LED on building landscape lighting

      At present, LED has become popular in the field of city night lighting in our country. Almost all city night lighting in the country are using LEDs. In particular, my country took the 2008 Beijing Olympics and 2010 Shanghai World Expo as an opportunity to promote the application of semiconductors in urban landscape lighting. , This will further promote the wider use of LEDs in the field of urban lighting in our country. However, we should see that quite a few cities do not understand the characteristics of LEDs in terms of night scene lighting. There are many misunderstandings in the design, construction, maintenance and management of night scene lighting, resulting in the poor use of LEDs in urban night scene lighting, and the evaluation is not high. In particular, some abuse of LEDs makes the city night scene beauty feel damaged and negatively affects some people. Doubts about the use of LEDs in urban night scene lighting have affected the reputation of LED in urban night lighting. If it is not solved in time, it will definitely affect the healthy development of my country's LED industry chain.

        1 Requirements for building landscape lighting

        Nightscape buildings are more of the constituent elements of cities, such as residential buildings, commerce, schools, hospitals, offices, sports, theaters, convention and exhibition buildings, and some industrial buildings. According to their forms, these buildings mainly include Chinese and Western traditional styles, and modern buildings with the characteristic style of Xiamen R ethnic group. Jingxian lighting should understand the architectural features of the subject under supervision.

        For architectural lighting, the "Code for Design of Urban Landscape Lighting" just released by the state requires:

        (1) Full consideration should be given to the direction of light projection, the position of the lamp, the viewing direction, the material of the illuminated object, etc., to achieve beautiful, safe and comfortable technical results.

        (2) The color light should be used scientifically and reasonably according to the color of the building surface. When operating the color light, it should be thick with the nature of the building, the surface color, and the surrounding environment.

        (3) Lighting facilities such as lamps and lanterns should be concealed. When concealment is not possible, the shape, scale and color of the lighting facilities should be in harmony with the environment.

        1.1 How to landscape lighting for buildings

        When lighting the night scene, one should understand the features, functions, styles, facing materials, surrounding environment and social calendar and cultural connotations of the illuminated objects, as well as the architect's creativity and design expression intentions, and the requirements of the owners. According to the characteristics of the illuminated object and the surrounding environment, the night scene lighting should be organically combined to highlight the key points and take into account the overall image. At the same time, the night scene lighting facilities should not damage the visual image of the city during the day. Colored light has a strong emotional color, so be careful to use colored light in night lighting. The principle of using colored light is: colored light is coordinated with the function of the building (structure); colored light is coordinated with the color of the building (structure) finishing material; the colored light is coordinated with the hue and characteristics of the surrounding environment. The illumination direction should avoid people's sight to prevent glare; night scene lighting should control the light to the sky and to the residential windows to reduce the degree of light pollution. The brightness and color should be determined reasonably according to the use function, architectural style, structural characteristics, surface material texture and the effect in the night scene lighting of the illuminated object. The use function, architectural style, structural characteristics, architectural features, cultural connotation, surface material color and light reflection of the building (structure) should be analyzed to determine the appropriate lighting method.

1.2 How should architects consider architectural design

        In order to enrich the image of the building at night, it is recommended that the following factors should be considered in the design of the facade of the building, especially the high-rise building:

        (1) The facade should be treated with some bumps and lines as much as possible, and try to avoid the whole flat gable. The gable is treated with some shapes that can avoid the installation of lamps. In particular, some components that can be installed in the middle and upper part of the gable can be used in sections. The lighting distance reaches the middle and upper part.

        (2) If the outer edge of the wall is the place where the facade lighting is often handled, some horizontal concave-convex decorative lines should also be considered to make the lights have a place for installation.

        (3) The front facade (the facade other than the gable) is the focus of lighting treatment, with large windows. If it is a residence, it is generally prohibited to use high-power floodlights to avoid light pollution to the residence, but if there is no light, the image of the building at night will be affected.

        Therefore, when designing the building, it should be considered that the light can be installed to illuminate the building without the light entering the window. It is recommended to deal with some vertical grooves in the design of the facade structure. If it is a residence, you can leave a little more solid wall surface or decorative lines on the concave surface of the kitchen and bathroom for lighting treatment.

        (4) The front or side facade balconies of the residence, the canopy of the windows and its outer edges should also consider the places where low-power lights or contour lights may be installed.

        (5) The treatment of the top of the building is the focus of the architectural landscape lighting, and it is also a very important light carrier for the urban landscape. Generally, it does not constitute a negative impact on households or people. The light used in the lighting treatment is more emphasized, and the brightness is generally high. The shape of the building should be richer, and at the same time, try to consider hiding the lamps and lanterns so that they are not exposed.

        (6) The glass curtain wall is another difficulty in landscape lighting. It is forbidden to use the floodlights, and the internal light transmission treatment should be adopted. Developed countries generally do not turn off the lights at night for the entire building, which naturally means internal light transmission. However, our country’s economic development level and energy supply cannot fully meet the internal light transmission requirements. According to our country’s actual economic conditions and to make the building beautiful at night , ~ It is generally used to install lights inside the glass curtain wall or window, or to decorate some point and line light sources outside the window. Therefore, the actual situation should be taken into consideration when designing the building facade structure, and the place where the point-like linear light source is installed can be appropriately considered.

        (7) Attention should be paid to remind electrical professionals to consider the power load of landscape lighting on the building, and reserve the problem of light-transmitting power or line laying for glass curtain walls or multi-window buildings in public buildings.

        2 LED's problems in building landscape lighting

        2.1 Blind worship period-distrust period and neutral awareness period

        When LEDs are used in landscape lighting, the widely promoted advantages of higher education, energy saving and long life, are enthusiastically accepted by a mysterious eye in society, and they are widely used in landscape lighting. Due to the many technical links brought by a series of very complicated processes such as chip material packaging and scraping devices, lamps and lanterns, and landscape lighting, the quality is affected. These important technical links are ignored by the media and commercial sales promotion. When the society believes that LEDs can solve all the problems of landscape lighting and the quality problems that occur in real projects have not been realized, the gap in high expectations for LEDs has seriously affected the sense of trust in LEDs. In the previous period, the amount of landscape lighting was greatly reduced. With the continuous improvement of LED quality. LED has many advantages that other light sources do not have, such as energy saving, environmental protection, long life, rich colors, fast shoulder movement, flexible combination changes, etc. HJong can be used properly to fully display the beauty in landscape lighting. At present, people's confidence in LED is gradually strengthening. We call it the neutral period of cognition, where trust and doubt coexist. This is a warning to the LED industry. Only by improving and consolidating the high quality of LED lighting products, will it continue to expand the influence of LED in the application of landscape lighting, and maintain the society's trust in LED landscape lighting.

        2.2 The quality of LED products for landscape lighting is uneven

        The uneven quality of landscape lighting products is still an important factor that will cause flaws in the LED industry for a long time. Some units spend a huge amount of money to use LEDs for landscape lighting. Some problems occur within ten and a half days. Insufficient contours are caused by abnormal color changes or other problems. This makes it a burden to find the construction unit for maintenance.

        2.3 Improper use of LED design methods in landscape lighting

        This is a common problem that has existed for a long time. The application of LEDs in urban night scene lighting has become more common (especially in some large cities). Because some night scene designers do not really understand the performance of LEDs, they do not use large amounts of LEDs in the night scene lighting design according to the illuminated object, the characteristics of the attached carrier, the function and the specific environment, resulting in some cities only relying on LEDs for night scene lighting. The night scene shaping method is single, the night scene image is monotonous, and it does not achieve the beauty of the city night scene; some use the matrix method on the glass curtain wall of the government administrative office building to change various patterns, follow the light and flash the shape of the dynamic and gorgeous colors , Is considered to be a place of entertainment; some in hospital buildings and surrounding environments, office buildings, residential buildings and communities use LED linear and spot lights to follow the flashing, colorful changes are dazzling; some are on the gables and tops of important buildings Use LEDs to attach some component shapes to form patterns, destroying the architectural style during the day and changing the architectural form at night; there are also some LEDs with light color changes everywhere in the school area and quiet overflow area, which are strange and cause serious color and light pollution; some are in The use of many high-brightness LEDs in an environment with very low background brightness causes glare with too much contrast; some use LEDs with color changes near the traffic signal lights, causing the illusion of traffic signals for drivers and pedestrians, and so on. These incorrect designs give the general public a misjudgment that the LED itself is wrong, which makes some cities lose confidence in the use of LEDs for night scenes, and affects the development of LEDs in the field of urban night scene lighting.

        3 Application method of LED in building landscape lighting

        The correct use of LED landscape lighting in buildings is an issue that we must pay attention to. LED underground lights, underwater lights, emergency lighting, courtyard lights, various sign lights, LED local flood lights, LED line light sources, LED point light sources, etc., have greatly enhanced the urban landscape lighting. effect. Especially the LED has good color, relatively low energy consumption, relatively long life, low voltage, safe use, no pollution, good impact resistance and shock resistance, small size and convenient concealment, suitable for night scene lighting principles where the light is not visible, etc., these are all night scenes The use of lighting provides optionality. However, the night scene lighting must be selected according to the characteristics of the LED itself. In terms of design, some building gables, architectural items and other places that require a large area of light projection or display their structural shapes, should be carefully selected LEDs, and compare whether LEDs have the advantages of floodlighting. LEDs should be used with caution in places where wide beam angles and long transmission distances are required for illumination. It is necessary to consider whether the current LED lamps can meet this requirement? LEDs are suitable for contours, small transmitted light from point light sources, or matrix combination in glass curtain walls to form patterns, commercial places, places or carriers that require dynamic changes and rich colors. If some building night scenes are suitable for other light sources and LEDs to cooperate with each other, it can bring out the advantages of LEDs. For example, some buildings need to be flooded, but generally the lamp body is too large to affect the daytime landscape of the building. At this time, LED floodlights can be used, which are small in size and easy to conceal. This is an advantage that other light source floodlights do not have. At present, there are also some high-power LED floodlights, but due to the radiator, the lamps are too heavy and not suitable for floodlighting outside the building.

        These factors should be considered in the management and design of urban landscape lighting. When reviewing the night view design plan, the design review is strictly controlled, and it is best not to use the night view plan that cannot fully utilize the strengths of the LED during the design. In the implementation, the quality of LEDs for night scene purchases is strictly controlled, and the purchase of LED products is strictly controlled. A strict engineering supervision system shall be implemented during the construction process. Anything that does not meet the construction and installation specifications and requirements must be corrected, and non-standard construction and installation behaviors shall be eliminated. After the completion of construction, the acceptance system shall be strictly implemented, and the acceptance shall be carried out in accordance with the normative standards. The operation and maintenance system should be established in the LED night scene project that is put into use, with corresponding maintenance personnel, and the operation and maintenance and inspection records should be made. Once problems are found, they should be repaired and discharged in time, so that the landscape lighting projects using LEDs always remain normal. The operating status of LEDs keeps the credibility of LEDs in landscape lighting.

        4 Conclusion

        LED is used for urban landscape lighting, especially for the scene lighting of urban buildings (structures), showing its strong advantages. LED has the advantages of energy saving, safety, environmental protection, rich color, long life, small size, short response time, etc., which is very suitable for urban architectural scene lighting. As long as we use LED to strengthen the correct guidance for urban landscape lighting. Adopting correct design methods, with the continuous improvement of various performances of LEDs, the decline in prices, and the further in-depth application of LEDs, especially the successful application of LED landscape lighting for the Beijing Olympic venues and the Shanghai World Expo, for our LED landscape lighting A demonstration role. We believe that the use of LEDs in urban landscape lighting will be more widely promoted in our country, and LED manufacturers in our country should be fully mentally prepared.