We demonstrate the storage of 1000 holograms in a memory architecture that makes use of different wavelengths for recording and readout to reduce the grating decay while retrieving data. Braggmismatch problems from the use of two wavelengths are minimized through recording in the image plane and using thin crystals. Peristrophic multiplexing can be combined with angle multiplexing to counter the poorer angular selectivity of thin crystals. Dark conductivity reduces the effectiveness of the dual-wavelength method for nonvolatile readout, and constraints on the usable pixel sizes limit this method to moderate storage densities.
What is believed to be a novel holographic design for read-only memory systems allows a compact low-cost consumer drive within a 10 mm drive height, using a lensless phase conjugate readout and a combination of polytopic and angle multiplexing. A two-step mastering method enables production of high-efficiency holographic masters, and fast replication is possible by using only a series of plane-wave illuminations. Mastering and replication techniques are verified experimentally with an array of 125 holograms with no measured bit errors.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.