US4876455A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fiber optic solder joint inspection system
Assignee: Micron Technology Inc
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Filing: 1988-02-25
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Granted: 1989-10-24
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Expires: 2008-02-25
Abstract
Abstract The invention is an automated solder joint inspection system for determining the quality of a specular soldered joint through examination of the shape of the joint surface using a series of point light sources and the associated highlight reflections from the joint surface. The light from the point light sources, which is directed toward the solder joint, is reflected in a pattern from the solder joint to an array of light responsive transducers, such as a camera, at a fixed location. Utilizing the intensity values from the light responsive transducer array, a binary grid map is generated for the reflections from each point light source. Using known surface features of solder joints along with curve fitting techniques, a series of grid maps may be mathematically interpreted to reconstruct the solder joint surface. A rule-based system, through comparison with acceptable solder joint surface features, evaluates and classifies the joint for an acceptability determination.
Inventors
- 👤 Arthur C. Sanderson
- 👤 Lee E. Weiss
- 👤 Shree K. Nayar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:24
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/95; G01N21/956; G01N21/95684; G01N21/8851; G01N2021/8887; G01N2021/95638; G01N2021/95646; G01N2201/00; G01N2201/10; G01N2201/102; G01N2201/108; G01N2201/1085
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
112 words
A method for determining the shape of an object having a specular surface comprising the steps of: (a) projecting sequentially toward the object the light from each of a plurality of point light sources which are arranged in a fixed configuration about a common site at which the object is placed for inspection; (b) viewing the object at the common site to detect light patterns caused by the reflections of light of each point light source from the object surface; (c) interpreting the light patterns to determine the surface orientation of points on the object surface; and (d) reconstructing the object surface profile using the surface orientations of points on the object.
Claim 2
Independent Claim
112 words
A method for determining the shape of an object having a specular surface comprising the steps of: (a) projecting sequentially toward the object the light from each of a plurality of point light sources which are arranged in a fixed configuration about a common site at which the object is placed for inspection; (b) viewing the object at the common site to detect light patterns caused by the reflections of light of each point light source from the object surface; (c) interpreting the light patterns to determine the surface orientation of points on the object surface; and (d) reconstructing the object surface profile using the surface orientations of points on the object.
Claim 3
Dependent Claim
38 words
The method of claim 1 wherein the projecting step utilizes light from a plurality of light sources which are arranged in a fixed arcuate two-dimensional configuration about a common site at which the object is placed for inspection.
Claim 4
Dependent Claim
37 words
The method of claim 1 wherein the projection step utilizes light from a plurality of light sources which are arranged in a fixed hemispherical configuration about a common site at which the object is placed for inspection.
Claim 5
Dependent Claim
61 words
The method of claim 1 wherein the interpreting step is comprised of converting an analog signal representing intensity into a digital signal and utilizing a threshold value to eliminate signals produced by light not directly reflected from the object surface, thereby producing a series of binary signals indicating whether or not a surface reflects light from specific point light source locations.
Claim 6
Dependent Claim
29 words
The method as defined in claim 1, further comprising, for evaluating the object, comparing the local surface features of the object profile to those of a desirable object profile.
Claim 7
Dependent Claim
25 words
The method as defined in claim 1 wherein viewing the object at the common site is done from a single direction at a fixed location.
Claim 8
Dependent Claim
30 words
The method as defined in claim 1 wherein viewing the object at the common site is done from a different singular direction at each of a plurality of fixed locations.
Claim 9
Dependent Claim
128 words
A non-contact inspection apparatus for determining the shape of an object having a specular surface comprising: (a) an array of point light sources spaced apart from one another in a fixed configuration about a common site at which the object is placed for inspection; (b) means for sequentially projecting each of the point light sources for emitting light toward the object; (c) a means for viewing the object at the common site to detect light patterns caused by the reflections of light of each point light source from the object surface; (d) a means for interpreting the light patterns to determine the surface orientation of points on the object; and (e) a means for reconstructing the object surface profile using the surface orientation of points on the object.
Claim 10
Dependent Claim
128 words
A non-contact inspection apparatus for determining the shape of an object having a specular surface comprising: (a) an array of point light sources spaced apart from one another in a fixed configuration about a common site at which the object is placed for inspection; (b) means for sequentially projecting each of the point light sources for emitting light toward the object; (c) a means for viewing the object at the common site to detect light patterns caused by the reflections of light of each point light source from the object surface; (d) a means for interpreting the light patterns to determine the surface orientation of points on the object; and (e) a means for reconstructing the object surface profile using the surface orientation of points on the object.
Claim 11
Dependent Claim
25 words
The apparatus of claim 8, wherein the point light sources of the array are spaced apart from one another in a fixed arcuate two-dimensional configuration.
Claim 12
Dependent Claim
24 words
The apparatus of claim 8, wherein the point light sources of the array are spaced apart from one another in a fixed hemispherical configuration.
Claim 13
Dependent Claim
48 words
The apparatus of claim 8, wherein the means for viewing the object at the common site for detecting light patterns is comprised of an array of light responsive transducers, such as a solid state camera, that produces an analog signal such as a voltage value for each transducer.
Claim 14
Dependent Claim
28 words
The apparatus of claim 8, further comprising means for comparing the local surface features of the object profile to those of a desirable profile to evaluate the object.
Claim 15
Dependent Claim
16 words
The apparatus of claim 12, wherein the object is a solder joint having a specular surface.
Claim 16
Dependent Claim
41 words
The apparatus of claim 8, wherein the means for viewing the object at the common site for detecting light patterns is comprised of an array of light responsive transducers oriented toward the object in a single direction at a fixed location.
Claim 17
Dependent Claim
46 words
The apparatus of claim 8, wherein the means for viewing the object at the common site for detecting light patterns is comprised of an array of light responsive transducers oriented toward the object from a different singular direction at each of a plurality of fixed locations.
Claim 18
Dependent Claim
127 words
A non-contact inspection apparatus for determining the shape of an object having specular surfaces comprising: (a) an array of point light sources spaced apart from one another in a fixed hemispherical configuration about a common site at which the object is placed for inspection; (b) means for sequentially activating each of the point light sources for emitting light toward the object; (c) means for detect the variety of light patterns caused by the reflections of light from each point light source at each location from the object surface; (d) means for interpret the series of light patterns to determine the surface orientation of points on the object; and (e) means for reconstruct the object profile using the surface orientation of a variety of points on the object.
Claim 19
Dependent Claim
127 words
A non-contact inspection apparatus for determining the shape of an object having specular surfaces comprising: (a) an array of point light sources spaced apart from one another in a fixed hemispherical configuration about a common site at which the object is placed for inspection; (b) means for sequentially activating each of the point light sources for emitting light toward the object; (c) means for detect the variety of light patterns caused by the reflections of light from each point light source at each location from the object surface; (d) means for interpret the series of light patterns to determine the surface orientation of points on the object; and (e) means for reconstruct the object profile using the surface orientation of a variety of points on the object.
Claim 20
Independent Claim
133 words
A method for determining the shape of an object having a specular surface comprising the steps of: (a) projecting sequentially toward the object the light from each of a plurality of point light sources which are arranged in a fixed hemispherical configuration about a common site at which the object is placed for inspection; (b) means for viewing the object at the common site to detect light patterns caused by the reflections of light of each point light source from the object surface wherein viewing the object at the common site is done from a single direction at a fixed location; (c) interpreting the light patterns to determine the surface orientation of points on the object surface; and (d) reconstructing the object surface profile using the surface orientations of points on the object.
Claim 21
Independent Claim
133 words
A method for determining the shape of an object having a specular surface comprising the steps of: (a) projecting sequentially toward the object the light from each of a plurality of point light sources which are arranged in a fixed hemispherical configuration about a common site at which the object is placed for inspection; (b) means for viewing the object at the common site to detect light patterns caused by the reflections of light of each point light source from the object surface wherein viewing the object at the common site is done from a single direction at a fixed location; (c) interpreting the light patterns to determine the surface orientation of points on the object surface; and (d) reconstructing the object surface profile using the surface orientations of points on the object.
References Cited (Backward Citations)
US3976382A
Cited
US4185918A
Cited
US4508452A
Cited
US4238147A
Cited
US4472056A
Cited
US4473750A
Cited
US4427880A
Cited
US4452534A
Cited
US4657393A
Cited
US4650333A
Cited
US4634879A
Cited
US4748335A
Cited
US4695163A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-23 | 1993-04-24 | 1993-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-23 | 1997-04-24 | 1997-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-23 | 2001-04-24 | 2001-10-24 | $7700.00 | Window Closed / Lapsed |