Basic knowledge of indoor lighting design (4) illuminance, brightness, glare, shadow, color display, etc

Here are some of the basics of interior lighting design organized for you by Esso Lighting Design Consultants

Many projects seem to brighten up the space, but there is always some uncomfortable feeling, so we need to pay special attention to the quality of lighting, high-quality lighting effect is the basis for obtaining a good comfortable light environment, illumination, brightness, glare, shadow, color display and other factors in the lighting environment are the key to affect the high-quality lighting effect. Therefore, the ideal light environment can only be obtained if the above elements are handled correctly.

1. Illuminance

Illuminance refers to the luminous flux value per unit area of the illuminated object, and the unit is lx (lux) which is an indirect indicator that determines the brightness of the illuminated object. Increasing illuminance in a certain range can improve visual function. Proper illumination is conducive to protecting eyesight and improving work and study ability. When determining the size of the lighting required for the lighting environment, the size of the object to be observed and its contrast with the brightness of the background must be taken into account to ensure the basic requirements of vision.

2. Brightness

Brightness refers to the luminous intensity cd/m2 per unit projection area of the luminaire in the direction of the line of sight. It represents the intuitive perception of the brightness of an object by human vision. In interior lighting design, care should be taken to ensure proper brightness distribution. In an indoor environment, if the brightness of the other person changes too much, the eyes are forced to go through a process of adaptation when people's vision shifts from one place to another. If this adaptation process is repeated too much, it can lead to visual fatigue. The brightness of the background environment should be as low as possible to the brightness of the object being observed. When the brightness of the observed object is 3 times the height of the background environment, better visual clarity can usually be obtained, that is, the reflection ratio of the background environment and the observed object should be controlled in the range of 0.3-0.5.

3. Glare

Glare refers to visual discomfort or vision loss caused by visual discomfort or vision loss. For example, looking at the sun during the day because it is too bright for the eyes to adapt to and can't open their eyes. Another example is that when looking at street lights at night, the bright street lights are lined against the dark night sky, and the black and white contrast is too strong, and it also feels dazzling. In interior lighting design, glare should be avoided as much as possible.

Glare comes in two forms: direct glare and reflected glare. The glare caused by the direct entry of a high-brightness light source into the human eye is called direct glare; The glare caused by the reflection of a light source into the human eye through a glossy surface is called reflected glare. Therefore, in the interior lighting design, in addition to limiting direct glare, attention should also be paid to avoiding the reflection glare caused by high-gloss decorative materials (such as mirrors, stainless steel, etc.).

The following measures can be taken to control the occurrence of glare:

(1) Limit the brightness of the light source or reduce the brightness of the surface of the lamp. The light source can be covered with frosted glass or opalescent glass or translucent diffusing material.

(2) Lamps with large protection angles can be used. What design means to us.

(3) Arrange the position of the lamps reasonably and choose the appropriate hanging height. When the hanging height of the lamp is increased, the glare effect decreases; If the angle between the lamp and the person is greater than 45°, the glare phenomenon is greatly reduced. Of course, this method is usually limited by the height of the floor of the house, and the lamps that are too high are not conducive to the lighting of the working surface, so they should usually be combined with the lamps with large protection angles.

(4) Appropriately increase the brightness of the environment and reduce the brightness contrast, especially the brightness contrast between the working object and the directly adjacent background.

(5) Use matte material.

(6) Low-brightness specular reflectors, etc.

(7) Use protective corner lamps that are suitable for the requirements of the work area.

4. Color rendering

There are many types of light sources, and their spectral properties are different, so the same object will appear different colors under the illumination of different light sources, that is, the color rendering of the light source. Generally speaking, people are accustomed to distinguishing colors in sunlight, so when more color rendering, the sun or an artificial light source close to the solar spectrum is usually used as the standard light source, and the color rendering index is set to the closer the light source is to the standard spectrum, the higher the color rendering index. It is suitable for places with different color rendering indexes. Where it is necessary to distinguish colors correctly, mixed light from various light sources can be used.

Studies have shown that the comfort of color temperature is related to the level of lighting, and at very low lighting, comfort. The light color is the low-temperature light color close to the flame; In low or moderate light, the comfortable light color is close to dawn and dusk; In high illumination, the comfortable light color is close to the midday sun or the blue hot sky. Figure 5-5 shows that when designing indoor spaces with different environmental atmospheres, appropriate color temperature and illumination should be selected.

5. Shadows

Shadows appear at or near work objects, which can cause optical illusions, increase visual burden, and affect work efficiency, and should be avoided in design. Diffuse the lamp or adjust the position of the light source to increase the number of light sources. Of course, if the shadows are used well, they can also create a different visual effect.

7. Strobe

In AC circuits, the luminous flux emitted by the light source fluctuates with the change in voltage, so visual distortion occurs when observing moving objects, which can easily cause illusions and even cause accidents. Eliminating the flicker effect is primarily about improving power supply design.

The above is the basic knowledge of illuminance, color temperature, glare, and strobe in indoor lighting design, if you want to know more, you can also consult us directly. ESSO Lighting Design is committed to hotel lighting design, office lighting design, catering lighting design, club villa lighting design, marketing center lighting design, commercial store lighting design, cultural tourism night scene and other design consulting projects, advocating a healthy and harmonious light environment.