BBP-470A Bandpass Filter (455-495 nm Passband)
BBP-470A isolates the blue channel with ~90 % throughput across ~455–500 nm and near-baseline leakage across the rest of VIS–NIR—built for excitation and high-contrast imaging.
- Main passband (T): ~88–91 % T @ 455 – 500 nm
- Cut-on / cut-off: Steep edges around ~450 nm and ~505 nm
- Out-of-band (VIS–NIR): ~0–2 % T across ~300 – 1100 nm
- SWIR window: ~85–88 % T @ 1180 – 1210 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-470A is a visible bandpass centred near 470 nm, delivering a high-transmission
blue window (~88–91 %) across ~455–500 nm with steep edges for clean colour separation. Outside the
main passband, transmission stays near baseline (~0–2 %) across most of the 300–1100 nm range,
keeping mixed illumination from washing out contrast or overloading sensors.
One important note: the spectrum shows a strong secondary window in the far red / short-wave infrared
near ~1180–1210 nm (peaking ~85–88 %). If your detector has response there, KUPO can add an
additional blocking stack to fully suppress that band.
Typical uses: blue excitation for fluorescence, 470 nm LED inspection lighting, microscopy
colour-channel isolation, projection/instrument channel selection, and photometry where stable blue
throughput matters. KUPO supplies rear-surface AR, slight wedge, and rapid custom cutting—from small
test chips to 450 mm plates—on high-temp glass (Borofloat®, Eagle XG, D263 T) or economical soda-lime.
Description
The BBP-470A is a moderate-width blue filter centered at 477 nm with a 40 nm FWHM passband (455-495 nm). Peak transmission reaches 90.5 %. This 'A' variant offers a middle ground between full-spectrum blue capture and narrow isolation, making it ideal for color imaging applications where blue definition matters but some green spillover is acceptable. The 12.2 % SWIR leakage provides an optional thermal sensing channel.
Key Advantages
- Moderate blue passband width – 40 nm FWHM balances light collection with color definition for machine vision color detection
- Controlled green overlap – 30.2 % blue transmission with managed 17.3 % green spillover for true blue signal preservation
- Hard-oxide ion-assisted coating – Dichroic multilayer design withstands thermal cycling and environmental exposure without drift
- Flexible format selection – Custom round, square, and free-form blanks from 5 mm to 450 mm; thickness 0.21-3.8 mm
- Substrate diversity – Borofloat, soda-lime, Schott D263 T, and Corning Eagle XG match your optical design needs
Typical Applications
- Color machine vision – Industrial inspection systems using RGB color detection with blue-channel emphasis
- Blue LED systems – Optimal passband for 465-480 nm LED illumination in automation and quality control
- Scientific sensing – Moderate-width blue photometry in optical research and analytical measurements
- Biomedical imaging – Blue fluorescence channel in diagnostic and research optical instruments
- Display technology – Blue-channel filtering in projection systems and advanced imaging displays
Deploy BBP-470A in your blue-channel system with rapid prototyping and custom manufacturing. Scales seamlessly from single units to production volumes.
FAQ
BBP-470A FAQ
What is BBP-470A and what is it used for?
BBP-470A is a Moderate-width blue bandpass - A variant. The BBP-470A is a moderate-width blue filter centered at 477 nm with a 40 nm FWHM passband (455-495 nm). Peak transmission reaches 90.5 %. Common uses include Color machine vision, Blue LED systems, Scientific sensing, and Biomedical imaging.
What are the key optical specs of BBP-470A?
Key published specs for BBP-470A include Centre wavelength (CWL): 475.1 nm; Bandwidth (FWHM): 41.4 nm; Peak transmittance: ≥ 90.5 % T; Passband range: 454 – 496 nm; Edge steepness: ~10 nm (10 → 90 % per edge).
What applications is BBP-470A best suited for?
BBP-470A is commonly used for Color machine vision, Blue LED systems, Scientific sensing, and Biomedical imaging. Color machine vision - Industrial inspection systems using RGB color detection with blue-channel emphasis.
Can BBP-470A be customized for size, substrate, or coating requirements?
KUPO lists the construction for BBP-470A 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. Flexible format selection - Custom round, square, and free-form blanks from 5 mm to 450 mm; thickness 0.21-3.8 mm.
What should I know about angle of incidence and durability for BBP-470A?
The published angle of incidence for BBP-470A is 0° (normal incidence); custom angles available. The hard-oxide coating is built for repeated handling, heat, and cleaning.
