Newport has introduced the manual UVA-800-M and motorised UVA-800-Conex, a set of variable attenuators designed to address the challenge of safely attenuating the output of ultrafast amplifiers.
The new ultrafast variable attenuators are composed of specially designed thin-film polarisers, zero-order achromatic waveplates and high-precision opto-mechanics, enclosed in shuttered housings.
The thin-film polarisers have a high damage threshold and are pre-aligned in the sealed housing to minimise exposure to dust and other contaminants.
These polarisers are utilised in conjunction with a half-waveplate, providing continuously adjustable intensity ratio splitting of the dual S- and P-polarised outputs.
The P-polarised output passes through the first polariser with negligible beam deviation and minimal dispersion.
The S-polarised output is reflected off two polarisers in a parallel offset of 1in from the fundamental, with negligible dispersion.
Both outputs have polarisation contrast ratios greater than 1:450 and require no adjustment over the entire working range.
For added functionality, the sealed housing includes a manual shutter for the S-polarised port and a removable beam dump on the P-polarised port.
The motorised version's rotational stage has an integrated Conex controller/driver, which is powered and communicates with a computer via USB port.
A free Nstruct applet to control the stage is available for download from Newport's website.