Fig. 1. Principle of computational spectral imaging technology based on broadband filtering modulation

Fig. 2. Spectral transmittance curve of band-stop filter. (a) Spectral transmittance curve of typical band-stop filter; (b) spectral transmittance curves of block filter arrays

Fig. 3. Standard reference spectrum

Fig. 4. Diagram of simulation process

Fig. 5. Main error types of spectral transmittance. (a) Random error of whole band; (b) optical density error in cutoff band; (c) half-peak full width error of band resistance band; (d) central wavelength position deviation of band blocking band

Fig. 6. Accuracy of spectrum reconstruction encoded by symmetric tridiagonal matrix with errors. (a) Random error of whole band; (b) optical density error in cutoff region; (c) FWHM error; (d) central wavelength position error; (e) reconstructed spectra obtained by adaptive regularization algorithm with generalized cross-validation

Fig. 7. Comparison of spectral reconstruction accuracy between arbitrary spectral transmittance coding and symmetric tridiagonal spectral observation matrix coding. (a) Transmittance curves of 16 arbitrary spectra; (b) comparison of accuracy of reconstructed spectra encoded by two kinds of spectral transmittance

Fig. 8. Accuracy of spectral reconstruction by large-scale tridiagonal observation matrix at different number of bands. (a) Number of bands is 160; (b) number of bands is 640; (c) number of bands is 1280