Manual Variable Attenuator, Ultrafast, 690 - 1040 nm

Newport's VA-BB series of broadband ultrafast variable attenuators provide continuous attenuation over a series of broad wavelength ranges. The VA-BB series is designed to provide high attenuation of linearly polarized fundamental and harmonic frequencies of light for most ultrafast oscillators. The VA-BB series is available in manual or motorized versions. The motorized version can be used in open- or closed-loop operation.
The VA-BB series is based on zero-order half-waveplates and Glan-laser polarizers. For more detail on the principle of operation of these devices, please refer to Newport’s Application Note 26 – Variable Attenuator for Lasers. These attenuators are designed to handle average powers up to 100 Watts for wavelength ranges of 400 – 700 nm, 690 – 1040 nm, 650 - 1350 nm or 1000 – 1600 nm.
The optics and high-precision opto-mechanics are incorporated into a compact housing, flexibly designed for post mounting at varying optical axis heights. P-polarized light is transmitted with minimal loss collinear to the input beam path while S-polarized light is rejected into a beam dump on the side of the housing. M-4 and 8-32 mounting threads are included on the bottom and one side of the housing. This allows for horizontally or vertically polarized output.
The manual versions of the VA-BB series come with a manual rotary stage containing the half-waveplate. The user manually rotates the stage to control attenuation.