Optical imaging module, array imaging module, floating display apparatus, and multi-layer display device

Abstract

An optical imaging module (100), an array imaging module (900), a floating display apparatus (1800), and a multi-layer display device (1900). The optical imaging module (100) comprises: a light deflection group, at least comprising a first light deflection unit (101) and a second light deflection unit (102) arranged parallel to each other, wherein the light deflection group only modulates light in a first direction; and a first conjugate imaging element (103) located, on an optical path, between the first light deflection unit (101) and the second light deflection unit (102), the optical path length between the first conjugate imaging element (103) and the first light deflection unit (101) being substantially equal to the optical path length between the first conjugate imaging element (103) and the second light deflection unit (102), wherein the optical imaging module (100) is configured to make light beams from points on an object plane (10) converge on a first image plane (20) in a first direction.

Description

Optical imaging module, array imaging module, suspended display device and multi-layer display device Technical Field

[0001] The embodiments described herein generally relate to light field three-dimensional display technology, and more specifically to an optical imaging module, an array imaging module, a suspended display device, and a multi-layer display apparatus for suspended display. Background Art

[0002] Among the many display technologies, air-suspended display technology has attracted the attention of many researchers because it can present images in the air, bringing strong visual impact and a sensory experience that is both real and fake to viewers.

[0003] Existing floating display technology has proposed using a diffuser screen to expand the divergence angle in the vertical viewing direction. This solution is characterized by a wide viewing angle range. However, its disadvantage is that the light emitted by the display module converges on two different planes in the horizontal and vertical directions, and is far apart, resulting in poor image quality and the inability to achieve a large spatial depth display. Furthermore, the floating image formed by this floating display technology solution only has horizontal parallax, not vertical parallax. The vertical spatial position of the floating image is not fixed and moves with the observer's vertical position, affecting some scenarios that require precise interaction. In addition, the required size of the floating image varies depending on the scenario requirements. In the prior art, although various floating display technologies exist, the size of the floating image displayed by the floating display device is generally fixed during the manufacturer's design phase and cannot be adjusted during use. As a result, when users desire floating images of different sizes based on different application scenarios, they usually need to purchase floating display devices of different sizes. Manufacturers of floating display devices need to design different floating display devices (especially different optical systems to adapt to image display units of different sizes) according to different user needs, and adapt them one by one, which consumes a lot of manpower and material resources. Summary of the Invention

[0004] The exemplary embodiments of the present invention aim to overcome the above-mentioned and / or other problems in the prior art, and in particular to provide an optical imaging module, which comprises: a deflection light group, comprising at least a first light deflection unit and a second light deflection unit arranged parallel to each other, wherein the deflection light group modulates light only in a first direction; and a first conjugate imaging element, which is located between the first light deflection unit and the second light deflection unit on the optical path, wherein the optical path between the first conjugate imaging element and the first light deflection unit is substantially equal to the optical path between the first conjugate imaging element and the second light deflection unit, wherein the optical imaging module is configured to cause a light beam from a point on an object plane to converge on a first image plane in the first direction.

[0005] Optionally, the first light deflecting unit is an aperture stop of the optical imaging module in the first direction.

[0006] Optionally, the first light deflecting unit and the second light deflecting unit are configured so that the image height of the optical imaging module in the first direction is equal to the object height in the first direction.

[0007] Optionally, the first light deflecting unit and the second light deflecting unit are the same lens.

[0008] Optionally, the first light deflecting unit is a lens, and its f# is greater than or equal to 1.5 and less than or equal to 6.

[0009] Optionally, the aperture of the light deflecting unit is D, and the distance between the second light deflecting unit and the first light deflecting unit is greater than or equal to 2D.

[0010] Optionally, along the optical path, a distance between the first conjugate imaging element and the first light deflecting unit is less than or equal to a focal length of the first light deflecting unit.

[0011] Optionally, the first conjugate imaging element is a one-dimensional conjugate imaging element, and the first light deflection unit, the second light deflection unit and the first conjugate imaging element cooperate to make the light beam from the point on the object plane converge on the first image plane in the first direction.

[0012] Optionally, the optical imaging module also includes a second conjugate imaging element, which is used to make the light beam from the point on the object plane converge in a second direction on a second image plane different from the first image plane, and the first direction and the second direction are respectively orthogonal to the main optical axis of the optical imaging module.

[0013] Optionally, the first conjugate imaging element and the second conjugate imaging element are one-dimensional reflective retroreflectors, wherein the microstructure units of the first conjugate imaging element and the microstructure units of the second conjugate imaging element are orthogonally arranged.

[0014] Optionally, the first conjugate imaging element and the second conjugate imaging element are arranged relatively parallel, and the optical axes of the first conjugate imaging element and the second conjugate imaging element are perpendicular to the optical axes of the first light deflecting unit and the second light deflecting unit.

[0015] Optionally, the optical imaging module also includes a spectroscopic element, and the light beam from the object plane is deflected by the first light deflection unit and then enters the spectroscopic element, and then is reflected by the spectroscopic element and then enters the first conjugate imaging element, and then is reflected by the first conjugate imaging element and then is transmitted through the spectroscopic element and then enters the second conjugate imaging element, and then is reflected by the second conjugate imaging element and then is reflected by the spectroscopic element and then enters the second light deflection unit, and then is deflected by the second light deflection unit and then propagates toward the first image plane and the second image plane.

[0016] Optionally, the beam splitter element is obliquely disposed between the first conjugate imaging element and the second conjugate imaging element and between the first light deflecting unit and the second light deflecting unit.

[0017] Optionally, the beam splitter element includes: a polarization beam splitter; a first phase delay film, disposed between the first conjugate imaging element and the polarization beam splitter; and a second phase delay film, disposed between the second conjugate imaging element and the polarization beam splitter.

[0018] Optionally, the first conjugate imaging element is a two-dimensional conjugate imaging element, and the first light deflection unit, the second light deflection unit and the first conjugate imaging element cooperate to make the light beam from the point on the object plane converge on the first image plane in the first direction, and the first conjugate imaging element is used to make the light beam from the point on the object plane converge on the first image plane in the second direction, and the first direction and the second direction are respectively orthogonal to the main optical axis of the optical imaging module.

[0019] Optionally, the first conjugate imaging element is a two-dimensional reflective retroreflector, and the optical imaging module also includes a spectrometer and a reflector. The light beam from the object plane is deflected by the first light deflection unit and then enters the spectrometer. It is reflected by the spectrometer to the reflector. After being reflected by the reflector, it is transmitted through the spectrometer to enter the first conjugate imaging element. After being reflected by the first conjugate imaging element, it is reflected by the spectrometer and then enters the second light deflection unit. After being deflected by the second light deflection unit, it propagates toward the first image plane.

[0020] Optionally, the spectroscopic element is obliquely arranged between the reflector and the first conjugate imaging element and between the first light deflection unit and the second light deflection unit, and the optical axes of the reflector and the first conjugate imaging element are perpendicular to the optical axes of the first light deflection unit and the second light deflection unit.

[0021] Optionally, the beam splitter element includes: a polarization beam splitter; a first phase delay film, arranged between the reflector and the polarization beam splitter; and a second phase delay film, arranged between the first conjugate imaging element and the polarization beam splitter.

[0022] Optionally, the first conjugate imaging element is a two-dimensional transmissive retroreflector, and the optical imaging module further includes a reflector. The light beam from the object plane is deflected by the first light deflection unit and then enters the two-dimensional transmissive retroreflector. It is transmitted to the reflector through the two-dimensional transmissive retroreflector, reflected by the reflector, and then reflected by the two-dimensional transmissive retroreflector before entering the second light deflection unit. It is deflected by the second light deflection unit and then propagates toward the first image plane.

[0023] Optionally, the first conjugate imaging element is a one-dimensional transmissive retroreflector, and the second conjugate imaging element is a one-dimensional reflective retroreflector, wherein the first conjugate imaging element is obliquely arranged between the first light deflection unit and the second light deflection unit, and the optical axis of the second conjugate imaging element is perpendicular to the optical axes of the first light deflection unit and the second light deflection unit.

[0024] Optionally, the optical imaging module further includes: a reflective polarizing film, arranged between the first conjugate imaging element and the second light deflection unit and between the first conjugate imaging element and the second conjugate imaging element; and a phase delay film, arranged between the reflective polarizing film and the second conjugate imaging element, wherein the light beam from the object plane is deflected by the first light deflection unit and then enters the one-dimensional transmissive retroreflector, is transmitted to the one-dimensional reflective retroreflector through the one-dimensional transmissive retroreflector, is reflected by the one-dimensional reflective retroreflector, and then is reflected by the reflective polarizing film and then enters the second light deflection unit, and is deflected by the second light deflection unit and propagates toward the first image plane and the second image plane.

[0025] The present invention further provides an array imaging module, comprising: a plurality of optical imaging modules as described above, arranged in an array along the first direction.

[0026] Optionally, the distance between the first light deflecting units of adjacent optical imaging modules is smaller than a preset threshold.

[0027] Optionally, adjacent optical imaging modules have common optical elements.

[0028] Optionally, the array imaging module further includes a grating plate disposed between the optical imaging module and the image plane, wherein the grating plate has light-shielding strips with equal spacing.

[0029] Optionally, the spaces between the elements in the optical imaging module are filled with a medium, and the refractive index of the medium is greater than 1.

[0030] The present invention also provides a suspended display device, comprising: a display module configured to emit display light constituting a target image; and an array imaging module as described above; wherein the display light emitted from the display module passes through the array imaging module to form a suspended image at the first image plane and / or the second image plane.

[0031] Optionally, the display module is a three-dimensional display.

[0032] The present invention also provides a multi-layer display device, comprising: the suspended display device as described above; and a transparent display device, arranged optically downstream of the suspended display device, wherein the display surface of the transparent display device and the suspended image are located at different positions.

[0033] Optionally, the transparent display device includes a transparent display or is implemented by projecting an image onto a transparent film. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The present invention may be better understood by describing exemplary embodiments of the present invention in conjunction with the accompanying drawings, in which:

[0035] 1A and 1B are schematic diagrams showing light propagation of an optical imaging module according to an exemplary embodiment of the present invention.

[0036] FIG2A is a schematic diagram showing the semi-aperture, focal length and image height of the first light deflecting unit.

[0037] FIG. 2B is a schematic diagram showing an optical imaging module including a folded structure.

[0038] 3-4 are schematic diagrams showing light propagation of an optical imaging module according to another exemplary embodiment of the present invention.

[0039] 5A and 5B illustrate examples of two-dimensional reflective retroreflectors.

[0040] FIG. 6 shows an example of a two-dimensional transmissive retroreflector.

[0041] FIG. 7 shows an example of a one-dimensional reflective retroreflector.

[0042] FIG8 shows an example of a one-dimensional transmissive retroreflector.

[0043] FIG9 is a schematic diagram showing an array imaging module according to a first example of the present invention.

[0044] FIG10 is a schematic diagram showing an array imaging module using polarization splitting.

[0045] FIG11 is a schematic diagram showing an array imaging module according to a second example of the present invention.

[0046] FIG12 is a schematic diagram showing an array imaging module using polarization splitting.

[0047] FIG13A is a schematic diagram showing the optical path of an object point formed by stitching images through multiple optical imaging modules.

[0048] FIG13B is a schematic diagram showing the optical paths of different object points passing through a single optical imaging module in the array imaging module.

[0049] FIG14 is a schematic diagram showing an array imaging module according to a third example of the present invention.

[0050] FIG. 15A is a schematic diagram showing an optical imaging module according to a fourth example of the present invention.

[0051] FIG15B is a schematic diagram showing light propagation of an optical imaging module according to a fourth example of the present invention.

[0052] FIG16 is a schematic diagram showing an array imaging module according to a fifth example of the present invention.

[0053] FIG17A is a schematic diagram showing an array imaging module including a grating plate.

[0054] FIG17B shows a schematic diagram of a grating plate.

[0055] FIG18 shows a schematic block diagram of a floating display device according to an embodiment of the present invention.

[0056] FIG. 19 is a schematic diagram illustrating a multi-layer display device according to an embodiment of the present invention.

[0057] FIG20 is a schematic diagram showing a transparent display device implemented by micro-projection;

[0058] FIG21 is a schematic diagram showing a multi-layer display device implementing naked-eye 3D display; and

[0059] 22A-22C are explanatory schematic diagrams showing a display module employing a three-dimensional display. DETAILED DESCRIPTION

[0060] The specific embodiments of the present invention will be described below. It should be noted that in the specific description of these embodiments, in order to provide a concise description, this specification cannot provide a detailed description of all the features of the actual embodiments. It should be understood that in the actual implementation of any embodiment, just as in the process of any engineering project or design project, in order to achieve the specific goals of the developer and to meet system-related or business-related restrictions, various specific decisions are often made, and this will also change from one embodiment to another. In addition, it can also be understood that although the efforts made in this development process may be complex and lengthy, for ordinary technicians in the field related to the content disclosed by the present invention, some design, manufacturing or production changes based on the technical content disclosed in this disclosure are just conventional technical means and should not be understood as the content of this disclosure being insufficient.

[0061] Unless otherwise defined, the technical or scientific terms used in the claims and description shall have the ordinary meaning understood by persons of ordinary skill in the technical field to which the invention belongs. The words "first", "second" and similar terms used in the description and claims of the patent application of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "a" or "an" do not indicate a quantitative limitation, but rather indicate the presence of at least one. Words such as "include" or "comprising" mean that the elements or objects appearing before "include" or "comprising" include the elements or objects listed after "include" or "comprising" and their equivalents, and do not exclude other elements or objects. Words such as "connected" or "connected" are not limited to physical or mechanical connections, nor are they limited to direct or indirect connections. The phrase "A is substantially equal to B" is intended to take into account the tolerances in process manufacturing, that is, the values ​​of A and B can be within ±10% of each other.

[0062] For ease of description, light can be considered to propagate along an optical path from an optically "upstream" position to an optically "downstream" position in a beam. Therefore, the relative position of an optical element in an optical path can also be described using these two terms.

[0063] A suspended display device typically includes an image display unit and an optical system, wherein the image display unit presents an original image on the object plane of the optical system using direct display or indirect projection. The image light then passes through the optical system to form a suspended image in mid-air. To achieve a large-scale suspended display, larger optical components must be processed, which leads to a rapid increase in processing costs and a decrease in the precision of the optical components. Therefore, an optical imaging module is proposed, comprising: a deflection light group comprising at least a first light deflection unit and a second light deflection unit arranged in parallel with each other, wherein the deflection light group modulates light only in a first direction; and a first conjugate imaging element located between the first and second light deflection units in an optical path, wherein the optical path between the first conjugate imaging element and the first light deflection unit is substantially equal to the optical path between the first conjugate imaging element and the second light deflection unit. The optical imaging module is configured to cause a light beam from a point on the object plane to converge on a first image plane in the first direction. The optical imaging module disclosed herein can be used as the above-mentioned optical system to form a suspended image. This solution helps achieve seamless splicing of suspended images while having lower manufacturing costs and making the suspended display device more compact.

[0064] Figures 1A and 1B show schematic diagrams of light propagation of the optical imaging module 100 according to an exemplary embodiment of the present invention, wherein Figure 1A shows a schematic diagram of light propagation of the optical imaging module 100 in the horizontal direction, and Figure 1B shows a schematic diagram of light propagation of the optical imaging module 100 in the vertical direction.

[0065] The optical imaging module 100 may include a first light deflection unit 101, a second light deflection unit 102, and a first conjugate imaging element 103. The first light deflection unit 101 and the second light deflection unit 102 may be arranged parallel to each other and form a deflection light group. As shown in FIG1A , the deflection light group may not modulate the light emitted from the object point O in the x-direction.

[0066] The first conjugate imaging element 103 may be located between the first light deflecting unit 101 and the second light deflecting unit 102 on the optical path, and the optical path between the first conjugate imaging element 103 and the first light deflecting unit 101 is substantially equal to the optical path between the first conjugate imaging element 103 and the second light deflecting unit 102.

[0067] Referring to Figure 1B, the first light deflection unit 101, the second light deflection unit 102 and the first conjugate imaging element 103 can cooperate to make the light beam from the point O on the object plane 10 converge at the point O' on the first image plane 20 in the y direction. The x direction and the y direction are respectively orthogonal to the main optical axis of the optical imaging module 100. The conjugate imaging element can have a microstructure unit for imaging in at least one direction so that the light beam from the point on the object plane 10 converges on the first image plane 20 in the at least one direction. The conjugate imaging element can be transmissive or reflective. As an example, the conjugate imaging element can be a retroreflector, a grid transmission array, a holographic grating, etc. The benefits of using such a conjugate imaging element are: the positional relationship (object and image) is conjugated, the image is not magnified, and there is no aberration.

[0068] The deflection light group can be used to modulate the image height in the y-direction and can be configured to modulate light only in the y-direction. The deflection light group is used to control the height of light passing through the deflection unit to be less than or equal to the physical size of the deflection unit in the y-direction. In some embodiments of the present disclosure, the first light deflection unit 101 can be an aperture stop in the y-direction of the optical imaging module 100, which is used to limit the height of light passing through the optical imaging module 100 in the y-direction.

[0069] Due to the above-mentioned characteristics of the conjugate imaging element, the image height of the first conjugate imaging element 103 in the y direction can be equal to the object height in the y direction. Therefore, the image height of the optical imaging module 100 in the y direction can be adjusted by the deflection light group (the first light deflection unit 101 and the second light deflection unit 102). In some embodiments of the present disclosure, the first light deflection unit 101 and the second light deflection unit 102 can be configured so that the image height of the optical imaging module 100 in the y direction (on the second image plane 20) is equal to the object height in the y direction (on the object plane 10). As shown in Figure 1B, the light beam from point O on the object plane 10 converges at point O' on the first image plane 20 in the y direction, and point O and point O' are at the same height in the y direction. In some embodiments of the present disclosure, the first light deflection unit 101 and the second light deflection unit 102 can be the same lens. It is understood that lenses typically introduce aberrations into an optical system. Therefore, the advantage of using the same lens for the first light deflection unit 101 and the second light deflection unit 102 is that one lens can be used to offset the aberrations of the other lens, thereby achieving a completely mirror-image relationship between the image point O' and the object point O. Therefore, in some embodiments, the first light deflection unit 101 and the second light deflection unit 102 can be mirror-symmetric relative to the first conjugate imaging element 103 in the optical path, and the first light deflection unit 101 and the second light deflection unit 102 can have the same wavefront modulation. As an example, the light deflection unit can include a holographic lens, a metalens, or a gradient index plate.

[0070] In some embodiments of the present disclosure, the first light deflection unit 101 and the second light deflection unit 102 may be lenses. Optionally, the f# of the lens may be greater than or equal to 1.5, which helps ensure sufficient physical space between the first light deflection unit 101 and the second light deflection unit 102 for the folding structure described below. Optionally, the f# of the lens may be less than or equal to 6, which helps ensure a y-direction field of view greater than 10 degrees.

[0071] In some embodiments of the present disclosure, along the principal optical axis, the distance d1 between the first conjugate imaging element 103 and the first light deflecting unit 101 is less than or equal to the focal length f1 of the first light deflecting unit 101. As shown in FIG2A , the maximum angle of light entering the first light deflecting unit 101 is emitted by the object point O. To ensure that all light passing through the first light deflecting unit 101 is modulated by the optical module and then emitted through the light deflecting unit 102 for imaging, the height of all light rays between the light deflecting unit 101 and the first conjugate imaging element 103 is less than or equal to the semi-aperture d of the first light deflecting unit 101. For an optical system in which the first light deflecting unit 101 is a lens, the distance from the object point to the lens is much greater than the focal length of the lens. Therefore, the imaging plane of the object point O is substantially near the focal plane. As can be seen from FIG2A , only at a position less than the focal length f can the light height 1 of light rays passing through the upper edge of the light deflecting unit 101 be guaranteed to be less than the semi-aperture d of the light deflecting unit.

[0072] In some embodiments of the present disclosure, the aperture of the light deflection unit 101 is D, and the distance between the second light deflection unit 102 and the first light deflection unit 101 is greater than or equal to 2D. As shown in FIG2B , the optical imaging module 100 may include a 45-degree beam splitter 105 to form a folding structure. The apertures of the light deflection units 101 / 102 are D, and the shortest optical path from the first conjugate imaging element 103 to the second light deflection unit 102 is 2D. Because the first and second light deflection units 101, 102 can be symmetrically arranged in the optical path relative to the first conjugate imaging element 103, the distance a from the first light deflection unit 101 to the folding structure is ≥ D. Therefore, the distance from the first light deflection unit 101 to the second light deflection unit 103 is greater than or equal to 2D. In order to achieve a larger viewing angle in the y direction, the distance between the first light deflecting unit 101 and the second light deflecting unit 103 is preferably as short as possible. Therefore, the distance between the second light deflecting unit 102 and the first light deflecting unit 101 can be greater than or equal to 2D, preferably equal to 2D.

[0073] In some embodiments of the present disclosure, the first conjugate imaging element 103 may be a two-dimensional conjugate imaging element configured to form images in the x- and y-directions. In this case, as shown in FIG1A , the first conjugate imaging element 103 can cause a light beam originating from point O on the object plane 10 to converge onto the first image plane 20 in the x-direction. By way of example, two-dimensional conjugate imaging elements include, but are not limited to, two-dimensional reflective retroreflectors and two-dimensional transmissive retroreflectors. A two-dimensional reflective retroreflector may have an array of microstructure units, each of which may be a corner cube prism element having three mutually perpendicular adjacent surfaces, as shown in FIG5A or 5B . A two-dimensional transmissive retroreflector may be a structure comprising two stacked glass arrays, wherein each layer of the glass flat array is formed by gluing together several glass flat sheets, each of which is coated with a metal reflective layer on both sides. The glass flat sheets of the two glass arrays are arranged in orthogonal directions. Thus, light passing through the transmissive retroreflector is reflected once on each of the two glass flat arrays, achieving a spatial light retroreflection effect, as shown in FIG6 .

[0074] Figures 3-4 illustrate light propagation diagrams of an optical imaging module 200 according to another exemplary embodiment of the present invention. Figure 3 illustrates light propagation in the horizontal direction of the optical imaging module 200, while Figure 4 illustrates light propagation in the vertical direction of the optical imaging module 200. Several details of the optical imaging module 200 are identical to those of the optical imaging module 100 described above with respect to Figures 1-2 and will not be further described here. The following primarily describes the differences of the optical imaging module 200.

[0075] The first conjugate imaging element 103 may be a conjugate imaging element having a one-dimensional grating structure for converging light in the y direction. The optical imaging module 200 may further include a second conjugate imaging element 104 for converging light in the x direction. The microstructure units of the first conjugate imaging element 103 and the microstructure units of the second conjugate imaging element 104 may be arranged orthogonally. In this way, the second conjugate imaging element 104 can make the light beam from point O on the object plane 10 converge in the x direction on a second image plane 30 different from the first image plane 20, and the x direction and y direction are respectively orthogonal to the main optical axis of the optical imaging module 200. The conjugate imaging element having a one-dimensional grating structure may be a one-dimensional reflective retroreflector, a one-dimensional transmissive retroreflector, a one-dimensional holographic grating, etc. An example of a one-dimensional reflective retroreflector is shown in FIG7 . When any light is irradiated on the surface of a one-dimensional retroreflective screen, a portion of the light is reflected at the original angle in one direction (for example, the X direction shown in FIG7 ). An example of a one-dimensional transmissive retroreflector is shown in Figure 8. It can be constructed by laminating several parallel glass plates, with the laminating surfaces coated with a metal reflective film. The object point o and the image point o' are optically conjugated, resulting in an object plane and image plane of equal size and no aberration. The benefit of using such a conjugated imaging element is that the positional relationship (object and image) is conjugated, the image is not magnified, and there is no aberration.

[0076] The above describes an optical imaging module 100 / 200 according to an exemplary embodiment of the present invention. Optical imaging module 100 / 200 can be used to form a suspended image at image plane 20 and / or image plane 30. Although the suspended image formed by this scheme also has a certain degree of astigmatism, compared to schemes that use a diffuser screen to give the display light a larger divergence angle, the spacing between the first conjugate imaging element 103 and the second conjugate imaging element 104 in this scheme is very small, typically less than 20 mm. This improves the imaging quality of the suspended image and enables a greater spatial depth display. Because the off-screen depth of the suspended image in suspension schemes using diffusers is determined by the distance between the two one-dimensional retroreflective screens, a larger distance increases the suspended depth, but also increases the astigmatism and worsens the imaging quality. In contrast, the suspended display depth of this scheme is determined by the distance between the object plane and the conjugate imaging elements. The distance between the two one-dimensional conjugate imaging elements can be set very small, ensuring that astigmatism does not increase with increasing suspended image depth, thereby increasing the display depth while maintaining suspended image quality.

[0077] According to other exemplary embodiments of the present disclosure, an array imaging module is also provided. As shown in FIG1B or FIG4 , the array imaging module may include a plurality of optical imaging modules 100 / 200 as described above, and these optical imaging modules 100 / 200 are arranged in an array along the y direction, and the optical axes of the first light deflection unit 101 and the second light deflection unit 102 of each optical imaging module are arranged parallel to each other, thereby achieving splicing of the field of view angle in the y direction. It should be noted that although three optical imaging modules 100 / 200 are shown in the accompanying drawings, the present invention is not limited to this. An appropriate number of optical imaging modules 100 / 200 can be selected according to the required size of the suspended image. Such an array imaging module significantly reduces the cost for realizing suspended displays of different sizes, because there is no need to design different optical imaging modules for suspended images of a specific size. It is only necessary to select an appropriate number of optical imaging modules according to the required size of the suspended image, and small-sized optical elements are easier to process than large-sized optical elements.

[0078] Hereinafter, several examples of optical imaging modules and array imaging modules according to embodiments of the present invention will be described.

[0079] First example

[0080] FIG9 is a schematic diagram of an array imaging module 900 according to a first example of the present invention. Several details of the optical imaging module in array imaging module 900 according to the first example are identical to those of optical imaging modules 100 / 200 described above with respect to FIG1-8 and are not further described here. The following primarily describes the unique features of array imaging module 900 according to the first example.

[0081] The array imaging module 900 includes a plurality of optical imaging modules arranged along the y-direction. Each optical imaging module includes a first light deflection unit 901, a second light deflection unit 902, and a first conjugate imaging element 903 as described above. For the sake of simplicity, only the reference numerals of the components of one of the optical imaging modules are marked in FIG9 . The first conjugate imaging element 903 can be a two-dimensional reflective retroreflector. Each optical imaging module of the array imaging module 900 can also include a spectrometer 905 and a reflector 906. The spectrometer 905 can be a semi-reflective and semi-transmissive element, that is, it transmits a portion of the incident light and reflects another portion of the incident light.

[0082] The beam splitter 905 may be tiltedly disposed between the reflector 906 and the first conjugate imaging element 903 and between the first light deflecting unit 901 and the second light deflecting unit 902. The optical axis A of the reflector 906 and the first conjugate imaging element 903 may be perpendicular to the optical axis B of the first light deflecting unit and the second light deflecting unit.

[0083] In the first example, a light beam from the object plane is deflected by the first light deflection unit 901 and then enters the beam splitter element 905. It is then reflected by the beam splitter element 905 and reaches the reflector 906. After reflection by the reflector 906, it is transmitted through the beam splitter element 905 and enters the first conjugate imaging element 903. After reflection by the first conjugate imaging element 903 and then by the beam splitter element 905, it enters the second light deflection unit 902. After being deflected by the second light deflection unit 902, it propagates toward the first image plane 20. As shown in FIG9 , the light beam from the object point O converges at point O' on the first image plane 20 in both the x and y directions through the array imaging module 900.

[0084] It will be appreciated that because the beam splitter element 905 transmits a portion of the incident light and reflects another portion, this can cause a portion of non-imaging light to reach the first image plane 20, affecting imaging quality. In an optional embodiment, the beam splitter element may include a polarization beam splitter 915, a quarter-wave plate 925, and a quarter-wave plate 935, as shown in FIG10 . For example, the polarization beam splitter 915 may reflect S light and transmit P light. The quarter-wave plate 925 may be disposed between the reflector 906 and the polarization beam splitter 915. The quarter-wave plate 935 may be disposed between the first conjugate imaging element and the polarization beam splitter 915.

[0085] The polarization state of the light beam from the object plane can be configured as S polarization (the present invention is not limited to this, and the light emitted from the object plane can also be natural light). The S light is reflected by the polarization beam splitter 915, and the light is reflected by the reflector 906. It then passes through the 1 / 4 wave plate 925 twice, and the main axis direction of the 1 / 4 wave plate is set at 45 degrees with the z axis in the xz plane. The light is converted to P polarized light. After passing through the polarization beam splitter 915, the P light is emitted to the conjugate imaging element 903, which is a two-dimensional retroreflective screen. The light is reflected by the conjugate imaging element (retroreflective screen) 903, and passes through the 1 / 4 wave plate 935 twice. The main axis direction of the 1 / 4 wave plate is set at 45 degrees with the z axis in the xz plane. The polarization state of the light is converted from P polarization to S polarization. After the S polarization light is reflected by the polarization beam splitter plate 915, it is converged at point O' on the first image plane 20 in both the x and y directions through the array imaging module 900.

[0086] In this way, the imaging quality can be improved by polarization splitting, and non-imaging light can be prevented from reaching the first image plane 20. It should be noted that in some embodiments, the polarization beam splitter 915 can also transmit S light and reflect P light; in this case, the polarization state of the light beam from the object plane can be configured to be P polarization.

[0087] Second example

[0088] FIG11 is a schematic diagram of an array imaging module 1100 according to a second example of the present invention. Several details of the optical imaging module in array imaging module 1100 according to the second example are identical to those of optical imaging modules 100 / 200 described above with respect to FIG1-8 and are not further described here. The following primarily describes the unique features of array imaging module 1100 according to the first example.

[0089] Array imaging module 1100 includes multiple optical imaging modules arranged along the y-direction. Each optical imaging module includes a first light deflection unit 1101, a second light deflection unit 1102, a first conjugate imaging element 1103, and a second conjugate imaging element 1104, as described above. For simplicity, FIG11 only shows the reference numerals for the components of one optical imaging module. The first conjugate imaging element 1103 and the second conjugate imaging element 1104 can each be a one-dimensional reflective retroreflector. The microstructure units of the first conjugate imaging element 1103 can be arranged orthogonally to the microstructure units of the second conjugate imaging element 1104.

[0090] Each optical imaging module of the array imaging module 1100 may further include a beam splitter 1105. The beam splitter 1105 may be a semi-reflective and semi-transmissive element, that is, a transflective element that transmits a portion of the incident light and reflects another portion of the incident light.

[0091] The beam splitter element 1105 can be disposed obliquely between the first conjugate imaging element 1103 and the second conjugate imaging element 1104, and between the first light deflection unit 1101 and the second light deflection unit 1102. The first conjugate imaging element 1103 and the second conjugate imaging element 1104 can be disposed relatively parallel to each other. The optical axis A of the first conjugate imaging element 1103 and the second conjugate imaging element 1104 can be perpendicular to the optical axis B of the first light deflection unit 1101 and the second light deflection unit 1102.

[0092] In the second example, a light beam from the object plane is deflected by the first light deflection unit 1101 and then enters the beam splitter element 1105. After reflection from the beam splitter element 1105, it enters the first conjugate imaging element 1103. After reflection from the first conjugate imaging element 1103, it is transmitted through the beam splitter element 1105 and enters the second conjugate imaging element 1104. After reflection from the second conjugate imaging element 1104 and then from the beam splitter element 1105, it enters the second light deflection unit 1102. After being deflected by the second light deflection unit 1102, it propagates toward the first image plane 20 and the second image plane 30. As shown in FIG11 , the light beam from point O on the object plane is converged in the y direction at point O' on the first image plane 20 by the array imaging module 1100, and in the x direction at point O" on the second image plane 30.

[0093] In an alternative embodiment, the beam splitter element may include a polarization beam splitter 1115, a first phase retarder film 1125, and a second phase retarder film 1135, as shown in FIG12 . For example, the polarization beam splitter 1115 may reflect S light and transmit P light. The first phase retarder film 1125 may be disposed between the first conjugate imaging element 1103 and the polarization beam splitter 1115. The second phase retarder film 1135 may be disposed between the second conjugate imaging element 1104 and the polarization beam splitter 1115.

[0094] The polarization state of the light beam from the object plane can be configured as S polarization (the present invention is not limited to this, the light emitted by the object plane can also be natural light), the S light is reflected by the polarization splitter 1115, the light is emitted to the first conjugate imaging element 1103 and then reflected by the reflector, passing through the first phase delay film 1125 twice, the first phase delay film 1125 is a 1 / 2 wave plate, and the main axis direction of the wave plate is set at 22.5° or 67.5° to the z-axis in the xz plane, and the light is converted into P polarized light. After passing through the polarization beam splitter 1115, the P light is emitted to the second conjugate imaging element 1104. The light is reflected by the second conjugate imaging element 1104 and passes through the second phase delay film 1135 twice. The second phase delay film 1135 is a 1 / 2 wave plate. The main axis direction of the wave plate is set at 22.5° or 67.5° with the z-axis in the xz plane. The polarization state of the light is converted from P polarization to S polarization. After being reflected by the polarization beam splitter plate 1115, the S polarization light is converged at point O' on the first image plane 20 in the y direction through the array imaging module 1100, and converged at point O" on the second image plane 30 in the x direction.

[0095] In this way, the imaging quality can be improved by polarization splitting. It should be noted that, in some embodiments, the polarization beam splitter 1115 can also transmit S light and reflect P light; in this case, the polarization state of the light beam from the object plane can be configured as P polarization.

[0096] See Figures 13A and 13B, where Figure 13A shows a schematic diagram of the optical path of an object point O passing through multiple optical imaging modules in the array imaging module 1100 for stitching and imaging, and Figure 13B shows a schematic diagram of the optical path of different object points (a, b, c, d, e, f, g, h, i) passing through a single optical imaging module 1110 in the array imaging module 1100.

[0097] Third example

[0098] FIG14 is a schematic diagram of an array imaging module 1400 according to a third example of the present invention. Several details of the optical imaging module in array imaging module 1400 according to the third example are identical to those of optical imaging module 100 / 200 described above with reference to FIG1-8 and are not further described here. The following primarily describes the unique features of array imaging module 1400 according to the third example.

[0099] Array imaging module 1400 includes multiple optical imaging modules arranged along the y-direction. Each optical imaging module includes a first light deflection unit 1401, a second light deflection unit 1402, and a first conjugate imaging element 1403, as described above. For simplicity, FIG14 only shows the reference numerals for the components of one optical imaging module. First conjugate imaging element 1403 can be a two-dimensional transmissive retroreflector. Each optical imaging module of array imaging module 1400 can also include a reflector 1405.

[0100] In the third example, the surface of a two-dimensional transmissive retroreflector is coated with a semi-reflective and semi-transmissive dichroic film. A light beam from the object plane is deflected by the first light deflection unit 1401 and then enters the two-dimensional transmissive retroreflector 1403. After passing through the two-dimensional transmissive retroreflector 1403, it is transmitted to the reflector 1405. After being reflected by the reflector 1405 and then by the two-dimensional transmissive retroreflector 1403, it enters the second light deflection unit 1402. After being deflected by the second light deflection unit 1402, it propagates toward the first image plane 20. As shown in Figure 14, the light beam from object point O converges in both the x and y directions at point O' on the first image plane 20 through the array imaging module 1400.

[0101] Fourth Example

[0102] Figure 15A illustrates a schematic diagram of an optical imaging module 1510 according to a fourth example of the present invention. Several details of the optical imaging module 1510 according to the fourth example are identical to those of the optical imaging modules 100 / 200 described above with respect to Figures 1-8 and are not further described here. The following primarily describes the unique features of the optical imaging module 1510 according to the fourth example.

[0103] The optical imaging module 1510 may include the first light deflection unit 1501, the second light deflection unit 1502, the first conjugate imaging element 1503, and the second conjugate imaging element 1504 as described above. The first conjugate imaging element 1503 may be a one-dimensional transmissive retroreflector, and the second conjugate imaging element 1504 may be a one-dimensional reflective retroreflector. The first conjugate imaging element 1503 may be disposed obliquely between the first light deflection unit 1501 and the second light deflection unit 1502. The optical axis A of the second conjugate imaging element 1504 may be perpendicular to the optical axes B of the first and second light deflection units 1501 and 1502.

[0104] The optical imaging module 1510 may further include a reflective polarizing film 1505 and a half-wave plate 1506. The reflective polarizing film 1505 may be disposed between the first conjugate imaging element 1503 and the second light deflecting unit 1502, and between the first conjugate imaging element 1503 and the second conjugate imaging element 1504. The half-wave plate 1506 may be disposed between the reflective polarizing film 1505 and the second conjugate imaging element 1504.

[0105] In the fourth example, the light beam from the object plane is deflected by the first light deflection unit 1501 and then enters the one-dimensional transmissive retroreflector 1505, then passes through the one-dimensional transmissive retroreflector 1503 and the reflective polarizing film 1506 and is transmitted to the one-dimensional reflective retroreflector 1504, then is reflected by the one-dimensional reflective retroreflector 1504 and then reflected by the reflective polarizing film 1506 and enters the second light deflection unit 1502, then is deflected by the second light deflection unit 1502 and propagates toward the first image plane and the second image plane. As shown in FIG15A , the polarization state of the light beam from the object plane can be configured as P polarization (the present invention is not limited thereto, and the light emitted by the object plane can also be natural light). The P light converges in the y direction through the one-dimensional transmissive reflector 1503, is transmitted by the reflective polarizing film 1506, and then irradiates the one-dimensional reflective reflector 1504. The P light passes through the half-wave plate 1506 twice and is converted into S light, which is reflected by the reflective polarizing film 1506 and converges at point O on the first image plane in the y direction through the array imaging module, and converges at point O' on the second image plane in the x direction, as shown in FIG15B .

[0106] It should be noted that although the example array imaging module described above includes multiple identical optical imaging modules, the present invention is not limited thereto. The array imaging module may also include multiple different optical imaging modules. In some embodiments of the present invention, the array imaging module may include at least two of the multiple different optical imaging modules described above (e.g., the optical imaging modules in the first, second, third, and fourth examples).

[0107] Fifth Example

[0108] FIG16 is a schematic diagram of an array imaging module 1600 according to a fifth example of the present invention. Several details of the optical imaging module in array imaging module 1600 according to the fifth example are identical to those of optical imaging module 100 / 200 described above with respect to FIG1-8 and are not further described here. The following primarily describes the unique features of array imaging module 1500 according to the fifth example.

[0109] The array imaging module 1500 may include a first optical imaging module 1610, a second optical imaging module 1620, and a third optical imaging module 1630 arranged along the y direction. Adjacent optical imaging modules may share the same optical elements. For example, the optical imaging module 1610 may be the optical imaging module in the third example described above (using a two-dimensional transmissive retroreflector), and the optical imaging module 1620 and the optical imaging module 1630 may be the optical imaging modules in the first example described above (using a two-dimensional reflective retroreflector). As shown in FIG16 , the optical imaging module 1610 and the optical imaging module 1620 may share the same reflector 1612, while the optical imaging module 1620 and the optical imaging module 1630 may share the same two-dimensional reflective retroreflector 1623. In this way, the sharing of optical elements can be achieved, which is beneficial to reducing the number of optical devices required for the array imaging module 1600, thereby further reducing costs.

[0110] If there is a gap between adjacent optical imaging modules in the array imaging module, the suspended image formed on the first image plane 20 will also have a gap when viewed at certain field angles. If you want the gap in the suspended image to be as small as possible, it is necessary to set the spacing between adjacent optical imaging modules in the array imaging module to be as small as possible. In some embodiments of the present invention, the distance between the first light deflection units of adjacent optical imaging modules in any of the array imaging modules described above is less than a preset threshold, which is conducive to reducing the gap width in the suspended image of the first image plane 20. Preferably, the spacing between the first light deflection units of adjacent optical imaging modules can be equal to the aperture of the first light deflection unit, that is, the first light deflection units of adjacent optical imaging modules are close to each other, which is conducive to achieving a seamless suspended image.

[0111] It is understandable that, taking into account process tolerances, small gaps are inevitable between adjacent optical imaging modules in actual production. In an optional embodiment of the present invention, the array imaging module may further include a grating plate 170, which is arranged between the optical imaging module and the image plane, as shown in FIG17A . The grating plate 170 may have shading strips at equal intervals. In this way, the visual effect of the suspended image can be made to look seamless. As shown in FIG17B , the grating plate may be screen-printed with uniform black stripes. When the spacing between the black stripes is relatively small (such as about 200um) and is evenly arranged, it is beneficial to eliminate the gaps in the suspended image. The grating stripes can also be directly screen-printed on the array of light deflection units, forming an integrated structure with the light deflection column units.

[0112] In some embodiments of the present invention, the spaces between the elements in any of the optical imaging modules described above can be filled with a medium having a refractive index greater than 1. Typically, conjugate imaging elements, polarization splitting elements, reflective film layers, and the like all process functional microstructures or film layers onto certain dielectric materials, thereby enabling physical positioning in space. For example, a polarization splitting film needs to be attached to a glass / plastic substrate, and a reflective grating needs to form a reflective microstructure on a glass / plastic flat plate. The presence of these dielectric materials inevitably creates a certain gap, hindering the transmission of light in these dielectric spaces, resulting in gaps in the display of the array imaging module. In order to achieve a seamless suspended display, glue with a refractive index that is the same or close to that of the substrate material can be used to fill the spaces between the components of the entire array optical module. After UV or thermal curing, the glue becomes solid, thereby forming the entire array optical component into a flat plate structure with a consistent and uniform refractive index, with the functional film layer or microstructure distributed at specific locations on the flat plate. This allows for a seamless suspended display, and forming the array optical component into an integrated flat plate structure facilitates assembly with the display module.

[0113] The present invention further provides a suspension display device. FIG18 shows a schematic block diagram of a suspension display device 1800 according to an embodiment of the present invention.

[0114] The suspended display device 1800 may include an array imaging module 1810 and a display module 1820. The display module 1820 has a display surface for an image and emits display light constituting an initial image from the display surface. The display module 1820 may adopt a direct light emitting display method, or may also adopt an indirect projection method to display or project an image on the display surface. In some embodiments, the display module 1820 may include one or more displays. The array imaging module 1810 is arranged optically downstream of the display module 1820 to receive the display light, and has an object plane 10 and an image plane 20 / 30. The array imaging module 1810 may be any one of the various array imaging modules described above. The object plane 10 may be arranged at the display surface of the display module 1820 to receive the original light constituting the initial image at the object plane, and then the original light is modulated by the array imaging module 1810 to form a suspended image (also referred to as an aerial image) at the image plane 20 / 30 in the air. Alternatively, it is conceived that there may be one or more relay optical systems between the display module 1820 and the array imaging module 1810, which can image the display surface of the display module 1820 at the object plane of the array imaging module 1810; in this case, the object plane of the array imaging module 1810 can be located at the image plane where the display surface of the display module 1820 is imaged by one or more relay optical systems.

[0115] According to another exemplary embodiment of the present invention, a multi-layer display device is also provided.

[0116] FIG. 19 shows a schematic diagram of a multi-layer display device 1900 according to an embodiment of the present invention.

[0117] The multi-layer display device 1900 may include the aforementioned suspended display device 1800 and a transparent display device 1910. The transparent display device 1910 may be disposed on the light-emitting side (optically downstream) of the suspended display device 1800. The display surface of the transparent display device 1910 and the suspended image surface 20 / 30 of the suspended display device 1800 are located at different positions, specifically between the suspended image surface 20 / 30 and the suspended display device 1800. The transparent display component 200 may have high transmittance, such as a transparent OLED / LED / LCD display or film (slide). The transparent display device 1910 may also be obtained by micro-projecting an image by disposing a transparent film (the film haze is less than <5%) in front of the suspended display device 1800, as shown in FIG20 . Alternatively, the transparent film may have angular selectivity for light, scattering light at large angles (projecting an image) and directly transmitting light at small angles (suspending an image).

[0118] The above describes a multi-layer display device 1900 according to an exemplary embodiment of the present invention. The multi-layer display device 1900 has a display surface 1 and a display surface 2. The suspended display device 1800 can form a suspended image at the display surface 1 (image surface 20 / 30), and the transparent display device 1910 can display different information at the display surface 2. In this way, secondary information can be displayed on the display surface 2, while important information can be presented at the display surface 1, thereby improving people's efficiency in obtaining information and their experience. Alternatively, images of the same size can be displayed on the display surface 1 and the display surface 2, and the difference in darkness and color caused by the different distances between objects and the viewer can be used to overlap the images of the front and back objects, giving the viewer a sense of three-dimensionality, thereby achieving naked-eye 3D display, as shown in Figure 21.

[0119] Optionally, display module 1820 can also be a naked-eye 3D display. This 3D display can be a multi-viewpoint autostereoscopic display or a light field display. As shown in Figure 22A, a typical naked-eye 3D display consists of a flat-panel display and a micro-optical unit, which can be a microlens or a slit grating. The flat-panel display produces an image with parallax, which is then transmitted to the viewer's left and right eyes respectively after passing through the micro-optical unit. This creates a 3D effect by leveraging the binocular parallax effect of the human eye. As shown in Figure 22B, point a1 on display module 1820 enters the right eye, and point a2 enters the left eye. Due to the principle of binocular parallax, the human eye sees point a, which is in front of the screen. Point b1 on the display screen enters the right eye, and point b2 enters the left eye. Due to the principle of binocular parallax, the human eye sees point b, which is behind the screen. The left and right eyes both see point c on the screen, and therefore perceive point c as being on the screen. Therefore, the 3D image presented by a traditional naked-eye 3D display is a 3D image with the screen as the depth center, within a certain depth range in front and behind. Because the human eye focuses on the physical screen of the 3D display when watching, it is impossible to feel the 3D image floating in the space, which affects the experience.

[0120] The display module 1820 of the present invention can utilize a multi-viewpoint light field display, which effectively solves this problem. The screen of the multi-viewpoint / light field display is projected into space through the optical imaging module 120 of the present invention, forming a suspended image plane. By displaying parallax images on the multi-viewpoint / light field display, a 3D image can be formed in space, with the suspended image plane as the depth center, within a certain range in front and behind. As shown in Figure 22C, on the suspended image plane, point a is in the foreground depth plane, point b is in the background depth plane, and point c is on the suspended image plane of the display device. The resulting 3D image is completely suspended in mid-air, providing a more enhanced 3D experience.

[0121] The display module 1820 in the present invention can also be a two-dimensional light field display. Existing scattering screen suspension solutions lack vertical parallax and cannot be used with two-dimensional light field displays to achieve full parallax 3D display in space. However, the array optical assembly 1810 in the present invention can achieve full parallax suspension display in both horizontal and vertical directions. When used with the two-dimensional light field display module 1820, the central depth plane of the two-dimensional light field display module 1820 can be displayed at a distance from the entire optical module, enhancing the off-screen feel of the light field three-dimensional display. The entire 3D image can be suspended in mid-air for a more striking stereoscopic effect, while also enabling fully immersive interaction with the 3D content.

[0122] The above describes in detail the optical imaging module, array imaging module, suspension display device and multi-layer display device according to the exemplary embodiments of the present invention. The advantages of the present invention are: 1) the optical imaging module has no aberration or only has a small astigmatism; 2) the optical imaging module has a simple structure, and the required optical elements are small in size, easy to process, and can effectively reduce costs; 3) a display module with a specific size and a specific number of optical imaging modules can be used as needed to achieve suspension displays of different sizes, which is conducive to the realization of large-size suspension displays; 4) the optical imaging module is designed once, and the corresponding number of optical imaging modules can be used according to the required suspension image size to seamlessly splice the suspension image, without the need to design different optical imaging modules for different suspension image sizes; 5) the thickness of the suspension display device is small, achieving lightness and thinness; 6) compared with the solution using a scattering screen, full parallax suspension display in the horizontal and vertical directions is achieved, the imaging quality is improved, and a greater spatial depth display can be achieved. The suspension display device is used to achieve light field reconstruction of the display module in the air, which is a light field three-dimensional display technology.

[0123] It should be understood that the above description is illustrative and not restrictive. For example, the above embodiments (and / or their aspects) can be used in combination with each other. In addition, without departing from the scope of the present invention, many modifications can be made to adapt specific conditions or materials to the teachings of the various embodiments of the present invention. Although the size and type of materials described herein are used to define the parameters of the various embodiments of the present invention, the various embodiments are not meant to be restrictive, but rather exemplary embodiments. Upon reading the above description, many other embodiments will be apparent to those skilled in the art. Therefore, the scope of the various embodiments of the present invention should be determined with reference to the appended claims, and the full range of equivalent forms claimed for protection by these claims.

Claims

1. An optical imaging module, comprising: A deflection light group, comprising at least a first light deflection unit and a second light deflection unit arranged in parallel with each other, wherein the deflection light group modulates the light only in a first direction; as well as a first conjugate imaging element, located between the first light deflection unit and the second light deflection unit on the optical path, wherein the optical path between the first conjugate imaging element and the first light deflection unit is substantially equal to the optical path between the first conjugate imaging element and the second light deflection unit, The optical imaging module is configured to converge a light beam from a point on the object plane onto a first image plane in the first direction.

2. The optical imaging module according to claim 1, wherein: The first light deflection unit is an aperture stop of the optical imaging module in the first direction.

3. The optical imaging module according to claim 1, wherein: The first light deflecting unit and the second light deflecting unit are configured to make the image height of the optical imaging module in the first direction equal to the object height in the first direction.

4. The optical imaging module according to claim 1, wherein: The first light deflecting unit and the second light deflecting unit are the same lens.

5. The optical imaging module according to claim 1, wherein: The first light deflection unit is a lens, and its f# is greater than or equal to 1.5 and less than or equal to 6.

6. The optical imaging module according to claim 1, wherein: The aperture of the light deflection unit is D, and the distance between the second light deflection unit and the first light deflection unit is greater than or equal to 2D.

7. The optical imaging module according to claim 1, wherein: Along the optical path, a distance between the first conjugate imaging element and the first light deflecting unit is less than or equal to a focal length of the first light deflecting unit.

8. The optical imaging module according to claim 1, wherein: The first conjugate imaging element is a one-dimensional conjugate imaging element, and the first light deflection unit, the second light deflection unit and the first conjugate imaging element cooperate to make the light beam from the point on the object plane converge on the first image plane in the first direction.

9. The optical imaging module as described in claim 8 further includes a second conjugate imaging element, which is used to make the light beam from the point on the object plane converge on a second image plane different from the first image plane in a second direction, and the first direction and the second direction are respectively orthogonal to the main optical axis of the optical imaging module.

10. The optical imaging module according to claim 9, wherein: The first conjugate imaging element and the second conjugate imaging element are one-dimensional reflective retroreflectors, wherein the microstructure units of the first conjugate imaging element and the microstructure units of the second conjugate imaging element are orthogonally arranged.

11. The optical imaging module according to claim 10, wherein: The first conjugate imaging element and the second conjugate imaging element are arranged relatively parallel, and the optical axes of the first conjugate imaging element and the second conjugate imaging element are perpendicular to the optical axes of the first light deflecting unit and the second light deflecting unit.

12. The optical imaging module according to claim 10, wherein: The optical imaging module also includes a beam splitter element. The light beam from the object plane is deflected by the first light deflection unit and then enters the beam splitter element. After being reflected by the beam splitter element, it enters the first conjugate imaging element. After being reflected by the first conjugate imaging element, it is transmitted through the beam splitter element and then enters the second conjugate imaging element. After being reflected by the second conjugate imaging element, it is reflected by the beam splitter element and then enters the second light deflection unit. After being deflected by the second light deflection unit, it propagates toward the first image plane and the second image plane.

13. The optical imaging module according to claim 12, wherein: The beam splitter element is obliquely disposed between the first conjugate imaging element and the second conjugate imaging element and between the first light deflecting unit and the second light deflecting unit.

14. The optical imaging module according to claim 12, wherein: The light splitting element comprises: Polarization beam splitter; a first phase retardation film disposed between the first conjugate imaging element and the polarization beam splitter; and A second phase retardation film is disposed between the second conjugate imaging element and the polarization beam splitter.

15. The optical imaging module according to claim 1, wherein: The first conjugate imaging element is a two-dimensional conjugate imaging element, and the first light deflection unit, the second light deflection unit and the first conjugate imaging element cooperate to make the light beam from the point on the object plane converge on the first image plane in the first direction, and the first conjugate imaging element is used to make the light beam from the point on the object plane converge on the first image plane in the second direction, and the first direction and the second direction are respectively orthogonal to the main optical axis of the optical imaging module.

16. The optical imaging module according to claim 15, wherein: The first conjugate imaging element is a two-dimensional reflective retroreflector, and the optical imaging module also includes a beam splitter and a reflector. The light beam from the object plane is deflected by the first light deflection unit and then enters the beam splitter, is reflected by the beam splitter to the reflector, is reflected by the reflector and then transmitted through the beam splitter to enter the first conjugate imaging element, is reflected by the first conjugate imaging element and then reflected by the beam splitter, then enters the second light deflection unit, and is deflected by the second light deflection unit and then propagates toward the first image plane.

17. The optical imaging module according to claim 16, wherein: The beam splitter element is obliquely arranged between the reflector and the first conjugate imaging element and between the first light deflection unit and the second light deflection unit, and the optical axes of the reflector and the first conjugate imaging element are perpendicular to the optical axes of the first light deflection unit and the second light deflection unit.

18. The optical imaging module according to claim 16, wherein: The light splitting element comprises: Polarization beam splitter; a first phase delay film disposed between the reflector and the polarization beam splitter; and The second phase delay film is arranged between the first conjugate imaging element and the polarization beam splitter.

19. The optical imaging module according to claim 15, wherein: The first conjugate imaging element is a two-dimensional transmissive retroreflector, and the optical imaging module also includes a reflector. The light beam from the object plane is deflected by the first light deflection unit and then enters the two-dimensional transmissive retroreflector, is transmitted to the reflector through the two-dimensional transmissive retroreflector, is reflected by the reflector, and then is reflected by the two-dimensional transmissive retroreflector before entering the second light deflection unit, and is deflected by the second light deflection unit and then propagates toward the first image plane.

20. The optical imaging module according to claim 9, wherein: The first conjugate imaging element is a one-dimensional transmissive retroreflector, and the second conjugate imaging element is a one-dimensional reflective retroreflector, wherein the first conjugate imaging element is obliquely arranged between the first light deflection unit and the second light deflection unit, and the optical axis of the second conjugate imaging element is perpendicular to the optical axes of the first light deflection unit and the second light deflection unit.

21. The optical imaging module according to claim 20, wherein: The optical imaging module further comprises: a reflective polarizing film, disposed between the first conjugate imaging element and the second light deflecting unit and between the first conjugate imaging element and the second conjugate imaging element; and a phase delay film, arranged between the reflective polarizing film and the second conjugate imaging element, The light beam from the object plane is deflected by the first light deflection unit and then enters the one-dimensional transmissive retroreflector, is transmitted to the one-dimensional reflective retroreflector through the one-dimensional transmissive retroreflector, is reflected by the one-dimensional reflective retroreflector and then reflected by the reflective polarizing film and then enters the second light deflection unit, is deflected by the second light deflection unit and then propagates toward the first image plane and the second image plane.

22. An array imaging module, comprising: A plurality of optical imaging modules as described in any one of claims 1-21 are arranged in an array along the first direction.

23. The array imaging module according to claim 22, characterized in that: The distance between the first light deflection units of adjacent optical imaging modules is smaller than a preset threshold.

24. The array imaging module according to claim 22, characterized in that: Adjacent optical imaging modules have common optical elements.

25. The array imaging module according to claim 22, characterized in that: The array imaging module further comprises a grating plate, which is arranged between the optical imaging module and the image plane, wherein the grating plate has shading strips with equal spacing.

26. The array imaging module according to claim 22, characterized in that: The space between the beam splitting element and the conjugate imaging element in the optical imaging module is filled with a medium, and the refractive index of the medium is greater than 1.

27. A suspension display device, comprising: A display module configured to emit display light constituting a target image; as well as The array imaging module as described in any one of claims 22 to 26; The display light emitted from the display module passes through the array imaging module to form a suspended image at the first image plane and / or the second image plane.

28. The suspension display device according to claim 27, characterized in that: The display module is a three-dimensional display.

29. A multi-layer display device comprising: The suspended display device according to claim 27 or 28; as well as A transparent display device is disposed optically downstream of the suspended display device, wherein a display surface of the transparent display device and the suspended image are located at different positions.

30. The multi-layer display device according to claim 29, characterized in that The transparent display device includes a transparent display or is realized by projecting an image onto a transparent film.

Images