Backlight display device with tapered light cup array

Abstract

The invention discloses a backlight display device with a conical light cup array, which comprises a plurality of luminous sources arranged in an array, a plurality of conical light cups arranged in an array, a diffusion sheet, a display module for displaying images and an imaging concave mirror, and the elements are sequentially arranged along a light path direction. The inclination angles of the conical light cups are different and correspond to the light-emitting sources one by one, and the conical light cups are used for setting the light-emitting angles of the light-emitting sources. Light of the luminous source forms a backlight source after passing through the diffusion sheet. The display module and the backlight source are respectively located inside and outside the focal length of the imaging concave mirror, and image light formed by lightening the image by the backlight source is projected to the single eye box by the imaging concave mirror. Each light emitting source lightens only a portion of the display module. And the extending light paths of the central normal lines of the conical light cups are intersected at the central position of the single eye box.

Description

Technical Field

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

[0002] The backlight display device is formed by lighting up the pixels of the display module (such as a TFT panel) through a light emitting module behind the display module, so that the image light source is directed forward and reaches the viewer's field of vision. The backlight provided by the light emitting module almost determines the quality of the image light source. Therefore, multiple optical elements are usually provided between the light source of the light emitting module and the display module to generate uniform light or to adjust the light intensity. Summary of the invention

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

[0004] To achieve the above-mentioned purpose, the present invention provides a backlight display device with 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 inclined at a different angle and is arranged 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 arranged 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 arranged on the light-emitting side of the diffuser to receive the backlight source and emit an image light. The imaging concave mirror is arranged on the light-emitting side of the display module, and 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 form a real image of the backlight source, that is, a single eye box. Each light source is constructed to light up only a portion of the display module, and when all the light sources emit light, the display module is fully lit. The center normal of each conical light cup intersects at the center position of a single eye box after the light path extends.

[0005] Preferably, the conical light cup is a hollow light cup with a reflective coating on the 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 borders 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 diffusion sheet is in a flat plate shape.

[0009] Preferably, 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.

[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 light 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.

[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 within 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 is a schematic diagram of another embodiment of a display device.

[0018] Explanation of the reference numerals: 0-aluminum flat 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 made with 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 of which is tilted at a different angle. The 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 coated with a high reflectivity coating, or a transparent solid light guide in the shape of a cup. The light inside the conical light cup 21 is totally reflected when projected onto the cup wall. The conical light cup array 2 is disposed on the light exit side of the light emitting array 1. The point light source of the LED is reflected in the conical light cup 21 and projected onto the light exit side 26. Each conical light cup 21 corresponds to a light source 11, so as to set the light exit angle of 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), and the boundaries of the light exits of adjacent conical light cups 21 are connected to each other.

[0024] The light incident side 31 of the diffuser 3 is aligned with the light emitting side 26 of the conical light cup 21 to increase the uniform light intensity of the backlight source. There is a gap between the light incident side 31 of the diffuser 3 and the light emitting side 26 of the conical light cup 21, that is, the diffuser 3 is not completely attached to the light emitting side 26 of the conical light cup 21, so as to prevent the black shadow generated by the boundary 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] The 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 to form an image into a virtual image I. The backlight source is located outside the focal length of the imaging concave mirror 5, so that the light of the backlight source is reflected by the imaging concave mirror 5 to form a real image of the backlight source, that is, a single eye box E.

[0027] Figure 2Schematic diagram of applying a backlight module to a display device. The conical light cup array 2 is composed of a plurality of conical light cups 21 with individual tilts. The light outlets of each conical light cup 21 are aligned and located on the same plane, so that the entire light outlet side 26 provides a horizontal light source. The light outlet side 26 of the conical light cup 21, the diffuser 3, and the light entrance side 41 of the display module 4 are all arranged at intervals and parallel to each other. The center normal F of each conical light cup 21 intersects at the center of a single eye box E after the light path extends. Each light source 11 only illuminates a part of the display module 4. The entire display module 4 can only be fully illuminated when the light array 1 emits all light. Figure 2 In particular, the imaging concave mirror 5 is omitted.

[0028] In this embodiment, the LED array is used as a 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 to form an image light D (such as Figure 3 Except for the diffuser 3, there is no optical element (such as multiple reflectors, imaging concave mirrors or convex lenses) between the light exit side 26 of the conical light cup and the light entrance side 41 of the display module 4 that can form a folded light path, generate convergence, or form a real image.

[0029] Please refer to Figure 3 , is a schematic diagram of the optical path of a backlight source applied to a head-up display device. In this embodiment, a windshield 6 is further included, and the imaging concave mirror 5 reflects the image light D projected by the display module 4 to the windshield 6, and the windshield 6 reflects the image light D to form an image in a driver's eye box E, the display module 4 is arranged 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 an image virtual image I outside the windshield 6, and the light emitting array 1 forms a real image eye box E inside the windshield 6.

[0030] Please refer to Figure 4 , the diffuser 3 will increase the uniformity of the backlight source L, but the diffusion angle will increase. Therefore, the display device of this embodiment further includes a convex lens array 7, the diffuser 3 is in a flat plate shape, and the convex lens array 7 is arranged on the light exit 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 required angle. Then, the backlight source is projected to the rear of the display module 4 (the light entrance side 41).

[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 conical light cup array, characterized in that: Include: A light array, comprising a plurality of light sources, projects a light; A conical light cup array, comprising a plurality of conical light cups, each of which is inclined at a different angle and is disposed on the light-emitting side of the light-emitting array, and each of which corresponds to and sets the light-emitting angle of each of the light sources; 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, which displays an image, is disposed on the light-emitting side of the diffusion sheet, is illuminated by the backlight source and emits an 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 to form a virtual image of the image. The backlight source is located outside the focal length of the imaging concave mirror to form a real backlight source image, that is, 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 optical cups intersects at the center position of the single eye box after the optical path is extended.

2. The backlight display device according to claim 1, wherein: The conical light cup is a hollow light cup with a reflective coating on the 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, the borders of the light outlets of two 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.

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 the shape of a flat plate.

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 also included between the light-emitting side of the diffusion sheet and the light-incoming 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 also 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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