Display module

Abstract

The invention relates to a display module. The display module comprises a coherent light source, a spectroscope, a spatial light modulator, a lens system, a reflector and a volume holographic optical assembly. The spectroscope is located above the coherent light source. The spatial light modulator is located at one side of the spectroscope and is configured to modulate a plurality of light rays, each of which has a different imaging plane than others. The lens system is located on the side, away from the spatial light modulator, of the spectroscope. The reflector is located on one side of the lens system away from the spectroscope. And the volume holographic optical component is positioned above the reflecting mirror. The spatial light modulator is configured to modulate a plurality of light rays, and each of the light rays has an imaging surface different from that of other light rays, so that a driver can see images of different imaging surfaces (namely different distances and distances) on a windshield, message overlapping and visual confusion caused by a single imaging surface are improved, and the driving safety is improved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a display module. Background Art

[0002] At present, the head-up display (HUD) system for vehicles plays an important role in improving driving safety and convenience. The head-up display can project information such as vehicle speed and navigation instructions into the driver's field of view, reducing the need for the driver to look away from the front. Most existing head-up displays use a single imaging surface to present different information. However, this imaging method is prone to information overlap and visual confusion, and it is also impossible to present multi-level distance information at the same time, affecting driving safety. Summary of the invention

[0003] Based on this, it is necessary to provide a display module to address the problem of information overlap and visual confusion caused by a single imaging surface, which leads to driving safety.

[0004] According to a first aspect of the present application, a display module is provided, comprising:

[0005] Coherent light source;

[0006] a beam splitter, located above the coherent light source;

[0007] A spatial light modulator, located on one side of the beam splitter, configured to modulate a plurality of light rays, each of the plurality of light rays having an imaging plane different from the others;

[0008] a lens system, located on a side of the beam splitter away from the spatial light modulator;

[0009] a reflector, located at a side of the lens system away from the beam splitter; and

[0010] The volume holographic optical component is located above the reflecting mirror.

[0011] In some embodiments, the lens system comprises:

[0012] A first lens, located at a side of the beam splitter away from the spatial light modulator;

[0013] a second lens, located on a side of the first lens away from the beam splitter; and

[0014] The filter is located between the first lens and the second lens.

[0015] In some embodiments, the filter is located on a focal plane between the first lens and the second lens.

[0016] In some embodiments, a distance between the spatial light modulator and the first lens is a focal length of the first lens.

[0017] In some embodiments, the lens system is a four-fold focal length system configured to filter high-order stray light of the plurality of light beams modulated by the spatial light modulator.

[0018] In some embodiments, the display module further comprises:

[0019] A windshield is located above the volume holographic optical component and is attached to the volume holographic optical component.

[0020] In some embodiments, the spatial light modulator comprises:

[0021] substrate;

[0022] A lower electrode layer, located on the substrate;

[0023] A first alignment layer, located on the lower electrode layer;

[0024] a liquid crystal layer, located on the first alignment layer;

[0025] A second alignment layer, located on the liquid crystal layer;

[0026] an upper electrode layer, located on the second alignment layer; and

[0027] The encapsulation layer is located on the upper electrode layer.

[0028] In some embodiments, the reflector is configured to reflect a plurality of light rays emitted from the lens system onto the volume holographic optical component.

[0029] In some embodiments, the beam splitter is located between the lens system and the spatial light modulator.

[0030] In some embodiments, the lens system is located between the reflector and the beam splitter.

[0031] In the above-mentioned embodiment of the present application, since the spatial light modulator is configured to modulate multiple light rays, and each of the light rays has an imaging plane different from the others, the driver can see images of different imaging planes (i.e., different distances) on the windshield, thereby improving information overlap and visual confusion caused by a single imaging plane and improving driving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments or exemplary embodiments of the present application, the drawings required for use in the description of the embodiments or exemplary embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 It is a side view of a display module according to an embodiment of the present application.

[0034] Figure 2 for Figure 1 A partial enlarged cross-sectional view of the spatial light modulator in FIG.

[0035] Figure 3 for Figure 1 Side view of the lens system in .

[0036] Figure 4 for Figure 1 A magnified side view of a portion of the vicinity of the spatial light modulator.

[0037] Reference numerals:

[0038] 100: display module;

[0039] 110: coherent light source;

[0040] 120: spectroscope;

[0041] 130: spatial light modulator;

[0042] 132:Substrate;

[0043] 133: lower electrode layer;

[0044] 134: first alignment layer;

[0045] 135: liquid crystal layer;

[0046] 136: second alignment layer;

[0047] 137: upper electrode layer;

[0048] 138: encapsulation layer;

[0049] 140: lens system;

[0050] 142: first lens;

[0051] 144: second lens;

[0052] 146: filter;

[0053] 147: Open your mouth;

[0054] 150: reflector;

[0055] 160: volume holographic optical component;

[0056] 170: windshield;

[0057] A: Modulation capability;

[0058] E: Observer;

[0059] f1,f2: focal length;

[0060] I: input surface;

[0061] O: output surface;

[0062] L1, L2: light;

[0063] S1, S2: imaging positions. DETAILED DESCRIPTION

[0064] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0065] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0066] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0067] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0068] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0069] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0070] Figure 11 is a side view of a display module 100 according to an embodiment of the present application. Referring to FIG. 1 , the display module 100 includes a coherent light source 110, a beam splitter 120, a spatial light modulator 130, a lens system 140, a reflector 150, and a volume holographic optical component 160. The beam splitter 120 is located above the coherent light source 110. The spatial light modulator 130 is located on one side of the beam splitter 120 and is configured to modulate a plurality of light rays L1 and L2, each of which has an imaging plane different from the others. For example, the imaging position S1 of the light ray L1 may be located at a position infinitely far away from the volume holographic optical component 160 (i.e., the image distance is infinite), and the imaging position S2 of the light ray L2 may be located at a position twenty meters away from the volume holographic optical component 160. In FIG. 1 , a group of light rays (for example, the light ray L1) is illustrated as two light rays, however, this representation is only for illustrating the irradiation range of the light ray L1 and is not intended to limit the number of emitted light rays. The lens system 140 is located on a side of the beam splitter 120 away from the spatial light modulator 130. The reflector 150 is located on a side of the lens system 140 away from the beam splitter 120. The volume holographic optical component 160 is located above the reflector 150. In addition, the display module 100 further includes a windshield 170. The windshield 170 is located above the volume holographic optical component 160 and is attached to the volume holographic optical component 160.

[0071] For example, the reflector 150 is configured to reflect a plurality of light rays emitted from the lens system 140 onto the volume holographic optical component 160 .

[0072] In the present embodiment, the beam splitter 120 is located between the lens system 140 and the spatial light modulator 130. In addition, in the present embodiment, the lens system 140 is located between the reflector 150 and the beam splitter 120. In addition, the lower surface of the volume holographic optical component 160 is a curved surface, and the lower surface of the windshield 170 is a curved surface. In other words, the volume holographic optical component 160 has the function of compensating for the curvature of the lower surface of the windshield 170, so that the lower surface of the volume holographic optical component 160 is equivalent to a plane mirror. In practical applications, the curved surface shape of the volume holographic optical component 160 is formed by the interference of two plane waves, and when formed, the volume holographic optical component 160 has the same overall shape as when it is completed, so as to write the curved surface information of the volume holographic optical component 160 into the component.

[0073] Since the spatial light modulator 130 is configured to modulate multiple light beams L1 and L2, and each of the light beams L1 and L2 has an imaging plane different from the others, the driver can see images of different imaging planes (i.e., different distances) on the windshield 170, thereby improving information overlap and visual confusion caused by a single imaging plane and enhancing driving safety.

[0074] Figure 2 for Figure 1 2, the spatial light modulator 130 includes a substrate 132, a lower electrode layer 133, a first alignment layer 134, a liquid crystal layer 135, a second alignment layer 136, an upper electrode layer 137, and an encapsulation layer 138. The lower electrode layer 133 is located on the substrate 132. The first alignment layer 134 is located on the lower electrode layer 133. The liquid crystal layer 135 is located on the first alignment layer 134. The second alignment layer 136 is located on the liquid crystal layer 135. The upper electrode layer 137 is located on the second alignment layer 136. The encapsulation layer 138 is located on the upper electrode layer 137. The material of the substrate 132 may include glass, silicon, or any suitable transparent optical material. In this embodiment, a driving circuit is arranged on the substrate 132 of the spatial light modulator 130, and the driving circuit is configured to control multiple pixels of the spatial light modulator 130 through the lower electrode layer 133 and the upper electrode layer 137. The first alignment layer 134 and the second alignment layer 136 have the same alignment direction, and the first alignment layer 134 and the second alignment layer 136 are configured to control the arrangement of the liquid crystal polymers in the liquid crystal layer 135. The liquid crystal layer 135 includes a plurality of liquid crystal polymers, and the liquid crystal layer 135 is configured to modulate the phase or amplitude of the light L1. In practical applications, the driving circuit controls the arrangement direction of the liquid crystal polymers in the liquid crystal layer 135 through the lower electrode layer 133 and the upper electrode layer 137, thereby changing the refractive index of the liquid crystal layer 135, so as to modulate the phase or amplitude of the light L1.

[0075] Figure 3 for Figure 1 A side view of the lens system 140 in FIG. Figure 1 and Figure 3In this embodiment, the lens system 140 is a four-fold focal length system, configured to filter high-order stray light of the light L1 and L2 modulated by the spatial light modulator 130. The lens system 140 includes a first lens 142, a second lens 144, and a filter 146. The first lens 142 is located on a side of the beam splitter 120 away from the spatial light modulator 130. The second lens 144 is located on a side of the first lens 142 away from the beam splitter 120. The filter 146 is located between the first lens 142 and the second lens 144. In addition, the filter 146 is located on a focal plane between the first lens 142 and the second lens 144. In this embodiment, the first lens 142 is configured to receive light from the input surface I and perform a Fourier transform. The first lens 142 has a focal length f1, and the distance between the input surface I and the first lens 142 is equal to the focal length f1 of the first lens 142. In addition, the distance between the filter 146 and the first lens 142 is equal to the focal length f1 of the first lens 142. Such a design enables the first lens 142 to project light onto the filter 146 (i.e., the focal plane of the first lens 142) and convert it into a spectrum distribution. The second lens 144 has a focal length f2. The second lens 144 is configured to receive the spectrum information converted by the first lens 142 and output the spectrum information to the output surface O after inverse Fourier transform. The distance between the second lens 144 and the output surface O is equal to the focal length f2 of the second lens 144. In addition, the distance between the second lens 144 and the filter 146 is equal to the focal length f2 of the second lens 144. The filter 146 has an opening 147. The opening 147 is configured to allow part of the light to pass through, so as to filter the high-order stray light generated by the spatial light modulator 130. In some embodiments, the filter 146 can be a baffle or a shield. In some embodiments, the filter 146 includes a light-absorbing material or a light-reflecting material.

[0076] Figure 4 for Figure 1 A partial enlarged side view of the vicinity of the spatial light modulator 130 in FIG. Figure 1 and Figure 4 In some embodiments, the spatial light modulator 130 may be a phase modulator. In some embodiments, the spatial light modulator 130 may be an amplitude modulator. In some embodiments, the spatial light modulator 130 may be a combination of a phase modulator and an amplitude modulator. In some embodiments, the distance between the spatial light modulator 130 and the first lens 142 is the focal length f1 of the first lens 142. That is, the spatial light modulator 130 is located at the input surface I (reference Figure 3). The spatial light modulator 130 is configured to calculate the information of the input light. After calculating the wave function φ of the light, the recursive Fourier transform algorithm (IFTA) is introduced to extract the pure phase data of the wave function φ. For use in phase modulators. And conjugate the pure phase data u , the two items are added together to obtain pure amplitude data for use by the amplitude modulator.

[0077] In this embodiment, the spatial light modulator 130 has a modulation capability A. According to the Nyquist-Shannon sampling theorem, when the side length of each pixel of the spatial light modulator 130 is d, the modulation capability A of the spatial light modulator 130 can be expressed as follows:

[0078]

[0079] Where λ is the wavelength of the input light, and f1 is the focal length of the first lens 142. Therefore, the size of the opening 147 of the filter 146 of the lens system 140 is the modulation capability A.

[0080] The foregoing summarizes the features of several embodiments so that those skilled in the art can better understand the spirit of the present application. Those skilled in the art should understand that they can easily use the present application as a basis for designing or modifying other processes and structures to achieve the same purpose and / or achieve the same advantages as the embodiments introduced herein. Those skilled in the art should also recognize that such equivalent constructions do not depart from the spirit and scope of the present application, and that they can make various changes, substitutions and modifications here without departing from the spirit and scope of the present application.

[0081] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there are no contradictions in the combination of these technical features, they should be considered to be within the scope of this specification.

[0082] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A display module, characterized in that: include: Coherent light source; a beam splitter, located above the coherent light source; A spatial light modulator, located on one side of the beam splitter, configured to modulate a plurality of light rays, each of the plurality of light rays having an imaging plane different from the others; a lens system, located on a side of the beam splitter away from the spatial light modulator; a reflector, located at a side of the lens system away from the beam splitter; as well as The volume holographic optical component is located above the reflecting mirror.

2. The display module according to claim 1, characterized in that: The lens system comprises: A first lens, located at a side of the beam splitter away from the spatial light modulator; a second lens, located on a side of the first lens away from the beam splitter; and The filter is located between the first lens and the second lens.

3. The display module according to claim 2, characterized in that: The filter is located on a focal plane between the first lens and the second lens.

4. The display module according to claim 2, characterized in that: A distance between the spatial light modulator and the first lens is the focal length of the first lens.

5. The display module according to claim 1, characterized in that: The lens system is a four-fold focal length system configured to filter high-order stray light of the plurality of light beams modulated by the spatial light modulator.

6. The display module according to claim 1, characterized in that: Also includes: A windshield is located above the volume holographic optical component and is attached to the volume holographic optical component.

7. The display module according to claim 1, characterized in that: The spatial light modulator comprises: substrate; A lower electrode layer, located on the substrate; A first alignment layer, located on the lower electrode layer; A liquid crystal layer, located on the first alignment layer; A second alignment layer, located on the liquid crystal layer; an upper electrode layer, located on the second alignment layer; and The encapsulation layer is located on the upper electrode layer.

8. The display module according to claim 1, characterized in that: The reflector is configured to reflect a plurality of light rays emitted from the lens system onto the volume holographic optical component.

9. The display module according to claim 1, characterized in that: The beam splitter is located between the lens system and the spatial light modulator.

10. The display module according to claim 1, characterized in that: The lens system is located between the reflector and the beam splitter.

Images