I. Overview of LED Stadium Lighting
The lighting design of the stadium focuses on the lighting of the venue, which is the competition lighting. The lighting in the venue is a functional, technical and difficult design. To meet the requirements of various sports competitions, it is conducive to the athletes' technical level, which is conducive to the correct judgment of the referees, and is conducive to the viewing effect of all parties in the audience. In addition to meeting the requirements of sports competitions, stadiums with multi-functional requirements should also meet the requirements for concerts, entertainment performances, and gatherings.
The design of the stadium should pay special attention to the live broadcast of the color TV. In order to ensure vivid and clear images and vivid colors, there are specific requirements for vertical illumination, illumination uniformity and stereoscopic effect, color temperature and color rendering of the light source. The lighting design of the stadium includes two aspects, namely, it can meet the requirements of illumination standards and lighting quality, and is also one of the main signs for evaluating a stadium.
Second, the illumination requirements of stadium lighting
The lighting standards of the stadium are related to the competitions held and whether there is any color TV broadcast. At present, the "Architectural Lighting Design Standards" GB50034-2013 has regulations, but it is not specific.
Third, quality requirements of stadium lighting
For the lighting quality requirements of stadium sports venues, there must be a higher brightness and color contrast on the entire sports field. There should be enough light at each point, the illumination should be uniform, the stereoscopic effect should be strong, and there should be a suitable light distribution. In the venue lighting required for color TV broadcasting, the color temperature and color rendering of the light source should meet the requirements of color TV broadcasting and limit the glare.
Glare limitation is the visual response that light falls on the retina and causes discomfort or reduced vision when viewing objects. It also has different effects on different people. Glare depends on three factors: distance, brightness and direction. Under normal circumstances, people do not directly aim at the light source. In order to ensure the uniformity of illumination and avoid glare interference, the elevation angle of the indoor sports field to the elevation of the luminaire must be greater than 45°, and because the indoor lighting equipment is far away from the athletes and the audience, the lighting is required to have precise control. Indoor glare may also be caused by smooth floor or reflected light from the water surface, so carefully consider the lighting equipment configuration to meet the lighting needs in various situations. In addition, the addition of grilles and baffles to the luminaires can also help control glare.
2. illuminance uniformity, three-dimensional
Illumination uniformity refers to the ratio of the minimum illuminance to the maximum illuminance in the illumination area, or the ratio of the minimum illuminance to the average illuminance. The larger the value, the more uniform the illumination.
Stereoscopic is the effect of lighting on objects (ie athletes and sports equipment), making their shapes look sharp and detailed. "Sports Hall Lighting Design and Testing Standards" JGJ153 stipulates that the average illuminance of the main stage of the TV broadcast should be 0.75~2.0 times of the average vertical illuminance. FIFA and IAAF stipulate that the ratio is 0.5~2.0, Beijing Olympic Games, The Athens Olympics stipulates that the ratio is 0.75~1.5. In the stadium sports venue lighting, the illuminance at the corners of the general site and the four corners is relatively low. Increasing the illumination at the edge and the four corners, and properly controlling the highest illuminance value in the central area of the site is beneficial to ensure uniformity. Lateral lighting and luminaire modeling should pay attention to how to improve the vertical illuminance value and properly control the horizontal illuminance value, which is beneficial to ensure the stereoscopic effect.
3. source chromaticity parameters
In lighting facilities, the resulting lighting effects are different due to the different light colors of the light source used. Therefore, when designing, it is necessary to study the characteristics of the light source from the quality other than the illuminance. On the other hand, when the color rendering index of the light source is different, the formed light atmosphere is different, and it is necessary to adopt an appropriate light source according to the motion content. For the LED light source, the special color rendering index R9 is also an important technical indicator. Generally speaking, when there is a TV broadcast, R9 should not be lower than 0; when there is a high-definition TV broadcast, R9 is preferably not lower than 20.
4. color TV broadcast quality requirements for lighting
Color TV broadcast lighting is the main indicator of the design of the vertical illumination of the venue. Sports venue lighting generally must meet the requirements of athletes, spectators and videographers. To this end, the horizontal illumination, the vertical illumination, and the brightness of the camera when shooting the panoramic picture must be kept consistent. The ratio of brightness change between the athlete, the venue and the audience must not exceed a certain value, so as to adapt to color TV, HDTV, or even Ultra high definition TV broadcast camera requirements.