Interference Bandpass Filters | UV–NIR Optical Filters

Bandpass Filter Description

Interference bandpass filters are precision optical components designed to selectively transmit a narrow wavelength band while blocking or reflecting unwanted wavelengths across the UV, visible, and near-infrared (NIR) spectrum. They are widely used in spectroscopy, fluorescence microscopy, machine vision, CCTV, biomedical imaging, ANPR, and optical sensing systems.

Shape Optics Technologies provides fast delivery and broad stock availability for hundreds of bandpass filter wavelength combinations. Our bandpass filters are constructed by combining longpass and shortpass thin-film interference coatings within a proprietary precision ring assembly, ensuring excellent spectral performance, mechanical stability, and repeatability.

All mounted interference bandpass filters are CNC-scribed and hermetically sealed, forming a robust multilayer stack that delivers long-term wavelength stability and environmental durability. In addition to mounted filters, unmounted bandpass filters with aerospace-grade blackened edges are available upon request to minimize stray light and improve system contrast.

Bandpass Filter Technical Specifications

Available Optical Performance

• FWHM (Bandwidth):

  • 30–80 nm, OD 2–3

  • 5–25 nm, OD 4–6

• Transmission: Typically 60–70% (higher transmission options available)
• Blocking Range: 200 nm to FIR (3000+ nm) with metal-dielectric blocking
• Cavity Design: 3–7 cavity interference structures

Mechanical Options

• Standard Sizes: Ø6 mm – Ø90 mm
• Custom Sizes: Available on request
• Mounting: Mounted (standard) or unmounted
• Edge Treatment: Aerospace blackened edges (optional)

Center Wavelength Range

• 340 – 1064 nm
• Common CWLs include 340, 365, 380, 405, 450, 492, 510, 546, 578, 600, 620, 630, 808, 850, 940, 1064 nm

Standard Bandpass Filter Product Range

Our stock range of high-quality visible and NIR bandpass filters covers 400 nm to 940 nm with multiple bandwidth options, supporting applications from ANPR imaging and CCTV to high-end surveillance and scientific instrumentation.

• Configurations: 25 mm diameter, 50 × 50 mm square

• Filter Types:

  • Standard Bandpass Filters

  • High-Transmission Bandpass Filters

  • UV Bandpass & Red-Rejection UV Filters

• Blocking Level: OD4 typical

• Spectral Stability: High angle and temperature stability options available

(Full CWL/FWHM/item number table retained as provided for technical reference and ordering.)

Applications of Optical Bandpass Filters

Optical bandpass filters are essential in applications requiring high spectral selectivity and signal-to-noise optimization, including:

• Fluorescence microscopy & life sciences
• Spectroscopy & analytical instruments
• Machine vision & industrial inspection
• Medical diagnostics & clinical chemistry
• Security, surveillance & imaging systems

Custom bandpass filters are available for prototype development, OEM integration, and high-volume manufacturing.