Scanning Lenses, MSL/2/15xxx Series

Introduction2 element lens
The MSL/2/15.. series of scanner lenses are 2-element designs, for CO2 laser beams up to 15mm
diameter, supplied complete in a mechanical housing.
These lenses give excellent F-theta performance, with resolution (focused spot size) at, or very
close to the diffraction limit over a flat image plane. Variation of spot size (standard deviation from
average spot size over the full scanned field) is minimal.
Performance is optimized for mirror locations appropriate to the use of 15mm full beam diameter.
Suitable scanner mirrors are:-MSM-1-1630 plus MSM-2-3330.
A full range of standard focal lengths, from 75mm to 300mm, is available.
Technical Specifications
Construction : 1 ZnSe element, 1 Ge element, In black-anodised aluminium housing.
Input clear aperture : 48mm diameter, all models.
Transmission : 97% typically.
Coatings : AR coated for 10.6μm, all surfaces.
Diameter : See table 10.221 and fig. 10.222.
Length : See table 10.221 and fig. 10.222.
Mounting : M65 x 1 male thread, 6mm long.
Design S1 value : 17.1mm.

double element data

Notes on table 10.221
(1) WD is stated for the optimum image plane, and refers to the rear mounting flange as reference
(2) Spot sizes are stated for a 15mm diameter TEM00 beam, and refer to 1/e2 intensity points.
(3) Field sizes correspond to nominal beam scan angle of ±20°.
(4) Stated focal length is actual value, (not a nominal figure).


Mirror locations
See figure 10.222.
Suitable scanner mirrors are:
MSM-1-1630 plus
Material, coatings and
Only full-specification optical
materials are used in
MSL/2/15/xxx series lenses.
All surfaces are polished to
better than 1/100th wave
spherical accuracy and
1/400th wave ovality as determined
over the specified
beam diameter, at 10.6μm.



Surface roughness is better than 2nm (RMS). Element centration to better than 0.05mm ETV.
The lenses are anti-reflection coated with

[laser specification] ultra-low absorption thin films giving
a reflectivity of <0.25% per surface (ZnSe) and <0.5% per surface (Ge).
Custom-made products
For special applications demanding high environmental durability, the Ge front lens can be treated
with a high-durability AR/AR coating. This will reduce optical transmission, but increase lifetime
in moist environments.
Multi-element scanner lenses for other beam diameters, and of other focal lengths, can be designed
and built. Please call to discuss.