Long Pass Filters

Hard dielectric edge filters
Ultra steep slopes, high transmission in the passband, and up to OD6 blocking — all achieved with durable thin-film dielectric coatings. Each filter is custom-designed to meet your exact performance requirements.
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Two circular long pass optical filters — one upright showing a deep royal blue interference coating, and one lying flat with a soft lavender hue, both in unmounted form.

Key Features

Up to OD6+ blocking
Fully custom designs
Made to order
Hard dielectric thin film coatings
Durable Quadrode™ plasma PVD technology
Ultra steep slopes
Up to 95% average transmission
Available mounted or unmounted
Spectral transmission chart for a 500 nm long pass filter, showing near-zero blocking below 500 nm followed by an ultra-steep cutoff edge and approximately 97% transmission maintained from 500 to 1600 nm across the full measured range.

Technical Specifications

PARAMETER
SPECIFICATION
Spectral edge
310–1800 nm standard
Blocking
Up to OD6+
Transmission
Up to 95% average
Slope
<1%
Coating Type
Hard dielectric coatings utilizing Quadrode™ plasma PVD technology
Substrate Materials
Borofloat, Fused Silica, BK7, Custom
Surface Quality
60-40 scratch-dig
Clear Aperture
>85% of diameter on mounted parts
Configuration
Mounted or unmounted
Custom spectral edge / Sizing
Available on request
Environmental
Please contact for full environmental specifications

Request a Quote

Contact our team for pricing, custom specifications, and lead times.

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