Neutral density filters (ND filters) are optical components designed to reduce light intensity without altering spectral characteristics. They are widely used in optical systems, laser attenuation, imaging, and laboratory applications where precise light control is required. Our ND filter collection includes absorptive neutral density filters made from optical gray glass, providing stable and uniform attenuation across multiple spectral ranges. Available products cover: Ultraviolet (UV) Visible (VIS, 400–700 nm) Near Infrared (NIR) Different material types are used to achieve optimal performance across these wavelength ranges.

Available Spectral Ranges

Our ND filters are available for multiple wavelength applications:

• UV Range: ~200–400 nm (quartz / fused silica based)
• Visible Range: 400–700 nm (standard gray optical glass)
• Near Infrared (NIR): 700–1100 nm+

Custom wavelength ranges are available depending on material selection and application requirements.

How to Choose an ND Filter

By Optical Density (OD)
OD0.04 – OD1 → Light attenuation and imaging adjustment
OD1 – OD3 → General optical control
OD3+ → High attenuation for laser and precision systems

By Transmission (%)
50% – 90% → Low attenuation
1% – 10% → Medium attenuation
<1% → High attenuation

By Shape & Size
Round filters → Standard optical mounts (e.g., 12.7 mm, 25.4 mm, 50 mm)
Square filters → Laboratory and flexible setups (e.g., 50 × 50 mm)

About ND Filters

ND filters reduce light intensity by absorbing a portion of the incident beam while maintaining a neutral spectral profile. This ensures that optical signals and images remain unchanged except for brightness.

Absorptive ND filters use gray optical glass or quartz materials depending on wavelength range, offering:

• Stable attenuation performance
• Low surface reflection

• Broad spectral usability

Optical Density vs Transmission

Optical density (OD) and transmission (T) describe attenuation:

• OD = log₁₀(1/T)
• OD1 → 10% transmission
• OD2 → 1% transmission
• OD3 → 0.1% transmission

Higher OD values correspond to stronger attenuation. 

Custom ND Filters

We provide custom solutions based on application requirements:

• Custom sizes and geometries
• Specific OD or transmission values
• UV, visible, or IR wavelength optimization
• Optical coatings (AR, reflective ND)

Contact us for customized optical solutions.