Germanium Components

IntroductionGermanium components
Ge components can be fabricated in diameters from 3.0mm up to 250mm; in thicknesses from 1mm
upwards, and in the form of lenses, flats, prisms and rectangular windows. Relatively few
components are treated as standard types (in comparison with ZnSe products).
The Ge components which are stocked are mainly laser spares for some well-known brands of pulsed
CO2 laser marking systems.
Germanium components may be custom-made for applications such as thermal imaging systems and
fire-detector systems.
Tolerances/specifications
All material used is high specification optical grade Ge, with resistivity 5-40 ohm cm. For
components up to 50.8mm diameter the Ge is monocrystalline.
Unless made to special order and otherwise specified by the customer, ULO Optics work to the
following standard specifications…

Lenses
Diameter : +0 / -0.1mm
Thickness : ± 0.1mm
Surface form : Spherical within λ/80 over 25 dia test area
Focal length : EFL within 0.5% of specified value
Surface roughness : <2 nm RMS
Centration : < 0.05mm ETV
Flats
Flatness : Within λ/20 per 50mm dia test area
(Etalons within λ/160, @10.6μm)
Parallelism : Within 3 arcminutes
(Etalons within 2 arcseconds)
Coatings
Standard available coatings include:
* Laser AR/AR for 10.0μm
* Environmentally durable AR/AR for 10.6μm
* Broad-band AR/AR for 3-5μm
* Broad-band AR/AR for 8-12μm
* Wide-band AR/AR for 3-12μm
* Partial reflectors AR/PR
Available products
See technical data section 35.00 for details of Ge optical spares for Laser Applications (now
Lumonics Hull) laser systems.
See technical data section 36.00 for details of Ge optical spares for Cryophysics (now Imaje) laser
systems.
See technical data section 47.00 for details of Ge optical spares for Alltec GmbH laser systems.