HOYA Neutral Density Filters

Absorptive HOYA ®glass Neutral Density (nd) filters are used to control the intensity of light. The filters are stackable without resulting in multiple reflections. The HOYA nd glass absorbs the light within the filter. Each glass type is polished to a specific thickness and measured to produce the exact optical density and transmission. Custom or standard optical density's and transmission can be produced to individual wavelengths.

MATERIAL:

HOYA ®Filter Glass

SURFACE QUALITY:

Ø12.5mm≤ 3 fringes

DIAMETER TOLERANCE:

+0.0 / -0.2mm

SURFACE QUALITY:

Ø25.0mm≤ 5 fringes

SQUARE TOLERANCE:

± 0.2mm

SURFACE QUALITY:

Ø50.0mm≤ 8 fringes

THICKNESS TOLERANCE:

± 0.2mm

PARALLELISM:

≤ 3 arc minutes

SURFACE QUALITY:

60/40

EDGES:

fine ground