BACKLIT DISPLAY DEVICE WITH TAPERED REFLECTIVE CUP ARRAY - Patent application

Abstract

To provide a display device with a backlight including a tapered reflecting cup array.SOLUTION: A display device with a backlight has a plurality of light sources, a plurality of tapered cups 21 arranged in an array shape, a diffuser 3, a display module 4 that displays an image, and an image concave mirror 5, which are arranged continuously along an optical path. The tapered cups are inclined at different angles and each define an emission angle in correspondence with one light source. Light from the light sources passes through the diffuser to form backlight. The display module and the backlight are arranged inside a focal point of the image concave mirror and outside the focal point, respectively. The backlight illuminates image light to form an image, and the image light is reflected by the image concave mirror and subsequently projected on a single eye box. The light sources illuminate part of the display module. A center normal of each tapered cup intersects the center of the single eye box.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a backlit display device, and more particularly to a backlit display device with a tapered reflector cup array. [Background technology]

[0002] Imaging of a backlit display device can involve illuminating the pixels of a display module (such as a TFT panel) through a light source module behind the display module, and projecting the image light forward to reach the viewer's field of view. The backlight provided by the light source module largely determines the quality of the image light. Therefore, the light from the light source module and the display module is usually provided to multiple optical elements between the light source module and the display module to form a uniform light or adjust the light intensity. Summary of the Invention [Means for solving the problem]

[0003] The present invention relates to a backlit display device comprising a light source array, a tapered cup array, a diffuser, a display module, and a tapered reflective cup array containing an imaging concave mirror. The light source array includes a plurality of light sources that project light. A tapered cup array is provided with a plurality of tapered cups. The light source array has a light output surface side on which tapered cups are arranged with different inclination angles, and each tapered cup corresponds to a light source, respectively, to define the output angle of the light source. The diffuser is arranged on the light output surface side of the tapered cup array to improve the uniformity of the light and form a backlight. A display module for displaying an image is disposed on the light exit surface side of the diffuser that receives the backlight. The backlight illuminates an image to form image light. The imaging concave mirror is disposed on the light-emitting side of the display module. The display module and the backlight are disposed within and outside the focal distance of the imaging concave mirror, respectively, to form a virtual image and a backlight real image, i.e., a single eyebox. Each light source illuminates a part of the display module, and the display module is fully illuminated when all the light sources emit light simultaneously. The center of each tapered cup light The line intersects the center of a single eyebox along the extended optical path.

[0004] In some embodiments, the tapered cup is a hollow cup with a reflective coating on its surface, or a cup-shaped transparent solid light guide.

[0005] In some embodiments, each tapered cup is a square frustum. The cup edges of the light outlets of two adjacent tapered cups are connected to each other. The light outlets of each tapered cup are aligned and positioned on the same horizontal plane to form a horizontal light source.

[0006] In some embodiments, the display module is a TFT (thin film transistor) panel.

[0007] In some embodiments, the diffuser has a flat, plate-like shape.

[0008] In some embodiments, the light input side of the diffuser is isolated from the light output side of the tapered cup.

[0009] In some embodiments, a convex lens array is provided between the light output side of the diffuser and the light input side of the display module to focus the backlight and project the light onto the display module.

[0010] In some embodiments, the display module and the single eyebox are provided with a windshield between the display module and the single eyebox on the optical path. The image concave mirror reflects the image light projected from the display module to the windshield, which then reflects the image light to a single eyebox.

[0011] In some embodiments, the display module is located within the focal length of the imaging concave mirror, and the equivalent distance of the light source array is longer than the focal length of the imaging concave mirror. The array of light sources forms a real image within the windshield.

[0012] In some embodiments, the light source array is an LED array. [Brief description of the drawings]

[0013] [Figure 1] 1 is a schematic diagram of a tapered cup according to some embodiments of the present invention. [Diagram 2] 1 is a schematic diagram of the structure and light paths of a display device. [Diagram 3] 1 is a schematic diagram of the structure and optical paths of a head-up display device. [Figure 4] 1 is a schematic diagram of a display device according to some embodiments of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] In the following description, the light emission direction of the light source array 1 is assumed to be the front, in accordance with common understanding among those skilled in the art.

[0015] The following description will be given with reference to FIGS. The backlit display device according to an embodiment of the present invention includes a light source array 1 , a tapered cup array 2 , a diffuser 3 , a display module 4 , and an image concave mirror 5 .

[0016] The light source array 1 is configured to provide backlighting. The light source array 1 is provided with a plurality of light sources 11, and is, for example, an LED array disposed on an aluminum substrate 0.

[0017] The tapered cup array 2 is provided with a plurality of tapered cups 21 . Each tapered cup 21 is inclined at a different angle and defines a light input side 25 and a light output side 26 . Each light source 11 (LED) is disposed corresponding to the light incident surface side 25 of the tapered cup 21 . Tapered cup 21 may be a hollow cup with a highly reflective coating on its surface, or a cup-shaped transparent solid light guide. The tapered cup 21 is designed so that when light hits the cup wall, the light is totally reflected inside the cup. The tapered cup array 2 is disposed on the light emission surface side 26 of the light source array 1 . The LED point light source is reflected inside the tapered cup 21 and projected onto the light exit surface side 26. Each tapered cup 21 corresponds to a respective light source 11 and defines the emission angle of each light source 11 .

[0018] In some embodiments, as illustrated in FIG. 1, each tapered cup 21 of the tapered cup array 2 presents a square frustum with a square light input side 25 (light inlet) and a square light output side 26 (light outlet). The cup edges on the light outlet side of two adjacent tapered cups 21 are connected to each other.

[0019] The diffuser 3 has a light entrance surface 31 facing the light exit surface 26 of the tapered cup 21 in order to improve the uniformity of the backlight. The light input side 31 of the diffuser 3 is separated from the light output side 26 of the tapered cup 21 . That is, in order to prevent a black shadow occurring at the boundary of the tapered cup 21 from being projected forward, the diffuser 3 is not completely attached to the light exit surface side 26 of the tapered cup 21 .

[0020] The display module is a TFT panel that displays images. The display module 4 has a light incident surface 41 that receives light from the backlight and forms image light D, and is provided facing the light exit surface 32 of the diffuser 3 .

[0021] The image concave mirror 5 is disposed on the light exit surface side 42 of the display module 4 . The display module 4 is positioned within the focal length of the image concave mirror 5 to form a virtual image I. The backlight is positioned outside the focal length of the imaging concave mirror 5 . The image concave mirror 5 reflects the light from the backlight to form a backlight real image. of Single Eye Box E To Form.

[0022] Reference is now made to FIG. 2, which is a schematic diagram of a backlight module applied to a display device. The tapered cup array 2 is provided with a number of tapered cups 21 inclined at different angles. The light outlets of each tapered cup 21 are aligned and positioned on the same horizontal plane, such that the light exit side 26 forms a horizontal light source. The light exit surface side 26 of the tapered cup 21, the diffuser 3, and the light entrance surface side 41 of the display module 4 are arranged parallel to and spaced apart from each other. The center of each tapered cup 21 light Line F intersects the center of a single eyebox E along the extended optical path. Each light source 11 illuminates a part of the display module 4, and the display module 4 is fully illuminated when all the light sources 11 of the light source array 1 emit light simultaneously. Here, in FIG. 2, the image concave mirror 5 is not shown.

[0023] In some embodiments, the LED array functions as a backlight. Each LED is disposed on the light incident surface side 25 of the tapered cup 21 . The tapered cup 21 is provided with a light exit side 26 forming a light exit surface, from which light passes through a diffuser 3 and is then projected onto a TFT panel to form image light D (see FIG. 3). Except for the diffuser 3, there are no other optical elements (e.g., reflectors, image concave mirrors, or convex lenses) positioned between the light exit side 26 of the tapered cup 21 and the light entrance side 41 of the display module 4 to form a curved optical path, to focus light, or to form a real image.

[0024] Reference will now be made to FIG. 3, which is a schematic diagram of a backlight module applied on the optical path of a head-up display device. In some embodiments, a windshield 6 is included. The image concave mirror 5 reflects the image light D projected from the display module 4 to the windshield 6, which then reflects the image light D to form an image in the driver's eyebox E. The display module 4 is positioned within the focal length of the imaging concave mirror 5 . The equivalent distance of the light source array 1 is greater than the focal length of the imaging concave mirror 5 . The display module 4 forms a virtual image I on the outside of the windshield. The light source array 1 forms a real image eyebox E inside the windshield.

[0025] The following description will be given with reference to FIG. The diffuser 3 improves the uniformity of the backlight L, resulting in an increased diffusion angle. For this purpose, the display device is further provided with a convex lens array 7 . The diffuser 3 has a flat plate shape, and the convex lens array 7 is disposed on the light exit surface side 32 of the diffuser 3 . The convex lens array 7 narrows the divergence angle of the horizontal light source diffused by the diffuser 3, adjusts it to a desired angle, and projects the backlight onto the rear of the display module 4 (on the light incident surface 41 side).

[0026] In some embodiments, the convex lens array 7 is provided with convex lenses. Each convex lens faces the light outlet of the tapered cup 21 and covers the tapered cup 21 .

Claims

1. 1. A backlit display device comprising a tapered reflector cup array, comprising: a light source array including a plurality of light sources for projecting light; A tapered cup array having a plurality of tapered cups, characterized in that each tapered cup is arranged on a light output surface side of the light source array, the tapered cups being inclined at different angles, and each tapered cup corresponds to each light source, respectively, and defines an output angle of the light source; and a diffuser disposed on a light output side of the tapered cup array to provide uniformity of the light to form a backlight; a display module that displays an image and is disposed on a light exit surface side of the diffuser, the display module being characterized in that the backlight illuminates the image to form image light; an imaging concave mirror disposed on the light exit surface side of the display module, the display module being disposed within a focal length of the imaging concave mirror and forming a virtual image, the backlight being disposed outside the focal length of the imaging concave mirror and forming a backlight real image in a single eyebox corresponding to a real image of a light source array, each light source illuminating a portion of the display module, the display module being fully illuminated when all light sources emit the light simultaneously, and a central light ray of each tapered cup intersects with a center of the single eyebox along an extended light path; A backlit display device.

2. 2. The backlit display device of claim 1, wherein the tapered cup is a hollow cup having a reflective coating on its surface, or a cup-shaped transparent solid light guide.

3. 2. The backlit display device of claim 1, wherein each tapered cup is characterized by being a square frustum, the cup edges of the light outlets of two adjacent tapered cups are connected to each other, and the light outlets of each tapered cup are aligned and disposed on the same horizontal plane to form a horizontal light source.

4. 2. The backlit display device of claim 1, wherein the display module is a TFT (thin film transistor) panel.

5. 2. The backlit display device of claim 1, wherein the diffuser has a flat plate shape.

6. 2. The backlit display device of claim 1, wherein a light input side of the diffuser is separated from the light output side of the tapered cup.

7. 2. The backlit display device of claim 1, further comprising a convex lens array disposed between the light exit surface of the diffuser and the light entrance surface of the display module to concentrate the backlight and project the light onto the display module.

8. 2. The backlit display device of claim 1, wherein the display module and the single eyebox are provided with a windshield between the display module and the single eyebox on the optical path, the image concave mirror reflects the image light projected from the display module to the windshield, and then the windshield reflects the image light to the single eyebox.

9. 9. The backlit display device of claim 8, wherein the display module is disposed within the focal length of the image concave mirror, the equivalent distance of the light source array is longer than the focal length of the image concave mirror, and the light source array forms a real image in the space inside the windshield.

10. 2. The backlit display device of claim 1, wherein the light source array is an LED array.

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