CRI-1 Color Rendering Improvement Filter

CRI-1 is a colour-rendering improvement (CRI) filter that gently warms and smooths spiky LED/HMI spectra by trimming deep blue and broad yellow-green while preserving strong long-red. Transmission is low in the blue (~22–26% from ~380–440 nm), rises steeply to ~90–92% around ~480–505 nm, then forms a mid-band trough of ~50–55% across ~520–590 nm. From ~630 nm it climbs to ~90–93% through ~740 nm and finishes near ~94–95% by ~780 nm.

Key advantages

• Lift CRI/TLCI and R9 — tames deep blue and the ~520–590 nm region while keeping the long-red energy that drives natural skin and rich materials.

• Blue trim, not a crush — keeps detail by allowing a clean pass near ~480–505 nm while reducing harshness below ~440 nm.

• Mid-band smoothing — broad, low-ripple shaping (~50–55% T) across ~520–590 nm avoids magenta/green swings and banding.

• High red throughput — ~90–93% T from ~630–740 nm, easing to ~94–95% by ~780 nm, for vivid reds and flattering faces.

• Production-ready durability — hard dielectric stack stands up to fixtures, stages, and location work; optional rear-surface AR and slight wedge suppress ghosts.

• Custom formats — Borofloat®, Eagle XG, or D263 T (0.21–3.8 mm) for high-temp use to ~450 °C; soda-lime for ≤150 °C. Sizes 5–450 mm.

Typical applications

• Cinema/TV lighting — raise TLCI/CRI and skin-tone accuracy with less in-camera correction.

• Photography & events — warmer, more flattering faces and textiles under LED or HMI.

• Retail, museum & hospitality — reduce green cast and reveal natural reds in merchandise and art.

• Architectural & display — refine off-the-shelf luminaires for premium colour.

• Machine vision — stabilize channels when red features matter and blue/green glare is problematic.

Need test chips tomorrow or thousands next quarter? CRI-1 filters are coated and cut-to-size (including dicing) to your exact spec—fast.