Bandpass Lens Filter 660 nm, Select your size, 660 nm peak wavelength, useful range between 630-690 nm, useful range FWHM: 60 (±5 nm)

The Bandpass Lens Filter 660 nm is a lens filter designed to pass light with a peak wavelength of 660 nm and a useful range between 630–690 nm, while blocking all other wavelengths.

It mounts directly onto a standard machine vision lens using the built-in filter thread.

With a broad selection of thread sizes, the BP660 can be matched securely to a wide variety of lenses, ensuring stable optical performance in demanding machine vision environments.

Overview of the BP660 Narrow Bandpass Filter

Narrow bandpass filters function by transmitting only a defined portion of the light spectrum while blocking all other wavelengths. 

For the BP660, transmission exceeds 90% at the 660 nm peak, and stays above 80% throughout the 630–690 nm useful range, corresponding to a 60 nm FWHM (±5 nm). This narrower passband delivers precise spectral isolation for wavelength-critical imaging tasks.

Specification
Filter type	Narrow Bandpass
Peak wavelength	660 nm
Peak wavelength color	Red
Useful wavelength range	630-690 nm

Available Thread Sizes for the BP660 Lens Filter

Because lenses come in different sizes, the BP660 filter is available in several standard thread options, making it suitable for both compact and larger lenses.

• C-mount filter

• 0.5 thread (pitch): M22.5×0.5, M25.5×0.5, M27×0.5, M30.5×0.5, M34×0.5, M35.5×0.5, M37×0.5, M37.5×0.5, M40.5×0.5

• 0.75 thread (pitch): M37×0.75, M43×0.75, M46×0.75, M49×0.75, M52×0.75, M55×0.75, M58×0.75, M60×0.75, M62×0.75, M67×0.75, M72×0.75

Using the BP660 with a C-mount (CMT) Filter Thread

If you intend to use a C-mount filter thread, just fill out the form below to get instant access to the manual on how to mount it and see which lenses it’s compatible with!

Bandpass Lens Filter 660 nm Applications

The BP660 is optimized for imaging centered at 660 nm, delivering high spectral selectivity that improves contrast and measurement repeatability.

For monochrome cameras, the filter acts as a red-selective element, passing only the desired red wavelength region while blocking neighboring and complementary wavelengths. This follows a subtractive color-filtering principle, emphasizing red tones while reducing interference from other colors.

Used with a white or broadband illumination source, the BP660 isolates a clean 660 nm band and provides:

• stronger contrast

• improved distinction of fine surface features

• reduced sensitivity to ambient light

• consistent, repeatable image quality

These characteristics make it an excellent choice for machine vision inspection, color-based sorting, and precision optical measurement.

Applications for a 660 nm Bandpass Lens Filter

• Red / deep-red LED or laser illumination

• Surface defect detection

• Fluorescence or color-based inspection

• Red-spectrum color enhancement and contrast analysis

Adding the BP660 Filter to Your Machine Vision Setup

Most machine vision lenses include a front-mounted filter thread, allowing the BP660 filter to be attached directly.

If you are using a C-mount lens on a GigE camera or USB3 camera, the filter can also be placed inside the C-mount connection instead of on the front of the lens.

This option is particularly useful when the lens lacks a front filter thread.  

Positioning the filter between the camera and lens keeps it fixed in the optical path, maintaining optical alignment and stable imaging performance.  

These flexible installation options make the BP660 easy to incorporate into existing setups without modifying your current camera or lens configuration.

660 nm Bandpass Filter: Advantages

• • High transmission at the 660 nm center wavelength
  • Strong blocking of wavelengths outside the target band
  • Enhanced contrast and cleaner signal output
  • Stable optical behavior across variable conditions
  • Reliable, repeatable performance for high-precision imaging tasks

Find the BP660 Filter Best Suited to Your Optical Setup

Select the BP660 narrow bandpass lens filter in the thread size that fits your lens. For assistance choosing the right size or wavelength, contact our technical team.