So far, we have focused on the impact of the side group conjugation on the photoswitching activity. Next, we explore the effect of electronic conjugation in the backbone of DTE photoswitches. The impact and role of the backbone conjugation on photoswitching has been demonstrated in thieno [3,4-b]thiophene-based systems. This study shows how the relative degree of conjugation at the backbone with respect to that in the side groups notably affects orbital energies and localization, eventually dictating the photocyclization capabilities.