Neutral Density Filters (W-ND) - HOYA Optics Europe

World standard neutral density filters (W-ND filters) with top quality and excellent optical performance. The W-ND series is designed to match the world standard and is 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 (405 nm, 546 nm and 694 nm).
The specification of W-ND series is different from the conventional HOYA ND filters.

Applications: Cameras

Neutral Density Product Portfolio

	HOYA W-ND series	HOYA ND series
Standard Thickness	1.0 mm^*	2.5 mm^*
Transmittance	Specified at 405 nm, 546 nm, 694 nm as internal transmittance	Specified as average external transmittance from 400 nm to 700 nm

*The optical characteristics of W-ND/ND series filters are always adjusted by controlling the thickness of the glass.

Item	Standard Value			Colour specification (Standard illuminants A)		Thickness	Refractive Index	Chemical properties		Thermal properties			Mechanical properties		Specific gravity
	τ405nm	τ546nm	τ694nm	x	y	mm	600 nm	DW	DA	Tg	Ts	α 100/300	HK	FA	d
W-ND9	0.025±0.01	0.04±0.02	0.08±0.02	0.463	0.404	1.00	1.521	3	2	490	545	78	415	109	2.46
W-ND3	0.06±0.02	0.10±0.02	0.17±0.03	0.454	0.404	1.00	1.516	3	2	485	545	75	416	114	2.44
W-ND4	0.27±0.03	0.31±0.03	0.39±0.04	0.445	0.405	1.00	1.508	3	2	490	555	70	417	111	2.42
W-ND5	0.56±0.03	0.57±0.03	0.62±0.03	0.446	0.408	1.00	1.506	3	2	490	560	68	416	124	2.42
W-ND11	0.76±0.02	0.77±0.02	0.79±0.02	0.446	0.408	1.00	1.504	3	2	485	565	66	423	110	2.40

The listed data are standard values. As we are always improving our products, the data listed are subject to change without notice.