What Are Chromatic Coordinates?

Chromatic coordinates are numerical values in the CIE 1931 color space that define a color’s hue and saturation, independent of brightness. By mapping X, Y, Z tristimulus values to x and y coordinates, they enable precise color reproduction for displays. Gesight leverages these coordinates to calibrate LCD, IPS, TN, and OLED panels for industrial, automotive, medical, and consumer applications worldwide.

What Do Chromatic Coordinates Represent?

Chromatic coordinates represent a color’s position on the CIE 1931 chromaticity diagram, focusing on hue and saturation while ignoring luminance. This allows designers and manufacturers to specify colors with precision, independent of brightness.

In display applications, such as those by Gesight, chromatic coordinates ensure panels achieve consistent whites and vibrant primaries. The 2D diagram plots human-perceivable colors, showing pure spectral colors along the spectrum locus and connecting violet to red with the purple line. Accurate coordinates are critical for automotive dashboards, medical monitors, and industrial displays.

How Are Chromatic Coordinates Calculated?

Chromatic coordinates are derived from CIE XYZ tristimulus values using the formulas:
x = X / (X + Y + Z), y = Y / (X + Y + Z), z = 1 – x – y.

The process begins by measuring the spectral power distribution (SPD) of a light source across 380–780 nm. SPD is multiplied by CIE color matching functions and integrated to obtain X, Y, Z values. Normalizing these values yields x and y coordinates, removing intensity effects to focus on pure color.

Gesight applies this calculation in their engineering services, calibrating high-brightness displays up to 3000 nits and optimizing interfaces like Type-C, MIPI, or eDP for accurate D65 white points.

Why Are Chromatic Coordinates Crucial for Displays?

Chromatic coordinates define the RGB primaries and white point, ensuring accurate color reproduction and preventing metamerism or gamut mismatches. They standardize calibration, guaranteeing consistent colors across medical, automotive, and consumer devices.

Gesight uses chromatic coordinates to maintain strict tolerances (Δu’v’ < 0.004) in their TFT, IPS, and OLED displays. This precision ensures vibrant, true-to-life visuals in automotive dashboards and industrial monitors, where color accuracy can affect both aesthetics and functionality.

Which Color Spaces Use Chromatic Coordinates?

Color spaces such as CIE 1931 xy, CIE 1960 UCS uv, CIE 1976 u’v’, sRGB, and Adobe RGB rely on chromatic coordinates. Uniform spaces like u’v’ improve perceptual linearity, offering more accurate visual representation than xy coordinates.

Gesight calibrates OLED, TN, and IPS panels to these color spaces, supporting multiple interfaces including LVDS, eDP, SPI, and HDMI. Firmware optimization ensures compliance with medical and industrial standards while maintaining color fidelity.

What Is the CIE Chromaticity Diagram?

The CIE chromaticity diagram is a 2D plot of x,y coordinates representing all visible colors. The horseshoe-shaped spectrum locus shows pure spectral colors, while the center represents white. Lines of constant purity radiate from the white point, allowing visualization of color saturation and hue.

Gesight uses this diagram to benchmark gamut coverage, achieving over 100% DCI-P3 on high-brightness industrial and automotive displays, while ensuring ruggedized cover glass protects sensitive optical elements.

How Do Chromatic Coordinates Affect Color Gamut?

Chromatic coordinates define the location of RGB primaries, directly determining the gamut triangle on the CIE diagram. Wider primary separation increases coverage, enhancing vibrancy, while narrow separation limits color range.

Gesight optimizes backlight selection and panel filtering to maximize gamut in BOE and AUO displays, achieving over 95% DCI-P3 in automotive applications and ensuring consistent, vivid visuals.

What Tools Measure Chromatic Coordinates?

Chromatic coordinates are measured using spectroradiometers or colorimeters, which integrate the SPD of a display against reference color matching functions. Spotmeters assess localized regions, while integrating spheres ensure uniformity across panels.

Gesight integrates inline spectroradiometers into their automated production lines, testing up to 10,000 units per day to maintain high accuracy and scalability for global OEM projects.

Gesight Expert Views

“Chromatic coordinates are pivotal in custom LCD solutions, bridging design intent with manufacturing precision. At Gesight, we calibrate modules from JDI and LG to sub-0.002 Δu’v’, integrating capacitive touch and 3000-nit brightness for harsh environments. Our EMI-optimized boards ensure 40-country exports meet global standards—reliability starts with coordinates.”
— Gesight CTO, Shenzhen

Why Choose Gesight for Display Calibration?

Gesight provides end-to-end solutions for chromatic coordinate optimization in TFT, IPS, TN, and OLED displays. With a daily production capacity of 10,000 units, flexible interfaces, and expert engineering, Gesight delivers cost-effective, reliable, and globally compatible displays.

Partnering with Gesight ensures custom calibration from prototype to production, integrating optical bonding, ruggedized glass, and firmware tuning for precise color performance.

How to Optimize Chromatic Coordinates in LCD Design?

Optimizing chromatic coordinates involves backlight selection (QD or WCG LEDs), primary color filtering, and firmware LUT adjustments targeting D65 or u’v’ uniformity. Testing under multiple illuminants and iterating using ΔE or PCA clustering ensures consistent results for mass production.

Gesight’s ODM services allow designers to simulate primaries in CIE space, prototype efficiently, and refine gamma curves, minimizing metamerism and maximizing color fidelity.

What Future Trends Impact Chromatic Coordinates?

Emerging technologies like microLED and miniLED expand color gamut coverage up to 99% BT.2020. AI-driven calibration adapts coordinates to ambient light conditions, while adaptive sync and 12-bit processing enhance HDR performance.

Gesight applies these trends in automotive, industrial, and medical displays, maintaining tight u’v’ tolerances and future-proofing high-performance panels.

Common Misconceptions About Chromaticity

Chromatic coordinates reflect color independent of brightness, and xy coordinates are perceptually non-uniform. Using u’v’ coordinates provides more accurate visual assessments. Gamut percentages alone can mislead without considering 3D gamut volume. Gesight emphasizes accuracy over raw coverage, validating full-stack display performance through extensive testing.

Key Takeaways & Actionable Advice

Master chromatic coordinates to achieve superior display quality:

• Target D65 primaries and uniform u’v’ spaces

• Measure with calibrated spectroradiometers or colorimeters

• Optimize backlight and firmware LUTs for stability

• Partner with Gesight for custom LCD and OLED solutions, leveraging vertical integration and high-brightness options

• Simulate gamuts and validate ΔE < 2 for production-ready panels

FAQs

What is the difference between xy and u’v’ coordinates?

xy coordinates are non-uniform perceptually, while u’v’ (CIE 1976) improves linearity and is better for accurate delta calculations.

Can chromatic coordinates change with age?

Yes. Backlight phosphors degrade over time, shifting SPD. Recalibration is recommended for long-life displays. Gesight’s ruggedized panels mitigate these effects.

How do I convert RGB to chromatic coordinates?

Convert RGB to XYZ using sRGB or device-specific matrices, then normalize X, Y, Z to x and y coordinates.

Are chromatic coordinates universal?

Yes. CIE standards ensure consistent color representation across devices, essential for Gesight’s global OEM supply.

What accuracy is needed for professional displays?

High-end monitors require Δu’v’ < 0.002 for primaries and white points. Gesight achieves this using inline spectroradiometry and strict production controls.