Brief analysis of LED spotlight technical requirements

LED技术的快速发展，光效的不断提升，LED射灯技术也在快速发展。目前的LED射灯几乎是以替代传统卤钨灯为主。相比传统灯具，LED射灯在节能及长寿命方面具有显著优势。随着LED射灯成本的降低，LED射灯的应用也逐步开始普及。本文将从LED射灯的技术要求，常见LED射灯的规格及类型， LED射灯结构，LED射灯选购常识，以及LED射灯发展方向这几个方面做简单介绍和思考。

1. Technical requirements for LED spotlights

At present, LED spotlights are mainly used to replace traditional halogen tungsten lamps. The relevant safety requirements are mostly based on traditional lighting requirements, and a set of safety certification standards have been formed based on the characteristics of LED lamps. At present, in terms of LED spotlight certification, the main international certifications are European CE and North American UL, and voluntary certification (CQC) can be carried out in China.

CE certification includes two aspects: LVD and EMC. LVD is implemented in accordance with the EN60968 standard (to be upgraded to IEC 62560); EMC is implemented in accordance with EN55015, EN61547, EN61000-3-2 and EN61000-3-3 standards. In addition, LED lights usually need to refer to IEC 62471 for photobiological safety testing. In North America, UL safety and FCC electromagnetic compatibility certification are usually required. UL implementation standards are UL1993, UL8750 and UL1310; FCC implementation standards are FCC PART15 Subpart B. In China, voluntary certification (CQC) is used for LED spotlights, and the implementation standards are GB24906-2010 (safety) and GB 17743-2007 (electromagnetic compatibility).

In addition, there are also many standards and regulations for the performance of LED spotlights. The United States has relevant requirements for ENERGY STAR; China has energy-saving certification requirements, and the implementation standard is CQC 3129-2010. These requirements all stipulate the color temperature, color rendering index, initial luminous flux, luminous efficacy, luminous flux maintenance rate, life, center light intensity, nominal power, power factor, product labeling, etc. of LED spotlights.

The lifespan of many electronic products is judged by whether they break down, but LED is a light source with a very long lifespan and can be used for a long time without breaking down. However, the output of luminous flux will decay over time, so the industry usually defines the lifespan of LED light sources by the time it takes for the light to decay to 70%, i.e. L70. With the advancement of technology, the light decay of LEDs is getting slower and slower, and it is difficult to fully test the time it takes for the light to decay to 70%. Since the lifespan of electronic products follows an exponential law, LEDs are usually aged for a shorter period of time. By sampling the light decay data, the exponential function is used to calculate the time it takes for the light to decay to 70%. The calculation formula is as follows:

Usually, the luminous flux maintenance rate LM (Lumen Maintains) of the LED is tested for 6000 hours of aging. According to the exponential law, if LM>91.8% after 6000 hours, a lifespan of 25,000 hours can be claimed. If LM>94.1%, a lifespan of 35,000 hours can be claimed. However, the estimated lifespan time shall not exceed 6 times the test time.