BH-A11 Blue Transmission Mirror
BH-A11 drives pure 390 – 475 nm blue through your light engine while reflecting green-to-red energy for colour-clean RGB splits at a compact 45 ° fold.
- Blue passband 390–475 nm: > 95 % transmission @ 45 ° AOI
- Green-red block 500–700 nm: < 0.5 % T (≥ 99.5 % R)
- IR tail > 730 nm: ~15 – 25 % T eases thermal load
- High-flux rating: Hard-oxide IBS stack handles > 10 W / cm²
- Angle stability: < ±5 nm spectral shift 40–50 ° AOI
- Custom formats: 5 – 450 mm blanks in Borofloat®, Eagle XG, D263 T, soda-lime
Learn more
Engineered for modern 3-LCD and LCoS prisms, BH-A11 passes just the blue primary while
redirecting the full green-to-red band with > 99 % reflectance, preventing colour bleed that
would desaturate high-gamut projectors. An intentionally moderate IR tail above 730 nm vents
lamp or laser heat away from panels and integrator rods, extending life and cutting fan noise.
The ion-beam-sputtered oxide stack survives sustained 10 W / cm² flux and meets MIL abrasion specs,
yet keeps wave-front error below λ/10 for sharp, ghost-free images.
KUPO stocks popular sizes for immediate trials, and can tweak centre wavelength, edge steepness,
or backside AR coatings in as little as two weeks—delivering chips as small as 5 × 5 mm or
plates up to 450 mm to match your optical drawing.
Description
BH-A11 is a 45 ° dichroic “blue-pass” mirror engineered to transmit only the blue primary (≈ 390 – 475 nm) while reflecting the entire green-to-red band for colour-separating light-engine prisms and phosphor/panel projectors. The coating delivers > 95 % transmission across the blue window, then plunges to < 0.5 % through the green and red (≈ 500 – 700 nm), preventing unwanted bleed that would desaturate the image. A controlled IR tail above 730 nm eases thermal load on downstream components without compromising visible contrast.
Key advantages
-
High blue throughput (> 95 % 390 – 475 nm) – maximises luminous efficiency for laser-phosphor and UHP-lamp engines.
-
Deep green-to-red rejection (< 0.5 % 500 – 700 nm) – produces razor-clean spectral separation for RGB combining prisms.
-
Hard-oxide stack rated to 10 W/cm² – withstands the high-flux, high-temperature environment inside compact projectors.
-
Minimal spectral shift at 45 ° AOI – preserves colour balance even as optical tolerances vary.
-
Custom glass options – Borofloat®, Eagle XG, D263 T (≤ 450 °C) or soda-lime (≤ 150 °C) from 5 × 5 mm to 450 mm, 0.21 – 3.8 mm thick.
Typical applications
-
3-LCD and LCoS projection prisms – pass blue to the B-panel while reflecting R/G to their respective paths.
-
Laser-phosphor wheel systems – separate blue pump light from yellow/green phosphor emission for improved colour gamut.
-
Digital cinema lamp houses – dump red/IR heat to prolong integrator-rod life and reduce fan noise.
-
Head-up & head-mounted displays – compact RGB combiners where low angle dispersion and high efficiency are critical.
-
Spectral imaging illuminators – create pure blue excitation channels without green/red contamination.
Need samples next week or scheduled production next quarter? BH-A11 mirrors are coated, cut and shipped to your exact drawing—fast.
