To take a large and high-grade hologram, have been numerous scientific workers' interested topics. Since the stability of
the holographic plate, objective table's stability, object's stability, optical elements' stabilities, etc, aren't easily
supervised and controlled precisely, the laser holographic technique has progressed at a slow pace.
Precise micropressure measuring system, an application of laser technology, is introduced as a method for monitoring
holographic plates' stability. This system firstly brings the pressure sensor into the laser holographic experiments, and
uses the soft Kingview to design the programs for controlling the pressure sensor, so that the system can real-time
monitoring and real-time adjusting the laser holographic plates' stability. Being verified by experiments, this experiment
has achieved good results, for example, making a larger hologram, saving the time taken from the original 1-2 days to
present of 0.5-1.5 hours, that is to say those above-mentioned measures raise the success rate of making large holograms
to some extent.
Water-resisting red-sensitive photopolymer with simple reprocessing has high sensitivity, high diffraction efficiency (>80%) and large refractive index modulation. Sensitivity and resolution is increased by using compound spectral sensitization compound coinitiator and compound monomers. The polymerization of the monomer can be controlled, and so the holograms preserved in the natural environment for a long time do not disappear. The photopolymer holographic recording materials without hidden reaction have good physical and chemical stability. The result of research indicates that the holographic recording plates have better real-time character. The photochemical polymerization mechanism and the effects of the components on the photopolymerization rate are investigated, and other characteristics about this material are also analyzed. In addition, the photopolymer is harmless and pollution-free, and so the photopolymer has large practical value and prospects of wide applications.
In this paper, a blue-sensitive photopolymer holographic recording material was prepared. The visible-light sensitive photoinitiating system was composed of sensitizer, initiator, hydrogen-donor, monomer and binder. Compound sensitizing as a new method for improving exposure sensitivity of this material was proposed. Experiments results indicate that compound sensitizing significantly increased the exposure sensitivity from about 55mJ/cm2 to 40 mJ/cm2, while without any affection to the maximum obtainable diffraction efficiency. More than 85% of transmission grating diffraction efficiency can be attained as a very simple post process was performed. Mechanisms of polymerization and hologram formation were discussed. The holograms, with a good physical and chemical stability under ambient circumstance, have much potential in optical communication, such as filters and switches.
The basic starting point of the digital hologram’s image-forming system is to employ two-dimensional medium for expressing three-dimensional image or recovering three dimensional objects. By virtue of the computer coding technology, we reconstruct object’s reproduction image, and use red-sensitive photopolymer to make hologram. In this paper, we discuss two record devices, that is, the Charged Coupled Device and the digital camera. We mainly focus on two kinds of spatial light modulator, and choose one to project images. As for the holographic record material, we use a sort of self-made photopolymer, which is a contamination free record material. In the experiment, we have received certain fine results.