Neutral Density Filters
Neutral density that is actually neutral — absorptive glass and calibrated coated ND for imaging, sensing and instrument programs.
Neutral, Across the Band
A good ND filter attenuates without tinting: optical density held flat across the working band, within the tolerance your color or radiometric budget demands. We build both lanes — absorptive ND glass (nickel-based neutral glass for broad visible bands) and coated ND on clear substrate (flat density through visible or specified IR bands) — because tint behavior, not density number, is what ruins an imaging program.
Densities from OD0.1 fine-trim pieces through OD3 sensor-protection levels, in round and square formats. Stepped ND sets (e.g. OD 0.3/0.6/1.0/2.0 kits) are assembled and serialized on request for instrument programs that issue filters as calibrated accessories.
Graduated and Solar Effect Grades
The graduated ND family — soft and hard edge gradients, reverse and sunset gradates — is produced on the same coating line that runs our photographic special-effect series, so retail programs buy graduated ND alongside black mist and wire-drawing filters on one PO. Density grades for solar observation sit in the family too (see the solar and moon filter page for safe solar grades).
Calibration and Data
Bulk production carries measured density curves with the lot; calibrated serial pieces (density marked per piece with certificate) are a stated add-on, not an assumption. For lidar and active-sensing programs, ND plus bandpass hybrids are one design, not two stacked parts — tell us the signal and sun budget.
Frequently Asked Questions
Absorptive or coated ND?
Absorptive glass stays neutral over wide bands and wide angles at modest cost; coated ND reaches higher densities, tighter tolerances and IR bands. The color budget decides.
Do you mark density per piece?
As a calibration service: pieces measured, marked and certificated on request. Standard production ships lot-measured curves instead.
ND for lidar sensors?
Yes — ND+bandpass hybrids matched to 905/1550 nm programs with sun-load handling discussed up front.
Photographic set packaging?
Retail-ready ND sets with cases, pouches, blister and peg-box options from the same lines that build our consumer filter series.
Related Pages
Custom Bandpass Filters
Interference bandpass filters to your CWL and half-band: 450/532/660/850/940 nm sensing lines, astronomy bands
Dichroic Filters & Beamsplitters
Longpass, shortpass and beamsplitting dichroic filters for fluorescence, projection, vision and illumination p
Black Mist & Creative Effect Filters
Black mist, soft-focus and creative effect glass filters for photography brands — wholesale tiers, retail-read
Wire-Drawing & Star Filters
6/12-point star, wire-drawing and streak filters for photography and stage — custom point counts and grades, w
Solar & Moon Astronomy Filters
Safe-grade solar filters (stark film and coated glass), full-aperture and telecope-mounted formats, plus moon
Aspherical Lenses
Aspheric lens production: molded glass and plastic aspheres plus polished aspheric surfaces for imaging, laser
Achromatic Doublets & Objectives
Cemented achromatic doublets, telescope objectives and coated lens assemblies — BK7/SF pairing, AR coated, mea
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Coating design proposals, tolerance advice and tiered pricing, from the engineers who run the coater.