Improved performance of volume holographic sol‐gel materials—refractive index modulations in the 10–2 range, diffraction efficiencies near 100 %, and low levels of noise scattering—are reported that arise from the incorporation of Zr‐based high refractive index species capable of diffusing from dark to bright fringes of the interference pattern (see figure).

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The design of newer ultrasonic imaging systems attempts to obtain low-cost, small-sized devices with reduced power consumption that are capable of reaching high frame rates with high image quality. In this regard, synthetic aperture techniques have been very useful. They reduce hardware requirements and accelerate information capture. However, the beamforming process is still very slow, limiting the overall speed of the system. Recently, general-purpose computing on graphics processing unit techniques have been proposed as a way to accelerate image composition. They provide excellent computing power with which a very large volume of data can easily and quickly be processed. This paper describes a new system architecture that merges both principles. Thus, using a minimum-redundancy synthetic aperture technique to acquire the signals (2R-SAFT), and a graphics processing unit as a beamformer, we have developed a new scanner with full dynamic focusing, both on emission and reception, that attains real-time imaging with very few resources.