General Electric Lighting Co., Ltd. Shanghai 201203
Abstract: This paper mainly analyzes the specific conditions of lighting applications. In the optical design of lamps, CIE fully considers the concept and requirements of green lighting. First, choose short arc, high light flux or high color rendering and high lumen maintenance rate. The modular design is used to combine the reflectors and hoods of different reflection functions to control the projection direction and beam shape of the light, improve the optical performance of the light control materials of the lighting fixtures, improve the light output efficiency of the lamps, and reduce the light leakage and deviation of the lamps. Shooting light, reducing the stray light generated by artificial lighting, improving the lighting level and visual comfort of lighting, controlling light pollution, saving energy and reducing lighting costs.
Keywords: optics design; luminaire; green lighting; spill light;
I. Introduction
As a unit of lighting unit, the luminaire can be divided into mechanical structure and installation system, electrical and lighting control system and optical lighting system. These three interact, interdependent and blend together to form a complete luminaire. The luminaire optical illumination system is a terminal execution component for realizing the luminaire illumination function. The system mainly includes a light source and a light control system, and its work ultimately reflects the performance of the luminaire. “Green Lighting†is a requirement for lighting. Its scientific definition is: through scientific lighting design, using high-efficiency, long-life, safe and stable lighting electrical products (electric light source, lamp electrical accessories, lamps, Wiring equipment and dimming and light control devices improve the conditions and quality of people's work, study and life, thus creating an efficient, comfortable, safe, economical and beneficial environment that fully reflects the lighting of modern civilization. “Green Lighting†is a new policy proposed by the lighting industry in the early 1990s. Its starting point is to save energy and protect the environment. The purpose of implementing green lighting is to develop and promote high-efficiency lighting fixtures, save lighting power, and establish a high-quality, efficient, economical, comfortable, safe and beneficial environment. Green lighting not only requires energy saving, but also meets lighting quality and visual environmental conditions. To achieve energy savings under the requirements, it is not possible to rely solely on reducing lighting standards to achieve the above objectives, but to improve the energy-saving capacity of the entire lighting system, with fewer lighting fixtures and lower power consumption under the same lighting standards and lighting quality. to fulfill.
Second, the optical design of lamps based on the concept of green lighting
The energy saving of the lighting system is mainly carried out in two aspects: one is to develop and promote the application of high-efficiency and high-quality lighting fixtures; the second is to provide reasonable lighting control systems and engineering applications. Research on high-efficiency lighting fixtures is mainly based on the design of the optical system of the luminaire, reasonably selecting the luminaire light source, scientifically designing the shape of the luminaire optical system, and adopting a cost-effective reflective material and a refracting light-control material.
(1) Choice of light source
When the principle of illumination of the electric light source is different, the manufacturing process is different, and the materials are different, the luminous efficiency is different. The luminous flux emitted by the unit power is called luminous efficiency (hereinafter referred to as luminous efficiency), and more specifically, the luminous ability of the electric light source. To save energy, first of all, try to improve the luminous ability of the electric light source, so as to generate as much light as possible with as little electric energy as possible. The luminous efficacy of metal halide lamps is close to or even exceeds 1001m/W. Some experts predict that the luminous efficiency in 2010 will reach 1201m/W, which is the main light source for floodlighting, road lighting and tall factory lighting; high-pressure sodium lighting has reached 1501m/W, it is currently the most efficient lighting source, mostly used for road lighting and flood lighting.
In practical lighting applications, one-sided pursuit of high color rendering and high color temperature of the light source can cause great energy waste. In the floodlighting of some stadiums, high-power metal halide lamps of 1000-2000W are generally used. According to the color rendering index, they are usually divided into 65 (or 80) and 90; according to the corresponding color temperature, they are divided into 3700K (or 4000K), 5600K two. The latter is usually used in international color TV broadcasts, Olympic games, "World Cup" games and high-definition television broadcasts; the former is used in daily training, competitions, and color TV broadcasts. In different regions of the world, such as North America and Europe, the standards of implementation are also quite different, and current sports lighting standards have different requirements. Light sources with different color rendering indexes and color temperatures have significant differences in light flux, taking a 1000W metal halide lamp source as an example. The light output of a metal halide lamp with a color rendering index of 65 is 110000 Lm, while the light output of a metal halide lamp with a color rendering index of 90 is only 90,000 Lm. The former's luminous flux is about 20% higher than the latter, which means that the latter can save about 20% under the same illumination level and illumination uniformity requirements.
The existing metal halide lamp structure is divided into two types: single-ended metal halide lamp and double-ended metal halide lamp (Fig. 1). Each metal halide lamp can be divided into two types: long arc tube and short arc tube (Fig. 1). , used in different lamps. Comparing these product characteristics, it can be found that the short-arc double-ended metal halide lamp has the following features: allowing the design of the luminaire system to be more compact, and the precise optical system has higher efficiency, good beam control ability and minimum overflow light; The ignition position is within ±5° of the horizontal direction, which is helpful for the stability of the metal halide lamp; however, during operation, the package part of the lamp will be exposed to the air, so the temperature of the lamp must be controlled, and the color difference between the lamp and the lamp is difficult. control. Single-ended short-arc metal halide lamps also have their own advantages, especially in the control of glare, spillover light and precise light distribution: they can also precisely control light, provide more light distribution options, and good light spillover. And glare control, transparent tubular outer glass bulb, high luminous efficiency, etc.; if the position of the ignition point within ±5° in the horizontal direction is maintained, the inherent chromatic aberration of the metal halide lamp can be minimized, and the light is high during the initial and ignition life. Effect, the lamp life is longer than the double-ended metal halide lamp, and the color difference between the lamp and the lamp is easy to control. According to the characteristics of the metal halide lamp, when the lamp is in the horizontal and vertical state, it is ignited, and the lamp has the highest ignition efficiency. When the general luminaire is installed on the light pole or the horse road, the aiming angle of the luminaire and the horizontal direction will have an angle of about 25°~40°. At this time, the inclination coefficient of the luminaire is low, and the total light loss coefficient is reduced. With the use of efficiency, more lamps must be used to achieve this lighting effect. Use a Z-shaped light source.