The invention discloses a
hybrid encryption and decryption method based on a
chaotic system and an optical key, and the
encryption method comprises the steps: generating a
chaotic key through the initial information of a to-be-encrypted object and an initial key, and generating a
chaotic sequence for the chaotic key through employing a five-dimensional Hamiltonian conservative chaotic
system (FHCCS); scrambling and grouping the initial information according to the chaotic sequence, and selecting a corresponding
diffraction distance as an optical key; generating a computer-generated hologram by adopting a layered angular spectrum method according to the
diffraction distance; encrypting the computer-generated hologram by adopting the chaos sequence to obtain an optical
password book; and encrypting a
ciphertext of the optical
password book by using the chaotic sequence to obtain a
ciphertext of a final encrypted object. According to the method, an
encryption mode of combining the optical key and the chaotic key is adopted, and the optical
password book inherits the advantages of efficient
information storage, high decryption speed, high parallelism and the like of
optical encryption, and has the advantages of high
shear resistance,
high security and the like which are not possessed by a traditional password book.