Lighting has changed the way of life that people “work at sunrise and rest at sunset”, extending the space and time of human activities, and lighting has become an irreplaceable requirement in today’s modern lifestyle. Lighting is generally divided into two categories: natural lighting and artificial lighting. Natural lighting is limited by natural conditions, and a light source that is readily available, adjustable in brightness and darkness, and stable light cannot be obtained according to people’s requirements. For a certain atmosphere, artificial lighting methods are often required. Artificial lighting can ensure that people engage in stable production and life, and prolong people’s activity time.
Whether it is indoor or outdoor, the purpose of installing lighting system can be summarized into the following three aspects:
①Easy to perform visual operations;
② show the environment conspicuously;
③Promote safety and protection.
Which one should be prioritized in the design process depends on the specific application. In the design, it is necessary to fully consider these three aspects to make compromises, and strive to achieve the determined goals and avoid excessive energy consumption.
(1) Meet the requirements of human visual work
Vision assignments vary in difficulty, mainly because of the different sizes of key details and the different contrasts between details and background. Illuminating a visual object makes it easier for people to see its details, but the amount of light required for adequate visibility varies for each object. Furthermore, if the visual object is three-dimensional or chromatic, the direction and color rendering of the incident light become the main factors determining its visibility.
To systematically articulate lighting standards and achieve these standard values for good lighting requires careful analysis of critical vision tasks, how they perform in different lighting applications, and then a decision on the implementation of well-considered tasks. In fact, this is an impossible solution, so most national and international lighting organizations in the world today follow a more practical approach in formulating suggested rules, that is, to include previous visual work that has proven satisfactory illustrate.
(2) Create a good light environment
In addition to illuminating specific objects and/or work implementations that ensure pedestrian safety, lighting systems use different types of light to represent the post-twilight environment and shaded areas during the day. In addition, lighting systems are also used in places that require special attention during the day, such as many hardware stores that do not need to emphasize the environment. Flood lighting on the exterior of decorative buildings has the primary purpose of presenting the environment. When it comes to lighting in parks and gardens, nighttime landscapes are often more attractive than daytime ones. In the design process, the image and shadow of light provided by other means of urban outdoor lighting systems and indoor lighting installations should be perfectly considered, usually the environmental landscape is premised on safety and visual performance. In any case, standards for ambient lighting are more difficult to articulate with complete certainty than those for implementing vision tasks. Table 1 lists the lighting environment requirements for different lighting designs.
In the actual lighting design, these factors should be fully considered, and then a compromise should be made according to the requirements of the actual situation. According to different lighting occasions, the requirements for lighting design considerations are also different. Table 2 lists the different requirements for the factors considered for different lighting occasions.
For a variety of reasons, mainly due to environmental concerns and secondarily economic factors, consumers in most countries are paying great attention to reducing energy consumption. Lighting accounts for 15% to 25% of energy consumption, so there is no excuse for wasting energy, especially when any energy saving means cost saving, which confirms this view. One of the easiest and most obvious ways to reduce energy consumption is to lower the standard required by lighting laws to reduce the amount of light used. However, this approach will damage pedestrian safety, social security and reduce production efficiency, so it is very important to achieve sustainable development of lighting. In addition to considering the use of green energy lighting, in order to minimize energy consumption, the following points should be noted in the lighting design process:
①Select the one with the highest luminous efficiency from those light sources with the same size, shape, color and luminous flux;
②Select those lamps with high maintenance factor (IP5 or above can be used indoors, and IP6 or above can be used outdoors);
③Select lamps with a relatively high utilization factor in the lighting of the house;
④ In flood lighting, select lamps with beam angles that match the opening angle of the illuminated area;
⑤Select a lighting system that can limit the large illumination in the work area in indoor lighting;
⑥ Using electronic sensors, the lights can be automatically turned off when there is no one in the room;
⑦ Use the corresponding control system in the indoor lighting to make full use of the available sunlight as much as possible;
⑧ Choose a maintenance strategy (usually including batch replacement) that minimizes total energy consumption throughout the year.
The basic principles of lighting design are practical, economical, safe and beautiful. The following issues should be considered in the design:
① Through scientific design, to meet the requirements of safety standards as much as possible, for example, the scientific design of road lighting can reduce the probability of traffic accidents;
②Meeting the minimum illumination requirements of the specification is conducive to improving product quality, production efficiency, and physical and mental health;
③Meet the lighting requirements of architectural functions, such as color rendering, brightness, light color, shock resistance, average life, fog penetration, etc.;
④ Determine the specifications of high and low voltage electrical appliances and wire material specifications;
⑤ Determining a reasonable project cost standard is conducive to saving energy. Generally, it is necessary to compare the best of several schemes;
⑥ Architectural lighting is an integral part of urban art and architectural decoration, and should meet certain artistic appreciation requirements of people.
Lighting design should be based on visual requirements, operation nature and environmental conditions, so that the work area or space can obtain good visual effects, reasonable illuminance and color rendering, suitable brightness distribution and comfortable visual environment. When determining the lighting scheme, the special requirements of different types of buildings for lighting should be considered, the relationship between artificial lighting and natural lighting should be properly handled, and the construction funds should be reasonably used and technologies such as the use of energy-saving light sources and high-efficiency lamps should be used.
The lighting environment design can be carried out according to the following steps.
①Collect original data: equipment layout, working conditions, environmental conditions and lighting requirements of lighting occasions; architectural design drawings, reserved lamp positions, etc.
② Determine the way and type of lighting, and choose a reasonable illuminance or brightness.
③Select the light source to be used.
④Choose the form of the lamp and determine the model.
⑤ Arrange the distribution of lamps.
⑥ Calculate the illuminance to determine the power of the light source.
⑦ Calculate the brightness and glare evaluation of each indoor surface as needed.
In short, the purpose of lighting design is to provide a comfortable and bright environment and safety guarantee according to the requirements of human visual function. Lighting design can not only create a good light environment, enable people to engage in visual work comfortably and efficiently, thereby improving production efficiency, product quality, and reducing accident avoidance, but also uses the directionality and hierarchy of lighting to render buildings and use illuminators to enhance the atmosphere of the environment. , to create a beautiful light environment. Electric lighting design has become an integral part of modern architecture, and has an increasingly widespread impact on people’s production and life.
Whether day or night, people expect adequate lighting to meet the needs of activities. For example, in order to meet people’s safe entry and exit in the building, this requires the necessary lighting in the circulation area, especially in places such as terrain changes and dangerous equipment operations, must be equipped with sufficient lighting. In the event of failure of the main power supply system, emergency lighting should be provided in all workplaces and public access areas. There used to be a saying in road lighting that the street lighting system installed on the road allows drivers to drive safely without turning on the lights. However, since the lights have another function, which is to signal other drivers, drivers still need to use the lights even in good street lighting conditions.
Obviously, a good street lighting system can make the driver’s work easier, and a lot of facts prove that the installation or improvement of the street lighting system has the effect of reducing the occurrence of traffic accidents. As for those non-main roads and streets in residential areas, relatively simple lighting should be used, and its main function is to ensure the safety of pedestrians, and drivers should use the lights to drive slowly.
Urban lighting not only ensures the safety of pedestrians at night, but also provides security for social security. Studies have shown that a small amount of lighting can change the incidence of crime, and it is clear that lighting can play a role in deterring crime and preventing criminal attacks. Many factories have buildings that stay open all night for safety reasons.