LED luminous efficiency, LED thermal resistance, LED lights decline you know how much?
LED lights fades, heat runs through from the chip manufacturing, packaging process, material selection, lighting development of the entire industrial chain, the current industry concept of light fades, the causes and how to solve also lack of understanding, there is no authoritative interpretation of the theory, the relevant national standards Difficult to introduce.
The following were from the LED luminous efficiency, LED thermal resistance, LED light decline in three areas for a brief explanation.
LED lights effect: the distinction between transient light effect and the meaning of steady-state light effect
The luminous flux (lm) emitted by the LED light source divided by the power consumed by the light source (W) is called the luminous efficiency of the LED in lm / W. LED transient light efficiency refers to the luminous efficiency of LED light source when it starts to work, also called the initial cold state light effect.
Transient luminous efficacy is the short-time light-to-electricity conversion characteristic of LED light source, which is related to the quantum excitation capability of the chip and the phosphor, the refractive index of the colloid, the light transmittance, the reflectance of the support structure (reflector) and the like, Basically irrelevant. It only measures the contrast, the transient light efficiency does not represent the actual working condition.
Steady-state light efficiency refers to the LED light source to work for a period of time into the thermal stability, the steady-state light efficiency, including LED transient light and electrical properties, including the system heat transfer, thermal changes in temperature, also known as system light, is the whole Lamps real work efficiency.