TAU Tilt-Adjust Unit
Model TAU25 tilt-adjust unit is a rugged mechanical assembly giving the laser user fine control over
the orientation of a lens assembly (such as a beam expander) relative to the incoming laser beam.
This may be critical in the case of certain units with a high degree of inherent centration accuracy,
such as the BEZ10 and BEZ12 zoom beamexpanders.
TAU25 has a 38mm clear aperture, and is intended for use with a wide range of CO2 lasers of up to
25mm 1/e2 diameter.
The free-rotating (standard) coupling ring at the input end has a 52mm dia. x 1.5mm pitch female
thread, allowing attachment to OPG piping. The output end has a 52mm dia. male thread allowing
attachment of any module with a ‘xxx/25’ series standard coupling ring.
Dimensions : See Figure 72.81.
Construction : Aluminium alloy, black anodised.
Stainless steel tilt-adjust screws.
Clear aperture : 38.0 mm diameter.
Operation : By manual rotation tilt screws (3 off).
Fittings : Input … 52.0 x 1.5 pitch F/M thread.
Output … 52.0 x 1.5 pitch male thread.
Max diameter : 75.0mm
Tilt sensitivity : Better than ±12 arcseconds when using tommy bar 76mm (3″) long.
At the input end, model LAU25 may be connected to:
OPG piping …. section 61.
LAM25 lateral adjustment unit …. section 72.2.
Any adaptor/user-supplied equipment with a male thread 52.0 dia. x 1.5 pitch x 10mm length.
At the output end, the LAU25 accepts:
SBE series beamexpanders ….. section 67.2.
BE25 series beamexpanders ….. section 67.3.
MBE series beamexpanders ….. section 67.7.
BEZ12 zoom beamexpander ….. section 24.1.
BEZ10 zoom beamexpander …..section 24.3.
The importance of correct beam alignment when using zoom beamexpanders is described in detail
in technical data section 24.0 under the heading ‘Alignment Errors’.
If the incoming beam is not correctly aligned, then beam-wander must occur during actuation of the