US 12,455,533 B2
Holographic display device
Hyeonseung Yu, Suwon-si (KR); Hoon Song, Yongin-si (KR); Jungkwuen An, Suwon-si (KR); and Hongseok Lee, Seoul (KR)
Assigned to SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR)
Filed by SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR)
Filed on Oct. 15, 2021, as Appl. No. 17/502,316.
Claims priority of application No. 10-2021-0040539 (KR), filed on Mar. 29, 2021.
Prior Publication US 2022/0308526 A1, Sep. 29, 2022
Int. Cl. G03H 1/22 (2006.01)
CPC G03H 1/2294 (2013.01) [G03H 2226/02 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A holographic display device comprising:
a spatial light modulator representing a partial complex domain and reproducing a hologram by diffracting light; and
a processor configured to control the spatial light modulator by employing an algorithm for calculating hologram information according to representation of the partial complex domain of the spatial light modulator,
wherein the spatial light modulator comprises a first spatial light modulator and a second spatial light modulator arranged parallel to each other, each of the first spatial light modulator and the second spatial light modulator comprising a plurality of pixel arrays, and
wherein the spatial light modulator represents the partial complex domain by a combination of the first spatial light modulator and the second spatial light modulator, and
wherein the first spatial light modulator and the second spatial light modulator share a common optical axis;
wherein the spatial light modulator is provided to represent 50% or more and less than 100% of full complex information; wherein the algorithm sets a phase of a target hologram to be constant or random, and calculates and applies a CGH on a surface of the spatial light modulator by back propagating the phase of the target hologram; wherein the algorithm allows the phase of the target hologram to be reproduced by representing a limited random value, within a limit allowed by a complex representation range of the spatial light modulator; wherein the algorithm, when setting the phase of the target hologram to be random, limits a phase of the CGH calculated on the surface of the spatial light modulator to fit to the partial complex domain that is representable by the spatial light modulator, by back propagating the phase of the target hologram; wherein the algorithm reproduces the hologram with a limited random phase by optimizing such that a difference between an amplitude of a reconstructed hologram reproduced from a limited CGH having a limited phase and an amplitude of an initially set hologram becomes less than a target value.