Short-pass filter delivering vivid blue (410 – 490 nm), a soft mid-VIS dip, and a useful NIR tail—perfect when you need cool colour plus an IR channel.
BH-S18 offers a bright royal-blue window (410 – 490 nm) followed by a gentle dip that bottoms near 5 % around 610 nm—enough to knock down green-orange glare without the black-hole look of a full notch filter. Beyond 700 nm transmission rises again, reaching ~20 % at 700 nm and ~40 % by 780 nm, giving designers a built-in IR “leak” for depth cameras, eye-tracking, or alignment beacons. The ion-assisted hard-oxide stack shrugs off heat, humidity, solvents, and repeated cleaning. KUPO can trim edges, flatten the tail, supply 45° AOI versions, or coat Borofloat, soda-lime, Schott D263 T, or Corning Eagle XG substrates in any outline from 5 mm chips to 450 mm plates, 0.21 – 3.8 mm thick, with prototypes in about two weeks.
BH-S18 delivers a bright royal-blue window, a gentle mid-visible dip, and a controllable near-IR rise. Transmission is already above 90 % by 410 nm and stays flat (≈ 92–94 %) to about 490 nm. Beyond 510 nm it falls quickly, reaching a minimum of ~5 % around 610 nm. The curve then turns upward, hitting ~20 % at 700 nm and ~40 % by 780 nm—handy when you need a built-in NIR “leak” for alignment or depth sensing.
Key advantages
High blue output – > 90 % T from 410 nm to 490 nm for LEDs, lasers, or cool-tone stage washes.
Soft mid-band notch – < 10 % T between ~560 nm and 630 nm suppresses green–orange glare without the harsh “black hole” of a full notch filter.
Useful NIR tail – Rising transmission above 700 nm provides a built-in channel for eye-tracking, depth cameras, or IR beacons.
Hard-oxide durability – Ion-assisted coating survives heat, humidity, solvents, and repeated cleaning.
Size & shape freedom – Any outline from 5 mm chips to 450 mm plates, thicknesses 0.21 mm – 3.8 mm.
Typical applications
Stage & architectural lighting – Create chilly ice-blue atmospheres while taming warm spill; the gentle NIR tail supports tracking systems.
Dual-mode vision – Use blue lighting for inspection and the NIR rise for depth or eye-safe ranging without extra optics.
Interactive displays & AR/VR – Inject vivid blue graphics yet leave just enough 750 nm energy for camera-based gesture or gaze sensing.
Fluorescence screening – Excite CFP/FITC with blue, dampen green/orange autofluorescence, and keep an IR reference path.
Photographic effects – Sculpt LEDs into cool-tone key lights while preserving a subtle infrared accent for creative sensors.
Substrate options
KUPO Optics coats Borofloat®, soda-lime, Schott D263 T borosilicate, or Corning Eagle XG glass—cut to custom shapes (round, square, hex, freeform) from 5 mm to 450 mm and thicknesses 0.21 mm to 3.8 mm. Prototypes ship in as little as two weeks.