Circular Variable Neutral Density Filters (CVND)
Circular Variable Filters (UV-VIS-IR) are filter wheels that linearly attenuate light as the filter is rotated. As the filter rotates, the beam intensity is customized due to the density variation of a gradient metallic coating around the filter. These filters are fully customizable in optical density gradient function, transmission gradient function, substrate type, coating materials, and size to meet customer requirements. Densities can be supplied as a standard linear or a customized gradient function.
Custom sizes and densities are available upon request.
Specification & Models:
| Part Number | Substrate Material | Outer Diameter | Inner Diameter | Optical Density |
|---|---|---|---|---|
| R00500-xx | BK-7 | 25mm | 7.5mm | Specify |
| R00510-xx | BK-7 | 50mm | 7.5mm | Specify |
| R00515-xx | BK-7 | 75mm | 7.5mm | Specify |
| R00520-xx | BK-7 | 100mm | 7.5mm | Specify |
| R00522-xx | BK-7 | 100mm | 25.4mm | Specify |
| R00525-xx | BK-7 | 125mm | 25.4mm | Specify |
| R00530-xx | BK-7 | 150mm | 25.4mm | Specify |
| R00550-xx | BK-7 | 175mm | 25.4mm | Specify |
| R00580-xx | BK-7 | 200mm | 25.4mm | Specify |
| R04400-xx | Fused Silica | 25mm | 7.5mm | Specify |
| R04410-xx | Fused Silica | 50mm | 7.5mm | Specify |
| R04415-xx | Fused Silica | 75mm | 7.5mm | Specify |
| R04420-xx | Fused Silica | 100mm | 7.5mm | Specify |
| R04422-xx | Fused Silica | 100mm | 25.4mm | Specify |
| R04425-xx | Fused Silica | 125mm | 25.4mm | Specify |
| R04430-xx | Fused Silica | 150mm | 25.4mm | Specify |
| R04450-xx | Fused Silica | 175mm | 25.4mm | Specify |
| R04465-xx | Fused Silica | 200mm | 25.4mm | Specify |
| R05600-xx | ZnSe | 25mm | 7.5mm | Specify |
| R05610-xx | ZnSe | 50mm | 7.5mm | Specify |
| R05620-xx | ZnSe | 100mm | 7.5mm | Specify |
| R00520-xx | ZnSe | 100mm | 7.5mm | Specify |
Specifications:
- Coating Types: Metallic
- Anti-Reflection Coating: Available
- Substrate Materials: BK-7, Fused Silica and ZnSe
- Outside Diameter (OD): 25mm – 200mm ± 0.2mm
- OD Tolerance: ± 5% Absolute
- Inside Diameter: 7.5mm – 25.4mm ± 0.2mm
- Thickness: 2.0mm ± 0.2mm
- Optical Density Range: Specify: 0 to 1, 2, 3, 4, or 5
- Wavelength Calibration: BK-7: 510nm, F.S: 510nm, ZnSe: 2.5µm
- Wavelength Range: BK-7: 375nm – 2500nm, F.S: 200nm – 2500nm, ZnSe: 2.0µm – 5.0µm
- Gradient Range: 270° Typical
- Parallelism: < 3 Arc Minutes
- TWE: < 2 Waves per 25mm
- Centration: ± 0.2mm
- Surface Quality: 80/50 Scratch & Dig
- Clear Aperture: 80% of Diameter
