Stereoscopic image display device having multilayer functional film structure

Abstract

The present invention relates to a stereoscopic image display device in which a multilayer functional film structure applied to a head-up display device of a vehicle or the like is improved to improve manufacturing convenience and uniformity of 3D resolution. According to the present invention, a thick laminated base film in the multilayer functional film structure applied to the head-up display device is replaced with a glass plate, and thus the shrinkage and expansion rate of a lenticular lens is minimized, and manufacturing convenience and uniformity of 3D resolution can be improved to ensure reliability. In addition, deformation of a lens layer can be prevented even when the thickness of a lenticular lens formation layer is minimized, and the attachment structure of the lens to the glass plate can be simplified to ensure the uniformity of the lens, and thus marketability can be improved. In addition, by combining two lenses having different refractive indices in the lenticular lens, the height (SAG) of the lenticular lens can be made large while reducing the curvature to resolve difficulties in the manufacturing process, and thus productivity can be improved.

Description

Stereoscopic image display device having a multilayer functional film structure

[0001] The present invention relates to a stereoscopic image display device having a multilayer functional film structure, and more specifically, to a stereoscopic image display device that improves the multilayer functional film structure applied to a head-up display device (hereinafter referred to as a "HUD device") of a vehicle or the like, thereby improving manufacturing convenience and uniformity of 3D resolution.

[0002] The material described in this section merely provides background information on embodiments of the present invention and does not constitute prior art.

[0003] Head-up displays (HUDs) are increasingly being used to enhance driver safety and comfort. HUDs display instrument panel information such as vehicle speed, fuel level, and engine RPM, as well as navigation information. Beyond this information, augmented reality can be used to provide even more diverse information.

[0004] For example, lane movement direction, hazards, pedestrian locations, and building information ahead can be expressed in alignment with objects or the foreground.

[0005] However, existing head-up displays (HUDs) display virtual images at a fixed distance (typically 2.5 meters) and have a limited horizontal field of view of less than 5 degrees. Recently, HUDs with improved image distances of up to 10 meters and a horizontal field of view of up to 10 degrees have been developed or released as prototypes. Furthermore, there is a growing demand for a wider field of view, extending the range to 20 degrees or more.

[0006] To achieve this, large display panels are needed to address the issue of sunload caused by sunlight. However, as panel sizes increase, 3D HUDs utilizing lenticular lenses face the problem of significantly increasing the thickness of the base film. Furthermore, ensuring the uniformity of the lenticular lens over a large area becomes crucial.

[0007] Meanwhile, in order to carry out the thick base film manufacturing process, multiple soft molding processes (base film lamination structures) are required, and as a result, it is difficult to secure the uniformity of the lenticular lens, which has led to a problem in that the manufacturing process for securing 3D image quality has become difficult.

[0008] Therefore, in order to provide a HUD that employs a large display panel, it was urgent to develop a 3D optical multi-layer film structure having a new structure that can secure the uniformity of a lenticular lens while having a thin base film.

[0009] Prior art literature includes Korean Patent Publication No. 10-2022-0032448 (published on March 15, 2022, title: Method and device for compensating crosstalk).

[0010] The background technology described above is technical information that the inventor possessed for the purpose of deriving embodiments of the present invention or acquired during the derivation process, and cannot necessarily be said to be publicly known technology disclosed to the general public prior to the filing of the embodiments of the present invention.

[0011] In order to solve the problems of the prior art as described above, the purpose of the present invention is to provide a stereoscopic image display device having a multilayer functional film structure that can secure reliability by minimizing the shrinkage and expansion rate of a lenticular lens by replacing a thick laminated base film with glass.

[0012] In addition, an object of the present invention is to provide a stereoscopic image display device having a multilayer functional film structure capable of preventing deformation of the lens layer due to load by minimizing the thickness of the lenticular lens forming layer and ensuring uniformity of the lens by simplifying the structure.

[0013] And, the purpose of the present invention is to provide a stereoscopic image display device having a multilayer functional film structure that can reduce the curvature while forming a large height (SAG) of a lenticular lens by synthesizing two lenses having different refractive indices of the lenticular lens, thereby solving difficulties in the manufacturing process.

[0014] The technical problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0015] The present invention for solving such technical problems can be configured by including a backlight unit (10); a display panel (20) arranged on the front of the backlight unit (10); and a multi-layered 3D optical lens layer (30) arranged on the front of the display panel (20) and having a first glass plate (50) and a polymer-based lenticular lens array (40) on the front of a glass substrate (21) to provide a stereoscopic image.

[0016] In addition, the lenticular lens array (40) may be formed by including an attachment layer (41) provided on a first glass plate (50); a lens layer (43) in which lenticular lenses are continuously arranged on the front surface of the attachment layer (41); and a protective layer (45) provided on the front surface of the lens layer (43) and having a lower refractive index than the lens layer (43).

[0017] In addition, the lenticular lens array (40) may be formed by including an attachment layer (41) provided on a first glass plate (50); a lens layer (43) in which lenticular lenses are continuously arranged on the front surface of the attachment layer (41); a protective layer (45) having a lower refractive index than the lens layer (43) and provided on the front surface of the lens layer (43); and a second glass plate (55) attached to the front surface of the protective layer (45).

[0018] In addition, the above-mentioned adhesive layer (41) can be formed by attaching it to the front surface of the first glass plate (50) using any one of deposition, printing, and application in the form of dots or thin films.

[0019] In addition, the second glass plate (55) can be formed by attaching it to the front surface of the protective layer (45) using either deposition or printing in the form of a thin film.

[0020] In addition, the lenticular lens of the lens layer (43) may be configured to have a semicircular cross-section like “⌒” and be placed on the front of the attachment layer (41) to provide different images to the user’s left and right eyes, respectively, in order to provide a three-dimensional image.

[0021] According to the present invention, by replacing the multilayer functional film structure applied to a HUD device of a vehicle or the like with a glass plate in a thick laminated base film, the shrinkage and expansion rate of the lenticular lens is minimized, thereby improving manufacturing convenience and uniformity of 3D resolution, thereby ensuring reliability.

[0022] In addition, by minimizing the thickness of the lenticular lens forming layer, deformation of the lens layer can be prevented, and the uniformity of the lens can be secured by simplifying the structure for attaching the lens to the glass plate, thereby improving marketability.

[0023] In addition, by synthesizing two lenses with different refractive indices of the lenticular lens, the height (SAG) of the lenticular lens can be formed to be large while reducing the curvature, thereby solving the difficulty of the manufacturing process, thereby improving productivity.

[0024] In addition, the effects of the present invention have various effects, such as excellent versatility depending on the embodiment, and such effects can be clearly confirmed in the description of the embodiments described below.

[0025] FIG. 1 is a schematic cross-sectional view of a stereoscopic image display device having a multilayer functional film structure according to the present invention.

[0026] FIG. 2 is a schematic cross-sectional view of a stereoscopic image display device having a multilayer functional film structure according to an embodiment of the present invention.

[0027] Figure 3 is a schematic diagram showing the refractive index of a stereoscopic image display device having a multilayer functional film structure according to the present invention.

[0028] Figure 4 is a graph comparing the lens shrinkage ratio of a stereoscopic image display device having a multilayer functional film structure according to the present invention.

[0029] Figure 5 is a graph comparing the LCD surface temperatures of a stereoscopic image display device having a multilayer functional film structure according to the present invention.

[0030] The advantages and features of the present invention, and the methods for achieving them, will become clearer with reference to the embodiments described in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments presented below, but can be implemented in various different forms, and it should be understood that it includes all transformations, equivalents, and substitutes included in the spirit and technical scope of the present invention. The embodiments presented below are provided to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the invention of the scope of the invention. In describing the present invention, if a detailed description of related known technologies is judged to obscure the gist of the present invention, the detailed description thereof will be omitted.

[0031] The terminology used in this application is solely for the purpose of describing specific embodiments and is not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise.

[0032] In this application, terms such as "comprises" or "has" are intended to indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but should be understood as not excluding in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. Terms such as first, second, etc. may be used to describe various components, but the components should not be limited by these terms. These terms are used solely for the purpose of distinguishing one component from another.

[0033] Hereinafter, embodiments according to the present invention will be described in detail with reference to the attached drawings. In describing with reference to the attached drawings, identical or corresponding components are given the same drawing reference numerals and redundant descriptions thereof are omitted.

[0034] First, the backlight unit (10) is configured to emit a wide-angle light source on a surface, and to change and transmit a two-dimensional image generated by a picture generation unit (hereinafter referred to as 'PGU) composed of a display panel (20) arranged in front of the backlight unit (10) into a virtual image on the windshield of the automobile. The configuration of the backlight unit (10) and the display panel (20) can be applied in various ways according to the needs of those skilled in the art, and is not limited to a specific one.

[0035] In addition, it is preferable that the backlight unit (10) be configured as a high-brightness backlight having a divergence angle of less than 10 degrees so that the image can be clearly seen even under strong sunlight.

[0036] The present invention arranges a 3D optical lens layer (30) on the front of the display panel (20), thereby minimizing the shrinkage or expansion rate of a lenticular lens array (40) due to heat generated by a backlight unit (10) and sunlight, thereby improving the uniformity of the HUD 3D resolution provided to a vehicle, etc.

[0037] To this end, a multi-layered 3D optical lens layer (30) having a first glass plate (50) and a polymer-based lenticular lens array (40) for providing a three-dimensional image is installed on the front surface of the glass substrate (21) of the display panel (20), and arranged to block heat transfer to the lenticular lens array (40) through the display panel, thereby minimizing shrinkage or expansion rate of the lenticular lens array (40) due to the backlight unit (10) and sunlight.

[0038] The above lenticular lens array (40) is formed by including an adhesive layer (41) for fixing to one surface of a first glass plate (50) that is in contact with a glass substrate (21) of a display panel (20), as shown in FIG. 1, a lens layer (43) in which lenticular lenses are continuously arranged on the front surface of the adhesive layer (41), and a protective layer (45) having a lower refractive index than the lens layer (43) and provided on the front surface of the lens layer (43).

[0039] At this time, it is preferable to simplify the structure of the lens layer (43) on which the lenticular lens is arranged so as to minimize the thickness based on the first glass plate (50) while preventing deformation of the lens layer due to the load of the protective layer and the second glass plate, etc., which will be described later, so as to ensure uniformity in the arrangement of the lenticular lens.

[0040] In addition, the lenticular lens array (40) is also included in the present invention in that it is formed by including an attachment layer (41) provided on a first glass plate (50) as in FIG. 2, a lens layer (43) in which lenticular lenses are continuously arranged on the front surface of the attachment layer (41), a protective layer (45) having a lower refractive index than the lens layer (43) and provided on the front surface of the lens layer (43), and a second glass plate (55) attached to the front surface of the protective layer (45).

[0041] Therefore, the uniformity of the 3D resolution of the HUD can be improved by minimizing the shrinkage or expansion rate of the lenticular lens array (40) due to heat from sunlight.

[0042] Here, the above-mentioned adhesive layer (41) can be attached to the front surface of the first glass plate (50) by using any one of deposition, printing, and application in the form of dots or thin films.

[0043] The above-mentioned adhesive layer (41) is irradiated with ultraviolet rays by operating an ultraviolet lamp at a certain distance from the surface of the first glass plate (50) using a transparent UV curing agent, so that the ultraviolet rays pass through the transparent first glass plate and cure the UV curing agent, thereby allowing the lens layer (43) to be attached to the first glass plate (50).

[0044] In addition, the lenticular lenses regularly arranged on the lens layer (43) have a cross-section in the shape of a semicircle like “⌒” and are arranged in a pattern that is continuously repeated on the front surface of the adhesive layer (41) to provide different images to the left and right eyes of the user, respectively, in order to provide a three-dimensional image.

[0045] The above lenticular lens has the effect of having a horizontal cross-section of the major diameter arranged on the adhesive layer (41) and is arranged in a continuous and repeated manner as a whole, and it is preferable to configure the lenticular lens so that the major diameter is at least 2 to 3 times longer than the minor diameter of the arc shape and the curvature is small, while the minor diameter of the lenticular lens is formed so that the minor diameter of the lenticular lens is increased overall, thereby improving the manufacturing efficiency.

[0046] In addition, a transparent protective layer (45) is attached to the front surface of the lenticular lens in the form of a thin film using one of deposition, printing, and coating. When a UV lamp is operated at a certain distance from the surface of the first glass plate (50) using a UV curing agent and ultraviolet rays are irradiated, the ultraviolet rays pass through the transparent first glass plate and harden the UV curing agent, thereby fixing the protective layer (45) to the front surface of the lenticular lens.

[0047] The above protective layer (45) improves the surface strength of the lens layer (43) and prevents the moire phenomenon, in which an image transmitted through a lenticular lens is distorted into a wave pattern, thereby improving the uniformity of the 3D image.

[0048] That is, since the change in curvature of the valley portion of a lenticular lens having a semicircular arc shape is relatively greater than the change in curvature of the apex portion, a difference in the amount of light transmitted between the apex and valley portion of the lenticular lens occurs, generating moire in a 3D image. However, a protective layer (45) having a lower refractive index than the refractive index of the valley portion of the lenticular lens is formed on the entire surface of the lens layer (43), thereby improving the uniformity of 3D resolution.

[0049] The above protective layer (45) is composed of a composition having a lower refractive index than that of the lenticular lens, and is formed by filling the groove portion of the lenticular lens, thereby lowering the curvature even when the height of the lenticular lens is increased, thereby improving the uniformity of 3D resolution along with manufacturing convenience.

[0050] And, as shown in Fig. 3, the protective layer (45) filled in the valley portion of the lenticular lens does not cause changes in the height (SAG) and curvature of the lenticular lens, so it is okay to form the protective layer (45) so that it protrudes more than the apex of the lenticular lens.

[0051] The above protective layer (45) is a composition in which transparent silicone (LSR; Liquid Silicone Rubber) having a light transmittance of 94% or more, a UV curing agent, and polyurethane acrylate are mixed in a ratio of approximately 3:6:1. It is preferable that the particles of polyurethane acrylate have a size of 5 ㎛ to 20 ㎛ and are mixed. The present invention also includes a composition in which the UV curing agent and polyurethane acrylate are mixed in a ratio of approximately 8:2.

[0052] And, a transparent second glass plate (55) is formed by being attached to the front surface of the protective layer (45), and the second glass plate (55) has a thickness of at least 0.1 to 2T and is configured by having an adhesive layer provided on one surface in the form of a thin film using either deposition or printing so as to be attached to the front surface of the protective layer (45).

[0053] Accordingly, the lenticular lens array (40) arranged on the front surface of the first glass plate (50) can minimize the shrinkage or expansion rate of the lenticular lens array (40) due to heat from sunlight by the second glass plate (55).

[0054] Fig. 4 is a graph comparing the shrinkage rate of a lenticular lens equipped on a glass plate and an existing polymer synthetic resin film due to heat generated by a backlight unit (10) and sunlight, and shows that the shrinkage rate of a 3D optical lens layer (30) configured as in the present invention is low.

[0055] FIG. 5 is a graph showing the time it takes for the temperature of the existing polymer synthetic resin film and the first glass plate (50) to reach the surface temperature of the glass substrate (21) of the display panel (20). It can be seen that the temperature of the first glass plate (50) configured as in the present invention reaches the temperature later than the polymer synthetic resin film, thereby improving reliability.

[0056] Therefore, the idea of ​​the present invention should not be limited to the embodiments described above, and not only the scope of the patent claims described below but also all scopes equivalent to or equivalently modified from the scope of the patent claims are considered to fall within the scope of the idea of ​​the present invention.

[0057] ** Explanation of symbols **

[0058] 10: Backlight 20: Display panel

[0059] 21: Glass substrate 30: 3D optical lens layer

[0060] 40: Lenticular lens array 41: Adhesive layer

[0061] 43: Lens layer 45: Protective layer

[0062] 50: First glass plate 55: Second glass plate

Claims

1. Backlight unit (10); A display panel (20) placed on the front of the above backlight unit (10); and A stereoscopic image display device having a multilayer functional film structure, characterized by having a multilayer structured 3D optical lens layer (30) provided with a first glass plate (50) and a polymer-based lenticular lens array (40) on the front of a glass substrate (21) to provide a stereoscopic image, and arranged on the front of the display panel (20).

2. In paragraph 1, The above lenticular lens array (40) is An adhesive layer (41) provided on the first glass plate (50); A lens layer (43) in which lenticular lenses are continuously arranged on the front surface of the above-mentioned adhesive layer (41); and A stereoscopic image display device having a multilayer functional film structure characterized by including a protective layer (45) provided on the front surface of the lens layer (43) and having a refractive index lower than that of the lens layer (43).

3. In paragraph 1, The above lenticular lens array (40) is An adhesive layer (41) provided on the first glass plate (50); A lens layer (43) in which lenticular lenses are continuously arranged on the front surface of the above-mentioned adhesive layer (41); A protective layer (45) having a lower refractive index than that of the lens layer (43) and provided on the front surface of the lens layer (43); and A stereoscopic image display device having a multilayer functional film structure characterized by including a second glass plate (55) attached to the front surface of the above protective layer (45).

4. In paragraph 2 or 3, The above adhesive layer (41) is A stereoscopic image display device having a multilayer functional film structure characterized by being formed by attaching in the form of dots or thin films on the front surface of a first glass plate (50) using any one of deposition, printing, and application.

5. In paragraph 3, The above second glass plate (55) is A stereoscopic image display device having a multilayer functional film structure characterized by being formed by attaching a thin film on the entire surface of a protective layer (45) using either deposition or printing.

6. In paragraph 2 or 3, The lenticular lens of the above lens layer (43) is A stereoscopic image display device having a multilayer functional film structure characterized in that it has a semicircular arc-shaped cross-section like “⌒” and is placed on the front of an adhesive layer (41) to provide different images to the left and right eyes of the user, respectively, in order to provide a three-dimensional image.

Images