Fig. 4: Experimental demonstration of digital “7”.
From: Compact optical convolution processing unit based on multimode interference
a The input image of digit “7” from the MNIST database. b Sequential ideal (orange line) and experimental (blue line) electronic waveforms. d Ideal and experimental convolution output waveform with the kernel of \(\left[\begin{array}{cc}1 & 0\\ 0 & 1\end{array}\right]\). c, e are magnifications of (b) and (d) at 23.43–26.95 ns, respectively. f The recovered feature image.
