial complement of the contour of the second article, comprising the steps of forming a contrast pattern on the first article, making a first hologram of the contrast pattern and the first article, opTically reconstructing the first hologram to provide a real image of the contrast pattern and the first article, producing an inverted image of the contrast pattern and the first article by making a second hologram of the real image and optically reconstructing the second hologram, superposing the inverted image on the second article so that if the surface contours of the articles are dimensionally alike the inverted image will register with the surface of the second article and to the extent that the surface contours of the articles are dimensionally different the inverted image will not register with the surface of the second article, and determining from the inverted image the difference between the first and second articles.

Claim 17

A method of dimensionally comparing the surface of a contoured article with the surface of the same article as it originally existed at a prior time to determine dimensional changes in the article during the lapsed time comprising the steps of forming a contrast pattern on the surface of the original article, making a hologram of the contrast pattern and the surface of the original article, then after a period of time optically reconstructing the hologram to produce an image of the contrast pattern and the surface of the original article, superposing the image on the surface of the article so that to the extent that article has not dimensionally changed the contrast pattern will register with the surface of the article and to the extent that the article has changed the contrast pattern will not register with the surface of the article, and determining from the image dimensional changes in the article surface.

Claim 18

A method of dimensionally comparing the surface of a contoured article with the surface of the same article as it originally existed at a prior time to determine dimensional changes in the article during the lapsed time comprising the steps of forming a contrast pattern on the surface of the original article, making a hologram of the contrast pattern and the surface of the original article, then after a period of time optically reconstructing the hologram to produce an image of the contrast pattern and the surface of the original article, superposing the image on the surface of the article so that to the extent that article has not dimensionally changed the contrast pattern will register with the surface of the article and to the extent that the article has changed the contrast pattern will not register with the surface of the article, and determining from the image dimensional changes in the article surface.

Claim 19

A method of dimensionally comparing the surface of a contoured article with the surface of the same article as it originally existed at a prior time to determine dimensional changes in the article during the lapsed time comprising the steps of forming a contrast pattern on the surface of the original article, making a hologram of the contrast pattern and the surface, then after a period of time optically reconstructing the hologram to produce an image of the contrast pattern and the surface, superposing the image on the surface of the article so that to the extent that article has not dimensionally changed the contrast pattern will register with the surface of the article and to the extent that the article has changed the contrast pattern will not register with the surface of the article, and measuring the amount of dimensional change at any point by moving the article until the contrast pattern registers with the surface of the article at that point and measuring the amount of movement.

Claim 20

A method of dimensionally comparing the surface of a contoured article with the surface of the same article as it originally existed at a prior time to determine dimensional changes in the article during the lapsed time comprising the steps of forming a contrast pattern on the surface of the original article, making a hologram of the contrast pattern and the surface, then after a period of time optically reconstructing the hologram to produce an image of the contrast pattern and the surface, superposing the image on the surface of the article so that to the extent that article has not dimensionally changed the contrast pattern will register with the surface of the article and to the extent that the article has changed the contrast pattern will not register with the surface of the article, and measuring the amount of dimensional change at any point by moving the article until the contrast pattern registers with the surface of the article at that point and measuring the amount of movement.