Neutral Density Filter

Specifications Neutral density filters attenuate,split or combine beams in a range of irradiance ratios with little dependence on wavelength.

The thickness of neutral grey glass type filter deermin the transmission,however,transmission is determined by coating thickness in the metallic coated optical material type. Typical diameter is phi 10.0mm,15.0mm,20.0mm,25.4mm,other size a shape of quadrate,triangular,or other polygonals are available upon request.

Attribute	Specification
	Neutral Density Glass Type	Metallic Coating Type
Material	Optical Neutral Density Glass	Bk7,Fused Silica
Typical Size(mm)	Φ25.0, 50.0*50.0	Φ25.0*2.0, 50.0*50.0*2.0
Size Tolerance(mm)	±0.2
Parallelism	3arc min.
Flatness(per25mm@633nm)	2λ(General), λ/2(High Precision)
Surface Quality	80/50(General),20/10(High Precision)
Optical Density	0.04,0.1,0.2,0.3,0.4,0.5, 0.8,1.0,2.0,3.0,4.0,etc	0.1,0.2,0.3,0.5,0.8,1.0, 2.0,3.0,4.0,etc.
Optical Density Tolerance	±5%