What is light
Light consists of photons, also called light particles. They travel in waves and transmit energy impulses. Light is created when energy is converted. When visible light is emitted, this is also called luminescence. How bright and colorful the human eye can perceive a light depends on the wavelength of the radiation and the intensity with which the radiation hits the retina.
Short wavelengths are termed ultraviolet and longer waves are termed infrared.
What is the light flux
The light flux is measured in lumens (abbreviation lm). The unit lumen is an internationally standardized unit of measurement for the light flux of a light source. It indicates how much light is emitted by a radiation source in all directions, so it measures the total light output. The lumens of a luminaire therefore provide information about its brightness. Identical luminaire types can be compared by their wattage.
Different lamps, however, produce different amounts of light and therefore cannot be compared by wattage. To compare the high intensity of different lamps, luminous flux must be used.
The value Lumen does not take the brightness sensation into account. The perception of brightness is additionally influenced by the beam angle and the design of a luminaire. Also, the color temperature of the illuminant and the condition of the environment play a role in the perception of brightness. Usually, the lumens can be tested through an integrating sphere. The integrating sphere is a simple, yet often misunderstood, device for measuring optical radiation. An integrating sphere’s function is to spatially integrate radiant flux (light).
Post time: Jul-26-2022