WO2019024090A1

WO2019024090A1 - Optical imaging system and head-mounted device

Info

Publication number: WO2019024090A1
Application number: PCT/CN2017/096034
Authority: WO
Inventors: 李国洲
Original assignee: 深圳市柔宇科技有限公司
Priority date: 2017-08-04
Filing date: 2017-08-04
Publication date: 2019-02-07
Also published as: CN109791298A

Abstract

An optical imaging system (10) and a head-mounted device (100). The optical imaging system (10) comprises a display screen (11) and a first prism (12). The display screen (11) is used to emit image light that carries image information. The first prism (12) comprises a first polarization beam-splitting film (121), a first reflecting surface (122), and a first quarter-wavelength delay film (123). The first quarter-wavelength delay film (123) is disposed between the first polarization beam-splitting film (121) and the first reflecting surface (122). The first polarization beam-splitting film (121) is used for transmitting first-state polarized light and reflecting second-state polarized light. The first quarter-wavelength delay film (123) is used to perform conversion between linear polarization light and circular polarization light and convert the first-state polarized light into the second-state polarized light. The first reflecting surface (122) is used for reflecting the image light.

Description

Optical imaging system and headset

Technical field

The present invention relates to the field of optical imaging technologies, and in particular, to an optical imaging system and a headset.

Background technique

Optical imaging systems for augmented reality glasses are generally classified into a transflective, an optical waveguide, an off-axis mirror, a free-form prism, and the like. Among them, the semi-transverse prism is more common. The smart glasses feature an image projected onto the retina of the human eye through a pico projector and a translucent prism. The light needs to pass through the transflective film twice. Thus, the low utilization of light energy results in a darker picture.

Summary of the invention

Embodiments of the present invention provide an optical imaging system and a head mounted device.

An optical imaging system according to an embodiment of the present invention includes a display screen and a first prism;

The display screen is configured to emit image light that carries image information;

The first prism includes a first polarization splitting film, a first reflective surface, and a first 1/4 wavelength retardation film disposed between the first polarization splitting film and the first reflective surface; The first polarization splitting film is configured to transmit polarized light of the first state and polarized light of the second state, the polarized light of the first state has a first polarization direction, and the polarized light of the second state has a second polarization a direction in which the first polarization direction is perpendicular to the second polarization direction; the first 1/4 wavelength retardation film is used to perform conversion between linearly polarized light and circularly polarized light and to polarize the first state Converting light into polarized light of the second state; the first reflecting surface is for reflecting the image light;

The image light enters the first prism and sequentially passes through the first polarization splitting film, the first quarter-wavelength retardation film, and the first reflective surface, and then the first reflective surface After the reflection, the first 1/4 wavelength retardation film passes again, and is output from the first prism through the first polarization splitting film reflection.

The headset device of the embodiment of the present invention includes:

The optical imaging system; and

A frame on which the optical imaging system is disposed.

The optical imaging system and the headset of the embodiment of the present invention introduce a first 1/4 wavelength retardation film, and at the same time change the transflective film to the first polarization splitting film, thereby improving the utilization of light energy, thereby making the image more Bright and clear.

Additional aspects and advantages of the embodiments of the invention will be set forth in part in the description.

DRAWINGS

The above and/or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the appended claims

1 is a schematic structural view of an optical imaging system according to a first embodiment of the present invention;

Figure 2 is a schematic view showing the manufacturing process of the first prism shown in Figure 1 of the present invention;

3 is a schematic structural view of an optical imaging system according to a second embodiment of the present invention;

4 is a schematic structural view of an optical imaging system according to a third embodiment of the present invention;

Figure 5 is a graph showing a modulation transfer function of the first embodiment of the present invention;

Figure 6 is a graph showing a modulation transfer function of a second embodiment of the present invention;

7 is a schematic structural view of a head wear device according to an embodiment of the present invention;

Description of main components and symbols:

The optical imaging system 10, the display screen 11, the first prism 12, the first polarization splitting film 121, the first reflecting surface 122, the first 1/4 wavelength retardation film 123, the incident surface 124, the exit surface 125, and the second prism 13 a second polarization splitting film 131, a second reflecting surface 132, a second 1/4 wavelength retardation film 133, a light incident surface 134, a light exit surface 135, a polarizing plate 14, a first portion 15, a second portion 16, and a third portion 17. Frame 20, battery 30, microphone 40, speaker 50, processor 60, camera 70, headset 100, human eye 200.

Detailed ways

The embodiments of the present invention are described in detail below, and the examples of the embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals indicate the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are intended to be illustrative of the invention and are not to be construed as limiting.

In the description of the embodiments of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "previous" "," "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. The orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is merely for the convenience of describing the embodiments and the simplified description of the present invention, and does not indicate or imply that the device or component referred to has a specific orientation, The orientation configuration and operation are therefore not to be construed as limiting the embodiments of the invention. Moreover, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" or "second" may include one or more of the described features either explicitly or implicitly. In the description of the embodiments of the present invention, the meaning of "a plurality" is two or more unless specifically defined otherwise.

In the description of the embodiments of the present invention, it should be noted that the terms "installation", "connected", and "connected" are to be understood broadly, and may be fixed connections, for example, or They are detachable or integrally connected; they can be mechanically connected, they can be electrically connected or can communicate with each other; they can be connected directly or indirectly through an intermediate medium, which can be internal or two components of two components. Interaction relationship. For those skilled in the art, the specific meanings of the above terms in the embodiments of the present invention can be understood on a case-by-case basis.

In the embodiments of the present invention, the "on" or "below" of the second feature may include direct contact of the first and second features, and may also include the first sum, unless otherwise specifically defined and defined. The second feature is not in direct contact but through additional features between them. Moreover, the first feature "above", "above" and "above" the second feature includes the first feature directly above and above the second feature, or merely indicating that the first feature level is higher than the second feature. The first feature "below", "below" and "below" the second feature includes the first feature directly below and below the second feature, or merely the first feature level being less than the second feature.

The following disclosure provides many different embodiments or examples for implementing different structures of embodiments of the present invention. In order to simplify the disclosure of embodiments of the present invention, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the invention. In addition, the embodiments of the present invention may repeat reference numerals and/or reference letters in different examples, which are for the purpose of simplicity and clarity, and do not in themselves indicate the relationship between the various embodiments and/or arrangements discussed. . Moreover, embodiments of the present invention provide examples of various specific processes and materials, but one of ordinary skill in the art will recognize the use of other processes and/or the use of other materials.

Referring to FIG. 1, an optical imaging system 10 of an embodiment of the present invention includes a display screen 11 and a first prism 12. The display screen 11 is used to emit image light that carries image information. The first prism 12 includes a first polarization splitting film 121, a first reflecting surface 122, and a first 1/4 wavelength retardation film 123. The first 1/4 wavelength retardation film 123 is disposed between the first polarization splitting film 121 and the first reflection surface 122. The first polarization splitting film 121 is for transmitting polarized light of the first state and reflecting polarized light of the second state. The polarized light of the first state has a first polarization direction. The polarized light of the second state has a second polarization direction. The first polarization direction is perpendicular to the second polarization direction. The first 1/4 wavelength retardation film 123 is for performing conversion between linearly polarized light and circularly polarized light and converting polarized light of the first state into polarized light of the second state. The first reflective surface 122 is for reflecting image light.

When the optical imaging system 10 is in operation, the image light enters the first prism 12 and sequentially passes through the first polarization splitting film 121, the first quarter-wavelength retardation film 123, and the first reflective surface 122, and then the first reflective surface 122. After the reflection, it passes through the first 1/4 wavelength retardation film 123 again, and is reflected from the first prism 12 to the human eye 200 through the first polarization splitting film 121 so that the human eye 200 can see the image information on the display screen 11.

When the image light is polarized light in the s state and the first polarizing beam splitting film 121 can pass the polarized light in the s state, then the The image light can completely pass through the first polarization splitting film 121, that is, there is no light energy loss at this time, and the image light passing through the first polarization splitting film 121 passes through the first 1/4 wavelength retardation film 123 twice. Thus, the image light that has passed through the first quarter-wavelength retardation film 123 becomes the polarized light of the p-state again. Since the first polarization splitting film 121 can only pass the polarized light of the s state, the polarized light of the p state can be completely reflected by the first polarizing beam splitting film 121 to the human eye 200. As such, the optical imaging system 10 has almost no loss of optical energy, making the image brighter and clearer.

Referring to FIG. 1 again, in the embodiment of the present invention, image light carrying image information emitted from each pixel on the display screen 11 enters the first prism 12 and passes through the first polarization splitting film 121, and the first polarizing beam splitting film 121 transmits the polarized light of the first state and reflects the polarized light of the second state. Then, the image light passes through the first 1/4 wavelength retardation film 123, and the first 1/4 wavelength retardation film 123 converts the linearly polarized light into circularly polarized light, and changes the polarization direction of the polarized light of the first state by 45 degrees. After the image light reaches the first reflecting surface 122, it is totally reflected and passes through the first 1/4 wavelength retardation film 123 again, and the first 1/4 wavelength retardation film 123 converts the circularly polarized light into linearly polarized light, and again the first The polarization direction of the polarized light of the state is changed by 45 degrees, that is, the polarization direction of the polarized light of the first state is changed by 90 degrees in total, and the first quarter-wavelength retardation film 123 converts the polarized light of the first state into the second state. polarized light. When the polarized light of the second state reaches the first polarization splitting film 121, it is totally reflected to the human eye 200. In addition, external light can directly pass through the first prism 12 to reach the human eye 200, so that the human eye 200 can not only see the external scene but also the virtual image, thereby generating a feeling of augmented reality. In the embodiment of the present invention, the light energy is hardly lost, the light energy utilization rate is high, and the image seen by the human eye 200 is bright and clear, and the first polarization splitting film 121 and the first quarter-wavelength retardation film 123 are embedded in the first Within the prism 12, an integrated design of the optical imaging system 10 is achieved with a small volume.

In the embodiment of the present invention, the specific position of the first 1/4 wavelength retardation film 123 is not limited, and the first 1/4 wavelength retardation film 123 may be located between the first reflection surface 122 and the first polarization splitting film 121. For example, the first 1/4 wavelength retardation film 123 may be disposed adjacent to the first reflective surface 122, or disposed adjacent to the first polarization splitting film 121, or disposed in the middle of the first reflective surface 122 and the first polarization splitting film 121. .

In some embodiments, the polarized light of the first state is polarized light of the s state, and the polarized light of the second state is polarized light of the p state; or the polarized light of the first state is polarized light of the p state, the second state The polarized light is polarized light in the s state. Referring to FIG. 1, the polarization direction of the polarized light in the s state is perpendicular to the paper surface, and the polarization direction of the polarized light in the p state is in the plane of the paper (parallel to the paper surface).

In one embodiment, the function of the first polarizing beam splitting film 121 may be coordinated with the polarization state of the image light emitted by the display screen 11 when the optical imaging system 10 is manufactured. For example, when the image light emitted by the display screen 11 is polarized light of the s state, the first polarization splitting film 121 is correspondingly designed to transmit the polarized light of the s state and reflect the polarized light of the p state; when the image displayed by the display screen 11 When the light is polarized light of the p state, the first polarization splitting film 121 is correspondingly designed to transmit the polarized light of the p state and reflect the polarized light of the s state.

In some embodiments, the first reflecting surface 122 has a spherical or aspherical surface. Wherein the first reflecting surface 122 is used to achieve primary amplification and correction of aberrations.

Preferably, the surface of the first reflecting surface 122 may be aspherical.

Specifically, the aspherical edge has a low aberration, and the imaging is more natural and realistic, and has a clearer and more comfortable visual effect.

In some embodiments, the material of the first prism 12 is optical plastic polymethylmethacrylate (PMMA).

Specifically, the first prism 12 made of PMMA is light in weight, low in cost, and mature in processing. When the first reflecting surface 122 is a plastic aspherical surface, the first reflecting surface 122 can better correct the aberration.

In some embodiments, the first reflective surface 122 can be convex.

Referring to FIG. 2, in some embodiments, when manufacturing the first prism 12, the first reflective surface 122 is first injection molded on the prism, and then the prism is cut into three parts, as shown in FIG. 2, from left to right. The right portion is the first portion 15, the second portion 16, and the third portion 17, and then the surfaces of the three portions are coated. For example, a first 1/4 wavelength retardation film 123 is plated on the surface of the first portion 15 that is connected to the second portion 16, and a first polarization beam split is plated on the surface of the second portion 16 that is connected to the third portion 17. Film 121. Finally, the first portion 15, the second portion 16, and the third portion 17 are glued with optical glue to form the first prism 12. Wherein, the refractive index of the optical glue is the same as or similar to the refractive index of the prism, so as to avoid unnecessary reflection or refraction of the image light at each glue of the first prism 12.

Referring to FIG. 1 , in some embodiments, the first prism 12 includes an entrance face 124 and an exit face 125 . The image light enters the first prism 12 from the incident surface 124 and is output by the exit surface 125. The first polarization splitting film 121 forms a first predetermined angle with both the exit surface 125 and the incident surface 124.

Specifically, the image light enters the first prism 12 perpendicularly from the incident surface 124, and the first prism 12 is vertically outputted by the exit surface 125.

In certain embodiments, the first predetermined angle is 45 degrees.

Specifically, the angle formed by the first polarization splitting film 121 and the exit surface 125 is 45 degrees, and the angle formed by the first polarization splitting film 121 and the incident surface 124 is 45 degrees (in the embodiment of the present invention, the incident surface) 124 is perpendicular to the exit surface 125).

Thus, when the image light is output from the first prism 12, the central field of view light of the image light is parallel to the visual axis of the human eye 200, and the human eye 200 is more comfortable to view.

In some embodiments, the first 1/4 wavelength retardation film 123 is perpendicular to the exit surface 125 to avoid unwanted reflection of image light as it passes through the first 1/4 wavelength retardation film 123.

Referring to FIG. 3, in some embodiments, optical imaging system 10 further includes a second prism 13. The second prism 13 is disposed between the display screen 11 and the first prism 12.

Specifically, the image light beam carrying the image information emitted from each pixel on the display screen 11 passes through the second prism 13 and then passes through the first prism 12 to reach the human eye 200. Since the second prism 13 is added to the optical imaging system 10, The degree of freedom of aberration correction can be improved, and the light is folded while increasing the degree of freedom of aberration correction, so that the optical imaging system 10 is compact.

In some embodiments, the second prism 13 includes a second polarization splitting film 131, a second reflective surface 132, and a second 1/4 wavelength retardation film 133. The second 1/4 wavelength retardation film 133 is disposed between the second polarization splitting film 131 and the second reflection surface 132. The second polarization splitting film 131 is for transmitting polarized light of the second state and reflecting polarized light of the first state. The second 1/4 wavelength retardation film 133 is for performing conversion between linearly polarized light and circularly polarized light and converting polarized light of the second state into polarized light of the first state. The second reflective surface 132 is for reflecting image light.

When the optical imaging system 10 is in operation, the image light enters the second prism 13 and passes through the second polarization splitting film 131, the second quarter-wave retardation film 133, and the second reflecting surface 132, and then the second reflecting surface 132. After the reflection, it passes through the second quarter-wave retardation film 133 again, and is reflected from the second prism 13 by the second polarization splitting film 131.

Specifically, the image light carrying the image information emitted from each pixel on the display screen 11 enters the second prism 13 and passes through the second polarization splitting film 131, and the second polarization splitting film 131 transmits the polarized light of the second state, and reflects The first state of polarization. Then, the image light passes through the second quarter-wavelength retardation film 133, which converts the linearly polarized light into circularly polarized light, and changes the polarization direction of the polarized light of the second state by 45 degrees. After the image light reaches the second reflecting surface 132, it is totally reflected and passes through the second quarter-wave retardation film 133 again, and the second quarter-wavelength retardation film 133 converts the circularly polarized light into linearly polarized light, and again the second The polarization direction of the polarized light of the state is changed by 45 degrees, that is, the polarization direction of the polarized light of the second state is changed by 90 degrees in total, and the second quarter-wavelength retardation film 133 converts the polarized light of the second state into the first state. polarized light. When the polarized light of the first state reaches the second polarization splitting film 131, it is totally reflected from the second prism 13 and enters the first prism 12. The optical path propagation after the image light enters the first prism 12 is the same as the case where the image light emitted by the display screen 11 in the previous embodiment directly enters the first prism 12, and details are not described herein again.

In the embodiment of the present invention, the specific position of the second 1/4 wavelength retardation film 133 is not limited, and the second 1/4 wavelength retardation film 133 may be located between the second reflection surface 132 and the second polarization splitting film 131. For example, the second 1/4 wavelength retardation film 133 may be disposed adjacent to the second reflective surface 132, or disposed adjacent to the second polarization splitting film 131, or disposed in the middle of the second reflective surface 132 and the second polarization splitting film 131. .

In one embodiment, the functions of the first polarizing beam splitting film 121 and the second polarizing beam splitting film 131 may be coordinated with the polarization state of the image light emitted by the display screen 11 when the optical imaging system 10 is manufactured. For example, when the image light emitted by the display screen 11 is polarized light of the s state, the second polarizing beam splitting film 131 is correspondingly designed to transmit the polarized light of the s state and reflect the polarized light of the p state, and the first polarizing beam splitting film 121 Correspondingly, it is designed to transmit polarized light of the p-state and reflect the polarized light of the s state; when the image light emitted by the display screen 11 is polarized light of the p-state, the second polarizing beam splitting film 131 is correspondingly designed to transmit the polarization of the p-state. Light reflects the polarized light in the s state, and the first polarizing beam splitting film 121 is correspondingly designed to transmit polarized light in the s state and reflect the polarized light in the p state.

In some embodiments, the second reflecting surface 132 has a spherical or aspherical surface. The second reflecting surface 132 is used to achieve secondary amplification and correct aberration.

Preferably, the surface of the second reflecting surface 132 may be aspherical.

Specifically, the aspherical edge has a low aberration, and the imaging is more natural and realistic, and has a clearer and more comfortable visual effect. In addition, since an aspherical surface is added to the optical imaging system 10 (the first reflective surface 122 is aspherical, and the second reflective surface 132 is also aspherical), it is easier to correct aberrations, and a larger angle of view can be realized. The field angle can reach 25 degrees).

In some embodiments, the material of the second prism 13 is an optical plastic polymethylmethacrylate (PMMA).

Specifically, the second prism 13 made of PMMA is light in weight, low in cost, and mature in processing. When the second reflecting surface 132 is a plastic aspherical surface, the second reflecting surface 132 can better correct the aberration.

In some embodiments, the second reflective surface 132 can be a concave surface.

In some embodiments, when the second prism 13 is manufactured, the second reflecting surface 132 is first injection molded on the prism, then the prism is cut into three parts, and then the surface of the three parts is coated, and finally, optical The glue glues the three parts to form the second prism 13. The manufacturing method of the second prism 13 is the same as that of the first prism 12, and will not be described herein.

Referring to FIG. 3, in some embodiments, the second prism 13 includes a light incident surface 134 and a light exit surface 135. The image light enters the second prism 13 from the light incident surface 134 and is output by the light exit surface 135. The second polarization splitting film 131 forms a second predetermined angle with the light exit surface 135 and the light incident surface 134.

Specifically, the image light rays vertically enter the second prism 13 from the light incident surface 134, and the second prism 13 is vertically outputted by the light exit surface 135.

In certain embodiments, the second predetermined angle is 45 degrees.

Specifically, the angle formed by the second polarization splitting film 131 and the light exit surface 135 is 45 degrees, and the angle formed by the second polarization splitting film 131 and the light incident surface 134 is 45 degrees (in the embodiment of the present invention, The smooth surface 134 is perpendicular to the light exit surface 135).

It should be noted that the light-emitting surface 135 of the second prism 13 is disposed in parallel with the incident surface 124 of the first prism 12, so that the image light vertically outputted from the light-emitting surface 135 can vertically enter the incident surface 124 to prevent the image light from being outputted. Unnecessary reflection occurs in the process of the prism 26 and entering the first prism 12.

In some embodiments, the second 1/4 wavelength retardation film 133 is perpendicular to the light exit surface 135 to prevent unwanted reflection of image light as it passes through the second quarter wavelength retardation film 133.

In some embodiments, the display screen 11 is a liquid crystal display (LCD) or a liquid crystal on silicon (LCOS) display.

Specifically, when the image light emitted by the LCD and the LCOS is linearly polarized light, the LCD and the LCOS can further cause the LCD and the LCOS to emit linearly polarized light of the s state or linearly polarized light of the p state. As such, when the optical imaging system 10 includes only the first prism 12, there is no light loss when the image light passes through the first polarization splitting film 121 and the first 1/4 wavelength retardation film 123. When the optical imaging system 10 includes both the first prism 12 and the second prism 13, the image light passes through the second polarization splitting film 131, the second quarter-wave retardation film 133, the first polarization splitting film 121, and the first one. There is no light loss in the /4 wavelength retardation film 123.

Referring again to FIG. 1, in one embodiment, the display screen 11 is an LCD, and the optical imaging system 10 includes only a first prism 12 for emitting linearly polarized light in an s state, and a first polarizing beam splitting film 121 for transmitting The polarized light of the s state reflects the polarized light of the p state. When the linearly polarized light of the s state emitted by the LCD passes through the first polarization splitting film 121, all of the transmission occurs, and then passes through the first 1/4 wavelength retardation film 123, and the linearly polarized light is all converted into circularly polarized light, and the polarization direction is changed. After 45 degrees, after being reflected by the first reflecting surface 122, the image light passes through the first 1/4 wavelength retardation film 123 again, and the circularly polarized light is converted into linearly polarized light, and the polarization direction is again changed by 45 degrees, and the linear polarization of the s state. The light becomes linearly polarized light of the p state, and when the linearly polarized light of the p state passes through the first polarization splitting film 121, all of the reflections reach the human eye 200. During this light propagation, there is almost no loss of light energy, and the utilization of light energy is high, and the image seen by the human eye 200 is bright and clear.

Referring again to FIG. 3, in one embodiment, the display screen 11 is an LCD, and the optical imaging system 10 includes a first prism 12 and a second prism 13 for transmitting s-state linearly polarized light and second polarization splitting. The film 131 is for transmitting polarized light of the s state and reflecting polarized light of the p state, and the first polarizing beam splitting film 121 is for transmitting polarized light of the p state and reflecting polarized light of the s state. When the linearly polarized light of the s state emitted by the LCD passes through the second polarization splitting film 131, all of the transmission occurs, and then passes through the second quarter-wavelength retardation film 133, and the linearly polarized light is all converted into circularly polarized light, and the polarization direction is changed. After 45 degrees, after being reflected by the second reflecting surface 132, the image light passes through the second quarter-wave retardation film 133 again, and the circularly polarized light is converted into linearly polarized light, and the polarization direction is again changed by 45 degrees, and the linear polarization of the s state. The light becomes linearly polarized light of the p state, and when the linearly polarized light of the p state passes through the second polarization splitting film 131, it is totally reflected, is output from the second prism 13, and enters the first prism 12. When the linearly polarized light of the p-state passes through the first polarization splitting film 121, all of the transmission occurs, and then passes through the first quarter-wavelength retardation film 123, and the linearly polarized light is all converted into circularly polarized light, and the polarization direction is changed by 45 degrees. After being reflected by the first reflecting surface 122, the image light passes through the first 1/4 wavelength retardation film 123 again, the circularly polarized light is converted into linearly polarized light, the polarization direction is changed again by 45 degrees, and the p-state linearly polarized light becomes The linearly polarized light of the s state, when the linearly polarized light of the s state passes through the first polarization splitting film 121, is totally reflected to reach the human eye 200. In this light propagation process, there is almost no loss of light energy, the light energy utilization rate is high, the image seen by the human eye 200 is bright and clear, and the degree of freedom of aberration correction is improved.

It can be understood that the case where the LCD is used to emit the linearly polarized light of the p state is similar to the above two embodiments, and will not be developed in detail here.

Referring to FIG. 4, in some embodiments, the display 11 is an Organic Light-Emitting Diode (OLED) display.

Thus, the selection of the display screen 11 is diverse and the application range is wide.

In some embodiments, when display screen 11 is an OLED display screen, optical imaging system 10 further includes a polarizer 14 disposed between display screen 11 and second prism 13. Polarizer 14 is used to convert image light into polarized light.

Specifically, the image light emitted by the OLED display screen includes polarized light and unpolarized light. The polarizing plate 14 disposed between the OLED display and the second prism 13 converts the unpolarized light emitted by the OLED display into polarized light. Since the polarized light of the p state and the polarized light of the s state may exist in the polarized light, there may be a certain loss of optical energy when the image light passes through the second polarizing beam splitting film 131, but compared with the conventional augmented reality. The optical imaging system of the glasses still has a higher utilization rate of light energy, and the image seen by the human eye 200 is brighter and clearer.

Referring to FIG. 5 and FIG. 6, the modulation transfer function (MTF) is a comprehensive evaluation index of the performance of the optical system, and represents the ratio of the contrast of the image to the contrast (ordinate) of the object at a certain spatial frequency (abscissa). The smoother the curve, the larger the area enclosed by the horizontal axis, the more the amount of image information transmitted by the optical imaging system 10, the better the image quality, and the clearer the image. Wherein, 7.5 degrees is half of the maximum angle of view. As can be seen from FIGS. 5 and 6, the field of view of the optical imaging system 10 composed of a plurality of aspherical surfaces (the first reflecting surface 122 and the second reflecting surface 132) can be achieved. 20 degrees (Fig. 6, in the case where the amount of image information is larger than a certain value, half of the maximum angle of view can reach 10 degrees), and the field of view of the optical imaging system 10 of a single aspherical surface (first reflecting surface 122) is only 15 degrees (Fig. 5, in the case where the amount of image information is larger than a certain value, half of the maximum angle of view can reach 7.5 degrees), and the imaging quality of the edge field of view is not imaged by the optical imaging system 10 composed of a plurality of aspherical surfaces. Good quality. In summary, an optical imaging system 10 comprised of multiple aspherical surfaces is much better in terms of achievable field of view and imaging quality than a single aspheric optical imaging system 10.

Referring to FIGS. 1 and 7, a headset 100 of an embodiment of the present invention includes the optical imaging system 10 and the frame 20 of any of the above embodiments. The optical imaging system 10 is disposed on the frame 20.

The headgear device 100 of the embodiment of the present invention introduces the first 1/4 wavelength retardation film 123, and simultaneously changes the transflective film to the first polarization splitting film 121, which is compared with the image ray for the first time. In the case of a semipermeable membrane, the semi-transmissive film transmits a portion of the image light toward the reflecting surface 122 and reflects another portion of the image light in a direction opposite to the human eye 200. When the image light passes through the semi-transparent film for the second time, half The trans-transmissive film transmits a portion of the image light toward the incident surface 124 and reflects the remaining portion of the image light in the direction of the human eye 200. The first polarizing beam splitting film 121 can transmit all of the image light (the first state of polarized light). All are transmitted and eventually reflected into the human eye 200. As such, the headgear device 100 of the present invention increases the utilization of light energy, thereby making the image brighter and clearer.

In one embodiment, the display screen 11 can be integrated within the frame 20. When the optical imaging system 10 includes the first prism 12, the first prism 12 projects from the frame 20. When the optical imaging system 10 includes the first prism 12 and the second prism 13, the second prism 13 can be integrated into the display screen 11, and the first prism 12 projects from the frame 20.

In some embodiments, the head mounted device 100 further includes a battery 30. Battery 30 is used to power headset device 100.

Among them, the battery 30 can also be integrated in the frame 20.

In some embodiments, the headset 100 further includes a microphone 40, a speaker 50, and a processor 60. The microphone 40 is for receiving the voice of the user. The speaker 50 is used to amplify the sound. The processor 60 is configured to recognize a voice to generate a control command, and control the headset device 100 to perform an operation corresponding to the control command according to the control command.

For example, the user's voice may be "turn off the headset", then the processor 60 recognizes the voice to generate a control command and controls the headset 100 to shut down in accordance with the control command.

The microphone 40, the speaker 50 and the processor 60 can all be integrated in the frame 20.

It is to be noted that the sound amplified by the speaker 50 may include the voice of the user and the sound in the video played by the headset 100.

In some embodiments, the head mounted device 100 further includes a camera 70 and a processor 60. The camera 70 is used to acquire image information. The processor 60 is configured to control the display screen 11 to emit image light that carries image information.

Specifically, the image information in the image light emitted by the display screen 11 may be image information acquired by the camera 70 in real time, or may be image information acquired by the headset 100 and the terminal or the cloud through wifi or Bluetooth communication.

The camera 70 and the processor 60 can both be integrated in the frame 20.

In some embodiments, the processor 60 includes a Global Positioning System (GPS), and the processor 60 can acquire image information corresponding to different positioning information from the terminal or the cloud according to different positioning information of the GPS, thereby controlling the display screen 11 An image light that carries the image information is emitted.

In the present specification, the schematic representation of the above terms does not necessarily mean the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described, it is understood that the above-described embodiments are illustrative and are not to be construed as limiting the scope of the invention. Implementations are subject to change, modification, replacement, and variations.

Claims

An optical imaging system, comprising: a display screen and a first prism;

The display screen is configured to emit image light that carries image information;

The first prism includes a first polarization splitting film, a first reflective surface, and a first 1/4 wavelength retardation film disposed between the first polarization splitting film and the first reflective surface; The first polarization splitting film is configured to transmit polarized light of the first state and polarized light of the second state, the polarized light of the first state has a first polarization direction, and the polarized light of the second state has a second polarization a direction in which the first polarization direction is perpendicular to the second polarization direction; the first 1/4 wavelength retardation film is used to perform conversion between linearly polarized light and circularly polarized light and to polarize the first state Converting light into polarized light of the second state; the first reflecting surface is for reflecting the image light;

The image light enters the first prism and sequentially passes through the first polarization splitting film, the first quarter-wavelength retardation film, and the first reflective surface, and then the first reflective surface After the reflection, the first 1/4 wavelength retardation film passes again, and is output from the first prism through the first polarization splitting film reflection.
The optical imaging system according to claim 1, wherein said first prism comprises an incident surface and an exit surface, said image light entering said first prism from said incident surface and outputted by said exit surface The first polarization splitting film forms a first predetermined angle with the exit surface and the incident surface.
The optical imaging system of claim 2 wherein said first predetermined angle is 45 degrees.
The optical imaging system of claim 1 wherein said optical imaging system further comprises a second prism disposed between said display screen and said first prism.
The optical imaging system according to claim 4, wherein said second prism comprises a second polarization splitting film, a second reflecting surface, and said second polarizing beam splitting film and said second reflection a second quarter-wavelength retardation film between the faces; the second polarizing beam splitting film is configured to transmit the polarized light of the second state to reflect the polarized light of the first state; the second quarter a wavelength retardation film for converting between linearly polarized light and circularly polarized light and converting polarized light of the second state into polarized light of the first state; the second reflective surface for reflecting the image Light

The image light enters the second prism and sequentially passes through the second polarization splitting film, the second quarter-wave retardation film, and the second reflective surface, and then the second reflective surface After the reflection, the second quarter-wavelength retardation film passes again, and is output from the second prism through the second polarization splitting film reflection.
The optical imaging system according to claim 5, wherein said second prism comprises a light incident surface and a light exiting surface, said image light rays entering said second prism from said light incident surface, and said light exiting The second polarization splitting film forms a second predetermined angle with the light exit surface and the light incident surface.
The optical imaging system of claim 6 wherein said second predetermined angle is 45 degrees.
The optical imaging system according to any one of claims 1 to 7, wherein the display module is a liquid crystal display or a liquid crystal display.
The optical imaging system according to any one of claims 1 to 7, wherein the display module is an organic light emitting diode display.
The optical imaging system of claim 9 further comprising a polarizer disposed between said display module and said second prism, said polarizer for said image Light is converted to polarized light.
A head mounted device, comprising:

The optical imaging system of claim 1;

A frame on which the optical imaging system is disposed.
The headgear according to claim 11, wherein the first prism comprises an incident surface and an exit surface, and the image light enters the first prism from the incident surface and is output by the exit surface The first polarization splitting film forms a first predetermined angle with the exit surface and the incident surface.
The headgear according to claim 12, wherein said first predetermined angle is 45 degrees.
The headgear according to claim 11, wherein said optical imaging system further comprises a second prism disposed between said display screen and said first prism.
The headgear according to claim 14, wherein said second prism comprises a second polarization a splitting film, a second reflecting surface, and a second quarter-wavelength retardation film disposed between the second polarizing beam splitting film and the second reflecting surface; the second polarizing beam splitting film for transmitting The polarized light of the second state reflects the polarized light of the first state; the second quarter-wavelength retardation film is used for performing conversion between linearly polarized light and circularly polarized light and the second state Converting polarized light into polarized light of the first state; the second reflecting surface is for reflecting the image light;

The image light enters the second prism and sequentially passes through the second polarization splitting film, the second quarter-wave retardation film, and the second reflective surface, and then the second reflective surface After the reflection, the second quarter-wavelength retardation film passes again, and is output from the second prism through the second polarization splitting film reflection.
The headgear according to claim 15, wherein the second prism comprises a light incident surface and a light exiting surface, and the image light rays enter the second prism from the light incident surface, and the light is emitted by the light incident The second polarization splitting film forms a second predetermined angle with the light exit surface and the light incident surface.
The headgear according to claim 16, wherein said second predetermined angle is 45 degrees.
A head mounted device according to any one of claims 11-17, wherein the display screen is a liquid crystal display or a liquid crystal display.
A head mounted device according to any one of claims 11-17, wherein the display screen is an organic light emitting diode display screen, the optical imaging system further comprising a display screen and the second prism A polarizing plate is used to convert the image light into polarized light.
The headgear according to claim 11, wherein the headset further comprises a camera for acquiring the image information, and the processor for controlling the display to transmit The image light of the image information.