Metallic ND Filter, UV Fused Silica, 50.8x50.8 mm, 2.0 OD at 632.8 nm

The FSQ-ND20 UV Fused Silica Metallic Neutral Density Filter is a 50.8 x 50.8 mm square UV fused silica metallic ND filter with an optical density of 2.0 at 632.8 nm. Our metallic neutral density coatings provide broadband attenuation for lower power applications. The coating is deposited on one side of an ultra-pure UV grade fused silica substrate providing excellent transmission from the UV to near-infrared. All filters are permanently marked with the optical density.

Specifications

Technical Specs

Size
50.8 x 50.8 mm
Wavelength Range
350 - 2000 nm
Optical Density
2
Optical Density Tolerance
±4% @ 632.8 nm
Transmission
1.0% @ 632.8 nm
Angle of Incidence
0°
Material
UV grade fused silica or equivalent
Damage Threshold
30 W/cm² CW, typical; not recommended for pulsed laser use
Thickness
3.0 mm
Thickness Tolerance
±0.25 mm

Surface Flatness
≤2λ at 632.8 nm over the clear aperture
Surface Quality
60-40 scratch-dig
Clear Aperture
≥central 80% of dimensions
Wedge
≤3 arc min
Chamfers
0.25–0.76 mm face width
Chamfers Angle Tolerance
45° ±15°
Durability
MIL-C-48497A, adhesion, humidity, moderate abrasion, and solubility requirements
Cleaning
See How to Clean Optics

Size
50.8 x 50.8 mm
Wavelength Range
350 - 2000 nm
Optical Density
2
Optical Density Tolerance
±4% @ 632.8 nm
Transmission
1.0% @ 632.8 nm
Angle of Incidence
0°
Material
UV grade fused silica or equivalent
Damage Threshold
30 W/cm² CW, typical; not recommended for pulsed laser use
Thickness
3.0 mm
Thickness Tolerance
±0.25 mm

Surface Flatness
≤2λ at 632.8 nm over the clear aperture
Surface Quality
60-40 scratch-dig
Clear Aperture
≥central 80% of dimensions
Wedge
≤3 arc min
Chamfers
0.25–0.76 mm face width
Chamfers Angle Tolerance
45° ±15°
Durability
MIL-C-48497A, adhesion, humidity, moderate abrasion, and solubility requirements
Cleaning
See How to Clean Optics

Resources & Downloads

Drawings And Cad

COLOREDG-S(61 kB, PDF)

Other

FSQ-ND20 RoHS Certificate(264.7 kB, PDF)
FSQ-ND20_ROHS2-2021.pdf(280.5 kB, PDF)

Related Products

Frequently Purchased Together

Description	Compatibility	Price
FSQ-ND10Metallic ND Filter, UV Fused Silica, 50.8x50.8 mm, 1.0 OD at 632.8 nm	UNIVERSAL	$158
FSQ-ND05Metallic ND Filter, UV Fused Silica, 50.8x50.8 mm, 0.5 OD at 632.8 nm	UNIVERSAL	$158
FSQ-ND30Metallic ND Filter, UV Fused Silica, 50.8x50.8 mm, 3.0 OD at 632.8 nm	UNIVERSAL	$165
FSQ-ND03Metallic ND Filter, UV Fused Silica, 50.8x50.8 mm, 0.3 OD at 632.8 nm	UNIVERSAL	$158

Similar

Description	Compatibility	Price
FBR-ND20ND Filter, Metallic, Optical Crown Glass, 25.4 mm, 2.0 OD at 632.8 nm	UNIVERSAL	$59
5242Neutral Density Filter, 2.0 Optical Density, 1.0 in. Diameter	UNIVERSAL	$46
FBS-ND20ND Filter, Metallic, Optical Crown Glass, 50.8 x 50.8 mm, 2.0 OD	UNIVERSAL	$74
NDIR10-20Neutral Density Filter, Infrared, 25 mm, 2.0 OD, ±0.25% Tolerance	UNIVERSAL	$530
FRQ-ND20Metallic ND Filter, UV Fused Silica, 25.4 mm, 2.0 OD at 632.8 nm	UNIVERSAL	$71

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Description	Compatibility	Price
M-PPL17Thick Optical Filter Holder, Thumbscrew Clamp, Up To 12 mm Thick	UNIVERSAL	$151
FH-2SOptical Filter Holder, Drop-in, 50.8 mm Optics	UNIVERSAL	$103
CYM-2RCylindrical Lens Mount, Adjustable, 50.8 mm Max, +/- 5 Deg., 2 arcs sec	UNIVERSAL	$211