Strahlungsintensität

Strahlungsintensität, often translated as radiation intensity, is a fundamental concept in physics and engineering that quantifies the power radiated from a source per unit solid angle. It describes how concentrated the radiation is in a particular direction. The unit for strahlungsintensität is Watts per steradian (W/sr).

This quantity is crucial for understanding and characterizing various forms of radiation, including electromagnetic waves like light and radio waves, as well as particle beams. For a point source emitting uniformly in all directions, the intensity would be constant regardless of direction. However, many real-world sources exhibit directional properties. For instance, a spotlight has a high strahlungsintensität in the forward direction and a low intensity in other directions.

Strahlungsintensität is distinct from radiant flux (total power emitted), radiant exitance (power emitted per unit area), and irradiance (power incident per unit area). While related, strahlungsintensität specifically focuses on the angular distribution of radiated power. It is a key parameter in applications such as antenna design, lighting engineering, and the study of stellar radiation. Calculating or measuring strahlungsintensität helps predict the coverage and strength of radiation in different spatial regions.