The candela is the SI base unit of luminous intensity. Since the 16th General Conference on Weights and Measures in 1979, the candela is defined from the watt. This enables to materialize it with a photometer, as long as this photometer is traceable to a radiometric reference.A new "candela" has been recently developed at the LNE-INM, the French national metrological institute. That candela is based on 5 photometers made of 3 elements : a detector, a filter and an aperture. The detector is a "homemade" trap detector. Five filters have been calculated, realised and tested. They are mounted in a dedicated holder with a Peltier element that allows a temperature regulation. The surface of the aperture has been measured using a contactless method, based on a microscope and a micrometric XY motion table.We present here the different elements of our photometers. We briefly expose the uncertainty budget. The new French candela, developed at the LNE-INM, is currently operational. The standard uncertainty (1σ) associated to the luminous responsivity of our photometers is 1,9 10-3.
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