TWI761095B - Head-mounted display device and display system thereof - Google Patents

Abstract

A head-mounted display device and a display system thereof are provided by arranging two light-guiding elements, and optical mirrors capable of reflecting visible light of different wavelengths are respectively arranged in the two light-guiding elements, and a plurality of microstructures with specific angles are arranged between the two light-guiding elements. So that the head-mounted display device can be equipped with 3D display effect at a lower cost.

Description

Head mounted display device and display system thereof

The present invention relates to the field of display systems, in particular, to a display system applied to a head-mounted display device.

Optical technologies related to virtual reality (VR) and augmented reality (AR) have not only attracted global attention in recent years, but also developed at a very fast speed; in addition, they have also been shown in real life. Diverse application potential, such as entertainment, medicine, home furnishing and even military fields, can see products or services achieved by virtual reality and augmented reality technology.

Application examples of virtual reality and augmented reality include various types of display devices, such as a near-eye display device or a head-mounted display (HMD). The so-called near-eye display device is similar in appearance to glasses, and can also be called a glasses-type display, video glasses or a head-mounted display device. It is mainly composed of a carrying part and a display system installed in the carrying part; With good optical effects and the advantages of lightness and lightness, the setting details of the display system have become a very important research and development focus in this field.

For display systems currently common and applied to head-mounted display devices, they can be roughly classified into lens type or optical waveguide type. The lens-type display system essentially involves complex optical system settings, and the technical threshold for production is also relatively high. However, for the optical waveguide type, the concept is to transmit the image/image generated by the display to the human eye through the principle of total reflection of light; the head-mounted display device made based on this characteristic can place the display next to it, Further, the shielding of the system components from external light is greatly reduced, and the display device can be made thinner and lighter.

However, further, when adding a 3D display function to a general optical waveguide head-mounted display device, additional processes or components may be required. Therefore, it is understandable how to design a 3D display device in a simpler and lower cost manner. The optical waveguide type display device with the display effect is a problem that needs to be solved urgently in the related field of the head-mounted display device.

SUMMARY The purpose of providing a simplified abstract of the invention is to provide the reader with a basic understanding of the invention. This summary is not an exhaustive overview of the invention, and it is not intended to identify important or critical elements of the embodiments of the invention or to delineate the scope of the invention.

In view of the content mentioned in the prior art, the inventor of the present invention provides a head-mounted display device and a display system thereof based on years of experience in manufacturing and development of related industries, by arranging two light guide elements, and in the Optical mirrors that can reflect visible light of different wavelengths are respectively arranged in the two light guide elements, and a microstructure with a specific angle is arranged between the two light guide elements, so that a head-mounted display with 3D display effect can be made at a lower cost. device.

Accordingly, in some aspects of the present invention, a display system is provided, which includes a first light guide plate, a second light guide plate, and a display; the first light guide plate has a first surface and an opposite second light guide plate. The surface is further provided with a first optical mirror inside. A third surface of the second light guide plate is connected with the second surface of the first light guide plate by a plurality of microstructures, and a second optical mirror is further arranged inside the second light guide plate. The display is arranged facing the first surface, and a collimating lens group is arranged between the display and the first surface. Wherein, the first optical mirror and the second optical mirror are respectively disposed in the same area corresponding to the first light guide plate and the second light guide plate.

According to some embodiments of the present invention, a first included angle is formed between the first optical mirror and the first surface, and a second included angle is formed between the second optical mirror and the third surface, and the first included angle is equal to the size of the second included angle.

According to some embodiments of the present invention, each of the plurality of microstructures has a micro-reflection surface, and a base angle is defined between the micro-reflection surface and the second surface, and the base angle is different from the first angle or the second angle. Plus no more than 90 degrees.

According to some embodiments of the present invention, the first optical mirror is used to reflect a first light and transmit a second light, and the second optical mirror is used to reflect the second light; wherein, the second light The light has a longer wavelength relative to the first light.

According to some embodiments of the present invention, the first light guide plate, the second light guide plate and the plurality of microstructures are all made of materials with a refractive index of 1.4-1.7.

In some aspects of the present invention, a head-mounted display device is further provided, which includes a head-mounted bearing portion, the head-mounted bearing portion is used for bearing two display systems corresponding to the two eyes of the user and arranged symmetrically, The two display systems both include a light guide component and a display. The light guide assembly includes a front light guide plate disposed close to the human eye and an opposite rear light guide plate, a plurality of microstructures are arranged between the front light guide plate and the rear light guide plate, and the inside of the front light guide plate and the rear light guide plate are respectively arranged There is a front optical mirror and a rear optical mirror, and the front optical mirror and the rear optical mirror are respectively arranged in the same area corresponding to the front light guide plate and the rear light guide plate. The display is arranged corresponding to a surface of the front light guide plate close to the human eye, and a collimating lens group is arranged between the display and the front light guide plate.

According to some embodiments of the present invention, a first included angle is formed between the front optical mirror and a face of the front light guide plate close to the human eye, and a second angle is formed between the rear optical mirror and a face of the rear light guide plate close to the human eye The included angle is equal to the size of the first included angle and the second included angle.

According to some embodiments of the present invention, each of the plurality of microstructures has a micro-reflection surface, and a bottom angle is defined between the micro-reflection surface and a surface of the front light guide plate away from the human eye, the bottom angle and the first included angle or the The sum of the second included angles does not exceed 90 degrees.

According to some embodiments of the present invention, the front optical mirror is used to reflect a first light and transmit a second light, and the rear optical mirror is used to reflect the second light; wherein the second light is opposite to The first light has a longer wavelength.

According to some embodiments of the present invention, the front light guide plate, the rear light guide plate and the plurality of microstructures are all made of materials with a refractive index of 1.4-1.7.

In order to make the description of the present invention more detailed and complete, the following provides illustrative descriptions for the embodiments and specific embodiments of the present invention, but this is not the only form of implementing or using the specific embodiments of the present invention. In this specification and the scope of the appended claims, unless the context dictates otherwise, "a" and "the" may also be construed as plural. In addition, within the scope of this specification and the appended claims, unless otherwise stated, "disposed on something" can be regarded as directly or indirectly in contact with the surface of something by attachment or other forms. The definition of the surface Judgment should be based on the context/paragraph semantics of the description and common knowledge in the field to which this description pertains.

Notwithstanding that the numerical ranges and parameters used to define the invention are approximations, the numerical values set forth in the specific examples have been presented as precisely as possible. Any numerical value, however, inherently contains the standard deviation resulting from individual testing methods. As used herein, "about" generally means within plus or minus 10%, 5%, 1%, or 0.5% of a particular value or range of the actual value. Alternatively, the word "about" means that the actual value lies within an acceptable standard error of the mean, as determined by one of ordinary skill in the art to which this invention pertains. Therefore, unless otherwise stated to the contrary, the numerical parameters disclosed in this specification and the accompanying claims are approximate numerical values and may be changed as required. At a minimum, these numerical parameters should be construed to mean the number of significant digits indicated and the numerical values obtained by applying ordinary rounding.

In order to solve the problems found by the inventors of the present invention on the basis of the prior art, the present invention provides a head-mounted display device and a display system thereof, by arranging two light guide elements, and respectively setting them in the two light guide elements An optical mirror that can reflect visible light of different wavelengths, and a microstructure with a specific angle is arranged between the two light guide elements, thereby making a head-mounted display device with a 3D display effect at a lower cost.

Figures 1 to 2 are all drawn according to an embodiment of the present invention; Figure 1 shows a top cross-sectional view of the display system (in this case, the upper part is defined as the reverse of the direction D3 in the figure), and Figure 2 shows a partial view Displays the top view of the system section. Please refer to Figures 1-2 together. A display system 10 provided by the present invention includes a first light guide plate 100 having a first surface 120 facing a user's human eye 600, a second surface 140 opposite thereto, the third surface 320 and the There is a thickness t between the fourth surfaces 340 . A first optical mirror 150 is further disposed in the first light guide plate 100 , and the first optical mirror 150 is disposed at an angle α with the first surface 120 ; more specifically, the first optical mirror 150 is disposed between the first surface 120 and the second surface 140, and the first optical mirror 150 is disposed between the first surface 120 and the second surface 140 in an unspecified form; for example, it can be inlaid form, or in the form of grooved fastening, or in other conventional forms that can be easily conceived by those skilled in the art to which the present invention pertains.

The display system 10 provided by the present invention further includes a second light guide plate 300 having a third surface 320 facing the second surface 140 and a fourth surface 340 opposite, the third surface 320 and the fourth surface 320 There is a thickness t between the surfaces 340 . A second optical mirror 350 is further provided in the second light guide plate 300 , and the second optical mirror 350 is arranged at an angle α′ with the third surface 320 ; more specifically, the second optical mirror 350 is disposed between the third surface 320 and the fourth surface 340, and the second optical mirror 350 is disposed between the third surface 320 and the fourth surface 340 in an unspecified form; for example, it can be It can be in the form of inlay, or in the form of groove clamping, or in other conventional forms that can be easily conceived by those skilled in the art to which the present invention pertains. In addition, the first optical mirror 150 and the second optical mirror 350 are disposed in the same area corresponding to the first light guide plate 100 and the second light guide plate 300 .

A plurality of microstructures 200 are disposed between the first light guide plate 100 and the second light guide plate 300 ; more specifically, the plurality of microstructures 200 are connected to the second surface 140 and the third surface 320 . Each of the plurality of microstructures 200 further includes a micro-reflection surface 250, each of the plurality of microstructures 200 is in contact with the air through the micro-reflection surface 250, and the inner surface of the micro-reflection surface 250 (ie, the surface that does not contact the air) A bottom angle γ is formed with the second surface 140 .

Please refer to Figures 1 and 2 together. The display system 10 further includes a display 500 and a collimating lens group 700 ; the display 500 is disposed facing the first surface 120 , and the collimating lens group 700 is disposed between the display 500 and the first surface 120 . Further, the display 500 generates a first light beam B1 and a second light beam B2 , which are collimated by the collimating lens group 700 , penetrate the first surface 120 and enter the first light guide plate 100 . Since the first optical mirror 150 can be used to reflect the first light B1 and transmit the second light B2, the second optical mirror 350 can be used to reflect the second light B2. Therefore, the first light B1 is reflected by the first optical mirror 150, and the first total reflection effect is generated on the first surface 120, and the incident angle is β'; and the second light B2 penetrates the After the first optical mirror 150 penetrates the second surface 140 and the third surface 320, and is then reflected by the second optical mirror 350, the first total reflection effect is generated on the third surface 320, and the incident The angle is β; in detail, the wavelength of the second light B2 is greater than the wavelength of the first light B1; and in more detail, the wavelength of the second light B2 is greater than the wavelength of the first light B2; substantially, the The wavelength of the first light B1 is 400-550 nm, and the wavelength of the second light B2 is 550-800 nm. Further, after the first light B1 and the second light B2 are totally reflected in the first light guide plate 100 and the second light guide plate 300 , the micro-reflection surface 250 destroys the first light B1 and the second light The total reflection of B2 and the two are directed to the human eye 600 in a positive and straight line along the direction -D3.

FIG. 3 shows a micro-sectional top view of a display system according to an embodiment of the present invention. Please refer to FIGS. 1 to 3 together, and observe each of the plurality of microstructures 200 at a microscopic level. It can be understood that each of the plurality of microstructures 200 includes a front connecting surface 210 , a side surface 220 , a rear connecting surface 230 and the microstructure. Reflecting surface 250. Wherein, the front connecting surface 210 substantially overlaps with the second surface 140, and the rear connecting surface 230 substantially overlaps the third surface 320; therefore, preferably, the front connecting surface 210 and the draining the micro-reflection surface The 250 series is set in parallel. On the other hand, in order to achieve the above-mentioned optical effects, the internal parameters (angle and length, etc.) of the display system 10 have a certain correlation. Its correlation is based on Snell's Law and Total Internal Reflection. Specifically, the included angle α and the included angle α' have the same magnitude; and the incident angle β and the incident angle β' also have the same magnitude. According to this embodiment, the relationship between the angle α, the incident angle β and the base angle γ is defined as shown in the following equation.

Further, if it is considered that the light generated by the collimating lens group 700 has a half angle of view θ (not shown in the drawings); the half angle of view θ is specifically 0 degrees to 30 degrees, which will further affect the light path, And affect the actual parameters of the included angle α, the incident angle β and the base angle γ. After substantially considering the half angle of view θ, the relationship between the angle α, the incident angle β and the base angle γ is defined as shown in the following equation.

Furthermore, according to the content of this embodiment, the first light guide plate 100 is defined to have a thickness t, and the second light guide plate 300 also has the same thickness t. In addition, the display system 10 does not include the collimating lens group 700 and the part of the display 500 , specifically, the side edges of the first light guide plate 100 , the plurality of microstructures 200 and the second light guide plate 300 The total thickness is a total thickness T. On the other hand, there is a first light-emitting position (not shown in the figure) on the first surface 120, and the distance from the side where the first optical mirror 150 is provided is a first light-emitting distance K; The fourth surface 340 has a second light-emitting position (not shown in the figure), which is a second light-emitting distance L from the side where the second optical mirror 350 is provided. Accordingly, the relationship between the angle α, the incident angle β, the base angle γ, the total thickness T, the thickness t, the first light exit distance K and the second light exit distance L is defined as shown in the following equation .

More specifically, in terms of actual products, the length of the thickness t is 1 mm˜5 mm; preferably, the thickness t is 2.5 mm. The lengths of the sides of the first light guide plate 100 and the second light guide plate 300 are substantially the same; and in detail, the lengths need to be greater than or equal to the first light emitting distance K, so as to achieve the above-mentioned optical effects of the present invention. For each of the plurality of structures 200, the side surface 220 opposite to the micro-reflection surface 250 also substantially contacts the air, and the inner surface of the side surface 220 (ie, the surface that does not contact air) and the third surface 320 (with the The rear connecting surface 230 (overlapping) forms an included angle θ ₁ , and the second surface 140 (and the front connecting surface) forms an included angle θ ₂ . In addition, in addition to the base angle γ, an angle θ ₃ is also formed between the inner surface of the micro-reflection surface 250 (ie, the surface not in contact with the air) and the third surface 320 . Described in more detail, the base angle γ is 55-85 degrees; and the included angle θ ₁ and the included angle θ ₂ are, for example, but not limited to, 90 degrees.

More specifically, in terms of the actual manufacturing process, the plurality of microstructures 200 can be fabricated by etching or laser related fabrication methods. The part of the actual operation process can be on the surface of the first light guide plate 100 or the second light guide plate 300, and then the fabricated light guide plate is laminated with another light guide plate that has not been processed; A distance between the plurality of microstructures 200 is 5-10 microns; in addition, the width of the rear connecting surface 230 is shorter than the width of the front connecting surface 210, and the width of the rear connecting surface 230 is substantially the same as the length of the side surface 220 The same, all are about 5~30 microns. On the other hand, in this embodiment, the first light guide plate 100 , the second light guide plate 300 and the plurality of microstructures 200 are made of materials with the same refractive index, and the refractive index is about 1.45-1.70 However, the essential components of its materials are not limited in this case, so it can be made of different components or integrally formed with the same components. In addition, the first optical mirror 150 can reflect the first light B1 and transmit the second light B2 through the coated optical film; and the second optical mirror 350 can also pass through the coated optical film. The effect of reflecting the second light B2 is achieved.

Figures 4 to 5 are shown according to an embodiment of the present invention; Figure 4 is a cross-sectional top view of the second display system, and Figure 5 is a head-mounted display device using the second display system of Figure 4 Schematic. Please refer to Figures 1 to 5 together. The present invention provides a head-mounted display device 30, which includes a head-mounted support portion 800 for erecting on the head of a human body, and the head-mounted support portion 800 is used for supporting the user's human eyes 600 and 600' respectively. , and a first display system 10 and a second display system 20 are symmetrically arranged. Specifically, the head-mounted support portion 800 may be glasses, eye masks, helmets, or other forms that can be conceived by those with ordinary knowledge in the technical field to which the present application pertains.

Further, the technical content of the first display system 10 has been presented as the display system of the above-mentioned embodiment; and the second display system 20 is symmetrically arranged with the first display system 10 . It can be understood from this that the first display system 10 and the second display system 20 have the same components and parameter settings. Specifically, the second display system 20 includes a first light guide plate 100' and the second light guide plate 300', and in the head-mounted display device 30 provided in this embodiment, the first light guide plate (100 and 100') and the second light guide plate (300 and 300') have a positional correspondence between front and rear; in this embodiment, the direction -D2 is defined as the front. Further, the second display system 20 also includes the first optical mirror 150 ′, the second optical mirror 350 ′, the plurality of microstructures 200 ′, etc. The definition of the parameters is also the same as that of the first display system 10 , so in the This will not be repeated.

According to the content of the above-mentioned embodiments, it can be understood that the implementation of the present invention can be relatively simple and inexpensive to make a single display system produce 3D visual effects by dislocation of different wavelengths; and two symmetrical display systems can be used. By providing different proportions of color, the image dislocation is further enhanced to provide a realistic 3D effect.

Although the present invention has been disclosed above with embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the art may make minor changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be based on the scope defined by the appended patent application.

10: Display system (first display system) 20: Second display system 30: Head mounted display device 100, 100': First light guide plate 120: First surface 140: Second surface 150, 150': First optical mirror 200, 200': Microstructure 210: Front connecting surface 220: Side surface 230: Rear connecting surface 250, 250': Micro-reflecting surface 300, 300': Second light guide plate 320: Third surface 340: Fourth surface 500, 500': Display 600, 600': Human eye 700, 700': Collimating lens group 800: head-mounted bearing part B1: first light B2: second light T: total thickness t: thickness K: first light exit distance L: second light exit distance α, α': angle β, β' : Incident angle γ, γ': Base angle θ ₁ ~θ ₃ : Included angle D1~D3: Direction

In order to make the above-mentioned and other objects, features, advantages and embodiments of the present invention more easily understood, the descriptions of the accompanying drawings are as follows: FIG. 1 is a cross-sectional top view of a display system according to an embodiment of the present invention; FIG. 2 is a cross-sectional top view of a partial display system according to an embodiment of the present invention; FIG. 3 is a top view of a micro-section of a display system according to an embodiment of the present invention; FIG. 4 is a cross-sectional top view of two display systems according to an embodiment of the present invention; FIG. 5 is a schematic diagram of a head-mounted display device using a second display system according to an embodiment of the present invention.

In accordance with common practice, the various features and elements in the drawings are not drawn to scale, but are drawn in order to best represent specific features and elements relevant to the present invention. Furthermore, the same or similar reference numerals are used to refer to similar elements and parts among the different figures.

10: Display system (first display system)

20: Second Display System

100,100': The first light guide plate

150, 150': first optics

200,200': Microstructure

250,250': Micro-reflective surface

300,300': Second light guide plate

500,500’: Display

600,600': human eye

700,700': collimating lens group

α,α': angle

β,β': Incident angle

D1~D3: Direction

Claims (10)

A display system, comprising: a first light guide plate with a first surface and a second surface opposite, a first optical mirror is further arranged in the first light guide plate; a second light guide plate with a The third surface and the second surface of the first light guide plate are connected by a plurality of microstructures, and the second light guide plate is further provided with a second optical mirror; and a display is disposed facing the first surface, and the display A collimating lens group is arranged between the first surface and the first surface; wherein, the first optical mirror and the second optical mirror are respectively arranged in the same area corresponding to the first light guide plate and the second light guide plate; wherein, The microstructure has a side surface, a front connection surface, a rear connection surface, and a micro-reflection surface; wherein the width of the rear connection surface of the microstructure is shorter than the width of the front connection surface, and the rear connection surface is the same as the width of the front connection surface. The lengths of the side surfaces are the same, ranging from 5 to 30 micrometers; the distance between the adjacent microstructures is 5 to 10 micrometers. The display system of claim 1, wherein a first angle is formed between the first optical mirror and the first surface, a second angle is formed between the second optical mirror and the third surface, and the The first included angle and the second included angle are equal in size. The display system of claim 2, wherein each of the plurality of microstructures has a micro-reflection surface, a bottom angle is defined between the micro-reflection surface and the second surface, the bottom angle and the first included angle or the first angle The two included angles add up to no more than 90 degrees. The display system of claim 3, wherein the first optical mirror is used to reflect a first light and transmit a second light, and the second optical mirror is used to reflect the second light; wherein, The second light has a longer wavelength relative to the first light. The display system of claim 3, wherein the first light guide plate, the second light guide plate and the plurality of microstructures are all made of materials with a refractive index of 1.4-1.7. A head-mounted display device, which includes a head-mounted bearing part, the head-mounted bearing part is used to carry two display systems corresponding to the two eyes of a user and arranged symmetrically, the two display systems both include: a light guide component , which includes a front light guide plate arranged close to the human eye and a rear light guide plate opposite, a plurality of microstructures are arranged between the front light guide plate and the rear light guide plate, and a front light guide plate and a rear light guide plate are respectively arranged inside the front light guide plate and the rear light guide plate. Optical mirror and a rear optical mirror, and the front optical mirror and the rear optical mirror are respectively arranged in the same area corresponding to the front light guide plate and the rear light guide plate; and a display, which corresponds to a face of the front light guide plate close to the human eye A collimating lens group is arranged between the display and the front light guide plate; wherein, the microstructure has a side surface, a front connecting surface, a rear connecting surface, and a micro-reflection surface; wherein the microstructure has the The width of the rear connecting surface is shorter than the width of the front connecting surface, and the lengths of the rear connecting surface and the side surface are the same, ranging from 5 to 30 micrometers; the distance between the adjacent microstructures is 5 to 10 micrometers. The head-mounted display device as claimed in claim 6, wherein a first included angle is formed between the front optical mirror and a face of the front light guide plate close to the human eye, and the rear optical mirror and a face of the rear light guide plate close to the human eye A second included angle is formed between them, and the first included angle and the second included angle are equal in size. The head-mounted display device as claimed in claim 7, wherein each of the plurality of microstructures has a micro-reflection surface, and a bottom angle is defined between the micro-reflection surface and a surface of the front light guide plate away from the human eye, and the bottom angle and The sum of the first included angle or the second included angle does not exceed 90 degrees. The head-mounted display device of claim 8, wherein the front optical mirror is used for reflecting a first light ray and penetrating a second light ray, and the rear optical mirror is used for reflecting the second light ray; wherein , the second light has a longer wavelength relative to the first light. The head-mounted display device of claim 8, wherein the front light guide plate, the rear light guide plate and the plurality of microstructures are all made of materials with a refractive index of 1.4-1.7.

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