Normally expressed as watts per millimetre squared, this is the power per unit area on a surface through which radiation passes at the radiating surface of light source or at the cross-section of an optical waveguide
The measurement of radiant flux incident on a surface, in watts (energy per unit time)
the rate at which radiant energy arrives at a specific area of surface during a specific time interval This is known as radiant flux density A typical unit is W/m2
-The amount of radiative power impinging a surface, divided by the area of this surface Irradiance is often measured in the units watts per square meter
Irradiance is a measure of radiometric flux per unit area Irradiance is typically expressed in W/cm2 (watts per square centimeter)
The integrated radiation arriving at a surface at all wavelengths, expressed in SI units of watts per square meter In Radiance, only visible radiation is considered, but units of radiance and irradiance are still used; they are divided into separate components for the red, green, and blue spectral ranges (Compare to illuminance )
The radiant energy that passes through a unit horizontal area per unit time coming from all directions above it The irradiance is defined by where is the radiance, the zenith angle, and the infinitesimal solid angle The rate at which radiation is incident upon a unit area
A measure of the amount of light energy incident on a unit area of surface per unit time Measured in Watts per square meter
The intensity of a light wave, commonly denoted by the letter I The irradiance is the power per unit area carried by an electromagnetic wave The time averaged value of the magnitude of the Poynting vector
That which irradiates or is irradiated; luster; splendor; irradiation; brilliancy
the energy flux density of electromagnetic radiation impinging on a real or imaginary surface
The total radiant flux received on a unit area of a given real or imaginary surface Also called the radiant flux density
The density of the radiant flux that is incident on a surface per unit of wavelength
Radiant power incident per unit area upon a surface Note: Irradiance is usually expressed in watts per square meter, but may also be expressed in joules per square meter (188) Deprecated synonym power density