阅读说明：本技术 一种多维空-时光场压缩全息加密装置及方法 (Multi-dimensional space-time optical field compression holographic encryption device and method ) 是由 张�成 周家璇 吴峰 韦穗 程鸿 沈川 章权兵 于 2021-06-22 设计创作，主要内容包括：本发明公开了一种多维空-时光场压缩全息加密装置及方法,属于信息安全技术领域,包括扩束光学组件、分束器组、多维空-时光场、空间光调制器和探测器,扩束光学组件布置在激光束照射在原始物体上所产生反射光的路径上,经扩束光学组件扩束准直后的激光束的光路径上布置有第一分束器,第一分束器将激光束分为物光束和参考光束,物光束的路径上设有多维空-时光场,与光场相距为Δz-1的位置布置有空间光调制器,空间光调制器和光场之间布置有第二分束器,与空间光调制器相距为Δz-2的位置布置有探测器；空间光调制器生成的时变复合掩膜由时变随机相位掩膜和时变透镜相位因子组成。本发明可有效的降低解密重建时不同帧之间的串扰影响。(The invention discloses a multi-dimensional space-time light field compression holographic encryption device and method, belonging to the technical field of information security, and comprising a beam expanding optical component, a beam splitter group, a multi-dimensional space-time light field, a spatial light modulator and a detector, wherein the beam expanding optical component is arranged on a path of reflected light generated by irradiating a laser beam on an original object, a first beam splitter is arranged on a light path of the laser beam subjected to beam expanding and collimation by the beam expanding optical component, the laser beam is divided into an object beam and a reference beam by the first beam splitter, the path of the object beam is provided with the multi-dimensional space-time light field, and the distance between the multi-dimensional space-time light field and the light field is delta z 1 Is arranged with a spatial light modulator, a second beam splitter is arranged between the spatial light modulator and the light field, at a distance deltaz from the spatial light modulator 2 A detector is arranged at the position of the probe; the time-varying composite mask generated by the spatial light modulator is composed of a time-varying random phase mask and a time-varying lens phase factor. The invention can effectively reduce decryptionCrosstalk between different frames during reconstruction.)

1. A multi-dimensional space-time light field compression holographic encryption device is characterized by comprising a beam expanding optical assembly, a beam splitter group, a multi-dimensional space-time light field, a spatial light modulator and a detector, wherein the multi-dimensional space-time light field is a 3D space-time light field, a color space-time light field or a 4D space-time light field, and the beam splitter group comprises a first beam splitter and a second beam splitter; the beam expanding optical assembly is arranged atThe laser beam irradiates on the path of reflected light generated on an original object, a first beam splitter is arranged on the light path of the laser beam after beam expansion and collimation by a beam expansion optical assembly, the laser beam is divided into an object beam and a reference beam by the first beam splitter, a multi-dimensional space-time light field is arranged on the path of the object beam, and the distance between the multi-dimensional space-time light field and the light field is delta z₁Is arranged with a spatial light modulator, a second beam splitter is arranged between the spatial light modulator and the light field, at a distance deltaz from the spatial light modulator₂A detector is arranged at the position of the probe; the time-varying composite mask generated by the spatial light modulator is composed of a time-varying random phase mask and a time-varying lens phase factor.

2. The multi-dimensional space-time optical field compression holographic encryption device of claim 1, wherein when the multi-dimensional space-time optical field is a 3D space-time optical field or a 4D space-time optical field, the beam expanding optical assembly comprises a beam expander and a lens, the beam expander is disposed on a path of reflected light generated by the laser beam irradiating on the original object, the lens is disposed on a light path of the laser beam after beam expanding and collimating by the beam expander, and the first beam splitter is disposed on a transmission light path of the lens.

3. The multi-dimensional space-time optical field compression holographic encryption device of claim 1, wherein when the multi-dimensional space-time optical field is a color space-time optical field, the beam expanding optical assembly comprises a first beam expander, a second beam expander, a third beam expander, a first lens, a second lens, a third beam splitter and a fourth beam splitter, the first beam expander and the first lens are sequentially arranged on a red laser beam path, the second beam expander and the second lens are sequentially arranged on a green laser beam path, the third beam expander and the third lens are sequentially arranged on a blue laser beam path, the third beam splitter is arranged on a transmission optical path of the first lens and the second lens, and the fourth beam splitter is arranged at a position where an optical path split by the third beam splitter intersects a transmission optical path of the third lens.

4. The multi-dimensional space-time optical field compression holographic encryption device of claim 1, whichCharacterized in that the time-varying composite maskWherein the time-varying random phase mask isThe phase factor of the time-varying lens is exp (j.2 pi d (x, y, t)); wherein the content of the first and second substances,the matrix is a random matrix which is uniformly distributed within 0-1 of time variation, d (x, y, t) is a propagation kernel of time variation, exp () is an exponential function with a natural constant e as a base, and j is an imaginary unit.

5. A multi-dimensional space-time optical field compression holographic encryption method for controlling the encryption apparatus of any one of claims 1-4, comprising:

the first beam splitter divides the laser beam after beam expansion and collimation of the beam expansion optical assembly into an object beam and a reference beam;

the object beam irradiates on the multi-dimensional space-time light field and is transmitted to the spatial light modulator, and the multi-dimensional space-time light field is encrypted through a time-varying composite mask generated by the spatial light modulator and then is adjusted to be parallel to the reference beam through the second beam splitter;

and transmitting the encrypted and adjusted object beam and reference beam to the plane of the detector for superposition recording to obtain the hologram.

6. The method of claim 5, wherein when the multidimensional space-time light field is a 3D space-time light field, the representation of the hologram is in the form of:

wherein, A and E_lAre respectively provided withAnd L represents the total frame number of the 3D space-time light field for the reference light field and the object light field of the L frame space-time light field to be transmitted to the detector plane.

7. The method of claim 5, wherein when the multi-dimensional space-time light field is a color space-time light field, the representation of the hologram is in the form of:

wherein A is_cAnd E_l,cC channels, n, of reference and object fields respectively, the first frame of color space-time light field propagating to the detector plane_l,cRepresenting the noise when the L frame space-time light field c channel is recorded, and L represents the total frame number of the color space-time light field.

8. The method of multi-dimensional space-time light field compression holographic encryption of claim 5, wherein when the multi-dimensional space-time light field is a 4D space-time light field, the hologram representation is represented in the form of:

wherein, A and E_4d,lThe reference light field and the object light field are respectively transmitted to the detector plane by the L frame space-time light field, and L represents the total frame number of the 4D space-time light field.

9. A multi-dimensional space-time light field compression holographic decryption method is characterized in that the method is used for reconstructing an original light field by adopting a TwinST algorithm on an encrypted hologram, a propagation distance and a time-varying composite mask obtained by the encryption method of any one of claims 5 to 8.

Technical Field

The invention relates to the technical field of information security, in particular to a multi-dimensional space-time optical field compression holographic encryption device and method.

Background

With the continuous development of science and technology, the application of the information security field is more and more extensive, and the complexity of the encryption scene is improved. Especially, scenes recorded in some complex occasions not only include time dimension, but also have depth information, such as image transmission in the military field, water quality monitoring by utilizing a holographic microscope, microorganism monitoring in water and the like. Optical encryption has received increasing attention as a very effective solution to the problem of information security. However, as the optical field time dimension increases, the huge amount of data, the time required for encryption and decryption, and the crosstalk between different frames become major factors limiting the development of space-time optical field encryption technology.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and reduce the crosstalk influence among different frames.

In order to achieve the above objects, in one aspect, the present invention provides a multi-dimensional space-time optical field compression holographic encryption apparatus, including a beam-expanding optical component, a beam splitter group, a multi-dimensional space-time optical field, a spatial light modulator and a detector, where the multi-dimensional space-time optical field is a 3D space-time optical field, a color space-time optical field or a 4D space-time optical field, and the beam splitter group includes a first beam splitter and a second beam splitter; the beam expanding optical assembly is arranged on a path of reflected light generated by irradiating a laser beam on an original object, a first beam splitter is arranged on a light path of the laser beam after beam expanding and collimating by the beam expanding optical assembly, the laser beam is divided into an object beam and a reference beam by the first beam splitter, a multi-dimensional space-time light field is arranged on the path of the object beam, and the distance between the multi-dimensional space-time light field and the light field is delta z₁Is arranged with a spatial light modulator, a second beam splitter is arranged between the spatial light modulator and the light field, at a distance deltaz from the spatial light modulator₂A detector is arranged at the position of the probe; the time-varying composite mask generated by the spatial light modulator is composed of a time-varying random phase mask and a time-varying lens phase factor.

Further, when the multi-dimensional space-time light field is a 3D space-time light field or a 4D space-time light field, the beam expanding optical assembly includes a beam expander and a lens, the beam expander is arranged on a path of reflected light generated by the laser beam irradiating on the original object, the lens is arranged on a light path of the laser beam after beam expanding and collimating by the beam expander, and the first beam splitter is arranged on a transmission light path of the lens.

Further, when the multi-dimensional space-time light field is a color space-time light field, the beam expanding optical assembly comprises a first beam expander, a second beam expander, a third beam expander, a first lens, a second lens, a third beam splitter and a fourth beam splitter, the first beam expander and the first lens are sequentially arranged on a red laser beam path, the second beam expander and the second lens are sequentially arranged on a green laser beam path, the third beam expander and the third lens are sequentially arranged on a blue laser beam path, the third beam splitter is arranged on transmission light paths of the first lens and the second lens, and the fourth beam splitter is arranged at a position where a light path split by the third beam splitter intersects with a transmission light path of the third lens.

Further, the time-varying composite maskWherein the time-varying random phase mask isThe phase factor of the time-varying lens is exp (j.2 pi d (x, y, t)); wherein the content of the first and second substances,the matrix is a random matrix which is uniformly distributed within 0-1 of time variation, d (x, y, t) is a propagation kernel of time variation, exp () is an exponential function with a natural constant e as a base, and j is an imaginary unit.

In another aspect, a multi-dimensional space-time optical field compression holographic encryption method is used for controlling the encryption device, and includes:

the first beam splitter divides the laser beam after beam expansion and collimation of the beam expansion optical assembly into an object beam and a reference beam;

the object beam irradiates on the multi-dimensional space-time light field and is transmitted to the spatial light modulator, and the multi-dimensional space-time light field is encrypted through a time-varying composite mask generated by the spatial light modulator and then is adjusted to be parallel to the reference beam through the second beam splitter;

and transmitting the encrypted and adjusted object beam and reference beam to the plane of the detector for superposition recording to obtain the hologram.

Further, when the multi-dimensional space-time light field is a 3D space-time light field, the representation of the hologram is:

wherein, A and E_lThe L is a reference light field and an object light field which are respectively transmitted to the detector plane by the L frame space-time light field, and L represents the total frame number of the 3D space-time light field.

Further, when the multi-dimensional space-time light field is a color space-time light field, the representation form of the hologram is:

wherein A is_cAnd E_l,cC channels, n, of reference and object fields respectively, the first frame of color space-time light field propagating to the detector plane_l,cRepresenting the noise when the L frame space-time light field c channel is recorded, and L represents the total frame number of the color space-time light field.

Further, when the multi-dimensional space-time light field is a 4D space-time light field, the hologram is represented in the form of:

wherein, A and E_4d,lThe reference light field and the object light field are respectively transmitted to the detector plane by the L frame space-time light field, and L represents the total frame number of the 4D space-time light field.

On the other hand, the method for compressing and holographically decrypting the multidimensional space-time light field is used for reconstructing an original light field by adopting a TWIST algorithm based on the encrypted hologram, the propagation distance and the time-varying composite mask obtained by the encryption method.

Compared with the prior art, the invention has the following technical effects: the invention realizes the light field encryption by the composite phase mask which is generated by the spatial light modulator and consists of the random phase mask and the lens phase factor during encryption, and modulates different frames of images of the light field to different spaces by utilizing the lens phase factor, thereby effectively reducing the crosstalk influence between different frames during decryption reconstruction.

Drawings

The following detailed description of embodiments of the invention refers to the accompanying drawings in which:

FIG. 1 is a block diagram of a 3D space-time optical field compression holographic encryption apparatus;

FIG. 2 is a schematic diagram of 3D space-time optical field compression holographic encryption and decryption;

FIG. 3 is a block diagram of a color space-time optical field compression holographic encryption apparatus;

FIG. 4 is a schematic diagram of color space-time optical field compression holographic encryption and decryption;

FIG. 5 is a schematic diagram of a 4D space-time optical field compression holographic encryption;

FIG. 6 is a flow chart of a multi-dimensional space-time optical field compression holographic encryption method.

Detailed Description

To further illustrate the features of the present invention, refer to the following detailed description of the invention and the accompanying drawings. The drawings are for reference and illustration purposes only and are not intended to limit the scope of the present disclosure.

As shown in fig. 1 to 5, this embodiment discloses a multi-dimensional space-time optical field compression holographic encryption apparatus, which includes a beam expanding optical assembly, a beam splitter group, a multi-dimensional space-time optical field, a spatial light modulator, and a probeThe multi-dimensional space-time light field is a 3D space-time light field, a color space-time light field or a 4D space-time light field, and the beam splitter group comprises a first beam splitter and a second beam splitter; the beam expanding optical assembly is arranged on a path of reflected light generated by irradiating a laser beam on an original object, a first beam splitter is arranged on a light path of the laser beam after beam expanding and collimating by the beam expanding optical assembly, the laser beam is divided into an object beam and a reference beam by the first beam splitter, a multi-dimensional space-time light field is arranged on the path of the object beam, and the distance between the multi-dimensional space-time light field and the light field is delta z₁Is arranged with a spatial light modulator, a second beam splitter is arranged between the spatial light modulator and the light field, at a distance deltaz from the spatial light modulator₂A detector is arranged at the position of the probe; the time-varying composite mask generated by the spatial light modulator is composed of a time-varying random phase mask and a time-varying lens phase factor.

Specifically, as shown in fig. 1 to 2, when the multidimensional space-time light field is a 3D space-time light field or a 4D space-time light field, the beam expanding optical assembly includes a beam expander and a lens, the beam expander is arranged on a path of reflected light generated by a laser beam irradiating on the original object, the lens is arranged on a path of the laser beam expanded and collimated by the beam expander, and the first beam splitter is arranged on a transmission light path of the lens.

As shown in fig. 3 to 4, when the multi-dimensional space-time light field is a color space-time light field, the beam expanding optical assembly includes a first beam expander, a second beam expander, a third beam expander, a first lens, a second lens, a third beam splitter, and a fourth beam splitter, the first beam expander and the first lens are sequentially disposed on a red laser beam path, the second beam expander and the second lens are sequentially disposed on a green laser beam path, the third beam expander and the third lens are sequentially disposed on a blue laser beam path, the third beam splitter is disposed on a transmission light path of the first lens and the second lens, and the fourth beam splitter is disposed at a position where a light path split by the third beam splitter intersects with a transmission light path of the third lens.

As a further preferred technical solution, the time-varying composite maskWherein the time-varying random phase mask isThe time varying lens phase factor is exp (j · 2 π d (x, y, t)).

Wherein the content of the first and second substances,the matrix is a random matrix which is uniformly distributed within 0-1 of time variation, d (x, y, t) is a propagation kernel of time variation, exp () is an exponential function with a natural constant e as a base, and j is an imaginary unit.

As shown in fig. 1, the 3D space-time optical field compression holographic encryption process is: firstly, a first beam splitter is utilized to divide a laser beam after beam expansion and collimation into object light and reference light, the object light firstly irradiates on a 3D space-time light field with the scattering intensity of O (x, y, t), and then the object light is transmitted to a space delta z away from the light field₁The spatial light modulator plane is modulated by a time-varying mask M (x, y, t), and then the light path is adjusted by a second beam splitter to be parallel to the reference light, and then the light path is propagated by delta z₂The Gabor hologram recorded at a distance to the detector plane can be expressed as the integral of the detector plane optical field intensity I (x, y, t):

wherein: q_[·]Denotes the propagation distance [. cndot.)]The PSF of (2):

since the time-varying mask is transformed in a discrete form, if the Δ t time has L frames of spatial-temporal light fields, the time-varying mask is changed L times at a frequency τ ═ Δ t/L. If the sampling interval is Δ_kAccording to paraxial approximation theory, equation (1) can be discretized as:

wherein: a and E_lA reference light field and an object light field which are respectively transmitted to the detector plane by the first frame space-time light field, k is a wave number,m (x, y, l) is the first frame space-time light field composite phase mask, O (x, y, l) is the scattering density of the first frame space-time light field,is a two-dimensional Fourier transform, j is an imaginary unit, λ is a wavelength,for a length Δ z from the plane of the spatial light modulator to the plane of the detector₂Propagation distance of, n₁，n₂Number of sampling points, Δ, in x, y axes, respectively_kIs the sampling interval.

A single frame hologram acquired by a detector can be written as: i ═ A + E-²＝A²+E²+A^*E+AE^*The reference light a is a constant, and assuming that the reference light intensity is 1, the single-frame hologram can be written as:

wherein A is^*Is the conjugate of A and is a conjugate of A,is E_lIs conjugated to n_lIs the noise of the l-th frame.

FIG. 2 shows a schematic diagram of 3D space-time light field compression holographic encryption, in which parallel light beams are irradiated to O (x, y, t) space-time light field discretized into L frames and then have a distance Δ z₁Is transmitted to the mask plane, and is encoded by a time-varying composite mask consisting of a random phase mask and a variable lens phase, and then is transmitted by delta z₂The distance to the detector plane only requires a single exposure to record the encrypted hologram. Upon reconstruction, combining the resulting encryptionsThe hologram, the propagation distance and the time-varying composite mask can reconstruct an original 3D space-time light field by using a TwinT algorithm, and the method specifically comprises the following steps:

the recording process of the hologram in the delta t time can be modeled as a compressed sensing process, and { vec [ I ] is defined_l(m₁Δ_k,m₂Δ_k)]}^T＝g_l，{vec[O(n₁Δ_k,n₂Δ_k,l)]}^T＝f_lEquation (3) can be simplified as:

wherein:and representing a sensing matrix corresponding to the space-time optical field of the l frame, wherein n is noise. Formula (5) can be written as:

g＝Hf+n (6)

wherein:for the forward imaging model in the time at,

H＝[H₁ H₂ … H_L] (7)

wherein: diag (·) denotes a diagonal matrix.

The estimated value of the original 3D space-time light field can be obtained by solving an unconstrained optimization problem:

as shown in fig. 3, the experimental apparatus for compressing and holographically encrypting a color space-time light field includes, first, parallelly transmitting red, green and blue laser beams to form a composite light beam by combining a space division multiplexing technique, dividing the composite light beam into an object light beam and a reference light beam by using a beam splitter, irradiating the object light beam on the color space-time light field, transmitting the object light beam to a spatial light modulator plane, modulating the object light beam by a time-varying composite phase mask formed by a random phase mask and a lens phase factor, adjusting a light path by the beam splitter to be parallel to the reference light beam, and transmitting the object light beam to a detector plane for recording.

As shown in FIG. 4, the hologram recorded by the detector plane can be expressed as the intensity of the optical field I within Δ t time_rgbIntegration of (x, y, t):

wherein: c belongs to { R, G, B }, and is respectively red, green and blue. O is_c(x, y, t) is the c-channel, Q, of the color space-time light field_[·],cPoint spread functions for different wavelengths of light, M_c(x, y, t) is a time-varying composite phase mask, consisting of a time-varying random phase maskPhase mask exp (j.2 pi d) of time-varying lens_c(x, y, t)).

Wherein: r (x, y, t) is a random phase mask which varies with time.

According to paraxial approximation theory, equation (10) can be discretized as:

wherein: a. the_cAnd E_l,cThe c channels of the reference light field and the object light field which are respectively transmitted to the detector plane by the l frame color space-time light field.

Definition { vec [ I ]_c(m₁Δ_k,m₂Δ_k,l)]}^T＝g_l,c，vec{O_c[n₁Δ_k,n₂Δ_k,l]}＝f_l,cEquation (12) can be simplified as:

wherein:

single-channel holographic recording can be represented as:

g_c＝H_cf_c+n_c (14)

wherein:H_c＝[H_1,c H_2,c … H_L,c]is a sensing matrix corresponding to a c channel of a color space-time light field,is the noise of the c channel of the color hologram.

According to the light three primary color principle, the color hologram obtained by encryption can be written as:

g_rgb＝[g_R,g_G,g_B] (15)

RGB sub-channel reconstruction is carried out at a receiving end during decryption, and estimation values of different channels of an original color space-time optical field are obtained by solving an unconstrained optimization problem respectively:

and finally, fusing estimated values of three channels of RGB, and reconstructing a color space-time light field:

as shown in FIG. 5, the 4D space-time optical field O (x, y, z, t) propagates in the positive z-axis direction by Δ z₁Encrypting the spatial light modulator plane by a time-varying composite phase mask M (x, y, t), and continuously transmitting the delta z₂The hologram is recorded to the detector plane.

The encrypted hologram recorded at the detector plane can be represented as field strength I_4dIntegration of (x, y, t)

Wherein: e₀(x,y,t；z₀) For propagation of the 4D space-time light field to be encrypted to the last layer of plane z₀A light field of (a).

Wherein: q_nThe point spread function of the 4D space-time optical field axial direction from the nth layer to the last layer plane is obtained, the propagation distance is (N-1) deltaz, and N is the number of 4D space-time optical field axial layers.

If the 4D space-time optical field has L frames in Δ t time, the time-varying mask is varied L times at a frequency τ ═ Δ t/L. According to paraxial approximation theory, equation (18) can be discretized as:

in combination with formula (4), the following are obtained:

the recording process of the encrypted hologram in the delta t time can be modeled as a compressed sensing process, and { vec [ I ] is defined_4d(m₁Δ_k,m₂Δ_k,l)]}^T＝g_4d,l，vec{O[n₁Δ_k,n₂Δ_k,z₀-(n-1)·Δz,l]}＝f_n,lEquation (20) can be simplified as:

wherein: sensing matrix of 4D space-time light field of No. l framef_l＝[f_1,l f_2,l … f_N,l]^T，Q＝[Q₁ Q₂ … Q_N]，Q_nAnd the point spread function of the 4D optical field axial direction propagating to the plane of the last layer from the nth layer is expressed, and N belongs to 1-N.

Wherein: b is a block diagonal matrix.

g_4d＝Hf_4d+n (25)

Wherein:H＝[H₁ H₂ … H_L]is the sensing matrix over at time.

The decrypted reconstruction of the 4D space-time light field can be solved by an unconstrained optimization problem:

as shown in fig. 6, the present embodiment discloses a multi-dimensional space-time optical field compression holographic encryption method, which is characterized in that the encryption apparatus used in the above embodiments performs control, and includes the following steps S1 to S3:

s1, dividing the laser beam after beam expansion and collimation by the beam expansion optical assembly into an object beam and a reference beam by the first beam splitter;

s2, irradiating the multi-dimensional space-time light field by an object beam, transmitting the object beam to the spatial light modulator, encrypting the multi-dimensional space-time light field by a time-varying composite mask generated by the spatial light modulator, and adjusting a light path to be parallel to the reference beam by the second beam splitter;

and S3, transmitting the encrypted and adjusted object beam and the reference beam to the plane of the detector for superposition recording to obtain the hologram.

As a further preferred technical solution, when the multidimensional space-time light field is a 3D space-time light field, the representation form of the hologram is:

wherein, A and E_lThe L is a reference light field and an object light field which are respectively transmitted to the detector plane by the L frame space-time light field, and L represents the total frame number of the 3D space-time light field.

As a further preferred technical solution, when the multi-dimensional space-time light field is a color space-time light field, the representation form of the hologram is:

wherein A is_cAnd E_l,cC channels, n, of reference and object fields respectively, the first frame of color space-time light field propagating to the detector plane_l,cRepresenting the noise when the L frame space-time light field c channel is recorded, and L represents the total frame number of the color space-time light field.

As a further preferred technical solution, when the multi-dimensional space-time light field is a 4D space-time light field, the hologram is represented in the form of:

wherein, A and E_4d,lThe reference light field and the object light field are respectively transmitted to the detector plane by the L frame space-time light field, and L represents the total frame number of the 4D space-time light field.

The embodiment also discloses a multi-dimensional space-time light field compression holographic decryption method, which is used for reconstructing an original light field by adopting a TwinT algorithm on the encrypted hologram, the propagation distance and the time-varying composite mask obtained by the encryption method in the embodiment.

The invention realizes the light field encryption by the composite phase mask which is generated by the spatial light modulator and consists of the random phase mask and the lens phase factor during encryption, because the space-time light fields are all superposed to the same encrypted hologram, serious crosstalk influence exists between different layers, and different frame images of the light field are modulated to different spaces by the lens phase factor, thereby effectively reducing the crosstalk influence between different frames during decryption reconstruction. Experiments prove that the multidimensional space-time light field encryption algorithm provided by the invention has low decryption distortion degree and a safe key system, and can decrypt and reconstruct the original space-time light field with high precision only when the encrypted hologram and the complete key system are obtained; the method has good anti-interference capability, the decryption reconstruction performance is slowly descended when the interference noise is gradually enhanced, and the effective information of the original light field can still be obtained.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.