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7 Station extensions User Manual SIPLACE HF Series 7.7 Multicolor PCB camera (type 18) 21 Software Version S R.505.xx 05/2004 US E dition 320 – White lighting This type of illumina tion is u sed for standar d PCBs with t…

User Manual SIPLACE HF Series 7 Station extensions

Software Version SR.505.xx 05/2004 US Edition 7.7 Multicolor PCB camera (type 18) 21

319

7.7 Multicolor PCB camera (type 18) 21

7.7.1 General

As an option, a multicolor PCB camera can be installed in place of the sub-gantry camera. The

multicolor PCB camera offers four different types of illumination. This greatly increases fiducial de-

tection and thus the centering accuracy.

Fig. 7.7 - 1 Multi-color PCB camera

7.7.2 Type of illumination

The following types of illumination can be selected on the multicolor PCB camera:

– Standard lighting

This mixture of white and infrared lighting can be used to detect a broad range of fiducials. The

image contrast can be improved by varying the illumination, thus optimizing the centering of

different fiducials.

7 Station extensions User Manual SIPLACE HF Series

7.7 Multicolor PCB camera (type 18) 21 Software Version SR.505.xx 05/2004 US Edition

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– White lighting

This type of illumination is used for standard PCBs with tinned fiducials.

– Blue oblique lighting

In most cases, this can be used to greatly improve the contrast with bright fiducials on a light

base material, such as ceramic or CEM. Fiducials covered with solder resist can also be de-

tected better on a light background.

– Infrared lighting

This type of illumination is particularly useful for fiducials that are covered with solder resist or

for fiducials on flex materials. It is also sometimes possible to improve detection of silver/plat-

inum fiducials on ceramic. This should be tested by carrying out a test centering or placement

run.

User Manual SIPLACE HF Series 7 Station extensions

Software Version SR.505.xx 05/2004 US Edition 7.8 PCB alignment

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7.8 PCB alignment

7.8.1 General

PCBs to be processed sometimes have a length to width ratio of 1:2 or worse. This means that

the shorter side of the PCB points in the direction of travel. During travel, such PCBs may twist

slightly and, as a result, the fiducials no longer lie within the PCB vision camera's search window.

In this case, the "PCB alignment" option ensures that these PCBs are realigned precisely at the

stopping position.

If PCBs with recesses in the direction of travel are processed, this may result in different process-

ing positions on machines with mechanical stoppers (HS-50, S-25 HM, F5 HM) and on machines

that monitor this position with laser light barriers (HF, HS-60, S-27 HM). The "PCB alignment" op-

tion ensures that the PCBs are stopped at the same position on all PCB conveyors. The "PCB

alignment" option is available for both single and dual conveyors.

Fig. 7.8 - 1 PCB alignment

(1)Lifting table

(2)PCB stop