Image display apparatus

Abstract

The invention provides an image display apparatus. The image display apparatus includes a plurality of microlens groups and an imaging device. And the micro lens groups are arranged in an array form. The micro-lens group receives the display image and generates a plurality of image light beams, and the advancing directions of the image light beams are not parallel to each other. The imaging device receives the image light beams, focuses the image light beams to respectively generate a plurality of image light beams, and projects the image light beams to a target area, so that each image light beam is imaged in the target area.

Description

Technical Field

[0001] The present invention relates to an image display device, and in particular to an image display device capable of improving the visual field of an output image. Background Art

[0002] In the field of augmented reality (AR), fixed image depth optical designs are often used, such as waveguide and birdbath architectures. The birdbath architecture uses geometric optics to achieve a large field of view and excellent image resolution, but its optical efficiency and overall thinness are limited by the optical architecture. Although the waveguide architecture can realize thin glasses-type augmented reality products, its field of view is limited by the theoretical upper limit of the refractive index of the selected substrate. At the same time, due to the characteristics of the fixed image focal plane of the above two architectures, users will feel uncomfortable due to the phenomenon of Vergence Accommodation Conflict (VAC).

[0003] Retinal projection augmented reality devices can overcome the discomfort caused by the above-mentioned visual convergence and accommodation conflict phenomenon. In retinal projection design, holographic optical elements (HOE) are mostly used. Through holographic optical elements, the characteristics of optical components can be recorded to obtain images with a large field of view. However, since holographic optical elements are diffraction elements, they are quite sensitive to the wavelength of incident light, so this type of solution is mostly used only in applications with monochromatic light sources. Summary of the invention

[0004] The present invention is directed to an image (picture) display device, which can improve the visual field of the output image.

[0005] According to an embodiment of the present invention, an image display device includes a plurality of microlens groups and an imaging device. The microlens groups are arranged in an array. The microlens groups receive display images and respectively generate a plurality of image beams, and the directions of travel of the image beams are not parallel to each other. The imaging device receives the image beams, focuses the image beams to respectively generate a plurality of image beams, and projects the image beams to a target area so that each image beam forms an image in the target area.

[0006] Based on the above, the image display device of the present invention generates multiple image light beams with non-parallel traveling directions through a microlens group, thereby expanding the field of view (FOV) of the output image, avoiding the dispersion phenomenon caused by the holographic optical component, and improving the image quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 A schematic diagram of an image display device according to an embodiment of the present invention;

[0008] Figure 2 A schematic diagram of an output image generated by an image display device according to an embodiment of the present invention;

[0009] Figure 3 A schematic diagram of an image display device according to another embodiment of the present invention;

[0010] Figure 4 FIG. 4 is a schematic diagram of a three-dimensional structure of an image display device according to another embodiment of the present invention. DETAILED DESCRIPTION

[0011] Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals are used in the drawings and the description to refer to the same or like parts.

[0012] Please refer to Figure 1 , Figure 1 A schematic diagram of an image display device according to an embodiment of the present invention is shown. The image display device 100 includes an image projector 130, a plurality of microlens groups 111-113, and an imaging device 120. The image display device 100 can be applied to a virtual reality (VR) display, an augmented reality (AR) display, and a mixed reality (MR) display. The microlens groups 111-113 and the imaging device 120 can be configured along the same optical axis. The microlens groups 111-113 are arranged in an array. The microlens groups 111-113 can be used to receive a display image DIM emitted by the image projector 130, wherein the display image DIM can be distinguished into a plurality of output sub-images SDIM1-SDIM3 according to a display position, and the microlens groups 111-113 are respectively used to receive the output sub-images SDIM1-SDIM3, and collimate the output sub-images SDIM1-SDIM3 to generate a plurality of image beams IB1, IB2, and IB3, respectively. It is worth noting that in this embodiment, the traveling directions of the image beams IB1, IB2 and IB3 are not parallel to each other. In addition, the multiple image sub-beams that may be included in each of the image beams IB1, IB2 and IB3 are parallel to each other. For example, in the image beam IB1, the image sub-beams IB1_1, IB1_2 and IB1_3 are parallel to each other.

[0013] In addition, the imaging device 120 is used to receive the image beams IB1-IB3, and to focus the received image beams IB1-IB3 to generate a plurality of image beams VIB1-VIB3 respectively. The imaging device 120 is also used to project the image beams VIB1-VIB3 to a target area, and to image the image beams VIB1-VIB3 in the target area, and to generate a plurality of imaging points IP1-IP3 respectively, wherein the target area corresponds to the position of the user's eyeball EYE.

[0014] In the present embodiment, the imaging device 120 includes a lens group 121 and a beam splitter 122. The lens group 121 is disposed between the micro lens group 111-113 and the beam splitter 122. The micro lens group 111-113 is a focusing lens group, which is used to collimate the image beams IB1-IB3, and focus the image beams IB1-IB3 through the lens group 121 to generate focused image beams VIB1-VIB3 respectively. The lens group 121 sends the focused image beams VIB1-VIB3 to a reflection surface RF1 of the beam splitter 122. The reflection surface RF1 of the beam splitter 122 receives the image beams VIB1-VIB3, and reflects the image beams VIB1-VIB3 to the target area, so that the image beams VIB1-VIB3 can generate a plurality of imaging points IP1-IP3 on the user's eyeball EYE.

[0015] Please note that in this embodiment, the image beams IB1 to IB3 correspond to the multiple sub-images SDIM1 to SDIM3 of the display image DIM, and the focused image beams VIB1 to VIB3 correspond to the image beams IB1 to IB3. Therefore, the imaging points IP1 to IP3 generated by the image beams VIB1 to VIB3 can be the multiple output sub-images corresponding to the sub-images SDIM1 to SDIM3. Figure 2 The schematic diagram of the output image generated by the image display device of the embodiment of the present invention is shown. The output image 200 generated by the image display device 100 can be composed of a plurality of output sub-images 210-230. The output sub-images 210-230 can correspond to the imaging points IP1-IP3 generated by the image beams VIB1-VIB3 respectively.

[0016] It can be seen from the above description that by splicing multiple output sub-images 210-230 to generate the output image 200, the image display device 100 of the embodiment of the present invention can effectively expand the image field of the output image 200 and effectively improve the image quality.

[0017] Furthermore, under the premise that the image field of the output image 200 is effectively expanded, when the user rotates the eyeball, there will be no image loss due to the imaging point not falling in the pupil.

[0018] Incidentally, in Figure 1 In the embodiment, the lens group 121 may include one or more lenses. The lens group 121 may include at least one focusing lens, such as a biconvex lens, a concave-convex lens, a convex-planar lens, or a plano-convex lens. The beam splitter 122 may be a plane mirror. The reflection angle of the image light beams VIB1-VIB3 provided by the beam splitter 122 may be set according to the relative position relationship between the user's eyeball EYE and the incident direction of the image light beams VIB1-VIB3, without any specific restrictions.

[0019] Please refer to Figure 3 , Figure 3 A schematic diagram of an image display device according to another embodiment of the present invention is shown. The image display device 300 includes an image projector 330, a plurality of microlens groups 311-313, and an imaging device 320. The microlens groups 311-313 and the imaging device 320 can be configured along the same optical axis. The microlens groups 311-313 are arranged in an array. The microlens groups 311-313 can be used to receive a display image DIM, wherein the display image DIM can be divided into a plurality of output sub-images SDIM1-SDIM3 according to a display position, and the microlens groups 311-313 are used to receive the output sub-images SDIM1-SDIM3 respectively, and collimate the output sub-images SDIM1-SDIM3 to generate a plurality of image beams IB1, IB2, and IB3 respectively. It is worth noting that in the present embodiment, the traveling directions of the image beams IB1, IB2, and IB3 are not parallel to each other.

[0020] In this embodiment, the image projector 330 is used to emit the display image DIM, wherein the image projector 330 can be any type of projector, such as a laser scanning projector.

[0021] In addition, the imaging device 320 is used to receive the image beams IB1-IB3, and to focus the received image beams IB1-IB3 to generate a plurality of focused image beams VIB1-VIB3. The imaging device 320 is also used to project the image beams VIB1-VIB3 to a target area, and to image the image beams VIB1-VIB3 in the target area, and to generate a plurality of imaging points IP1-IP3, wherein the target area corresponds to the position of the user's eyeball EYE.

[0022] In the present embodiment, the imaging device 320 includes a focusing mirror 321 and a beam splitter 322. The beam splitter 322 can receive the image light beams IB1-IB3, and respectively generate a plurality of first light beams AIB1-AIB3 by reflecting the image light beams IB1-IB3. The beam splitter 322 also emits the plurality of first light beams AIB1-AIB3 to the reflecting surface of the focusing mirror 321. The focusing mirror 321 receives the first light beams AIB1-AIB3, and respectively generates a plurality of image light beams VIB1-VIB3 by reflecting and focusing the first light beams AIB1-AIB3, and then projects the image light beams VIB1-VIB3 to the beam splitter 322. In the present embodiment, the focusing mirror 321 can be a concave mirror.

[0023] In addition, the image light beams VIB1-VIB3 can be transmitted through the beam splitter 322 and transmitted to the target area where the user's eyeball EYE is located. The image light beams VIB1-VIB3 can form a plurality of imaging points IP1-IP3 on the eyeball EYE. The imaging points IP1-IP3 correspond to a plurality of partitioned images of the display image DIM, and are used to generate a plurality of output sub-images. The plurality of output sub-images can be spliced ​​into a complete output image. Furthermore, under the premise that the image field of the output image is effectively expanded, when the user rotates the eyeball, there will be no image loss due to the imaging point not falling in the pupil.

[0024] Please refer to the following Figure 4 , Figure 4 A schematic diagram of a three-dimensional structure of an image display device according to another embodiment of the present invention is shown. The image display device 400 includes an image projector 430, a plurality of microlens groups ML11 to ML33, a beam splitter 422, and a focusing mirror 421. The microlens groups ML11 to ML33 are disposed on an XZ plane and are arranged in an array. The microlens groups ML11 to ML33 receive a display image DIM emitted along the Y-axis direction, and respectively generate a plurality of image light beams. Please note that in this embodiment, the characteristics of the image light beams generated by the microlens groups ML11 to ML33 are the same as the characteristics of the image light beams IB1 to IB3 in the aforementioned embodiment, and will not be elaborated on herein.

[0025] Where X, Y, and Z are the three axes of a Cartesian coordinate system.

[0026] The beam splitter 422 and the focusing mirror 421 constitute an imaging device. In this embodiment, the microlens group ML11-ML33 and the beam splitter 422 are arranged along the optical axis of the display image DIM, and the beam splitter 422 is arranged between the focusing mirror 421 and the microlens group ML11-ML33. In this embodiment, the beam splitter 422 and the focusing mirror 421 generate imaging points in the same manner as in the present embodiment. Figure 3 In the embodiment of the present invention, the method of generating imaging points IP1-IP3 by the imaging device 320 is the same, which will not be described in detail here. The beam splitter 422 and the focusing mirror 421 can generate multiple imaging points by focusing multiple image beams in the imaging point zone IPZ. The imaging point zone IPZ can be a target zone and can be set corresponding to the position of the user's eyeball.

[0027] It is worth mentioning that in this embodiment, the microlens groups ML11-ML33 can be arranged in an array of 3 times 3. In other embodiments of the present invention, the microlens groups can also be arranged in an array of N times N, where N can be any odd number greater than 3, such as 5 times 5, 7 times 7, etc.

[0028] Through the two-dimensionally arranged microlens groups ML11 - ML33 , the image display device 400 of this embodiment can generate a plurality of two-dimensional output sub-images in the imaging point zone IPZ, and can generate a complete output image by splicing these output sub-images.

[0029] In this embodiment, by splicing multiple output sub-images into a complete output image, the image field of the output image can be effectively expanded. Furthermore, under the premise that the image field of the output image is effectively expanded, when the user rotates the eyeball, there will be no image loss due to the imaging point not falling in the pupil.

[0030] In summary, the image display device of the present invention is provided with a plurality of microlens groups, and the microlens groups can generate a plurality of parallel image beams at different angles and without mutual interference, thereby expanding the distribution range of the image beams. In addition, the image beam is focused by an imaging device to generate a plurality of imaging points in the target area. The output image is generated by splicing a plurality of output sub-images corresponding to the plurality of imaging points. In this way, the distribution area of ​​the imaging points can be effectively expanded, and the field of view of the output image can be correspondingly expanded. For example, when the human eye is placed at the central viewpoint, the viewpoint viewed will be switched when the eyeball is rotated, and the image can be spliced ​​into an image with a larger field of view on the retina of the human eye. In addition, in an embodiment of the present invention, the microlens group can be provided without requiring an excessively large space, so that the effect of expanding the field of view of the output image can be achieved, and at the same time, a visible image can be maintained when the user's eyeball rotates.

[0031] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An image display device, comprising: A plurality of microlens groups are arranged in an array, the plurality of microlens groups receive display images and respectively generate a plurality of image light beams, and the traveling directions of the plurality of image light beams are not parallel to each other; and The imaging device receives the plurality of image beams, focuses the plurality of image beams to generate a plurality of focused image beams respectively, and projects the plurality of focused image beams to a target area so that each of the image beams forms an image in the target area. 2 . The image display device according to claim 1 , wherein each of the image light beams comprises a plurality of image sub-beams that are parallel to each other. 3 . The image display device according to claim 1 , wherein the plurality of image light beams generate a plurality of imaging points in the target area.

4. The image display device according to claim 1, wherein the imaging device comprises: A lens group receives the plurality of image beams and focuses the plurality of image beams to generate the plurality of image beams respectively; as well as The beam splitter has a reflective surface for receiving the plurality of image light beams and reflecting the plurality of image light beams to the target area. 5 . The image display device according to claim 4 , wherein the lens group comprises at least one convex lens.

6. The image display device according to claim 1, wherein the imaging device comprises: A beam splitter receives the plurality of image light beams and reflects the plurality of image light beams to generate a plurality of first light beams respectively; as well as a focusing mirror, receiving the plurality of first light beams, reflecting and focusing the plurality of first light beams to generate the plurality of focused image beams respectively, and projecting the plurality of focused image beams to the beam splitter, The multiple focused image light beams penetrate the beam splitter and are projected onto the target area.

7. The image display device according to claim 6, wherein the focusing mirror is a concave mirror. 8 . The image display device according to claim 1 , wherein the plurality of microlens groups are arranged in an N by N array, where N is an odd number greater than or equal to 3. 9 . The image display device according to claim 1 , wherein each of the microlens groups receives a plurality of sub-images of the display image respectively.

10. The image display device according to claim 1, wherein the plurality of image light beams are imaged into a plurality of output sub-images in the target area respectively, and the plurality of output sub-images are spliced ​​into an output image.

11. The image display device according to claim 1, further comprising: The image projector is used to emit the display image.

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