7.3.3 Laser Switching Time Compensation

In an ideal world, laser sources and galvanometer scanners would be able to react both instantaneously and simultaneously to command signals.

Unfortunately, in the real world, laser sources and scanners react at rather different rates - generally, a laser is much quicker off the mark than any scanner.^{[Note 1]}

Consequently, we need some means to adjust the time at which the laser source is commanded to switch on, relative to time at which the the scanners are commanded to start moving.

Making the laser wait for the scanners to start or stop moving.

To ensure uniform marking, the laser must not be switched on until the scanners have reached a predefined marking speed, and not switched off until the scanners have reached the last commanded position.

For this purpose the SP-ICE-3 Card implements the LaserOnDelay, and LaserOffDelay properties.

Laser Delays

The optimum values for the Laser On/Off Delays is application dependent.

Please refer to 7.3.3.1 Selecting Laser Delay Values for more details.

Notes

A few types of laser actually do react slower than scanners: large CO₂ sources, for instance.
In such cases, it is still possible to compensate for this by specifying negative Laser On/Off Delays.