Digital feature separation

• US 20020006219A1
• Filed: 03/09/2001
• Published: 01/17/2002
• Est. Priority Date: 03/10/2000
• Status: Active Grant

• Current Assignee: Infotech AG
• Original Assignee: Infotech AG
• Inventors: Hudson, Edison T.
• Granted Patent: US 6,557,251 B2
• Time in Patent Office: Days
• US Class Current: 382/153
• CPC Class Codes: H01L 21/67144 Apparatus for mounting on conductive members, e.g. leadframes or conductors on insulating substrates
• CPC Class Codes: H01L 21/67271 Sorting devices
• CPC Class Codes: H05K 13/0053 Arrangements for assisting the manual mounting of components, e.g. special tables or light spots indicating the place for mounting
• CPC Class Codes: H05K 13/0812 the monitoring devices being integrated in the mounting machine, e.g. for monitoring components, leads, component placement
• CPC Class Codes: Y10T 29/49131 by utilizing optical sighting device
• CPC Class Codes: Y10T 29/49769 Using optical instrument [excludes mere human eyeballing]
• CPC Class Codes: Y10T 29/49778 with aligning, guiding, or instruction
• CPC Class Codes: Y10T 29/53087 with signal, scale, illuminator, or optical viewer
• CPC Class Codes: Y10T 29/53174 Means to fasten electrical component to wiring board, base, or substrate

Abstract

A semiautomatic method for digital feature separation uses a trained sample selected by an operator using a software “eye dropper” tool or a similar region-of-interest tool to sample features of interest on a stored digital image of, for example, an electronic component such as pads, bumps or leads of the component. Pixels from the sampled features are analyzed and plotted based on their color hue and saturation values or gray scale intensity values. The range of such values is chosen by a user. A second digital image is then compared to the sampled feature data gathered by the “eye dropper” tool. If the color and intensity values of the pixels from the second digital image fall within a user defined acceptable absolute value range, then the locations and values of those pixels in the image are saved. Background or surrounding elements in the second digital image which do not fall within the acceptable value range are deleted and replaced with a code that makes these background or surrounding element locations appear as a graphic transparency. This process leaves only the features of interest in their original locations saved in the graphics memory surrounded by pixels that have been made video transparent. The resulting saved image which contains only the selected features is then laid over a live image such as that of a target substrate with corresponding features of interest. The operator then manually aligns the saved features from the component image over the corresponding features of the live image of the substrate to achieve component to substrate registration.

Claims

1. A method for placing a component on a selected location of a substrate with a placement machine including at least an X-motion stage and a Z-motion stage including a pick-up head for carrying the component to the selected location on the substrate, said method comprising:

capturing a first digital image of the bottom of the component;

selecting a region of interest in the first digital image;

selecting a repetitive feature contained within the region of interest;

creating a template image showing the repetitive feature with background matter rendered transparent;

capturing a live image of the selected location of the substrate;

overlaying the live image and the template image to form a composite image on a video display;

manipulating the relative position in non-vertical directions of the component and the substrate until the repetitive feature is brought into alignment with corresponding repetitive features in the composite image; and

bringing the component into contact with the substrate by moving it in the vertical direction.

2. A method in accordance with claim 1 wherein said first digital image is a gray scale image and said creating includes analyzing said repetitive feature for intensity over a spatial range and identifying all similar repetitive features within the region of interest and rendering all other material in the template image transparent.

3. A method in accordance with claim 1 wherein said first digital image is a color image and said creating includes analyzing said repetitive feature for hue and saturation over a spatial range and identifying all similar repetitive features within the region of interest and rendering all other material in the template image transparent.

4. A method for placing a component on a selected location of a substrate with a placement machine including an X-Y motion stage and a Z-motion stage having a pickup head for carrying the component to the selected location on the substrate, the pick-up head being carried by the X-Y motion stage, said method comprising:

capturing a first digital image of the bottom of the component;

selecting a region of interest in the first digital image;

selecting a repetitive feature contained within the region of interest;

creating a template image showing the repetitive feature with background matter rendered transparent;

capturing a live image of the selected location of the substrate;

overlaying the live image and the template image to form a composite image on a video display;

manipulating the relative position in non-vertical directions of the component and the substrate until the repetitive feature is brought into alignment with corresponding repetitive features in the composite image; and

bringing the component into contact with the substrate by moving it in the vertical direction.

5. A method in accordance with claim 4 wherein said first digital image is a gray scale image and said creating includes analyzing said repetitive feature for intensity over a spatial range and identifying all similar repetitive features within the region of interest and rendering all other material in the template image transparent.

6. A method in accordance with claim 4 wherein said first digital image is a color image and said creating includes analyzing said repetitive feature for hue and saturation over a spatial range and identifying all similar repetitive features within the region of interest and rendering all other material in the template image transparent.

7. An apparatus for placing a component on a selected location of a substrate including a placement machine having at least an X-motion stage and a Z-motion stage with a pick-up head for carrying the component to the selected location on the substrate, said apparatus comprising:

means for capturing a first digital image of the bottom of the component;

means for selecting a region of interest in the first digital image;

means for selecting a repetitive feature contained within the region of interest;

means for creating a template image showing the repetitive feature with background matter rendered transparent;

means for capturing a live image of the selected location of the substrate;

means for overlaying the live image and the template image to form a composite image on a video display;

means for manipulating the relative position in non-vertical directions of the component and the substrate until the repetitive feature is brought into alignment with corresponding repetitive features in the composite image; and

means for bringing the component into contact with the substrate by moving it in the vertical direction.

8. An apparatus in accordance with claim 7 wherein said first digital image is a gray scale image and said means for creating includes means for analyzing said repetitive feature for intensity over a spatial range and means for identifying all similar repetitive features within the region of interest and rendering all other material in the template image transparent.

9. An apparatus in accordance with claim 7 wherein said first digital image is a color image and said means for creating includes means for analyzing said repetitive feature for hue and saturation over a spatial range and means for identifying all similar repetitive features within the region of interest and rendering all other material in the template image transparent.

10. An apparatus for placing a component on a selected location of a substrate including a placement machine having an X-Y motion stage and a Z-motion stage with a pick-up head for carrying the component to the selected location on the substrate, the pick-up head be ing carrie d by the X-Y motion stage, said apparatus comprising:

means for capturing a first digital image of the bottom of the component;

means for selecting a region of interest in the first digital image;

means for selecting a repetitive feature contained within the region of interest;

means for creating a template image showing the repetitive feature with background matter rendered transparent;

means for capturing a live image of the selected location of the substrate;

means for overlaying the live image and the template image to form a composite image on a video display;

means for manipulating the relative position in non-vertical directions of the component and the substrate until the repetitive feature is brought into alignment with corresponding repetitive features in the composite image; and

means for bringing the component into contact with the substrate by moving it in the vertical direction.

11. An apparatus in accordance with claim 10 wherein said first digital image is a gray scale image and said means for creating includes means for analyzing said repetitive feature for intensity over a spatial range and means for identifying all similar repetitive features within the region of interest and rendering all other material in the template image transparent.

12. An apparatus in accordance with claim 10 wherein said first digital image is a color image and said means for creating includes means for analyzing said repetitive feature for hue and saturation over a spatial range and means for identifying all similar repetitive features within the region of interest and rendering all other material in the template image transparent.