Extended Wavelength Led for Radiometrical and Photometrical Calibration

Abstract

Typical white LED has limited energy beyond the band of (420-720) nm, which is not suitable as a transferring standard for spectral radiant flux, spectral irradiance. An extended wavelength LED has enough spectral intensity in the whole visible range has been developed, by six LED dies and RGB phosphor. The spectrum and stability of the developed LED was evaluated and the possibility of it to be used as luminous flux lamp was studied in a 2m integrating sphere-spectroradiometer, the testing result shows it could be worked as a reference standard for transferring spectral radiant flux to calibrate the luminous flux for generally used LED inside the range of uncertainty.

Establishment of 2π total spectral radiant flux scale with a broadband LED-based transfer standard source

“…Some reports have described the development of new LED sources as a transfer standard or a numerically determined LED illuminant spectrum [12][13][14][15]. However, few reports have described studies examining LED source development as a transfer standard with emphasis on extending the spectral range of the spectrum [16]. To resolve the shortcomings described above, we developed a 2π standard LED for use in spectral measurements to avoid spectral-shape-related uncertainty to the greatest degree possible [9].…”