Smart Gui - Algorithm Training Material_rev1.pdf - 第303页

Copyright © ViT rox All Rights Reserved . Steps for Fiducial Setup 9. Back ground re f er s to the a verag e gr a yscale le vel in betw een " T emplate" and Out er Radius. Normally this area should be dark and …

Steps for Fiducial Setup

1. Ensure correct Fiducial Shape is selected. In this case, Ellipse should be chosen.

2. Normally a fiducial is brighter compared to the PCB/Background.

3. Ensure that appropriate size is set for Search Area which is in yellow colour. Search Area should be big

enough to cover Template and Inner & Outer Radius. Search Area is normally set as a square and should

not cover any bright area/pad of similar size to the actual fiducial.

4. Template should be slightly bigger than the actual fiducial, but smaller than “search Area”. It's in green

colour.

5. View Offset should normally be turned off (set to 0).

6. Inner DC means to exclude the “dirty” area residing inside the inner part of the fiducials. It should only be

applied when the dirty area in the inner part of the fiducial creates a significant impact on the total score

of the “Current Inspection Value”. It should be set smaller than the actual fiducial.

7. Inner Radius should be set slightly smaller than the actual size of the fiducial, on the bright area/pad.

8. Outer Radius should be set slightly bigger than the actual size of the fiducial, on the dark area/PCB. The

difference between Inner Radius and Outer Radius is normally 30-50.

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Steps for Fiducial Setup

9. Background refers to the average grayscale level in between " Template" and Outer Radius. Normally this

area should be dark and thus it should be set between 50-100.

10. Middle refers to the average grayscale level in between "Outer Radius" and "inner Radius". Normally this

area should consist of dark and bright area and thus it should be set in between 100-200.

11. Foreground refers to the average grayscale level inside the "Inner Radius". In case if "Inner DC" is used,

then foreground refers to the average grayscale level in between the inner radius and inner DC. Normally

this area is bright, thus it should be set in between 200-250.

12. Inspect and observe the value obtained in Current Inspection Value. The above parameter should be set

appropriately in order to get the highest score for "Current Inspection Value".

13. Current Inspection Value, ensure that an appropriate Presence Threshold is set. Presence threshold

should not be set too loose (typically 700).

14. Custom Lighting custom_#no.txt stores the lighting setting information. User may change the lighting

configuration in the file.

15. Alternate fiducial can be set when necessary (eg. When there is different fiducial sizes or shapes)

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Grayscale Editor

Grayscale Editor help users in setting the threshold that related to grayscale. User can find

this icon beside the threshold setting that related to grayscale.

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