Background
In recent years, 3D display has been rapidly developed, and screens for 3D display are also getting larger, and when the screens for 3D display are large screens (for example, screens of 21 inch, 34 inch, and even larger sizes), problems of low definition and low brightness on both sides of the screens may occur.
As shown in fig. 1, which is a schematic diagram of a positional relationship between a display device and human eyes of a 3D display in the related art, fig. 1 is a view of a display device 11 and human eyes 13 of a user from a top view. The screen of the display device 11 is a flat screen, the eyeball of the human eye 13 of the user is similar to a convex lens, and the display light E emitted by the display device 11 penetrates through the human eye 13 of the user and is on the retina-shaped imaging plane 15. When display device 11's screen is the large screen, user's eyes 13 focus is aimed at display device 11's central point puts and does not do the focus adjustment, then display light E sees through user's eyes 13, and focus focal plane 17 that forms is the curved surface, display device 11 central area send display light E focus with focal plane 17's center, display device 11 left and right sides send light E focus in focal plane 17's both sides, focal plane 17's central point with the central point coincidence of image plane 15, focal plane 17's both sides with image plane 15's both sides are kept away from, and at this moment, the phenomenon that user's eyes 13 observed is for display device 11's central area shows clearly, and display device 11 left and right sides area shows the blur.
As shown in fig. 2, which is a schematic diagram of the display device shown in fig. 1, the display device 11 includes a display plane 111 and a 3D grating 113, the 3D grating 113 includes a grating unit 113A, the grating unit 113A is a convex lens (for example, CN102436069a and CN 211293321U-pillar lens grating), a display light ray E emitted by the display plane 111 passes through the grating unit 113A to form a main optical axis 113B, directions of the main optical axes 113B formed after passing through different grating units 113A are the same, when a propagation direction of the main optical axis 113B corresponding to a central region of the display plane 111 is toward the user's eye 13, propagation directions of the main optical axes 113B corresponding to two side regions of the display plane 111 may deviate from the user's eye 13, and a phenomenon observed by the user's eye 13 is that display brightness of the central region of the display device 11 is high, and display brightness of the two side regions of the display device 11 is low.
Therefore, it is necessary to provide a 3D display device with high definition and uniform brightness to solve the above technical problems.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely below, and it should be apparent that the described embodiments are only some embodiments of the present invention, but not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
First embodiment
Please refer to fig. 3, which is a schematic view of a display device and human eyes of a user according to the present invention, the display device 20 includes a display screen 21 and an optical composite film 22, wherein the display device 20 is a naked-eye 3D display device, and the display screen 21 is used for a 3D image to be displayed and emitting a target light E corresponding to the displayed 3D image. The position of the human eyes 27 of the user is taken as a preset viewpoint, and the preset viewpoint is the position with the best definition effect and brightness uniformity effect when the user watches the display device 20. (for example, the position of the display screen 20 at a vertical distance of 40cm from the center of the display screen 21 is the preset viewpoint, and the best visual effect is obtained when the human eyes 27 of the user are at the preset viewpoint.)
The human eye 27 of the user faces the center of the display screen 21, and fig. 1 is a schematic view of the display device 21 and the human eye 27 of the user from a top view.
The optical composite film 22 includes a 3D grating 23, a filling medium 24 and a light guide plate 25, the light guide plate 25 is disposed between the display screen 21 and the 3D grating 23, and the filling medium 24 is used for filling a gap between the 3D grating 23 and the light guide plate 25.
Referring to fig. 4, which is a schematic view of the display screen structure shown in fig. 3, the display screen 21 is a flat screen with a height h and a width w.
Fig. 5 is a schematic view of a three-dimensional structure of the 3D grating shown in fig. 3. The 3D grating 23 includes semi-cylindrical grating units 231 arranged in an array, and in this embodiment, the grating units 31 are arranged in a direction parallel to the height h of the display screen 21. In other embodiments, the grating unit 231 may also be disposed obliquely along the direction of the height h of the display screen 21.
Referring to fig. 6, which is a schematic view of a three-dimensional structure of the light guide plate shown in fig. 3, the light guide plate 25 includes light guide units 251 arranged in an array, the light guide units 251 and the grating units 231 are arranged in association, when the grating units 231 are arranged along a direction parallel to the height h of the display screen 21, correspondingly, the light guide units 251 are also arranged along a direction parallel to the height h of the display screen 21. The grating units 231 and the light guide units 251 are arranged in parallel, and one grating unit 231 corresponds to one light guide unit 251. In other embodiments, a plurality of the grating units 231 may correspond to one of the light guide units 251, for example, two, three, or four or even more grating units 231 correspond to one of the light guide units 251, which is not limited in particular. The light guide unit 251 is a quadrangular prism or a triangular prism, and the cross section of the quadrangular prism is trapezoidal.
Please refer to fig. 7a and 7b in combination, wherein fig. 7a is a schematic cross-sectional view of the light guide unit shown in fig. 3, and fig. 7b is a schematic cross-sectional view of the light guide unit disclosed in the present invention.
As shown in fig. 7a, in the present embodiment, the light guide unit 251 is a quadrangular prism, and the cross section of the light guide unit 251 is a right trapezoid. In other embodiments, the cross section of the light guide unit 251 may also be a triangle or a trapezoid, as shown in fig. 7b, the cross section of the light guide unit 251 may also be an acute triangle 252, a right triangle 253, an isosceles trapezoid 254, or a general trapezoid 255.
Please refer to fig. 3, fig. 7a and fig. 9 in combination, wherein fig. 9 is a schematic diagram illustrating a relationship between a cross section of the light guide unit shown in fig. 3 and a target light ray.
The light guide unit 251 includes a light incident surface 251A and a light emitting surface 251B, which are disposed opposite to each other, and the light incident surface 251A is connected to the light emitting surface 251B through a connecting surface. The target light ray E enters the light guide unit 251 through the light incident surface 251A, and exits the light guide unit 251 through the light exiting surface 251B after propagating in the light guide unit 251. The light guide unit 251 refracts the target light ray E sequentially passing through the light incident surface 251A and the light emitting surface 251B, so as to change the propagation direction of the target light ray E.
An angle formed by the direction in which the target light ray E enters the light incident surface 251A and the direction in which the target light ray E exits the light emitting surface 251B is a target deflection angle. As shown in fig. 3 and 9, E' is a propagation direction of the object light ray E before entering the light incident surface 251A.
In order to enable a user to obtain a better visual check, the target deflection angle is determined according to the position relationship between the human eyes 27 of the user and the display screen 21, and the degrees of the target deflection angles corresponding to different areas in the display screen 21 are different. For example, as shown in fig. 4, the display screen 21 is divided into different regions, including a region i, a region ii, a region iii, a region iv, and a region v, which are sequentially arranged from left to right. If the human eye 27 of the user faces the center position of the area iii, the target light E corresponding to the area i and the area ii deflects rightward, and the degree of the target deflection angle of the target light E in the area i is greater than the degree of the target deflection angle of the target light E in the area ii. The target light ray E corresponding to the region IV and the region V deflects leftwards, and the degree of the target deflection angle of the target light ray E in the region V is greater than that of the target deflection angle of the target light ray E in the region IV. The degree of the target deflection angle of the target light ray E in the region iii is zero. It should be noted that, the target deflection angles of the target light rays E corresponding to the regions may be the same or different, and when the target deflection angles of the target light rays E corresponding to the regions I are the same, in the regions I, the relationship between the light guide unit 251 and the grating unit 231 may be set such that a plurality of grating units 231 correspond to one light guide unit 251.
In other embodiments, the display screen 21 is not limited to be divided into five regions, and the display screen 21 may be divided into 6, 7, 8 or other number of regions according to actual requirements, and of course, each of the grating units 231 or the display screen 21 corresponding to the light guide unit 251 may also be divided into one region according to the number of the grating units 231 or the light guide units 251, and each region corresponds to a different degree of the target deflection angle.
Please refer to fig. 8, which is a schematic diagram illustrating the relationship between the target deflection angle and the eyes of the user shown in fig. 3. Next, referring to fig. 8, the determination of the target deflection angle will be described by taking an example in which the display screen 21 corresponding to each light guide unit 251 is divided into one area.
The target deflection angle is:
where θ is the target deflection angle, z is a vertical distance from the preset viewpoint to the display screen 21, x is a vertical distance from a point O to the light guide unit 251, and the point O is an intersection point between a perpendicular line from the preset viewpoint to the display screen 21 and the display screen 21. In this embodiment, the human eyes 27 of the user are located at the position of the preset viewpoint, so z is the vertical distance from the human eyes 27 of the user to the display screen 21, and the point O is the intersection point between the vertical line from the human eyes 27 of the user to the display screen 21 and the display screen 21.
Referring to fig. 9, in the light guide unit 251, a plane where the light incident surface 251A is located and a plane where the light emitting surface 251B is located form a target included angle. The degree of the target deflection angle is adjusted by adjusting the target included angle and the refractive index of the light guide unit 251. The refractive index of the light guide unit 251 is adjusted by selecting different materials.
The target angle is described below with reference to fig. 9.
The target included angle is as follows:
α=arcsin(n×sinθ)
where α is the target included angle, and n is the refractive index of the light guide unit 251.
According to the above formula, in the same light guide plate 25, the degree of the target deflection angle of the target light E corresponding to different display screens 21 can be determined according to the size of the display screen 21 and the preset viewpoint of preset adjustment, and then the degree of the target included angle of different light guide units 251 in the same light guide plate 25 can be determined according to the degree of the target deflection angle and the refractive index of the material of the light guide unit 251, so as to process the light guide plate 25 according to the degree of the target included angle.
In this embodiment, the degrees of the target included angles of the different light guide units 251 in the same light guide plate 25 are different, so that the target light rays E corresponding to different regions of the display screen 21 have the target deflection angles with different degrees, so as to adjust the propagation directions of the main optical axes generated by the different grating units 231 to be directed to the human eyes 27 of the user, thereby improving the brightness of the two sides of the display screen 21 at the angle observed by the human eyes 27 of the user, and making the brightness of the display screen 21 uniform. Meanwhile, due to the deflection of the propagation direction of the target light ray E, the target light ray E is made to penetrate through the human eyes 27 of the user and then is focused on the same image plane 29, the image plane 29 is located in the same plane, so that a compensation virtual image 28 corresponding to the image plane 29 is formed, and the compensation virtual image 28 is a curved surface and is virtual image compensation of an image displayed on the display screen 21. The user's eyes 27 are similar to the convex lens, because the compensation virtual image 28 is a curved surface, the image plane 29 is a plane, so that the compensation of the curvature of field of the convex lens is realized, and then the user's eyes 27 are right opposite to the center of the display screen 21, and when the user's eyes 27 do not carry out focal length adjustment, under the visual angle of the user's eyes 27, the image display of each region of the display screen 21 is a clear state.
Compared with the prior art, the utility model provides an optical composite film 22 with in the display device 20, through light guide plate 25 is right target light E refracts, changes target light E's direction of propagation, so that target light E's direction of propagation orientation predetermine the sight point, be in when user's eyes when predetermineeing the sight point, after the refraction target light E sees through user's eyes 27 focus on in image plane 29, and then form the image plane corresponds compensation virtual image 28. When the user eyes 27 do not adjust the focal length and do not move the position, the display screen 21 achieves the display effect of uniform brightness and clear display under the visual angle of the user eyes 27, and the user experience of large-screen 3D display is improved.
Second embodiment
Please refer to fig. 11, which is a schematic structural diagram of another display device according to an embodiment of the present invention. The display device 30 includes a display screen 31 and an optical composite film 32, where the optical composite film 32 includes a 3D grating 33, a filling medium 34 and a light guide plate 35, where the filling medium 34 is used to fill a gap between the 3D grating 33 and the light guide plate 55. In this embodiment, the display screen 31, the 3D grating 33 and the light guide plate 35 are substantially the same as those of the first embodiment, except that the 3D grating 33 is disposed between the display screen 31 and the light guide plate 35.
To those skilled in the art, the grating unit and the light guide unit associated set in the present invention means in the first embodiment that the grating unit and the light guide unit are arranged in parallel, and one of the grating unit corresponds to one of the light guide unit, in other embodiments, the grating unit and the light guide unit associated set may also be two, three or four or more of the light guide unit corresponds to one of the grating unit, as long as the light guide unit can guide the target light E to the preset viewpoint.
The above only is the partial embodiment of the present invention, not therefore the limitation of the patent scope of the present invention, all the equivalent structures or equivalent flow changes made by the contents of the specification and the drawings, or directly or indirectly applied to other related technical fields, are included in the patent protection scope of the present invention.