Research on spectrum image encryption and anti-cou

Research on spectrum image encryption and anti-counterfeiting in holographic printing (VIII)

Chapter 5 Conclusion

according to the Fourier transform of the lens, a transparent image (secret mark) located on the front focal plane of the lens can obtain the spectrum of the image on the rear focal plane after Fourier transform and focus on a small area near the focus, so the encrypted pattern can be Fourier transformed, The spectrum is cleverly recorded in a certain position of the rainbow hologram and displayed in some optical form of the image. However, due to the difference between the holographic recording of passwords and the making of ordinary holograms: the method of replacing steel with light materials in shipbuilding is different, and it is difficult for peers to infer the mathematical model of the original object and its manufacturing method from the displayed optical image. Therefore, the spectrum characteristics can be summarized as follows:

① the spatial distribution form of the object wave spectrum is completely different

now follow the author's steps to analyze 1. ② it is difficult to infer the form of the object wave from the image of the spectrum, so we cannot know the shape of the object that produces the spectrum. Therefore, using optical means to make Fourier spectrum as an encrypted password on the hologram will effectively strengthen the anti-counterfeiting performance of holographic printing images

conclusion of Chapter 6

in the whole process of writing this article, we have received the careful guidance of Professor Yang Gao. Here we only express our heartfelt thanks. In addition, due to the limitations of time, personal level and other factors, the deficiencies and even fallacies in the article are inevitable. Please criticize and correct them more

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