With the rapid development of China's economy and the improvement of the quality of the people, sports have gradually become an important part of people's lives. The construction of stadiums and sports lighting also continues to develop. Because sports are affected by many factors such as exercise space, direction, range, speed, etc., there are more and more stringent requirements than general lighting. Different sports have different sports characteristics, so the requirements for lighting are also very different. This article focuses on issues related to indoor tennis court lighting.

1. Reflectance of walls, ceilings and ground

Tennis requires high visual perception requirements and usually has a high velocity at a short distance. Therefore, the ball's operation is judged correctly only for a very limited time. In addition, athletes move quickly in all directions. The athletes and the ball are mainly faced with the floor and the back wall, and the highball is also seen when facing the ceiling. Therefore, there must be a strong illuminance contrast between the player and the ball and its background. Large differences in illuminance across the entire floor and wall area hinder perception. Therefore, it must be avoided. From this point of view, it is not appropriate to use glossy materials for the decoration of these surfaces. Similarly, the markings on the ground should not be glossy. It is advisable to make the ceiling and wall plain. Strong contrast between line and surface formed by the construction or interior decoration of the building should be avoided. The indication of the size within a limited range of activities can help to determine the direction and easy to estimate the distance. Barriers or enclosures may be considered here for blocking the movement of the ball. In order to obtain a generally acceptable brightness ratio, the wall reflection ratio should be between 0.2 and 9.6. It is advisable to make the rear wall a low reflectance value. Colored walls are preferable to grey walls because of the contrasting colors that make the ball easier to see. It should generally be chosen so that the ball has good color and brightness contrast with its background.

In order to limit the brightness contrast between the light source and the top grid, the reflectance of the ceiling should be higher than 0.6, and a floor reflection ratio of at least 0.25 is desirable.

2. Natural lighting and windows

Indoor tennis does not require natural light and look outside, and most of the walls have glass windows that make it difficult to perceive. If natural light is emitted, the athletes will be able to concentrate on the competition under stable lighting conditions with good artificial lighting design. If the window in the gym is installed for other reasons, the following points occur:

- Direct sunlight is usually harmful and must be avoided.

- When using natural light, even in the absence of direct sunlight or visual contact with the outdoors, measures should be taken to prevent athletes from causing interference in areas of high brightness.

- The windows on the wall behind the bottom line must be avoided.

- Natural light coming in from nearby areas can also be annoying.

- If sunlight and dawn are diffused by the frosted glass, no glare is guaranteed. But the result is the opposite, and the conditions have become even less favorable.

- Use large-area skylights on the tennis courts, and obtain acceptable brightness ratios when they are properly arranged and properly shaded.

- When using natural light entering through a roof or side sill, it has an effect on the overall environment of the room. Special consideration must be given to floor reflections.

Generally, in the galleries of the inflatable structures, natural light is no problem due to the low light transmittance of the shell material and the large area, and the natural light enters the hall through the shell.

3. Artificial lighting

3.1 General requirements for lighting systems

Most of the roofs on the field appear frequently in the athlete's field of vision. Therefore, it should be kept as uncluttered as possible, and in particular, high-brightness light sources should be avoided on the ceiling. The background brightness of the ball being watched should be as uniform as possible.

From the lighting engineering point of view, there are two ways to achieve this goal: First, use direct lighting from both sides of the site; second, use a light-emitting ceiling. The luminous ceiling can be composed of a diffuser ceiling grille with a lamp mounted on it or a grille with a single light colored and matt surface. Light can be directly shot on the ceiling. The direct lighting method can use straight tubular fluorescent lamps or high pressure gas. Discharge lamp. In order to obtain the appropriate illumination level at the end of the site, the luminaire must go beyond the bottom line. The side lighting system can be supplemented by partial lighting above the ceiling. This method is usually the most common from a lighting and economic point of view. In the case of a light-emitting ceiling, the brightness of the translucent diffuser may be too high if this system is provided with a high illumination level. To prevent this from happening, the ceiling may be blocked by a vertical shutter, if the indirect illumination is more shielded When it is difficult and the utilization factor is lower than that of direct lighting, indirect lighting is usually adopted when it is impossible to use other lighting devices due to architectural reasons, such as in an inflatable structure or in a hall with a shrinkable roof. Due to the low utilization factor of indirect lighting, the effective ceiling area for direct illumination of the galleries with high efficiency light source and high light output ratio in the galleries of inflatable structures is usually much larger than that of conventional pavilions, which means a lower ceiling brightness. Upon request, the entire site can reach a given level of illumination. If possible, it is recommended that indirect lighting should be supplemented by the direct lighting section, which will improve the stereoscopic effect, which helps to visualize and increase the overall effectiveness of the device.

3.2 Uniformity of illumination

The average horizontal illuminance on the ground is usually used as the basis for the recommended illuminance. One reason for this is that the concept of illumination is easy to apply in practice. However, vertical illuminance is also important.

The acceptable horizontal illuminance values ​​are:

1. Match 750 lux

2. Training 500 Lux

At these illuminance levels, direct illumination with proper glare control will result in acceptable illuminance on the vertical plane.

3. Entertainment 300 lux

All of these values ​​are used values. The allowable value of the light attenuation of the lighting device depends on the local conditions. The initial illuminance value needs to be about 1.2 to 1.5 times the illuminance value used. The horizontal illuminance evenness of the ground is the ratio between the average illuminance and the minimum illuminance and must be no more than 1.3 (for competition) and no more than 1.5 (for training and entertainment) in the competition area. When the illuminance is higher than the above-mentioned level, visual conditions can be improved, and the provided quality requirements can maintain uniformity, glare control, and brightness ratio. There should be an auditorium for tennis at this time.

3.3 Selection of light sources and shields

(1) Straight tube fluorescent lamps are most suitable for designs where the light source is arranged on the side of the site or above the lighted ceiling. Measures shall be taken to limit the brightness of lamps installed on the sides of the site. This may be done with lamps with large light emitting surfaces or blinding lights. The vertical angle of the vertical plane parallel to the tennis court should be at least 30°. Increase to 45° if possible. The side lighting system can be supplemented by a lighting system on the ceiling, which provides an illumination of approximately 30[deg.] of the total horizontal illumination. This combination system can provide a good visual perception of the ball and the player, and is regularly and symmetrically installed throughout the playing field. When the competition needs to provide higher illumination, this arrangement is often necessary. These lamps do not have to be directly used in the use area. In addition, it is also necessary to limit the brightness of the light-shielding members used in these lamps.

(2) When the ceiling height is 10m or more, a well-controlled high-pressure discharge lamp with symmetrical or asymmetric light intensity distribution can be used. These light sources are also placed on or outside the field. Because of the high brightness of these lamps, special attention must be paid to masking.

(3) The light-emitting ceiling system using a straight tubular fluorescent lamp or a high-pressure discharge lamp may be composed of a diffused reflecting plate or a grid. To obtain a uniform ceiling brightness, the distance between the lamp and the ceiling must be sufficient. The required mesh size in the barrier should ensure comfortable viewing conditions. There should be a clear difference between the size of the grid and the diameter of the ball in order to prevent the grid from producing bullies. The shading angle of the grid is at least 30° in the long axis direction but may be smaller in the lateral direction.

The application of light sources can be summarized as follows:

(1) Fluorescent light is the most suitable light source for indoor tennis court lighting

(2) High-pressure gas discharge lamps can be used for indirect lighting systems and can be used as direct lighting in high pavilions where high illumination is required. In order to avoid the possibility of stroboflash effects caused by some discharge lamps, it is necessary to allow each part of the site to receive approximately equal illumination from at least two phase-powered lamps. Ballast operation of two lamps in the lead-lag mode will also reduce the flicker effect.

4. Auditorium

The stands should be located on the side of the tennis court, otherwise they may constitute a background for interference with the game. It is preferable to use the same type of light source throughout the seat and venue. The illuminance of the entire auditorium may be considered lower than the site itself, and an illuminance level of approximately 30° that approximates the average illuminance of the entire site may be considered as a suitable value.

5. Mechanical protection installation and maintenance

Lamps must be fitted with suitable mechanical protection devices. To prevent it from being damaged by the ball, a metal mesh or a shock-resistant plastic can be used for this purpose. The loss of light due to the use of these protective devices must be taken into consideration in lighting design.

In the initial stage of lighting design, maintenance of the lighting device must also be considered. Especially in high ceilings, it is necessary to take measures for easy access to lamps and lamp replacement during maintenance. Maintenance should be carried out regularly to avoid transitional light attenuation due to accumulation of dust and dirt. Similarly, lamps, lamps, and ballasts have lost their function or excessive light attenuation should be individually replaced to ensure that the illumination continues to meet regulations. The absolute minimum illuminance value shall be specified for the point illuminated by each device under its conditions.

Related reading: Tennis court lighting installation steps

Led Gaming Chair

Taihe Fangyuan Muye Co.,Ltd , https://www.fyofficefurniture.com