What is color temperature?
The color temperature of a lamp determines whether the light gives a warm or cool impression. The color temperature is given in Kelvin and can be assessed on a scale. The lower the color temperature, the warmer and darker the light appears. The higher the color temperature, the cooler and brighter the light appears.
The color temperature influences the room atmosphere. For living rooms, a lower color temperature is preferred, for laboratories or factories, light with a higher color temperature. The scale below shows the color temperature and its three ranges: Warm white, neutral white and daylight white.
Color temperature can be measured with a colorimeter. Besides color temperature, the color rendering index is also significant for the spatial atmosphere.
What is the color rendering index?
The color rendering index, abbreviated CRI (Color Rendering Index) or RA (General Reference Index) tells us what quality the emitted light has.
When an object is illuminated, it emits colors. The color emitted is not only determined by the color of the object itself, but also by the light source. The illuminant emits different wavelengths that are absorbed or reflected by the illuminated object. Those wavelengths that match the illuminated object are reflected, the rest is absorbed. The color rendering index therefore depends on which wavelengths are emitted by the light source.
Natural sunlight has an RA value of 100, which is also the highest RA value. The closer the RA value is to 100, the higher the quality of the lighting.
What is the reflection factor?
The reflection factor indicates the percentage of the luminous flux that hits a surface that is reflected. Depending on the nature of the illuminated surface, the light is reflected, absorbed or transmitted.
If light is reflected, it is reflected back. Mirrors have a reflectance of 1. Light surfaces have a value close to 1, dark surfaces have a value below 0.1. In a room with dark walls, more light is needed than in a room with light walls to create sufficient illuminance on the working plane.
Post time: Aug-31-2022