Definition of LED luminaire parameters
1,Luminous flux: a measure of light derived from the effect of radiation on a standard photometric observer. The symbol of this quantity is ф, the unit is lumen (LM), 1lm=1cd• 1SR.
①Luminous flux is the amount of light energy arriving, leaving, or passing through a surface per unit time.
②Luminous flux is the ratio of light emitted by a bulb.
2，Luminous intensity: It refers to the luminous flux emitted by the light source in a unit solid Angle in a specified direction, that is to say, the optical flux radiated by the light source to a certain direction in space. The symbol is denoted by I, and the SI unit is candela, short for CD. The light intensity represents the radiation capacity of the light source in different directions. Colloquially, the luminous intensity is the intensity of the light that the illuminant places emit.
3,Luminance: It refers to the luminance (reflective body) surface luminescence (reflective) strength of the physical quantity. The human eye observes the light source from a direction, and the ratio of the light intensity in this direction to the area of the light source "seen" by the human eye is defined as the brightness of the light source unit, that is, the luminescence intensity on the unit projected area. Brightness is denoted by the symbol L, and the unit of brightness is candela per square meter (CD per square meter).
The brightness of the light source is related to the surface area of the luminous body. In the case of the same light intensity, the luminous area is large and dark, whereas it is bright.
4,Illumination intensity: It is a physical term that refers to the luminous flux of visible light received per unit area. Illuminance [1], in Lux or Lx. A quantity used to indicate the intensity of light and the extent to which the surface area of an object is illuminated.
5,Luminous efficiency: The ratio of the total luminous flux emitted by a light source to the electrical power (watts) consumed by the light source.
The higher the luminous efficiency value, the stronger the ability of the lighting equipment to convert electric energy into light energy, that is, in the case of providing the same brightness, the stronger the energy saving of the lighting equipment; Under the same power, the illumination of the lighting equipment is stronger, that is, the brightness is greater.
6,Color temperature: It is the most common indicator to indicate the spectral quality of a light source. It's usually denoted by Tc. The color temperature is defined by the absolute blackbody, the radiation of the absolute blackbody and the radiation of the light source in the visible area are exactly the same, and the temperature of the blackbody is called the color temperature of the light source. Low color temperature light source is characterized by the energy distribution, red radiation is relatively more, usually called "warm light "; When the color temperature increases, the proportion of blue radiation in the energy distribution increases, often called "cold light".
7,Color index coefficient:When there is little or no main wave reflected by the object under the reference light source in the light source spectrum, the color will produce obvious color difference. The greater the degree of color difference, the worse the color rendering of the light source. Color rendering index coefficient (Kau FMAN) is still a common method to define color rendering of light sources.
8,Average life: It is defined as the number of hours of light in a batch when 50% of the lights fail to work.
1,Luminous flux: a measure of light derived from the effect of radiation on a standard photometric observer. The symbol of this quantity is ф, the unit is lumen (LM), 1lm=1cd• 1SR.
①Luminous flux is the amount of light energy arriving, leaving, or passing through a surface per unit time.
②Luminous flux is the ratio of light emitted by a bulb.
2，Luminous intensity: It refers to the luminous flux emitted by the light source in a unit solid Angle in a specified direction, that is to say, the optical flux radiated by the light source to a certain direction in space. The symbol is denoted by I, and the SI unit is candela, short for CD. The light intensity represents the radiation capacity of the light source in different directions. Colloquially, the luminous intensity is the intensity of the light that the illuminant places emit.
3,Luminance: It refers to the luminance (reflective body) surface luminescence (reflective) strength of the physical quantity. The human eye observes the light source from a direction, and the ratio of the light intensity in this direction to the area of the light source "seen" by the human eye is defined as the brightness of the light source unit, that is, the luminescence intensity on the unit projected area. Brightness is denoted by the symbol L, and the unit of brightness is candela per square meter (CD per square meter).
The brightness of the light source is related to the surface area of the luminous body. In the case of the same light intensity, the luminous area is large and dark, whereas it is bright.
4,Illumination intensity: It is a physical term that refers to the luminous flux of visible light received per unit area. Illuminance [1], in Lux or Lx. A quantity used to indicate the intensity of light and the extent to which the surface area of an object is illuminated.
5,Luminous efficiency: The ratio of the total luminous flux emitted by a light source to the electrical power (watts) consumed by the light source.
The higher the luminous efficiency value, the stronger the ability of the lighting equipment to convert electric energy into light energy, that is, in the case of providing the same brightness, the stronger the energy saving of the lighting equipment; Under the same power, the illumination of the lighting equipment is stronger, that is, the brightness is greater.
6,Color temperature: It is the most common indicator to indicate the spectral quality of a light source. It's usually denoted by Tc. The color temperature is defined by the absolute blackbody, the radiation of the absolute blackbody and the radiation of the light source in the visible area are exactly the same, and the temperature of the blackbody is called the color temperature of the light source. Low color temperature light source is characterized by the energy distribution, red radiation is relatively more, usually called "warm light "; When the color temperature increases, the proportion of blue radiation in the energy distribution increases, often called "cold light".
7,Color index coefficient:When there is little or no main wave reflected by the object under the reference light source in the light source spectrum, the color will produce obvious color difference. The greater the degree of color difference, the worse the color rendering of the light source. Color rendering index coefficient (Kau FMAN) is still a common method to define color rendering of light sources.
8,Average life: It is defined as the number of hours of light in a batch when 50% of the lights fail to work.
