Components for the second harmonics of Nd:YAG and Nd:YVO4 Lasers

The harmonics of Nd:YAG and Nd:YVO4 lasers are widely used for materials processing as well as for measurement applications. Moreover, the second harmonic of the Nd:YAG laser is often used as pump source for Ti:Sapphire lasers. On these pages we introduce optics for 532 nm: dual wavelength mirrors, separators, thin film polarizers and non-polarizing beamsplitters, but also cavity optics for compact diode pumped lasers of different configurations. All designs are calculated according to customer specification.

Dual wavelength cavity mirrorFigure 1: Reflectance spectra of a dual wavelength cavity mirror with high transmittance for the pump wavelength (808 nm) (a) and a dual wavelength turning mirror (b)
Separators for the second harmonic from the ground wavelengthFigure 2: Reflectance spectra of separators for the second harmonic from the ground wavelength:
(a): HR(0°, 1064 nm) > 99.9 % + R(0°, 532 + 808nm) < 3 %
(b): HRs+p(45°, 532 nm) > 99.9 % + Rs+p(45°, 808 + 1064 nm) < 2 %
Thin film polarizerFigure 3: Reflectance spectra of a thin film polarizer (a) and of a non-polarizing beamsplitter (b) for 532 nm with Rs=Rp = 50 ± 2 % (|Rs - Rp| < 3 %)

Separator for the third harmonic and the second harmonicFigure 4: Reflectance spectra of separator for the third harmonic from the second harmonic and the ground wave (a) and of a dual wavelength turning mirror for 355 nm and 532 nm (b)

The transmission of thin film polarizers for p-polarized light can be measured with high accuracy by a modified cavity ring down setup.
HR mirror for 1064nmFigure 5: Reflectance spectrum of a HR mirror for 1064nm which is also an output coupler for 532 nm: HR(0°, 1064 nm) > 99.9 % + R(0°, 532 nm) = 99 %

For common specifications of separators for the harmonics in the UV spectral range please see the table on our site higher-harmonics. Do not hesitate to contact us for separators or mirrors with other angles of incidence.

Coatings on Nonlinear Optical Crystals

HR mirror for 1064nmFigure 6: Reflectance spectrum of a dual antireflection coating on KTP for 532 nm and 1064 nm

Nonlinear optical crystals are the key elements for frequency conversion. LAYERTEC offers a variety of coatings on crystals like KTP and lithium niobate.