Abstract: Disclosed is a photopolymerizable holographic recording medium for data storage that comprises colloidal metal, and which exhibits a threshold for a second stage polymerization which is substantially insensitive to the light used for both forming holograms and interrogating the medium during servo and/or read events. Also disclosed is a method of preparing said photopolymerizable holographic recording medium. Also disclosed is a method for preparing a colloidal without additives in a viscous medium.

Abstract: An apparatus and a method for acquiring an image of skin topology. The apparatus comprises at least one light source, configured to form a source beam; at least one illuminating diffractive optical element (DOE) disposed in the optical path of the source beam, configured to diffract the source beam, thereby forming an illuminating beam; a skin contact surface, disposed in the optical path of the illuminating beam, configured to at least partially reflect the illuminating beam at regions of the boundary between the skin contact surface and skin that are not in contact with skin, thereby forming a reflected beam; at least one imaging diffractive optical element (DOE), disposed in the optical path of the reflected beam, configured to diffract the reflected light beam, thereby forming an image beam; and a sensor array, configured to receive at least a portion of the image beam and thereby to detect the acquired image.

Abstract: A holographic optical filter that includes an optical recording medium for storing several multiplexed reflection holograms that are formed by successive interference between two or more collimated object beams with a common collimated reference beam. The object beams are incident to the recording material at a series of angles chosen to provide reflection efficiency over the desired filed of view at the specified wavelength.