KR102072012B1 - Head mounted display device - Google Patents

Abstract

The present invention relates to a head mounted display device capable of providing virtual reality or augmented reality to both eyes of a user using only one reflective display. More specifically, the head mounted display device comprises: a backlight generating light; a first polarization separator polarizing and emitting light emitted from the backlight; a reflective display generating an image by reflecting the polarized light in the first polarization separator; a second polarization separator separating light emitted from the reflective display in accordance with a polarization state; and a first prism module and a second prism module respectively arranged on a path of light separated in accordance with the polarization state in the second polarization separator to enlarge and guide the light.

Description

HEAD MOUNTED DISPLAY DEVICE}

The present invention relates to a head mounted display device for smart glasses used to simultaneously or selectively implement augmented reality and virtual reality, and in particular, by providing content to both eyes simultaneously while using one display element, The present invention relates to a head mounted display device capable of lowering manufacturing costs and reducing user fatigue and dizziness.

Virtual Reality (VR) is a technology that creates a virtual environment and makes it feel like reality, and Augmented Reality (AR) is a technology that expresses virtual information on the surrounding environment that is actually visible. (AR) and Virtual Reality (VR) are a concept of Reality-Virtuality Continuum that combines reality and virtual information simultaneously to build an environment, Mixed Reality (MR), Augmented Virtual (AV) ) Is developing in the form.

Recently, smart glasses that can provide such virtual reality or augmented reality to users are widely used not only in the industrial field but also in various external activities such as games and leisure.

The head mounted display is mounted on a frame of a smart glass having an appearance similar to that of glasses, and provides contents such as an image to be delivered to a user. The head mounted display is made of a display element and a display element that produce an image to be used in virtual reality or augmented reality. It is common to include various optical systems for delivering an image to the user's eyes. In conventional smart glasses using a head mounted display, two or more display elements are generally used to provide an image to both eyes of a user. That is, a method of generating an image for providing to each eye through a separate display element and transferring the generated image to each eye is common.

As a result, a large number of display elements are required to produce an image to be simultaneously provided to both eyes, resulting in an increase in manufacturing costs, and a complicated structure for placing a large number of parts, resulting in complexity and yield of a manufacturing process. There was a problem that a decrease occurs.

Furthermore, since the images provided to each eye are generated by separate display devices, color differences such as white balance, saturation, and chromaticity, which are inevitably generated according to the characteristics of the display devices, are generated, and thus the brightness is different. There was a problem causing discomfort and dizziness, and there was a problem that a higher cost was required to eliminate the difference between the images provided to the two eyes.

On the other hand, as a result of the use of multiple display elements, if a failure occurs in any one of the display elements, this immediately leads to a failure of the entire device, thereby reducing the life of the product.

Republic of Korea Patent Publication No. 10-2015-0062222 (2015.06.08)

An object of the present invention is to provide a head mounted display device capable of providing virtual reality or augmented reality to both eyes while using only one display device.

In addition, the present invention provides a head-mounted display device that can reduce the discomfort and dizziness of the user caused by the conventional method using a plurality of display devices by providing the same image generated in one display device to both eyes at the same time It aims to provide.

Head mounted display device according to the present invention, the backlight for generating light; A first polarization separator that polarizes the light emitted from the backlight and emits the light; A reflective display configured to reflect light polarized by the first polarizer to generate an image; A second polarization separator for separating light emitted from the reflective display according to a polarization state; And a first prism module and a second prism module respectively disposed on the paths of the light separated by the polarization state in the second polarizer to enlarge and guide the light.

The head mounted display device according to the present invention may further include a first collimating lens and a second collimating lens for making the light incident on the first prism module and the second prism module into parallel light.

Each of the first prism module and the second prism module includes three wedge prisms having an inclined surface, wherein the first wedge prism receives the parallel light emitted from each collimating lens and expands in a horizontal direction. And a second wedge prism and an inclined surface that receives light enlarged in the horizontal direction by the wedge prism and expands in a vertical direction to be emitted to face the inclined surface of the second wedge prism.

The head mounted display device according to the present invention further includes a first phase delay plate for changing the polarization state of the light reflected from the reflective display, and the light reflected from the reflective display passes through the first phase delay plate. The polarization state may be changed and then transferred to the second polarization separator.

The second polarization splitter may reflect light of a first polarization component in a first lateral direction, transmit light of a second polarization component, and transmit the light reflected in the first lateral direction to the first prism module. It can be characterized by.

The head mounted display device according to the present invention may further include a mirror that reflects the light transmitted through the second polarizer and guides it back to the second polarizer, and is disposed between the second polarizer and the mirror, The display device may further include a second phase delay plate configured to change a polarization state of light reflected from the mirror and transmitted to the second polarization separator.

The light reflected from the mirror and guided to the second polarizer may be reflected by the second polarizer to the second lateral direction and transmitted to the second prism module.

Since the head mounted display device according to the present invention generates an image using only one reflective display, there is an advantage of preventing discomfort and dizziness of a user generated in a conventional head mount display device using a plurality of displays. .

In particular, the number of displays is reduced, manufacturing costs are reduced, and the configuration of the device is simplified, making it easy to manufacture and reducing the weight of the device has the advantage of enabling more convenient use.

1 is a block diagram of a head mounted display device according to the present invention.
2 is a block diagram of a prism module according to the present invention.
3 is a conceptual diagram illustrating a process of expanding as light is reflected from an inclined surface of the wedge prism.
Figure 4 shows the structure of the wedge prism formed with the saw-toothed expansion means according to the present invention.
5 is a partial configuration diagram of a head mounted display device including a shade according to the present invention.
6 is a block diagram of a shade according to the present invention.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all transformations, equivalents, and substitutes included in the spirit and scope of the present invention.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present invention, the terms 'comprise' or 'having' are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a head mounted display device 100 according to the present invention. As shown in FIG. 1, the head mounted display device 100 according to the present invention includes a backlight 1, a polarizer 2, 5, a reflective display 3, a phase delay plate 4, 11, and a prism. Modules 6, 8, mirrors 7 and collimating lenses 9, 10. That is, in the head mounted display apparatus 100 according to the present invention, images provided to both eyes of the user are generated in one reflective display 3 disposed at the center portion.

The image generated by one reflective display 3 disposed in the center portion is then branched by different polarizers 2 through different paths and guided through a pair of optical systems arranged symmetrically with respect to the center portion. It is delivered to both eyes of the user. Referring to FIG. 1, the optical system may mean collimating lenses 9 and 10, prism modules 6 and 8, and screen magnification lenses 15, but may include additional optical elements as necessary. .

In FIG. 1, the backlight 1 refers to a light source, and may be an LED backlight that may sequentially generate RGB light.

The polarization splitters 2 and 5 are optical elements for separating the input light according to the polarization state, and may be polarization beam splitters. That is, the polarization separators 2 and 5 transmit the polarization components of any one of the polarization components constituting the input light as they are, but the other polarization components are perpendicular to each other, that is, the light is directed to the polarization separators 2 and 5. The light is reflected laterally at a right angle with respect to the incident direction. Therefore, the light incident on the polarization separators 2 and 5 splits into two paths depending on the polarization state.

In general, light that is not polarized includes a first polarization component and a second polarization component. The first polarization component may mean P-polarized light, and the second polarization line may mean S-polarized light. On the contrary, the first polarization component may mean S-polarized light and the second polarization line may mean P-polarized light. When light including both the first polarization component and the second polarization component is incident on the polarization separators 2 and 5, the first polarization component is transmitted as it is, and the second polarization component is reflected in the perpendicular direction.

The phase delay plates 4 and 11 are optical elements for changing the polarization state of incident light and may be λ / 4 wave plates. That is, the light in the linearly flat state is converted into circularly polarized light while passing through the phase delay plates 4 and 11, and the light in the circularly polarized state is converted into the linearly polarized state when passing through the phase delay plates 4 and 11.

The light generated and emitted from the backlight 1 is incident on the first polarizer 2. The light generated and emitted from the backlight 1 is generally not polarized in a specific direction and includes both a first polarization component and a second polarization component. The first polarizer 2 polarizes the incident light and transmits the incident light to the reflective display 3. That is, with respect to the incident light, only one polarization component is reflected in the perpendicular direction and transmitted to the reflective display 3. The reflective display 3 is a display in which an image is generated using external light, and may be a liquid crystal on silicon (LCoS).

The light emitted from the reflective display 3 is incident to the first phase delay plate 4 through the first polarization separator 2, and the polarization state is converted and output through the first phase delay plate 4. . The light emitted from the reflective display 3 and incident on the first phase delay plate 4 may be in a linearly polarized state, and the polarization state may be changed in the first phase delay plate 4 to be emitted in a circularly polarized state. Light emitted from the first phase delay plate 4 is transmitted to the second polarization separator 5.

The light incident on the second polarization separator 5 branches back to two paths according to the polarization state. That is, as in the first polarizer 2, the second polarizer 5 transmits one polarization component as it is, but reflects the other polarization component in a right angle direction.

The second polarization separator 5 reflects the light of the first polarization component in the first lateral direction and transmits the light of the second polarization component as it is. Referring to FIG. 1, the first lateral direction may mean a direction perpendicular to the left side with respect to the direction in which light is incident on the second polarization separator 5. Light of the first polarization component reflected in the first lateral direction is transmitted to the first prism module 6 via the first collimating lens 9.

On the other hand, the light of the second polarization component transmitted through the second polarization separator 5 as it is is transmitted to the mirror 7 via the second phase delay plate 11. The mirror 7 reflects the incident light and guides it back to the second polarization separator 5. The light of the second polarization component having passed through the second polarization separator 5 as it is has a linear flat state. Therefore, it is converted into a circularly polarized state while passing through the second phase delay plate 11. The light transmitted through the second phase delay plate 11 may have a circularly polarized state rotating in a clockwise direction, but may have a circularly polarized state rotating in a counterclockwise direction.

When the light in the circularly polarized state is reflected by the mirror 7, the circularly polarized state is maintained but the direction of rotation is reversed. That is, when light in a circularly polarized state rotating clockwise is incident on the mirror 7 and reflected, the reflected light is in a state rotating in the counterclockwise direction. On the contrary, when the light in the circularly polarized state rotating in the counterclockwise direction is incident on the mirror 7 and reflected, the reflected light is in the state rotating in the clockwise direction.

The light in the circularly polarized state, which is reflected by the mirror 7 and whose rotation direction is reversed, is converted into the linearly polarized state while passing through the second phase delay plate 11. Thereafter, the light is incident on the second polarization separator 5 and then reflected in the orthogonal direction and proceeds in the second lateral direction, and is transmitted to the second prism module 8 through the second collimating lens 10. In this case, the second lateral direction is a direction forming an angle of 180 ° with the first lateral direction, and thus, the first lateral direction and the second lateral direction mean directions opposite to each other.

Therefore, in the head mounted display device 100 according to the present invention, the polarizers 2 and 5 and the phase delay plates 4 and 11 in which the image generated by the reflective display 3 placed in the center are arranged in a straight line. And collimating lens (9, 10), prism module (6, 8), screen magnification lens (15) which are separated into two paths while passing through the mirror and the mirror (7). It is enlarged while going through the exit.

The first collimating lens 9 and the second collimating lens 10 disposed in front of the first prism module 6 and the second prism module 8 on the optical path adjust the incident light to parallel light. send. In other words, light passing through a plurality of optical systems is generally spread as it progresses. The first collimating lens 9 and the second collimating lens 10 reduce the aberration of the spread light and convert the light into parallel light. Light adjusted to parallel light by the first collimating lens 9 and the second collimating lens 10 is incident on the first prism module 6 and the second prism module 8, respectively.

2 is a configuration diagram of the prism modules 6 and 8 according to the present invention. The prism modules 6 and 8 are optical modules for guiding the user's eyes while enlarging light, and each prism module 6 and 8 has three wedge prisms 12, 13 and 14 as shown in FIG. ) And a magnification lens 15. Each wedge prism 12, 13, 14 is formed in a structure having an inclined surface. Light passing through the collimating lenses 9 and 10 is incident on the first wedge prism 12. Light incident on the first wedge prism 12 is reflected on the inclined surface of the first wedge prism 12 and is incident on the magnifying lens 15.

3 is a conceptual diagram illustrating a process of expanding while reflecting light from an inclined surface of the first wedge prism 12. As illustrated in FIG. 3, light incident to the first wedge prism 12 passes through the first wedge prism 12 and enters the inclined surface of the first wedge prism 12, and is reflected at the inclined surface. In this case, as shown in FIG. 3, when the light incident on the first wedge prism 12 is changed in position on the cross section of the light, the position on the inclined surface where reflection occurs is changed, and as a result, the light is enlarged in the first direction. do. The first direction means the same direction as the direction in which the inclined surface of the wedge prism extends while inclining.

As shown in FIG. 2, the extending direction of the inclined surface formed on the first wedge prism 12 and the extending direction of the inclined surface formed on the second wedge prism 13 are perpendicular to each other. Accordingly, the first wedge prism 12 enlarges the incident light in the first direction, and the second wedge prism 13 enlarges the light in the same manner as the first wedge prism 12, but the enlargement direction is the first It becomes a 2nd direction orthogonal to a direction. The enlarged image is passed through the first wedge prism 12 and the second wedge prism 13 to the user's eyes. Subsequently, the first direction in the process of explaining the enlargement of light in the first and second wedge prisms 12 and 13 with reference to FIGS. 2 and 3 is referred to as a horizontal direction, and the second direction as a vertical direction. Do it.

Magnifying means may be formed on the inclined surfaces of the first wedge prism 12 and the second wedge prism 13, respectively. The expanding means may be a holographic optical element (HOE), and the holographic optical element may be formed by processing a slope of the first wedge prism 12 or the second wedge prism 13 with a laser. . As shown in FIG. 4, the expanding means may have a form in which the inclined surface is processed into a sawtooth shape. The expanding means corrects the path of the light so that the light reflected from the inclined surface can be incident perpendicularly to the bottom surface of the first wedge prism 12 and the second wedge prism 13. Meanwhile, in order to maintain the magnification of the original image during the magnification of the first wedge prism 12 and the second wedge prism 13, the inclined surfaces of the first wedge prism 12 and the second wedge prism 13 are bottomed. It is preferable that the inclination angle which forms a surface is the same.

As shown in FIG. 2, the magnifying lens 15 may be disposed between the first wedge prism 12 and the second wedge prism 13. The magnification lens 15 is an optical element for additionally enlarging the light transmitted through the first wedge prism 12. A lens for enlarging the light in one of the vertical direction and the horizontal direction may be used, and the horizontal and vertical directions may be used. As such, a lens that simultaneously enlarges the same magnification may be used. The light passing through the magnifying lens 15 is incident on the second wedge prism 13 and is enlarged in the vertical direction while being reflected from the inclined surface of the second wedge prism 13. As illustrated in FIG. 2, the third wedge prism 14 is disposed such that the inclined surface faces the inclined surface of the second wedge prism 13. The inclined surfaces of the third wedge prism 14 and the second wedge prism 13 may be disposed to abut each other. The third wedge prism 14 is to prevent distortion of an image, and the inclined surface of the third wedge prism 14 may vary depending on the shape of the enlargement means formed on the inclined surface of the second wedge prism 13. That is, when the vertical diffusion means formed in the second wedge prism 13 is a holographic optical element, the inclined surface of the third wedge prism 14 may be a plane. If the diffusion means formed on the second wedge prism 13 is a serrated surface, the inclined surface of the third wedge prism 14 may engage with the saw tooth shape formed on the inclined surface of the second wedge prism 13. It may be shaped. That is, the inclined surface of the third wedge prism 14 is formed in the same shape as the sawtooth formed on the surface of the inclined surface of the second wedge prism 13, but is formed to have an inverse phase so that the second and third wedge prism 13, 14 The sawtooth shape formed on the inclined surface of the can be formed to mesh with each other.

As shown in FIG. 5, the head mounted display apparatus 100 according to the present invention may include a shade 20 capable of transmitting or blocking external light. Shade 20 is a shield composed of a translucent or light diffusing material and may be formed of a plastic LCD. 6 is a detailed configuration diagram of the shade 20 formed of the plastic LCD.

As shown in FIG. 6, the shade 20 includes an upper flexible transparent film 21 on which the upper transparent electrode 23 is formed, a lower flexible transparent film 22 on which the lower transparent electrode 24 is formed, and an upper transparent. The liquid crystal layer 25 formed between the electrode 23 and the lower transparent electrode 24, the sealant 26 used to seal the LCD panel, and the spacer 27 maintaining the gap of the liquid crystal layer 25 therein. The connector 28 may include an electrical signal applied to the upper transparent electrode 23 and the lower transparent electrode 24.

The transparent electrodes 23 and 24 may function as a screen or a lens of the head mounted display device 100, and the upper and lower flexible transparent films 21 and 22 may be used as plastic substrates.

A flexible transparent film (21, 22) is a polycarbonate (PC), polyimide (PI), and a transparent plastic material having an isotropic, such as cyclo-olefin polymer (COP) can be used, 10 ^-3 g / day to 10 ^{- It} can have a moisture permeability of ⁶ g / day. It is preferable that the thickness of the flexible transparent films 21 and 22 is 30-300 micrometers, and the transparent electrodes 23 and 24 are formed in one surface.

The transparent electrodes 23 and 24 may be formed of metal oxides such as ITO, IZO, and AZO. The transparent electrodes 23 and 24 preferably have a transmittance of 80% or more for light having a wavelength of 550 nm, and a thickness of 5 to 500 nm.

The sealant 26 may be formed of a single layer of organic or inorganic thin film or a laminate thereof, wherein the inorganic thin film layer used may be formed by sputtering, PECVD or PEALD, and the organic thin film layer may be a doctor blade, spin coating, or gravure coating. It can be formed by various organic film forming methods, such as printing. As the material of the inorganic thin film layer, SiO ₂ , Al ₂ O ₃ , SiNX, SiC, SiOC, SiON, or the like may be used. The thickness of the inorganic thin film layer is preferably 5 to 1000 nm. As the material of the organic thin film layer, a Si-based compound, an acrylic, or a urethane may be used, and the thickness is preferably 5 to 5000. On the other hand, the spacer 27 is preferably formed to have a thickness of 5㎛ or less. The shade 20 having the above-described structure is disposed in front of the second wedge prism 13, as shown in Figure 5 both eyes It is arranged one by one in front. The shades 20 arranged one by one in front of both eyes may be controlled to independently transmit or block light. That is, the image generated by the head mounted display device according to the present invention may be controlled to be delivered to only one of both eyes of the user. As such, if the image is transmitted to only one side of the user while rapidly changing the light transmission or blocking state of the shade 20, the user will eventually see the 3D image.

Meanwhile, although FIG. 5 illustrates a case where the shade 20 is disposed in front of the second wedge prism 13, the 3D image may be realized by moving the shade 20 to various positions on the optical path. For example, the light incident on the magnification lens 15 or the light emitted from the magnification lens 15 may be transmitted to be disposed in front of or behind the magnification lens 15. It may also be arranged in front of or behind the first and second collimating lenses 9, 10. That is, as long as the position on the optical path in which the final polarization state where the light is incident to both eyes of the user is maintained, it may be variously arranged to provide a 3D image.

As mentioned above, although the invention which concerns on this invention was demonstrated concretely according to the Example, this invention is not limited to the said Example, Of course, various deformation | transformation is possible in the range which does not deviate from the summary of invention.

1: backlight 2: first polarizer
3: reflective display 4: first phase delay plate
5: second polarization separator 6: first prism module
7 mirror 8 second prism module
9: first collimating lens 10: second collimating lens
11: second phase delay plate 12: first wedge prism
13: 2nd Wedge Prism 14: 3rd Wedge Prism
15: magnifying lens 20: shade
21: upper flexible transparent film 22: lower flexible transparent film
23: upper transparent electrode 24: lower transparent electrode
25 liquid crystal layer 26 sealant
27: spacer 28: connector
100: head mounted display device

Claims (6)

A backlight generating light;
A first polarization separator that polarizes the light emitted from the backlight and emits the light;
A reflective display configured to reflect light polarized by the first polarizer to generate an image;
A second polarization separator for separating light emitted from the reflective display according to a polarization state;
A first prism module and a second prism module respectively disposed on the paths of the light separated by the polarization state in the second polarizer to enlarge and guide the light;
A first phase delay plate provided between the first polarizer and the second polarizer to change a polarization state of light reflected by the reflective display;
A mirror which reflects the light transmitted through the second polarizer and enters the second polarizer in a state in which the rotation direction of the light is reversed;
A second phase delay plate provided between the second polarizer and the mirror to change the polarization state of the light passing through the second polarizer and to change the polarization state of the light reflected from the mirror and incident on the second polarizer;
An enlarged lens provided on each of the optical paths of the first prism module and the second prism module to enlarge light;
And a shade for generating a 3D image by providing light of the final polarization state emitted from the second polarization separator onto a path of light incident to both eyes of a user.
The method of claim 1,
And a first collimating lens and a second collimating lens for converting the light incident to the first prism module and the second prism module into parallel light.
The method of claim 2,
The first prism module and the second prism module includes three wedge prisms each having an inclined surface,
A first wedge prism that receives the parallel light emitted from each collimating lens and expands it in a horizontal direction, and a second wedge that receives light extended in the horizontal direction by the first wedge prism and expands it in a vertical direction And a third wedge prism disposed such that the prism and the inclined surface face the inclined surface of the second wedge prism.
delete The method of claim 1,
And the second polarization separator reflects light of the first polarization component in a first lateral direction and transmits light of the second polarization component.
delete

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