Backlight display device with tapered light cup array

Abstract

The present invention discloses a backlight display device having an array of conical light cups, comprising a plurality of light sources arranged in an array, a plurality of conical light cups arranged in an array, a diffuser, a display module for displaying images, and an imaging concave mirror. The aforementioned components are arranged sequentially along a light path. Each conical light cup has a different inclination angle and corresponds to a light source, respectively, to set the light output angle of each light source. Light from the light source forms a backlight source after passing through the diffuser. The display module and the backlight source are respectively located within and outside the focal length of the imaging concave mirror. The image light formed by the backlight source illuminating the image is projected by the imaging concave mirror onto a single eye box. Each light source only illuminates a portion of the display module. The extended light path of the center normal of each conical light cup intersects at the center position of the single eye box.

Description

Technical Field

[0001] The present invention relates to a backlight display device, more precisely, to a backlight display device having a conical light cup array. Background Art

[0002] Backlit display devices create images by illuminating the display module (such as a TFT panel) with a light-emitting module behind it, which illuminates the display module's pixels. This directs the image light forward and into the viewer's field of view. The backlight provided by the light-emitting module largely determines the quality of the image light. Therefore, multiple optical elements are typically placed between the light source of the light-emitting module and the display module to achieve uniform light distribution and adjust light intensity. Summary of the Invention

[0003] An object of the present invention is to provide a backlight display device having a conical light cup array.

[0004] To achieve the above-mentioned objectives, the present invention provides a backlight display device having a conical light cup array, which includes a light emitting array, a conical light cup array, a diffuser, and a display module. The light emitting array includes a plurality of light sources for projecting light. The conical light cup array includes a plurality of conical light cups, each of which is tilted at a different angle and is disposed on the light-emitting side of the light emitting array. Each conical light cup corresponds to a light source, and is used to set the light-emitting angle of each light source. The diffuser is disposed on the light-emitting side of the conical light cup array to increase the uniformity of the light and form a backlight source. The display module displays an image and is disposed on the light-emitting side of the diffuser to receive the backlight source and emit an image light. The imaging concave mirror is disposed on the light-emitting side of the display module. The display module and the backlight source are respectively located within and outside the focal length of the imaging concave mirror, so as to form a virtual image of the image and a real image of the backlight source, that is, a single eye box. Each light source is configured to illuminate only a portion of the display module, and when all light sources are illuminated, the display module is fully illuminated. The center normal of each conical light cup intersects at the center of a single eye box after extending along the optical path.

[0005] Preferably, the conical light cup is a hollow light cup with a reflective coating on its surface, or the conical light cup is a cup-shaped transparent solid light guide.

[0006] Preferably, each conical light cup is a square cone, the boundaries of the light outlets of adjacent conical light cups are connected to each other, and the light outlets of each conical light cup are aligned and located on the same plane to form a horizontal plane light source.

[0007] Preferably, the display module is a TFT panel.

[0008] Preferably, the diffuser is in a flat plate shape.

[0009] Preferably, there is a gap between the light incident side of the diffuser and the light emitting sides of the plurality of conical light cups.

[0010] Preferably, a convex lens array is further included between the light-emitting side of the diffusion sheet and the light-incident side of the display module to converge the backlight source and then project it onto the display module.

[0011] Preferably, an imaging concave mirror and a windshield are further included between the display module and the single eye box in the optical path. The imaging concave mirror reflects the image light projected by the display module to the windshield, and the windshield reflects the image light to the single eye box.

[0012] Preferably, the display module is arranged within the focal length of the imaging concave mirror, the equivalent distance of the light emitting array is greater than the focal length of the imaging concave mirror, and the real image formed by the light emitting array is located inside the windshield.

[0013] Preferably, the light emitting array is an LED array. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Schematic diagram of an embodiment of a conical light cup.

[0015] Figure 2 It is a schematic diagram of the structure and optical path of the display device.

[0016] Figure 3 It is a schematic diagram of the structure and optical path of the head-up display device.

[0017] Figure 4 FIG. 4 is a schematic diagram of another embodiment of a display device.

[0018] Explanation of the accompanying figures: 0-flat aluminum substrate; 1-light-emitting array; 11-light source; 2-conical light cup array; 21-conical light cup; 25, 31, 41, 71-light incident side; 26, 32-light exit side; 3-diffuser; 4-display module; 5-imaging concave mirror; 6-windshield; 7-convex lens array; D-image light; E-eye box; F-normal; L-backlight source; I-virtual image. DETAILED DESCRIPTION

[0019] The following description is based on the light emitting direction of the light emitting array 1 as the front, so as to conform to the common understanding of those skilled in the art.

[0020] like Figures 1 to 3 The illustrated embodiment is a display device with a conical light cup array backlight, comprising a light emitting array 1 , a conical light cup array 2 , a diffuser 3 , a display module 4 and an imaging concave mirror 5 .

[0021] The light array 1 is composed of a plurality of light sources 11. For example, the light array 1 is an LED array disposed on a flat aluminum substrate 0. The light array 1 module is used to provide a backlight source.

[0022] The conical light cup array 2 is composed of a plurality of conical light cups 21, each tilted at a different angle. Each conical light cup 21 defines a light entrance side 25 and a light exit side 26. Each light source 11 (LED) corresponds to and is located on the light entrance side 25 of a conical light cup 21. The conical light cup 21 can be a hollow light cup with a high-reflectivity coating or a transparent, solid light guide in the form of a cup. Light within the conical light cup 21 is totally reflected when it strikes the cup wall. The conical light cup array 2 is positioned on the light exit side of the light array 1. The point light from the LED is reflected within the conical light cup 21 and projected onto the light exit side 26. Each conical light cup 21 corresponds to a light source 11, setting the light exit angle for each light source 11.

[0023] exist Figure 1 In the illustrated embodiment, each conical light cup 21 of the conical light cup array 2 is a square cone having a square light entrance side 25 (light entrance) and a square light exit side 26 (light exit). The boundaries of the light exits of adjacent conical light cups 21 are connected to each other.

[0024] The light-entry side 31 of the diffuser 3 is aligned with the light-exiting side 26 of the conical light cup 21 to increase the backlight's uniformity. A gap exists between the light-entry side 31 of the diffuser 3 and the light-exiting side 26 of the conical light cup 21. That is, the diffuser 3 does not completely adhere to the light-exiting side 26 of the conical light cup 21. This prevents the dark shadows created by the interface between the conical light cups 21 from being projected forward.

[0025] The display module 4 is a TFT panel for displaying an image. The light incident side 41 of the display module 4 is aligned with the light emitting side 32 of the diffusion sheet 3 for receiving the backlight source and emitting an image light D.

[0026] An imaging concave mirror 5 is disposed on the light-emitting side 42 of the display module 4. The display module 4 is located within the focal length of the imaging concave mirror 5, so that the image is formed into a virtual image I. The backlight source is located outside the focal length of the imaging concave mirror 5, so that the backlight light is reflected by the imaging concave mirror 5 to form a real backlight image, namely, a single eye box E.

[0027] Figure 2This is a schematic diagram of a backlight module used in a display device. The conical light cup array 2 is composed of a plurality of conical light cups 21 with varying degrees of inclination. The light outlets of each conical light cup 21 are aligned and located on the same plane, providing a horizontal light source along the entire light-exiting side 26. The light-exiting side 26 of the conical light cups 21, the diffuser 3, and the light-entering side 41 of the display module 4 are spaced apart and parallel to one another. The center normal F of each conical light cup 21 intersects at the center of a single eyebox E as the light path extends. Each light source 11 illuminates only a portion of the display module 4. Only when the entire light array 1 emits light can the entire display module 4 be fully illuminated. Figure 2 In particular, the imaging concave mirror 5 is omitted.

[0028] In this embodiment, the LED array is used as the backlight source. Each LED is located on the light-entering side 25 of a conical light cup. The light-emitting side 26 of the conical light cup forms an emission surface. After passing through the diffuser 3, the light directly hits the TFT panel, forming image light D (e.g., Figure 3 Except for the diffuser 3, there are no optical elements (such as multiple reflectors, imaging concave mirrors, or convex lenses) between the light-emitting side 26 of the conical light cup and the light-entering side 41 of the display module 4 that can form a folded light path, convergence, or real image formation.

[0029] Please refer to Figure 3 , is a schematic diagram of the optical path of a backlight source used in a head-up display device. This embodiment further includes a windshield 6. An imaging concave mirror 5 reflects image light D projected by the display module 4 onto the windshield 6. The windshield 6 reflects the image light D, forming an image in the driver's eye box E. The display module 4 is positioned within the focal length of the imaging concave mirror 5. The equivalent distance of the light-emitting array 1 is greater than the focal length of the imaging concave mirror 5. The display module 4 forms a virtual image I outside the windshield 6, while the light-emitting array 1 forms a real image in the driver's eye box E inside the windshield 6.

[0030] Please refer to Figure 4 The diffuser 3 increases the uniformity of the backlight source L, but also increases the diffusion angle. Therefore, the display device of this embodiment further includes a convex lens array 7. The diffuser 3 is flat and disposed on the light-exiting side 32 of the diffuser 3. The convex lens array 7 is used to reduce the divergence angle of the horizontal plane light source diffused by the diffuser 3 and adjust it to the desired angle. The backlight source is then projected onto the rear (light-incident side 41) of the display module 4.

[0031] In this embodiment, the light incident side 71 of each convex lens of the convex lens array 7 is aligned with and covers the light outlet of a conical light cup 21 .

Claims

1. A backlight display device having a tapered light cup array, characterized in that: Include: a light array comprising a plurality of light sources, projecting a light; a conical light cup array comprising a plurality of conical light cups, each of which is tilted at a different angle and disposed on the light-emitting side of the light-emitting array, each of which corresponds to and sets the light-emitting angle of each light source; a diffuser, disposed on the light-emitting side of the conical light cup array, for increasing the uniformity of the light and forming a backlight source; a display module, displaying an image, disposed on the light-emitting side of the diffusion sheet, illuminated by the backlight source and emitting image light; An imaging concave mirror is disposed on the light-emitting side of the display module. The display module is located within the focal length of the imaging concave mirror so that the image is formed into a virtual image. The backlight source is located outside the focal length of the imaging concave mirror so that the backlight source is formed into a real backlight source image, i.e., a single eye box. Each of the light sources is configured to illuminate only a portion of the display module, and when all of the light sources emit light, the display module is fully illuminated. Wherein, the center normal line of each of the conical light cups intersects at the center position of the single eye box after the light path extends.

2. The backlight display device according to claim 1, wherein: The conical light cup is a hollow light cup with a reflective coating on its surface, or the conical light cup is a transparent solid light guide member in a cup shape.

3. The backlight display device according to claim 1, wherein Each of the conical light cups is a square cone, and the boundaries of the light outlets of two adjacent conical light cups are connected to each other. The light outlets of each conical light cup are aligned and located on the same plane to form a horizontal plane light source.

4. The backlight display device according to claim 1, wherein: The display module is a TFT panel.

5. The backlight display device according to claim 1, wherein: The diffusion sheet is in a flat plate shape.

6. The backlight display device according to claim 1, wherein: There is a gap between the light incident side of the diffusion sheet and the light emitting sides of the plurality of conical light cups.

7. The backlight display device according to claim 1, wherein: A convex lens array is further included between the light-emitting side of the diffusion sheet and the light-incident side of the display module, for converging the backlight source and then projecting it onto the display module.

8. The backlight display device according to claim 1, wherein: A windshield is further included between the optical path of the display module and the single eye box. The imaging concave mirror reflects the image light projected by the display module to the windshield, and the windshield reflects the image light to the single eye box.

9. The backlight display device according to claim 8, wherein: The display module is arranged within the focal length of the imaging concave mirror, the equivalent distance of the light emitting array is greater than the focal length of the imaging concave mirror, and the real image formed by the light emitting array is located within the windshield.

10. The backlight display device according to claim 1, wherein The light emitting array is an LED array.

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