KR20180020768A - Display module and display device for virtual reality - Google Patents

Abstract

The present invention provides an optical output module providing an image which removes a black matrix. According to an embodiment of the present invention, the optical output module comprises: a plurality of light sources separated from each other; and a diffraction grid located on an upper side of the light source. The diffraction grid includes an incident surface on which light emitted from the light source is incident and an exit surface to which the light incident on the incident surface is emitted. A plurality of optical path conversion units having a mountain shape is formed on the exit surface of the diffraction grid. Also, the optical output module satisfies condition equation 1 of (λ*T)/D < P < (3*λ*T)/D.

Description

TECHNICAL FIELD [0001] The present invention relates to an optical output module and a virtual reality display device,

This embodiment relates to an optical output module and a virtual reality display device.

The virtual reality display device is a device that a user wears like a pair of glasses and can view an image, and may be referred to as a head mount display (Head Mounted Display) or an FMD (Face Mounted Display).

Although these spectacular type monitors were first developed for military use, they began to be used for military purposes. However, due to various factors such as high performance and miniaturization of computer system, development of display devices such as LCD, and development of image and communication technology, .

Especially, with the development of wearable computers and smart phones, it is expected that the spread of eyeglass type monitors as personal display devices for wearable computers is expected to increase.

There is a problem that the pixel boundary (black matrix) of the optical output module is visually recognized due to the high magnification of the lens in the image of the virtual reality display device which is being studied recently. In this case, the resolution is lowered and the user's feeling of immersion is further reduced.

The present embodiment is to provide an optical output module that provides an image from which a pixel boundary (black matrix) is removed. That is, the present embodiment provides an optical output module including a de-pixelization system.

Also, a virtual reality display device including the optical output module is provided.

The optical output module according to the present embodiment includes a plurality of light sources arranged to be spaced apart from each other; And a diffraction grating disposed on the upper side of the light source, wherein the diffraction grating includes an incident surface on which light emitted from the light source is incident and an exit surface on which light incident on the incident surface is emitted, A plurality of optical path changing units each having a mountain shape are formed on the emitting surface of the light source, and the following conditional expression can be satisfied.

<Conditional expression>

(? * T) / D <P <(3 *? * T) / D

Where P is the shortest distance between adjacent ridges of the plurality of optical path changing units, lambda is the wavelength of the light emitted from the light source, T is the distance from the light source to the ridgeline of the optical path changing unit closest to the light source, and D Is a distance between the nearest light sources among the plurality of light sources.

The distance from the exit surface of the light source to the ridge of the optical path changing unit may be 0.01 to 20 mm.

The plurality of light sources may include a red light source, a green light source, and a blue light source.

The light source may be disposed apart from the diffraction grating.

Wherein the light output module provides an image to a user and the plurality of light sources comprises a first light source and a second light source spaced apart from the first light source and the diffraction grating comprises a first diffraction The light can be formed by the user to be recognized as being emitted between the first and second light sources.

The diffraction grating may be formed to remove the black matrix recognized by the user as the plurality of light sources are spaced apart.

Lambda of the above conditional formula may be a green wavelength band.

Lambda of the conditional expression may be an average of the wavelengths of the plurality of light sources.

The distance between the light sources may be a distance between the centers of the light sources.

According to another aspect of the present invention, there is provided a light output module comprising: a plurality of light sources arranged to be spaced apart from each other; And a diffraction grating disposed on the upper side of the light source, wherein the diffraction grating includes an incident surface on which light emitted from the light source is incident and an exit surface on which light incident on the incident surface is emitted, Wherein a distance from the light source to the ridgeline of the light path changing unit closest to the light source is set to be smaller than a distance from the light source to the ridge of the light path changing unit when the distance between the light sources is 20 to 50 m, The value divided by the shortest distance between adjacent ridges of the plurality of optical path changing units may be 16.129 to 55.556.

The virtual reality display apparatus according to the present embodiment includes a holder; A light output module disposed in the holder and outputting a virtual reality image; And a lens module disposed in the holder and spaced apart from the optical output module, wherein the optical output module comprises: a plurality of light sources arranged to be spaced apart from each other; And a diffraction grating disposed on the upper side of the light source, wherein the diffraction grating includes an incident surface on which light emitted from the light source is incident and an exit surface on which light incident on the incident surface is emitted, A plurality of optical path changing units each having a mountain shape are formed on the emitting surface of the light source, and the following conditional expression can be satisfied.

<Conditional expression>

(? * T) / D <P <(3 *? * T) / D

Where P is the shortest distance between adjacent ridges of the plurality of optical path changing units, lambda is the wavelength of the light emitted from the light source, T is the distance from the light source to the ridgeline of the optical path changing unit closest to the light source, and D Is a distance between the nearest light sources among the plurality of light sources.

And a lens moving unit for movably fixing the lens module to the holder.

The lens moving unit may be screwed to the holder.

Through this embodiment, an image in which the black matrix is removed can be obtained.

As a result, it is expected to improve the resolution and the immersion of the user.

1A and 1B are perspective views of a virtual reality display device according to the present embodiment.
2 is an exploded perspective view of a display assembly according to the present embodiment.
3A is a perspective view of a display assembly according to the present embodiment.
3B is a rear view of the display assembly according to the present embodiment.
Figs. 3C and 3D are views showing openings of a first area and a second area of the holder. Fig.
FIG. 4 is a diagram showing a part of the configuration of a virtual reality display device according to the present embodiment, together with the naked eye of a user.
5 is a conceptual diagram showing a part of the optical output module according to the present embodiment.
Figs. 6 to 8 are graphs showing the relationship between the distance between the ridges (x-axis) of the plurality of optical path changing units and the distance between the plurality of light sources (y-axis) in this embodiment. 6 shows a case where the distance from the exit surface of the light source to the ridgeline of the optical path changing unit is 1 mm, Fig. 7 shows the case where the distance from the exit surface of the light source to the ridge of the optical path changing unit is 0.5 mm, Shows a case where the distance from the exit surface of the light source to the ridgeline of the optical path changing unit is 0.25 mm.

Hereinafter, some embodiments of the present invention will be described with reference to exemplary drawings. In describing the components in the drawings, the same components are denoted by the same reference numerals whenever possible, even if they are displayed on other drawings.

In describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected, coupled, or connected to the other component, It is to be understood that another element may be "connected &quot;," coupled &quot;, or "connected" between elements.

Hereinafter, a configuration of a virtual reality display device according to the present embodiment will be described with reference to the drawings.

1A and 1B are perspective views of a virtual reality display device according to the present embodiment.

The virtual reality display device 10 according to the present embodiment may include a front shield 11, a main body 12, and a side shield 13. At least one of the front shield 11, the main body 12 and the side shield 13 may be omitted or changed in the virtual reality display device 10 according to the present embodiment. The virtual reality display apparatus 10 according to the present embodiment may include a main body 12 and a pair of display assemblies 1000 disposed on the main body 12. [

The front shield 11 may be disposed on the front face of the virtual reality display device 10. An optical output module 800 to be described later may be disposed inside the front shield 11.

A pair of display assemblies 1000 may be disposed on one side of the main body 12. [ Between the pair of display assemblies 1000, a first support unit 14 supported by the wearer's nose can be disposed. The side shield 13 may be disposed at the edge of the main body 12. A front shield 11 may be disposed on the other side of the main body 12. [ The user wearing the virtual reality display device 10 can clearly see the image displayed on the optical output module 800 without the influx of external light by the action of the front shielding part 11 and the side shielding part 13 .

The main body 12 acts as a frame of the virtual reality display device 10, so that it can be formed of a material having high strength and not breaking. The main body 12 may be made of a material such as metal or ceramics.

The front shield 11 provided on the front surface of the main body 12 and the side shield 13 provided on the rear side of the main body 12 may be provided with a material and shape that can shield light from the outside. Particularly, the side shield 13 is formed with a groove g and can be supported by the wearer's nose.

The side shield 13 may be disposed on the rear side of the virtual reality display device 10. The face of the user can be brought into contact with the side shield 13.

A second support unit 15 connected to the body 12 or the side shield 13 and supported on the wearer's ear may be disposed outside the pair of display assemblies 1000. [

The first cable 16 may be connected to the display assembly 1000. The first cable 16 may supply a driving signal or the like to the optical output module 800 in the display assembly 1000.

The second cable 18 can be connected to the main body 12. The second cable 18 can supply current to the virtual reality display device 10 from the outside. The virtual reality display device 10 according to the present embodiment can be implemented with a light weight because the power source is provided externally. The first cable 16 and the second cable 18 may be, for example, USB (Universal Serial Bus).

Hereinafter, a configuration of a display assembly according to the present embodiment will be described with reference to the drawings.

FIG. 3 is a perspective view of the display assembly according to the present embodiment, FIG. 3B is a rear view of the display assembly according to the present embodiment, FIGS. And the openings of the first area and the second area of the holder.

The display assembly 1000 according to the present embodiment includes a lens cover 100, a fixing ring 200, a lens module 300, a lens moving unit 400, a stopper 500, a holder 600, A fixed unit 700, an optical output module 800, and a protection unit 900. In the display assembly 1000 according to the present embodiment, the lens cover 100, the fixing ring 200, the lens module 300, the lens moving unit 400, the stopper 500, the holder 600 , The fixed unit 700, the optical output module 800, and the protection unit 900 may be omitted or changed.

The lens cover 100 can prevent foreign matters from being adhered to the surface of the lens module 300, scratches or the like. The lens cover 100 may separate the virtual reality display device 10 from the display assembly 1000 when the user is using the device.

The stationary ring 200 may be disposed at the edge of the lens module 300 inserted into the lens moving unit 400. The fixed ring 200 can be inserted between the lens module 300 and the lens moving unit 400 at the edge. The fixing ring 200 may prevent the lens module 300 from being detached from the lens moving unit 400.

The lens moving unit 400 may be movably coupled to the holder 600. [ The lens moving unit 400 can house the lens module 300 on the inner side. The lens module 300 may be coupled to the lens moving unit 400. The lens moving unit 400 can be screwed to the holder 600. [ A plurality of patterns 410 may be disposed on the outer circumferential surface of the lens moving unit 400. The pattern 410 may be a shape in which the surface of the lens moving unit 400 protrudes or is depressed. The pattern 410 can be used when the wearer grips and rotates the lens shift unit 400 to approach the holder 600 or move it away from the holder 600. That is, the user rotates the lens moving unit 400 to move the lens module 300, thereby moving the image transmitted from the optical output module 800 through the lens module 300 to the eye of the wearer (See FIG. 4). The pattern 410 may be provided on the outer peripheral surface of the lens moving unit 400. At this time, the first screw thread 420 may protrude from the lower portion of the outer circumferential surface of the lens moving unit 400. The stopper 500 may be disposed at the edge of the coupling region of the lens moving unit 400 and the holder 600. [ The fixing ring 200 may be disposed at the edge of the lens module 300 inserted into the lens moving unit 400.

The stopper 500 may be disposed between the holder 600 and the lens moving unit 400. The stopper 500 can be fixed between the edge of the holder 600 and the edge of the lens moving unit 400. The diameter of the inner peripheral surface of the stopper 500 may be smaller than the diameter of the outer peripheral surface of the first screw thread 420 on the outer peripheral surface of the lens moving unit 400. [ In this case, even if the user continuously rotates the lens moving unit 400 in the separating direction, the lens moving unit 400 can be prevented from being separated from the holder 600.

The holder 600 may be a housing of the display assembly 1000. At least a part of the holder 600 may be provided in the form of a body tube. The optical output module 800 may be fixed to the lower surface of the holder 600 by a fixing member 700. The second screw thread 620 may be provided on the upper portion of the inner circumferential surface of the holder 600 in a recessed shape. The second threaded line 620 may be provided in a reverse phase of the first threaded line 420. When the lens moving unit 400 is rotated in the first direction by the engagement of the second screw thread 620 and the first screw thread 420, the lens moving unit 400 can be gradually inserted into the holder 600. At this time, the lens module 300 can access the optical output module 800. In addition, when the lens moving unit 400 is rotated in the second direction, the lens moving unit 400 can be gradually separated from the holder 600. [ At this time, the lens module 300 can be moved away from the optical output module 800. The holder 600 may include a sliding bar 650 exposed in both directions of the supporting plate 630 and the supporting plate 630. The holder 600 may be inserted with the lens moving unit 400 inserted therein.

The lower surface of the holder 600 may be provided in the form of a support plate 630. In this case, coupling with the optical output module 800 can be facilitated. The support plate 630 may be referred to as a mount portion in which the optical output module 800 is disposed. The support plate 630 may be disposed in a direction perpendicular to the optical axis of the lens module 300. The support plate 630 may have a rectangular shape in which the length in the lateral direction is larger than the length in the longitudinal direction. The support plate 630 may have a shape corresponding to the shape of the optical output module 800 or the fixed unit 700.

A pair of sliding bars 650 may be provided in the support plate 630 of the holder 600. The sliding bar 650 may protrude from both sides of the support plate 630. The sliding bar 650 may be inserted into a through hole (not shown) inside the support plate 630. In this case, the position of the lens unit 1000 can be moved by moving the support plate 630 with respect to the sliding bar 650. The position shifting function of the display assembly 1000 with respect to the sliding bar 650 can be used to adjust the distance between the pair of display assemblies 1000 according to the width of the wearer's forehead.

The fixing unit 700 can seal and fix the bottom of the second area of the holder 600 and the edge of the optical output module 800. Accordingly, the fixed unit 700 can block external light from entering the display assembly 1000. The fixing unit 700 may be a double-sided tape. The fixing member 700 may be open only in the center region and may be provided only in the edge region so that the image of the optical output module 800 is transmitted to the lens module 300. The center region of the holder 600 is also opened to transmit the image of the optical output module 800 toward the lens module 300.

The optical output module 800 may be fixed to the holder 600. The optical output module 800 can output a virtual reality image. In the optical output module 800, an optical output module 800 may be disposed below the holder 600. The optical output module 800 may display a moving image or a still image. The optical output module 800 may be, for example, a liquid crystal display (LCD). In addition, the optical output module 800 may be a display panel. The optical output module 800 may be provided as one unit. Alternatively, a pair of optical output modules 800 may be provided. In this case, each of the pair of optical output modules 800 can transmit the image to the left and right eyes of the user. The optical output module 800 may be fixed to the lower portion of the holder 600 through a fixing unit 700. The optical output module 800 may include a light source. At this time, the light source may be a light emitting diode.

The protection unit 900 may be provided under the optical output module 800. The protection unit 900 supports the optical output module 800 and can fix a PCB or a flexible printed circuit board (FPCB) (not shown) of the optical output module 800. The protection unit 900 may be provided with a circuit board 850. The circuit board 850 may be an FPCB (Flexible Printed Circuit Board).

The virtual reality display device 10 may be provided with a pair of lens modules 300 and a pair of optical output modules 800. In another embodiment, a pair of lens modules 300 and one optical output module 800 may be provided. When a pair of lens modules 300 are divided into a first lens module and a second lens module and a pair of optical output modules 800 are divided into a first optical output module and a second optical output module, The image of the output module may be outputted through the first lens module and the image of the second optical output module may be outputted through the second lens module.

The area where the lens module 300 is arranged in the holder 600 can be referred to as a first area. The lens moving unit 400 may be disposed in the first area. In the first region, a hollow opening may be formed in the holder 600. The hollow shape formed in the first region may be a circular opening. The area in the direction from the holder 600 toward the optical output module 800 can be referred to as a second area. A hollow opening may be formed in the holder 600 in the second area. The second region may be in the shape of a rectangle. The shape of the optical output module 800 may be a rectangular shape. In this case, a part of the effective region from which the image of the optical output module 800 can be output is cut off and may be incident on the lens module 300. More specifically, when the image output from the optical output module 800 passes through the hollow of the second area of the holder 600, the image output from the four parts including the vertex part of the effective area of the rectangular image Some of them may be blocked or blocked. This is because the shape of the hollow of the second region differs from the shape of the optical output module 800. As shown in FIG. 3D, the openings in the second region may have two planes facing each other and two curved surfaces facing each other.

Hereinafter, the configuration of the lens module according to the present embodiment will be described with reference to the drawings.

FIG. 4 is a diagram showing a part of the configuration of a virtual reality display device according to the present embodiment, together with the naked eye of a user.

When the virtual reality display device 10 is worn by the user, the optical output module 800 is positioned on one side of the lens module 300 and the naked eye is located on the other side of the lens module 300. The lens module 300 may include a display side 301 and a visual side 302.

The user &apos; s eyes and the lens module 300 can be spaced apart. At this time, the distance between the naked eye and the lens module 300 can be adjusted. The lens module 300 and the optical output module 800 may be spaced apart from each other. The distance between the lens module 300 and the optical output module 800 may be adjusted. This function is possible because the lens moving unit 400 is movably coupled to the holder 600 through the nascent coupling as described above.

4, the direction of the optical axis of the lens is referred to as the x-axis, and the direction perpendicular to the optical axis is referred to as the y-axis. The direction from the visual side 302 of the lens module 300 to the optical output module 800 The distance d may be smaller than the size (IH, image height) of the optical output module 800 in the y direction. In this case, the optical axis can be referred to as a first axis, and the first axis can be perpendicular to the visual side 302 of the lens module 300.

The size L of the lens module 300 may be equal to or smaller than the size of the light output module 800. [ Here, the size L of the lens module 300 means a diameter when the cross section in the y-axis direction of the lens is circular, and a length of a long side if it is a rectangular shape. The size of the optical output module 800 means the length of one side when the area where the image of the optical output module 800 is outputted is square, and the length of the long side if it is a rectangle.

The pair of lens modules 300 may be provided so that the image output from the optical output module 800 may be focused at different positions, for example, the left eye and the right eye through the respective lens modules 300.

The lens module 300 may be made of a plastic material. However, it is not limited thereto.

The lens module 300 may be provided with at least one lens. Alternatively, the lens module 300 may include a plurality of lenses. The lens module 300 may include at least one Fresnel lens. Here, the Fresnel lens may be a lens divided into several or several circle-shaped lenses in order to reduce the thickness of the lens.

The lens module 300 may include a light output module side 301 and a visual side 302. The optical output module side surface 301 may be closer to the optical output module 800 than the naked eye. The visual side surface 302 may be closer to the naked eye than the optical output module 800. The light output from the optical output module 800 is incident on the optical output module side 301 of the lens module 300 and passes through the lens module 300 to be emitted to the naked eye side 302 and transmitted to the naked eye .

Hereinafter, the configuration of the optical output module according to the present embodiment will be described with reference to the drawings.

5 is a conceptual diagram showing a part of the optical output module according to the present embodiment.

The optical output module 800 may provide an image to the user. The optical output module 800 may provide a virtual reality image to a user of the virtual reality display device 10.

The optical output module 800 may include a light source 810 and a diffraction grating 820. However, at least one of the light source 810 and the diffraction grating 820 in the optical output module 800 may be omitted or changed. The optical output module 800 may further include an image display unit (not shown).

The optical output module 800 may include a plurality of light sources 810 that are spaced apart from each other. The optical output module 800 may include a plurality of light sources 810 spaced apart from each other. The plurality of light sources 810 may be spaced apart from each other. The plurality of light sources 810 may include a red light source, a green light source, and a blue light source. That is, the plurality of light sources 810 may include an RGB light source. The plurality of light sources 810 may include first to third light sources 811, 812, and 813. The plurality of light sources 810 may include first to third light sources 811, 812, and 813 that are spaced apart from each other. The plurality of light sources 810 may include a first light source 811 and a second light source 812 spaced apart from the first light source 811.

The light source 810 may include an exit surface 810a. The distance T from the exit surface 810a of the light source 810 to the ridgeline 830a of the optical path changing unit 830 may be 0.01 to 20 mm.

The optical output module 800 may include a diffraction grating 820 disposed on the output side of the light source 810. The diffraction grating 820 may be disposed above the light source 810. The diffraction grating 820 may be disposed above the light source 810. The diffraction grating 820 may be disposed on the emission side of the light source 810. [ The diffraction grating 820 may be formed to remove the black matrix recognized by the user as the plurality of light sources 810 are spaced apart. That is, the diffraction grating 820 may be formed for depixelization. The diffraction grating 820 may be formed such that the first order diffracted light emitted from the first light source 811 is recognized by the user to be emitted between the first light source 811 and the second light source 812. Thus, the diffraction grating 820 of this embodiment can realize the de-pixelization.

The diffraction grating 820 may include an incident surface 820a through which light emitted from the light source 810 is incident. The diffraction grating 820 may include an exit surface 820b disposed opposite the entrance surface 820a. Light emitted from the light source 810 can be incident through the incident surface 820a. The exit surface 820b may be disposed on the opposite side of the entrance surface 820a.

A plurality of light path changing units 830 having a mountain shape may be disposed on the light exit surface 820b of the diffraction grating 820. [ A plurality of optical path changing units 830 can be disposed on the exit surface 820b of the diffraction grating 820. [ Each of the plurality of light path conversion units 830 may have a mountain shape.

The optical output module 800 according to the present embodiment can satisfy the following expression (1).

[Equation 1]

(? * T) / D <P <(3 *? * T) / D

Where P is the shortest distance between the adjacent ridges 830a of the plurality of optical path changing units 830 and is the wavelength of the light emitted from the light source 810 and T is the distance from the light source 810 to the nearest optical path changing unit 830. [ D is the distance between the light sources 810 of the plurality of light sources 810, and D is the distance between the light sources 810 of the plurality of light sources 810.

At this time,? Can be a green wavelength band. Alternatively, lambda may be an average of the wavelengths of the plurality of light sources 810. Meanwhile, the distance between the light sources 810 may be a distance between the centers of the light sources 810.

Or P is the distance between the ridges 830a of the plurality of optical path changing units 830 and is the wavelength of the light emitted from the light source 810 and T is the distance from the exit surface 810a of the light source 810 To the ridge 830a of the conversion unit 830 and D is the distance between the plurality of light sources 810. [ 5, P, T, and D can be confirmed.

Preferably, the optical output module 800 according to the present embodiment can satisfy the following expression (2).

&Quot; (2) &quot;

P = (2 *? * T) / D

Where P is the distance between the ridges 830a of the plurality of optical path changing units 830 and is the wavelength of the light emitted from the light source 810 and T is the distance from the exit surface 810a of the light source 810 To the ridge 830a of the conversion unit 830 and D is the distance between the plurality of light sources 810. [

Equation (2) may be derived from Equation (3) below.

&Quot; (3) &quot;

P * sin? = M *?

Here,? Is a diffraction angle (radians), m is a diffraction order, P is a distance between ridges 830a of a plurality of optical path changing units 830, Of the light emitted from the light source.

At this time, when θ approaches 0, sin θ approaches tan θ.

That is, Equation (2) can be expressed as P * tan? = M *? When? Approaches zero.

At this time, tan? Is equal to D / 2 divided by T (see Fig. 5).

Therefore, equation (2) can be (P * D) / (2 * T) = m *

At this time, when considering +1-order diffracted light with m = +1, equation (2) can be (P * D) / (2 * T) =

If we sum it up for P, we get P = (2 * l * T) / D.

This process is summarized as Equation 4 below.

&Quot; (4) &quot;

The distance P between the ridges 830a of the plurality of optical path changing units 830 may be proportional to the wavelength lambda of the light emitted from the light source 810. In this embodiment, The distance P between the ridges 830a of the plurality of light path changing units 830 is set to a distance from the exit surface 810a of the light source 810 to the ridgeline 830a of the light path changing unit 830 T). The distance P between the ridges 830a of the plurality of optical path changing units 830 may be inversely proportional to the distance D between the plurality of light sources 810. [

The distance P between the ridges 830a of the plurality of light path changing units 830 is multiplied by the wavelength lambda of the light emitted from the light source 810 to 2, 80% to 120% of the value obtained by dividing the distance D between the plurality of light sources 810 by the distance T from the light source 810a to the ridgeline 830a of the light path conversion unit 830. [

The distance P between the ridges 830a of the plurality of light path changing units 830 is multiplied by the wavelength lambda of the light emitted from the light source 810 to 2, The distance D between the plurality of light sources 810 is multiplied by the distance T from the light source 810a to the ridgeline 830a of the light path conversion unit 830. [

The distance D from the exit surface 810a of the light source 810 to the ridgeline 830a of the optical path changing unit 830 in the case of the distance D between the plurality of light sources 810 is 20 to 50 占 퐉, The value obtained by dividing the distance T by the distance P between the ridges 830a of the plurality of light path changing units 830 may be 16.129 to 55.556.

Substituting D = 0.02 mm and? = 0.00062 mm (wavelength of red light) into the above equation (2), P = 2 * 0.00062 * T / 0.02. In summary, P = 0.062 * T.

Therefore, T / P = 1 / 0.062 = 16.129.

On the other hand, when D = 0.05 mm and? = 0.00045 mm (wavelength of blue light) are substituted into the above equation (2), P = 2 * 0.00045 * T / 0.05. In summary, P = 0.018 * T.

Therefore, T / P = 1 / 0.018 = 55.556.

That is, the minimum value of T / P can be derived when a plurality of light sources 810 emit red light and the distance D between them is 20 μm. The maximum value of T / P can be derived when the distance D between the plurality of light sources 810 and the blue light is 50 m.

The optical output module 800 may include an image display unit that receives light from the light source 810 and converts electrical image information input from the outside into optical image information and outputs the optical image information. The image display unit receives the light from the light source 810 and can convert the electric image information inputted from outside into optical image information and output it. The image display unit can be disposed between the light source 810 and the diffraction grating 820. [

The light source 810 and the diffraction grating 820 may be arranged to be in contact with each other. However, although not shown, the light source 810 and the diffraction grating 820 may be spaced apart from each other. Layers such as a glass, a filter, or a substrate are arranged between the light source 810 and the diffraction grating 820 when the light source 810 and the diffraction grating 820 are disposed apart from each other . At this time, the other layer may include the image display unit described above.

In this embodiment, depixelization can be realized by providing a diffraction grating 820 satisfying the above-described condition between the light source 810 and the naked eye.

6 to 8 are graphs showing the relationship between the distance between the ridges (x-axis) of the plurality of optical path changing units and the distance between the plural light sources (y-axis) in this embodiment. 6 shows a case where the distance from the exit surface of the light source to the ridgeline of the optical path changing unit is 1 mm, Fig. 7 shows the case where the distance from the exit surface of the light source to the ridge of the optical path changing unit is 0.5 mm, Shows a case where the distance from the exit surface of the light source to the ridgeline of the optical path changing unit is 0.25 mm.

The graph of FIG. 6 can be derived by substituting T = 1 mm into Equation 2 (P = (2 *? * T) / D). That is, FIG. 6 is a graph showing the following equation (5).

&Quot; (5) &quot;

D = (2 *?) / P

Here, λ is 0.00045 mm when the light is blue, 0.00052 mm when the light is green, and 0.00062 mm when the light is red.

The graph of FIG. 7 can be derived by substituting T = 0.5 mm into Equation 2 (P = (2 *? * T) / D). That is, FIG. 7 is a graph showing the following equation (6).

&Quot; (6) &quot;

D = lambda / P

Here, λ is 0.00045 mm when the light is blue, 0.00052 mm when the light is green, and 0.00062 mm when the light is red.

The graph of FIG. 8 can be derived by substituting T = 0.25 mm into Equation 2 (P = (2 *? * T) / D). That is, FIG. 8 is a graph showing the following equation (7).

&Quot; (7) &quot;

D = lambda / (2 * P)

Here, λ is 0.00045 mm when the light is blue, 0.00052 mm when the light is green, and 0.00062 mm when the light is red.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. That is, within the scope of the present invention, all of the components may be selectively coupled to one or more of them. Furthermore, the terms "comprises", "comprising", or "having" described above mean that a component can be implanted unless otherwise specifically stated, But should be construed as including other elements. All terms, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Commonly used terms, such as predefined terms, should be interpreted to be consistent with the contextual meanings of the related art, and are not to be construed as ideal or overly formal, unless expressly defined to the contrary.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

800: optical output module 810: light source
820: diffraction grating 830: light path conversion unit

Claims (13)

A plurality of light sources arranged to be spaced apart from each other; And
And a diffraction grating disposed on the upper side of the light source,
Wherein the diffraction grating includes an incident surface through which light emitted from the light source is incident and an exit surface through which light incident on the incident surface is emitted,
A plurality of light path changing units having a mountain shape are formed on an emission surface of the diffraction grating,
An optical output module satisfying the following conditional expression.
<Conditional expression>
(? * T) / D <P <(3 *? * T) / D
Where P is the shortest distance between adjacent ridges of the plurality of optical path changing units, lambda is the wavelength of the light emitted from the light source, T is the distance from the light source to the ridgeline of the optical path changing unit closest to the light source, and D Is a distance between the nearest light sources among the plurality of light sources.
The method according to claim 1,
And the distance from the exit surface of the light source to the ridge of the optical path changing unit is 0.01 to 20 mm.
The method according to claim 1,
Wherein the plurality of light sources comprises a red light source, a green light source, and a blue light source.
The method according to claim 1,
And the light source is disposed apart from the diffraction grating.
The method according to claim 1,
The optical output module provides an image to a user,
Wherein the plurality of light sources include a first light source and a second light source that is spaced apart from the first light source,
Wherein the diffraction grating is formed such that the first-order diffracted light emitted from the first light source is recognized as being emitted by the user between the first and second light sources.
6. The method of claim 5,
Wherein the diffraction grating is configured to remove a black matrix that is recognized by the user as the plurality of light sources are spaced apart.
The method according to claim 1,
Wherein? In the above conditional expression is a green wavelength band.
The method according to claim 1,
Wherein? Of the conditional expression is an average of the wavelengths of the plurality of light sources.
The method according to claim 1,
Wherein the distance between the light sources is a distance between centers of the light sources.
A plurality of light sources arranged to be spaced apart from each other; And
And a diffraction grating disposed on the upper side of the light source,
Wherein the diffraction grating includes an incident surface through which light emitted from the light source is incident and an exit surface through which light incident on the incident surface is emitted,
A plurality of light path changing units having a mountain shape are formed on an emission surface of the diffraction grating,
A value obtained by dividing the distance from the light source to the ridgeline of the light path changing unit closest to the ridgeline by the shortest distance between adjacent ridges of the plurality of light path changing units when the distance between the plurality of light sources is 20 to 50 m is 16.129 55.556 light output module.
holder;
A light output module disposed in the holder and outputting a virtual reality image; And
And a lens module disposed in the holder and spaced apart from the optical output module,
The optical output module includes:
A plurality of light sources arranged to be spaced apart from each other; And
And a diffraction grating disposed on the upper side of the light source,
Wherein the diffraction grating includes an incident surface through which light emitted from the light source is incident and an exit surface through which light incident on the incident surface is emitted,
A plurality of light path changing units having a mountain shape are formed on an emission surface of the diffraction grating,
Wherein the virtual reality display apparatus satisfies the following conditional expression.
<Conditional expression>
(? * T) / D <P <(3 *? * T) / D
Where P is the shortest distance between adjacent ridges of the plurality of optical path changing units, lambda is the wavelength of the light emitted from the light source, T is the distance from the light source to the ridgeline of the optical path changing unit closest to the light source, and D Is a distance between the nearest light sources among the plurality of light sources.
9. The method of claim 8,
And a lens moving unit for movably fixing the lens module to the holder.
10. The method of claim 9,
And the lens moving unit is screwed to the holder.

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