LEDs in architectural landscape lighting

introduction

At present, LED has begun to be popularized in the field of urban night scene lighting in my country. Almost all urban night scene lighting in the country widely uses LED. In particular, my country has taken the 2008 Beijing Olympics and the 2010 Shanghai World Expo as opportunities to promote the application of semiconductors in urban landscape lighting, which will surely further promote the wider use of LED in the field of urban lighting in my country. However, we should see that quite a few cities do not understand the characteristics of LED in night scene lighting. There are many misunderstandings in the design, construction and maintenance management of night scene lighting, resulting in poor results and low evaluation of the use of LED in urban night scene lighting. In particular, there are some abuses of LED, which have destroyed the beauty of urban night scene and caused negative effects, causing some people to doubt the use of LED in urban night scene lighting, affecting the reputation of LED in urban night scene lighting. If it is not solved in time, it will inevitably affect the healthy development of my country's LED industry chain.

1 Requirements for building landscape lighting

Chongqing night scene buildings are the most common elements in the city, such as residential, commercial, school, hospital, office, sports, theater, exhibition building and some industrial buildings. These buildings mainly include traditional Chinese and Western styles, modern style and Xiamen ethnic style buildings. Scene lighting should understand the architectural characteristics of the monitored objects.

For architectural lighting, the "Urban Landscape Lighting Design Specifications" recently issued by the state require:

(1) The direction of light projection, lighting position, viewing direction, and the material of the illuminated object should be fully considered to achieve a beautiful, safe, and comfortable effect.

(2) Colored light should be used scientifically and reasonably according to the color of the building's surface. When using colored light, attention should be paid to its compatibility with the building's nature, surface color, and surrounding environment.

(3) Lighting facilities such as lamps should be concealed. If concealment is not possible, the shape, size and color of the lighting facilities should be coordinated with the environment.

1.1 How to landscape lighting buildings

When carrying out night scene lighting, we should understand the characteristics, functions, styles, finishing materials, surrounding environment and social and historical cultural connotations of the illuminated object, as well as the architect's creativity and design expression intentions, owner requirements, etc. Night scene lighting should organically combine multiple lighting methods according to the characteristics of the illuminated object and the surrounding environment, highlight the key points, take into account the overall image, and at the same time, the night scene lighting facilities should not destroy the visual image of the city during the day. Colored light has a strong emotional color, and colored light should be used with caution in night scene 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 materials; colored light is coordinated with the hue and characteristics of the surrounding environment. The direction of lighting should avoid people's sight to prevent glare; night scene lighting should control the light directed to the sky and the windows of the house to reduce the degree of light pollution. The brightness and color should be reasonably determined according to the use function, architectural style, structural characteristics, surface material texture and its effect in night scene lighting of the illuminated object. The building's function, architectural style, structural characteristics, architectural features, cultural connotations, surface material color and light reflection should be analyzed to determine the appropriate lighting method.

1.2 How should architects consider architectural design?

In order to enrich the image of buildings at night, it is recommended that the following factors should be considered when designing the facade structure of buildings, especially high-rise buildings:

(1) The facade should have some concave and convex parts, lines, etc., and try to avoid having a flat gable. The gable should be designed with some shapes that can hide the installation of lamps. In particular, some components that can be installed with lamps should be installed in the middle and upper part of the gable, and the lighting can be divided into sections so that the lighting distance reaches the middle and upper part.

(2) If the outer edge of the wall is where the facade lighting is often processed, some horizontal concave and convex decorative lines should also be considered to provide a place for the lamps to be installed (it is best to hide the lamps).

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

Therefore, when designing a building, it is necessary to consider the position where the lights can be installed to illuminate the building, but not to allow the light to enter the window. It is recommended to deal with some vertical grooves in the facade structure design. If it is a residential building, the concave surface where the kitchen and bathroom are set up can leave a little more solid wall or decorative lines for lighting treatment.

(4) The balcony on the front or side facade of the house, the awning of the window and its outer edge should also be considered as places where low-power lights or outline lights may be installed.

(5) The treatment of the top of the building is the focus of architectural landscape lighting and is also a very important light carrier for the urban landscape. Generally, it does not cause a negative impact on residents or people. The use of light is emphasized in the lighting treatment, and the brightness is generally high. The shape should be richer when designing the building, and at the same time, try to hide the lamps and not expose them.

(6) Glass curtain walls are another difficulty in landscape lighting. They prohibit the use of floodlights and should be treated with internal light transmission. Developed countries generally do not turn off the lights in the entire building at night, so they are naturally internally lighted. However, my country's economic development level and energy supply cannot fully meet the requirements of internal light transmission. According to my country's actual economic situation and to make the building beautiful at night, it is generally adopted to install lights inside the glass curtain wall or window, or to make some point or line light source decoration outside the window. Therefore, this actual situation should be taken into account when designing the building facade structure, and appropriate consideration can be given to the installation of point or line light sources.

(7) Please remind electrical professionals to consider the electricity load of landscape lighting on buildings, and reserve electricity or wiring for internal light transmission in buildings with glass curtain walls or multiple windows in public buildings.

2 Problems with LED in Building Landscape Lighting

2.1 Blind worship period - distrust period - neutral recognition period

When LED is used for landscape lighting, the widely publicized advantages such as high energy saving and long life are warmly accepted by the society with a mysterious eye, and it is widely used in landscape lighting. Due to the many technical links brought about by a series of very complex processes from chip material packaging to device lamp production, as well as landscape lighting, the quality is affected. These important technical links are ignored by the media and commercial sales propaganda. When the society believes that LED can solve all the problems of landscape lighting, but the quality problems in the actual project cannot be realized, the gap in high expectations of LED has seriously affected the trust in LED. The use of landscape lighting has been greatly reduced in the previous period. 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 operation, flexible and diverse combination changes, etc. If used properly, it can fully show the beauty in landscape lighting. At present, people's confidence in LED is gradually increasing. We call it the neutral recognition period, that is, trust and suspicion coexist. This is a warning to the LED industry. Only by improving and consolidating the high quality of LED lighting products can we continue to expand the influence of LED in landscape lighting applications and maintain society's trust in LED landscape lighting.

2.2 The quality of LED products for landscape lighting varies

The uneven quality of landscape lighting products will continue to be an important factor that will cause damage to the LED industry for a long time. Some companies spend a huge amount of money to use LED for landscape lighting, but problems arise within ten days or half a month, such as insufficient outlines, broken lines, abnormal color changes or other problems, which often require the company to find a construction company for repairs, which becomes a burden.

2.3 Improper design methods for landscape lighting using LEDs

This is a common problem that has existed for a long time. The application of LED in urban night scene lighting has become common (especially in some large cities). Because some night scene designers do not really understand the performance of LED, they use a large number of LEDs in night scene lighting design without considering the illuminated object, the characteristics of the attached carrier, the function and the specific environment. As a result, some cities rely solely on LED for night scene lighting, resulting in a single method of shaping the night scene, a monotonous night scene image, and the beauty that the urban night scene should have; some use a matrix full-cover method on the glass curtain wall of the government administrative office building, changing various patterns, chasing the dynamic shape and bright colors of the flashing light, which is considered to be an entertainment venue; some are in hospital buildings and surrounding environments, office buildings, residential buildings and communities. LED linear and dot lights are used to chase and flash, with colorful and varied changes that dazzle the eyes; some LEDs are used on the gables and tops of important buildings to add some components to form patterns, which destroys the architectural style during the day and changes the architectural form at night; some LEDs with light color changes are set up everywhere in school districts and quiet areas, which are bizarre and cause serious color light pollution; some use many high-brightness LEDs in an environment with very low background brightness, causing glare with too much contrast; some use LEDs with color changes near traffic lights, causing drivers and pedestrians to have traffic signal illusions, etc. These incorrect designs give the general public a misjudgment that the LED itself is wrong, causing some cities to lose confidence in the use of LEDs for night scenes, affecting the development of LEDs in the field of urban night scene lighting.

3 Application methods 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 buried lights, underwater lights, emergency lighting, garden lights, various sign lights, LED local floodlights, LED line light sources, LED point light sources, etc., have played a great role in adding luster to urban landscape lighting. In particular, LED has good color, relatively low energy consumption, relatively long life, low voltage, safe use, no pollution, good impact and shock resistance, small size and easy concealment, suitable for the principle of night scene lighting that sees light but not lights, etc., all of which provide optionality for night scene lighting. However, night scene lighting must be selected according to the characteristics of LED itself. In design, some building gables, building tops, etc., where a large area of ​​light is required or where its structural form is displayed, LED should be carefully selected, and it is necessary to compare whether LED has the advantage of floodlighting. LED should also be used with caution in places where a wider beam angle and a long transmission distance are required for lighting. It is necessary to consider whether the current LED lamps can meet this requirement? LED is suitable for outlines, transmitted light with small point light sources, or matrix combinations in glass curtain walls to form patterns, commercial places, places or carriers that require dynamic changes and rich colors. For example, some buildings at night are suitable for other light sources to be used in conjunction with LEDs, which can better highlight the advantages of LEDs. For example, some buildings need to be partially floodlit, but the lamp is generally too large and will affect the building's daytime landscape. At this time, LED floodlights can be used. They are small in size and easy to hide, which 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 are not suitable for floodlighting on the exterior of buildings.

These factors should be taken into account when managing and designing urban landscape lighting. When reviewing the night view design plan, we should strictly control the design review. It is best not to adopt the night view plan that cannot fully utilize the advantages of LED during design. In implementation, we should strictly control the quality of the purchased LED for night view and strictly control the purchase of LED products. A strict engineering supervision system should be implemented during the construction process. Anything that does not meet the construction and installation specifications and requirements must be corrected to eliminate irregular construction and installation behaviors. After the construction is completed, the acceptance system should be strictly implemented and acceptance should be carried out in accordance with the specifications and standards. The LED night view project put into use should establish an operation and maintenance system, be equipped with corresponding maintenance personnel, and keep operation and maintenance and routine inspection records. Once a problem is found, it should be repaired and eliminated in time, so that the landscape lighting project using LED can always maintain a normal operating state and maintain the reputation of LED in landscape lighting.

4 Conclusion

Chongqing Grand Theater LED Solution

LED is used in urban landscape lighting, especially in the landscape lighting of urban buildings (structures). It has shown its powerful advantages. LED has the advantages of energy saving, safety, environmental protection, rich colors, long life, small size, short response time, etc., which is very suitable for urban building landscape lighting. As long as we strengthen the correct guidance of the use of LED in urban landscape lighting. Adopt the correct design method, with the continuous improvement of various performances of LED, the decline in prices, and the further in-depth application research of LED, especially the successful application of landscape lighting of Beijing Olympic venues and Shanghai World Expo LED landscape lighting, it has played a demonstration role for our LED landscape lighting. We believe that the use of LED in urban landscape lighting will be more widely promoted in my country, and my country's LED manufacturers should be fully prepared.