KR102667889B1 - Image display device using partial reflector array and wedge reflective prism - Google Patents

Abstract

The object of the present invention is to provide an image display device using a split reflection array and a wedge prism capable of minimizing the size and thickness of an incident portion. An image display device includes: a display element (30) that generates image light (37); a polarizing plate (301) that faces the display element (30) in parallel and determines a polarization component of S-pol or P-pol; and a waveguide (31) that is provided on one side of the polarizing plate (301), and through which the image light (37) transmitted through the polarizing plate (301) is incident, expands an emission aperture of the incident image light (37) in a first direction, and emits the image light toward a user (15). According to the present invention, the volume of an incident optical system, which has been a limitation in reducing the volume of an image display device having a waveguide structure, can be drastically reduced.

Description

Image display device using partial reflector array and wedge reflective prism}

The present invention relates to a transmissive image display device, and more specifically, to a segmentation device that can project image light and external image light to the user's eyes with high efficiency while minimizing size and thickness and eliminating asymmetric distortion of the image. This relates to an image display device using a reflective array and wedge prism.

In general, a head mounted display (HMD) is a device that displays images while worn on the user's head. Recently, technology for providing virtual reality or augmented reality content using head-mounted displays is increasing.

A transmissive HMD optical system using a diffractive waveguide is applied to this head-mounted display. Figure 6 is a conceptual diagram of a conventional eye box expansion diffraction optical system. As shown in FIG. 6, the diffractive light guide plate 10 is provided on one side or the other side of the light guide portion 11 and the light guide portion 11 and includes a plurality of diffractive optical elements ( 12, 13, 14) can be provided. The diffraction light guide plate 10 includes an input diffraction optical element 12 that allows the light output through the light source output module 5 to be input and guided onto the light guide unit 11, and an input diffraction optical element 12 that allows the light output through the light source output module 5 to be input and guided onto the light guide unit 11. An intermediate device that is optically coupled to the optical element 12 and allows one-dimensional expansion of the light received from the input diffractive optical element 12 in the first direction (x-axis direction in FIG. 1) by diffraction. It is optically coupled to the intermediate diffractive optical element 13 through the diffractive optical element 13 and the light guide unit 11, and directs the light received from the intermediate diffractive optical element 13 in a second direction (in FIG. 1) by diffraction. It is provided with an output diffraction optical element 14 that allows output from the light guide unit 11 to be directed to the pupil of the user 15 with one-dimensional expansion in the y-axis direction).

In this conventional diffractive optical system, the main optical path for the light output through the light source output module 5 to reach the pupil of the user 15 is: input diffractive optical element 12 - intermediate diffractive optical element 13 - output The diffractive optical element 14 is followed by the pupil of the user 15. Compared to the area of the first input diffractive optical element 12, the area of the output light output from the final output diffractive optical element 14 is much larger both horizontally (x-axis direction) and vertically (y-axis direction), so the horizontal and vertical exit pupil ( eye-box) has been expanded so that users can view the output video light more comfortably. Here, the exit pupil refers to the largest area size where the same image light can be seen at the maximum viewing angle. The larger the exit pupil, the larger the range in which the user's 15 pupil can be positioned, allowing the user to increase convenience of use.

However, in such a conventional exit pupil expansion diffractive optical system, the input diffractive optical element 12, the intermediate diffractive optical element 13, and the output diffractive optical element 14 are arranged separately from each other on the light guide unit 11, and the image light Since a lot of total internal reflection and diffraction occur from input to output, the surface of the light guide 11 and each diffractive optical element 12, 13, and 14 had to be processed very precisely. Otherwise, there is a high possibility of double images occurring in the image or outputting unclear images, which has the disadvantage of greatly reducing mass production.

In addition, due to the physical characteristics of diffraction, not only was the amount of diffracted light at the desired angle much smaller than the amount of reflected light through geometric optics, but the image light was output through a total of three diffraction reactions, so light efficiency was very low. Because of this, it has the additional disadvantage of having to use very strong incident light. In addition, since diffraction occurs in multiple directions, output light is generated not only in the direction of the user's pupil but also in the opposite direction, so the screen that the user is viewing can be viewed from the outside at the same time, which could cause a security problem.

1. U.S. Patent Publication No. 20160231568, 2. Republic of Korea Patent Registration No. 10-2201723, 3. Republic of Korea Patent Registration No. 10-977232.

Therefore, the present invention was made to solve the above problems, and the first object of the present invention is to provide an image display device using a split reflection array and wedge prism that can minimize the size and thickness of the incident part. .

A second object of the present invention is to provide an image display device using a split reflection array and a wedge prism that can eliminate asymmetric distortion of images.

The third object of the present invention is to provide an image display device using a segmented reflection array with an exit pupil expansion function and a wedge prism so that users with various eye spacings or eye positions can obtain image information without loss.

In addition, the fourth object of the present invention is to simplify the structure of the image light extraction means in the waveguide by incorporating a sawtooth partial reflection array structure to enable plastic injection mass production, and to achieve reflection by applying a uniform functional coating to the entire sawtooth structure. By manufacturing arrays, the unit price of the product is lowered and a cost-competitive split reflection array and image display device using a wedge prism are provided.

The fifth object of the present invention is to not only increase the extraction efficiency of image light heading toward the user's pupil by applying a polarizing coating with angular bias on the polarizer and sawtooth structure, but also block the optical path output in the direction opposite to the pupil, thereby blocking the light path from the outside. It provides an optical system with enhanced security by preventing users from viewing the same video they are watching.

However, the technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly apparent to those skilled in the art from the description below. It will be understandable.

In order to achieve the above technical problem, as a first embodiment of the present invention, an optical system for augmented reality glasses includes a display element 30 that generates image light 37; A polarizer 301 faces the display element 30 in parallel and determines the polarization component of S-pol or P-pol; and is provided on one side of the polarizer 301, the image light 37 passing through the polarizer 301 is incident, and the exit pupil of the incident image light 37 is expanded in the first direction to be emitted toward the user 15. It includes a waveguide 31, wherein the image light 37 is incident and totally reflected, and includes a first surface 312 and a second surface 313 that are parallel to each other; An incident surface 311 forming a predetermined incident angle θi with the first surface 312 at one end of the waveguide 31; An end surface 314 forming an end inclination angle θ _L with the first surface 312 at the other end of the waveguide 31; A phase shift film 321 attached to one side of the end surface 314; A curved mirror (32) attached to one side of the phase shift film (321); A wedge prism 315 installed inclined at a predetermined wedge angle (θ ₂ ) with the first surface 312; Polarization reflective coating 316 attached to one side of the wedge prism 315; It is provided on the second surface 313, and the transmission surface 324a through which the image light 37 reflected from the wedge prism 315 transmits and the reflection surface 324b through which the transmitted image light 37 reflects are mutually Split reflection arrays 317 are provided alternately to form a sawtooth structure; and a polarizing coating layer 325 formed on the sawtooth structure and having angular deflection to exhibit different reflectance depending on the angle of incidence on the transmission surface 324a or the reflection surface 324b. An image display device using a wedge prism is provided.

In order to achieve the object of the present invention as described above, as a second embodiment, an optical system for augmented reality glasses includes a display element 30 that generates image light 37; A polarizer 301 faces the display element 30 in parallel and determines the polarization component of S-pol or P-pol; and is provided on one side of the polarizing plate 301, the image light 37 passing through the polarizing plate 301 is incident, and the exit pupil of the incident image light 37 is expanded in the first direction to be emitted toward the user 15. It includes a waveguide 31, wherein the image light 37 is incident and totally reflected, and includes a first surface 312 and a second surface 313 that are parallel to each other; An incident surface 311 forming a predetermined incident angle θ _i with the first surface 312 at one end of the waveguide 31; An end surface 314 forming an end inclination angle θ _L with the first surface 312 at the other end of the waveguide 31; A phase shift film 321 attached to one side of the end surface 314; A flat convex lens (35) attached to one side of the phase shift film (321); A wedge prism 315 installed inclined at a predetermined wedge angle (θ ₂ ) with the first surface 312; Polarization reflective coating 316 attached to one side of the wedge prism 315; It is provided on the second surface 313, and the transmission surface 324a through which the image light 37 reflected from the wedge prism 315 transmits and the reflection surface 324b through which the transmitted image light 37 reflects are mutually Split reflection arrays 317 are provided alternately to form a sawtooth structure; and a polarizing coating layer 325 formed on the sawtooth structure and having angular deflection to exhibit different reflectance depending on the angle of incidence on the transmission surface 324a or the reflection surface 324b. An image display device using a wedge prism is provided.

Additionally, the end surface 314 and the curved mirror 32 have a curvature that allows the totally reflected image light 37 to form a first focus F1 within the waveguide 31.

Additionally, the end surface 314 is flat, and the plano-convex lens 35 has a mirror surface so that the image light 37 is reflected.

Additionally, the curved mirror 32 has a mirror surface so that the image light 37 is reflected.

Additionally, the phase shift film 321 is a λ/4 phase shift film 321.

Additionally, the polarization reflection coating 316 and the polarization coating layer 325 reflect the same polarization component.

Additionally, the angle of incidence (θ _i ) and the angle of inclination (θ _L ) are the same.

In addition, in order for the image light 37 to be totally reflected in the first surface 312, the minimum angle of incidence (θ ₀ ) of the image light 37 satisfies the following equation,

Here, n is the refractive index of the waveguide 31, and θ _c is the critical angle for total reflection.

In addition, in order for the center light of the image light 37 to be emitted vertically toward the eyes of the user 15, the following equation is satisfied,

Here, θ ₁ is the reflection angle of the split reflection array 317, and θ ₂ is the wedge angle of the wedge prism 315.

In addition, the polarizing coating layer 325 is a partially reflective coating layer that can reflect the image light 37 and transmit the external image 50 at the same time.

Additionally, the image display device of the present invention may have a coaxial optical structure so that the central light of the image light 37 can be emitted vertically toward the eyes of the user 15.

According to one embodiment of the present invention, the volume of the optical system at the entrance, which is a limitation in reducing the volume of the image display device with a waveguide structure, can be dramatically reduced.

In addition, it has a curved mirror, which is the most advantageous structure for magnifying image light, as the main image magnification means, and by installing it in a position close to the exit pupil (F1) in the waveguide, it minimizes the thickness and volume of the optical system while providing a wide viewing angle. You can get it.

In addition, the center light of the image light emitted from the display 30 is incident vertically through the waveguide incident surface 311, is emitted vertically through the end surface 314, and is reflected by the curved mirror 32 to return to the waveguide ( 31) is incident vertically into the inside, and is reflected from one side of the wedge prism 315. Then, it is reflected from the reflective surface 324b of the split reflection array and is emitted vertically through the second plane 313 of the waveguide to be incident vertically toward the user's eyes. Therefore, it is possible to minimize distortion of image light while eliminating image distortion caused by off-axis. Therefore, it is advantageous to implement a shape like glasses by arranging the display not only top-down but also horizontally.

Additionally, by installing a split reflection array along with a curved mirror in the waveguide, the focused image light can be diffused again and then divided and reflected by the split reflection array to be emitted. Because of this, a more expanded eye box can be provided. Therefore, users with various eye spacing or eye positions can easily obtain screen information.

In addition, a polarizing plate or polarizing coating is used in the waveguide to guide the polarized beam, and in the split reflection array, image light is transmitted at small angles of incidence, and a polarizing coating with high reflectivity is applied at angles with a large incident angle of 30 degrees or more to produce image light. Light efficiency and transmission efficiency can be improved when securing external visibility.

In addition, the split reflection array is formed in a sawtooth structure, so it is manufactured as a single piece through injection molding, and can be manufactured by applying a uniform polarizing coating to the entire sawtooth structure. As a result, the manufacturing process and coating process can be simplified to lower the unit cost of the product.

In addition, an augmented reality system that can simultaneously view the external image 50 and the image light 37 from the display element 30 can be implemented.

However, the effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned above will be clearly understood by those skilled in the art from the description below. You will be able to.

The following drawings attached to this specification illustrate preferred embodiments of the present invention, and serve to further understand the technical idea of the present invention together with the detailed description of the invention described later. Therefore, the present invention includes the matters described in such drawings. It should not be interpreted as limited to only .
1 is a configuration diagram of an image display device using a split reflection array and a wedge prism according to a first embodiment of the present invention;
Figure 2 is a configuration diagram of an image display device using a split reflection array and a wedge prism according to a second embodiment of the present invention;
Figure 3 is an enlarged view of the entrance surface 311 of the present invention.
Figure 4 is a graph showing the optical characteristics of the functional polarizing coating layer 325 according to the present invention.
Figure 5 is a partial enlarged view of the split reflection array 317 shown in Figures 1 and 2;
Figure 6 is a conceptual diagram of a conventional exit pupil expansion diffraction optical system.

Below, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, since the description of the present invention is only an example for structural or functional explanation, the scope of the present invention should not be construed as limited by the examples described in the text. In other words, since the embodiment can be modified in various ways and can have various forms, the scope of rights of the present invention should be understood to include equivalents that can realize the technical idea. In addition, the purpose or effect presented in the present invention does not mean that a specific embodiment must include all or only such effects, so the scope of the present invention should not be understood as limited thereby.

The meaning of terms described in the present invention should be understood as follows.

Terms such as “first” and “second” are used to distinguish one component from another component, and the scope of rights should not be limited by these terms. For example, a first component may be named a second component, and similarly, the second component may also be named a first component. When a component is referred to as being “connected” to another component, it should be understood that it may be directly connected to the other component, but that other components may also exist in between. On the other hand, when a component is said to be “directly connected” to another component, it should be understood that there are no other components in between. Meanwhile, other expressions that describe the relationship between components, such as “between” and “immediately between” or “neighboring to” and “directly neighboring to”, should be interpreted similarly.

Singular expressions should be understood to include plural expressions, unless the context clearly indicates otherwise, and terms such as “comprise” or “have” refer to the specified features, numbers, steps, operations, components, parts, or them. It is intended to specify the existence of a combination, and 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.

All terms used herein, unless otherwise defined, have the same meaning as commonly understood by a person of ordinary skill in the field to which the present invention pertains. Terms defined in commonly used dictionaries should be interpreted as consistent with the meaning they have in the context of the related technology, and cannot be interpreted as having an ideal or excessively formal meaning unless clearly defined in the present invention.

Configuration of the first embodiment

Hereinafter, the configuration of the preferred embodiment will be described in detail with reference to the attached drawings. FIG. 1 is a configuration diagram of an image display device using a split reflection array and a wedge prism according to a first embodiment of the present invention, FIG. 3 is an enlarged view of a portion of the incident surface 311 of the present invention, and FIG. 5 is a diagram of FIG. 1 This is a partial enlarged view of the split reflection array 317 shown in . As shown in FIGS. 1, 3, and 5, the present invention roughly consists of a display panel unit 30 and a waveguide 31.

The display panel unit 30 is a microdisplay with a fine pixel structure such as an LCD panel, OLED panel, OLEDos panel, or LCOS panel, and outputs image light 37.

The polarizer 301 is provided in parallel with the display panel unit 30 and selectively passes the polarization component of S-pol or P-pol. In this embodiment, the polarizer 301 selects the polarization component of P-pol. The polarizer 301 is a reflective polarizing film, an absorptive polarizing film, a polarizing coating that can convert an unpolarized beam or a partially polarized beam into a linearly polarized beam and transmit or reflect it, and a phase shift element to change the direction of the polarization component. It can be at least one of the means of conversion.

The waveguide 31 receives image light 37 from the polarizer 301 and expands the exit pupil of the incident image light 37 in the horizontal direction to emit it toward the user 15. The waveguide 31 has first and second surfaces 312 and 313 that are parallel to each other, and an incident surface 311 enlarged in a tapered shape is integrally formed at one end. The incident surface 311 forms a predetermined incident angle θi (eg, 50° to 80°) from the first surface 312 and is located parallel to the display panel unit 30.

As shown in FIG. 3, in order for the image light 37 to be totally reflected at the first surface 312, the minimum angle of incidence (θ ₀ ) of the image light 37 satisfies the following equation,

Here, n is the refractive index of the waveguide 31, and θ _c is the critical angle for total reflection.

Through this, the minimum incident angle (θ ₀ ) of the image light 37 with respect to the waveguide incident surface 311 has an angle range within which total reflection can occur on the first surface 312 .

As shown in FIG. 1, a waveguide end surface 314 forming an end inclination angle θ _L from the first surface 312 is formed at the other end of the waveguide 31. In one embodiment, the end surface inclination angle (θ _L ) may range from 50° to 80°, and the incident angle (θ _i ) of the incident surface 311 and the end surface inclination angle (θ _L ) are the same. A λ/4 phase shift film 321 is attached to the outer surface of the end surface 314, and a curved mirror 32 is attached to the outer surface of the λ/4 phase shift film 321. And, the curved mirror 32 has a mirror surface so that the image light 37 is reflected. Additionally, the end surface 314 and the curved mirror 32 have a curvature that allows the totally reflected image light 37 to form a first focus F1 within the waveguide 31.

That is, the curved mirror 32 is integrated and disposed on the end surface 314 of the waveguide 31, so that a means for magnifying the image light 37 can be placed close to the user's pupil, thereby forming a wide viewing angle. It is possible to provide an advantageous structure and at the same time minimize the size and volume of the incident area.

One end of the wedge prism 315 is installed inclined at a predetermined wedge angle θ ₂ (eg, 1° to 20°) at a point where the first surface 312 and the end surface 314 meet. A polarizing reflection coating 316 is attached to one side of the wedge prism 315 facing the split reflection array 317. One side of the wedge prism 315 has an area large enough to reflect all of the image light reflected from the curved mirror 32 toward the split reflection array 317.

The split reflection array 317 is formed between one side of the wedge prism 315 and the second surface 313, and is formed in a sawtooth shape in the lateral direction of the waveguide 31, in the front direction as seen by the user 15. In , they are expressed as vertical and mutually parallel lines. As shown in FIG. 5, the split reflection array 317 of the sawtooth structure is composed of an array of a transmission surface 324a through which the image light 37 transmits and a reflection surface 324b through which the image light 37 is reflected. And the transmitting surfaces 324a and reflecting surfaces 324b are installed parallel to each other.

The split reflection array 317 is implemented by combining female and male teeth. The waveguide 31 and the split reflection array 317 can each be manufactured through plastic injection molding. The split reflection array 317 is a separate component and has male teeth that can be shape-fitted to female teeth.

A polarization coating layer 325 whose degree of transmission or reflection varies depending on the incident angle of the image light 37 or the polarization component of the image light 37 is further provided between the female gear and the male gear. The polarizing coating layer 325 may be deposited on female teeth, or alternatively, may be deposited on male teeth. The polarization coating layer 325 has an angular deflection property that transmits the image light 37 on the surface at a small angle and reflects the image light 37 on the surface at a large angle.

When assembling the waveguide 31, the split reflection array 317 is completed by bonding it with a transparent optical adhesive. As the optical adhesive, a known adhesive can be used. Additionally, the waveguide 31, the split reflection array 317, and the optical adhesive use optical materials with the same refractive index.

In addition, the polarization reflection coating 316 and the polarization coating layer 325 on one side of the wedge prism 315 are configured to reflect the same polarization component, and the polarization coating layer 325 reflects the image light 37. At the same time, the external image 50 can be a partially reflective coating layer that can transmit.

In order for the center light of the image light 37 to be emitted vertically toward the eyes of the user 15, the following equation is satisfied,

Here, θ ₁ is the reflection angle of the split reflection array 317, and θ ₂ is the wedge angle formed by one side 315 of the wedge prism with the first surface 312 of the waveguide 31.

Operation of the first embodiment

Hereinafter, the operation of the first embodiment of the present invention will be described in detail with reference to the attached drawings. First, as shown in FIG. 1, image light 37 is output from the display panel unit 30. The image light 37 has a P-wave or S-wave component as it passes through the polarizer 301, and in this embodiment, it is configured to have a P-wave polarization component.

The image light 37 incident on the waveguide 31 is totally reflected by the first surface 312 and then passes through one side of the wedge prism 315 and the polarization reflection coating 316 to reach the end surface 314. For this purpose, the polarization reflection coating 316 is composed of a coating that transmits P waves.

The transmitted P-wave image light 37 passes through the λ/4 phase shift film 321, is converted into a circularly polarized light component, and is then reflected by the mirror coating of the curved mirror 32. The reflected image light 37 passes through the λ/4 phase shift film 321 and is once again phase-shifted by λ/4. Accordingly, the initially reflected image light 37 undergoes a final phase shift of λ/2 and is converted into an S-wave component. The image light 37 of the S-wave component is reflected by the polarization reflection coating 316 and transmitted to the split reflection array 317.

In other words, the image light 37 forms the primary exit pupil (first focus, F1) area before reaching the split reflection array 317, and then radiates again. The image light 37 is divided into several segments installed parallel to each other. It is divided and reflected by the reflection array 317 to form a secondary exit pupil (second focus, F2) in front of the eyeball of the user 15.

At this time, the split reflection array 317 is installed in an integrated sawtooth structure, and the sawtooth structure surface is coated with a polarizing coating that transmits the S-wave component when the angle of incidence is small and reflects it with a high reflectivity when the angle of incidence is greater than 40 degrees. By performing this, image light can be reflected with high efficiency. In addition, the polarization coating has the characteristic of being able to transmit the P wave component, which is the opposite polarization component, with high efficiency, thereby allowing the external image 50 to also reach the eyes of the user 15 with high efficiency. That is, the split reflection array 317 is provided with a polarizing coating layer 325 that reflects light with the same polarization component as the polarizing coating 316 applied to one side of the wedge prism 315, thereby increasing the light efficiency reflected to the user's eyes. can be maximized.

Figure 4 is a graph showing the optical characteristics of the functional polarizing coating layer 325 according to the present invention. As shown in Figures 4 and 5, the polarizing coating layer 325 applied to the sawtooth structure is mostly transmitted at small angles of incidence for S waves and has a very high reflectivity at angles where the angle of incidence is greater than 40 degrees. Therefore, when S-wave image light is induced, most of the image light is transmitted through a transmission surface with a small angle of incidence, and is reflected with a high reflectivity on a reflective surface with a large angle of incidence, reaching the user's eyes. At this time, in the case of P waves, the reflectance is very low at less than 50% at most angles of incidence from 0° to 80°, so most images incident as P waves can be transmitted.

Second Embodiment

Figure 2 is a configuration diagram of an image display device using a split reflection array and a wedge prism according to a second embodiment of the present invention. As shown in FIG. 2, the configuration of the display panel unit 30, the polarizer 301, the first and second surfaces 312 and 313 of the incident surface 311, the wedge prism 315, and the split reflection array 317. is the same as the first embodiment described above.

At the other end of the waveguide 31, a waveguide end surface 314 forming an end inclination angle θ _L is formed from the first surface 312. The end surface 314 forms a plane. The end surface inclination angle (θ _L ) may range from 50° to 80°, and the incident angle (θ _i ) of the incident surface 311 and the end surface inclination angle (θ _L ) are the same. A λ/4 phase shift film 321 is attached to the outer surface of the end surface 314, and a plano-convex lens 35 is attached to the outer surface of the λ/4 phase shift film 321. One side of the flat convex lens 35 is flat and is attached to the λ/4 phase shift film 321, and the other side forms the curved surface 355 of the convex lens. And, the curved surface 355 of the convex lens has a mirror surface so that the image light 37 is reflected. Additionally, the plano-convex lens 35 has a curvature that allows the totally reflected image light 37 to form a first focus F1 within the waveguide 31.

That is, the plano-convex lens 35 is integrated and disposed on the end surface 314 of the waveguide 31, so that a means for magnifying the image light 37 can be placed close to the user's pupil, thereby providing a wide viewing angle. It provides a structure that is advantageous for forming and at the same time minimizes the size and volume of the incident area.

The operation and optical path of this second embodiment are the same as those of the first embodiment, respectively.

A detailed description of preferred embodiments of the invention disclosed above is provided to enable any person skilled in the art to make or practice the invention. Although the present invention has been described above with reference to preferred embodiments, those skilled in the art will understand that various modifications and changes can be made to the present invention without departing from the scope of the present invention. For example, a person skilled in the art may use each configuration described in the above-described embodiments by combining them with each other. Accordingly, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

The present invention may be embodied in other specific forms without departing from the spirit and essential features of the present invention. Accordingly, the above detailed description should not be construed as restrictive in all respects and should be considered illustrative. The scope of the present invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the present invention are included in the scope of the present invention. The present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. In addition, claims that do not have an explicit reference relationship in the patent claims can be combined to form an embodiment or included as a new claim through amendment after filing.

5: Light source output module,
10: light guide plate,
11: Light guide part,
12: Input diffraction optical element,
13: intermediate diffraction optical element,
14: Output diffraction optical element,
15: user,
30: display panel,
31: waveguide,
32: curved mirror,
35: plano-convex lens,
37: video light,
50: external image,
301: polarizer,
311: entrance surface,
312: first surface
313: second surface,
314: waveguide end face,
315: wedge prism,
316: Polarizing reflective coating,
317: Split reflection array,
321: λ/4 phase shift film,
324a: transparent surface,
324b: reflective surface,
325: Polarizing coating layer,
355: curved surface,
F1: first focus,
F2: second focus,
θ _i : angle of incidence,
θ ₁ : reflection angle,
θ ₂ : wedge angle,
θ _L : End surface inclination angle,
θ _o : minimum angle of incidence,
θ _c : critical angle of total reflection,
θ _sr : Reflection surface inclination angle,
θ _st : Transmission surface inclination angle.

Claims (12)

In the image display device,
A display element 30 that generates image light 37;
A polarizer 301 faces the display element 30 in parallel and determines a polarization component of S-pol or P-pol; and
It is provided on one side of the polarizing plate 301, and the image light 37 that passes through the polarizing plate 301 is incident, and the exit pupil of the incident image light 37 is expanded in the first direction to user 15. ) and a waveguide 31 that emits to the side,
The waveguide 31 is,
The image light 37 is incident and totally reflected, and the first surface 312 and the second surface 313 are parallel to each other;
an incident surface 311 forming a predetermined incident angle θ _i with the first surface 312 at one end of the waveguide 31;
an end surface 314 forming an end inclination angle θ _L with the first surface 312 at the other end of the waveguide 31;
A phase shift film 321 attached to one side of the end surface 314;
A curved mirror 32 attached to one side of the phase shift film 321;
a wedge prism 315 installed inclined at a predetermined wedge angle (θ ₂ ) with the first surface 312;
Polarization reflective coating 316 attached to one side of the wedge prism 315;
A transmission surface 324a provided on one side of the wedge prism 315 and the second surface 313, through which the image light 37 reflected from the wedge prism 315 passes, and the transmitted image light A split reflection array (317) in which reflective surfaces (324b) reflecting (37) are alternately provided to form a sawtooth structure; and
A polarizing coating layer 325 formed on the sawtooth structure and having angular deflection to exhibit different reflectance depending on the angle of incidence on the transmission surface 324a or the reflection surface 324b,
An image display device using a split reflection array and a wedge prism, wherein the incident angle (θ _i ) and the inclination angle (θ _L ) are the same. In the image display device,
A display element 30 that generates image light 37;
A polarizer 301 faces the display element 30 in parallel and determines a polarization component of S-pol or P-pol; and
It is provided on one side of the polarizing plate 301, and the image light 37 that passes through the polarizing plate 301 is incident, and the exit pupil of the incident image light 37 is expanded in the first direction to user 15. ) and a waveguide 31 that emits to the side,
The waveguide 31 is,
The image light 37 is incident and totally reflected, and the first surface 312 and the second surface 313 are parallel to each other;
an incident surface 311 forming a predetermined incident angle θi with the first surface 312 at one end of the waveguide 31;
an end surface 314 forming an end inclination angle θ _L with the first surface 312 at the other end of the waveguide 31;
A phase shift film 321 attached to one side of the end surface 314;
A flat convex lens 35 attached to one side of the phase shift film 321;
a wedge prism 315 installed inclined at a predetermined wedge angle (θ ₂ ) with the first surface 312;
Polarization reflective coating 316 attached to one side of the wedge prism 315;
Provided on the second surface 313, a transmission surface 324a through which the image light 37 reflected from the wedge prism 315 transmits and a reflection surface 324b through which the transmitted image light 37 reflects ) are provided alternately to form a sawtooth structure (317); and
A polarizing coating layer 325 formed on the sawtooth structure and having angular deflection to exhibit different reflectance depending on the angle of incidence on the transmission surface 324a or the reflection surface 324b,
An image display device using a split reflection array and a wedge prism, wherein the incident angle (θ _i ) and the inclination angle (θ _L ) are the same. According to claim 1,
The end surface 314 and the curved mirror 32 have a split reflection array characterized in that the total reflected image light 37 has a curvature to form a first focus F1 within the waveguide 31. Image display device using wedge prism. According to claim 2,
The end surface 314 is flat,
An image display device using a split reflection array and a wedge prism, wherein the plano-convex lens (35) has a mirror surface to reflect the image light (37). According to claim 1,
An image display device using a segmented reflection array and a wedge prism, wherein the curved mirror (32) has a mirror surface to reflect the image light (37). The method of claim 1 or 2,
An image display device using a split reflection array and a wedge prism, wherein the phase shift film 321 is a λ/4 phase shift film 321. The method of claim 1 or 2,
An image display device using a split reflection array and a wedge prism, wherein the polarization reflection coating 316 and the polarization coating layer 325 reflect the same polarization component. delete The method of claim 1 or 2,
In order for the image light 37 to be totally reflected in the first surface 312, the minimum angle of incidence (θ ₀ ) of the image light 37 satisfies the following equation,

Here, n is the refractive index of the waveguide 31, and θ _c is the critical angle for total reflection. An image display device using a split reflection array and a wedge prism. The method of claim 1 or 2,
In order for the center light of the image light 37 to be emitted vertically toward the eyes of the user 15, the following equation is satisfied,

Here, θ ₁ is the reflection angle of the split reflection array 317 and θ ₂ is the wedge angle of the wedge prism 315. An image display device using a split reflection array and a wedge prism. The method of claim 1 or 2,
An image display device using a split reflection array and a wedge prism, wherein the polarization coating layer 325 is a partially reflective coating layer capable of reflecting the image light 37 and transmitting an external image 50 at the same time. 3. Splitting according to claim 1 or 2, wherein the image display device has a coaxial optical structure so that the central light of the image light (37) is emitted vertically toward the eyes of the user (15). Image display device using a reflection array and wedge prism.

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