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SIPLACE 80S/F/G User’s Manual 7 Vision Systems Edition 07/97 from S oftware Version SR.010.xx 7.5 Teaching the Fiducial Line engi neer 7 - 51 Modification of existing fiducials In ever y teach pro cess the c entering off…

7 Vision Systems SIPLACE 80S/F/G User’s Manual

7.5 Teaching the Fiducial Edition 07/97 from Software Version SR.010.xx

7 - 50 Line engineer

Fig. 7.5.16

●

With the arrow keys you can vary the position of the camera. The increment can be specified by entering

the numbers 1 ... 6.

●

With the “>” and “<” signs you can shift the template window limits and teach simultaneously. Here you can

use the space bar to switch from the horizontal to the vertical direction. The field increments can be

changed from 1 pixel to 10 pixels and vice versa using the “TAB” key.

●

With “RETURN” the teach process is initiated.

The unique value is displayed on the screen as the measurement result. This can vary between

–

0 = inadequate and

–

100 = very good discrimination.

In our experience you should attain a minimum value of 60.

●

Run the teach process repeatedly with modified field variables. You can thereby optimize the unique value.

A reduction in the template window variable to dimensions which are smaller than the fiducial will increase

the unique value, since the fiducial ends will exhibit poor reflectivity when for example wetted with solder

resist. You should not, however, select too small a field as the clarity of the fiducial will also suffer as a

result.

●

With “ESC” you can quit this option.

NOTE

The relationship between uniqueness and quality factor for a fiducial is described in Section 7.5.3.2 Option

“New fiducial”.

Fiducial No. = 8 Uniqueness = 70

Blank: hor./vert.

< : smaller

Tab : field step

Template high res.

1..6 : x/y step

: x axis +

: x axis -

: y axis +

: y axis -

x/y step width = ...Direction = ...

Field step = ...

Ret: teach

> : larger

SIPLACE 80S/F/G User’s Manual 7 Vision Systems

Edition 07/97 from Software Version SR.010.xx 7.5 Teaching the Fiducial

Line engineer 7 - 51

Modification of existing fiducials

In every teach process the centering offsets are set to zero. If this is not done, optical centering with the tem-

plate limits will not be correct. The measurement result would be corrupted.

7.5.4.2 Option “Change search area”

The search area is a freely selectable field within the visual field of the camera.

@BOX = NOTE

— Select the size so that the search area still will not fail to take tolerances into account during board

positioning.

— Make sure also that there are no other structures within the search area as

otherwise fiducial reidentification will be made unnecessarily harder.

— Run the tests repeatedly using modified search area variables. You may be able to optimize the

unique value.

When the option “Change search area”is selected

–

the menu disappears.

–

the teach process is started.

–

the video image is displayed with fiducial and template window.

–

header and footer lines are displayed with commentary, measurement result, keyboard assignment and

command sequences.