Catalogs >
MICRO-CONTROLE / Spectra-Physics >
Linear Variable Metallic Neutral Density Filters

Linear Variable Metallic Neutral Density Filters
1Pages

Catalog excerpts

Linear Variable Metallic Neutral Density Filters - 1

O p t i c s 569 Email: sales@newport.com • Web: newport.com WINDOWS BEAMSPLITTERS OPTICAL FILTERS POLARIZATION OPTICS DIFFRACTION GRATINGS HIGH-ENERGY OPTICS ULTRAFAST LASER OPTICS ACCESSORIES Linear Variable Metallic Neutral Density Filters These ND filters provide linearly varying attenuation or beamsplitting in the visible and NIR region. Attenuation is achieved by a thin film of aluminum protected with an overcoat, and variable beamsplitting is an added benefit of the inherent reflectivity of aluminum. The BK 7 or UV fused silica substrates have a slight wedge between the faces to eliminate unwanted fringe patterns and cavity feedback, and the rear surface is also antireflection coated for the broadband visible range. • Linear variable attenuator • Linear variable beamsplitter • Visible to NIR • Individual filters, or matched pairs to eliminate the density gradient over larger apertures Specifications Material BK 7, grade A, fine annealed optical glass or equivalent; UV grade fused silica Surface Flatness Specification below at 632.8 nm over the clear aperture Clear Aperture central 90% of length and 80% of width Dimensions 79.4 x 25.4 mm +0/-0.25 mm Thickness 3.18 +0/-0.76 mm Wedge 15 ±5 arc min in 25.4 mm dimension Matched Pairs 20 arc sec wedge mismatch Chamfers 0.25–0.76 mm face width x 45° ±15° Optical Density at 632.8 nm 0.08–2.0 ±5%, transmission along 25.4 mm dimension uniform to 5% Linearity of Density ±5% Coating, S1 Aluminum with an AR.14 overcoat Coating, S2 AR.14 broadband antireflection coating, Ravg <0.5% 430-700 nm at 0-15° AOI Durability Metalized area MIL-M-13508C, AR coated area MIL-C-675, moderate abrasion Cleaning Non-abrasive method, acetone or isopropyl alcohol on lens tissue recommended (see page 622) Damage Threshold 75 W/cm2 CW, 10 mJ/cm2 with 10 nsec pulses at 1064 nm, typical Ordering Information Model Material Optical Density Range Surface Flatness Surface Quality (scratch-dig) Individual Filters 31W00ML.1 BK 7 0.08–2.0 2ë 40-20 31Y02ML.1 UV Fused Silica 0.08–2.0 1ë 20-10 Matched Filter Pairs 31W00MP-ML.1 BK 7 0.16–4.0 2ë 40-20 31Y02MP-ML.1 UV Fused Silica 0.16–4.0 1ë 20-10 925B Compensated Attenuators include a matched pair of these filters, providing high resolution intensity control without introducing a gradient in the intensity distribution (see page 503). 79.4 3.18 25.4 S2 S1 15 ARC MIN WEDGE METALLIC COATING 66.7

Open the catalog to page 1