Display backlight with light expander structure

Abstract

Methods and systems generally related to information displays, and more specifically, to systems and methods for backlight assemblies for information displays including light expanding structures. Backlight assemblies can include a light expander structure including a plurality of layer sets, where each layer set includes a reflective polarizer layer and a wave retarder layer. The layer sets can work together to convert a point source, such as a laser beam, into a surface light source for use as a backlight for various types of information displays.

Description

Technical Field

[0001] The present invention generally relates to backlighting for displays, and in at least some embodiments to backlighting for close-eye displays or head-mounted displays. Background Technology

[0002] Backlit information displays, such as liquid crystal displays (“LCDs”), comprise several components. Two of these components are the display matrix and the light source, or backlight, which blocks light on a highly granular basis as subpixels to create the displayed image. The light source is typically located behind the display matrix and illuminates the displayed image. For color displays, the backlight typically emits broad-spectrum light, i.e., white light.

[0003] Traditionally, the light source used in backlit displays is typically one or more cold cathode fluorescent lamps ("CCFLs"). Physically, a CCFL resembles a miniaturized version of the fluorescent tubes used in commercial office buildings. However, CCFLs produce light in a different way than those commercial fluorescent lamps. Recently, the use of CCFLs has given way to the use of one or more light-emitting diodes ("LEDs") as the light source in information displays. LED technology is currently the most common type of backlight used in LCD displays.

[0004] Backlighting can generally be divided into two types: edge-type backlighting, which provides light to the display panel through the side surface of the display panel, and direct-type backlighting, which provides light to the display panel through the bottom surface of the display panel. Edge-type backlighting has a light source for generating light and a light guide panel or plate for controlling the direction of light propagation. The light source is located on the side of the light guide panel, and the light guide panel guides the light transmitted from the light source to the display panel. Based on the shape of the beam produced by the light source, the light source is classified, for example, as a point light source, a linear light source, and a surface light source.

[0005] Near-eye display technology can be used to present information and images to a user as part of a virtual reality (“VR”) or augmented reality (“AR”) system. Such near-eye displays can be incorporated into head-mounted display (“HMD”) devices or head-mounted headsets. HMDs can take many forms, including helmets, masks, goggles, face shields, glasses, and other head-mounted or eye-wearing devices. In some implementations, virtual reality and augmented reality systems include add-ons, such as controllers or computers, that generate image information to drive the virtual reality or augmented reality environment. Such environments can be used for a single user or multiple users. HMDs in virtual reality and augmented reality systems can use a single information display or multiple information displays to present images to a user. While these near-eye information displays can be oriented for direct viewing, the information displays are typically coupled to one or more lenses within the HMD. These lenses can enhance the virtual reality or augmented reality experience. Attached Figure Description

[0006] In the accompanying drawings, the same reference numerals denote similar elements or actions. The dimensions and relative positions of the elements in the drawings need not be drawn to scale. For example, the shapes of various elements and angles need not be drawn to scale, and some of these elements may be arbitrarily enlarged and positioned to improve the readability of the drawing. In addition, the specific shape of the elements shown in the figures is not necessarily intended to convey any information about the actual shape of the particular element, and may be chosen simply for ease of identification in the accompanying drawings.

[0007] Figure 1 This is an example of a head-mounted display device including dual display panels according to an embodiment shown.

[0008] Figure 2 This is an example of a laptop computer including a display panel according to an embodiment shown.

[0009] Figure 3 This is an example of a smartphone including a display panel, implemented according to a non-limiting example.

[0010] Figure 4 Aspects of an exemplary backlight assembly according to a non-limiting embodiment are shown.

[0011] Figure 5 Aspects of a front view of an exemplary backlight assembly according to a non-limiting embodiment are shown.

[0012] Figure 6 This is a perspective view of a backlight assembly according to a non-limiting embodiment.

[0013] Figure 7 This is according to a non-limiting embodiment shown. Figure 6A top view of the backlight assembly.

[0014] Figure 8 This is according to a non-limiting embodiment shown. Figure 6 Side view of the backlight assembly.

[0015] Figure 9 This is according to a non-limiting embodiment shown. Figure 6 An enlarged view of a portion of the second light extender structure of the backlight assembly.

[0016] Figure 10 This is according to a non-limiting embodiment shown. Figure 6 A magnified view of a portion of the first light extender structure of the backlight assembly.

[0017] Figure 11 This is a front view of a stack of multiple layers for forming a backlight assembly, according to a non-limiting embodiment.

[0018] Figure 12 It includes, according to a non-limiting embodiment shown. Figure 11 A three-dimensional view of the stacked section of multiple layers.

[0019] Figures 13A to 13C Exemplary steps for manufacturing a backlight assembly according to a non-limiting embodiment are shown. The backlight assembly includes a second light extender structure and a first light extender structure formed by a stack of multiple layers.

[0020] Figure 14 This is a perspective view of a backlight assembly according to a non-limiting embodiment, the backlight assembly including optical components that homogenize light from a light source before it enters a light expander of the backlight assembly. Detailed Implementation

[0021] In the following description, certain specific details are set forth to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the art will recognize that embodiments may be practiced without one or more of these specific details, or using other methods, components, materials, etc. In other instances, well-known structures associated with computer systems, server computers, and / or communication networks have not been shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

[0022] Unless the context otherwise requires, throughout the specification and the following claims, the word “comprising” is synonymous with “including” and is inclusive or open-ended (i.e., does not exclude other unlisted elements or method actions).

[0023] Throughout this specification, the phrase "one embodiment" or "implementation" means that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment. Therefore, the phrases "in one embodiment" or "in an embodiment" appearing in various places throughout the specification do not necessarily refer to the same embodiment. Furthermore, particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0024] The singular forms “a,” “an,” and “the” used in this specification and the appended claims include plural indicators unless the context clearly specifies otherwise. It should also be noted that the term “or” is generally used in its sense as including “and / or” unless the context clearly specifies otherwise.

[0025] The titles and abstracts of this disclosure provided herein are for convenience only and do not constitute an explanation of the scope or meaning of the embodiments.

[0026] One or more embodiments of this disclosure relate to displays for electronic devices, such as head-mounted displays, laptop computers, tablet computers, televisions, smartphones, wearable computers, computer monitors, etc. Figures 1 to 3 The image shows a non-limiting example of an electronic device that may include such a display.

[0027] Liquid crystal displays (LCDs) are a common example of non-emissive displays that require a separate light source, referred to as a backlight unit or backlight assembly. The backlight assembly provides such a display with uniform, bright light having appropriate color characteristics. Recently, backlight technology has become more important due to the advent of edge-lit light-emitting diode (LED) backlighting, which allows displays to be thinner than previous displays while also reducing power consumption. To meet energy regulations or other requirements, it is important that the backlight assembly be as efficient as possible. As discussed further below, this disclosure improves the performance of backlight assemblies by providing a backlight assembly that includes a beam expander structure that expands the collimated beam in multiple dimensions to produce an extended surface light source that is highly efficient compared to existing technologies.

[0028] Figure 1A non-limiting example of an electronic device in the form of a head-mounted display (HMD) device 100 is shown, which can optionally be coupled to a video rendering computing system via a wired or wireless connection to provide a virtual reality display to a human user. In operation, the user wears the HMD device 100 on their head, secured by one or more straps 101, and receives information from the computing system, displayed at each eye, via displays 102a and 102b supported by a support structure 116 of the HMD device. This simulated environment differs from the actual physical environment, wherein the computing system acts as an image rendering system, providing images of the simulated environment to the HMD device for display to the user, such as images generated by a game program (not shown) and / or other software programs (not shown) running on the computing system. In this example, the user can also move around the actual physical environment and may have one or more I / O (“input / output”) devices to allow further interaction with the simulated environment, such as a handheld controller communicatively connected to a computing system via a wired or wireless connection. The HMD device may include one or more user interfaces 104 and 106 that allow the user to provide input to the HMD device 100 or a computing system connected to the HMD device. The position of the HMD device can be tracked as the user moves the location of the HMD device 100 and / or changes its orientation to allow the corresponding portion of the simulated environment to be displayed to the user on the HMD device, and the controller may also employ similar techniques to track its position (and optionally use this information to help determine and / or verify the position of the HMD device). Once the tracked position of the HMD device 100 is known, the corresponding information is sent to the computing system, which uses the tracked position information to generate one or more subsequent images of the simulated environment to be displayed to the user via displays 102a and 102b.

[0029] Figure 2 An example electronic device in the form of a laptop computer 200 is shown. The laptop computer 200 has an upper housing 202 and a lower housing 204 connected together by a hinge 206, which allows the housings to rotate relative to each other. The lower housing 204 includes a keyboard 208 and may include other structures (e.g., a touchpad, various ports). The upper housing 202 includes a display panel 210 for displaying content to a user.

[0030] Figure 3An example electronic device in the form of a smartphone 300 is shown. The smartphone 300 includes a housing 302, which includes a display panel 304 and a plurality of input components 306 (e.g., buttons). In at least some embodiments, the display panel 304 may be, for example, a touchscreen display.

[0031] More generally, the display of this disclosure can be implemented in any type of electronic device, such as Figures 1 to 3 The device shown may be, or may be, a music player, gaming device, navigation unit, vehicle display, wearable device, self-service terminal (kiosk) or other type of device, or may be, a device that includes one or more displays.

[0032] Figure 4 An exemplary backlit LCD display 400 with a backlight assembly is shown in a head-mounted display configuration, wherein the head-mounted display is configured, for example, in a virtual reality or augmented reality head-mounted device. Figure 4 A backlight assembly 402 is shown, which emits light 430 through the LCD 410 to display a visible image. The LCD may optionally include a diffuser layer 404 to produce more uniform light, and in at least some embodiments may optionally include a reflective polarizer layer 406 to recycle light for improved efficiency. Light 440 exiting the LCD 410 then passes through a lens assembly 420, which includes one or more lenses. In some embodiments, the one or more lenses in the lens assembly 420 may be conventional spherical, aspherical, Fresnel, or any other type of imaging lens. The lens assembly 420 may have a single type of lens surface or may be a combination of lens types. In some embodiments, the lens assembly 420 may have a pancake-shaped structure, which may include a polarization-based reflective or refractive optical system. In this case, the lens assembly 420 may include an optical element assembly configured to direct light from the LCD 410 to the user's eye 460 using coaxial optical folding that is at least partially based on the polarization of light. The lens assembly 420 may include various optical elements other than lenses. For example, lens assembly 420 may include at least one polarizing beam splitter and a substrate including a twisted liquid crystal element. The twisted liquid crystal element may be configured to modify the phase of light within lens assembly 420. Light 450 exits lens assembly 420 directed towards user's eye 460. In some embodiments, light 450 creates an eye box of approximately 10 mm (e.g., 5 mm–25 mm, etc.). Those skilled in the art will recognize that... Figure 4 This does not mean describing the physical design or layout of an HMD system, but rather describing the general flow of light between components described in some implementations.

[0033] In some implementations, the head-mounted display is designed to be seen by both the user's left and right eyes. This can be achieved using separate left and right LCD displays, or using a single LCD display. Similarly, virtual reality or augmented reality head-mounted devices may include a single lens assembly, or may use separate left and right lens assemblies.

[0034] Figure 5 Aspects of a front view of an exemplary backlight assembly 500 according to certain embodiments of the present disclosure are shown. The backlight assembly 500 may include an elongated first light extender structure 502 and a rectangular (e.g., square) second light extender structure 504. The length and width of the second light extender structure may be substantially the same as the length and width of a display to which the backlight assembly is a part. The first light extender structure 502 may receive incident light 508 from a light source 506 (e.g., one or more laser light sources) and may redirect the incident light 508 toward the second light extender structure 504. In this configuration, the incident light 508 is received at the edge of the first light extender structure 502 and output as redirected light 510 from the plane of the first light extender structure. The redirected light 510 may then be received at the edge of the second light extender structure 504, and the second light extender structure may redirect the light 510 upward toward the pixelated display panel (e.g., toward...). Figure 4 The light 512 (as shown in the figure, emerges from the page) of the LCD 410. Therefore, the emitted light 512 is output from the plane of the second light extender structure 504. This light 512 is thus emitted from the backlight assembly 500. In some embodiments, the light 512 may pass through an additional component before being received at the pixelated display panel.

[0035] Figure 6 A perspective view of an exemplary light guide panel assembly 600 for a backlight assembly according to one or more embodiments of the present disclosure is shown. Various other views of the light guide panel assembly 600 are shown in... Figures 7 to 10 As shown in the diagram. The light guide panel assembly 600 can be a component in any type of display, such as the display discussed herein.

[0036] The light guide panel assembly 600 includes a first light expander structure 602 and a second light expander structure 604. The first light expander structure 602 and the second light expander structure 604 may be similar to or identical to the first light expander structure 502 and the second light expander structure 504, respectively. The first light expander structure 602 and the second light expander structure 604 may be joined together by a suitable optically clear adhesive (OCA). The first light expander structure 602 may include a strip-shaped elongated waveguide arranged adjacent to and parallel to the edge of the second light expander structure 604. The first light expander structure 602 is used to receive and redirect light 616 radiated from a light source 614 in the longitudinal (x) direction of the first light expander structure 602. The light source 614 may be one or more laser sources (e.g., red, green, and blue semiconductor lasers) that emit polarized beams 616 having specific dimensions (e.g., 1-5 mm × 1-5 mm square, Gaussian, etc.). Light source 614 may include multiple laser sources, each emitting light of a different color (e.g., red, green, blue). Light source 614 may emit linearly polarized coherent light having a first polarization state (e.g., horizontal polarization). Light source 614 may include one or more other light sources and optional lenses that provide collimated light to light extender structure 602.

[0037] like Figure 7 and Figure 10 As shown, the first optical expander structure 602 may include a first plurality of layer groups (e.g., 3 to 50 layer groups), wherein each layer group includes a substrate 608 (e.g., plastic) and a layer 608 including a reflective polarizer layer 611 and a wave delayer layer 613. The reflective polarizer layer 611 and the wave delayer layer 613 are oriented at a 45-degree angle relative to the light 616 received from the light source 614, and the light 616 passes through the first optical expander structure (designated as light 618 within structure 602).

[0038] Each of the reflective polarizer layers 611 can be configured to reflect linearly polarized light having a second polarization state (e.g., vertical polarization) orthogonal to the polarized light emitted by the light source 614. The reflective polarizer layer 611 may include a polarizer film (e.g., DBEF), a wire grid polarizer (WGP), or any other suitable reflective polarizer for implementing the functions discussed herein.

[0039] Since the reflective polarizer layer 611 is not an ideal reflective polarizer, it does not simply reflect 100% of vertically polarized light and transmit 100% of non-vertically polarized light. Instead, even for purely horizontally polarized light, the reflective polarizer layer 611 reflects a small percentage (e.g., 5-15%) of the light and transmits the remaining light (e.g., 85-95%).

[0040] Wave delay layers 613 are configured to shift the polarization orientation of light by a defined rotational amount (e.g., 5-20 degrees). Each of the wave delay layers 613 may be a half-wave plate, a quarter-wave plate, or any other suitable wave delayer operatively shifting or rotating the polarization orientation of light by a predetermined amount. Wave delay layers 613 may each shift the polarization orientation by the same amount, or different wave delay layers may shift the polarization orientation by varying amounts. As a non-limiting example, a first group of wave delay layers 613 may provide a 10-degree rotational shift, a second group of wave delay layers may provide a 15-degree shift, and a third group of wave delay layers may provide a 20-degree shift. The number of delay layers in each group may be the same or different.

[0041] like Figure 7 and Figure 9 As shown, the second optical expander structure 604 may include a second plurality of layer groups (e.g., 3 to 50 layer groups, or more), wherein each layer group includes a substrate 612 (e.g., acrylic or other plastic) and a layer 610, the layer 610 including a reflective polarizer layer 611 and a wave delayer layer 613. The reflective polarizer layer 611 and the wave delayer layer 613 are oriented at a 45-degree angle relative to the light 620 received from the first optical expander structure 602, as discussed further below.

[0042] In operation, according to a non-limiting example, a collimated beam of horizontally polarized light 616 from light source 614 enters the edge of the first light expander structure 602. When light 618 reaches each reflective polarizer 611 of the wave delay layer 613, a small portion of the light (e.g., 5-15%) (indicated by arrow 620) is reflected in the 'y' direction toward the second light expander structure 604, and the remaining portion of the light (e.g., 85-95%) is rotated by the subsequent wave delay layer 613 to produce light 618a (…). Figure 10 The light 618a rotates by a predetermined amount (e.g., 10 degrees, 15 degrees, 20 degrees). Thus, as the light 618a propagates along the first optical expander structure 602 in the 'x' direction, a portion of the light is guided along the second optical expander structure 604 in the 'x' direction by each reflective polarizer 611 of the first optical expander structure 602.

[0043] The operation of the second light extender structure 604 is similar. Light 620 propagating from the first light extender structure 602 in the 'y' direction is received by the second light extender structure 604 at intervals determined by the position of the reflective polarizer layer 611 of the first light extender structure 602. When light 620 reaches each reflective polarizer 611 and subsequent wave delay layer 613 of the second light extender structure 604, a small fraction of the light (e.g., 5-15%) (indicated by arrow 622) is directed toward the display module in the 'z' direction. Figure 6 (Not shown in the image) is reflected, and the remaining portion (e.g., 85-95%) is rotated by a subsequent wave delay layer 613 to produce light 620a with a rotation determined by a specific amount (e.g., 10 degrees, 15 degrees, 20 degrees). Figure 9 Therefore, as light 620 travels along the second light extender structure 602 in the 'y' direction, a portion of the light is directed upwards (as shown) towards the display module along the 'z' direction of the second light extender structure 604. Since the light 620 from the first light extender structure 602 is distributed along the 'x' dimension of the second light extender structure 604, the light 622 emitted by the second light extender structure 604 provides substantially uniform surface illumination to the display module in the 'z' direction.

[0044] The number of reflective polarizer layers, the number of wave delayer layers, and the amount of rotation provided by each wave delayer layer can be designed to provide uniform light throughout the entire region of the second light extension structure 604. Additionally, although not shown, various components may have one or more additional reflective layers disposed adjacent to one or more edges, thereby enabling light recycling, which can improve efficiency.

[0045] Figures 11 to 1 3 illustrates a non-limiting example of a method for manufacturing a light guide panel assembly, wherein the light guide panel assembly is, for example, Figures 6 to 10 The light guide panel assembly 600 shown is illustrated.

[0046] Initially, a group 1100 may be formed of multiple stacked layer groups 1102. Each of these multiple stacked layer groups may include a substrate layer 1108 (e.g., acrylic or other plastic), a wave delay layer 1104, and a reflective polarizer layer 1106. Although 10 layer groups 1102 are shown in this exemplary embodiment, it should be understood that the number of stacked layer groups can be selected based on a specific application. For example, there may be 3 layer groups, 5 layer groups, 10 layer groups, 20 layer groups, 25 layer groups, 50 layer groups, 100 layer groups, etc.

[0047] Then, as Figure 11 and Figure 12 As shown, the intermediate light guide panel assembly 1110 can be formed by cutting multiple stacked layers at a 45-degree angle. Note that in Figure 12 For clarity, layer group 1102 is shown only on one edge of stack 1100.

[0048] Figures 13A to 13C It shows from Figure 11 and Figure 12 The steps of the method for manufacturing the first light extender structure 602 and the second light extender structure 604 in the intermediate light guide panel assembly 1110 shown are described.

[0049] like Figure 13A As shown, a portion of the intermediate light guide panel assembly 1110 can be cut to form a first light extender structure 602 and a second light extender structure 604. For example... Figure 13B As shown, the first optical extender structure 602 can rotate about the 'z' axis and move relative to the second optical extender structure 604 to approach the lower right edge of the second optical extender structure (as shown in the figure). Figure 13C As shown, the first light extender structure 602 can also be rotated clockwise about the 'x' axis (as shown) and (e.g., via OCA) coupled to the second light extender structure 602 to form the light guide panel assembly 600 discussed herein.

[0050] Figure 14 Is it still there? Figure 6 The diagram shows a perspective view of a backlight assembly 600, which includes an optical component 1400 that homogenizes light from a light source 614 before it enters a first light expander structure 602 of the backlight assembly. The optical component 1400 may include a microlens array (as shown), comprising a plurality of microlenses 1402 (e.g., a 5×5 array, a 10×10 array, etc.). In at least some embodiments, the optical component 1400 may additionally or alternatively include a diffuser, another type of optical component, or a combination of two or more components for homogenizing light 616 emitted by the light source 614 to provide homogenized light 1404 to the first light expander structure 602 of the backlight assembly 600.

[0051] The microlens array 1400 can be used to homogenize various modern light sources 614, including laser diodes, high-power LEDs, etc. The microlens array 1400 can advantageously provide high efficiency and non-Gaussian uniformity for light.

[0052] The microlens array 1400 can be used for beam homogenization and shaping to change the light from the light source 614 from a Gaussian pattern to a dot pattern or a square “flat-top” pattern. Thus, when the light is spread as discussed herein, the light is substantially more uniform than if the light remained in a Gaussian pattern. As a non-limiting example, the microlens array 1400 may include a plurality of square microlenses. Additionally, as described above, the optical component 1400 may include one or more optical components (e.g., a microlens array and a second lens, a microlens array and a diffuser, etc.) to provide homogenized light to the light expander structures 602 and 604 of the backlight assembly 600.

[0053] Those skilled in the art will recognize that many of the methods or algorithms described herein may employ additional actions, omit some actions, and / or perform actions in a different order than specified. The various embodiments described above may be combined to provide further embodiments. These and other changes may be made to the embodiments based on the detailed description above. Generally, the terminology used in the following claims should not be construed as limiting the claims to the specific embodiments disclosed in the specification and claims, but should be construed as including all possible embodiments and the full scope of equivalents granted by these claims. Therefore, the claims are not limited to this disclosure.

Claims

1. A display device, comprising: Display module; as well as A backlight assembly provides light to the display module, the backlight assembly comprising: Light source; and Light guide panel assembly, the light guide panel assembly comprising: A first optical expander structure is positioned to receive light from the light source. The first optical expander structure includes a first plurality of layer groups, each of the first plurality of layer groups including a reflective polarizer layer and a wave delayer layer; and A second light extender structure, positioned adjacent to the first light extender structure, receives light from the first light extender structure and emits light toward the display module. The second light extender structure includes a second plurality of layer groups, each of which includes a reflective polarizer layer and a wave delay layer. The second light extender structure is rectangular, and its length and width are the same as the length and width of the display module, of which the backlight assembly is a portion. Each wave delay layer in the first plurality of layer groups and the second plurality of layer groups is configured to rotate the polarization direction of light by a predetermined amount between 5 and 20 degrees.

2. The display device according to claim 1, wherein, The light source emits a coherent beam of light that is linearly polarized in a first polarization state, and the reflective polarizer layer in the first plurality of layers is configured to reflect light that is linearly polarized in a second polarization state, which is orthogonal to the first polarization state.

3. The display device according to claim 1, wherein, Each of the wave delay layers in the first plurality of layer groups and the wave delay layers in the second plurality of layer groups includes a half-wave plate.

4. The display device according to claim 1, wherein, At least one of the wave delay layers of the first plurality of layer groups and the second plurality of layer groups shifts the polarization direction of light by a certain amount, which is different from the amount of shift provided by at least one of the wave delay layers of the first plurality of layer groups and the second plurality of layer groups.

5. The display device according to claim 1, wherein, Each of the reflective polarizer layers and each of the wave delay layers is oriented at a 45-degree angle relative to the light incident on the reflective polarizer layer and the wave delay layer.

6. The display device according to claim 1, wherein, Each of the first plurality of layer groups and the second plurality of layer groups includes a transparent plastic layer.

7. The display device according to claim 1, wherein, Each of the first plurality of layer groups and the second plurality of layer groups comprises 3 to 50 layer groups.

8. The display device according to claim 1, wherein, Each of the reflective polarizer layers includes at least one of a reflective polarizer film or a wire grid polarizer.

9. The display device according to claim 1, wherein, Each of the wave delay layers in the first plurality of layer groups and the second plurality of layer groups includes a quarter-wave plate.

10. The display device according to claim 1, wherein, The light source emits light in a first direction, the first light extender structure is used to guide the light received from the light source in a second direction orthogonal to the first direction, and the second light extender structure is used to guide the light received from the first light extender structure in a third direction orthogonal to the first direction and the second direction.

11. The display device according to claim 1, wherein, The first light extender structure is attached to the second light extender structure by an optically transparent adhesive.

12. The display device according to claim 1, further comprising a diffuse layer located between the backlight assembly and the display module.

13. The display device according to claim 1, wherein, The light source includes multiple lasers, each emitting light of a different color.

14. The display device according to claim 1, wherein, The light source includes at least one of the following: Lasers that produce coherent light; or Collimating lens assembly.

15. The display device according to claim 1, further comprising: A lens array is located between the light source and the light guide panel assembly to homogenize the light emitted by the light source before the light emitted by the light source enters the first light expander structure of the light guide panel assembly.

16. The display device according to claim 1, further comprising: A diffuser, located between the light source and the light guide panel assembly, homogenizes the light emitted by the light source before it enters the first light expander structure of the light guide panel assembly.

17. A light guide panel assembly, comprising: A first optical expander structure is positioned to receive light from a light source. The first optical expander structure includes a first plurality of layer groups, each of which includes a reflective polarizer layer and a wave delayer layer. as well as A second light extender structure, positioned adjacent to the first light extender structure, receives light from the first light extender structure and emits light toward the display module. The second light extender structure includes a second plurality of layer groups, each of which includes a reflective polarizer layer and a wave delay layer. The second light extender structure is rectangular, and its length and width are the same as the length and width of the display module, of which the backlight assembly is a portion. Each wave delay layer in the first plurality of layer groups and the second plurality of layer groups is configured to rotate the polarization direction of light by a predetermined amount between 5 and 20 degrees.

18. The light guide panel assembly according to claim 17, wherein, The reflective polarizer layer in the first plurality of layer groups is configured to reflect light that is linearly polarized to a polarization state orthogonal to the polarization state of the light emitted by the light source.

19. The light guide panel assembly according to claim 17, wherein, Each of the wave delay layers in the first plurality of layer groups and the wave delay layers in the second plurality of layer groups includes one of a half-wave plate or a quarter-wave plate.

20. The light guide panel assembly according to claim 17, wherein, At least one of the wave delay layers of the first plurality of layer groups and the second plurality of layer groups shifts the polarization direction of light by a certain amount, which is different from the amount of shift provided by at least another of the wave delay layers of the first plurality of layer groups and the second plurality of layer groups.

21. The light guide panel assembly according to claim 17, wherein, Each of the reflective polarizer layers and each of the wave delay layers is oriented at a 45-degree angle relative to the light incident on the reflective polarizer layer and the wave delay layer.

22. The light guide panel assembly according to claim 17, wherein, Each of the first plurality of layer groups and the second plurality of layer groups comprises 3 to 50 layer groups.

23. The light guide panel assembly according to claim 17, wherein, The first light extender structure is used to receive light from the light source along a first direction and guide the received light along a second direction orthogonal to the first direction, and the second light extender structure is used to guide the light received from the first light extender structure along a third direction orthogonal to the first direction and the second direction.

24. The light guide panel assembly according to claim 17, wherein, The first light extender structure is attached to the second light extender structure by an optically transparent adhesive.

25. A method for manufacturing a light guide panel assembly, comprising: Multiple stacked layer groups are formed, each of which includes a reflective polarizer layer, a wave delayer layer, and a plastic layer; The multiple stacked layers are cut at a 45-degree angle to generate an intermediate light guide panel assembly; Cut a portion of the intermediate light guide panel assembly to form a first light extender structure and a second light extender structure; Rotate the first light expander structure relative to the second light expander structure; as well as The rotated first light extender structure is connected to the second light extender structure to form the light guide panel assembly.

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