Abstract is exactly "Time delay cosmography is an approach that has emerged in the last decade to estimate the Hubble constant, i.e., the current expansion rate of the universe. Its main ingredient is to obtain the photometry of point sources in gravitational lenses. This requires deconvolution of observations acquired by space or ground-based telescopes. In this work, a new image deconvolution method called STARRED is proposed, which uses a Point Spread Function narrower than the original one. At the same time, the latter is produced using NarrowPSFGen, a technique developed in this thesis."