Holographic display device with 2D encoding

1. A holographic display comprising light sources in a 2D light source array, lenses in a 2D lens array, a spatial light modulator (SLM) and a beamsplitter, the 2D light source array comprising m light sources per lens, the light sources being in m-to-one correspondence with the lenses, where the beamsplitter splits the rays leaving the SLM into two bundles, one of which illuminates virtual observer windows for m left eyes and the other illuminates virtual observer windows for m right eyes, in a time sequential manner, synchronized with the display SLM, m having a value of greater than 1, the display realizing a time multiplexing for m observers and a spatial multiplexing for the left eye and the right eye for each one of the m observers.

2. The holographic display of claim 1 , in which 2D-encoding provides holographic reconstruction simultaneously in the horizontal and the vertical directions.

3. The holographic display of claim 1 , in which the beamsplitter is a prism array or in which the beamsplitter is a 1D array of vertical prisms or in which the beamsplitter is a prism array being integrated in or directly on the SLM, as a refractive, diffractive, or holographic prism array.

4. The holographic display of claim 1 , in which the beamsplitter is a second lens array or in which the beamsplitter is a barrier mask or in which the beamsplitter is a diffractive optical element.

5. The holographic display of claim 1 , in which the beamsplitter is after or before the SLM.

6. The holographic display of claim 1 , in which each light source is imaged to an observer plane by its associated lens.

7. The holographic display of claim 1 , in which for a given observer, a pitch of the light source array and a pitch of the lens array are such that all light-source images coincide in an observer plane i.e. a plane which contains two virtual observer windows.

8. The holographic display of claim 1 , in which an additional field lens is present.

9. The holographic display of claim 1 , in which a pitch of the lens array is similar to the typical size of a sub-hologram in order to provide sufficient spatial coherence.

10. The holographic display of claim 1 , in which the light sources are small or point light sources.

11. The holographic display of claim 1 , in which the lens array is refractive, diffractive or holographic.

12. The holographic display of claim 1 , in which holograms for the left and the right eye are interlaced column by column.

13. The holographic display of claim 1 , in which a pitch of the beamsplitter is the same as, or an integer multiple of, a pitch of the SLM, or in which a pitch of the beamsplitter is slightly different to a pitch of the SLM or slightly different to an integer multiple of a pitch of the SLM in order to accommodate perspective shortening.

14. The holographic display of claim 1 , in which light-source tracking is implemented.

15. The holographic display of claim 3 , in which the prism array generates one intensity enveloping sinc-squared function maximum at the position of virtual observer windows for m left eyes and another intensity enveloping sinc-squared function maximum at the position of virtual observer windows for m right eyes.

16. The holographic display of claim 15 , in which the height of a virtual observer window (VOW) is smaller or equal to the vertical periodicity interval associated with diffraction at the SLM, and the width of a virtual observer window is smaller or equal to the horizontal periodicity interval associated with diffraction at the beamsplitter.

17. A method of generating a holographic reconstruction comprising the step of using the display device of claim 1 .