The main difference between a "white source" and a solar simulator is the relative spectral distribution of these 2 sources. Solar simulator simulates more or less perfectly the solar spectrum including UV and IR radiations, that is not the case of a "white source". Using this last one you determine the efficiency of your cells for the visible light with a spectral distribution that can be very different of the visible solar spectrum... and introduce significant errors in your estimation.

I think your method could be used for periodical routine check of your cells, assuming that the degradation of the cells is wavelength independent. Nevertheless, my experience shows that degradation in the UV and short wavelengths in the visible is more rapid that can also introduce significant errors for relative efficiency determination.

I hope these few remarks will be helpful for you.

Good luck for your future researchs

Didier Gillotay

Another important point to consider is that the LUX meter is assumed to respond only to the visible light part of the spectrum of the radiation source. So, i assume it will measure only apart of your white light source as white light sources may radiate also in a broader spectrum band than the visible light. Accordingly the input photon power may be greater than that measured by the lux meter. So, even the efficiency which you measured may be over estimated since the incident radiation power is basically greater than that indicated by the LUX meter.

Otherwise i fully agree with Didier.

Best wishes

Typical true solar irradiance of 900W/m2, corresponding to 90mW/cm2 (or 0.9mW/mm2), may be used to judge if your LUX meter is adequate for your research

Best Wishes

Dawei

Thank You Dr. Didier Gillotay, Dr. Abdelhalim Zerky and Dr.Dawai Liang to sharing the valuable suggestions.

Thank You

You are welcome...

Didier

Hi all,

If we use LUX meter to determine the illumination of white light LED solar simulator system, do we have to measure at every specific wavelength (say 600 nm only, then the rest, one by one) or we can measure the whole spectral region (say 400-800 nm) in one shot?

Thank you.