Color temperature: expressed in absolute temperature K, is to heat a standard black body, when the temperature rises to a certain level, the color begins to change from red-light red-orange-yellow-white-blue-white-blue, using this light color When the light color of a light source is the same as that of a black body at a certain temperature, we call the absolute temperature of the black body at that time as the correlated color temperature of the light source.

Color rendering index (Ra): A parameter that measures the ability of a light source to display the true color of the illuminated object. The higher the color rendering index (0-100), the closer the color reproduction of the light source to the natural primary color. Greater than 90 is excellent, and places with extremely high requirements for color identification, such as printing, printing and dyeing product inspection, etc. 80-90 is very good, color TV broadcast, display lighting. 65-80 is better for indoor lighting. 50-65 is medium, outdoor lighting. Less than 50 is poor, places with low color requirements, such as parking lots, freight yards, etc.

Luminous flux (lumens Lm): Indicates how much the luminous body emits. Lumen is the unit of luminous flux. The more luminous, the greater the number of lumens.

Luminous efficiency: the ratio of the luminous flux emitted by the light source to the electric power consumed. The unit is lumen per watt (Lm/W).

Average life: Also known as rated life, it refers to the number of hours that a batch of lamps is lit to half the number of damaged ones.

Luminous Intensity: The luminous flux per unit solid angle. Unit: cd

Illuminance: Illuminance is used to describe the degree of illumination on the illuminated surface (working surface), usually expressed by the luminous flux received per unit area, in lux (lx) or lumens per square meter (lm/m2).

Brightness: Brightness is a physical quantity used to indicate the intensity of light (or reflection) on the surface of an object. The ratio of the light-emitting intensity of the light-emitting surface of the object being viewed in the direction of sight to the projected area of the light-emitting surface in the direction perpendicular to the direction is called the light-emitting surface. The surface brightness in candela per square meter (cd/m2).

Luminous efficiency: usually referred to as luminous efficiency, is an optical quantity that describes the quality and economy of the light source. It reflects the amount of luminous flux radiated by the light source while consuming a unit of energy. The unit is lumens per watt (lm/w) Beam angle: yes Refers to the angle of the light of the lamp and the angle of the lamp cup. There are three common types: 10°, 24°, and 38°.

Color rendering: The color rendering index of the light source and the illuminance together determine the visual clarity of the environment. There is a balance between illuminance and color rendering index. The results obtained from extensive experiments are: lighting an office with a lamp with a color rendering index Ra>90 is more satisfactory in terms of appearance than an office lit with a lamp with a lower color rendering index (Ra<60). The value is more than 25% higher.

Light environment: Light environment is people's psychological feeling of light in a certain visual space. A good light environment produces a good visual experience, which directly affects people's physical and mental health. When people consider creating a good light environment, they should also consider the issue of energy saving. The concept of green lighting is how to reduce the release of mercury and how to save the limited energy for human survival.