Holographic reproduction device, holographic reproduction system and holographic display system

The present disclosure provides a holographic reproduction device, a holographic reproduction system, and a holographic display system. The holographic reproduction device includes a first light source configured to provide first coherent light; at least one electrically addressed liquid crystal display panel configured to display a holographic interferogram, so that the first coherent light is diffracted when the first coherent light transmits through the holographic interferogram to present a holographic reproduction image. A liquid crystal material of the electrically addressed liquid crystal display panel includes smectic liquid crystal.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present disclosure claims the priority of Chinese Patent Application No. 201910579650.9, filed on Jun. 28, 2019, the contents of which are incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates to the field of holographic display technology, and in particular, to a holographic reproduction device, a holographic reproduction system, and a holographic display system.

BACKGROUND

More and more attention has been paid to stereoscopic display based on holographic information. During a recording process of holographic information, two beams, i.e. a reference beam and an object beam, which transmit along different paths, interfere with each other to form an optical interference pattern. The optical interference pattern causes a chemical or physical change in the photosensitive recording medium so that information about a recorded object is recorded in the recording medium. During the holographic reproduction process, a reference beam similar to the reference beam used for recording is incident onto the recording medium, and the reference beam transmitting through the optical interference pattern in the recording medium is diffracted to reproduce the object beam, thereby reproducing information.

SUMMARY

As an aspect, a holographic reproduction device is provided. The holographic reproduction device includes: at least one electrically addressed liquid crystal display panel configured to display a holographic interferogram or holographic interference image; and a first light source configured to provide first coherent light which is diffracted when transmitting through the holographic interferogram to present a holographic reproduction image; wherein a liquid crystal material of the electrically addressed liquid crystal display panel includes smectic liquid crystal.

In an embodiment, the electrically addressed liquid crystal display panel is a reflective liquid crystal display panel, the first light source is on a viewing side of the electrically addressed liquid crystal display panel, and a side of the electrically addressed liquid crystal display panel distal to the viewing side is provided with a reflective layer.

In an embodiment, the viewing side of the electrically addressed liquid crystal display panel is provided with a first transflective structure and a first reflective structure, the first transflective structure is configured to transmit a portion of the first coherent light received from the first light source to the first reflective structure, the first reflective structure is configured to reflect light received from the first transflective structure to the first transflective structure, and the first transflective structure is further configured to reflect light received from the first reflective structure to the electrically addressed liquid crystal display panel, and transmit light reflected by the reflective layer of the electrically addressed liquid crystal display panel.

In an embodiment, the electrically addressed liquid crystal display panel is a transmissive liquid crystal display panel, and the first light source is on a side of the electrically addressed liquid crystal display panel distal to a viewing side.

In an embodiment, the holographic reproduction device includes N electrically addressed liquid crystal display panels, where N is greater than or equal to 2. All of the electrically addressed liquid crystal display panels are sequentially spliced, such that pictures displayed by all of the electrically addressed liquid crystal display panels are spliced to form the holographic interferogram, and any two adjacent electrically addressed liquid crystal display panels are spliced together to form a dihedral angle larger than or equal to 90 degrees and smaller than 180 degrees.

In an embodiment, among all of the electrically addressed liquid crystal display panels, a side, distal to the viewing side, of each of the electrically addressed liquid crystal display panels except a last electrically addressed liquid crystal display panel is provided with a second transflective structure. A side of the last electrically addressed liquid crystal display panel distal to the viewing side is provided with a second reflective structure. The first light source is on a side of a second transflective structure corresponding to a first electrically addressed liquid crystal display panel distal to the viewing side. The second transflective structure on a side of the first electrically addressed liquid crystal display panel distal to the viewing side is configured to transmit a portion of the first coherent light received from the first light source to the first electrically addressed liquid crystal display panel, and transmit another portion of the first coherent light received from the first light source to a second transflective structure on a side of a second electrically addressed liquid crystal display panel distal to the viewing side, the second electrically addressed liquid crystal display panel being adjacent to the first electrically addressed liquid crystal display panel. A second transflective structure on a side of an ithelectrically addressed liquid crystal display panel distal to the viewing side is configured to reflect a portion of received coherent light to the ithelectrically addressed liquid crystal display panel, and transmit another portion of the received coherent light to a second transflective structure or the second reflective structure on a side of a (i+1)thelectrically addressed liquid crystal display panel distal to the viewing side, the (i+1)thelectrically addressed liquid crystal display panel being adjacent to the ithelectrically addressed liquid crystal display panel, and 1≤i≤N−1. The second reflective structure on a side of an Nthelectrically addressed liquid crystal display panel distal to the viewing side is configured to reflect received light to the Nm electrically addressed liquid crystal display panel.

In an embodiment, a second transflective structure on the side of the first electrically addressed liquid crystal display panel distal to the viewing side has a light transmittance of

1N,
and the second transflective structure on the side of the ithelectrically addressed liquid crystal display panel distal to the viewing side has a light transmittance of

In an embodiment, N is equal to 2.

In an embodiment, the first light source is a laser light source.

In an embodiment, the holographic reproduction device further includes: a first len, on a light outgoing path of the first light source and configured to expand light emitted from the first light source; and a second len, on the viewing side of the electrically addressed liquid crystal display panel and configured to converge light from the electrically addressed liquid crystal display panel.

In an embodiment, the holographic reproduction device is a 3D billboard or a 3D electronic label.

As another aspect, a holographic reproduction system including the above holographic reproduction device is provided.

As another aspect, a holographic display system including the above holographic reproduction system is provided.

In an embodiment, the holographic display system further includes a holographic recording system configured to generate a holographic interferogram of a recorded object, and send display data corresponding to the holographic interferogram to the electrically addressed liquid crystal display panel.

In an embodiment, the holographic recording system includes a second light source, a third transflective structure, a third reflective structure and a holographic plate. The second light source is configured to provide second coherent light. The third transflective structure is configured to reflect a portion, as a reference beam, of the second coherent light received from the second light source to the holographic plate, and transmit another portion of the second coherent light received from the second light source to the third reflective structure. The third reflective structure is configured to reflect light received from the third transflective structure to the recorded object, so that the light incident onto the recorded object is reflected by a surface of the recorded object and then propagates as an object beam to the holographic plate. The holographic plate is configured to receive the reference beam and the object beam, and generate the holographic interferogram of the recorded object formed after the reference beam and the object beam interfere.

In an embodiment, the holographic plate includes a charge-coupled device.

In an embodiment, the second light source is a laser light source.

DETAILED DESCRIPTION

In order to make those skilled in the art better understand the technical solutions of the present disclosure, a holographic reproduction device, a holographic reproduction system, and a holographic display system provided by the present disclosure are described in detail below with reference to the accompanying drawings.

FIG. 1is a schematic diagram showing a structure of a holographic reproduction device according to an embodiment of the present disclosure, andFIG. 2is a schematic diagram showing a structure of an electrically addressed liquid crystal display panel ofFIG. 1. As shown inFIG. 1andFIG. 2, the holographic reproduction device includes: a first light source1and at least one electrically addressed liquid crystal display panel2(EALCD for short). The first light source1provides first coherent light. The liquid crystal material in the electrically addressed liquid crystal display panel2includes smectic liquid crystal. The at least one electrically addressed liquid crystal display panel2is configured to display a holographic interferogram, so that the first coherent light is diffracted to present a holographic reproduction image.

In some embodiments, the first light source1is a laser light source, since the laser light source has good coherence.

It should be noted that there may be one or more electrically addressed liquid crystal display panels2in the present disclosure.FIG. 1shows only one electrically addressed liquid crystal display panel2, and embodiments in which a plurality of electrically addressed liquid crystal display panels2are provided will be described below.

The principle of the holographic reproduction device provided by the present disclosure is as follows: when holographic reproduction is needed, the electrically addressed liquid crystal display panel2displays a holographic interferogram of a recorded object, the holographic interferogram is irradiated with the first coherent light generated by the first light source1, and the first coherent light transmitting through the holographic interferogram is diffracted to reproduce light wave information of the object beam, thereby realizing holographic reproduction. It should be noted that the detailed principle for implementing holographic reproduction based on the holographic interferogram will be described in detail later.

The principle of displaying a holographic interferogram by the electrically addressed liquid crystal display panel2in the present disclosure will be described below in detail with reference to the accompanying drawings.

The electrically addressed liquid crystal display panel shown inFIGS. 1 and 2is a reflective electrically addressed liquid crystal display panel2, that is, a reflective layer8is provided on a side of the electrically addressed liquid crystal display panel2distal to a viewing side (i.e., people look at images from the viewing side), and a light source is located on the viewing side of the electrically addressed liquid crystal display panel2.

FIG. 3ais a schematic diagram showing the electrically addressed liquid crystal display panel ofFIG. 2in a light transmitting state, andFIG. 3bis a schematic diagram showing the electrically addressed liquid crystal display panel ofFIG. 2in a light scattering state. As shown inFIG. 3aandFIG. 3b, in the present disclosure, the electrically addressed liquid crystal display panel2includes a first substrate3and a second substrate4which are opposite to each other with liquid crystal5disposed therebetween. A gate line (not shown), a data line (not shown) and an array of pixel units are formed on the first substrate3. Each pixel unit includes: a thin film transistor T and a pixel electrode6. A common electrode7is formed on the second substrate4, and an electric field for controlling the deflection of the liquid crystal5may be formed between the pixel electrodes6and the common electrode7.

In the present disclosure, the liquid crystal5in the electrically addressed liquid crystal display panel2is a smectic liquid crystal having a two-dimensional ordered characteristic, that is, the liquid crystal molecules flow in one layer and do not flow between layers. Referring toFIG. 3a, when a first predetermined voltage V0is applied to the pixel electrodes6via data lines, the liquid crystal molecules are in a regular arrangement state, the pixel units are in a light transmitting state (i.e., a bright state), and a corresponding light transmittance is Q0; referring toFIG. 3b, when a second predetermined voltage V1is applied to the pixel electrodes6via the data lines, the liquid crystal molecules5are in a disordered arrangement state, the pixel units are in a light scattering state (i.e., a dark state), and a corresponding light transmittance is Q1. When a voltage in a range from V0to V1is applied to the pixel electrodes6, the pixel units liquid crystal molecules5are in a state between the light transmitting state and the light scattering state, a corresponding light transmittance is between Q0and Q1. In this way, the light intensity can be adjusted to correspond to various display gray scales.

In the present disclosure, magnitudes of the pixel voltages applied to the pixel electrodes6can be independently controlled to independently control the light transmittances of the pixel units, thereby realizing the display of a holographic interferogram. When a beam of coherent light is incident on the electrically addressed liquid crystal display panel2, the pixel units adjust the light to cause fresnel diffraction, that is, the brightnesses of the pixel units of the electrically addressed liquid crystal display panel are controlled to form an interferogram as shown inFIG. 10, so that the light incident onto the electrically addressed liquid crystal display panel2is diffracted to realize the holographic image reproduction.

It should be noted that after a certain voltage is applied to the pixel electrode6to control the light transmittance of the pixel unit corresponding to the pixel electrode6to be a desired value, if the voltage applied to the pixel electrode6is removed (no voltage is applied to the pixel electrode6, and no electric field is formed between the pixel electrode6and the common electrode7), the former state, that is, the steady state, is maintained due to the interaction force between the smectic liquid crystal molecules, and therefore the light transmittance of the pixel unit is maintained at the desired value. Based on the principle, when a static 3D image needs to be reproduced, the corresponding voltages need to be applied to the pixel electrodes6of the electrically addressed liquid crystal display panel2only at the initial moment to control the electrically addressed liquid crystal display panel2to display the holographic interferogram. After a period of time (i.e., after the deflection of the liquid crystal is stable), the voltages on the pixel electrodes6are removed, the electrically addressed liquid crystal display panel2can still maintain displaying the holographic interferogram, that is, the electrically addressed liquid crystal display panel2can still maintain reproduction of the static 3D image, and therefore the technical scheme of the present disclosure can greatly reduce power consumption.

Based on the above characteristics, the holographic reproduction device according to the present disclosure may be used as a structure or device for displaying a static picture, such as a 3D billboard or a 3D electronic label.

With continued reference toFIG. 1, the first coherent light generated by the first light source1is incident onto the electrically addressed liquid crystal display panel2on which the holographic interferogram is displayed to reproduce the light wave information of an object beam, and the light transmitting through the electrically addressed liquid crystal display panel2is reflected toward the human eye by the reflective layer8, so that an image of the recorded object can be observed with human eye.

It should be noted that, in some embodiments, in order to improve the display effect, an optical system9(e.g., a lens) is disposed at a light exit side of the first light source1to expand the light emitted from the first light source1; and an optical system10(e.g., a lens) is disposed on a viewing side of the electrically addressed liquid crystal display panel2to converge the light from the electrically addressed liquid crystal display panel2. It should be understood by those skilled in the art that each of the optical systems9and10is an optional structure in the present disclosure, and does not limit the present disclosure.

FIG. 4is a schematic diagram showing a structure of a holographic reproduction device according to an embodiment of the present disclosure. As shown inFIG. 4, the holographic reproduction device shown inFIG. 4is different from the holographic reproduction device shown inFIG. 1in that the holographic reproduction device shown inFIG. 4further includes: a first transflective structure11and a first reflective structure12. The first transflective structure11and the first reflective structure12are arranged on the viewing side of the electrically addressed liquid crystal display panel2. The first transflective structure11is configured to transmit a portion of the received first coherent light to the first reflective structure12; and the first reflective structure12is configured to reflect the received light to the first transflective structure11. The first transflective structure11is further configured to reflect received light reflected by the first reflective structure12to the electrically addressed liquid crystal display panel2, and further transmit received light reflected by the reflective layer8of the electrically addressed liquid crystal display panel2to an optical system10(e.g., a lens), thereby converging the light into the human eye by the optical system10.

Referring toFIG. 4, a portion of the first coherent light emitted from the first light source1transmits through the first transflective structure11, reaches the first reflective structure12, is reflected by the first reflective structure12, and then reaches the first transflective structure11again. The portion of light is partially reflected by the first transflective structure11and incident onto the electrically addressed liquid crystal display panel2. The light incident onto the electrically addressed liquid crystal display panel2is diffracted when the light passing through a holographic interferogram displayed on the electrically addressed liquid crystal display panel2to reproduce the light wave information of the object beam. The light passing through the holographic interferogram is reflected by the reflective layer8and then incident into human eyes, so that a 3D image of a recorded object can be observed with human eyes.

FIG. 5is a schematic diagram showing a structure of a holographic reproduction device according to an embodiment of the present disclosure. As shown inFIG. 5, the electrically addressed liquid crystal display panel2inFIG. 5is different from the holographic reproduction device shown inFIGS. 1 and 4in that the electrically addressed liquid crystal display panel2inFIG. 5is transmissive LCD panel without reflective layer8in which the first light source1is located on a side of the electrically addressed liquid crystal display panel2distal to the viewing side.

During reproduction, the first coherent light emitted from the first light source1is diffracted when the first coherent light passes through the holographic interferogram displayed on the electrically addressed liquid crystal display panel2to reproduce the light wave information of the object beam, and the light passing through the holographic interferogram is directly incident into the human eyes, so that a 3D image of the recorded object can be observed with human eyes.

FIG. 6is a schematic diagram showing a structure of a holographic reproduction device according to an embodiment of the present disclosure. As shown inFIG. 6, the holographic reproduction device shown inFIG. 6is different from the holographic reproduction device shown inFIG. 5in that the holographic reproduction device shown inFIG. 6has N electrically addressed liquid crystal display panels2, where N≥2. All the electrically addressed liquid crystal display panels2are arranged in sequence. Any two adjacent electrically addressed liquid crystal display panels2are spliced together, and the two electrically addressed liquid crystal display panels2spliced together form a dihedral angle which is larger or equal to 90° and less than 180°.

In the holographic reproduction device shown inFIG. 6, each of the electrically addressed liquid crystal display panels2displays a portion of a holographic interferogram, and images displayed on all the electrically addressed liquid crystal display panels2are spliced together to form the holographic interferogram. It should be noted that the process of displaying a complete image through a plurality of LCD panels2in a splicing manner belongs to the conventional art in the field, and will not be described in detail herein.

It should be noted thatFIG. 6only schematically shows two electrically addressed liquid crystal display panels2. However, the number of the electrically addressed liquid crystal display panels2may be three or more in the present embodiment.

The holographic reproduction device shown inFIG. 6can have an improved viewing angle, which will be described in detail below with reference to the accompanying drawings.

FIG. 7ais a schematic diagram showing a viewing angle of the holographic reproduction device shown inFIG. 5, andFIG. 7bis a schematic diagram showing a viewing angle of the holographic reproduction device shown inFIG. 6. As shown inFIG. 7aandFIG. 7b, assuming that a viewing angle of the holographic reproduction device shown inFIG. 5is a, and a dihedral angle formed by the two electrically addressed liquid crystal display panels2inFIG. 6is (180°−β), where β is an acute angle, and then a viewing angle of the holographic reproduction device shown inFIG. 6is (α+β).

In the embodiment, assuming that a dihedral angle formed by a first electrically addressed liquid crystal display panel2and a second electrically addressed liquid crystal display panel2is (180°−β1), a dihedral angle formed by the second electrically addressed liquid crystal display panel2and a third electrically addressed liquid crystal display panel2is (180°−β2), . . . , and a dihedral angle formed by the (N−1)thelectrically addressed liquid crystal display panel2and the Nthelectrically addressed liquid crystal display panel2is (180°−βN−1), a viewing angle of the holographic reproduction device is

α+∑j=1N-1⁢⁢βj,
where βjis a dihedral angle formed by the jthelectrically addressed liquid crystal display panel2and the (j+1)thelectrically addressed liquid crystal display panel2.

It should be noted that, in practical applications, when a dihedral angle of two adjacent electrically addressed liquid crystal display panels2is designed, it should be ensured that a viewing angle

α+∑j=1N-1⁢⁢βj
of the resulting holographic reproduction device is not larger than 180°.

In practical applications, considering the cost of the device and the range of the viewing angle, in an embodiment, the number of the electrically addressed liquid crystal display panels2is two, and the dihedral angle formed by the two electrically addressed liquid crystal display panels2can be designed and adjusted as needed.

In the holographic reproduction device shown inFIG. 6, an embodiment in which one first light source1is provided on a side of each electrically addressed liquid crystal display panels2distal to the viewing side and the first light sources1are the same light source is merely an optional implementation.

FIG. 8is a schematic diagram showing a structure of a holographic reproduction device according to an embodiment of the present disclosure. As shown inFIG. 8, the holographic reproduction device shown inFIG. 8is different from the holographic reproduction device shown inFIG. 6in that the holographic reproduction device shown inFIG. 8has only one first light source1. Among all the electrically addressed liquid crystal display panels2, a second transflective structure13is located on a side, distal to the viewing side, of each of the electrically addressed liquid crystal display panels2except the last electrically addressed liquid crystal display panels2. A second reflective structure14is located on a side of the last electrically addressed liquid crystal display panel2distal to the viewing side. The first light source1is located on a side of a second transflective structure13corresponding to the first electrically addressed liquid crystal display panel2distal to the viewing side.

The second transflective structure13on a side of the first electrically addressed liquid crystal display panel2distal to the viewing side is configured to transmit a portion of the received first coherent light to the first electrically addressed liquid crystal display panel2, and transmit another portion of the received first coherent light to a second transflective structure13on a side of a second electrically addressed liquid crystal display panel2distal to the viewing side.

A second transflective structure13on a side of the ithelectrically addressed liquid crystal display panel2distal to the viewing side is configured to reflect a portion of the received coherent light to the ithelectrically addressed liquid crystal display panel2, and transmit another portion of the received coherent light to a second transflective structure13or a second reflective structure14(that is, the light passing through a second transflective structure13on a side of the (N−1)thelectrically addressed liquid crystal display panel2distal to the viewing side transmits to a second reflective structure14on a side of the Nthelectrically addressed liquid crystal display panel2distal to the viewing side) on a side of the (i+1)thelectrically addressed liquid crystal display panel2distal to the viewing side, where 1≤i≤N−1, and N is the total number of the electrically addressed liquid crystal display panels.

The second reflective structure14on the side of the Nthelectrically addressed liquid crystal display panel2distal to the viewing side is configured to reflect the received light to the Nthelectrically addressed liquid crystal display panel2.

The holographic reproduction device shown inFIG. 8can have a reduced number of first light sources1as compared to the embodiment shown inFIG. 6.

In order to make the first coherent light propagating to each of the electrically addressed liquid crystal display panels2have the same light intensity, so as to improve the uniformity of display brightness of the holographic reproduction device, in this embodiment, the second transflective structure13on the side of the first electrically addressed liquid crystal display panel2distal to the viewing side has a light transmittance of

1N,
and the second transflective structure13on the side of the ithelectrically addressed liquid crystal display panel2distal to the viewing side has a light transmittance of

In the present disclosure, assuming that the first coherent light emitted from the first light source1has an initial light intensity of S, the first coherent light propagating to each of the electrically addressed liquid crystal display panels2may have a light intensity of

SN
based on the above design.

An embodiment of the present disclosure further provides a holographic reproduction system including the holographic reproduction device according to any one of the foregoing embodiments.

FIG. 9is a schematic diagram showing a structure of a holographic display system according to an embodiment of the present disclosure, andFIG. 10is a schematic diagram showing a holographic interferogram acquired by a holographic plate according to an embodiment of the present disclosure. As shown inFIG. 9andFIG. 10, an embodiment of the present disclosure further provides a holographic display system including a holographic reproduction system in which the holographic reproduction device described in the foregoing embodiment is adopted. The detailed description of the holographic reproduction device may refer to the contents in the foregoing embodiment, and is not given herein again.

In some embodiments, the holographic display system further includes a holographic recording system configured to generate a holographic interferogram of a recorded object and send display data corresponding to the holographic interferogram to the electrically addressed liquid crystal display panel2.

In an embodiment, the holographic recording system includes: a second light source15, a third transflective structure16, a third reflective structure17and a holographic plate18.

The second light source15provides second coherent light. The third transflective structure16reflects a portion of the second coherent light received from the second light source15as a reference beam to the holographic plate18, and transmits another portion of the second coherent light received from the second light source15to the third reflective structure17. The third reflective structure17reflects the light received from the third transflective structure16to the recorded object, and the light incident on the recorded object is reflected by a surface of the recorded object and then propagates to the holographic plate18as an object beam. The holographic plate18receives the reference beam and the object beam, and generates a holographic interferogram of the recorded object formed after the optical interference between the reference beam and the object beam.

In some embodiments, the second light source15is a laser light source, since the laser light source has good coherence.

In some embodiments, the holographic plate18includes a charge-coupled device (CCD for short). The charge-coupled device collects the holographic interferogram of the recorded object formed after the optical interference between the reference beam and the object beam, generates display data corresponding to the holographic interferogram, and sends the display data to the electrically addressed liquid crystal display panel2, so that the electrically addressed liquid crystal display panel2displays the holographic interferogram.

The operation of the holographic display system according to this embodiment includes the following two steps: 1) holographic recording; and 2) holographic reproduction.

The holographic recording is realized by a holographic recording system, and the holographic recording is specifically as follows.

The second coherent light from the second light source15is incident onto the third transflective structure16. A portion of the second coherent light is reflected by the third transflective structure16and then propagates to the holographic plate18as a reference beam, and another portion of the second coherent light transmits through the third transflective structure16to the third reflective structure17. The light incident onto the third reflective structure17is reflected by the third reflective structure17to the recorded object, and the light is then reflected by the surface of the recorded object and propagates to the holographic plate18as an object beam, and the reference beam and the object beam interfere with each other at the holographic plate18.

According to the wave equation of light, assuming that the complex amplitude O(x,y) of the object beam and the complex amplitude R(x,y) of the reference beam at coordinate (x, y) on the holographic plate18are as follows:
O(x,y)=O0(x,y)exp[jϕo(x,y)]
R(x,y)=R0(x,y)exp[jϕo(x,y)],

the object beam and the reference beam interfere at an interference plane, and the interference light field at coordinate (x, y) on the holographic plate18can be expressed as:

By introducing the reference beam, the phase distribution of the object beam is converted into the intensity distribution of the interference fringes. The wavefront recording has a physical significance of converting the intensity and phase information of the object beam into the light intensity distribution through the interference fringes. The light intensity distribution is recorded in a form of a two-dimensional image, and the holographic interferogram recorded by the holographic plate18is shown inFIG. 10.

The holographic plate18records the holographic interferogram to obtain corresponding display data, and transmits the display data to the holographic reproduction system in a form of an electric signal through a signal line, so that the holographic reproduction system can perform holographic reproduction subsequently.

The holographic reproduction is realized by a holographic reproduction system, and the holographic reproduction is specifically as follows.

The electrically addressed liquid crystal display panel2in the holographic reproduction system displays a holographic interferogram according to the received display data (it is possible that only one electrically addressed liquid crystal display panel2displays the holographic interferogram independently, or a plurality of electrically addressed liquid crystal display panels2display the holographic interferogram in a splicing manner), the first coherent light generated by the first light source1is incident on the electrically addressed liquid crystal display panel2displaying the holographic interferogram, and the first coherent light is diffracted when the first coherent light passes through the holographic interferogram to reproduce the light wave information of the object beam, thereby realizing holographic reproduction.

The principle of diffracting the first coherent light when the first coherent light passes through the holographic interferogram to reproduce the light wave information of the object beam is as follows.

As can be seen from the foregoing, the interference light field at coordinate (x, y) on the holographic interferogram is I(x,y). Assuming that the first coherent light currently incident on the holographic interferogram has the following complex amplitude at coordinate (x, y):
C(x,y)=C0(x,y)exp[jϕc(x,y)],

when the first coherent light transmits through the holographic interferogram, the resulting light wave has the following complex amplitude at coordinate (x, y):

where C0O0R0exp[j(ϕo−ϕr+ϕc)] is the light wave information (including light intensity and phase) of the reproduced object beam. Therefore the transmitted light can reproduce a 3D stereoscopic image of the recorded object.

In the present disclosure, since the liquid crystal material in the electrically addressed liquid crystal display panel2is the smectic liquid crystal, during the holographic reproduction process, the corresponding voltages need to be applied to the pixel electrodes6on the electrically addressed liquid crystal display panel2only at the initial time to control the electrically addressed liquid crystal display panel2to display the holographic interferogram. After a period of time (i.e., after the deflection of liquid crystal is stable), the voltages on the pixel electrodes6are removed, the electrically addressed liquid crystal display panel2can still maintain displaying the holographic interferogram, that is, the electrically addressed liquid crystal display panel2can still maintain reproduction of the static 3D image, and therefore the technical scheme of the present disclosure can greatly reduce power consumption.

It should be understood that the above implementations are merely exemplary embodiments for the purpose of illustrating the principles of the present disclosure. However, the present disclosure is not limited thereto. It will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and essence of the present disclosure, which are also to be regarded as falling within the scope of the present disclosure.