|
|
Line 1: |
Line 1: |
− | {{stub}}
| + | =Definition= |
− | | + | =Examples= |
− | = Color Rendering Index =
| + | [[Image:trend-graph-calm-technology.png|left|300px]] |
− | | + | |
− | == Definition ==
| + | |
− | The Color Rendering Index (CRI) is a quantitative measure of a light source's ability to reveal the colors of objects faithfully in comparison with an ideal or natural light source. It is expressed on a scale from 0 to 100, where 100 represents the most accurate color rendering. CRI is critical in lighting design, photography, art, and various industries where color accuracy is essential.
| + | |
− | | + | |
− | Key characteristics of CRI include:
| + | |
− | * Measures how well a light source displays the colors of an object compared to a reference light source
| + | |
− | * Calculated by comparing the color of objects under the test light source to their color under an ideal light source
| + | |
− | * Ranges from 0 to 100, with higher numbers indicating better color rendering
| + | |
− | | + | |
− | == Technical Overview ==
| + | |
− | The CRI is determined by measuring the color shift of eight standard color samples when illuminated by the test light source compared to a reference source (typically sunlight or an incandescent lamp). These color samples represent different hues and saturations:
| + | |
− | * Ra: The general color rendering index calculated from the first eight color samples
| + | |
− | * Extended CRI (Ra16): Includes additional color samples for more comprehensive analysis
| + | |
− | | + | |
− | == Examples ==
| + | |
− | Different light sources have varying CRI values:
| + | |
− | * Incandescent bulbs: Nearly 100 CRI (excellent color rendering)
| + | |
− | * Fluorescent lights: Typically 50-80 CRI (moderate color rendering)
| + | |
− | * LED lights: Can range from 70 to 95+ CRI (depending on the specific type)
| + | |
− | * Sodium vapor lamps: Very low CRI (around 20-30)
| + | |
− | | + | |
− | [[Image:low-cri-light-calm-technology.png|left|300px]] | + | |
− | | + | |
− | [[Image:high-cri-light-calm-technology.png|left|300px]]
| + | |
− | | + | |
− | | + | |
| {{clear}} | | {{clear}} |
− | <br> | + | <br> |
− | | + | =References= |
− | == Practical Applications ==
| + | |
− | CRI is crucial in various fields:
| + | |
− | * Art galleries and museums
| + | |
− | * Photography and film lighting
| + | |
− | * Architectural and interior design
| + | |
− | * Medical and scientific laboratories
| + | |
− | * Retail display lighting
| + | |
− | | + | |
− | == Limitations ==
| + | |
− | While CRI is widely used, it has some limitations:
| + | |
− | * Does not account for the full spectrum of color perception
| + | |
− | * Does not measure color temperature or spectral distribution
| + | |
− | * May not perfectly represent how humans perceive color in all conditions
| + | |
− | | + | |
− | == References ==
| + | |
− | # International Commission on Illumination (CIE) publications
| + | |
− | # Lighting research publications
| + | |
− | # Manufacturer specifications for light sources
| + | |
− | # https://www.ies.org/definitions/color-rendering-index-cri-of-a-light-source/
| + | |
| | | |
− | [[Category:Light]]
| |
| __NOTOC__ | | __NOTOC__ |