Scanlab RTC 5 PC Interface Board, Инструкция по установке и эксплуатации

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RTC
®
5 PC Interface Board
Rev. 1.9 e
7 Basic Functions for Scan Head and Laser Control
104
innovators for industry
Variable Polygon Delay
A variable polygon delay mode can be activated via
the command
set_delay_mode or
set_delay_mode_list . In this mode, the RTC
®
5
allows varying the length of the polygon delay,
depending on the angle

between the two
successive marking vectors – see figure 34 .
For each corner of the polyline, the RTC
®
5 calculates
the variable polygon delay v_delay (

) as follows:
v_delay (

) = scale (

)
·
polygon_delay ,
where scale (

) is a scaling function (0

scale (

)

2).
The parameter polygon_delay is set by the command
set_scanner_delays .
Figure 34 (bottom) shows the default scaling
function.
This standard curve can be replaced by a customized
curve. See
"Customizing the Variable Polygon Delay"
on page 106 .
Edgelevel
Figure 34 shows that the variable polygon delay
becomes quite long if the angle

is close to 180°.
This might lead to burn-in effects in the sharp corners
of the polyline. To avoid this, the user can define a
so-called
edgelevel
: If the polygon delay between
two mark or arc commands is longer than or equal to
this value, the RTC
®
5 turns the laser off after the first
mark or arc command upon reaching the
edgelevel
(after inserting a LaserOff delay) and starts a new
polyline at the beginning of the next mark or arc
command. Also see
figure 35 on page 105 . Before
the laser is switched on, the polygon delay will also
(if required) be extended until the LaserOff delay has
completely finished.
For further details see set_delay_mode , page 415 .
Edgelevel
Average delay, defined
by set_scanner_delays
Maximum
34
Variable Polygon Delay
Top: Definition of the angle

Bottom: Variation of the polygon delay (default curve)
f
2
f
1
ff
180° 90° 0°
0
scale (
f
)
1
2
1 – cos (
f
)
Angle

between the
vectors of a
polygon