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EP-4741908-A1 - ELECTRONIC DEVICE

EP4741908A1EP 4741908 A1EP4741908 A1EP 4741908A1EP-4741908-A1

Abstract

The present disclosure relates to an electronic device, such as a wearable display, which is provided with a pinhole array configured to further improve the quality of an image visible to a user. The present disclosure may provide an electronic device comprising: a transparent substrate; a light source module array which is provided at a first surface of the transparent substrate and has a plurality of light source modules arranged in a lattice structure; a pinhole array which is provided at a second surface of the transparent substrate and has a plurality of micro-cluster pinholes arranged to correspond to the plurality of light source modules respectively; and an optical driving unit which controls the light source module array, wherein light beams according to an image generated by the optical driving unit are emitted from the light source module array and provided to a user through the pinhole array.

Inventors

  • JU, Yeongyeong
  • Shin, Sungchul
  • JEONG, Moongi

Assignees

  • LG Electronics Inc.

Dates

Publication Date
20260513
Application Date
20230802

Claims (18)

  1. An electronic device comprising: a transparent substrate; a light source module array disposed on a first surface of the transparent substrate and having a plurality of light source modules arranged in a lattice structure; a pinhole array disposed on a second surface of the transparent substrate and having a plurality of micro cluster pinholes defined therein and arranged to correspond to the plurality of light source modules, respectively; and an optical driver configured to control the light source module array, wherein light beams based on an image generated by the optical driver are irradiated from the light source module array and provided to a user through the pinhole array.
  2. The electronic device of claim 1, wherein each micro cluster pinhole comprises a plurality of micro pinholes.
  3. The electronic device of claim 2, wherein each micro pinhole has a hexagonal opening, and the plurality of micro pinholes are arranged such that a separation distance between micro pinholes adjacent to each other is uniform.
  4. The electronic device of claim 2, wherein a ratio between an aperture of each micro pinhole to the separation distance between the micro pinholes adjacent to each other is in a range of 1:1 to 1:20.
  5. The electronic device of claim 4, wherein the aperture of the micro pinhole is in a range of 5µm to 100µm, and the separation distance between the micro pinholes adjacent to each other is in a range of 5µm to 2000µm.
  6. The electronic device of claim 5, wherein a separation distance between micro cluster pinholes adjacent to each other is in a range of 1:1.8 to 1:2.2.
  7. The electronic device of claim 6, wherein an aperture of each micro cluster pinhole is in a range of 100µm to 1500µm, and the separation distance between the micro cluster pinholes adjacent to each other is in a range of 200µm to 3000µm.
  8. The electronic device of claim 7, wherein the separation distance between the micro pinholes adjacent to each other increases from a center of each micro cluster pinhole toward a periphery thereof.
  9. The electronic device of claim 1, wherein each micro cluster pinhole is defined in a manner such that at least two layers are stacked.
  10. The electronic device of claim 9, wherein a plurality of micro pinholes are defined in each layer; and the at least two layers stacked such that the micro pinholes in the respective layers at least partially overlap each other or are at least partially covered by each other.
  11. The electronic device of claim 10, wherein at least one of a shape, a size, and a separation spacing of the micro pinholes in one layer is different from at least one of a shape, a size, and a separation spacing of the micro pinholes in another layer.
  12. The electronic device of claim 1, wherein each light source module is composed of a cluster of light source elements.
  13. The electronic device of claim 12, wherein each light source element comprises a liquid crystal on silicon (LCoS) element, a liquid crystal display (LCD) element, an organic light emitting diode (OLED) element, a digital micromirror device (DMD) element, a micro light emitting diode (LED) element, and a quantum dot (QD) LED element.
  14. The electronic device of claim 1, wherein the electronic device is a wearable display, wherein the transparent substrate is disposed such that the first surface thereof faces an outside and the second surface thereof faces a user when the wearable display is worn.
  15. The electronic device of claim 14, wherein the wearable display comprises a front frame and a side frame, wherein the transparent substrate is disposed on the front frame, and the optical driver is disposed on the side frame.
  16. The electronic device of claim 15, wherein the transparent substrate is flat or has a predetermined curvature.
  17. The electronic device of claim 1, further comprising an image division circuit configured to divide the image generated by the optical driver and transmit the divided images to the respective light source modules.
  18. The electronic device of claim 1, wherein a scale of the lattice structure is determined based on at least one of a distance between the light source module array and a user's pupil, a pupil size, an optical wavelength band.

Description

[Technical Field] The present disclosure relates to an electronic device, and more particularly, to an electronic device such as a wearable display used in Virtual Reality (VR), Augmented Reality (AR), Mixed Reality (MR), and the like. [Background] Virtual reality (VR) refers to a specific environment, situation, or technology itself that is similar to reality created by artificial technology using computers or the like, but is not real. Augmented Reality (AR) refers to a technology that synthesizes virtual objects or information in a real environment and makes them look like objects existing in an original environment. Mixed reality (MR) or hybrid reality refers to creating a new environment or new information by combining a virtual world and a real world. In particular, it is called mixed reality when it refers to something that can interact in real time between real and virtual things. In this case, the created virtual environment, situation, or the like stimulates user's five senses and allows them to freely enter and exit the boundary between reality and imagination by allowing them to experience space and time similar to the real thing. In addition, users may not only simply immerse themselves in this environment, but also interact with things implemented in this environment, such as manipulating or issuing commands using a real device. Recently, research on equipment (gear) used in such technical fields is being actively conducted. Wearable displays producing an image in the air are generally divided into two types. That is, there are a helmet-type wearable display worn on a user's head and a glasses-type wearable display. A helmet-type wearable display has a structure in which an optical lens system has an increased volume so as to produce a large image through an expanded field of view (FOV) and is mounted on a user's head, and is thus referred to as a head mounted display (HMD). Therefore, the helmet-type wearable display is used in professional fields requiring a restricted space with little motion, such as military training (cyber flight training) and cyber games. On the other hand, a glasses-type wearable display, as exemplarily shown in FIG. 1, has a lightweight and small-sized structure that is mounted on user's nose and ears like the structure of glasses and is easily used while in motion. Glasses-type wearable displays are divided into three structures. First, a direct view structure (FIG. 1 (1-1)), in which panel and a lens are fixed in front of the eyes, is most classic and basic in design of a virtual image optical system and is formed in a see-closed type in which a user may see an external view. Therefore, the direct view structure (FIG. 1 (1-1)) needs to recognize an external view in a moving space and is thus disadvantageous. Second, in order to solve the disadvantage of the direct view structure (FIG. 1 (1-1)), a top-fixed reflection structure (FIG. 1 (1-2)), in which a panel is fixed at the top and a user may see an external view using a partially reflective surface, is provided. However, since the panel and an optical system group are generally fixed in front of the eyes, the top-fixed reflection structure (FIG. 1 (1-2)) is difficult to have a thin thickness as in a general glasses structure and a light weight. Third, a side-fixed light guide structure (FIG. 1 (1-3)), in which a panel and an optical lens group are moved from the front to side frames at the side of eyes and is similar to a glasses lens using a light guide, is provided. Side-fixed light guide structures (FIG. 1 (1-3)) are divided into a PBS type (FIG. 2 (2-1)) and a prism type (FIG. 2 (2-2)) so as to transmit beams to a pupil through internal reflection of a planar light guide, as exemplarily shown in FIG. 2. Since special partial coating of several tens of layers is performed on respective PBS plane segments and then the segments are bonded so as to uniformly emit beams from respective mirrors and the top-fixed reflection structure (FIG. 2 (2-1)) is formed of a restricted material, such as glass, the top-fixed reflection structure (FIG. 2 (2-2)) is difficult to mass produce using a mold structure. On the other hand, the prism type structure 220 may be manufactured using a mold structure and be easily formed of plastic. However, a lens group is disposed distant from the eyes through total internal reflection and thus the two planar light guide types are limited in extension of an FOV and a PBS or prism pattern is virtually visible. Further, beams are reflected within the effective range of partial PBS mirrors or a prism mirror changing a path to guide the beams to pupils through total internal reflection of a planar light guide and, thus, the conventional methods are limited in the FOV determining the size of an image. As exemplarily shown in FIG. 3, in order to form a range in which beams do not overlap to perform internal reflection, an effective segment partial PBS mirror range (FIG. 3 (3-1)) or a prism mirror ra