DEVELOPMENT OF A NEW HIGH-POWER LED TRANSFER STANDARD

摘要

For the calibration or adjustment of measurement equipments it is always desirable to use transfer standards having similar properties compared to the device under test. In case of light sources, the best match is achieved when a transfer standard relies on the same technology as the light sources under evaluation. Thus, PTB has developed already in 2002 LED Transfer Standards with a heating resistor for fast temperature stabilisation and with standardised body housing. The typical total luminous flux of these LEDs is in the range of 1 lm. Due to the occurrence and rapid development of high-power LEDs - which can be used for lighting applications - there is a strong demand for traceable measurements of photometric properties of this LED type. Consequently, PTB developed a new transfer standard with compact dimensions, using commercially available high-power LEDs with luminous flux values up to 100 lm. These LED standards can be used to transfer photometric, spectroradiometric and colorimetric units from National Metrology Institutes (NMIs) to the user. The characterisation of this standard in terms of reproducibility and optical properties is described in this article.