Synrad FH FLYER 3D - Beam Expansion;Path Length

appendix c
Beam expansion/path length
Each SYNRAD laser family (48 Series, Evolution, and Firestar) has slightly dierent beam diameter and
divergence values. The standard FH mounting scheme, consisting of our L-bracket and Mounting Rail, takes
these issues into account by (1) the xed mounting distance between the laser and the marking head and
(2) the beam expander/telescope installed in the FH head. The beam expander’s expansion ratio is selected
to match the laser’s beam diameter and divergence characteristics so that beam diameter at the focusing
optic is approximately 10–11 mm. For 48 Series and Firestar f100 lasers with a beam diameter of 3.5 mm
and a divergence of 4 milliradians (mrad), the expansion ratio is 3X; Evolution lasers (4 mm / 3.5 mrad)
require a 2.5X expander; and Firestar v-Series and t-Series lasers (2 mm / 7 mrad) require a 5X expander.
In situations where the FH Flyer marking head is mounted “remotely” on a non-standard mount, the beam
path may not exceed certain distances as illustrated in Figures C-5–C-7, otherwise the laser beam will
overow the input aperture optic, potentially damaging the head. Each illustration shows the maximum
path length for a given laser family in two situations: (1) where the beam expander is mounted in the
marking head (the standard expander location) and (2) in situations where the expander is mounted in a
user-designed custom mount at the faceplate of the laser (custom expander location).
Important Note: Because the resulting optical beam path is much longer in a non-standard mounting
scheme, the working distance of the lens will dier from the distance measured dur-
ing the marking head’s nal test evaluation. You should use the value indicated in
the marking head’s Final Test Report as a starting point to determine the new work-
ing distance. Non-standard FH mounting also aects the focused spot size, causing
the spot diameter to vary slightly from standard values. Because of this variation, the
performance of your marking head will dier from results obtained during sample
testing and will not meet the published specications given in Tables 5-1 and 5-22.
In addition, the longer beam path and resulting change in focal length aects the
overall eld size of the lens. You may need to optimize FieldScaleX and FieldScaleY
values to obtain the correct dimensions when marking objects with critical values.
Although path length can be greatly increased by designing a custom expander mount attached to the
laser faceplate, alignment of the FH marking head to the laser becomes much more complex. The user-
designed custom expander must be mounted perfectly collinear to the laser beam and must allow adjust-
ment in both axes so that the expander can be aligned with the beam. In addition, the expanded beam
becomes dicult to view and center in the alignment target. Keep in mind that an FH Field Alignment
Kit, SYNRAD part number 230-18176-01, is required in all instances where the FH marking head is not
mounted to the standard L-bracket/Mounting Rail assembly and remember that mounting attachments for
the laser, marking head, and any intermediate optics must allow for ne adjustment in all axes.
Note: The FH Field Alignment Kit (shown in Figure C-4) does not provide the ability to make actual
hardware alignment adjustments. The kit only provides the means to determine the true beam
path, thus indicating the direction in which hardware adjustments must be made.
Field Alignment Instructions
Screw Set
FH Field Alignment
Instructions
Expander Removal Tool
Alignment Fixture
Beam Alignment Tool
Figure C-4 FH Field Alignment Kit
SYNRAD FH Series Flyer Operator’s Manual Version 3.4
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