Optical Lens "cat Eye" Effect Analysis And Short-range Exchange Of Information

Because of the nature of the 'cat-eye'effects in optical lenses, its back scattering will be strongly strengthened and the precision of an active laser surveillance will be greatly enhanced. Hence, it is needed to study the 'cat-eye'effects thoroughly. In this dissertation, it is pointed out that the reflect wave power is quite different if the photo-sensing surface (or a cross-reticle) on the different position near the focal plant. The properties of the focus-deviations in the 'cat-eye'systems are carefully studied, which include two different kinds, i.e., the front focus-deviating system and the behind focus-deviating system. It is shown that the relation between the reflect wave power and the focus-deviations is different in those systems through theoretical analysis. With the help of the Matlab, numerical simulation is also made. The final result shows that the reflect wave power will greatly decrease in the front deviating focus system. On the other hand, the reflect wave power is relatively slowly decreased in the behind focus-deviating system. Therefore, it is possible to employ this decreasing curve to the transfer of the information. The main work of the dissertation lies in: firstly, the ray-tracing method is used to calculate the 'cat-eye 'effect with the system being focus-deviating; so the position and the angle of optical ray at the exit pupil are obtained. Secondly, these data can be input into Matlab for numerical simulation. The different systems with different focus are chosen, for example the focus is 20 mm, 25mm,30mm et al and the variance of the factor βin those systems is carefully studied. Finally, two experiments including static and dynamic experiments are proposed according to the principle of short-distance information exchange, in which the behind focus-deviating system is used. In the static experiment, in which a reflecting surface is used instead of the photo-sensing surface, it is obviously shown the different decreasing rates of the two focus-deviating systems. In the dynamic experiment the reflecting surface is controlled by a mini speaker, the transfer of information is realized in a short distance.