Bauteile für Ho:YAG und Tm:YAG Laser

Ho :YAG and Tm :YAG lasers emitting at wavelengths of 2010 nm and 2100 nm are widely used for medical applications. LAYERTEC offers optical coatings for this wavelength range with high laser induced damage thresholds and long lifetimes.

Mirrors

a cavity and a pump mirrorFigure 1: Reflectance spectra of a cavity mirror (a) and a pump mirror (b) which has a region of high transmittance around 808 nm.
cavity mirror for 2010 nmFigure 2: Reflectance spectra of a cavity mirror for 2010 nm which supresses the 2100 nm line (a) and a turning mirror for 2100 nm (b)
  • HR cavity, pump and turning mirrors with R > 99.9% at AOI = 0° and at AOI = 45° for s - polarization, R > 99.8 % at AOI = 45° for p - polarized light
  • High laser induced damage thresholds

Output Couplers and Beamsplitters

output couplerFigure 3: Reflectance spectrum of an output coupler with R = 82 % at 2100 nm

Beam Splitters and Output Couplers with precisely adjusted degrees of Reflectivity:

ReflectanceTolerance
R > 95%± 0.5%
R = 80 ... 95 %± 1%
R = 10 % ... 80%± 2%

Thin Film Polarizers and Edge Filters

thin film polarizer for 2010 nmFigure 4: Reflectance spectra of a thin film polarizer for 2010 nm (Rs > 99.8 %, Rp < 2 %, AOI = 55°) (a) and a steep edge filter for the separation of the 2010 nm and 2100 nm lines (b)

Thin Film Polarizers

  • Separation of the s - and p-polarized component of the light (s-polarized light is reflected and p - polarized light is transmitted)
  • TFPs can be produced for AOI > 40°, but polarization is most efficient and appears in a broad wavelength range if AOI ≈ 55° (Brewster angle) is used