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CRI-18 Spectral-shaping filter for color correction

CRI-18 is a spectral-shaping filter for color correction. It reshapes the source spectrum by attenuating selected visible wavelengths rather than adding missing colors.

  • Measured wavelength range: 380-800 nm
  • 400-500 nm: 44.4% average transmission
  • 500-600 nm: 46.3% average transmission
  • 600-700 nm: 92.3% average transmission
  • Custom options: Wavelength response, dimensions and operating conditions

Values shown are sample measurements. Final specifications are agreed for your order.

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Spectral-shaping filter for color correction (CRI-18)

CRI-18 is a spectral-shaping filter for color correction. It reshapes the source spectrum by attenuating selected visible wavelengths rather than adding missing colors. Average transmission in the sample is 44.4% over 400-500 nm, 46.3% over 500-600 nm, 92.3% over 600-700 nm. The resulting light output also depends on the lamp spectrum.

Optical performance

  • Measured wavelength range: 380-800 nm. Performance outside this measured interval is not established by this curve.
  • 400-500 nm: Approximately 44.4% average transmission; the range is 12.5-92.2% in the measured curve.
  • 500-600 nm: Approximately 46.3% average transmission; the range is 24.3-92.2% in the measured curve.
  • 600-700 nm: Approximately 92.3% average transmission; the range is 74.4-95.2% in the measured curve.
  • Measured edge at 50% transmission: Approximately 470.4 nm. Interpolated absolute-transmission crossing, checked against the factory summary.
  • Customization: We can customize stock and sample-book designs. Tell us the wavelength response, size and operating conditions you need.

These values come from the measured samples and help you choose a starting design. We will agree the final specification for your order. Custom versions have their own specifications and measured curves.

Applications to consider

  • LED and discharge-lamp development: Check whether reducing selected peaks improves the balance of your light source. Compare color rendering and luminous output before and after filtering.
  • Studio and display lighting: Consider the filter when a measured color imbalance affects the desired appearance of skin tones or objects. Test with the actual source and viewing or camera conditions.
  • Color-correction trials: Compare this profile with other correction filters using the same source. A color-rendering score belongs to the resulting light, so it must be measured or calculated for that combination.

Choosing this filter

  • Evaluate the filter together with the intended light source. Color temperature, tint, color rendering and luminous output depend on that combination.
  • Tell us the size, shape and working angle you need, along with the temperature conditions inside the fixture.

Custom options

Start with this stock or sample-book design, then tell us what you need to change. We can discuss the wavelength bands, transmission, blocking, angle, glass material, size and operating conditions with you, and agree a specification for your custom filter.

Transmission spectrum

Questions about CRI-18

How do I judge whether CRI-18 suits my light source?

The filter sample averages are 44.4% over 400-500 nm; 46.3% over 500-600 nm; 92.3% over 600-700 nm. They describe transmission, not a color-rendering score. Assess the filtered lamp spectrum or measure the complete lighting setup to find out whether the change helps your application.

What does the 50% crossing near 470.4 nm mean for CRI-18?

It identifies where this measured curve crosses 50% transmission. It is useful for comparing the spectral transition, but it does not give a fixed color-temperature shift or the total light output from your lamp. For CRI-18, use the band averages above together with your source spectrum.

Discuss this filter with KUPO - include the product reference, source wavelength, working angle and required dimensions.