CRI-7 Color Rendering Improvement Filter
CRI-7 is a colour-rendering (CRI/TLCI) filter that warms and smooths spiky LED/HMI spectra—trimming deep blue and yellow-green while preserving strong long-red for higher CRI/TLCI, better R9, and natural skin tones.
- Function: CRI/TLCI improvement; reduces deep blue & yellow-green, preserves long-red
- Near-blue & notch: ~86–90 % (395–425 nm) with deep blue notch ~8–12 % at 445–455 nm
- Cyan window: Clean pass ~86–89 % T across 495–505 nm (keeps whites/skies crisp)
- Green trough: Broad 520–560 nm shaping; minimum ~18–22 % T near 535–550 nm
- Long-red throughput: ~92–95 % T from 640–740 nm; gentle roll-off to ~78–82 % by ~780 nm
- Construction & format: Durable dielectric on Borofloat®, Eagle XG, D263 T, or soda-lime • 5–450 mm • 0.21–3.8 mm • options: rear-AR & slight wedge
Learn more
CRI-7 pairs a deep blue notch with a moderated green trough to lift CRI/TLCI and R9 without magenta/green casts or banding. Its preserved cyan window keeps whites clean, while strong long-red supports vivid reds and flattering faces.
Typical applications • Cinema/TV lighting • Photography & events • Retail/museum/hospitality • Architectural & display • Machine vision (when red features matter).
Need test chips tomorrow or thousands next quarter? CRI-7 filters are coated and cut-to-size (including dicing) to your exact spec—fast.
Description
CRI-7 is a colour-rendering improvement (CRI) filter that warms and smooths spiky LED/HMI spectra by trimming deep blue and broad yellow-green while preserving strong long-red. Transmission runs high in near-blue (~86–90% from ~395–425 nm), drops to a deep notch of ~8–12% around ~445–455 nm, rebounds to ~86–89% across ~495–505 nm, then forms a broad trough through ~520–560 nm with a minimum near ~535–550 nm of ~18–22%. From ~630 nm it climbs rapidly to ~92–95% through ~640–740 nm, easing to ~78–82% by ~780 nm.
Key advantages
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Raise CRI/TLCI and R9 — moderates the ~450 nm spike and the ~520–560 nm band while keeping long-red energy for natural skin, wood, food, and fabrics.
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Dual-notch, cyan window profile — deep blue notch near ~445–455 nm and mid-green trough ~535–550 nm, with a clean ~495–505 nm pass that keeps whites and skies crisp.
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High long-red throughput — about 92–95% T from ~640–740 nm, with a gentle roll-off toward ~780 nm for vivid reds and flattering faces.
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Predictable shaping — smooth, low-ripple transitions avoid banding and keep colour moves consistent across fixtures.
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Built for production — rugged dielectric stack; optional rear-surface AR and slight wedge to suppress ghosts in lenses and flat ports.
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Custom formats — Borofloat®, Eagle XG, or D263 T (0.21–3.8 mm) for high-temp duty to ~450 °C; economical soda-lime for ≤150 °C. Sizes 5–450 mm.
Typical applications
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Cinema/TV lighting — raise TLCI/CRI and skin-tone accuracy with less in-camera correction.
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Photography & events — warmer, more flattering faces and textiles under LED or HMI.
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Retail, museum & hospitality — reduce green cast and reveal natural reds in merchandise and art.
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Architectural & display — refine off-the-shelf luminaires for premium colour.
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Machine vision — stabilize channels where red features matter and blue/green glare is problematic.
Need test chips tomorrow or thousands next quarter? CRI-7 filters are coated and cut-to-size (including dicing) to your exact spec—fast.
