Light color refers to the visual impression of the color of the light emitted by a light source. It influences the ambiance, functionality, and appearance of a space, and is a crucial aspect of both indoor and outdoor lighting. Light color is measured in Kelvin (K) and can range from warm white to cool white or even bluish light .

How is light color measured?

Light color is measured in Kelvin (K) , a unit that indicates the temperature of light. The Kelvin scale refers to the color temperature of light sources, which indicates how "warm" or "cool" the light appears. This is based on the color of the light emitted by a "black frame" (a theoretical object) when heated to a certain temperature.

Light color and Kelvin scale

The Kelvin scale is used to describe what light looks like, and the different values represent different types of light color :

• <2700 K : Warm white light, similar to traditional incandescent bulbs. It's a soft, yellowish light that creates a cozy and comfortable atmosphere. This type of lighting is often used in living rooms, bedrooms, and restaurants.
• 2,700 K - 3,000 K : Soft white light, still warm, but slightly less yellow than 2,700 K. This is often used for general lighting in living areas and for atmospheric lighting.
• 3,000 K - 4,100 K : Neutral white light, less yellow and more white than warm light. It provides a bright, balanced light without feeling too cool or too warm. This is often used in kitchens, workspaces, and commercial settings.
• 4100K - 5000K : Cool white light, which is a whiter, bluer light. It is bright and vibrant, ideal for workspaces, offices, and lighting needs that require clarity and sharpness. This light helps promote concentration.
• >5,000 K : Daylight or bluish light , which most closely resembles natural daytime light. It is cool and bright, and is often used in work environments, factories, or areas that benefit from high visibility. It can also be found in outdoor lighting.

Effects of light color

1. Ambience and aesthetics :
• Warm light (below 3,000 K) creates a cozy, inviting atmosphere and is often used in living rooms, dining rooms and bedrooms.
• Cool light (above 4,000K) creates a sharper, more energetic atmosphere and is often used in workspaces, kitchens or commercial settings.
2. Work and productivity :
• Cool white light (between 4,000 and 5,000 K) can boost concentration and productivity, making it ideal for offices , workspaces , or kitchens . It increases alertness and makes it easier to see details.
• Warm light is easier on the eyes and promotes relaxation, making it ideal for spaces where you want to relax, such as a living room or bedroom.
3. Health and well-being :
• The type of light you use can also affect your sleep pattern . Blue light (higher than 5,000 K) can disrupt melatonin production, making it harder to fall asleep. Therefore, it's better to use warmer light in the evening.
• Warmer light colors help relax the eyes, while cooler light colors can be more energizing, which is important for daylight conditions.
4. Color perception :
• Warm light can make colors appear more yellow , while cool light can make colors appear more white or blue . In some applications, such as illuminating art or products, the right light color can ensure that colors are displayed accurately.

Applications of light color

1. Living areas :
• In living areas such as living rooms , bedrooms and dining rooms , warm white light (2,700 K – 3,000 K) is often used to create a cozy and relaxing atmosphere.
2. Workspaces :
• In kitchens , offices and workspaces , cool white light (4,100K – 5,000K) is useful as it increases brightness and promotes productivity.
3. Commercial spaces :
• In shops and showrooms , a neutral white or cool white light can enhance the colours of products and create an energetic atmosphere.
4. Outdoor lighting :
• Light above 5,000 K , such as daylight white or cool bluish light, is often used for outdoor lighting , because it is bright and vibrant, and illuminates the environment well without disturbing the natural look of daylight.

Summary

Light color is measured in Kelvin (K) and ranges from warm light (approximately 2,700 K) to cool white light (over 5,000 K). The choice of light color influences the ambiance , productivity , and health of a space. Warm light is often used in living spaces for relaxation, while cool white light is better suited for workspaces where clarity and concentration are important. The right type of light can also enhance color perception and improve the aesthetics of a space or product.