Vertailuvalonlähde

Vertailuvalonlähde, which translates to "comparison light source" in English, is a term used in metrology and optical engineering. It refers to a controlled and standardized light source whose properties, such as spectral distribution, intensity, and color temperature, are precisely known and stable. This known source is used as a reference point for calibrating or comparing other light sources.

The primary function of a vertailuvalonlähde is to provide a benchmark for accurate measurements. When evaluating the performance or characteristics of an unknown light source, it is compared against the vertailuvalonlähde. This comparison allows for the determination of deviations or similarities in properties like color rendering, luminous flux, or spectral output. For example, in the lighting industry, a newly developed LED might be compared to a standardized incandescent or a high-quality LED vertailuvalonlähde to assess its color quality and efficiency.

These sources are often developed and maintained by national metrology institutes or specialized calibration laboratories. They are designed to be highly reproducible and possess well-defined physical characteristics, often traceable to fundamental physical constants or international standards. The stability over time is crucial, requiring careful control of operating conditions and periodic recalibration. The concept is fundamental to ensuring consistency and accuracy in optical measurements across different instruments and locations.