Patent US6207946B1 successfully refreshed from Google Patents.
US6207946B1
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Adaptive lighting system and method for machine vision apparatus
Assignee: ASTI Holdings Ltd
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Filing: 1999-07-26
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Granted: 2001-03-27
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Expires: 2019-07-26
Abstract
Abstract A variable intensity lighting system for use with a machine vision apparatus for capturing high contrast images of articles to be inspected, such as semiconductor packages, includes an LED or optical fiber element and flash lamp array configured in multiple segments which are operable to be controlled as to light output intensity by a programmable intensity control circuit operably connected to a microprocessor. The intensity control circuit includes multiple digital potentiometers operable to control selected segments of the lighting array. The control circuit is adapted to control up to 64 segments of the lighting array individually at 64 incremental intensity levels, respectively. The control circuit may include a light failure module to detect a segment failure or a reversed connection. A processor is programmed to calculate a median gray value from a predetermined number of camera pixel intensity values of the article being viewed under the lighting array to readjust the intensity of the lighting until a setting with suitable contrast is reached. Each article being viewed may have a suitable identifier, such as a dimple or notch which is viewed by the camera to determine the optimum intensity level.
Inventors
- 👤 Noor Ashedah Binti Jusoh
- 👤 Tan Seow Hoon
- 👤 Sreenivas Rao
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:24
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/8806
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
188 words
An adaptive lighting system for a machine vision apparatus comprising: an array of plural optical fiber light emitting elements supported for projecting light from one end thereof, respectively, on an article to be viewed, said optical fiber elements being disposed in proximity to plural flash lamps of said system for generating a source of light to be projected through said optical fiber element and on said article; a camera for recording an image of said article when illuminated by said array; a light intensity control circuit operably coupled to said array for varying the intensity of light emitted by selected segments of said array to adjust the illumination of said article viewed by said camera; a processor operably connected to said camera and to said intensity control circuit for adjusting the light intensity emitted by said array to provide an image of said article recorded by said camera; and a flash lamp driver and trigger circuit operably connected between respective ones of said flash lamps and said light intensity control circuit for operating said flash lamps in response to a signal generated by said light intensity control circuit.
Claim 2
Dependent Claim
188 words
An adaptive lighting system for a machine vision apparatus comprising: an array of plural optical fiber light emitting elements supported for projecting light from one end thereof, respectively, on an article to be viewed, said optical fiber elements being disposed in proximity to plural flash lamps of said system for generating a source of light to be projected through said optical fiber element and on said article; a camera for recording an image of said article when illuminated by said array; a light intensity control circuit operably coupled to said array for varying the intensity of light emitted by selected segments of said array to adjust the illumination of said article viewed by said camera; a processor operably connected to said camera and to said intensity control circuit for adjusting the light intensity emitted by said array to provide an image of said article recorded by said camera; and a flash lamp driver and trigger circuit operably connected between respective ones of said flash lamps and said light intensity control circuit for operating said flash lamps in response to a signal generated by said light intensity control circuit.
Claim 3
Dependent Claim
39 words
The system set forth in claim 1 wherein: said array comprises plural rows of light emitting elements arranged in a generally rectangular pattern about an aperture in said array for projecting an image from said article to said camera.
Claim 4
Dependent Claim
50 words
The system set forth in claim 1 wherein: said processor includes a memory circuit, said memory circuit having data stored therein representing at least one of a predetermined number of images of a predetermined number of articles and values of light intensity emittable by said selected segments of said array.
Claim 5
Dependent Claim
36 words
The system set forth in claim 1 including: a control circuit for generating a flash lamp trigger signal for selectively energizing said flash lamps, respectively, at least one of momentarily and continuously at a predetermined frequency.
Claim 6
Dependent Claim
226 words
An adaptive lighting system for a machine vision apparatus for inspecting selected semiconductor packages, said system comprising: an array of plural light emitting diodes divided into a plurality of segments of at least one light emitting diode per segment and disposed in a pattern for illuminating a semiconductor package for providing an image of said semiconductor package suitable for inspection of said semiconductor package; a camera disposed with respect to said array for recording an image of said semiconductor package when said semiconductor package is illuminated by said array; a light intensity control circuit operably coupled to said array for varying the intensity of light emitted by selected segments of said array to provide an image of said semiconductor package having a predetermined resolution; a processor operably connected to said camera and to said intensity control circuit for adjusting the light intensity emitted by selected segments of said array to provide an image of said package corresponding substantially to said image of predetermined resolution; and said intensity control circuit includes a plurality of digital potentiometers operably connected to respective ones of said segments of said array and operable to receive control signals from said processor for causing predetermined light intensities to be emitted by the light emitting diodes of said segments, respectively, to obtain an image of said package corresponding to said image of predetermined resolution.
Claim 7
Dependent Claim
226 words
An adaptive lighting system for a machine vision apparatus for inspecting selected semiconductor packages, said system comprising: an array of plural light emitting diodes divided into a plurality of segments of at least one light emitting diode per segment and disposed in a pattern for illuminating a semiconductor package for providing an image of said semiconductor package suitable for inspection of said semiconductor package; a camera disposed with respect to said array for recording an image of said semiconductor package when said semiconductor package is illuminated by said array; a light intensity control circuit operably coupled to said array for varying the intensity of light emitted by selected segments of said array to provide an image of said semiconductor package having a predetermined resolution; a processor operably connected to said camera and to said intensity control circuit for adjusting the light intensity emitted by selected segments of said array to provide an image of said package corresponding substantially to said image of predetermined resolution; and said intensity control circuit includes a plurality of digital potentiometers operably connected to respective ones of said segments of said array and operable to receive control signals from said processor for causing predetermined light intensities to be emitted by the light emitting diodes of said segments, respectively, to obtain an image of said package corresponding to said image of predetermined resolution.
Claim 8
Dependent Claim
24 words
The system set forth in claim 5 wherein: said intensity control circuit includes constant current sources interconnected between said potentiometers and said segments, respectively.
Claim 9
Dependent Claim
40 words
The system set forth in claim 5 including: means for switching output signals from said intensity control circuit between selected ones of said segments to enable said camera to capture images of said package having respective different lighting imposed thereon.
Claim 10
Dependent Claim
29 words
The system set forth in claim 5 including: a circuit operable to provider an output signal to cause all segments of said array to illuminate said package substantially simultaneously.
Claim 11
Dependent Claim
254 words
An adaptive lighting system for a machine vision apparatus for inspecting selected semiconductor packages, said system comprising: an array of plural light emitting elements divided into a plurality of segments of at least of one light emitting element per segment and disposed in a pattern for illuminating a semiconductor package to provide an image of said package suitable for inspection of said package; a camera disposed with respect to said array for recording an image of said package when said package is illuminated by said array; a light intensity control circuit operably coupled to said array for varying the intensity of light emitted by selected segments of said array to provide an image of said package having a predetermined contrast, said control circuit including plural potentiometers operably connected to respective ones of said segments of said array and operable to receive control signals from a processor for causing predetermined light intensities to be emitted by the light emitting elements of said segments, respectively; switch means interposed a selected one or more of said potentiometers and said light emitting diodes operably connected to said one or more potentiometers for switching output signals from said one or more potentiometers between selected ones of said segments to enable said camera to capture images of said package having respective different lighting imposed thereon; and a processor operably connected to said camera and said intensity control circuit for adjusting the light intensity emitted by said array to provide images of said package at respective different light intensities imposed thereon.
Claim 12
Dependent Claim
254 words
An adaptive lighting system for a machine vision apparatus for inspecting selected semiconductor packages, said system comprising: an array of plural light emitting elements divided into a plurality of segments of at least of one light emitting element per segment and disposed in a pattern for illuminating a semiconductor package to provide an image of said package suitable for inspection of said package; a camera disposed with respect to said array for recording an image of said package when said package is illuminated by said array; a light intensity control circuit operably coupled to said array for varying the intensity of light emitted by selected segments of said array to provide an image of said package having a predetermined contrast, said control circuit including plural potentiometers operably connected to respective ones of said segments of said array and operable to receive control signals from a processor for causing predetermined light intensities to be emitted by the light emitting elements of said segments, respectively; switch means interposed a selected one or more of said potentiometers and said light emitting diodes operably connected to said one or more potentiometers for switching output signals from said one or more potentiometers between selected ones of said segments to enable said camera to capture images of said package having respective different lighting imposed thereon; and a processor operably connected to said camera and said intensity control circuit for adjusting the light intensity emitted by said array to provide images of said package at respective different light intensities imposed thereon.
Claim 13
Dependent Claim
22 words
The system set forth in claim 9 wherein: said switch means comprise analog switches operably connected to respective ones of said potentiometers.
Claim 14
Dependent Claim
115 words
An adaptive lighting system for a machine vision apparatus, said system comprising: an array of plural optical fiber elements divided into a plurality of segments of at least optical fiber element per segment and disposed in a pattern for illuminating an article to provide an image of said article suitable for inspection thereof; a plurality of flash lamps disposed to transmit light from one end of said optical fiber elements, respectively, to the opposite end for illuminating said article; and a control circuit operably coupled to said flash lamps, respectively, for controlling light generated by said flash lamps and emitted by said optical fiber elements of said array to provide an image of said article.
Claim 15
Dependent Claim
115 words
An adaptive lighting system for a machine vision apparatus, said system comprising: an array of plural optical fiber elements divided into a plurality of segments of at least optical fiber element per segment and disposed in a pattern for illuminating an article to provide an image of said article suitable for inspection thereof; a plurality of flash lamps disposed to transmit light from one end of said optical fiber elements, respectively, to the opposite end for illuminating said article; and a control circuit operably coupled to said flash lamps, respectively, for controlling light generated by said flash lamps and emitted by said optical fiber elements of said array to provide an image of said article.
Claim 16
Dependent Claim
43 words
The system set forth in claim 11 including: a flash lamp driver and trigger circuit operably connected between respective ones of said flash lamps and said control circuit for operating said flash lamps in response to a signal generated by said control circuit.
Claim 17
Dependent Claim
36 words
The system set forth in claim 12 including: a control circuit for generating a flash lamp trigger signal for selectively energizing said flash lamps, respectively, at least one of momentarily and continuously at a predetermined frequency.
Claim 18
Independent Claim
246 words
A method for illuminating a semiconductor package for viewing by a machine vision apparatus wherein said machine vision apparatus includes a lighting array comprising a plurality of light emitting elements, a camera for recording an image of said package when illuminated by said array and a processor including a circuit for recording an image captured by said camera, a memory, a processor circuit and a lighting intensity control circuit for controlling the intensity of light emitted by at least selected ones of said light emitting elements to adjust the illumination of said package, said method comprising the steps of: (a) retrieving a set of light intensity values for selected ones of said lighting elements from a file in said processor corresponding to selected physical characteristics of said package; (b) illuminating first and second sets of light emitting elements of said array at respective predetermined intensities; (c) capturing an image of said package with said array illuminated at said predetermined intensities of said first and second sets of light emitting elements; (d) illuminating said first set of light emitting elements at the intensity settings of said second set of light emitting elements in step (b) and illuminating said second set of light emitting elements at the intensity settings of said first set of light emitting elements in step (b); (e) capturing an image of said package with said array illuminated as set forth in step (d); and (f) comparing the images captured in steps (c) and (e).
Claim 19
Independent Claim
246 words
A method for illuminating a semiconductor package for viewing by a machine vision apparatus wherein said machine vision apparatus includes a lighting array comprising a plurality of light emitting elements, a camera for recording an image of said package when illuminated by said array and a processor including a circuit for recording an image captured by said camera, a memory, a processor circuit and a lighting intensity control circuit for controlling the intensity of light emitted by at least selected ones of said light emitting elements to adjust the illumination of said package, said method comprising the steps of: (a) retrieving a set of light intensity values for selected ones of said lighting elements from a file in said processor corresponding to selected physical characteristics of said package; (b) illuminating first and second sets of light emitting elements of said array at respective predetermined intensities; (c) capturing an image of said package with said array illuminated at said predetermined intensities of said first and second sets of light emitting elements; (d) illuminating said first set of light emitting elements at the intensity settings of said second set of light emitting elements in step (b) and illuminating said second set of light emitting elements at the intensity settings of said first set of light emitting elements in step (b); (e) capturing an image of said package with said array illuminated as set forth in step (d); and (f) comparing the images captured in steps (c) and (e).
Claim 20
Independent Claim
216 words
A method for illuminating a semiconductor package for viewing by a machine vision apparatus wherein said machine vision apparatus includes a lighting array comprising a plurality of light emitting elements arranged in a predetermined pattern, said light emitting elements being divided into plural segments of said pattern, a camera for recording an image of said package when illuminated by said array in accordance with a preselected intensity of light emitted by selected ones of said segments and a processor including a circuit for recording an image captured by said camera, a memory, a processor circuit and a lighting intensity control circuit for controlling the intensity of light emitted by said selected ones of said light emitting elements, said method comprising the steps of: (a) identifying a package viewed by said camera by physical characteristics of said package; (b) illuminating said package with light emitting elements of a preselected number of segments of said lighting array; (c) capturing an image of said package with said camera while illuminated with said preselected number of segments; (d) from time to time illuminating said package with a number of segments of said lighting array greater than the number of segments illuminated in step (b); and (e) capturing an image of said package while illuminated with said greater number of segments.
Claim 21
Independent Claim
216 words
A method for illuminating a semiconductor package for viewing by a machine vision apparatus wherein said machine vision apparatus includes a lighting array comprising a plurality of light emitting elements arranged in a predetermined pattern, said light emitting elements being divided into plural segments of said pattern, a camera for recording an image of said package when illuminated by said array in accordance with a preselected intensity of light emitted by selected ones of said segments and a processor including a circuit for recording an image captured by said camera, a memory, a processor circuit and a lighting intensity control circuit for controlling the intensity of light emitted by said selected ones of said light emitting elements, said method comprising the steps of: (a) identifying a package viewed by said camera by physical characteristics of said package; (b) illuminating said package with light emitting elements of a preselected number of segments of said lighting array; (c) capturing an image of said package with said camera while illuminated with said preselected number of segments; (d) from time to time illuminating said package with a number of segments of said lighting array greater than the number of segments illuminated in step (b); and (e) capturing an image of said package while illuminated with said greater number of segments.
Claim 22
Dependent Claim
134 words
An adaptive lighting system for a machine vision apparatus comprising: an array of plural light emitting elements supported for projecting light on an article to be viewed; a camera for recording an image of said article when illuminated by said array; a light intensity control circuit operably coupled to said array including a plurality of potentiometers operably connected to respective selected segments of said array for controlling the intensity of light emitted by the light emitting elements of said segments, respectively, to adjust the illumination of said article viewed by said camera to obtain a predetermined image of said article; and a processor operably connected to said camera and to said intensity control circuit for adjusting the light intensity emitted by said array to provide said image of said article recorded by said camera.
Claim 23
Dependent Claim
134 words
An adaptive lighting system for a machine vision apparatus comprising: an array of plural light emitting elements supported for projecting light on an article to be viewed; a camera for recording an image of said article when illuminated by said array; a light intensity control circuit operably coupled to said array including a plurality of potentiometers operably connected to respective selected segments of said array for controlling the intensity of light emitted by the light emitting elements of said segments, respectively, to adjust the illumination of said article viewed by said camera to obtain a predetermined image of said article; and a processor operably connected to said camera and to said intensity control circuit for adjusting the light intensity emitted by said array to provide said image of said article recorded by said camera.
Claim 24
Dependent Claim
23 words
The system set forth in claim 16 wherein: said array of light emitting elements comprises an array of plural light emitting diodes (LEDs).
Claim 25
Dependent Claim
19 words
The system set forth in claim 17 wherein: said light emitting elements are disposed substantially uniformly about said article.
Claim 26
Dependent Claim
34 words
The system set forth in claim 17 including: a circuit including circuit elements operable to provide an output signal to cause all segments of said array to illuminate said article momentarily and substantially simultaneously.
Claim 27
Dependent Claim
30 words
The system set forth in claim 16 wherein: said array comprises plural rings of light emitting elements arranged concentrically on a support structure about an aperture in said support structure.
Claim 28
Dependent Claim
38 words
The system set forth in claim 16 wherein: said potentiometers comprise digital potentiometers operable to receive control signals from said processor for causing predetermined light intensities to be emitted by said light emitting elements of said segments, respectively.
Claim 29
Dependent Claim
23 words
The system set forth in claim 16 wherein: said control circuit includes constant current sources interconnected between said potentiometers and said segments, respectively.
Claim 30
Dependent Claim
32 words
The system set forth in claim 22 wherein: said constant current sources comprise, respectively, operational amplifiers in circuit with power MOSFETs and interposed said potentiometers and the lighting elements of said segments.
Claim 31
Dependent Claim
25 words
The system set forth in claim 16 including: switch means for switching output signals from said intensity control circuit between selected ones of said segments.
Claim 32
Dependent Claim
143 words
An adaptive lighting system for a machine vision apparatus comprising: an array of plural light emitting diodes (LEDs) supported for projecting light on an article to be viewed; a camera for recording an image of said article when illuminated by said array; a light intensity control circuit operably coupled to said array for varying the intensity of light emitted by selected segments of said array to adjust the illumination of said article viewed by said camera; a circuit including a potentiometer connected to a monostable multi-vibrator timing circuit operable to provide an output signal to cause all segments of said array to illuminate said article momentarily and substantially simultaneously; and a processor operably connected to said camera and to said intensity control circuit for adjusting the light intensity emitted by said array to provide an image of said article recorded by said camera.
Claim 33
Dependent Claim
143 words
An adaptive lighting system for a machine vision apparatus comprising: an array of plural light emitting diodes (LEDs) supported for projecting light on an article to be viewed; a camera for recording an image of said article when illuminated by said array; a light intensity control circuit operably coupled to said array for varying the intensity of light emitted by selected segments of said array to adjust the illumination of said article viewed by said camera; a circuit including a potentiometer connected to a monostable multi-vibrator timing circuit operable to provide an output signal to cause all segments of said array to illuminate said article momentarily and substantially simultaneously; and a processor operably connected to said camera and to said intensity control circuit for adjusting the light intensity emitted by said array to provide an image of said article recorded by said camera.
Claim 34
Dependent Claim
137 words
An adaptive lighting system for a machine vision apparatus comprising: an array of plural light emitting elements supported for projecting light on an article to be viewed; a camera for recording an image of said article when illuminated by said array; a light intensity control circuit operably coupled to said array for varying the intensity of light emitted by selected segments of said array to adjust the illumination of said article viewed by said camera; a processor operably connected to said camera and to said intensity control circuit for adjusting the light intensity emitted by said array to provide an image of said article recorded by said camera; and a light failure module operably connected to said system and operable to provide a signal indicating the failure of one or more light emitting elements of said array.
Claim 35
Dependent Claim
137 words
An adaptive lighting system for a machine vision apparatus comprising: an array of plural light emitting elements supported for projecting light on an article to be viewed; a camera for recording an image of said article when illuminated by said array; a light intensity control circuit operably coupled to said array for varying the intensity of light emitted by selected segments of said array to adjust the illumination of said article viewed by said camera; a processor operably connected to said camera and to said intensity control circuit for adjusting the light intensity emitted by said array to provide an image of said article recorded by said camera; and a light failure module operably connected to said system and operable to provide a signal indicating the failure of one or more light emitting elements of said array.
Claim 36
Dependent Claim
35 words
The system set forth in claim 26 wherein: said light failure module includes voltage comparator means for detecting an open circuit or reverse connection of said one or more light emitting elements of said array.
Claim 37
Dependent Claim
39 words
The system set forth in claim 27 wherein: said light failure modul includes voltage comparator means for comparing a reference voltage with a voltage at a power MOSFET operably coupled to each of said segments of light emitting elements.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-03-26 | 2004-09-25 | 2005-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-03-26 | 2008-09-25 | 2009-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-03-26 | 2012-09-25 | 2013-03-27 | $7700.00 | Window Closed / Lapsed |