Mirror-bright across the visible yet vents IR heat—BH-A20 dual-finish gobo glass keeps projections vivid and cool.
BH-A20 pairs a cold-mirror dielectric with a matte-black reverse to create a
“black-and-white” gobo plate that reflects the full visible spectrum while bleeding off
near-infrared heat. At a 45 ° angle the coating rises from < 10 % R below ~325 nm to
> 90 % by 390 nm, rides a 92 – 94 % plateau through ~560 nm, then glides toward ~80 %
at 800 nm—so projected images stay punchy and colour-true, yet IR load is vented away from
the gate.
The 0.5–1 mm aluminium core cuts cleanly on laser or water-jet tables, enabling intricate
logos, abstract break-ups, or heat-shield inserts that drop straight into ellipsoidals,
scanners, follow-spots, or architectural projectors. Dense ion-beam-sputtered oxides meet
MIL-M-13508C abrasion, adhesion and humidity specs, surviving daily wipe-downs and high-duty
cycles.
Typical uses: swap glass gobos for a brighter, cooler fold mirror in profile spots;
protect colour filters and iris assemblies as a cold-mirror heat shield; steer red lasers in
RGB scanners while the black back masks spill; or flip the plate to use the matte side for
aperture stops and beam dumps.
Need odd shapes, tighter IR rejection, or an anti-reflection coating on the back? KUPO’s
in-house IBS lines can tweak BH-A20 and ship prototypes in a matter of days.
BH-A20 is KUPO Optics’ dual-finish “black-and-white” gobo material. One face carries a high-efficiency cold-mirror dielectric that sends nearly the entire visible spectrum forward while bleeding off near-IR heat; the reverse face remains matte-black for masking or intricate pattern cut-outs. Use it in ellipsoidal spots, projectors, scanners, or architectural fixtures whenever you need maximum image punch without cooking the gate.
At 45 ° AOI the curve climbs from under 10 % reflectance below roughly 325 nm to beyond 90 % by about 390 nm, rides a 92 – 94 % plateau through ~560 nm, then eases down to ~80 % by 800 nm. Visible light stays bright and colour-neutral, while the IR roll-off lets heat escape and protects downstream components.
Key advantages
Broadband visible reflection — >92 % R across 400 – 560 nm keeps projected images vivid and white-balanced.
Heat management — Gradual IR fall-off vents thermal energy, extending lamp, gel, and substrate life.
UV suppression — <20 % R 310-410 nm shields photosensitive media from harmful ultraviolet splash.
Lightweight, laser-cuttable aluminium — 0.5 – 1 mm cores cut cleanly yet resist warping under stage heat.
Stage-tough durability — Hard-oxide dielectric plus anodised metal shrug off humidity, solvents, and daily wipe-downs.
Typical applications
Ellipsoidal & profile spots — Swap glass gobos for a brighter, cooler mirror while the black back masks spill.
Architectural mapping — Steer vivid imagery onto façades without IR bake-back inside compact housings.
Follow-spot heat shields — Protect colour filters and iris assemblies with a cold-mirror insert.
Entertainment laser scanners — Use the bright face for beam steering, the dark face for aperture stops.
Optical test benches — Create low-cost folding mirrors that double as beam dumps when flipped.
Need odd shapes, a steeper IR drop, or AR-coated backs? KUPO Optics can prototype and ship BH-A20 variants fast to keep your production or research timeline on track.