Colored Glass Filters

COLORED GLASS FILTERS

Neutral Density Filters (W-ND)

World standard Neutral density filters (W-ND filters) with top quality and excellent optical performance. W-ND series is designed to match the world standard and different from current line of neutral density glass types in terms of thickness and transmittance.
Neutral density filters can be used for various purposes including adjustment of light amount as the light intensity can be controlled without selectively absorbing light with a specific wavelength (405nm, 546nm and 694nm).
Specification of W-ND series are different from the conventional HOYA ND filters.

Application: Camera

Neutral Density Product Portfolio

HOYA W-ND series HOYA ND series
Standard Thickness t1.0mm* t2.5mm*
Transmittance Specified at 405nm, 546nm, 694nm
Internal Transmittance		 Average 400-700nm
External Transmittance

*Optical characteristics of W-ND/ND series filters are always made by adjusting thickness of the glass.

Transmittance (Internal Transmittance)

Transmittance (Internal Transmittance): Data

ItemStandard ValueColor specification
(Standard illuminants A)		ThicknessRefractive IndexChemical propertyThermal propertiesMechanical propertiesSpecific gravity
τ405nmτ546nmτ694nmxymm600nmDWDATgTsα
100/300		HKFAd
pdfW-ND90.025±0.010.04±0.020.08±0.020.4630.4041.001.52132490545784151092.46
pdfW-ND30.06±0.020.10±0.020.17±0.030.4540.4041.001.51632485545754161142.44
pdfW-ND40.27±0.030.31±0.030.39±0.040.4450.4051.001.50832490555704171112.42
pdfW-ND50.56±0.030.57±0.030.62±0.030.4460.4081.001.50632490560684161242.42
pdfW-ND110.76±0.020.77±0.020.79±0.020.4460.4081.001.50432485565664231102.40