Floodlights Show Objects In Different Planes And Components

Floodlights not be "submerged in the ocean of light". By using more or less illumination or shadows in adjacent areas, flood lighting should be able to show the undulating contours of different planes and components of the object.

Should take into account the following points:

1, the incident angle

It is the shadow that will stand up and down, so the lighting should always be able to provide surface imaging, with positive angles on the facade of the light will not form a shadow, and the surface is shown as flat.

The shadow size depends on the surface relief and the incident angle of the light. The average illumination angle should be 45 °. If the ups and downs are minimal, this angle should be greater than 45 °.

2, the direction of lighting

In order for the surface illumination to look balanced, all shadows should be projected in the same direction, and all lamps that illuminate the surface in a projection area should have the same direction of projection. For example, if two lights are symmetrically aimed at the vertical direction of a surface, the shadows will be reduced and may be confused. So there may not be able to see the surface ups and downs. However, large protrusions can produce large, dense shadows. To avoid breaking the integrity of the facade, it is advisable to weaken the shadows by providing weaker illumination at an angle of 90 ° to the main light (see Figure 2).

3, viewing angle and lighting direction

In order to see the shadows and surface ups and downs, the lighting direction should be different from the viewing direction, the two directions should be at least 45 °. However, for monuments that can be seen from several places, it is not possible to strictly adhere to this rule, and the main observation points should be chosen, giving priority to this observation in lighting design.

4, floodlights

position

In urban contexts, it is often not possible to install floodlights in an ideal location. Should be adjusted at the scene based on the initial design of the lighting design in order to take into account the physical limits of the location and achieve the most satisfactory solution, such as taking into account the appearance of the fluorescent lamp, glare, maintenance and adjustment of the entrance.

Beam range

The width of the beam produced by the floodlight may be larger or smaller depending on the position adjustment of the optical system and the light source in the lamp. Conventionally, the beam range of the floodlight is determined by the direction of the luminous intensity equal to 50% of the peak luminous intensity in the axial direction of the beam.

The beam range of the circular symmetrical floodlight is constant on each face, and the beam range of the rectangular floodlight is usually oval, which is determined by the two values corresponding to the two symmetry planes.

In some applications, the light beam used is asymmetrical in the case of peak light intensity. In this case, the beam range is equal to 50% of the light intensity determined by the two half angles.

5, light intensity section curve

Due to the narrow beam range of many floodlights, the curves in polar coordinates in Figure 3 can not be read or inaccurate. In general, if XY is used, where the vertical axis OY represents the illuminance, the horizontal axis OX represents the angle of the beam. In most floodlights, the light source that transfers the optical system will change the shape of the distribution curve (beam range, light intensity, and symmetry).

6, application examples

(1) column tower

In order to be able to see the circle of the tower, the width of the tower should be constantly changing the brightness. However, the fiber should remain on the vertical line. The floodlights are arranged in accordance with Figs. 5A and 5B. The change depends on the ratio of the distance between the object to the object and the diameter of the tower.

When the ratio is high, that is, when the narrow tower is illuminated by a distant floodlight, it is appropriate to arrange two floodlights according to Fig. 5A. When the floodlights are installed in the vicinity of the building, three sets of floodlights should be arranged according to Figure 5B for the low tower, with an angle of about 120 ° from each other.

When you can only see a large diameter column from one direction, you may have two effects. It is possible to create an illuminated central area between two dark areas (Figure 5B / 5D / Figure 5E) or to reverse the arrangement depending on the characteristics of the building background.