Bauteile für Rubin und Alexandrit Laser

Coatings for Laser Applications

Ruby and Alexandrite Lasers are especially used for medical laser applications and work at 694nm and 755nm, respectively. LAYERTEC offers a wide range of laser optics for both wavelengths with high laser induced damage thresholds and long lifetimes.

Besides typical combinations with wavelengths for the alignment of the optical system (e.g. 694nm + 633nm) a special feature of LAYERTEC products are the variety of combinations with other common wavelengths used for medical applications in the same device, but from different laser sources (e.g. 532nm + 694nm).

Cavity Mirrors

  • Reflectivity: R > 99.8...R > 99.9% at AOI = 0° using evaporation and sputtering
  • High damage thresholds (800 MW/cm2, 35ns pulse length)
Cavity mirror for 694nm and 755nmFigure 1: Reflectance spectra of cavity mirrors for 694nm (a) and 755nm (b)

Turning Mirrors

  • Reflectivity: R > 99.5% at AOI = 45° for random polarized light
  • Integrated pilot laser beam alignment (e.g. at 630 – 650nm)
  • High damage thresholds (800 MW / cm2, 35 ns pulse length)
Turning mirror for 694nm withFigure 2: Reflectance spectra of a turning mirror for 694nm in combination with a pilot laser at 633nm (unpolarized light)

Beam Combiners

  • Precisely adjusted degree of reflectivity by using sputtering technology
  • Integrated pilot laser beam alignment (e.g. at 635nm)
  • High performance and cost-optimized solutions with special designs
Special beam combiners for 694nm and 633nmFigure 3: Reflectance spectra of special beam combiners for 694nm and 633nm:
a) PRr(45°,694nm) = 99.0% + Rr(45°,633nm) < 35%
b) Rr(45°,630–640nm) > 35% + Rp(45°,694nm) < 0.3%

Output Couplers and Lenses

  • Output couplers with precisely adjusted degree of reflectivity
  • AR coatings with residual reflectivities R < 0.2% on the rear side of output couplers as well as on both sides of lenses and windows made of fused silica
AR coatings for 694nm and 755nmFigure 4: Reflectance spectra of AR coatings for 694nm and 755nm: a) AR(0°,694nm) < 0.2%, b) AR(0°–30°, 755nm) < 0.5%