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The move to LED (light-emitting diode) lighting is inevitable, driven by market dynamics, sustainability initiatives, and regulatory frameworks. Lighting constitutes 17% of electricity consumption in U.S. commercial buildings, and the energy-efficient nature of LED lighting is both environmentally and economically beneficial. LEDs use 90% less energy than traditional incandescent lighting. They are also significantly more efficient than compact fluorescent lamps (CFLs), last 10 times longer, and generate less heat. Regulatory changes, like the EU Directive restricting mercury in fluorescent lamps by 2025 and the U.S. Department of Energy (DOE) finalized efficiency standards, are speeding up this shift to LED.

As the world moves toward LED adoption, brands, manufacturers, and suppliers need to carefully evaluate how this shift will impact their products, particularly regarding color. LED lighting has unique spectral properties that can influence color perception and quality control, making it essential for brands and manufacturers to update their color development processes accordingly.

Understanding Color Perception

Color perception is inherently linked to lighting. A product’s color may look different depending on the light source it’s viewed under—whether in a store, under home lighting, natural light, or on an assembly line. Product teams and quality control professionals must assess the effect of lighting changes on a product to ensure it meets visual standards and customer expectations. This means selecting every light source under which the final product will be seen and evaluating color. For instance, if you’re producing textiles, you’ll want to make sure the color of all sewn pieces matches under daylight and the LED lighting used in retail stores and homes. Without proper attention to lighting conditions, a product might pass quality control inspections under one light source but appear different—and perhaps unsatisfactory—under another. This is especially important for final assembly, where different components must match.

 

Image 1-3: Reflectance curves for D65 (average daylight) LED, Cool White Fluorescent (CWF) LED and A LED (mimics incandescent lighting).

 

Light sources like daylight, incandescent, fluorescent, and now LEDs, all have different reflectance curves, which impact how colors are perceived. For example, incandescent lighting emits more energy in the red spectrum, causing objects to appear redder compared to daylight or other illuminants with high color correlated temperature (CCT).

As industries transition to LED technology, Spectral Power Distribution (SPD) becomes another consideration in visual evaluation and quality control programs. An SPD curve illustrates the intensity of light at each wavelength across the visible spectrum, typically ranging from 380 nm to 780 nm, providing detailed insights into a light source’s color characteristics and quality. Unlike CFL or fluorescent lights, which have narrower peaks, LED spectrums are smoother and wider. This difference will impact color perception.

For example, CFLs are effective for testing metameric samples at specific wavelengths, but LEDs will introduce new metameric challenges. Fortunately, advanced phosphor LED technologies can replicate the spectral characteristics of fluorescent lights, ensuring more consistent color assessments during the transition. Companies require time to adapt to LED, as many have specified certain CFL illuminants in their standard operating procedures. Quality control professionals need to factor in SPD curves and select LEDs that accurately replicate the standard for a smoother transition.

LED’s Impact on Color Quality Control

When transitioning to LED lighting, manufacturers must consider how this change impacts existing color standards and evaluation procedures. Two key concepts that must be addressed include flare and metamerism. Both relate to how colors behave under different lighting conditions and impact quality control, but in different contexts.

 

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Flare refers to a change in a color’s appearance when viewed under different lighting conditions. While some color shift is natural and expected, manufacturers need to determine whether the degree of flare is objectionable or not. As companies switch to LED lighting, designers and suppliers need to assess how this change affects product colors and whether any adjustments are necessary to minimize negative effects on visual consistency.

Metamerism occurs when two color samples match under one light source but differ under another. This inconsistency can create problems in industries like apparel, footwear, and automotive, where products made from different materials and colorants must match under all types of illumination. Metameric matches are most common in neutral colors like grays, whites, and dark shades. This effect is problematic for visual consistency across materials, but it can be minimized by evaluating samples in a light booth under multiple lighting conditions, including different LED sources. Keep in mind that samples with directional characteristics, such as woven fabric and textured plastic, must be viewed from the same angle to avoid geometric metamerism.

Image 5: Reflectance curves of a metameric pair

Updating Color Workflows

As LEDs become more prevalent, brands and manufacturers need to update their color development and quality control processes to reflect this lighting shift. To effectively transition to LED lighting, companies can focus on several key strategies:

1. Standardize Lighting Across the Workflow - From brand to designer to supplier and manufacturer, all stakeholders involved in the production process must evaluate color under the same LED lighting conditions. This can be a standard CIE LED illuminant that matches as closely as possible the LED used in the environment in which the products will be sold or an LED standard type defined by the brand. Any LED lighting changes must be communicated with suppliers and quality control teams to ensure all parties match color under the same conditions. This coordination will prevent discrepancies across the supply chain and help maintain a consistent visual appearance.
2. Upgrade Light Booths – Light booths simulate various lighting conditions to visually evaluate how products will appear in different environments. Older light booths typically offer daylight (D50, D65), incandescent tungsten, and fluorescent light. There are many reasons to consider upgrading your light booth to include LED lighting. In addition to complying with the EU ban on fluorescent lighting, LED light booths are more energy efficient, easier to maintain, require no warm-up time, and are better at replicating daylight.



Image 6: Visual evaluation of an automotive part using a X-Rite light booth.

3. Align Color Measurement Devices: Consistency in measurement is critical. All devices, including spectrophotometers, light booths, and quality control software, must be set to the same illumination standard or the results will be inaccurate, leading to color mismatches. Working with one solution provider can ensure a connected workflow where measurement devices, software, and light booths all speak the same language for color assessment consistency.
4. Assess Your Color Standards: It’s important for manufacturers to evaluate their colors standards under LED lighting to determine the impact of flare compared to the previous light sources. It may be necessary to adjust color palettes or repeat the color matching process and reformulate to maintain consistency.
5. Evaluate Early and Frequently: The earlier manufacturers detect potential color inconsistencies under LED lighting, the more time to address the issue before it leads to costly waste or rework. Frequent visual evaluations at different stages from formulation to production can help prevent significant discrepancies, reduce waste, avoid production delays, and maintain color quality.
6. Employee Training: Educating all employees who handle and approve color is essential. Training should cover the basics of color science, the principles of color communication and evaluation, lighting, and the proper use of color measurement tools and software. Numerous online and in-person courses are available through industry associations and vendors for new team members or those seeking a refresher. In addition, employee training should include color vision tests, such as the Farnsworth Munsell 100 Hue Test, to ensure everyone can discern color differences.

The transition to LED must start now. Brands, suppliers, and manufacturers who fail to adapt risk costly mismatches and dissatisfied customers. In industries where color precision is paramount, small investments in integrating LED lighting into color workflows can help all stakeholders avoid pitfalls and turn the LED shift into a competitive advantage. Don’t wait until color problems arise—prepare for LED today.