Round Thin Film Laser Polarizers

  • Provide the achievement of strictly linear polarization of laser radiaton
  • Utilize the polarization wich occurs on reflection from a plane surface
  • Rs/Tp:>99.5/95.0% for standard thin film polarizers
  • Rs/Tp:>99.5/99.0% for high transmittance thin film laser polarizers
  • Ts<0.2%, Rp<0.2% for ultra high transmission thin film polarizers
  • Tp>98%, Ts<0.1% for thin film polarizers with high extinction ratio
  • High damage threshold reaching 10 J/cm2
  • Extinction ratio 200:1 (for standard, high and ultra high transmission thin film polarizers), 1000:1 (for thin film laser  polarizers with high extinction ratio)

Thin Film Laser Polarizers separate the s- and p-polarization components. They are designed for use in high energy lasers. Due to high damage threshold, reaching 10 J/cm2 @ 1064 nm 8 ns, Thin Film Polarizers are used as an alternative to Glan Laser Polarizing Prisms or Cube Polarizing Beamsplitters.

Typical applications are intracavity Q-switch hold-off polarizer or extracavity attenuator for Nd:YAG lasers.

Thin Film Polarizers can be used at an > 40° angle of incidence, but polarization is most efficient and appears in a broad wavelength range at 56° AOI (Brewster angle). Typical polarization ratio Tp/Ts is 200:1.

Standard size is up to Ø50 mm (2”), while max. available dimensions are 100×200 mm. For optimal transmission a Thin Film Polarizer should be mounted in an appropriate holder for angular adjustment. For Rectangular Thin Film Polarizers, visit here.

This article comes from eksma edit released

Intracavity PPLN crystals for ultra-low-voltage laser Q-switching and high-efficiency wavelength conversion

We report to the best of our knowledge the lowest switching voltage in an electro-optically Q-switched Nd:YVO4 laser by using a 13-mm long, 14-μm-period PPLN crystal as a Pockels cell. A switching voltage as low as ∼50 V in the PPLN crystal was sufficient to hold off the lasing of the Q-switched laser at a pump power more than two times above its continuous-wave threshold. When the PPLN Q-switch was driven by a 100-V voltage at 6.5 kHz, we obtained 0.9-kW laser peak power from this 1-W diode-pumped Nd:YVO4 laser system with 13% output coupling. When the PPLN Pockels cell was cascaded with a 5-cm long, 30-μm-period PPLN crystal, we produced ∼μJ/pulse energy at 1.59 μm from optical parametric generation inside the actively Q-switched laser.

This article comes from springer edit released

General properties of CdWO4 scintillator

Cadmium Tungstate (CdWO4) is a scintillation crystal with extremely low afterglow, good radiation resistance, high density and high Z value, low decay time also with relatively high light output.

CdWO4 scintillators was produced by using the Bridgman technique since 2011, with the maximum crystal boule size at ∅ 80 mm x 200 mm, which can be manufactured into the target sizes, besides the single crystals, we also have the capability to fabricate it into linear or 2 dimensional array used in the X ray security inspection systems.

CdWO4 scintillators is characterized by high density, high atomic number and relatively high light yield with extremely low decay time. and the afterglow of CdWO4, when subjected to x-ray irradiation, is very slow typically less than 0.1% after 3 ms, and demonstrate very good resistance. All of these features are significant and make CdWO4 a primary scintillation crystal for X ray computed Tomography(X-CT) and in security inspection.

This article comes from epic-crystal edit released