Mirrors
Optical components - mirrors are intended for the following applications:
laser resonators;
systems of transforming and focusing of laser's beam.
Silicon is effectively used as the substrates for production of CO2 mirrors. Laser resonators can be formed in different designs but the cavity mirrors basically consist of a total reflector and an output coupler. The total reflectors are used as rear reflectors and fold mirrors and externally as beam benders in beam delivery systems.
We mainly offer plane, concave and convex elements. Circular, rectangle and ellipsoid configuration of the mirrors are realizable.
The reflectivity of such mirrors should be as high as possible for a laser wavelength. To meet above requirement Tydex provides some types of total reflecting coatings on the base of Au which allow to achieve more than 99.0% reflectance at 10.6 mm. Upon special inquiry above coatings can be optimized not only to provide high reflectance at 10.6 mm but to emphasize a definite wavelength at visible spectral range as well. Such coatings for the application discussed withstand power density to 1 kW/cm2 in CW mode and energy density to 1 J/cm2 for pulsed lasers.
For high power applications, since effective heat abstraction is needed, we provide drilled parts to ensure better cooling. The elements with internal blind thread holes as well as other complex reworks are also offered upon a certain inquiry.
Maximal available sizes of optical components are:
Si - 200 mm.
SILICON MIRRORS
Silicon is the most commonly used mirror substrate. Its advantages are low cost, good durability, and thermal stability. Low value of the coefficient of linear thermal expansion and its weak increasing with the temperature make Silicon key material for low power CO -lasers.
Specifications:
1.
Material:
monocrystalline Cz-Si
2.
Shape of the working surface:
plane, spherical
3.
Dimensional range (diagonal of optical part), mm:
to 200
4.
Clear aperture:
> 90% of a size
5.
Diameter (width & length) tolerances, mm:
+0.0 / -0.1
6.
Thickness tolerance, mm:
+/- 0.1
7.
Parallelism (concentricity)
plano & radiused, arc. min.:<= 5
8.
Surface quality, scr/dig:
for parts to 3 inches:
40/20
for larger parts:
60/40
9.
Surface figure (power-irregularity)
@ 633 nm:plano:
1 fringe - 1/2 fringe
radiused:
varies dependent upon radius
10.
Coating type & Reflectivity*
@ 10.6 mm, (AOI = 0 deg.):HR, protected Au, %:
99.0
HR, enhanced Au, %:
99.2
11.
Damage threshold:
CW mode, kW/cm2:
1
pulse mode, J/cm2:
1
* - upon special inquiry we can provide the reflectivity for VIS wavelengths as high as 85% while saving the above values for 10.6 µm wavelength.