CN215986726U

CN215986726U - Augmented reality display system

Info

Publication number: CN215986726U
Application number: CN202122210692.0U
Authority: CN
Inventors: 舒新炜; 董若
Original assignee: Jitong Technology Beijing Co ltd
Current assignee: Jitong Technology Beijing Co ltd
Priority date: 2021-09-13
Filing date: 2021-09-13
Publication date: 2022-03-08
Anticipated expiration: 2031-09-13

Abstract

The embodiment of the utility model discloses an augmented reality display system, which comprises a light splitting unit, a curved surface reflecting unit, a lens group and a display, wherein the light splitting unit is used for splitting a light beam; the lens group comprises a plurality of lenses, the focal length F1 of the lens group is adjusted to meet the condition that | F1| is less than or equal to 35mm which is more than or equal to 10mm, and a first display light beam emitted by the lens group focusing display forms a first focusing light beam; the light splitting unit splits the first focused light beam to form a first split light beam and a second split light beam; the first split light beam is transmitted from the light splitting unit, the second split light beam is reflected by the light splitting unit, and the curved surface reflecting unit converges and reflects the second split light beam to form a reflected light beam; the light splitting unit also adjusts the reflected light beam to form linearly polarized light which enters the eyes of the user to form a virtual image; the natural light sequentially enters the eyes of the user through the curved surface reflection unit and the light splitting unit to form a real object image. The technical problem that the existing enhanced display device is poor in visual imaging caused by small field of view, short exit pupil distance, small exit pupil diameter and short focal length is solved.

Description

Augmented reality display system

Technical Field

The embodiment of the utility model relates to the technical field of augmented display, in particular to an augmented reality display system.

Background

In recent years, Augmented Reality (AR) display devices have been rapidly developed, and since the system is a head-mounted system, it must be compact and lightweight to enhance user comfort. For an augmented reality display device, a large field of view is very important, which can increase the sense of immersion of a user, enabling an observer to observe a high-quality moving image to the maximum extent. Compact and lightweight structure can be very big reinforcing wearer's comfort, and suitable exit pupil distance can make the observer wear other visual system (like myopia glasses) and use, has increased the application scope of system to the wearer. However, structural parameters of the optical system, such as the field of view, the exit pupil distance, the large exit pupil diameter, and the short focal length, are restricted from each other, and it is considerably difficult to satisfy the above conditions.

The existing enhanced display device has the problems of small view field, short exit pupil distance, small exit pupil diameter, short focal length, unclear imaging and the like, the imaging performance of combining a real object and a virtual object of the enhanced display device is influenced, and the user experience is poor.

SUMMERY OF THE UTILITY MODEL

The embodiment of the utility model provides an augmented reality display system, which aims to solve the technical problems of small view field, short exit pupil distance, small exit pupil diameter and short focal length on the basis of compactness and light weight of an augmented display device.

In a first aspect, an embodiment of the present invention provides an augmented reality display system, including a light splitting unit, a curved surface reflection unit, a lens group, and a display;

the display is used for emitting a first display light beam;

the lens group comprises a plurality of lenses, and the plurality of lenses comprise a negative focal length lens and a positive focal length lens; the combined focal length of the lens group is F1, and | F1| is more than or equal to 10mm and less than or equal to 35 mm; the lens group is positioned on the propagation path of the first display beam and is used for focusing the first display beam to form a first focusing beam;

the light splitting unit is positioned on a propagation path of the first focusing light beam and is used for splitting the first focusing light beam to form a first light splitting light beam and a second light splitting light beam; the first split light beam is transmitted from the light splitting unit, and the second split light beam is reflected by the light splitting unit;

the curved surface reflection unit is positioned on the propagation path of the second split light beam and is used for converging and reflecting the second split light beam to form a reflected light beam; the light splitting unit is also positioned on the path of the reflected light beam and is used for adjusting the reflected light beam to form linearly polarized light and then enter the eyes of a user to form a virtual image;

and natural light sequentially passes through the curved surface reflection unit and the light splitting unit and enters eyes of a user to form a real object image.

Optionally, the lens group further comprises a mirror;

the reflector is used for changing the propagation direction of the first display light beam.

Optionally, the light splitting unit includes a quarter-wave plate, a polarization reflection film layer, and a light splitting mirror body, where the light splitting mirror body includes a first light splitting surface and a second light splitting surface;

the polarization reflection film layer is positioned on one side of the first light splitting surface, and the quarter-wave plate is positioned on one side, far away from the first light splitting surface, of the polarization reflection film layer; the second light dividing surface is plated with an antireflection film; or, the first light-dividing surface is plated with an antireflection film; the quarter-wave plate is located on one side of the second light splitting surface, and the polarization reflection film layer is located on one side, far away from the second light splitting surface, of the quarter-wave plate.

Optionally, an included angle between the optical axis direction of the polarization reflection film and the optical axis direction of the quarter-wave plate is 45 ° or 135 °.

Optionally, the curved surface reflection unit includes a first curved surface and a second curved surface;

the first curved surface is plated with an antireflection film, and the second curved surface is plated with a light splitting film;

or, the first curved surface is plated with a light splitting film, and the second curved surface is plated with an antireflection film.

Optionally, an included angle between the tangent plane of the center of the curved surface reflection unit and the plane where the light splitting unit is located is α, and α is greater than or equal to 30 ° and less than or equal to 60 °.

Optionally, the focal distance of the curved surface reflection unit with respect to the reflected light beam is F2,

20mm≤|F2|≤35mm；

the focal length of the curved surface reflection unit relative to the natural light is F3, | F3| ≧ 500 mm.

Optionally, the thickness of the curved surface reflection unit is H1, and H1 is greater than or equal to 1mm and less than or equal to 5 mm.

Optionally, the thickness of the light splitting unit is H2, and H2 is not less than 0.3mm and not more than 2 mm.

Optionally, the first display beam includes at least one of natural light, linearly polarized light, and elliptically polarized light.

The embodiment of the utility model provides an augmented reality display system, through reasonable setting system including beam splitting unit, curved surface reflection unit, battery of lens and display, set up battery of lens and include a plurality of lenses, include negative focal length lens and positive focal length lens among the plurality of lenses, the focus F1 of adjusting the battery of lens satisfies ≤ 10 | F1| ≦ 35mm, can effectively reduce the focus of system, under the condition that satisfies the visual imaging effect of system, improve the system compactness; the lens group focuses a first display beam emitted by the display to form a first focused beam; the light splitting unit splits the first focused light beam to form a first split light beam and a second split light beam; the first split light beam is transmitted from the light splitting unit, the second split light beam is reflected by the light splitting unit, and the curved surface reflecting unit converges in parallel and reflects the second split light beam to form a reflected light beam; the light splitting unit further adjusts the reflected light beam to form linearly polarized light, and then the linearly polarized light enters the eyes of a user to form a virtual image, so that the visual imaging effect is improved; the augmented reality display system provided by the utility model has the advantages that the focal length is short, the structure is compact, the virtual image and the real object image can be superposed to achieve the effect of augmented reality, and the visual experience of a user is improved.

Drawings

Fig. 1 is a schematic structural diagram of an augmented reality display system according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of another augmented reality display system according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a light splitting unit according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of another light splitting unit according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the utility model and are not limiting of the utility model. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

Fig. 1 is a schematic structural diagram of an augmented reality display system according to an embodiment of the present invention. As shown in fig. 1, the augmented reality display system includes a light splitting unit 1, a curved surface reflecting unit 2, a lens group 3, and a display 4; the display 4 is used for emitting a first display light beam; the lens group 3 includes a plurality of lenses including a negative focal length lens and a positive focal length lens; the combined focal length of the lens group 3 is F1, and | F1| is more than or equal to 10mm and less than or equal to 35 mm; the lens group 3 is positioned on the propagation path of the first display beam A and is used for focusing the first display beam A to form a first focusing beam B; the light splitting unit 1 is positioned on the propagation path of the first focused light beam B and is used for splitting the first focused light beam B into a first split light beam B1 and a second split light beam B2; the first split light beam B1 is transmitted from the light splitting unit 1, and the second split light beam B2 is reflected by the light splitting unit 1; the curved surface reflection unit 2 is positioned on the propagation path of the second split light beam B2 and is used for converging and reflecting the second split light beam B2 to form a reflected light beam; the light splitting unit 2 is also positioned on the path of the reflected light beam and is used for adjusting the reflected light beam to form linearly polarized light and then enter the eyes of a user to form a virtual image; the natural light C enters the eyes of the user to form a real image through the curved surface reflection unit 2 and the light splitting unit 1 in sequence.

Illustratively, as shown in fig. 1, the augmented reality display system includes a light splitting unit 1, a curved reflecting unit 2, a lens group 3, and a display 4. The display 4 emits a first display beam a for virtual imaging of the user's eye. For example, the Display 4 may be a Liquid Crystal on Silicon (LCoS), an Organic Light-Emitting Diode (OLED), a Digital Light Processing (DLP), a Liquid Crystal panel (LCD), or the like, and has a size of 0.1 inch to 2 inches and a resolution greater than 720P. The lens group 3 is arranged to comprise a plurality of lenses, the first display light beam A is focused to form a first focused light beam B, the plurality of lenses at least comprise a negative focal length lens and a positive focal length lens, so that the combined focal length of the lens group 3 is F1 and the integral of F1 is more than or equal to 10mm and less than or equal to 35mm, and the first display light beam A is converged by controlling the combined focal length F1 of the lens group 3, so that the energy utilization rate of light is improved; on the other hand, the lens group 3, the light splitting unit 1 and the curved surface reflection unit 2 are combined to effectively increase the field of view, the exit pupil distance, the exit pupil diameter, the focal length and the like of the control system, wherein the field of view of the system can be greater than or equal to 60 degrees through practical tests, the exit pupil distance can be greater than or equal to 18mm, the exit pupil diameter can be greater than or equal to 6mm, and compared with the existing products, the imaging effect is more excellent due to the more compact system structure.

Specifically, the light splitting unit 1 includes a light splitter, and splits the first focused light beam B. The first focused light beam focused by the lens group 3 reaches the light splitting unit 1, and the light splitting unit 1 splits the first focused light beam B into a first split light beam B1 and a second split light beam B2 with different polarization directions, for example, the first split light beam B1 may be P-polarized light, and the second split light beam B2 may be S-polarized light. In which the polarization direction, i.e. the direction in which the vibration direction does not coincide with the propagation direction, when light rays penetrate the surface of an optical element, such as a beam splitter, at non-perpendicular angles, both the reflection and transmission characteristics depend on polarization phenomena, in which case the coordinate system used is defined by the plane containing the input and reflected light beams, and if the polarization vector of the light rays is in this plane, it is called P-polarization, and if the polarization vector is perpendicular to this plane, it is called S-polarization, and the polarization directions of the P-polarization and S-polarization are perpendicular to each other, and any input polarization state can be represented as the vector sum of the S and P components. The light-splitting unit 1 is set such that the first split light beam B1 is transmitted from the light-splitting unit 1, and the second split light beam B2 is reflected by the light-splitting unit 1, i.e., P-polarized light is transmitted and S-polarized light is reflected. The curved surface reflection unit 2 is arranged on the propagation path of the second split light beam B2, and the curved surface reflection unit 2 can adopt a spherical concave mirror, so as to improve the capability of converging light beams. When the second split light beam B2 reaches the curved surface reflection unit 2, the reflection unit 2 serves to condense and reflect the second split light beam B2 in parallel on the one hand, and to transmit natural light on the other hand. When the second split light beam B2 is converged in parallel and reflected to form a reflected light beam, the curved surface reflection unit 2 changes the propagation direction and the distribution direction of the second split light beam B2, and when the reflected light beam reaches the light splitting unit 1, the reflected light beam is adjusted to form linearly polarized light and then enters eyes of a user to form a virtual image, wherein in the propagation direction of the light, the light vector vibrates only along a fixed direction, the light is called plane polarized light, and because the track of the end point of the light vector is a straight line and is also called linearly polarized light, the linearly polarized light can effectively improve the visual imaging effect of the virtual image; meanwhile, natural light C enters eyes of a user to form a real object image through the curved surface reflection unit 2 and the light splitting unit 1 in sequence, and the virtual image and the real object image are superposed to achieve the effect of augmented reality.

To sum up, the augmented reality display system provided by the embodiment of the present invention reasonably sets the light splitting unit, the curved surface reflection unit, the lens group and the display of the system, the lens group is set to include a plurality of lenses, the plurality of lenses include a negative focal length lens and a positive focal length lens, the focal length F1 of the lens group is adjusted to satisfy that | F1| is not less than 10mm and not more than 35mm, the focal length of the system can be effectively reduced, and the compactness of the system is improved under the condition of satisfying the visual imaging effect of the system; the lens group focuses a first display beam emitted by the display to form a first focused beam; the light splitting unit splits the first focused light beam to form a first split light beam and a second split light beam; the first split light beam is transmitted from the light splitting unit, the second split light beam is reflected by the light splitting unit, and the curved surface reflecting unit converges in parallel and reflects the second split light beam to form a reflected light beam; the light splitting unit also adjusts the reflected light beam to form linearly polarized light which enters the eyes of a user to form a virtual image, and the linearly polarized light can effectively improve the visual imaging effect of the virtual image; the augmented reality display system provided by the utility model has the advantages that the focal length is short, the structure is compact, the virtual image and the real object image can be superposed to achieve the effect of augmented reality, and the visual experience of a user is improved.

Fig. 2 is a schematic structural diagram of another augmented reality display system according to an embodiment of the present invention. As shown in fig. 2, optionally, the lens group 3 further includes a mirror 31; the mirror 31 is used to change the propagation direction of the first display beam.

Illustratively, as shown in fig. 2, at least one mirror 31 is included in the lens group 3, and the propagation direction of the first display light beam emitted from the display 4 is changed by adjusting the number and the position of the mirrors 31, and the positions of the lens 3 and the display 4 are changed, so that the volume of the system can be reduced, and the whole system is compact.

Optionally, the first display beam includes at least one of natural light, linearly polarized light, and elliptically polarized light. The natural light is also called as natural light, does not directly display the polarization phenomenon, comprises all possible vibration directions perpendicular to the propagation direction of the light wave, so the natural light does not display the polarization, the natural light directly emitted from a common light source is a random set of innumerable polarized light, so the direction of the light intensity deviating from the direction cannot be found when the natural light is directly observed, the light with the same light wave intensity vibrating along all the directions is called as natural light, and the light is also called as visible light. In the propagation direction of light, the light vector vibrates only in a fixed direction, and the light is called plane polarized light, and the track of the end point of the light vector is a straight line and is also called linearly polarized light. Circularly polarized light is a locus traced by the end of an electric field or an optical vector of light on a plane perpendicular to a propagation direction, and when two mutually perpendicular vibrations act on a point at the same time, if the frequencies of the two vibrations are the same and a fixed phase difference exists, the locus of the resultant vibration of the point is generally elliptical, that is, elliptically polarized light is formed. By setting the display 4, different displays 4 can be selected so that at least one of the emitted natural light, linearly polarized light and elliptically polarized light is finally incident to the eyes of the user in the form of linearly polarized light to form a virtual image.

Fig. 3 is a schematic structural diagram of a light splitting unit according to an embodiment of the present invention; fig. 4 is a schematic structural diagram of another light splitting unit according to an embodiment of the present invention. As shown in fig. 3 and 4, the spectroscopic unit 1 optionally includes a quarter-wave plate 11, a polarization reflection film layer 12, and a spectroscopic main body 13. The spectroscope body 13 includes a first light dividing surface 131 and a second light dividing surface 132; the polarization reflection film layer 12 is located on one side of the first light splitting surface 131, and the quarter-wave plate 11 is located on one side of the polarization reflection film layer 12 away from the first light splitting surface 131; the second light splitting surface 131 is plated with an antireflection film; or, the first light-dividing surface 131 is plated with an antireflection film; the quarter-wave plate 11 is located on one side of the second light splitting surface 132, and the polarization reflection film layer 12 is located on one side of the quarter-wave plate 11 away from the second light splitting surface 132.

Illustratively, as shown in fig. 1, 2 and 3, the light splitting unit 1 includes a light splitting body 13, and the light splitting body 13 includes a first light splitting surface 131 and a second light splitting surface 132. As shown in fig. 2, along the incident direction of the first focused light beam B, the polarization reflection film layer 12 is attached to one side of the first light splitting surface 131, the quarter-wave plate 11 is attached to one side of the polarization reflection film layer 12 away from the first light splitting surface 131, and the second light splitting surface 131 is coated with an antireflection film. The quarter-wave plate is also called as a quarter-wave retardation plate, when light with a certain wavelength vertically enters and passes through, the phase difference between emergent ordinary light and emergent extraordinary light is 1/4 wavelength, and the quarter-wave plate is usually used for changing linearly polarized light into circularly polarized light or elliptically polarized light in an optical path; or vice versa; when the same light beam passes through the quarter-wave plate twice, the phase difference between the emergent ordinary light and the emergent extraordinary light is 1/2 wavelengths, namely the polarization direction is deflected by 90 degrees. The polarization reflection film layer 12 enables a first split light beam B1 with the polarization direction parallel to the optical axis direction of the polarization reflection film layer 12 to transmit, a second split light beam B with the polarization direction not parallel to the optical axis direction of the polarization reflection film layer 12 is reflected, the light splitting unit 1 completes light splitting after the quarter-wave plate 11 and the polarization reflection film layer 12 act together on the first focused light beam B, meanwhile, the transmittance of transmitted light is increased through the antireflection film, and the energy utilization rate of light is improved.

Specifically, taking fig. 2 as an example, when the first focused light beam leaving the lens group 3 is natural light, the light still passes through the quarter-wave plate 11 and reaches the surface of the polarization reflection film 12. For example, the film layer properties of the polarization reflection film 12 are set to P-polarized light reflection and S-polarized light transmission, that is, P-polarized light in the natural light vector is reflected by the polarization reflection film 12, and S-polarized light in the natural light vector is transmitted through the polarization reflection film 12 to become stray light. The reflected P-polarized light passes through the quarter-wave plate 11 again, generates 1/4 wavelength delay in phase and is split into elliptical polarized light; the elliptically polarized light reaches the reflection unit 2, is converged and reflected, then passes through the quarter-wave plate 11 of the light splitting unit 1 again, and the phase of the elliptically polarized light is subjected to 1/4 wavelength delay so as to be adjusted to be S-polarized light, so that the film property that the polarization reflection film 12 transmits the S-polarized light is met; the adjusted S-polarized light enters the eyes of the user to form a virtual image, the linearly polarized light can effectively improve the visual imaging effect of the virtual image, and the virtual image and the real image seen by the eyes of the user are overlapped to achieve the effect of augmented reality.

Alternatively, taking fig. 2 as an example, when the first focused light beam leaving the lens group 3 is elliptically polarized light, the light beam is split into linearly polarized P-polarized light (or S-polarized light) with a wavelength delay of 1/4 after passing through the quarter-wave plate 11, and reaches the surface of the polarization reflection film 12, for example, the film properties of the polarization reflection film 12 are set as P-polarized light reflection and S-polarized light transmission. The P-polarized light is reflected by the polarization reflection film 12, and the S-polarized light is transmitted by the polarization reflection film 12 to become stray light; the reflected P-polarized light passes through the quarter-wave plate 11 again to generate 1/4 wavelength delay and is split into elliptical polarized light, the elliptical polarized light reaches the reflection unit 2, is converged and reflected, then passes through the quarter-wave plate 11 of the light splitting unit 1 again, and at the moment, the phase of the elliptical polarized light is 1/4 wavelength delay and is adjusted to be S-polarized light, so that the film property that the polarization reflection film 12 transmits the S-polarized light is met. The adjusted S-polarized light enters the eyes of the user to form a virtual image, the linearly polarized light can effectively improve the visual imaging effect of the virtual image, and the virtual image and the real image seen by the eyes of the user are overlapped to achieve the effect of augmented reality.

Still alternatively, taking fig. 2 as an example, when the first focused beam light leaving the lens assembly 3 is linearly polarized S-polarized light (or P-polarized light), the light passes through the quarter-wave plate 11 and then is split into elliptically polarized light with 1/4 wavelength delay. Since any one of the input polarization states can be expressed as a vector sum of S and P components, elliptically polarized light reaches the surface of the polarization reflection film 12, and for example, the film properties of the polarization reflection film 12 are set to P-polarized light reflection and S-polarized light transmission. The P-polarized light in the elliptical polarized light vector is reflected by the polarization reflection film 12, and the S-polarized light in the elliptical polarized light vector is transmitted through the polarization reflection film 12 to become stray light. The reflected P-polarized light passes through the quarter-wave plate 11 again, generates 1/4 wavelength delay in phase and is split into elliptical polarized light; the elliptically polarized light reaches the reflection unit 2, is converged and reflected, then passes through the quarter-wave plate 11 of the light splitting unit 1 again, and the phase of the elliptically polarized light is subjected to 1/4 wavelength delay so as to be adjusted to be S-polarized light, so that the film property that the polarization reflection film 12 transmits the S-polarized light is met. The adjusted S-polarized light enters the eyes of the user to form a virtual image, the linearly polarized light can effectively improve the visual imaging effect of the virtual image, and the virtual image and the real image seen by the eyes of the user are overlapped to achieve the effect of augmented reality.

The film properties of the polarization reflection film 12 can also be set to S-polarized light reflection and P-polarized light transmission, and the principle is the same as the above embodiments, which is not illustrated here.

It should be understood that, when the light of the first focused light beam is natural light and linearly polarized light, the energy utilization rate of the first focused light beam is only 50% of the energy utilization rate of the elliptically polarized light, and the visual imaging effect of the augmented reality system can also be improved by reasonably selecting the display.

Fig. 3 is another possible structure of the light splitting unit 1, in which a quarter-wave plate 11 is attached to one side of the second light splitting surface 132, a polarization reflection film 12 is attached to one side of the quarter-wave plate 11 away from the second light splitting surface 132, and an antireflection film is coated on the first light splitting surface 131, and the effective effect of the light splitting unit 1 shown in fig. 3 is the same as that of fig. 2, and details thereof are omitted. It should be noted that fig. 2 and 3 only show two possible embodiments, and it is sufficient to ensure that the first focused light beam B focused by the lens group 3 reaches the quarter-wave plate 11 first.

On the basis of the above embodiment, optionally, the angle between the optical axis direction of the polarization reflection film and the optical axis direction of the quarter-wave plate is 45 ° or 135 °.

Exemplarily, the included angle between the optical axis direction of the polarization reflection film and the optical axis direction of the quarter-wave plate is set to be 45 degrees or 135 degrees, so that the splitting ratio of the polarization reflection film to the P-polarized light and the S-polarized light meets 1:1, and when the P-polarized light reflects the S-polarized light and transmits the S-polarized light (or when the S-polarized light reflects the P-polarized light and transmits the P-polarized light), the energy utilization rate of the incident light is improved as much as possible, and the visual effect of the virtual image entering the eye is improved.

Optionally, when the first focused light beam leaving the lens group 3 is linearly polarized light S-polarized light (or P-polarized light), an included angle between the polarization direction of the linearly polarized light and the optical axis direction of the quarter-wave plate is required to be 45 ° or 135 °, further meeting the requirement that the splitting ratio of the polarization reflective film to the P-polarized light and the S-polarized light reaches 1:1, improving the energy utilization rate of incident light, and improving the visual effect of the virtual image entering the eye.

On the basis of the above embodiment, with continued reference to fig. 1, the curved surface reflection unit 2 includes a first curved surface 21 and a second curved surface 22; the first curved surface 21 is plated with an antireflection film, and the second curved surface 22 is plated with a light splitting film; or, the first curved surface 21 is plated with a light splitting film, and the second curved surface 22 is plated with an antireflection film.

For example, as shown in fig. 1, when the first curved surface 21 of the curved surface reflection unit 2 is coated with an antireflection film and the second curved surface 22 is coated with a spectroscopic film, optionally, the first curved surface 21 and the second curved surface 22 have the same surface type. The second split light beam B2 split by the light splitting unit 1 passes through the antireflection film of the first curved surface 21 and is reflected by the light splitting film of the second curved surface 22 to be a reflected light beam emitted in parallel; the energy utilization rate of light can be improved and the light loss can be reduced by additionally plating the antireflection film. Optionally, the transmittance inverse ratio of the transmitted light to the reflected light of the light splitting film is 1:1, and by the arrangement, the light utilization rate of natural light and reflected light beams can be effectively balanced, and the superimposed visual imaging effect of virtual images and real images of eyes is improved.

Or, the first curved surface 21 of the curved surface reflection unit 2 is plated with a spectroscopic film, and the second curved surface 22 is plated with an antireflection film, so that a part of the second split light beam B2 split by the light splitting unit 1 is reflected by the spectroscopic film of the first curved surface 21 into a reflected light beam which is emitted in parallel, and a part of the second split light beam B2 passes through the antireflection film of the second curved surface 22 and becomes stray light; the transmittance of stray light can be improved, energy accumulation can be reduced, the incidence rate of natural light can be improved, and the light loss of the natural light can be reduced by additionally plating an anti-reflection film. The achieved effect is the same as the above embodiment, and is not described herein again.

Optionally, an included angle between the tangent plane of the center of the curved surface reflection unit and the plane where the light splitting unit is located is α, and α is greater than or equal to 30 degrees and less than or equal to 60 degrees.

Exemplarily, as shown in fig. 1, an included angle α between a tangent plane at the center of the curved surface reflection unit 2 and a plane where the light splitting unit 1 is located satisfies an angle α of 30 ° or more and 60 ° or less, and by adjusting the included angle α, the distance between the curved surface reflection unit 2 and the light splitting unit 1 is adjustable, and the angle and the direction of the reflected light beam are adjustable, so that the included angle α directly affects parameters of the field of view, the diameter of the exit pupil, and the like of the system, and the field of view, the diameter of the exit pupil, and the like of the system can be effectively improved by reasonably setting the included angle α.

On the basis of the above embodiment, optionally, the focal distance of the curved surface reflection unit relative to the reflected light beam is F2, and | F2| is more than or equal to 20mm and less than or equal to 35 mm; the focal distance of the curved surface reflection unit relative to natural light is F3, | F3| ≧ 500 mm.

Illustratively, the focal length F2 of the curved surface reflection unit relative to the reflected light beam is more than or equal to 20 and less than or equal to | F2| and less than or equal to 35mm, and the focal length F3 of the curved surface reflection unit relative to the incident light of natural light is more than or equal to | F3| > or equal to 500mm, so that the exit pupil distance, the focal length and the like of the system can be improved, and the overlapping visual imaging effect of the virtual image and the real image of the eye can be improved.

Optionally, the thickness of the curved surface reflection unit is H1, H1 is greater than or equal to 1mm and less than or equal to 5mm, the thickness of the light splitting unit is H2, and H2 is greater than or equal to 0.3mm and less than or equal to 2 mm.

Illustratively, the materials of the light splitting unit, the curved surface reflecting unit and the lens group comprise glass or optical resin, the refractive index of the materials ranges from 1.5 to 1.95, the thickness H1 of the curved surface reflecting unit is controlled to meet the requirement that H1 is not less than 1 and not more than 5mm and the thickness H2 of the light splitting unit is controlled to meet the requirement that H2 is not less than 0.3 and not more than 2mm by reasonably selecting the materials of the light splitting unit and the curved surface reflecting unit, so that the system is compact and light in structure and the comfort of a wearer is improved.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the utility model. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. An augmented reality display system is characterized by comprising a light splitting unit, a curved surface reflecting unit, a lens group and a display;

the display is used for emitting a first display light beam;

2. The augmented reality display system of claim 1, wherein the lens group further comprises a mirror;

3. The augmented reality display system of claim 1, wherein the beam splitting unit comprises a quarter wave plate, a polarizing reflective film layer, and a beam splitter body, the beam splitter body comprising a first beam splitting face and a second beam splitting face;

4. The augmented reality display system of claim 3, wherein the angle between the optical axis direction of the polarizing reflective film and the optical axis direction of the quarter-wave plate is 45 ° or 135 °.

5. The augmented reality display system of claim 1, wherein the curved reflective unit comprises a first curved surface and a second curved surface;

6. The augmented reality display system of claim 1, wherein the angle between the tangent plane of the center of the curved reflection unit and the plane of the light splitting unit is α, and α is greater than or equal to 30 ° and less than or equal to 60 °.

7. The augmented reality display system of claim 1, wherein the curved reflective element has a focal length relative to the reflected light beam of F2, 20mm ≦ F2 ≦ 35 mm;

8. The augmented reality display system of claim 1, wherein the curved reflective unit has a thickness of H1, H1 5 mm.

9. The augmented reality display system of claim 1, wherein the light-splitting unit has a thickness of H2, H2 ≦ 2mm in 0.3mm ≦ H.

10. The augmented reality display system of claim 1, wherein the first display beam comprises at least one of natural light, linearly polarized light, and elliptically polarized light.