Luminous Intensity Converter

Luminous intensity is a fundamental concept in the field of optics and lighting design, representing the amount of visible light emitted or radiated in a specific direction. It plays a crucial role in lighting design, ensuring that the brightness of a light source is accurately characterized and standardized.

The unit of luminous intensity is the Candela (cd), but there are several other units used across different regions and historical contexts. To make sense of these units and facilitate conversions, a Luminous Intensity Converter tool proves invaluable.

  • Candela (cd): The candela is the standard unit of luminous intensity in the International System of Units (SI). It measures luminous power per unit solid angle emitted by a light source in a particular direction.
    Conversion Factor: 1 cd = 1 cd (Base Unit)

  • Candle (c): The candle (or candlepower) unit is an older unit of luminous intensity. In 1948, the unit candela replaced candlepower. One candlepower unit is about 0.981 candela but in general modern use, a candlepower now equates directly (1:1) to the number of candelas.
    Conversion Factor: 1 cd = 1 c

  • German Candle (c): Similar to the standard candle, the German candle is another historical unit of luminous intensity. It was used in Germany before the adoption of the candela.
    Conversion Factor: 1 cd = 0.95 c (german)

  • UK Candle (c): The UK candle is yet another variant used in the United Kingdom. Like other candle units, it has been largely replaced by the candela in modern scientific and technical contexts.
    Conversion Factor: 1 cd = 0.96 c (UK)

  • Hefner Candle (HK): The Hefner candle, named after Friedrich von Hefner-Alteneck, is a historical unit used in Germany. It was based on the light emitted by a lamp burning amyl acetate.
    Conversion Factor: 0.9 cd = 1 HK

  • Carcel Unit: The Carcel unit is an obsolete French unit of luminous intensity, defined by the light produced by a Carcel lamp burning a standard quantity of oil.
    Conversion Factor: 9.61 cd = 1 Carcel unit

  • Lumen per Steradian (lm/sr): An equivalent unit to the candela. The total luminous flux of a light beam is 1 lumen when its intensity is 1 candela, and its space angle is 1 steradian. Therefore, 1 lumen per steradian is equivalent to 1 candela.
    Conversion Factor: 1 cd = 1 lm/sr

In conclusion, a Luminous Intensity Converter tool is a valuable resource for professionals in lighting design, researchers, and anyone working with diverse units of luminous intensity. Understanding the historical and regional variations in units allows for precise conversions, ensuring accurate communication and collaboration in the field of optics and lighting.