Study On Time Response Characters Of Holographic Plate

The time response of holographic plate to pulse laser is very important for holography of fast moving objects, especially for the particle field holography. Based on this question, this thesis conducts a detail research on the reciprocity law failure of holographic plate when it is exposed to pulse laser.1. In theory, due to the Gurney-Mott principle, this paper sets up a probabilistic model to state the main photochemical reaction during the exposure process, through this model, the time response character of holographic plate, as measured by the photographic density, is taken to be a function of exposure time interval duration, the function can be used to qualitative analysis the time response character of holographic plate.2. The dominant photochemical reactions for the sensitization process are discussed through changing parameters of the model. A new explanation for shoulder-part drooping of D-Log(E) curve can be also derived from the model. Furthermore, the model puts forward a viewpoint that the key factor which decides the optic density is the time of photo electron trapping silver ions. Meanwhile, the numerical simulation methods are taken to study the influence of reciprocity law failure on holography.3. A series of experiments are carried out on the time response of holographic plate. Three kinds of experiment equipments are designed to produce long duration laser pulse, microsecond laser pulse and ultrashort laser pulse, the exposure energy differences of each experiment equipment are limited to 4%. Especially, a shutter system consist of quickly-open-shutter and exploding-close-shutter can get the extinction ratio of 50000.4. The identical exposure energy curve of Slavich VRP-M plate is obtained by experiment, the experiment result is in accordance with that of the theoretical research, which shows that the photochemical reaction in holographic emulsion can be simulated by a probabilistic model and arrive at a conclusion: if the exposure time is shorter than the "dead time" of photoelectron or longer than "decay time" of single silver atoms, the holographic plate should suffer severe reciprocity law failure. In addition, for getting the same optic density, ultrashort pulse exposure need 10 times more exposure energy than that of no reciprocity failure exposure.