Scanlab RTC6 PCIe Board Installation And Operation Manual page 171

Notes
• As of RTC6 Software Package V1.12.0, you can
leave the focus length value l in RTC6 20-bit
range [–524,288...+524,287], if you use
load_z_table_20b / load_z_table_no_20b
read_abc_from_file_20b
write_abc_to_file_20b.
• ABC values from the *_ReadMe.txt file of
correction file are to be interpreted as
16-bit values.
Procedure
• Refer also to the "Calibrating a 3-Axis Laser Scan
System" Manual.
• See also Notes, page 171.
(1) Adjust the correct mechanical distance between
the scan system and the z = 0 working plane and
the correct distance between the
varioSCAN device and the scan system
(2) Load the 3D correction file by
load_correction_file.
(3) Assign the 3D correction table by
select_cor_table.
(4) Read out the assigned coefficients A, B and C by
get_head_para.
(5) varioSCAN FC and intelliWELD FC only: proceed
with step 10. Steps 6...9
performed.
(6) Move the laser spot to the reference point
goto_xyz.
(7) Set the z axis to the neutral (middle) position by
load_z_table_20b(0, 0, 0).
(8) Place a test object at the reference point.
(9) Adjust the laser focus, see
(10)Move the focus to an arbitrary point (x|y|z)
within the (required) 3D Image Field
(3)
goto_xyz .
(1) See the corresponding manual.
(2) The reference point is a point in the z = 0 working
plane for which a middle focus length value is required
for a sharp laser focus. The laser beam should be
focused to the reference point when the z axis is set to
the neutral position (Z output value z
coordinate values of the reference point (in mm) are
provided in the *_ReadMe.txt file that accompanies the
3D correction file or in the 3-axis scan system's or the
varioSCAN user manual. If you are using an F-Theta
objective, the reference point is generally the origin
(0|0|0).
RTC6 boards
Doc. Rev. 1.0.21 en-US
7 Basic Functions for Scan Head Control and Laser Control
and
/
(1)
.
do not need to be
(2)
by
page 170.
by
= 0). The
out
(11)Query the focus length value l (in RTC6-20-bit
range [–524,288...+524,287]) set by the
RTC6 PCIe Board for this point
get_z_distance.
(12)Optimize the laser focus at this point:
vary the Z output value z
laser focus meets your requirements
load_z_table_20b(A=z
A starting value can be calculated in accordance
2
with A + Bl +Cl by using the previously read
focus length value l and the previously read or
used values A, B and C.
(13)Repeat steps 10...12 for as many locations
(6)
(x|y|z) as possible and write down the values
(l|z ) for each new point. If possible, seek to
out
thereby cover the entire
by your application.
(14)Fit the function z = A + Bl +Cl
out
to your value pairs (l|z
(15)Use the resulting coefficients A, B and C to adjust
the 3D correction table by load_z_table_20b(A,
B, C).
Values loaded by load_z_table_20b
by a subsequent load_correction_file
(load_correction_file sets the three coefficients A, B
and C to the values of the loaded correction table).
load_correction_file
After each
you should therefore also call
load_z_table_20b(A, B, C) again.
By load_z_table_no_20b, the three coefficients
A, B, C can be assigned to correction table No. They are
switched with select_cor_table.
Alternatively, the ABC values can be written
permanently to the header of the correction file by
write_abc_to_file_20b, see also parameter
Section "ct5 Correction File Header", page
(3) If you are using a scan system with an F-Theta
objective, it is sufficient to select various points (0|0|z)
on the z coordinate axis. The maximum possible
3D Image Field is specified in the corresponding user
manual.
(4) The focus length value l can be positive or negative,
see notes on get_z_distance.
(5) The optimal z output value can be positive or
out
negative.
(6) Note that larger z control values lead to shorter
working distances and that the focus thereby shifts
toward the scan system. The test object might have to
be tracked accordingly.
(4)
by
until the quality of the
out
(5)
by
, 0, 0).
out
3D Image Field required
2
).
out
are overwritten
or select_cor_table,
5...7 in
178.
171