WO2023207954A1 - 微型投射模组及头戴显示设备 - Google Patents

微型投射模组及头戴显示设备 Download PDF

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Publication number
WO2023207954A1
WO2023207954A1 PCT/CN2023/090522 CN2023090522W WO2023207954A1 WO 2023207954 A1 WO2023207954 A1 WO 2023207954A1 CN 2023090522 W CN2023090522 W CN 2023090522W WO 2023207954 A1 WO2023207954 A1 WO 2023207954A1
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WO
WIPO (PCT)
Prior art keywords
lens
projection
light
sub
polarized
Prior art date
Application number
PCT/CN2023/090522
Other languages
English (en)
French (fr)
Inventor
刘冰玉
李潍
杜佳玮
李泓
Original Assignee
宁波舜宇光电信息有限公司
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Publication of WO2023207954A1 publication Critical patent/WO2023207954A1/zh

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Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • G03B21/142—Adjusting of projection optics
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B27/017—Head mounted
    • G02B27/0172—Head mounted characterised by optical features
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/28—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/28—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising
    • G02B27/283—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising used for beam splitting or combining
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/28—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising
    • G02B27/283—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising used for beam splitting or combining
    • G02B27/285—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 for polarising used for beam splitting or combining comprising arrays of elements, e.g. microprisms
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • G03B21/20—Lamp housings
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • G03B21/20—Lamp housings
    • G03B21/206—Control of light source other than position or intensity
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • G03B21/20—Lamp housings
    • G03B21/2066—Reflectors in illumination beam
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • G03B21/20—Lamp housings
    • G03B21/2073—Polarisers in the lamp house
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B27/017—Head mounted
    • G02B2027/0178—Eyeglass type

Definitions

  • the present invention relates to the field of optical imaging technology, and in particular to a micro-projection module and a head-mounted display device including the micro-projection module.
  • Augmented Reality (AR) technology is a new technology that "seamlessly" integrates real-world information and virtual-world information. It integrates physical information that is difficult to experience within a certain time and space in the real world. , through computer and other science and technology, simulation and then superposition, so that people can obtain a sensory experience that transcends reality. Due to the feature of augmented reality technology, which superimposes virtual objects or images in the real environment, it has shown great application potential in many fields.
  • the projection module that is, the optical machine, is a key device in augmented reality technology. Its imaging quality and size directly determine the quality of the user experience. How to find a balance between good imaging quality and compact size has always been a major concern. One of the key points that manufacturers pay attention to.
  • micro-projection display chips include TFT-LCD, LCoS, DMD and MicroLED chips.
  • Monochromatic MicroLED light engines have become the darling of the market due to their lightweight characteristics.
  • full-color AR products are still an industry trend.
  • MicroLED chips are limited by material technology and quantum dot conversion technology bottlenecks, and cannot solve the problem of red chip luminous efficiency in the short term.
  • full-color AR light machines based on MicroLED chips cannot be implemented, and RGB full-color MicroLED chips cannot be launched in the short term. product.
  • TFT-LCD chips have the disadvantages of low contrast, low light energy utilization, low brightness and low resolution.
  • the best technical solutions for full-color AR products can only choose LCoS or DLP solutions based on DMD chips. .
  • the two are comparable, and the DMD chip is slightly better than the LCoS chip.
  • LCoS optical machines have a more significant advantage in terms of cost.
  • LCoS optical machines usually set the lighting system and projection system on both sides of the PBS prism. Due to the optical focal length limitation, the lighting, relay and projection systems have a limit length. The overall optical machine has a linear structure, which is difficult to reduce in size and cannot be used. To meet the trend of near-eye display devices becoming increasingly smaller and lighter, a small-sized, lightweight micro-projection module is needed to meet market demand.
  • the purpose of this application is to provide a micro projection module and a head-mounted display device that can meet the market trend of miniaturization and lightweight.
  • Another object of the present application is to provide a micro-projection module and a head-mounted display device, which can help improve the image quality of the lens.
  • a micro projection module including:
  • a lighting component configured to provide polarized illumination light
  • a display chip configured to modulate the polarized illumination light into a polarized image light
  • a projection component configured to project the polarized image light into an image
  • a relay component configured to transmit the polarized illumination light to the display chip and transmit the polarized image light to the projection component, the relay component including a polarizing light splitting component having A first side, from which the polarized image light enters the projection component;
  • the projection assembly includes a third projection sub-lens for light path correction, the third projection sub-lens is opposite to the first side, and the two are separated and spaced apart.
  • the projection assembly further includes a lens barrel for accommodating the third projection sub-lens, the third projection sub-lens is supported by the lens barrel and passes through the lens barrel.
  • the lens barrel remains in the preset position.
  • a composite structure for adjusting the optical path is provided between the third projection sub-lens and the first side, and the composite structure is attached to the first side, so A glass plate is provided on one side of the composite structure facing the third projection sub-lens, and the glass plate covers the composite structure.
  • the composite structure includes at least two layers of composite films arranged in a stack, and the composite films are used for compensation and eccentric light filtering.
  • At least two layers of the composite film include a stacked quarter-wave plate and a polarizing plate.
  • the display chip is an LCoS chip.
  • the display chip and the illumination light source are disposed on the same side of the polarization light splitting component
  • the polarization light splitting component includes a first right-angle prism, a second right-angle prism and a polarization beam splitter.
  • the light splitting element, the first right-angle prism includes the first side surface, the first inclined surface and the first bottom surface
  • the second right-angled prism includes the second side surface, the second inclined surface and the second bottom surface, the first inclined surface and
  • the second inclined surfaces are arranged oppositely
  • the polarizing light splitting element is arranged between the first inclined surface and the second inclined surface.
  • the polarizing light splitting element is used to reflect polarized light with a first polarization state and transmit polarized light with a second polarization state.
  • the second side is opposite to the lighting component to receive the polarized lighting light from the lighting component.
  • the relay component includes at least one first projection sub-lens and at least one second projection sub-lens, and the at least one first projection sub-lens is disposed on the polarization splitter.
  • the optical path between the component and the display chip is configured to provide a transmission path for the polarized illumination light and the polarized image light and perform optical path correction;
  • the at least one first projection sub-lens and the at least one The second projection sub-lens is disposed on different sides of the polarizing beam splitting component and is configured to correct the optical path at least twice, wherein the at least one second projection sub-lens is configured to achieve optical path correction and reflection at the same time. Function; the at least one first projection sub-lens, the at least one second projection sub-lens, and the third projection sub-lens jointly meet the projection requirements of the optical system.
  • the illumination assembly includes: an illumination light source configured to emit multiple channels of monochromatic illumination light; a collimating device; a color combination device; a polarizing device; and a reflection device; wherein the collimating device and the color combining device are disposed in the light path between the illuminating light source and the polarizing device, and are configured to collimate the multiple monochromatic illuminating lights into one combined Color illumination light, the polarizing device is configured to polarize the combined color illuminating light into the polarized illuminating light, and the reflective device is disposed in the light path between the polarizing device and the relay component , configured to transmit the polarized illuminating light to the relay component in a total reflection manner.
  • a head-mounted display device which includes at least one of the micro-projection modules; and, at least one optical waveguide.
  • a micro projection module including:
  • a lighting component configured to provide polarized illumination light
  • a display chip configured to modulate the polarized illumination light into a polarized image light
  • a projection component configured to project the polarized image light into an image
  • a relay component configured to transmit the polarized illumination light to the display chip, and transmit the polarized image light to the projection component
  • the relay component includes a polarization splitting component and at least one second projection sub-assembly.
  • the polarization beam splitting component has a first bottom surface
  • the polarized image light is adapted to reach the second projection sub-lens through the first bottom surface
  • the at least one second projection sub-lens is configured to realize the light path simultaneously
  • the relay component further includes a phase retarder disposed between the first bottom surface and the second projection sub-lens;
  • the difference percentage between the refractive index of the second projection sub-lens and the refractive index of the phase retarder does not exceed 30%
  • the second projection sub-lens and the phase retarder are connected through optical glue, and the difference percentage between the refractive index of the second projection sub-lens and the refractive index of the optical glue does not exceed 30%.
  • the difference percentage between the refractive index of the second projection sub-lens and the refractive index of the phase retarder does not exceed 10%, and/or, the refractive index of the second projection sub-lens
  • the refractive index differs by no more than 10% from the refractive index of the optical glue.
  • the difference percentage between the refractive index of the second projection sub-lens and the refractive index of the phase retarder does not exceed 1%, and/or, the refractive index of the second projection sub-lens
  • the refractive index differs by no more than 1% from the refractive index of the optical glue.
  • the phase retarder is attached to the first bottom surface.
  • the second projection sub-lens includes a second sub-lens optical surface away from the polarization beam splitting component, and the second sub-lens optical surface is a reflective surface.
  • the phase retarder is a quarter wave plate.
  • the display chip and the illumination light source are disposed on the same side of the polarization light splitting component
  • the polarization light splitting component includes a first right-angle prism, a second right-angle prism and a polarization beam splitter.
  • the light splitting element, the first right-angle prism includes the first side surface, the first inclined surface and the first bottom surface
  • the second right-angled prism includes the second side surface, the second inclined surface and the second bottom surface, the first inclined surface and
  • the second inclined surfaces are arranged oppositely
  • the polarizing light splitting element is arranged between the first inclined surface and the second inclined surface.
  • the polarizing light splitting element is used to reflect polarized light with a first polarization state and transmit polarized light with a second polarization state.
  • the second side is opposite to the lighting component to receive the polarized lighting light from the lighting component.
  • the relay component includes at least one first projection sub-lens and at least one second projection sub-lens, and the at least one first projection sub-lens is disposed on the The optical path between the polarization splitting component and the display chip is configured to provide a transmission path for the polarized illumination light and the polarized image light and perform optical path correction; the at least one first projection sub-lens and the At least one second projection sub-lens is disposed on different sides of the polarization splitting component and is configured to correct the optical path at least twice, wherein the at least one second projection sub-lens is configured to correct the optical path simultaneously. with the function of reflection; the at least one first projection sub-mirror The head, the at least one second projection sub-lens and the at least one third projection sub-lens jointly meet the projection requirements of the optical system.
  • the display chip is an LCoS chip.
  • a head-mounted display device which includes at least one of the micro-projection modules; and at least one optical waveguide.
  • Figure 1 is a schematic three-dimensional structural diagram of a micro projection module optical system according to some embodiments of the present invention.
  • Figure 2A is a plan front view of a micro projection module optical system according to some embodiments of the present invention.
  • Figure 2B is a planar right side view of the portion within the dotted box in Figure 2A;
  • Figure 3 is a plan front view of a micro projection module optical system according to some variant embodiments of the present invention.
  • Figure 4 is a plan front view of a micro projection module optical system according to other modified embodiments of the present invention.
  • Figure 5 is a plan front view of the optical system of the micro-projection module according to some further modified embodiments of the present invention.
  • Figure 6 is a 3D structural diagram of a micro projection module according to some embodiments of the present invention.
  • FIGS 7A-7C are schematic three-dimensional structural diagrams of AR glasses according to some embodiments of the present invention.
  • the micro-projection module includes a lighting component 10, a relay component 20, a display chip 30 and a projection component 40.
  • the lighting component 10 is used to provide polarized illumination light with the same polarization state.
  • the relay component 20 is used to transmit at least part of the polarized illumination light from the lighting component 10 to the display chip 30 .
  • the display chip 30 is used to modulate the polarized illumination light into polarized image light carrying image information, and transmit the polarized image light to the projection component 40 through the relay component 20 again.
  • the projection component 40 is used to project the modulated polarized image light to other optical components of the head-mounted display device, such as optical waveguides. That is, in the entire optical system, part of the optical paths of the relay system are reused by the lighting system and the projection system.
  • R represents red light
  • G represents green light
  • B represents blue light
  • W represents white light.
  • polarized illumination light in this application is represented by S polarized light/P polarized light
  • polarized image light is represented by S' polarized light/P' polarized light.
  • the solid line in the figure represents the illumination light path
  • the dotted line represents the projection light path.
  • the illumination light path and the optical elements it passes through constitute an illumination system
  • the projection light path and the optical elements it passes through form a projection system, which will not be described again below.
  • Figure 2A is a plan front view of the optical system of the micro projection module
  • Figure 2B is a plan right side view of the portion within the dotted line frame in Figure 2A.
  • the lighting assembly 10 includes an illumination light source 11, a collimating device 12, a color combining device 13, a uniform light device 14, a first relay lens 15, a polarizing device 16 and a reflecting device 17.
  • the illumination light source 11 further includes a first light source 111 and a second light source 112.
  • the first light source 111 can be a green LED
  • the second light source 112 can be a two-in-one red and blue LED. It can be understood that the color, type, quantity and combination of the illumination light sources may also have other conditions, and are not limited in the present invention.
  • the collimating device 12 further includes a first collimating lens group 121 and a second collimating lens group 122.
  • Each of the first collimating lens group 121 and the second collimating lens group 122 includes at least one optical lens, preferably It is an optical lens set composed of a spherical mirror and a cylindrical mirror. It can also be an optical lens set composed of two same types of lenses among spherical mirrors, cylindrical mirrors and aspherical mirrors, or any combination of two types of lenses, that is to say , the surface shape of the optical lenses that make up the collimating lens group is not limited in this application.
  • the color combination device 13 further includes a first selective reflection film 131 , a second selective reflection film 132 and a wedge prism 133 .
  • the first collimating lens group 121 is used to converge, collimate and transmit the light emitted by the first light source 111 to the first selective reflection film 131
  • the second collimating lens group 122 is used to emit light from the second light source 112 The light is converged, collimated, and transmitted to the second selective reflection film 132 .
  • the first selective reflection film 131 is used to reflect blue light and transmit green light
  • the second selective reflection film 132 is used to reflect red light and transmit green light and blue light.
  • the first selective reflection film 131 is disposed on the lower surface of the wedge prism 133 and faces the first light source 111 .
  • the second selective reflection film 132 is disposed on the upper surface of the wedge prism 133 and faces the second light source 112 .
  • the green light emitted by the first light source 111 is collimated by the first collimating lens group 121 and then passes through the first selective reflection film 131, the wedge prism 133 and the second selective reflection film 132 in sequence; the red light emitted by the second light source 112 passes through The second collimating lens group 122 collimates and is reflected by the second selective reflective film 132; the blue light emitted from the second light source 112 is collimated by the second collimating lens group 122 and then passes through the second selective reflective film 132 and the wedge prism in sequence.
  • the uniform light device 14 can be a fly-eye lens or other common light uniform components, used to obtain uniform illumination distribution.
  • the uniform illumination light obtained after passing through the uniform light device 14 is transmitted through the first relay lens 15 and then passes through the polarizing device 16 to become polarized illumination light with a first polarization state.
  • the polarizing device 16 may be a first polarizer configured to only pass polarized light with a first polarization state and block polarized light with a second polarization state.
  • the polarizing device 16 may also be a first polarization multiplexing element, configured to pass only polarized light with a first polarization state and convert polarized light with a second polarization state into polarized light with a first polarization state.
  • the polarization directions of the polarized light with the first polarization state and the polarized light with the second polarization state are perpendicular to each other.
  • the polarized light with the first polarization state may be S light in linearly polarized light
  • the polarized light with the third polarization state may be linearly polarized light
  • the polarized light in the two polarization states may be P light in linearly polarized light.
  • the polarizing device 16 is disposed in the optical path between the first relay lens 15 and the reflective device 17.
  • the polarizing device 16 is implemented as an S polarizer.
  • the reflective device 17 preferably includes a total reflection prism 171, such as a Porro prism.
  • the total reflection prism 171 includes a prism entrance surface 1711, a prism exit surface 1713 perpendicular to the prism entrance surface 1711, and a prism reflection surface 1712 connecting the prism entrance surface 1711 and the prism exit surface 1713.
  • the prism reflection surface 1712 is an inclined total internal reflection surface, and the inclination angle is preferably 45° with the prism incident surface 1711 .
  • the polarizing device 16 can be directly attached to the prism incident surface 1711 .
  • the uniform illumination light after passing through the uniform light device 14 and the first relay lens 15 passes through the polarizing device 16 and is converted into polarized illumination light with a first polarization state.
  • that is, S-polarized light, other natural light and Stray light and the like are blocked by the polarizing device 16 and cannot pass through.
  • the S-polarized light passing through the polarizing device 16 enters the interior of the total reflection prism 171 perpendicularly to the prism incident surface 1711 , undergoes total reflection at the prism reflective surface 1712 , and exits perpendicular to the prism exit surface 1713 before entering the relay component 20 .
  • the reflective device 17 is not limited to being implemented as a total reflection prism 171, but can also be implemented as a plane reflector 172 or any other device with reflective properties.
  • the plane mirror 172 includes a plane mirror reflection surface 1721 , which is tilted toward the direction of the illumination light source 11 and the relay assembly 20 , preferably at an angle of 45°, so that the light from the illumination light source 11 The light can be turned by 90° and enter the relay component 20 horizontally. It is worth mentioning that implementing the reflective device 17 as a total reflection prism 171 has obvious advantages compared to implementing it as a plane reflector 172.
  • the prism incident surface 1711 of the total reflection prism 171 can be the polarizing device 16 and the first relay.
  • the lens 15 provides an installation plane and a reference, so that the polarizing device 16 can be directly attached to the prism incident surface 1711, and then the first relay lens 15 is assembled on the surface of the polarizing device 16 with the polarizing device 16 as the reference. It is helpful to reduce the difficulty of assembly and improve the accuracy of assembly. If the reflective device 17 is implemented as a plane mirror 172, there will be a lack of connection between the plane mirror 172 and other optical components during assembly, and the assembly accuracy will be difficult to control, which may increase the cumulative assembly error. Of course, there will also be errors during the assembly process. Error compensation can be carried out in other ways according to actual conditions, and the specific implementation and assembly method of the reflective device 17 are not limited in the present invention.
  • the relay component 20 further includes a second relay lens 21 , a polarization beam splitter component 22 , a first projection sub-lens 23 , and a reflective polarization component 24 .
  • the polarized illumination light with the first polarization state emitted from the lighting component 10 which is S-polarized light in this optional embodiment, is transmitted through the second relay lens 21 and then enters the polarization splitter component 22 .
  • the polarization beam splitting component 22 further includes a first right-angle prism 221, a second right-angle prism 222, and a polarization beam splitter element 223.
  • the first right-angle prism 221 and the second right-angle prism 222 are both isosceles right-angle prisms.
  • the first right-angle prism 221 includes a first inclined surface 2211, a first side surface 2212, and a first bottom surface 2213.
  • the second right-angle prism 222 includes a second inclined surface 2221, a second side surface 2222, and a second bottom surface 2223.
  • the first inclined surface 2211 and the second inclined surface 2221 are arranged oppositely, and the polarization splitting element 223 is arranged between the first inclined surface 2211 and the second inclined surface 2221.
  • the polarizing beam splitting element 223 can be a polarizing beam splitting film, in which case the polarizing beam splitting component 22 is a PBS prism.
  • a polarizing dichroic film can be coated on the first inclined surface 2211 and then the first right-angled prism 221 and the second inclined surface 2221 of the second right-angled prism 222 can be glued; or the second inclined surface 2221 can be glued together.
  • the polarizing beam splitter is coated and the second right-angle prism 222 and the first bevel 2211 of the first right-angle prism 221 are glued together.
  • the assembled polarization splitter component 22 includes a first side 2212, a first bottom 2213, a second side 2222 and a second bottom 2223.
  • the first side 2212 is opposite and parallel to the second side 2222
  • the first bottom surface 2213 is opposite and parallel to the second bottom surface 2223
  • the first side 2212 connects the first bottom surface 2213 and the second bottom surface 2223, And perpendicular to both.
  • the second side 2222 is used to receive polarized illumination light from the lighting component 10 .
  • the polarized illumination light is reflected at the polarization splitting element 223 and then turns downward at 90° through the second bottom surface 2223 to reach the display chip 30 , and is modulated by the display chip 30
  • the polarized image light whose polarization direction is then changed is reversed again.
  • the polarization direction of the polarized image light is the same as the polarization direction of the polarized illumination light that first enters the polarization beam splitting component 22. It is reflected again at the polarization beam splitting component 223 and then turns 90° to the left through the first side 2212 and enters the projection component. 40.
  • the polarization splitting element 223 is used to reflect polarized light with a first polarization state and transmit polarized light with a second polarization state. In this optional embodiment, it reflects S-polarized light and transmits P-polarized light at the same time.
  • the polarized illumination light from the lighting assembly 10 is S-polarized light.
  • the S-polarized light is incident perpendicularly to the second side surface 2222, enters the second right-angled prism 222, and occurs on the surface of the polarization splitting element 223. After reflection, the reflected S-polarized light is emitted perpendicularly to the second bottom surface 2223 of the second right-angle prism 222 , is transmitted through the first projection sub-lens 23 , reaches the surface of the display chip 30 , and is received by the display chip 30 .
  • the first projection sub-lens is an optical path correction device, that is, a transmissive element with an optical path correction function.
  • the optical path correction function refers to the shaping function of the light source, such as convergence, and in the projection system, it refers to the balancing function of object-image relationship and aberration.
  • the first projection sub-lens 23 is a lens group composed of at least two optical lenses, and the first projection sub-lens 23 is disposed in the optical path between the polarization beam splitting component 22 and the display chip 30 .
  • the first projection sub-lens 23 is disposed outside the second bottom surface 2223, and the optical axis is perpendicular to the second bottom surface 2223.
  • the first projection sub-lens 23 is used to converge and maintain the S-polarized light emitted from the polarization splitting component 22 within a specific range, and transmit it to the display chip 30 . That is, at this time, the light passing through the first projection sub-lens 23 is part of the illumination light path. part.
  • optical lenses of the first projection sub-lens 23 and the optical lenses of the collimating lens group can be cut (D-cut) to reduce the size in the radial direction to avoid spatial interference.
  • the display chip 30 is used to modulate the polarized illumination light into polarized image light carrying image information, and change its polarization state, for example, convert the polarized light with the first polarization state into the polarized light with the second polarization state.
  • the polarization directions of the first polarization state and the second polarization state are perpendicular to each other.
  • the display chip 30 is preferably an LCoS chip. Due to the characteristics of the LCoS chip, the S-polarized light incident on the chip surface is modulated into P'-polarized light carrying image information. It can be understood that since the LCoS chip itself is a polarized light modulation device, there is no need to add additional polarized light modulation devices. If other types of display chips are used, for display chips without polarized light modulation functions, it is necessary to An additional polarized light modulation device is provided on the surface of the chip to modulate the polarization state of the polarized image light.
  • the polarized image light with image information modulated by the display chip 30, in this optional embodiment, that is, the P' polarized light passes through the first projection sub-lens 23 again and is incident perpendicularly to the second bottom surface 2223 of the second right-angle prism 222. It enters the second right-angle prism 222, is transmitted at the polarization splitting element 223, enters the first right-angle prism 221, and then exits perpendicular to the first bottom surface 2213 of the first right-angle prism 221. It can be understood that at this time, the light passing through the first projection sub-lens 23 is part of the projection light path.
  • the first projection sub-lens 23 realizes the correction function for the illumination light path and the projection light path at the same time.
  • Some light paths in the relay system are reused by the illumination system and the projection system, so that the micro projection module The whole is more in line with the conditions of miniaturization.
  • the display chip and the illumination light source are generally distributed on different sides of the polarization light splitting component, but in this application, the display chip 30 and the illumination light source 11 are distributed on the polarization light splitting component.
  • the display chip 30 and the illumination light source 11 are distributed on the polarization light splitting component.
  • the display chip 30 and the illumination light source 11 are distributed on the polarization light splitting component.
  • the display chip 30 and the illumination light source 11 are distributed on the polarization light splitting component.
  • the display chip 30 and the illumination light source 11 are distributed on the polarization light splitting component.
  • the display chip 30 and the illumination light source 11 are distributed on the polarization light splitting component.
  • the display chip 30 and the illumination light source 11 are distributed on the polarization light splitting component.
  • the display chip 30 and the illumination light source 11 are distributed on the polarization light splitting component.
  • the display chip 30 and the illumination light source 11 are distributed on the polarization light splitting component.
  • the display chip 30 and the illumination light source 11 are distributed on the polarization light splitting
  • the circuit board of at least one illumination light source and the circuit board of the display chip are on the same plane and formed integrally. This approach is conducive to reducing the difficulty of circuit design, simplifying circuit distribution, optimizing circuit board structure, while improving product integration, and further miniaturizing micro-projection modules.
  • the relay component 20 further includes a reflective polarization component 24 , which includes a phase retarder 241 and a second projection sub-lens 242 .
  • the phase retarder 241 is disposed between the first bottom surface 2213 of the first right-angle prism 221 and the second projection sub-lens 242 .
  • the second projection sub-lens is also an optical path correction device.
  • the second projection sub-lens 242 can be a single optical lens or a lens group, which can be a spherical lens, an aspheric lens, etc., and its surface shape and type are combined in There are no limitations in the present invention.
  • the second projection sub-lens 242 includes a second sub-lens optical surface 2421 away from the polarization splitting component 22, and the second sub-lens optical surface 2421 is a reflective surface.
  • the second projection sub-lens 242 is disposed outside the first bottom surface 2213, and the optical axis is perpendicular to the first bottom surface 2213.
  • the second projection sub-lens 242 can simultaneously satisfy multiple functions of optical path correction and optical path reflection, and the second projection sub-lens 242 and the display chip 30 are respectively disposed on non-adjacent parts of the polarizing beam splitting component 22 both sides.
  • Phase retarder 241 is preferably implemented as a quarter-wave plate. During the assembly process, the phase retarder 241 can be directly attached to the first bottom surface 2213 of the first right-angle prism 221, and then the second projection sub-lens 242 is disposed on the surface of the phase retarder 241 to reduce installation difficulty.
  • the phase retarder 241 is disposed between the first bottom surface 2213 of the first right-angle prism 221 and the second projection sub-lens 242, that is, the phase retarder 241 is connected to the first right-angle prism 221 respectively.
  • the phase retarder 241 can be directly attached to the first bottom surface 2213 of the first right-angle prism 221, and then the second projection sub-lens 242 is fixed to the surface of the phase retarder 241 by gluing. .
  • the second projection sub-lens 242 uses a material with a refractive index similar to that of the phase retarder 241, and/or the second projection sub-lens 242 uses a material with a refractive index similar to that of the glued optical glue, so as to reduce the refractive index after passing through the phase retarder 241.
  • the polarized reflected light of the phase retarder 241 and the first bottom surface 2213 of the first right-angle prism 221 is reduced to reduce non-imaging stray light caused by the reflected light not being directly emitted from the second projection sub-lens 242, thereby improving the contrast.
  • the difference percentage between the refractive index of the second projection sub-lens 242 and the refractive index of the phase retarder 241 does not exceed 30%. That is, (refractive index of the second projection sub-lens 242 - refractive index of the phase retarder 241 )/refractive index of the second projection sub-lens 242 ⁇ 30%.
  • the percentage difference does not exceed 20%, or 10%, or 5%, or 1%.
  • the difference percentage between the refractive index of the second projection sub-lens 242 and the refractive index of the optical glue used to glue the second projection sub-lens 242 and the phase retarder 241 does not exceed 30%. That is, (refractive index of the second projection sub-lens 242 - refractive index of the optical glue)/refractive index of the second projection sub-lens 242 ⁇ 30%.
  • the percentage difference does not exceed 20%, or 10%, or 5%, or 1%.
  • the P' polarized light emitted from the first bottom surface 2213 of the first right-angle prism 221 passes through the phase retarder 241 and is converted into circularly polarized light. After being transmitted by the second projection sub-lens 242, it is reflected by the second sub-lens optical surface 2421 and is reflected again. Through the phase retarder 241, the polarization direction is changed by 90°, that is, the polarized light with the second polarization state is converted into the polarized light with the first polarization state, which in this optional embodiment corresponds to P' polarized light becoming S' polarization. Light.
  • the S' polarized light is perpendicular to the first bottom surface 2213 of the first right-angle prism 221 and enters the first right-angle prism 221. Reflection occurs at 223, emerges perpendicular to the first side 2212 of the first right-angle prism 221, and is projected through the projection assembly 40 to other optical components of the head-mounted display device, such as optical waveguides.
  • the projection assembly 40 includes at least a third projection sub-lens 41. It can be understood that the third projection sub-lens 41 is also an optical path correction device.
  • the third projection sub-lens 41 includes at least one optical lens.
  • the third projection sub-lens 41 is disposed outside the first side 2212, and the optical axis is perpendicular to the first side 2212.
  • first projection sub-lens 23, the second projection sub-lens 242 and the third projection sub-lens 41 alone can meet the optical requirements of the projection system of the micro-projection module.
  • the first projection sub-lens The joint correction of the optical path by the lens 23, the second projection sub-lens 242 and the third projection sub-lens 41 enables the projection optical path to meet the effective focal length requirement of the entire system.
  • first projection sub-lens 23 must not only cooperate with the second projection sub-lens 242 and the third projection sub-lens 41 to meet the optical parameter requirements of the projection system, but also meet the optical parameter requirements of the lighting system, so that the first The light path inside the projection sub-lens 23 is reused by the lighting system and the projection system.
  • the third projection sub-lens 41 and the first right-angle prism 221 have a split structure, that is, the third projection sub-lens 41 is spaced apart from the first right-angle prism.
  • the outside of the first side surface 2212 of the prism 221 there is a certain gap between the third projection sub-lens 41 and the first side 2212 of the first right-angle prism 221, which avoids the third projection sub-lens 41 to be directly fixed to the third side of the first right-angle prism 221 through gluing or other methods. 2212 on one side.
  • the optical glue is disposed between the third projection sub-lens 41 and the first side 2212. Since The characteristics of the optical glue, on the one hand, will cause a certain assembly tolerance between the third projection sub-lens 41 and the first right-angle prism 221. On the other hand, the uneven thickness of the glue will cause the third projection sub-lens 41 to be eccentric. On the other hand, there will also be a problem that the third projection sub-lens 41 is tilted. Furthermore, the assembly tolerance of the prism will also cause the third projection sub-lens 41 to cause associated eccentricity and tilt problems.
  • the third projection sub-lens 41 and the first right-angle prism 221 are arranged in a split structure, that is, the third projection sub-lens 41 and the first right-angle prism 221 are indirectly fixed.
  • the third projection sub-lens 41 is accommodated in a lens barrel, and the third projection sub-lens 41 is supported and positioned on the first side 2212 of the first right-angle prism 221 through a lens barrel. .
  • the split structure of the present application can weaken the problem of assembly tolerance during the gluing process, so that only the lens barrel itself is assembled. Tolerances improve assembly accuracy. Furthermore, the fit degree between the third projection sub-lens 41 and the lens barrel is higher than the fit degree between the third projection sub-lens 41 and the first right-angle prism 221 , and the tilt of the third projection sub-lens 41 can be reduced during the assembly process. and eccentricity, thereby improving the image quality and yield of the finished lens, and reducing the time and cost of gluing. In this application, fit refers to the tightness and tightness of the fit during assembly.
  • a composite structure is provided between the third projection sub-lens 41 and the first right-angle prism 221.
  • the composite structure includes at least two layers of composite films stacked in a horizontal direction.
  • the composite structure is attached to the first side 2212 of the first right-angle prism 221 and is arranged opposite the third projection sub-lens 41 in the horizontal direction.
  • a glass plate is provided on the side of the composite structure facing the third projection sub-lens 41 , that is, the glass plate is stacked on the composite structure to cover the composite structure. The glass plate can make the surface shape of the composite structure consistent, ensure imaging quality, improve yield and reduce reflection, thereby improving the contrast of the micro-projection module.
  • the composite film can be implemented as a quarter-wave plate and a polarizing plate, or other forms of composite films with compensation and eccentric filtering functions.
  • the combined color illumination light emitted from the color combining device 13 is converted into polarized illuminating light S through the polarizing device 16 along the first direction.
  • the polarized illuminating light S passes through the reflecting device 17 and then turns 90° along the second direction. Entering the polarization light splitting component 22, it turns 90° again in the polarization light splitting component 22 and reaches the display chip 30 along the third direction. It is modulated by the display chip 30 into polarized image light P' and turns 180° along the fourth direction to reach the polarization light splitting component 22 again. After transmission, it enters the reflective polarizing component 24.
  • the polarized image light S' After being modulated by the reflective polarizing component 24, the polarized image light S' is refracted 180° along the fifth direction and enters the polarizing beam splitting component 22 for the third time. After reflection, the polarized image light S' turns 90°. ° Enters the projection component 40 along the sixth direction, and is finally modulated by the projection component 40 to project the projected light from the micro-projection module, forming a complete illumination light path and projection light path, in which the first direction and the third direction are parallel and opposite to each other. direction, the first direction and the sixth direction are perpendicular to each other.
  • the complete projection lens is composed of three projection sub-lenses, at least one projection sub-lens is disposed between the polarization beam splitting component 22 and the display chip 30 , and the other projection sub-lenses are It is arranged on the outside of the other optical surfaces of the polarizing beam splitting component 22 except the optical surface facing the display chip 30.
  • the first projection sub-lens 23 is used not only for the illumination light path, condensing the light, but also for the projection light path.
  • the optical path is folded on the premise of meeting the total optical path requirements, reducing the overall volume; the second projection sub-lens 242 performs reflective folding on the optical path that meets the object-image relationship requirements, shortening half the length of the folded optical path. The volume is further reduced; the third projection sub-lens 41 is used to balance the image quality and expand the light, so that the chip target image is projected out of the optical machine without loss, that is, the first projection sub-lens 23, the second projection sub-lens 242 and the third projection sub-lens 23.
  • the projection sub-lenses 41 jointly meet the projection requirements of the optical system and complete the projection. Compared with the volume of traditional micro-projection modules of 4cc to 6cc, the micro-projection module provided by this application can control the volume to about 2cc, which has obvious miniaturization advantages.
  • the second projection sub-lens 242 can be replaced by a reflector 242A.
  • the reflector 242A includes a reflective surface 2421A.
  • the reflector 242A is only used to refract the light path by 180° and has no other modulation function for the light.
  • the complete projection lens is composed of two projection sub-lenses, namely the first projection sub-lens 23A and the third projection sub-lens 41A.
  • the first projection sub-lens 23A is disposed between the polarization beam splitting component 22 and the display chip 30
  • the third projection sub-lens 41A is disposed on the other side of the polarization beam splitting component 22 .
  • the first projection sub-lens 23A and the third projection sub-lens 41A together form a complete projection system to meet the overall effective focal length requirement. It can be understood that the first projection sub-lens 23A must cooperate with the third projection sub-lens 41A to meet The optical parameter requirements of the projection system must also meet the optical parameter requirements of the lighting system, so that part of the optical path can be reused by the lighting system and the projection system.
  • the number and location of the projection sub-lenses are not limited by the present invention.
  • the projection lens is divided into different numbers of projection sub-lenses according to the optical design requirements of the projection system and lighting system. Arrangement at different locations is easily imaginable by those skilled in the art.
  • the projection assembly 40B further includes an optical path turning element 42B.
  • the optical path turning element 42B is preferably an isosceles right-angle prism, the slope of which is a total internal reflection surface, used to turn the optical path by 90°.
  • the image light projected from the third projection sub-lens 41B is turned by 90° before entering other optical components of the head-mounted display device, such as optical waveguides.
  • the setting direction of the optical path turning component can be determined according to actual needs, so that the light path can be turned upward, downward, or inward or outward perpendicular to the paper surface, thereby increasing the flexibility of the optical machine setting method.
  • the setting direction of the optical path turning component is in There is no restriction on this.
  • the micro-projection module further includes a power supply unit, a housing, structural connectors between optical elements, and a heat dissipation unit. As shown in Figure 6, the micro-projection module 3D structure diagram of the module.
  • the present invention also proposes a head-mounted display device, which includes at least one micro-projection module as described above, at least one lens unit, and a frame for installing the lens unit and the micro-projection module.
  • a head-mounted display device which includes at least one micro-projection module as described above, at least one lens unit, and a frame for installing the lens unit and the micro-projection module.
  • the micro-projection module outputs images according to instructions issued by the computing unit.
  • a head-mounted display device including the micro-projection module will be described in detail below.
  • AR glasses include a micro-projection module 1, a frame 2 for installing a lens unit, a left lens unit 3, a right lens unit 4, a computing unit 5, and temples 6 for wearing.
  • the left lens unit 3 and the right lens unit 4 are fixedly installed in the frame 2, and the temples 6 can be connected to the frame 2 in any way, such as in a flexible way, or in a folding form, or in a fixed way, Or in a detachable manner, forming the main part of AR glasses.
  • the electronic components of the AR glasses can be selectively installed on the temples 6 and/or the frame 2, or embedded/buried in their materials.
  • the electronic components include but are not limited to the computing unit 5 for processing data and image information, eye trackers, depth sensors, spatial sensors, position sensors and their combinations.
  • the left lens unit 3 and the right lens unit 4 are a common component of an integral optical waveguide, that is, the left lens unit 3 and the right lens unit 4 have a continuous line above the nose pads. area, and the coupling area is provided in this continuous area, and the coupling area is used to propagate light in the direction of the left lens unit 3 and the right lens unit 4 simultaneously.
  • the number of the micro-projection module 1 is one, and it is installed near the nose pad position in the middle of the frame 2. Its light output area is set corresponding to the coupling area of the optical waveguide.
  • the modulated light projected by the micro-projection module is suitable for the left and right eyes.
  • the image light received at the same time is coupled into the optical waveguide as coupling light. After turning and pupil expansion, it is coupled out from the coupling area and is finally received by the user's eyes. That is, a single optical machine is equipped with a single optical waveguide, and the coupling is simultaneously transmitted from the middle to both sides. Image light.
  • the left lens unit 3 and the right lens unit 4 are independent two-light waveguides.
  • the upper right corner of the left lens unit 3 and the upper left corner of the right lens unit 4 each have a coupling area.
  • the coupling area is used to propagate light toward the left lens unit 3 and the right lens unit 4 respectively.
  • the number of micro-projection modules 1 is two, and they are installed near the nose pad position in the middle of the frame 2.
  • the light-emitting areas of the two micro-projection modules are respectively arranged corresponding to the coupling areas of the left and right lens units.
  • the two left and right micro-projection modules are respectively arranged. Projects image light suitable for being received by the left eye and image light suitable for being received by the right eye.
  • the modulated image light is coupled into the optical waveguide as coupling light, and is coupled out from the coupling area after turning and dilating the pupil. Finally, it is received by the user's eyes, that is, a dual-optical machine is equipped with dual optical waveguides to transmit and couple the image light from the corner to the center.
  • the left lens unit 3 and the right lens unit 4 are independent two-light waveguides, and the left middle position of the left lens unit 3 and the right middle position of the right lens unit 4 each have a coupling
  • the coupling area is used to propagate light toward the left lens unit 3 and the right lens unit 4 respectively.
  • the number of the micro-projection modules 1 is two, and they are installed on the temples 6 close to the frame 2.
  • the light-emitting areas of the two micro-projection modules are corresponding to the coupling areas of the left and right lens units.
  • the two left and right micro-projection modules are respectively arranged. Projects image light suitable for being received by the left eye and image light suitable for being received by the right eye.
  • the modulated image light is coupled into the optical waveguide as coupling light, and is coupled out from the coupling area after turning and dilating the pupil. Finally, it is received by the user's eyes, that is, a dual-optical machine is equipped with dual optical waveguides to transmit and couple the image light from the edge to the center.
  • the shape of other lens units, the location of the coupling area, and the location of the micro-projection module can also be considered.
  • the present invention does not impose any restrictions on this.

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Abstract

本申请公开了一种微型投射模组以及头戴显示设备，该微型投射模组包括：照明组件，被配置为提供一偏振照明光；显示芯片，被配置为将偏振照明光调制成一偏振图像光；投影组件，被配置为将偏振图像光投射成像；中继组件，被配置为将偏振照明光传输至显示芯片，以及将偏振图像光传输至投影组件，中继组件包括偏振分光组件，偏振分光组件具有第一侧面，偏振图像光从第一侧面进入投影组件；投影组件包括用于光路矫正的第三投影子镜头，第三投影子镜头与第一侧面相对，二者分体且间隔地设置。本申请的设置方式可以减小第三投影子镜头倾斜和偏心的影响，进而提升镜头成品像质和良率，减少胶合的时间和费用成本。

Description

微型投射模组及头戴显示设备 技术领域
本发明涉及光学成像技术领域，尤其涉及一种微型投射模组以及包括微型投射模组的头戴显示设备。
背景技术
增强现实(Augmented Reality，简称AR)技术，是一种将真实世界信息与虚拟世界信息“无缝”集成的新技术，是把原本在现实世界的一定时间空间范围内很难体验到的实体信息，通过电脑等科学技术，模拟仿真后再叠加，从而使人们获得超越现实的感官体验。由于增强现实技术在真实的环境中叠加虚拟的物体或者画面这一特性，使其在众多领域表现出了巨大的应用潜力。
投射模组，即光机，作为增强现实技术中的关键器件，其成像质量与体积大小直接决定了用户体验的好坏，如何在良好的成像质量与小巧的体积之间寻求平衡一直是各大厂商所关注的重点之一。
近年来，随着微型显示芯片技术的发展，目前主流的微投显示芯片有TFT-LCD、LCoS、DMD以及MicroLED芯片。单色MicroLED光机凭借其轻便的特性成为市场的宠儿。然而，由于单色AR产品存在较大的应用限制，也无法满足已经习惯绚丽画面的消费者对AR产品的期待，全彩AR产品依旧是行业趋势。而MicroLED芯片受限于材料技术和量子点转换技术瓶颈，短期内无法解决红色芯片发光效率的问题，导致基于MicroLED芯片的全彩AR光机无法落地，RGB全彩MicroLED芯片也无法在短期内推出产品。而TFT-LCD芯片具有对比度较低、光能利用率低、亮度较低以及分辨率较低的劣势，目前来看全彩AR产品的最优技术方案只能选择LCoS或基于DMD芯片的DLP方案。从分辨率、亮度、对比度和光能利用率上来说二者不相上下，DMD芯片略优于LCoS芯片。但是由于DMD芯片为全球独供，LCoS芯片的量产供应商选择更多，所以成本上LCoS光机具有更显著的优势。
现有的LCoS光机通常将照明系统和投影系统设置在PBS棱镜的两侧，受光学焦距限制，照明、中继和投影系统存在极限长度，光机整体成直线型结构，体积难以缩减，无法满足近眼显示设备日趋小型化与轻量化的趋势，因此需要一种小尺寸、轻便的微型投射模组以满足市场需求。
发明内容
本申请的目的在于，提供一种微型投射模组与头戴显示设备，其能够满足小型化与轻量化的市场趋势。
本申请的另一个目的在于，提供一种微型投射模组与头戴显示设备，有利于提升镜头成品像质。
为达到以上目的，根据本申请的第一方面，提供一种微型投射模组，包括：
照明组件，被配置为提供一偏振照明光；
显示芯片，被配置为将所述偏振照明光调制成一偏振图像光；
投影组件，被配置为将所述偏振图像光投射成像；
中继组件，被配置为将所述偏振照明光传输至所述显示芯片，以及将所述偏振图像光传输至所述投影组件，所述中继组件包括偏振分光组件，所述偏振分光组件具有第一侧面，所述偏振图像光从所述第一侧面进入所述投影组件；
所述投影组件包括用于光路矫正的第三投影子镜头，所述第三投影子镜头与所述第一侧面相对，二者分体且间隔地设置。
根据本申请的第一方面的一实施例，所述投影组件还包括用于容置所述第三投影子镜头的镜筒，所述第三投影子镜头承靠所述镜筒并通过所述镜筒保持在预设位置。
根据本申请的第一方面的一实施例，所述第三投影子镜头与所述第一侧面之间设置用于调整光路的复合结构，所述复合结构贴附于所述第一侧面，所述复合结构朝向所述第三投影子镜头的一侧设置一玻璃板，所述玻璃板覆盖所述复合结构。
根据本申请的第一方面的一实施例，所述复合结构包括至少两层层叠设置的复合膜，所述复合膜用于补偿和偏心滤光。
根据本申请的第一方面的一实施例，至少两层所述复合膜包括层叠设置的四分之一波片以及偏振片。
根据本申请的第一方面的一实施例，所述显示芯片为一LCoS芯片。
根据本申请的第一方面的一实施例，所述显示芯片与所述照明光源被设置于所述偏振分光组件的同侧，所述偏振分光组件包括第一直角棱镜、第二直角棱镜以及偏振分光元件，所述第一直角棱镜包括与所述第一侧面、第一斜面以及第一底面，所述第二直角棱镜包括第二侧面、第二斜面以及第二底面，所述第一斜面与所述第二斜面相对设置，所述偏振分光元件设置在所述第一斜面与所述第二斜面之间，所述偏振分光元件用于反射具有第一偏振状态的偏振光并透射具有第二偏振状态的偏振光，所述第二侧面与所述照明组件相对，以接收来自所述照明组件的偏振照明光。
根据本申请的第一方面的一实施例，所述中继组件包括至少一第一投影子镜头以及至少一第二投影子镜头，所述至少一第一投影子镜头被设置于所述偏振分光组件与所述显示芯片之间的光路中，被配置为为所述偏振照明光与所述偏振图像光提供一传输通路并进行光路校正；所述至少一第一投影子镜头与所述至少一第二投影子镜头被设置于所述偏振分光组件的不同侧，被配置为对光路实现至少两次的校正，其中，所述至少一第二投影子镜头被配置为可同时实现光路校正与反射的功能；所述至少一第一投影子镜头与所述至少一第二投影子镜头与所述第三投影子镜头共同满足光学系统的投影要求。
根据本申请的第一方面的一实施例，所述照明组件包括：照明光源，所述照明光源被配置为发射多路单色照明光；准直器件；合色器件；起偏器件；以及反射器件；其中所述准直器件与所述合色器件被设置于所述照明光源和所述起偏器件之间的光路中，被配置为将所述多路单色照明光准直合成一路合色照明光，所述起偏器件被配置为将所述合色照明光起偏成所述偏振照明光，所述反射器件被设置于所述起偏器件和所述中继组件之间的光路中，被配置为以全反射的方式将所述偏振照明光传输至所述中继组件。
根据本申请的第二方面，提供了一种头戴显示设备，其包括至少一个所述的微型投影模组；以及， 至少一光波导。
为达到以上目的，根据本申请的另一方面，提供一种微型投射模组，包括：
照明组件，被配置为提供一偏振照明光；
显示芯片，被配置为将所述偏振照明光调制成一偏振图像光；
投影组件，被配置为将所述偏振图像光投射成像；
中继组件，被配置为将所述偏振照明光传输至所述显示芯片，以及将所述偏振图像光传输至所述投影组件，所述中继组件包括偏振分光组件以及至少一第二投影子镜头，所述偏振分光组件具有第一底面，所述偏振图像光适于通过所述第一底面达到所述第二投影子镜头，所述至少一第二投影子镜头被配置为可同时实现光路校正与反射的功能，所述中继组件还包括设置在所述第一底面与所述第二投影子镜头之间的相位延迟器；
所述第二投影子镜头的折射率与所述相位延迟器折射率的差异百分比不超过30％，
和/或，所述第二投影子镜头与所述相位延迟器通过光学胶连接，所述第二投影子镜头的折射率与所述光学胶的折射率的差异百分比不超过30％。
根据本申请的第一方面的一实施例，所述第二投影子镜头的折射率与所述相位延迟器折射率的差异百分比不超过10％，和/或，所述第二投影子镜头的折射率与所述光学胶的折射率的差异百分比不超过10％。
根据本申请的第一方面的一实施例，所述第二投影子镜头的折射率与所述相位延迟器折射率的差异百分比不超过1％，和/或，所述第二投影子镜头的折射率与所述光学胶的折射率的差异百分比不超过1％。
根据本申请的第一方面的一实施例，所述相位延迟器贴附于所述第一底面。
根据本申请的第一方面的一实施例，所述第二投影子镜头包括一远离所述偏振分光组件的第二子镜头光学面，所述第二子镜头光学面为一反射面。
根据本申请的第一方面的一实施例，所述相位延迟器为四分之一波片。
根据本申请的第一方面的一实施例，所述显示芯片与所述照明光源被设置于所述偏振分光组件的同侧，所述偏振分光组件包括第一直角棱镜、第二直角棱镜以及偏振分光元件，所述第一直角棱镜包括与所述第一侧面、第一斜面以及第一底面，所述第二直角棱镜包括第二侧面、第二斜面以及第二底面，所述第一斜面与所述第二斜面相对设置，所述偏振分光元件设置在所述第一斜面与所述第二斜面之间，所述偏振分光元件用于反射具有第一偏振状态的偏振光并透射具有第二偏振状态的偏振光，所述第二侧面与所述照明组件相对，以接收来自所述照明组件的偏振照明光。
根据本申请的第一方面的一实施例，所述中继组件包括至少一第一投影子镜头以及至少一所述第二投影子镜头，所述至少一第一投影子镜头被设置于所述偏振分光组件与所述显示芯片之间的光路中，被配置为为所述偏振照明光与所述偏振图像光提供一传输通路并进行光路校正；所述至少一第一投影子镜头与所述至少一第二投影子镜头被设置于所述偏振分光组件的不同侧，被配置为对光路实现至少两次的校正，其中，所述至少一第二投影子镜头被配置为可同时实现光路校正与反射的功能；所述至少一第一投影子镜 头与所述至少一第二投影子镜头与所述至少一第三投影子镜头共同满足光学系统的投影要求。
根据本申请的第一方面的一实施例，所述显示芯片为一LCoS芯片。
根据本申请的另一方面，提供了一种头戴显示设备，其包括至少一个所述的微型投影模组；以及，至少一光波导。
附图说明
图1是根据本发明的一些实施例的微型投射模组光学系统的立体结构示意图；
图2A是根据本发明的一些实施例的微型投射模组光学系统的平面主视图；
图2B是图2A中虚线框内部分的平面右视图；
图3是根据本发明的一些变形实施例的微型投射模组光学系统的平面主视图；
图4是根据本发明的另一些变形实施例的微型投射模组光学系统的平面主视图；
图5是根据本发明的又一些变形实施例的微型投射模组光学系统的平面主视图；
图6是根据本发明的一些实施例的微型投射模组的3D结构图；
图7A-图7C是根据本发明的一些实施例的AR眼镜的立体结构示意图。
具体实施方式
下面参照具体实施例，对本发明的构思进一步详细说明。需要指出，这里列举的实施例仅仅用于清楚地阐述本发明的发明构思，而不应理解成对本发明的限制。在此涉及的微型投射模组以及头戴显示设备的技术特征，只要没有违背自然规律或者技术规范，都可以在本发明构思的框架内任意组合或者替换，都在本发明的构思范围内。
需要指出，附图示出的实施例仅作为示例用于具体和形象地解释和说明本发明的构思，其在尺寸结构方面既不必然按照比例绘制，也不构成对本发明构思的限制。
在本说明书中提到或者可能提到的上、下、左、右、前、后、正面、背面、顶部、底部、竖直、水平等方位用语是相对于各个附图中所示的构造或者产品正常使用状态所进行定义的，它们是相对的概念，因此有可能会根据其所处不同位置、不同使用状态而进行相应地变化。所以，也不应当将这些或者其他的方位用语解释为限制性用语。
图1是根据本发明一实施例的一种微型投射模组光学系统的立体结构示意图，该微型投射模组包括一照明组件10、一中继组件20、一显示芯片30以及一投影组件40。该照明组件10用于提供具有同一偏振状态的偏振照明光。该中继组件20用于将来自照明组件10的至少一部分偏振照明光传输至显示芯片30。该显示芯片30用于将该偏振照明光调制成带有图像信息的偏振图像光，并再次通过中继组件20将该偏振图像光传输至投影组件40。该投影组件40用于将调制后的偏振图像光投射成像，至头戴显示设备的其他光学部件，如光波导。即整个光学系统中，中继系统有部分光路为照明系统和投影系统所复用。
如图1所示，R代表红光，G代表绿光，B代表蓝光，W代表白光。为了区分偏振照明光和偏振图像光，本申请中的偏振照明光用S偏振光/P偏振光表示，偏振图像光用S’偏振光/P’偏振光表示。图中实线代表照明光路，虚线代表投影光路，相对应的，照明光路与其所经过的光学元件构成照明系统，投影光路与其所经过的光学元件构成投影系统，下文不再赘述。
具体地，如图2A-2B所示，图2A为该微型投射模组光学系统的平面主视图，图2B为图2A中虚线框内部分的平面右视图。照明组件10包括一照明光源11、一准直器件12、一合色器件13、一匀光器件14、一第一中继透镜15、一起偏器件16与一反射器件17。
照明光源11进一步包括一第一光源111与一第二光源112，优选的，第一光源111可以是一绿色LED，第二光源112可以是一红色与蓝色的二合一LED。可以理解的是，照明光源的颜色、类型、数量与组合方式也可以有其他情况，在本发明中不做限制。
准直器件12进一步包括一第一准直透镜组121与一第二准直透镜组122，该第一准直透镜组121和该第二准直透镜122组各自均包括至少一光学镜片，优选为一球面镜与一柱面镜组成的光学镜片组，也可以是球面镜、柱面镜、非球面镜中的两相同类型的镜片组成的光学镜片组或其中两种类型镜片的任意组合，也就是说，组成准直透镜组的光学镜片面型在本申请中不受限制。合色器件13进一步包括一第一选择性反射膜131，一第二选择性反射膜132以及一楔形棱镜133。第一准直透镜组121用于将第一光源111发出的光线进行收束、准直并传输至该第一选择性反射膜131，第二准直透镜组122用于将第二光源112发出的光线进行收束、准直并传输至该第二选择性反射膜132。
在本可选实施例中，第一选择性反射膜131用于反射蓝光并透射绿光，第二选择性反射膜132用于反射红光并透射绿光、蓝光。该第一选择性反射膜131被设置于楔形棱镜133的下表面，与第一光源111相对，该第二选择性反射膜132被设置于楔形棱镜133的上表面，与第二光源112相对。第一光源111出射的绿光经第一准直透镜组121准直后依次通过第一选择性反射膜131、楔形棱镜133和第二选择性反射膜132；第二光源112出射的红光经第二准直透镜组122准直后被第二选择性反射膜132反射；第二光源112出射的蓝光经第二准直透镜组122准直后依次通过第二选择性反射膜132和楔形棱镜133，被第一选择性反射膜131反射，再次通过楔形棱镜133和第二选择性反射膜132之后，与前述的红光、绿光合成一束白光，通过匀光器件14，成为一均匀照明光。上述选择性反射膜的材质和透反比例等性质均针对照明光源的具体颜色与类型进行选择，并不局限于以上所描述的选择性透反性质。匀光器件14可以是一复眼透镜或其他常用匀光元件，用于获得均匀的照明分布。
通过匀光器件14后获得的该均匀照明光经第一中继透镜15传输后，通过起偏器件16，成为具有第一偏振状态的偏振照明光。该起偏器件16可以是一第一偏振片，被配置为仅通过具有第一偏振状态的偏振光，并阻挡具有第二偏振状态的偏振光。起偏器件16也可以是一第一偏振复用元件，用于仅通过具有第一偏振状态的偏振光，并将具有第二偏振状态的偏振光也转化为具有第一偏振状态的偏振光。其中，具有第一偏振状态的偏振光与具有第二偏振状态的偏振光二者的偏振方向相互垂直，比如，该具有第一偏振状态的偏振光可以是线偏振光中的S光，该具有第二偏振状态的偏振光可以是线偏振光中的P光。
该起偏器件16被设置于第一中继透镜15和反射器件17之间的光路中，优选的，该起偏器件16 被实施为一S偏振片。反射器件17优选包括一全反射棱镜171，如一普罗棱镜。该全反射棱镜171包括一棱镜入射面1711，一与该棱镜入射面1711相垂直的一棱镜出射面1713，以及连接该棱镜入射面1711与该棱镜出射面1713的一棱镜反射面1712。该棱镜反射面1712为一倾斜的全内反射面，倾斜角度优选与该棱镜入射面1711为45°夹角。
起偏器件16可以直接贴附于该棱镜入射面1711。通过匀光器件14与第一中继透镜15后的该均匀照明光通过起偏器件16后转化为具有第一偏振状态的偏振照明光，在本实施例中，即S偏振光，其他自然光和杂光等被该起偏器件16阻挡无法通过。通过起偏器件16的该S偏振光垂直于该棱镜入射面1711进入全反射棱镜171内部，在棱镜反射面1712处发生全反射，并垂直于棱镜出射面1713射出，进入中继组件20。
容易理解的是，反射器件17不仅限于被实施为全反射棱镜171棱镜，也可以被实施为一平面反射镜172或其他任何具有反射性质的器件。如图3所示，该平面反射镜172包括一平面镜反射面1721，该平面镜反射面1721朝向照明光源11与中继组件20的方向倾斜布置，优选为倾斜45°角，使得来自照明光源11的光线可以被转折90°后水平进入中继组件20。值得一提的是，将反射器件17实施为全反射棱镜171相比于实施为平面反射镜172具有明显的优势，全反射棱镜171的棱镜入射面1711可以为起偏器件16和第一中继透镜15提供一安装平面和基准，使得起偏器件16可以直接贴附在棱镜入射面1711上，再将第一中继透镜15以起偏器件16为基准组装于起偏器件16的表面，有利于减小组装难度，提升组装精度。若将反射器件17实施为平面反射镜172，那么该平面反射镜172与其他光学部件之间在组装时缺少联系，组装精度将难以控制，可能会增大累计组装误差，当然在组装过程中也可根据实际情况通过其他方式进行误差补偿，反射器件17的具体实施方式与组装方法在本发明中并不做限制。
中继组件20进一步包括一第二中继透镜21，一偏振分光组件22，一第一投影子镜头23，以及一反射偏振组件24。
从照明组件10出射的具有第一偏振状态的偏振照明光，在本可选实施例中为S偏振光，经第二中继透镜21传输后进入偏振分光组件22。该偏振分光组件22进一步包括一第一直角棱镜221，一第二直角棱镜222，以及一偏振分光元件223。该第一直角棱镜221与该第二直角棱镜222均为等腰直角棱镜，该第一直角棱镜221包括一第一斜面2211，一第一侧面2212，以及一第一底面2213。该第二直角棱镜222包括一第二斜面2221，一第二侧面2222，以及一第二底面2223。该第一斜面2211与该第二斜面2221相对设置，该偏振分光元件223被设置于该第一斜面2211与该第二斜面2221之间。该偏振分光元件223可以是一偏振分光膜，此时该偏振分光组件22即为一PBS棱镜。示例性地，在组装过程中，可以在该第一斜面2211上镀偏振分光膜再将第一直角棱镜221与第二直角棱镜222的第二斜面2221胶合；也可以在该第二斜面2221上镀偏振分光膜再将第二直角棱镜222与第一直角棱镜221的第一斜面2211胶合。
组装完成后的偏振分光组件22包括一第一侧面2212，一第一底面2213，一第二侧面2222以及一第二底面2223。该第一侧面2212与该第二侧面2222相对且平行设置，该第一底面2213与该第二底面2223相对且平行设置，该第一侧面2212连接该第一底面2213与该第二底面2223，且与二者均垂直。其中，第二侧面2222用于接收来自照明组件10的偏振照明光，该偏振照明光在偏振分光元件223处反射后向下转折90°通过第二底面2223到达显示芯片30，经显示芯片30调制后变换了偏振方向的偏振图像光再次反向 通过第二底面2223，并从偏振分光元件223处透射后再通过第一底面2213向上进入反射偏振组件24，经反射偏振组件24调制后再次变换偏振方向且转折180°向下再次通过第二底面2223，此时该偏振图像光的偏振方向与首次进入偏振分光组件22的偏振照明光的偏振方向相同，在偏振分光元件223处再次反射后向左转折90°通过第一侧面2212，进入投影组件40。
该偏振分光元件223用于反射具有第一偏振状态的偏振光并透射具有第二偏振状态的偏振光，在本可选实施例中，为反射S偏振光的同时透射P偏振光。
在本可选实施例中，来自照明组件10的偏振照明光为一S偏振光，该S偏振光垂直于第二侧面2222入射，进入第二直角棱镜222中，在偏振分光元件223的表面发生反射，反射后的S偏振光垂直于第二直角棱镜222的第二底面2223出射，经过第一投影子镜头23传输后到达显示芯片30表面，被显示芯片30所接收。
该第一投影子镜头为一光路校正器件，也就是带有光路校正功能的透射式元件。所述的光路校正功能在照明系统中是指光源的整形功能，如收束，在投影系统中是指物像关系与像差的平衡功能。优选的，该第一投影子镜头23为由至少二光学镜片组成的一镜片组，第一投影子镜头23被设置于偏振分光组件22与显示芯片30之间的光路中。该第一投影子镜头23被设置于第二底面2223的外侧，且光轴与该第二底面2223垂直。第一投影子镜头23用于将从偏振分光组件22出射的S偏振光会聚并保持在特定范围内，传输至显示芯片30，即此时第一投影子镜头23中通过的光线为照明光路的一部分。
进一步的，第一投影子镜头23的光学镜片以及准直透镜组的光学镜片可进行切割(D-cut)来减小径向方向的尺寸，以避免空间干涉。
显示芯片30用于将该偏振照明光调制成带有图像信息的偏振图像光，并改变其偏振状态，示例性的，将具有第一偏振状态的偏振光转化为具有第二偏振状态的偏振光，该第一偏振状态与该第二偏振状态的偏振方向相互垂直。
该显示芯片30优选为一LCoS芯片，由于LCoS芯片的特性，入射到芯片表面的S偏振光经调制后成为带图像信息的P’偏振光。可以理解的是，由于LCoS芯片本身就是偏振光调制器件，因此不再需要增加额外的偏振光调制器件，若采用其他类型的显示芯片，对于不带偏振光调制功能的显示芯片，则需在显示芯片表面额外设置一偏振光调制器件以对偏振图像光的偏振状态进行调制。
经显示芯片30调制后带有图像信息的偏振图像光，在本可选实施例中即P’偏振光再次经过第一投影子镜头23，垂直于第二直角棱镜222的第二底面2223入射，进入第二直角棱镜222中，再在偏振分光元件223处发生透射，进入第一直角棱镜221，之后垂直于第一直角棱镜221的第一底面2213出射。可以理解的是，此时第一投影子镜头23中通过的光线为投影光路的一部分。即对整个光学系统来说，该第一投影子镜头23对照明光路和投影光路同时实现了校正功能，中继系统中有部分光路为照明系统和投影系统所复用，使该微型投射模组整体更符合小型化条件。
值得一提的是，在现有技术的直线型投射模组中，显示芯片与照明光源一般分布于偏振分光组件的不同侧，而在本申请中，显示芯片30与照明光源11分布于偏振分光组件22的同侧，且照明光路中的合色照明光(即白光)与投影光路中的投影出射光(即最终从微型投射模组中出射的成像光线)二者的光路 相互垂直。由于显示芯片与照明光源为有源器件，需要外接电路以供其运行，本申请将有源器件布置在相邻近的位置，该分布方式有利于使显示芯片与照明光源的外接电路处于相邻或相近的位置，优选的，至少一个照明光源的线路板与显示芯片的线路板处于同一平面，且一体形成。这样的方式有利于在降低电路设计的难度，简化电路分布，优化线路板结构的同时提高产品的集成度，进一步使微型投射模组小型化。
该中继组件20进一步包括一反射偏振组件24，该反射偏振组件24包括一相位延迟器241，和一第二投影子镜头242。该相位延迟器241被设置于第一直角棱镜221的第一底面2213与第二投影子镜头242之间。
该第二投影子镜头也为一光路校正器件，该第二投影子镜头242可以为一单独的光学镜片，也可以为一镜片组，可以是球面镜、非球面镜等，其面型与类型组合在本发明中不做限制。其中，第二投影子镜头242包括一远离偏振分光组件22的第二子镜头光学面2421，该第二子镜头光学面2421为一反射面。该第二投影子镜头242被设置于第一底面2213的外侧，且光轴与该第一底面2213垂直。可以理解的是，该第二投影子镜头242可以同时满足光路校正与光路反射的多种功能，且该第二投影子镜头242与显示芯片30分别被设置于偏振分光组件22的不相邻的两侧。
该相位延迟器241优选被实施为一四分之一波片。在组装过程中，该相位延迟器241可以被直接贴附于第一直角棱镜221的第一底面2213，再将第二投影子镜头242设置于相位延迟器241的表面，以减小安装难度。
在本申请的一个实施例中，该相位延迟器241被设置于第一直角棱镜221的第一底面2213与第二投影子镜头242之间，即相位延迟器241分别连接第一直角棱镜221的第一底面2213与第二投影子镜头242。在本申请一具体示例中，该相位延迟器241可以被直接贴附于第一直角棱镜221的第一底面2213，再通过胶合的方式将第二投影子镜头242固定于相位延迟器241的表面。其中，第二投影子镜头242采用与相位延迟器241折射率近似的材料，和/或，第二投影子镜头242采用与胶合光学胶折射率近似材料，以减小经相位延迟器241后在相位延迟器241和第一直角棱镜221的第一底面2213的已转向偏振反射光，减少此反射光未经第二投影子镜头242直接出射带来的非成像杂光，提升对比度。
具体地，第二投影子镜头242的折射率与相位延迟器241折射率的差异百分比不超过30％。也即，(第二投影子镜头242的折射率-相位延迟器241的折射率)/第二投影子镜头242的折射率≤30％。优选地，该差异百分比不超过20％，或10％，或5％，或1％。
具体地，第二投影子镜头242的折射率与用于胶合第二投影子镜头242和相位延迟器241的光学胶的折射率的差异百分比不超过30％。也即，(第二投影子镜头242的折射率-光学胶的折射率)/第二投影子镜头242的折射率≤30％。优选地，该差异百分比不超过20％，或10％，或5％，或1％。
从第一直角棱镜221的第一底面2213出射的P’偏振光经过相位延迟器241，转为圆偏振光，经过第二投影子镜头242的传输后被第二子镜头光学面2421反射，再次通过相位延迟器241，偏振方向改变90°，即具有第二偏振状态的偏振光转变为具有第一偏振状态的偏振光，在本可选实施例中对应为P’偏振光变为S’偏振光。
该S’偏振光垂直于第一直角棱镜221的第一底面2213入射第一直角棱镜221，在偏振分光元件 223处发生反射，垂直于第一直角棱镜221的第一侧面2212出射，经过投影组件40投射成像，至头戴显示设备的其他光学部件，如光波导。
投影组件40包括至少一第三投影子镜头41，可以理解的是，该第三投影子镜头41也为一光路校正器件。该第三投影子镜头41包括至少一光学镜片。第三投影子镜头41设置于第一侧面2212的外侧，且光轴与该第一侧面2212垂直。
值得一提的是，第一投影子镜头23、第二投影子镜头242与第三投影子镜头41中的任何一个均不能单独满足该微型投射模组的投影系统光学要求，该第一投影子镜头23、第二投影子镜头242与第三投影子镜头41对光路的共同校正使投影光路满足系统整体的有效焦距要求。可以理解的是，其中，第一投影子镜头23既要配合第二投影子镜头242与第三投影子镜头41满足投影系统的光学参数需求，还要满足照明系统的光学参数需求，使第一投影子镜头23内部的光路为照明系统和投影系统所复用。
如图2A至图5所示，在本申请的一个实施例中，第三投影子镜头41与第一直角棱镜221为分体式结构，即第三投影子镜头41被间隔地设置于第一直角棱镜221的第一侧面2212的外侧。在本申请中，第三投影子镜头41与第一直角棱镜221的第一侧面2212之间具有一定间隙，避免了第三投影子镜头41通过胶合等方式直接固定于第一直角棱镜221的第一侧面2212。
应可以理解，若采用胶合的方式将第三投影子镜头41直接固定于第一直角棱镜221的第一侧面2212，光学胶被设置于第三投影子镜头41和第一侧面2212之间，由于光学胶的特性，一方面会使得第三投影子镜头41与第一直角棱镜221之间存在一定的组装公差，另一方面由于胶水的厚度不均会造成第三投影子镜头41偏心，再一方面还会有第三投影子镜头41倾斜的问题产生。进一步地，棱镜的组装公差也会使得第三投影子镜头41产生连带偏心和倾斜的问题。
为解决上述问题，在本申请中，第三投影子镜头41与第一直角棱镜221设置为分体式结构，即第三投影子镜头41与第一直角棱镜221之间间接地固定。例如，在本申请一具体示例中，第三投影子镜头41被容置于一镜筒内，第三投影子镜头41通过一镜筒承靠和定位于第一直角棱镜221的第一侧面2212。相对于第三投影子镜头41直接胶合固定于第一直角棱镜221产生的组装公差，本申请的这种分体式结构，可以弱化胶合过程中组装公差的问题，使其仅有镜筒本身的组装公差，提高了组装精度。进一步地，第三投影子镜头41和镜筒的是适配度高于第三投影子镜头41和第一直角棱镜221的适配度，在组装过程中可以减小第三投影子镜头41倾斜和偏心的影响，进而提升镜头成品像质和良率，减少胶合的时间和费用成本。在本申请中，适配度是指在组装过程中的松紧配合程度。
在本申请的一个实施例中，第三投影子镜头41与第一直角棱镜221之间设置一复合结构，复合结构包括至少两层沿水平方向堆叠设置的复合膜。在本申请一具体示例中，复合结构被贴附于第一直角棱镜221的第一侧面2212上，与第三投影子镜头41沿水平方向相对设置。进一步地，复合结构朝向第三投影子镜头41的一侧设置一玻璃板，即玻璃板叠设于复合结构以将复合结构覆盖。玻璃板可以使得复合结构的面型一致，保证成像质量，提升良率的同时可以减小反射，进而提升微型投射模组的对比度。
在本申请一具体示例中，复合膜可以被实施为四分之一波片和偏振片，或其他形式的补偿和偏心滤光作用的复合膜。
如图1所示，从合色器件13出射的合色照明光沿第一方向通过起偏器件16转变为偏振照明光S，该偏振照明光S通过反射器件17后转折90°沿第二方向进入偏振分光组件22，在偏振分光组件22中再次转折90°沿第三方向到达显示芯片30，经显示芯片30调制为偏振图像光P’折返180°沿第四方向再次到达偏振分光组件22，发生透射后进入反射偏振组件24，经反射偏振组件24调制为偏振图像光S’折返180°沿第五方向第三次进入偏振分光组件22，在其中发生反射后该偏振图像光S’转折90°沿第六方向进入投影组件40，最终经投影组件40调制成投影出射光从微型投射模组投出，形成完整的照明光路与投影光路，其中，第一方向与第三方向相互平行且反向，第一方向与第六方向相互垂直。
可以理解的是，在本可选实施例中，完整的投影镜头由三个投影子镜头共同组成，至少有一个投影子镜头被设置于偏振分光组件22与显示芯片30之间，其他投影子镜头被设置于偏振分光组件22除朝向显示芯片30的光学面外的其他光学面的外侧，相比于将完整的投影镜头布置于偏振分光组件同一侧的方案，大大减小了光机整体长度方向的尺寸。其中，第一投影子镜头23既用于照明光路，对光线进行收束，又用于投影光路，在满足物像关系和像质平衡的同时，降低PBS棱镜尺寸需求，有效利用了光机内部空间，在满足总光程要求的前提下将光路进行了折叠，减小了整体体积；第二投影子镜头242将满足物像关系需求的光程进行反射折叠，缩短了折叠光路一半的长度，进一步减小了体积；第三投影子镜头41用于平衡像质并扩展光线，使得芯片目标图像无损失地投射出光机，即该第一投影子镜头23、第二投影子镜头242以及第三投影子镜头41共同满足光学系统的投影要求，完成投影。本申请提供的微型投射模组相比于传统微型投射模组4cc～6cc的体积大小，可以将体积控制在2cc左右，具有明显的小型化优势。
在另一个实施例中，如图4所示，与可选实施例相比，其中第二投影子镜头242可以被一反射镜242A替换。该反射镜242A包括一反射表面2421A，该反射镜242A仅用于将光路折返180°，对光线不具有其他调制功能。在这一实施例中，完整的投影镜头由两个投影子镜头共同组成，即第一投影子镜头23A与第三投影子镜头41A。该第一投影子镜头23A被设置于偏振分光组件22与显示芯片30之间，该第三投影子镜头41A被设置于偏振分光组件22的另一侧。第一投影子镜头23A与第三投影子镜头41A共同组成完整的投影系统，满足整体的有效焦距要求，可以理解的是，其中，第一投影子镜头23A既要配合第三投影子镜头41A满足投影系统的光学参数需求，还要满足照明系统的光学参数需求，使部分光路为照明系统和投影系统所复用。
值得一提的是，在本申请中，投影子镜头的数量和设置位置并不为本发明所限制，根据投影系统和照明系统的光学设计要求将投影镜头拆分为不同数量的投影子镜头并设置在不同的位置为本领域技术人员容易想到的。
在又一个实施例中，如图5所示，与可选实施例相比，其中投影组件40B进一步包括一光路转折元件42B。该光路转折元件42B优选为一等腰直角棱镜，其斜面为一全内反射面，用于将光路转折90°。使得从第三投影子镜头41B中投射出的图像光转折90°后再进入头戴显示设备的其他光学部件，如光波导。光路转折元件的设置方向可以根据实际需求而定，使得光路向上、向下或向垂直纸面向内、向外的方向进行转折，增大光机设置方式的灵活程度，光路转折元件的设置方向在此不做限制。
除了上述微型投射模组光学系统，该微型投射模组还进一步包括一供电单元，一外壳，各光学元件之间的结构连接件，以及散热单元等，如图6所示，为所述微型投射模组的3D结构图。
本发明还提出一种头戴显示设备，所述头戴显示设备包括至少一如前所述的微型投射模组，至少一镜片单元，一用于安装镜片单元和微型投射模组的框架，用于佩戴的镜腿，以及用于处理数据和图像信息的计算单元，其中微型投射模组根据计算单元发出的指令输出图像。下面以AR眼镜为例，对包括所述微型投射模组的头戴显示设备进行示例性的详细说明。
如图7A-图7C所示，AR眼镜包括微型投射模组1，用于安装镜片单元的镜框2，左镜片单元3，右镜片单元4，计算单元5，用于佩戴的镜腿6。在此，左镜片单元3与右镜片单元4固定安装于镜框2内，镜腿6可以以任意方式与镜框2连接，例如以柔性的方式，或者以折页的形式，或者以固定的方式，又或者以可拆卸的方式，从而形成AR眼镜的主体部分。AR眼镜的电子元器件可以选择性地安装在镜腿6和/或镜框2上，或者嵌入/埋入其材料中。所述电子元器件包括但不限于用于处理数据和图像信息的计算单元5、眼球追踪器、深度传感器、空间传感器、位置传感器及它们的组合等。
在图7A示出的实施例中，优选的，左镜片单元3与右镜片单元4为一整体光波导的共同组成部分，即左镜片单元3与右镜片单元4在鼻托上方位置具有一连续的区域，并且耦入区域设置在该连续的区域，所述耦入区域用于将光线向左镜片单元3与右镜片单元4的方向同时进行传播。微型投射模组1的数量为一，安装于镜框2中部的鼻托位置附近，其出光区域对应于光波导的耦入区域设置，微型投射模组投射出的经调制后的适于被左右眼同时接收的图像光作为耦入光线耦入光波导，经转折、扩瞳后从耦出区域耦出，最终被用户眼睛接收，即单光机配单光波导，从中间向两侧同时传输耦出图像光。
在图7B示出的实施例中，左镜片单元3与右镜片单元4为各自独立的二光波导，左镜片单元3的右上角与右镜片单元4的左上角位置各自具有一耦入区域，所述耦入区域用于将光线各自向左镜片单元3与右镜片单元4的方向进行传播。微型投射模组1的数量为二，安装于镜框2中部的鼻托位置附近，两个微型投射模组的出光区域与左右镜片单元的耦入区域各自对应设置，左右两个微型投射模组各自投射出适于被左眼接收的图像光与适于被右眼接收的图像光，经调制后的图像光作为耦入光线耦入光波导，经转折、扩瞳后从耦出区域耦出，最终被用户眼睛接收，即双光机配双光波导，从角落向中心传输耦出图像光。
在图7C示出的实施例中，左镜片单元3与右镜片单元4为各自独立的二光波导，左镜片单元3的左侧中部与右镜片单元4的右侧中部位置各自具有一耦入区域，所述耦入区域用于将光线各自向左镜片单元3与右镜片单元4的方向进行传播。微型投射模组1的数量为二，安装于镜腿6靠近镜框2的位置，两个微型投射模组的出光区域与左右镜片单元的耦入区域各自对应设置，左右两个微型投射模组各自投射出适于被左眼接收的图像光与适于被右眼接收的图像光，经调制后的图像光作为耦入光线耦入光波导，经转折、扩瞳后从耦出区域耦出，最终被用户眼睛接收，即双光机配双光波导，从边缘向中心传输耦出图像光。
类似地，结合头戴显示设备的具体外形和空间结构，也可以考虑其他镜片单元的形状，耦入区域的设置位置，以及微型投射模组的设置位置等，本发明对此不做任何限制。
需要指出，在此提出的技术方案不仅仅局限于上述说明中的内容，本领域技术人员可以在不脱离本发明的发明思想的前提下，对上述实施例进行多种变型和修改，而这些变型和修改均属于本发明的保护范围。

Claims (20)

  1. 一种微型投射模组，其特征在于，包括：
    照明组件，被配置为提供一偏振照明光；
    显示芯片，被配置为将所述偏振照明光调制成一偏振图像光；
    投影组件，被配置为将所述偏振图像光投射成像；
    中继组件，被配置为将所述偏振照明光传输至所述显示芯片，以及将所述偏振图像光传输至所述投影组件，所述中继组件包括偏振分光组件，所述偏振分光组件具有第一侧面，所述偏振图像光从所述第一侧面进入所述投影组件；
    所述投影组件包括用于光路矫正的第三投影子镜头，所述第三投影子镜头与所述第一侧面相对，二者分体且间隔地设置。
  2. 根据权利要求1所述的微型投射模组，其特征在于，所述投影组件还包括用于容置所述第三投影子镜头的镜筒，所述第三投影子镜头承靠所述镜筒并通过所述镜筒保持在预设位置。
  3. 根据权利要求1所述的微型投射模组，其特征在于，所述第三投影子镜头与所述第一侧面之间设置用于调整光路的复合结构，所述复合结构贴附于所述第一侧面，所述复合结构朝向所述第三投影子镜头的一侧设置一玻璃板，所述玻璃板覆盖所述复合结构。
  4. 根据权利要求3所述的微型投射模组，其特征在于，所述复合结构包括至少两层层叠设置的复合膜，所述复合膜用于补偿和偏心滤光。
  5. 根据权利要求4所述的微型投射模组，其特征在于，至少两层所述复合膜包括层叠设置的四分之一波片以及偏振片。
  6. 根据权利要求1所述的所述的微型投射模组，其中，所述显示芯片为一LCoS芯片。
  7. 根据权利要求1-6任一所述的微型投射模组，其特征在于，所述显示芯片与所述照明光源被设置于所述偏振分光组件的同侧，所述偏振分光组件包括第一直角棱镜、第二直角棱镜以及偏振分光元件，所述第一直角棱镜包括与所述第一侧面、第一斜面以及第一底面，所述第二直角棱镜包括第二侧面、第二斜面以及第二底面，所述第一斜面与所述第二斜面相对设置，所述偏振分光元件设置在所述第一斜面与所述第二斜面之间，所述偏振分光元件用于反射具有第一偏振状态的偏振光并透射具有第二偏振状态的偏振光，所述第二侧面与所述照明组件相对，以接收来自所述照明组件的偏振照明光。
  8. 根据权利要求7所述的微型投射模组，其特征在于，所述中继组件包括至少一第一投影子镜头以及至少一第二投影子镜头，所述至少一第一投影子镜头被设置于所述偏振分光组件与所述显示芯片之间的光路中，被配置为为所述偏振照明光与所述偏振图像光提供一传输通路并进行光路校正；所述至少一第一投影子镜头与所述至少一第二投影子镜头被设置于所述偏振分光组件的不同侧，被配置为对光路实现至少两次的校正，其中，所述至少一第二投影子镜头被配置为可同时实现光路校正与反射的功能；所述至少一第一投影子镜头与所述至少一第二投影子镜头与所述第三投影子镜头共同满足光学系统的投影要求。
  9. 根据权利要求1-6任一所述的微型投射模组，其特征在于，所述照明组件包括：照明光源，所述照明光源被配置为发射多路单色照明光；准直器件；合色器件；起偏器件；以 及反射器件；其中所述准直器件与所述合色器件被设置于所述照明光源和所述起偏器件之间的光路中，被配置为将所述多路单色照明光准直合成一路合色照明光，所述起偏器件被配置为将所述合色照明光起偏成所述偏振照明光，所述反射器件被设置于所述起偏器件和所述中继组件之间的光路中，被配置为以全反射的方式将所述偏振照明光传输至所述中继组件。
  10. 一种头戴显示设备，其特征在于，包括：
    至少一个根据权利要求1到9中任一项所述的微型投影模组；以及，
    至少一光波导。
  11. 一种微型投射模组，其特征在于，包括：
    照明组件，被配置为提供一偏振照明光；
    显示芯片，被配置为将所述偏振照明光调制成一偏振图像光；
    投影组件，被配置为将所述偏振图像光投射成像；
    中继组件，被配置为将所述偏振照明光传输至所述显示芯片，以及将所述偏振图像光传输至所述投影组件，所述中继组件包括偏振分光组件以及第二投影子镜头，所述偏振分光组件具有第一底面，所述偏振图像光适于通过所述第一底面达到所述第二投影子镜头，所述第二投影子镜头被配置为可同时实现光路校正与反射的功能，所述中继组件还包括设置在所述第一底面与所述第二投影子镜头之间的相位延迟器；
    所述第二投影子镜头的折射率与所述相位延迟器折射率的差异百分比不超过30％，
    和/或，所述第二投影子镜头与所述相位延迟器通过光学胶连接，所述第二投影子镜头的折射率与所述光学胶的折射率的差异百分比不超过30％。
  12. 根据权利要求11所述的微型投射模组，其特征在于，所述第二投影子镜头的折射率与所述相位延迟器折射率的差异百分比不超过10％，和/或，所述第二投影子镜头的折射率与所述光学胶的折射率的差异百分比不超过10％。
  13. 根据权利要求11所述的微型投射模组，其特征在于，所述第二投影子镜头的折射率与所述相位延迟器折射率的差异百分比不超过1％，和/或，所述第二投影子镜头的折射率与所述光学胶的折射率的差异百分比不超过1％。
  14. 根据权利要求11所述的微型投射模组，其特征在于，所述相位延迟器贴附于所述第一底面。
  15. 根据权利要求11-14任一所述的微信投射模组，其特征在于，所述第二投影子镜头包括一远离所述偏振分光组件的第二子镜头光学面，所述第二子镜头光学面为一反射面。
  16. 根据权利要求11-14任一所述的微信投射模组，其特征在于，所述相位延迟器为四分之一波片。
  17. 根据权利要求11-14任一所述的微信投射模组，其特征在于，所述显示芯片与所述照明光源被设置于所述偏振分光组件的同侧，所述偏振分光组件包括第一直角棱镜、第二直角棱镜以及偏振分光元件，所述第一直角棱镜包括与所述第一侧面、第一斜面以及第一底面，所述第二直角棱镜包括第二侧面、第二斜面以及第二底面，所述第一斜面与所述第二斜面相对设置，所述偏振分光元件设置在所述第一斜面与所述第二斜面之间，所述偏振分光元 件用于反射具有第一偏振状态的偏振光并透射具有第二偏振状态的偏振光，所述第二侧面与所述照明组件相对，以接收来自所述照明组件的偏振照明光。
  18. 根据权利要求11-14任一所述的微信投射模组，其特征在于，所述中继组件包括至少一第一投影子镜头以及至少一所述第二投影子镜头，所述至少一第一投影子镜头被设置于所述偏振分光组件与所述显示芯片之间的光路中，被配置为为所述偏振照明光与所述偏振图像光提供一传输通路并进行光路校正；所述至少一第一投影子镜头与所述至少一第二投影子镜头被设置于所述偏振分光组件的不同侧，被配置为对光路实现至少两次的校正，其中，所述至少一第二投影子镜头被配置为可同时实现光路校正与反射的功能；所述至少一第一投影子镜头与所述至少一第二投影子镜头与所述至少一第三投影子镜头共同满足光学系统的投影要求。
  19. 根据权利要求11-14任一所述的微信投射模组，其特征在于，所述显示芯片为一LCoS芯片。
  20. 一种头戴显示设备，其特征在于，包括：
    至少一个根据权利要求11到19中任一项所述的微型投影模组；以及，
    至少一光波导。
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002107819A (ja) * 2000-09-29 2002-04-10 Hitachi Ltd 映像表示装置及び駆動回路
US20120170000A1 (en) * 2009-09-11 2012-07-05 Masayuki Imaoka Projection Optical System and Image Projecting Device
CN112987473A (zh) * 2021-04-13 2021-06-18 杭州灵伴科技有限公司 一种微型投影显示装置以及具有它的ar显示系统
CN113009759A (zh) * 2021-05-10 2021-06-22 杭州灵伴科技有限公司 一种微型投影显示装置及ar显示系统
CN214795441U (zh) * 2021-04-30 2021-11-19 舜宇光学（浙江）研究院有限公司 微型投影光引擎和穿戴式显示设备

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002107819A (ja) * 2000-09-29 2002-04-10 Hitachi Ltd 映像表示装置及び駆動回路
US20120170000A1 (en) * 2009-09-11 2012-07-05 Masayuki Imaoka Projection Optical System and Image Projecting Device
CN112987473A (zh) * 2021-04-13 2021-06-18 杭州灵伴科技有限公司 一种微型投影显示装置以及具有它的ar显示系统
CN214795441U (zh) * 2021-04-30 2021-11-19 舜宇光学（浙江）研究院有限公司 微型投影光引擎和穿戴式显示设备
CN113009759A (zh) * 2021-05-10 2021-06-22 杭州灵伴科技有限公司 一种微型投影显示装置及ar显示系统

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