Research on the detection method of photoelectric color of LED lighting products

In recent years, with the continuous development of LED technology, high power semiconductor lighting device has been rapid development in recent years, especially white light power and light efficiency continues to improve, LED gradually entered the field of lighting, led to a new revolution in the field of lighting technology. LED after permutation and optical design in different ways, the formation of LED lighting products and LED lighting every kind of the product research and development in our country is like a raging fire, the performance level of LED lighting products has gradually improved. Under the premise of the correct test method, the accurate measurement of the photoelectric color parameters of LED lighting products is the basis of the scientific evaluation of the product performance, quality and development trend. In view of the current situation of photoelectric color detection of LED lighting products, combing with the accumulation of the LED products in the center, the author makes a summary and summary of the detection methods of the photoelectric properties of LED lighting products.

General evaluation of the performance indicators of LED lighting products

Classification of 1.LED lighting products

At present, LED lighting products can be divided into LED lighting (for example: LED road lamps, LED lighting, LED lamps, LED embedded tunnel lighting, LED decorative lamp, LED lamp) and traditional lighting alternatives (such as: LED lamps self ballasted lamps, PAR lamps, LED MR16, LED straight tube T8/T12 fluorescent lamp etc.). The LED luminaire is a complete illumination device comprising a LED based light emitting element and a matched driver, a light distribution member, a fixing and protecting light emitting element, and a device connected to the branch circuit component. Lighting LED lamp can be divided into non integral LED lamp and integral LED lamp two [10].

Non integral LED lamp package includes LED array (module) or LED package (component) and standard lamp holder and other components of photometric, thermal, mechanical and electrical components. The LED lamp should be installed in a standard lamp holder and LED drive. The LED lamp cannot be connected directly to the branch circuit.

Integral LED lamp package contains LED array (module) or LED package (components), LED drive, standard lamp holder and other photometric, thermal, mechanical and electrical components of the overall combination. The LED lamp can be directly installed on a standard lamp holder, which can be directly connected with the branch circuit. The biggest difference between LED lamp and LED lighting is that the LED lamp needs to be installed in the standard lamp holder.

Differences between 2.LED lighting fixtures and traditional light sources

At present, there are many differences between LED lighting and traditional light sources. First of all, the life of the traditional light source lamp can be replaced by the replacement of the damaged light source, lamp control device to meet the requirements, so generally do not evaluate the traditional light source lamp life. LED lighting is a LED light source and the lamp shell integration, the current life of the LED lighting and LED light source itself life, LED drivers and lamps to provide LED environment and many other factors. The life of different LED lamps can only be determined by the evaluation of the relevant life characteristics.

Secondly, different from the traditional light source lamp, LED lighting is light and light using a plurality of LED light sources or module, there is a color difference between light LED lamps, the spatial distribution of need to use the color space uniformity evaluation to evaluate the LED light color, different color viewing angle evaluation LED lamps the difference.

Thirdly, the traditional light source can be used for photometric test alone. Due to the characteristics of LED lamps and integrated LED light source is very sensitive to temperature, not suitable for the LED light source from the lamp to separate the individual measurements and photometric measurements should be carried out to test the overall use of LED lamps photometric absolute method.

Fourth, the traditional lighting fixtures to evaluate the efficiency of lamps, and LED lamps to use energy efficiency or light efficiency evaluation.

General evaluation of performance index of 3.LED lighting products

The general evaluation of the performance indicators of lighting products mainly includes: optical properties, electrical properties, color characteristics, thermal characteristics, life characteristics, reliability, etc.. At present, the evaluation of the performance indicators of LED lighting products mainly include the following aspects:

(1) the optical properties mainly include the intensity distribution, the initial output energy efficiency (luminous efficiency), the luminous flux, and the light intensity;

(2) electrical characteristics include: lamp power, power factor;

(3) the color characteristics include: color temperature and color rendering index, chromaticity coordinates, color tolerances, main wavelength (monochromatic), color distribution uniformity and color spatial uniformity;

(4) thermal properties include thermal resistance and junction temperature;

(5) the life characteristics mainly include the switching frequency test, the life / accelerated life test, the lumen maintenance rate (the luminous flux maintenance rate) / the light intensity maintenance rate (the reflective cup type MR16 or PAR lamp);

(6) reliability test.

Two, LED lighting products photoelectric color performance testing method

Because of the current LED lighting products of the thermal characteristics, life characteristics and reliability of the relevant standards are being studied and drafted, so this paper focuses on the LED lighting products photoelectric color detection method. The following sub LED lighting lamps and LED lamps two series to discuss.

1.LED lighting products test environment and physical conditions

LED lighting products tend to have optical components, so to be stored in a relatively clean environment and testing, the product to clean the lens without fingerprints. The test environment can not have excessive vibration and impact, reduce air convection. Due to the performance parameters of LED lighting products are more sensitive to temperature