Computing Of Sub-hologram Based On LCOS And Its Application In 3D Display

The classic holography can record and reconstruct 3D object by interference and diffraction. Under the illumination of light to reconstruct, we can see the reconstructed object through the hologram, just as we see the real object. Thus, holography has a bright future in realizing 3D display. However, in the recording process of classic holography, high intensity and high interference quality light source is needed, high stable optical system and analog recording medium like film or interfering board are also needed. Besides, the recording time is long. These problems have limited the application of the classic holography in dynamic 3D display.By using computer's computing to simulate the wavefront of the light, computational holography avoid the complicated recording process of the classic holography. But there are still some bottleneck problems in realizing dynamic 3D display, especially the large computational amount and data amount. This paper tries to reduce the computational amount and data amount in computational holography. It refers to the sub-hologram approach of the SeeReal company, and uses phase-only LCOS spatial light modulator to reconstruct. The main research works are as follows:First, research a algorithm named "phase compensation algorithm" for sub-hologram, it is proved by experiments that it can be used to reconstruct a spatial point well. When used to test phase modulation quality of the LCOS, it also works well.Second, two approaches of superposing sub-holograms have been tested. The experimental results show their feasibility, especially when there are few spatial points to be reconstructed.Third, by superposing sub-holograms,3D display of limited view point is realized. After that, to magnifying the small reconstructed 3D object we discuss several approaches using optical lens.