First version
Rev 1.00
22 Sep 2016
Helios User Manual
11
Chapter 4 – Check before Use
Be sure to check the laser parameters before turning it on to ensure no damage to Helios. Specifically, the power,
beam size, and exposure time must be within the specifications. (Use
to easily find the power density
from laser power and beam size.)
Preliminary test
Here’s a sample test to be sure everything is operating as it should:
(1)
Setup the Helios. (See section 3.)
(2)
Cover test:
a.
Open and close the cover, then open again.
(3)
Measurement test prep:
a.
Select the desired energy scale. The selection should be greater or equal to the maximum energy
expected.
b.
Set “current power” in options menu, to see the instantaneous power.
c.
Set laser parameters to below 50% damage for the first test.
d.
Check that status is “Ready” (not “Wait” or “Integrating”)
(4)
Measurement test:
a.
Fire laser.
b.
Confirm reasonable power in “current power” screen.
c.
Wait for energy results. (Status will be “integrating” until the results come in.)
d.
Read power, energy, and exposure time. Confirm these are reasonable, too.
Timing Considerations
There are a few criteria to consider when setting up a measurement timing scheme:
•
Each pulse or “shot” of the laser must of course be within spec (under 10 kJ, as well as within the maximum
power, time range, and damage threshold; see section 2).
•
Wait at least 12 seconds between shots.
•
When the Helios reaches 60 °C it must be left to cool down, which typically takes 10-20 minutes. (This
temperature is reached after about 40 kJ of accumulated exposure.)
Recommended beam sizes and exposure times for various laser powers can be found in the specifications table
(Chapter 2).
Temperature Failsafe
The Helios should not be used when the housing temperature exceeds 60 °C. To ensure this is always the case, there
is a bit (when using Profinet) and a command (when using RS232) that measures the current temperature and checks it
against the maximum temperature (60 degrees).
It is the responsibility of the customer software integrator to include a condition in the laser control that automatically
shuts off the laser if the temperature is exceeded.