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In this work we propose a non-invasive alternative to cataracts surgery by means of manipulating the wavefront of the incident light. We show a two-fold improvement in the Strehl ratio of the ocular Point Spread Function.

In this work we present the Adaptive Optics Visual Simulator (VAO) and show the potential of Adaptive Optics in visual diagnostic and simulation, for a complete and fully personalized vision characterization.

In this work we propose a non-invasive alternative to cataracts surgery by means of manipulating the wavefront of the incident light. We show an improvement of 80 in the Strehl ratio of the ocular Point Spread Function.

Cataracts are a common ocular pathology involving an increase in the amount of intraocular light scattering. This causes vision impairment by blurring and reducing the contrast in retinal images. The current treatment for this pathology is cataract surgery, which is an invasive procedure with possible side effects, such as corneal edema, infection or retinal detachment among others. In this work, we propose a non-invasive approach to improve vision through the cataractous lenses by manipulating the wavefront of the incident light. By using a fluorescent signal as feedback (similar to the inherent fluorescence of the lipofuscin pigment at the retina) we show the capability of improving the point spread function (PSF) of the eye in a single pass through the artificial eye’s optics, while the feedback signal is measured in a double-pass configuration, making the whole system completely non-invasive, opening new possibilities for real-time vision correction through cataracts with wearable devices.

Ghost imaging is an unconventional optical imaging technique that reconstructs the shape of an object combining the measurement of two signals: one that interacted with the object, but without any spatial information, the other containing spatial information, but that never interacted with the object. Ghost imaging is a very flexible technique, that has been generalized to the single-photon regime, to the time domain, to infrared and terahertz frequencies, and many more conditions. Here we demonstrate that ghost imaging can be performed without ever knowing the patterns illuminating the object, but using patterns correlated with them, doesn't matter how weakly. As an experimental proof we exploit the recently discovered correlation between the reflected and transmitted light from a scattering layer, and reconstruct the image of an object hidden behind a scattering layer using only the reflected light, which never interacts with the object. This method opens new perspectives for non-invasive imaging behind or within turbid media., 5 pages, 4 figures

Spatial Light Modulators (SLMs) are widely used in several fields of optics such as adaptive optics. SLMs based on Liquid Crystal (LC) devices allow a dynamic and easy representation of two-dimensional phase maps. A drawback of these devices is their elevated cost, preventing a massive use of the technology. We present a more affordable approach based on the serial arrangement of vertical aligned LC devices, with characteristics of phase modulation similar to a widely used parallel aligned LC device. We discuss the peculiarities of the approach, the performance and some potential areas of applications.

We propose a novel technique for imaging through opaque multiply scattering media, based on mesoscopic correlations between the reflected and transmitted speckle patterns.

When light propagates in a turbid medium, multiple scattering prevents it from reaching depths much greater than the mean free path. This limited propagation presents a problem for many fields where optical energy delivery through scattering media is critical, such as energy conversion in dye-sensitized solar cells, light-based medical techniques, or white LEDs. In this work we show that wavefront shaping techniques can significantly increase the delivery of optical energy through strongly scattering media.