NDW40B Dia. 25 mm Reflective ND Filter; Optical Density 4.0
- Type
- Filter
- Subtype
- Neutral Density Filter
- Brand
- Thorlabs
Properties
- Shape
- Circular
- Diameter
- 25 mm
Material
- Name
- N-BK7
- Dispersion Equation
- Sellmeier
- n (λ)
- 1.5150823520020043
- λ
- 633 nm
- B1
- 1.03961212
- C1
- 0.00600069867 μm2
- B2
- 0.231792344
- C2
- 0.0200179144 μm2
- B3
- 1.01046945
- C3
- 103.560653 μm2
NDW40B Dia. 25 mm Reflective ND Filter; Optical Density 4.0
The NDW40B is a Neutral Density Filter with a diameter of 25 mm, manufactured by Thorlabs. This filter is designed to reduce the intensity of incident light without altering its color composition, making it an essential tool for various optical applications.
The filter is made of N-BK7 Schott, a high-quality optical glass known for its excellent transmittance and low auto-fluorescence. It has a thickness of 1 mm, providing sufficient durability while maintaining minimal optical path differences.
The NDW40B boasts a high Optical Density of 4.0 at a wavelength of 633 nm. This means it can attenuate light by a factor of 10000, making it suitable for high-intensity light sources or sensitive detectors.
The filter features a Thin Lens shape, which minimizes edge effects and ensures uniform attenuation across the entire aperture. Both the front and back surfaces are coated with the THo NDW40B coating, enhancing its light reduction capabilities and providing excellent spectral uniformity.
The NDW40B is currently in stock and available for purchase through the Thorlabs website. For more information, please refer to the provided weblink.
