Luminous flux: the sum of the amount of light emitted by a light source per second, which is used to indicate the amount of light emitted by a lamp, that is, the amount of light emitted. The universal symbol Ф indicates that the unit is lumen (Lm).
Luminous intensity: The luminous flux emitted by a light source in a unit solid angle in a given direction is called the luminous intensity of the light source in that direction, which is often expressed by I and the unit is Candeira (cd).
Illuminance: Illuminance is the luminous flux of the light source shining on the unit area of the illuminated object. E is often used to express it, and the unit is lux (lx) or lumen square meter (lm/m2).
Brightness: the intensity of light reflected from a certain direction, that is, the intensity of light reflected from a certain direction in a unit area. Symbol l, unit cd/ m2. Illuminance indicates the incidence in a unit area.
The amount of light. Brightness is the intensity of reflected light from an object seen by the eyes from a certain direction.
Color temperature: When a standard black body is heated, its color changes from dark red to light red, then to orange, white and blue with the increase of temperature. According to this characteristic of blackbody, when the light emitted by the light source
At the same time, we call the absolute temperature of the black body the color temperature of the light source, which is expressed by the absolute temperature K. The color temperature is below 3300K, and the light color is red.
With a warm feeling; The color temperature exceeds 5300 K, and the light color is blue, giving people a cold feeling. Usually, in areas with high temperature, people usually use light sources with color temperature higher than 4000K, and the temperature is.
In lower areas, more light sources below 4000K are used.
Color rendering index: a parameter to measure the ability of a light source to display the true color of an illuminated object. Based on the standard light source, its color rendering index is set to 100, and the color rendering indexes of other light sources are all lower than 100. Colored finger
The larger the number (0- 100), the closer the color reproduction of the light source is to the natural primary colors. The color rendering index is indicated by the symbol Ra.
Light efficiency: the efficiency of light source to convert electric energy into visible light, that is, the light emitted by light source when it consumes each watt of electric energy. The higher the value, the higher the efficiency of the light source. From an economic point of view, light efficiency
Is an important parameter. Symbol η, unit: lumens per watt (Lm/w).
Average life: refers to the number of hours when a batch of lights are on and 50% of them are damaged. Unit: hours.
Luminous flux maintenance rate: the light output of the lamp decreases gradually with the increase of working time. When the lamp is lit 100 hour, the percentage of the luminous flux of the lamp at a fixed time relative to the initial luminous flux. It should be called ...
The luminous flux maintenance rate of the fixed time.
Glare: Glare is a dazzling effect caused by improper brightness distribution or excessive brightness change, which can be divided into two forms: glare and reflected glare. Direct glare refers to the light source.
The emitted light directly enters the human eye; Reflective glare refers to the light reflected on smooth walls, tables, mirrors and other objects penetrating the human eye. Strong glare will make the indoor light uncoordinated,
It makes people feel uncomfortable. In severe cases, they will be dizzy and even temporarily blind.
Stroboscopic effect: With the periodic change of voltage and current, the luminous flux of induction fluorescent lamp also changes periodically, which makes human eyes have the illusion of not rotating when observing rotating objects, which is called stroboscopic effect.
Yes The stroboscopic effect will also make people feel uncomfortable and reduce the labor productivity of workers. Electronic fluorescent lamp will not produce stroboscopic effect and is a product of "green lighting project".
1. How to classify energy-saving lamps?
Answer: Energy-saving lamps can be divided into single-ended fluorescent lamps (intubation lamps) and self-ballasted fluorescent lamps (electronic lamps).
Single-ended fluorescent lamps can be detached from lamps and used in specially designed lamps and lanterns. With the help of the control circuit integrated with the lamp, the design purpose of decorating or optimizing the lighting function is achieved. There are two kinds of lamp holders: two feet and four feet. Two-pin lamp holder includes upconverter and RF interference suppression capacitor, while four-pin lamp holder has no circuit components.
Self-ballasted fluorescent lamp comes with a complete set of control circuits such as ballast and starter, and Edison screw lamp holder or socket lamp holder is installed. The circuit is generally encapsulated in a shell, and the control circuit in the lamp assembly is mainly a high-frequency electronic ballast. This integrated compact energy-saving lamp can be directly installed on the lamp holder of standard incandescent lamp to directly replace incandescent lamp.
2. What is the relationship between luminous flux and power? Comparison of luminous flux of different kinds of lamps with the same power? What is the relationship between luminous flux and illuminance?
A: Generally speaking, the higher the power of the same type of lamp, the greater the luminous flux. See the instruction for the luminous flux of various types of lamps.
The illumination of a high-brightness light source in the same place must be high, but there is no necessary relationship between luminous flux and illumination. For a certain light source, the illumination of the illuminated surface depends on the shape, size, reflection efficiency and matching with the lamp, as well as the height, room wall reflectivity and many other factors.