Hologram formation

Figure 5. Schematic arrangement for hologram formation with an electron biprism. A plane wave illuminates the specimen placed off-axis. After the object lens a wire is placed between two earthed plates. The wire is the electron optical analog of a Fresnel biprism and causes the unperturbed and perturbed waves forming the electron hologram to interfere. The object phase-shift causes a displacement in the hologram fringes, and is thus observable.

The PR effect was first observed in 1966 as an undesirable effect in an EO crystal, LiNb03 [1], It was soon realized that this effect is reversible and its PR mechanism was then identified [2,3], These PR materials can be applied to high-capacity optical memories, dynamic hologram formations, massive interconnections, high-speed tunable filters, and true-time relay lines for phase array... 

Uniform preillumination is discussed in the literature in two different time regimes. Fast diffraction response is obtained from materials which are illuminated uniformly and intensely for a few seconds before a second writing beam is used to pattern the intensity in the material and begin hologram formation. This maximizes the mobile hole density in the material at the time of hologram formation and helps to reach the charge generation limit of Eq. (1). 

Adhami R. Lanteigne, D. Gregory D. (1991). Photopolymer hologram formation theory. Microwave and optical technology letters, Vol. 4, No. 3,106-109. 

Crawford W (1979) The keepers of light. Morgan and Morgan, New York, pp 69-73 Djouani F, Israeli Y, Frezet L et al (2006) New combined polymer/chromium approach for investigating the phototransformations involved in hologram formation in dichromated poly(vinyl alcohol). J Polym Sci Polym Chem 44 1317-1325... 

MAH 08] Mahilny U.V., Marmysh D.N., Tolstik A.L. et al., Phase hologram formation in highly concentrated phenanthrenequinone-PMMA media . Journal... 

Improved Photopolymers for Holographic Recording. Mechanism of Hologram Formation. 

Shindo, D. Murakami,Y. Hirayama,T. (1998) Application of electron hologram to morphological analysis of spindle-type hematite particles, Mater. Transact. JIM 39 322-324 Shindo, H. Huang, P.M. (1984) Catalytic effects of manganese (IV), iron(III), aluminum, and silicon oxides on the formation of... 

Particle size data were obtained for selected test conditions directly from holograms and photographs. Spray measurements were made at an axial distance of approximately 2.5 cm (1 in.) from the injector where spray formation processes had been completed and spherical droplets formed. 

Mean droplet size as measured from the holograms and photographs was consistent with the visual observations of spray formation and spray quality. 

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