| In laser's actual application, to meet different request, people usually need to shape the intension of laser beam. For example, shape the laser beam to rectangle frame or ring etc. The traditional optical elements are difficult to realize those kinds of conversion, and the efficiency of the calculation hologram is too low. Because the computer optical elements can shape the laser beam to arbitrary shape, so, in this paper we mainly study the design and the experiment of the computer optical elements.In this paper we designed the relief height of the computer optical elements mainly based on the geometrical theory and the scalar quantity diffractive theory. Based on the geometrical theory, we achieved the height of phase relief that can shape the laser beam into 4 square spots,square frame,1 square spot; With the computer simulation and drawing program, the diffraction patterns are gotten in this paper, the results agreed with the anticipated diffraction patterns; in this paper we also discussed the affects to the diffraction patterns by changing some parameters.In this paper we also designed the computer optical elements based on the scalar quantity diffractive theory, which can change the laser beam into a square frame.We mainly refered to the one of those improved algorithms of Gerchberg-Saxton(GS).With the computer simulation and drawing program, the simulated diffraction patterns were gotten in this paper, the results agreed with the anticipated diffraction patterns; in the paper we also design the computer optical elements that can shape the laser beam into a double circle shape,a lamp shape and so on. Those simulated results agreed with the anticipated diffraction patterns.In this paper we compared the simulated results of the computer optical elements based on the two different theories, and summarized the advantages and disadvantages of the two different theories. And we did the theoretical analysis with LCD cell to achieve the phase distribution of COE.That will bring reference meaning to the designation of the computer optical elements.In chapter 5 we proved the accuracy of the design theories and the theoretical deduces through the experiments with film and general LCD cell. |
