Bacteriorhodopsin as a high-resolution, high-capacity buffer for digital holographic measurements

Abstract

Recent trends in optical metrology suggest that, in order for holographic measurement to become a widespread tool, it must be based on methods that do not require physical development of the hologram. While digital holography has been successfully demonstrated in recent years, unfortunately the limited information capacity of present electronic sensors, such as CCD arrays, is still many orders of magnitude away from directly competing with the high-resolution silver halide plates used in traditional holography. As a result, present digital holographic methods with current electronic sensors cannot record object sizes larger than several hundred microns at high resolution. In this paper, the authors report on the use of bacteriorhodopsin (BR) for digital holography to overcome these limitations. In particular, BR is a real-time recording medium with an information capacity (5000 line-pairs/mm) that even exceeds high resolution photographic film. As such, a centimetre-square area of BR film has the same information capacity of several hundred state-of-the-art CCD cameras. For digital holography, BR temporarily holds the hologram record so that its information content can be digitized for numeric reconstruction. In addition, this paper examines the use of BR for optical reconstruction without chemical development. When correctly managed, it is found that BR is highly effective, in terms of both quality and process time, for three-dimensional holographic measurements. Consequently, several key holographic applications, based on BR, are proposed in this paper.

Electron Transfers and Holographic Molecules: Why Neuroscientists Should Take Quantum Phenomena into Consideration

“…It may be, then, hypothesized that such phenomena take place in living organisms. This is even more plausible, as photosensitizer pigments, such as rhodopsins of bacteria, are used for recording holographic data (Oesterhelt et al, 1991;Barnhart et al, 2004). Any protein involved in the process of electron transfers might also function as a "holographic molecule".…”

“…These molecules are used as recording medium of holographic data with a resolution higher than the best photographic films (Barnhart et al, 2004). The example of bacteriorhodopsins has opened new horizons since electrons are quantum particles endowed with characteristics similar to photons (Li et al, 2008).…”

Rewritable holographic image storage with BRD96N film

“…Bacteriorhodopsin (BR) is one kind of biological photochromic material. Because of the long time evolution in the nature, the BR get a lot of advantages comparing with other photochromic materials, such as excellent fatigue resistance (more than one million times), high sensitivity and high thermal stability [5,6] .…”

Recent Developments of PIV towards 3D Measurements

“…Bacteriorhodopsin (BR) is a photochromic material whose use as a reusable, high-resolution (5000 lines/mm), real-time recording material in velocimetry was proposed in 2002 [45]. Its main weakness, however, is the photoinduced erasure during readout.…”

“…BR can only be used for temporary storage of holographic information since the produced transparency decays at room temperature within a few minutes. Strategies for hologram recording and data retrieval have been proposed [46]. In practice, an off-axis reference beam and a forward-scattering setup have proven useful to cope with the material's low sensitivity (a few mJ/cm 2 at 532 nm) [47][48][49] -after initial tests with a sidescattering configuration [50].…”