Analysis of technical indicators of LED tunnel lighting engineering

Foreword: Energy-saving research on new light sources for tunnel applications has attracted industry attention, and energy-saving research on LED tunnel lights has made significant progress. Because LED is used in tunnel lighting according to the scientific research results of Ming Vision and intermediate vision theory, color rendering and illumination, LED lighting tunnels have been used in many important tunnel lighting projects in China. The application of LED tunnel luminaires in tunnel lighting projects has made breakthroughs, but there are still problems. For example, there are no specific design and construction specifications for tunnel luminaires with LED as the light source, and product performance is uneven.

This article will analyze the key technical indicators that need to be paid attention to in the LED tunnel lighting project, and hope to provide reference for the design unit and users.

Optical part LED light effect

The LED single-watt lumen output is the basic indicator for determining whether the LED tunnel light has practical value. According to the requirements of the actual use of the LED tunnel light, the single-watt lumen of the LED used for the LED tunnel light should reach 90 lumens. After the rapid development of LED luminous efficiency in 2006 and 2007, CREE, Lumileds, and Hong Kong Zhen Mingli and other famous brands have successively launched the latest LED models.

Secondary light distribution distribution pattern

At present, the common distribution patterns of light distribution include concentrating light distribution, side emission type light distribution, and Lambertian light distribution. Different application modes are applicable to different light distribution forms. For example, road lighting should use batwing type light distribution, and spot light should adopt concentrating type light distribution. Due to the particularity of tunnel lighting, the arrangement density of lamps in tunnel lighting is very high, so the secondary light distribution form of the lamps in tunnel lighting is different from general road lighting. In the tunnel illumination, the batwing type light distribution and the Lambertian type light distribution can meet the illumination uniformity requirement. This is mainly because the lamp distance in the tunnel illumination is relatively small. For example, the middle section of the domestic tunnel lighting project has only 5 Meter.

The Hong Kong Zhen Mingli 75 tunnel light uses the commonly used batwing light distribution in road lighting and tunnel lighting, while the domestic LED tunnel light is Lambertian light distribution.

Particularity of light distribution design

Although the requirements for the distribution pattern of light distribution in tunnel illumination are relatively loose, it is necessary to have a light distribution design. Since the light distribution design is based on the primary light distribution of the light source, different light source types have different distributions, and the corresponding light distribution design also changes. Therefore, although there are professional manufacturers of reflectors, lenses and manufacturers, the products they provide are only based on a certain kind of LED light source. Of course, they can only be suitable for a certain kind of LED light source. Moreover, the types of LED light sources are rapidly increasing. In addition to the replacement of LEDs, the reflectors and lenses must be updated. Therefore, the secondary light distribution design must be completed by the tunnel light manufacturer itself. However, there are not many manufacturers that can independently carry out light distribution design.

Choice of light distribution

Commonly used face types are: spherical, ellipsoidal, hyperbolic, parabolic, and free-form surfaces, among which free-form surfaces are the most widely used and the most widely used. In addition, planes are also used in light distribution, but the plane usually only plays a transitional role—expanding the light source, but not the true light distribution. For example, the light distribution of an LED tunnel light in China is to select the plane as the light distribution surface type, so the final light distribution is actually the light distribution of the LED. There is no strict secondary distribution in this LED tunnel light. Light.

Predicting the lighting effect

In order to predict the lighting effect and installation method of the luminaire in the tunnel lighting, it is usually necessary to simulate in the special lighting software according to the basic parameters of the construction site and the photoelectric test data of the luminaire (for example, the file in IES format). Analyze, evaluate the lighting effects of the fixtures, and determine the best parameters for the installation.

If the results of the simulation analysis are not satisfactory, then it is necessary to modify the light distribution design or adjust the power of the lamps. At present, Hong Kong Zhen Mingli has the ability to complete the entire process from light distribution design, optical grade mold making, photoelectric test analysis to engineering effect design and analysis.