The relationship between illuminance and brightness detected by illuminometer and luminometer
The relationship between illuminance and brightness detected by illuminometer and luminometer:
In our daily lives, light is always in contact, and when it comes to light, it must be related to illuminance and brightness.
So what is the difference between brightness and illuminance?
Illuminance concept under illuminometer detection:
In short, the total amount of light emitted by a bulb (luminous flux) enters a certain surface layer at a certain intensity - the intensity of light (luminous intensity), and then the luminosity of that surface layer can be measured.
Luminance concept measured by a luminometer:
Luminance refers to the physical quantity of the brightness (reflection) intensity on the surface of a luminescent body (reflector). The human eye observes a light source from one direction. The ratio of the light intensity in this direction to the "visible" light source area of the human eye is defined as the brightness of the light source unit, that is, the luminous intensity of the expanded area of the unit. When we stand at a certain position to observe the surface, we see the brightness level (brightness) of the surface.
In summary, illuminance is an objective parameter that measures the total amount of light that actually reaches a surface using instruments; Luminance refers to the level of light emitted or reflected by an object as perceived by the human eye.
In addition, regardless of whether the surface is black or white, whether it is wood or stone, the illumination value is the same. The surface will reflect light, which may be specular or diffuse. The refraction of light occurs in many directions in space.
How does illumination and brightness affect our lives?
It can be said that all indoor space lighting should evaluate the horizontal lighting of the working surface, but we should pay attention to the adaptability of lighting and color temperature. For example, in our work, changing the color of office lighting is not enough, but we also need to pay attention to lighting.
High illumination and low color temperature can make people feel very hot, while low illumination and high color temperature can make people feel gloomy and tired, leading to a decrease in work efficiency.
Related experiments have shown that at the same time, with the increase of illumination level, the satisfaction of workers will significantly increase for 300lx-500lx; The satisfaction level of the above 500lx workers is basically saturated, and the improvement of lighting level will not significantly change the workers' evaluation of the lighting environment. Therefore, the latest office lighting standard in China is 300 lx-500lx, which is also the most suitable illuminance for working surfaces.
In addition, in the dining space, there must be sufficient lighting in the indoor environment and dining table to meet the basic dining needs of customers. According to the recommendations of the China Lighting Association in the Chinese architectural lighting design standards, it is advisable to have a dining table lighting of 200 lx sheets.
Chinese architectural lighting design standards require that the illumination at the 00.75m level of a Chinese restaurant should not be less than 200lx, and there should be no less than 100 Western restaurants with lx. The illumination values for each spatial location should be consistent.
