BBP-650 Broad Bandpass Filter
BBP-650 isolates the red channel with ~92–95 % transmission across ~620–700 nm and near-baseline leakage across the rest of the visible—built for high-contrast red illumination.
- Main passband (T): ~92–95 % T @ 620 – 700 nm
- Cut-on / cut-off: Steep edges near ~610 nm and ~710 nm
- Out-of-band (VIS): ~0–2 % T across ~420 – 600 nm and ~720 – 800 nm
- UV/blue feature: ~20–30 % T @ 370 – 410 nm (optional extra blocking)
- Ghost control: Optional rear AR and slight wedge available
- Substrates: Borofloat®, Eagle XG, D263 T (≤ 450 °C), soda-lime (≤ 150 °C)
- Size / thickness: 5 – 450 mm • 0.21 – 3.8 mm (custom cut & dicing)
Learn more
BBP-650 is a red visible bandpass centred near 650 nm, delivering
~92–95 % transmission across ~620–700 nm with steep edges for clean separation
from neighbouring colours. Outside the main window, transmission stays near baseline
(~0–2 %) across much of the visible, reducing background and improving contrast under
broadband illumination.
Note: the spectrum can show a secondary transmission feature in the near-UV/blue around
~370–410 nm (up to ~20–30 % transmission). If your source or detector is sensitive
there, KUPO can add an additional blocking stack to suppress this feature fully.
Typical uses: 650 nm LED inspection lighting, red emission isolation in fluorescence
and bio-imaging, red-channel separation in multispectral systems, reflectance/absorption photometry,
and stray-light control in optical instruments. KUPO supplies rear-surface AR, slight wedge, and
rapid custom cutting—from small test chips to 450 mm plates—on high-temperature glass (Borofloat®,
Eagle XG, D263 T) or economical soda-lime.
Description
The BBP-650 delivers exceptional performance across the red spectrum with a center wavelength of 644 nm and a generous 82 nm FWHM passband (611-693 nm). Peak transmission reaches 94.7 %, making this filter ideal for applications requiring broad red light capture. The filter blocks visible light outside the red region with strong efficiency, though it exhibits minor UV leakage at 8.1 % - a characteristic acceptable for most red imaging work where UV rejection is secondary.
Key Advantages
- Broad passband – 82 nm FWHM spanning 611-693 nm captures the full red spectrum from deep crimson to near-infrared edge
- Excellent peak transmission – 94.7 % transmission at center wavelength maximizes signal collection and reduces optical losses
- Hard-oxide dichroic coating – Ion-assisted deposition ensures durability across thermal cycling and environmental stress
- Custom format flexibility – Available in round, square, and free-form blanks from 5 mm to 450 mm with thicknesses of 0.21-3.8 mm
- Multiple substrate options – Choose from Borofloat, soda-lime, Schott D263 T, or Corning Eagle XG for your optical system
Typical Applications
- Machine vision systems – Color detection and red-component imaging in industrial inspection and quality control
- Scientific sensing – Spectroscopic analysis of red-emitting fluorophores and biological samples
- Medical imaging – Red LED excitation in diagnostic and therapeutic optical instruments
- Industrial processing – Wavelength-specific monitoring in laser machining and materials processing
- Emerging AR/VR – Red-channel component in advanced display and spatial computing systems
Prototype the BBP-650 in your system with custom formats available in weeks. We support production volumes from single units to high-throughput manufacturing.
FAQ
BBP-650 FAQ
What is BBP-650 and what is it used for?
BBP-650 is a Broad-spectrum red imaging bandpass. The BBP-650 delivers exceptional performance across the red spectrum with a center wavelength of 644 nm and a generous 82 nm FWHM passband (611-693 nm). Peak transmission reaches 94.7 %, making this filter ideal for applications requiring broad red light capture. Common uses include Machine vision systems, Scientific sensing, Medical imaging, and Industrial processing.
What are the key optical specs of BBP-650?
Key published specs for BBP-650 include Centre wavelength (CWL): 652.4 nm; Bandwidth (FWHM): 82.8 nm; Peak transmittance: ≥ 94.7 % T; Passband range: 611 – 694 nm; Edge steepness: ~19 nm (10 → 90 % per edge).
What applications is BBP-650 best suited for?
BBP-650 is commonly used for Machine vision systems, Scientific sensing, Medical imaging, and Industrial processing. Machine vision systems - Color detection and red-component imaging in industrial inspection and quality control.
Can BBP-650 be customized for size, substrate, or coating requirements?
KUPO lists the construction for BBP-650 as Ion-assisted hard-oxide; 5 – 450 mm shapes, 0.21 – 3.8 mm thick. Published custom options include CWL shifting, bandwidth tuning, custom blocking ranges, rapid prototypes. Custom format flexibility - Available in round, square, and free-form blanks from 5 mm to 450 mm with thicknesses of 0.21-3.8 mm.
What should I know about angle of incidence and durability for BBP-650?
The published angle of incidence for BBP-650 is 0° (normal incidence); custom angles available. The hard-oxide coating is built for repeated handling, heat, and cleaning.
