The recently introduced virtual fluorescent standard (VFS) method for measuring an optical property of a sample treated by fluorescent whitening agent (FWA) was applied to a printed sample on FWA-treated paper. The primary difficulty of this application is that the bispectral luminescent radiance factor of the paper substrate is specifically modified by the ink films printed and each sample has the specific bi-spectral luminescent radiance factor. In this study, the difficulty is handled by two different, orthodox and abridged, approaches. In the orthodox approach, the effective bi-spectral luminescent radiance factor of a printed sample is estimated based on the effective spectral transmittance, which is also estimated, of the ink films printed. In the abridged approach, the effective spectral transmittance of the ink films is considered to be spectrally neutral and accordingly the effective bi-spectral luminescent radiance factor of the printed sample is regarded as relatively identical or close to that of the paper. The performances of the VFS method by both approaches were examined with 28 samples printed by a laser printer with 7 primaries Y, M, C, K, R, G, B at 25, 50, 75, 100% dot areas on FWA-treated paper. The results show that the performances of both approaches are remarkable at least for those samples and the abridged approach has the performance close to that of the orthodox approach for most of the samples.
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