WO2021253385A1 - 一种光学器件、显示设备及其输出光和显示图像的方法 - Google Patents

一种光学器件、显示设备及其输出光和显示图像的方法 Download PDF

Info

Publication number
WO2021253385A1
WO2021253385A1 PCT/CN2020/097051 CN2020097051W WO2021253385A1 WO 2021253385 A1 WO2021253385 A1 WO 2021253385A1 CN 2020097051 W CN2020097051 W CN 2020097051W WO 2021253385 A1 WO2021253385 A1 WO 2021253385A1
Authority
WO
WIPO (PCT)
Prior art keywords
light
unit
pupil
output
optical device
Prior art date
Application number
PCT/CN2020/097051
Other languages
English (en)
French (fr)
Inventor
利沃拉·塔帕尼·卡列沃
蒋厚强
朱以胜
Original Assignee
深圳市光舟半导体技术有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 深圳市光舟半导体技术有限公司 filed Critical 深圳市光舟半导体技术有限公司
Priority to PCT/CN2020/097051 priority Critical patent/WO2021253385A1/zh
Priority to KR1020237002365A priority patent/KR20230025022A/ko
Priority to EP20941252.7A priority patent/EP4170412A4/en
Publication of WO2021253385A1 publication Critical patent/WO2021253385A1/zh

Links

Images

Classifications

    • 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
    • G02B27/0101—Head-up displays 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
    • G02B27/0081—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 with means for altering, e.g. enlarging, the entrance or exit pupil
    • 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
    • G02B5/00—Optical elements other than lenses
    • G02B5/18—Diffraction gratings
    • G02B5/1814—Diffraction gratings structurally combined with one or more further optical elements, e.g. lenses, mirrors, prisms or other diffraction gratings
    • G02B5/1819—Plural gratings positioned on the same surface, e.g. array of gratings
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
    • G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
    • G02B6/122—Basic optical elements, e.g. light-guiding paths
    • G02B6/124—Geodesic lenses or integrated gratings
    • 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
    • G02B27/0101—Head-up displays characterised by optical features
    • G02B2027/0118—Head-up displays characterised by optical features comprising devices for improving the contrast of the display / brillance control visibility
    • 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
    • G02B27/0101—Head-up displays characterised by optical features
    • G02B2027/0123—Head-up displays characterised by optical features comprising devices increasing the field of view
    • G02B2027/0125—Field-of-view increase by wavefront division

Definitions

  • the present invention relates to the technical field of optical devices, in particular to an optical device, a display device and a method for outputting light and displaying images.
  • the pupil expansion device 1 includes a waveguide plate 101, which in turn includes a diffractive entrance pupil unit 102, a diffractive pupil expansion unit 103 and a diffractive exit pupil unit 104.
  • An input beam IN1 is expanded by multiple diffraction in the pupil expanding device 1, and finally the output beam OUT1 is output.
  • the pupil coupling unit 102 diffracts the input light IN1 into the first transmitted light B1 through diffraction.
  • the first guided light B1 is diffracted by the pupil dilation unit 103 to form the expanded guided light B3.
  • the diffused guided light B3 is diffracted and output as light OUT1 by the diffractive pupil unit 104.
  • the pupil expanding device 1 can expand the light beam in two directions, the direction SX and the direction SY.
  • the width of the output beam OUT1 is much larger than the width of the input beam IN1.
  • the pupil dilation device 1 can be used to expand the visual pupil of the virtual display device, so that the eye 105 has a larger comfortable observation position (large eyebox) relative to the observation position of the virtual display device.
  • the eyes 105 of the observer can see the completed virtual image in the observation position of the output beam.
  • the output light may include one or more output light beams, where each output light beam may correspond to a different image position of the displayed virtual image.
  • the pupil expansion device may also be called, for example, an expansion device, an expansion device, and the like.
  • the intensity of the guided light (B1, B3) propagating in the waveguide plate 101 decreases as the length of its propagation path in the pupil dilation device 103 increases.
  • the guided light has undergone very many independent diffractions in the pupil dilation unit 103, and the number of diffractions is proportional to the distance of propagation. Since the light path from the entrance pupil unit 102 to the corner area 6 is long, the output intensity of the farthest (leftmost) corner area 6 may be low. Moreover, the pupil dilation unit 103 will further reduce the light intensity.
  • the intensity of the output light in the corner region 6 at the farthest point of the diffractive exit pupil unit 104 will be much lower than the intensity of the output light in the center 106 of the diffractive exit pupil unit 104.
  • the spatial intensity distribution of the output light of the pupil dilation device 1 in FIG. 1 may be uneven.
  • the present invention provides an optical device, a display device, and a method for outputting light and displaying images, so as to solve the above-mentioned background art problems.
  • an optical device including:
  • Waveguide board which includes:
  • a diffractive pupil unit which forms a first guided light and a second guided light by diffracting the input light
  • the diffractive pupil dilation unit diffracts the first guided light to form the third guided light
  • the diffractive pupil unit forms the first output light by diffracting the third guided light
  • a bypass unit which forms the fourth guided light by diffracting the second guided light
  • the first guided light propagates in the first direction
  • the second guided light propagates in the second direction
  • the angle between the first direction and the second direction is in the range of 60° to 120°
  • the diffractive pupil unit includes one or more enhanced regions to form auxiliary output light by diffracting the fourth guided light.
  • the diffractive pupil unit includes one or more of the regions, and the regions do not diffract the fourth guided light from the waveguide plate.
  • the propagation direction of the third conducted light is in the third direction and is substantially parallel to the second direction; wherein the propagation direction of the fourth conducted light is in the fourth direction, and is substantially parallel to the The first direction.
  • the first enhanced region forms the first output light by diffracting the third light guide, and at the same time diffracts the fourth light guide to form the auxiliary output light, and combines the auxiliary output light with the first output light. The light is superimposed to form a combined output light.
  • the distance between the entrance pupil unit and the bypass unit is within the range of 50% to 80% of the height of the output coupling area;
  • the pupil units do not interact with the diffractive exit pupil unit.
  • the output diffracted exit pupil unit includes one or more reference areas, which do not diffract the fourth light guide from the waveguide plate, wherein the total area of the reference area is 30% of the area of the exit pupil unit To 95%.
  • At least a part of the fourth conducted light directly propagates from the bypass unit to the first enhanced region without passing through the reference region, so that the fourth conducted light will not be diffracted from the waveguide plate.
  • a display device includes an optical engine to form a main image and convert the main image into a plurality of input beams.
  • the device includes any one of the above-mentioned optical devices of the present invention, and expands the input beam by diffraction to form an output beam.
  • a method of displaying images using the described display device is described.
  • the present invention has the following technical effects:
  • an optical device in the present invention, can well improve the uniformity of the intensity distribution of the output light.
  • Figure 2 shows a front view of the pupil dilation device of the present invention, the pupil dilation device including a bypass unit that couples light to the enhanced area;
  • Figure 3 shows a three-dimensional view of the pupil dilation device
  • Figure 4 shows a cross-sectional side view of the pupil dilation device, including a display device supporting the pupil dilation device;
  • Fig. 5 by way of example, combines the first output light and the auxiliary output light in a three-dimensional view to form the final output light;
  • Fig. 6 shows a front view of the pupil dilation device of the present invention, with relevant dimensions and structural details marked.
  • the optical device of the present application may include a planar waveguide plate 201 with good flatness, which further includes a first optical diffraction entrance pupil unit 202, a second optical diffraction pupil expansion unit 203, and a third optical diffraction exit pupil unit 204 And the fourth optical diffraction bypass unit 205.
  • the entrance pupil unit 202 can receive the input light beam IN1, and the exit pupil unit 204 can provide an expanded output light beam OUT1 such that the length and width of the output light beam OUT1 are greater than the length and width of the input light beam IN1.
  • the pupil expanding device 2 can expand the light beam IN1 in two dimensions (e.g., in the horizontal direction SX and in the vertical direction SY).
  • the expansion process can also be called exit pupil expansion, light expansion, etc.
  • the pupil expander 2 may be called a beam expander or an exit pupil expander or the like.
  • the pupil unit 202 may be used as a coupling unit.
  • the pupil unit 202 can form the first guided light B1 and the second guided light B2 by diffracting the input light IN1.
  • the first guided light B1 and the second guided light B2 can propagate in the planar waveguide plate 201.
  • the first guided light B1 and the second guided light B2 can be confined to the planar waveguide plate 201 for total internal reflection (Total Internal Reflection).
  • the term “conduction” may mean that the light propagates inside the planar waveguide plate 201, and the light is confined inside the plate through total internal reflection (TIR).
  • TIR total internal reflection
  • the term “waveguide” may be the same as the term “optical waveguide”.
  • the first guided light B1 and the second guided light B2 may have the same wavelength ⁇ 0.
  • the first unit 202 can couple the input light IN1 to two different paths, that is, through the main path and the bypass path, and propagate to the diffractive pupil unit 204.
  • the light passing through the entrance pupil unit 202 can be coupled to the exit pupil unit 204 through the pupil dilation unit 203.
  • the pupil dilation device 2 can provide a main path from the unit 202 to the unit 204 via the unit 203.
  • the entrance pupil unit 202 can also couple light to the exit pupil unit 204 through the bypass unit 205.
  • the pupil dilation device 2 may provide a bypass path from the unit 202 to the unit 204 via the unit 205.
  • the second unit 203 can be used as a diffractive pupil dilation unit.
  • the first guided light B1 can be transmitted from the diffractive pupil unit 202 to the pupil expansion unit 203, and the direction is the first direction 301.
  • the pupil dilation unit 203 can form the expanded third guided light B3 by diffracting the first guided light B1.
  • the expanded guided light B3 can propagate from the diffractive pupil expansion unit 203 to the exit pupil unit 204.
  • the extended guided light B3 can be restricted to propagate in the waveguide plate 201 by total internal reflection.
  • the diffractive pupil dilation unit 203 can distribute the guided light B3 nearly uniformly to the entire area of the diffractive pupil unit 204.
  • the third unit 204 can be used as a diffractive exit pupil unit. As shown in Fig. 25, the exit pupil unit 204 can diffract the expanded guided light B3 to form output light OB3.
  • the fourth unit 205 can be used as a bypass unit.
  • the second guided light B2 can propagate from the first entrance pupil unit 202 to the bypass unit 205, and this direction is the second direction 302.
  • the first direction 301 represents the average propagation direction of the guided light B1.
  • the direction 301 may also indicate the central axis of the propagation of the guided light B1.
  • the second direction 302 represents the average propagation direction of the guided light B2.
  • the direction 302 may also indicate the central axis of the propagation of the guided light B2.
  • the angle ⁇ 12 is the included angle between the first direction 301 and the second direction 302, and may be in the range of 60° to 120°.
  • the bypass unit 205 forms the guided auxiliary light B4 by diffracting the second guided light B2.
  • the guided auxiliary light B4 can be restricted to propagate in the waveguide plate 201 by total internal reflection.
  • the auxiliary light B4 includes the fifth light B4a and the sixth light B4b.
  • the diffractive pupil unit 204 may include one or more enhanced regions 401, 402.
  • One or more enhanced regions 401, 402 can couple the guided auxiliary light B4 out of the waveguide plate 201 through diffraction.
  • One or more enhanced regions 401, 402 may diffract the guided auxiliary light B4 to form output enhanced light AUX3.
  • the first enhancement area (401 or 402) can diffract the guided light B3 received from the pupil dilation unit 204 and the first enhancement area, and can also diffract the guided light B4 received from the bypass unit 204 at the same time.
  • the expanded guided light B3 may propagate in the third direction 303, and the third direction 303 may be, for example, a direction substantially parallel to the second direction 302.
  • the auxiliary light B4 may propagate in a fourth direction 304, and the fourth direction 304 may be, for example, a direction substantially parallel to the first direction 301.
  • the main path represents the optical path from the entrance pupil unit 202 to the pupil expansion unit 203 via the pupil expansion unit 203.
  • the bypass path refers to the optical path from the entrance pupil unit 202 to the enhancement area 401 or 402 via the bypass unit 205.
  • the pupil dilation device 2 can make the second guided light B2 not propagate through the diffractive pupil unit 204.
  • the exit pupil unit 204 may include one or more reference regions 400 that do not diffract the fourth guided light B4 from the waveguide plate 201.
  • the total area of the reference area 400 may be in the range of 30% to 95% of the area of the exit pupil unit 204.
  • the exit pupil unit 204 may include a reference area 400 and one or more enhancement areas 401 and 402.
  • the reference area 400 forms the first output light OB3 by diffracting the transmitted light B3.
  • the enhanced areas 401 and 402 may diffract the guided light B3 to form the first output light OB3, and the enhanced areas 401 and 402 may diffract the guided light B4 to provide auxiliary output light AUX3.
  • the reference area 400 may also be referred to as a normal exit pupil area or a first exit pupil area.
  • the fourth transmitted light B4 may be transmitted from the bypass unit 205 to the first enhancement area 401 without passing through the reference area 400.
  • Another part of the fourth transmitted light B4, such as the second sixth transmitted light B4b, may propagate from the bypass unit 205 to the adjacent second enhanced region 402.
  • the reference area 400 is in the exit pupil unit 204, and will not diffract the fourth guided light B4 out of the waveguide plate 201.
  • SX, SY and SZ indicate orthogonal directions.
  • the waveguide plate 201 is parallel to the plane defined by the directions SX and SY.
  • 801 indicates the position of the first corner area 6 in the diffraction exit pupil unit 204.
  • the first corner region 6 may be the corner region with the longest path length starting from the diffractive entrance pupil unit 202.
  • 802 indicates the position of the second corner area 7 in the diffraction exit pupil unit 204.
  • the second corner area 7 is closest to the bypass unit 205.
  • 803 may indicate the center position of the exit pupil unit 204.
  • the pupil expansion device 2 includes one or more enhancement regions 401, 402 and a bypass unit 205 to increase and optimize the uniformity of the spatial intensity distribution of the output light beam OUT1.
  • the bypass unit 205 and the enhancement areas 401, 402 can provide auxiliary light AUX3, so that the intensity of the output beam OUT1 at the corner region 6 position of the farthest diffracted exit pupil unit 204 can be substantially equal to that of the output beam OUT1 at the center of the unit 204
  • the strength of 803. The longest optical path length from the diffractive entrance pupil unit 202 to the corner area 6.
  • the pupil expansion device 2 can optimize the output light beam OUT1 so that the light intensity (I801) of the output light beam OUT1 at the first lateral position (801) is substantially equal to the intensity (I803) of the output light beam OUT1 at a second lateral position (803) .
  • the relative difference (I803-I801)/I803 needs to be less than 30%, and it is better if it is less than 10%.
  • the first lateral position 801 is in the corner area 6.
  • the second lateral position 803 is at the center of the exit pupil unit 204.
  • the input beam IN1 has a propagation direction 300.
  • the input beam IN1 may correspond to a point on the displayed image.
  • the pupil expansion device 2 can convert the light of the input light beam IN1 into the output light beam OUT1, so that the output light beam OUT1 has a propagation direction 300'.
  • the direction 300' and the direction 300 are parallel.
  • the period (d) and direction ( ⁇ ) of the diffraction gratings of the units 202, 203, and 204 are carefully designed so that the direction 300 of the output light beam OUT1 is parallel to the direction 300 of the input light beam IN1.
  • the display device 500 includes a pupil dilation device 2 and an optical light engine 10.
  • the display device 500 includes an optical engine 10, which provides a main image IMG0 and converts the main image IMG0 into a plurality of input light beams IN1.
  • the light emitted from the optical engine 10 enters the diffractive pupil unit 202 of the pupil dilation device 2.
  • the multiple input light beams IN1 are diffracted by the diffractive pupil unit 202 and enter the pupil dilation device 2.
  • the display device 500 is a display device for displaying a virtual image, or a near-eye optical display device.
  • the pupil dilation device 2 can transmit the virtual image content from the optical engine 10 to the front of the user's eyes 5.
  • the pupil dilation device 2 can expand the pupil, thereby expanding the eyebox.
  • the optical engine 10 may include a micro display DISP1 to generate a main image IMG0.
  • the microdisplay DISP1 can include a two-dimensional array of light-emitting pixels.
  • the display DISP1 may be, for example, a main image IMG0 generated at a resolution of 1920 ⁇ 1080 (full HD).
  • the display DISP1 can generate a main image IMG0, for example, at a resolution of 3840 ⁇ 2160 (4K UHD).
  • the main image IMG0 may include a plurality of image points P0, P1.
  • the optical engine 10 may include a collimating optical device LNS1 to form a light beam different from each image pixel.
  • the light beam from the image point P0 of the light passes through the collimating optics LNS1 of the optical engine 10 to form a substantially collimated light beam.
  • the propagation direction of the light beam corresponding to the image point P0 is the propagation direction 300.
  • Different image points P1 have different beam propagation directions and directions 300.
  • the engine 10 may provide a plurality of light beams corresponding to the generated main image IMG0.
  • One or more light beams provided by the optical engine 10 may be coupled to the expander EPE1 as the input light IN1.
  • the optical engine 10 may include, for example, one or more light emitting diodes (LEDs).
  • the display DISP1 may include, for example, one or more microdisplay imagers, such as liquid crystal on silicon (LCOS), liquid crystal display (LCD), digital micromirror display (DMD), Micro-LED display, etc.
  • LCOS liquid crystal on silicon
  • LCD liquid crystal display
  • DMD digital micromirror display
  • Micro-LED display etc.
  • the first enhancement area (401 or 402) diffracts the guided light B3 conducted from the pupil dilation unit 203, thereby emitting the first output light OB3.
  • the first enhancement area (401 or 402) can diffract the guided light B4 conducted from the bypass unit 205, thereby forming the second auxiliary output beam component AUX3.
  • the output light OUT1 is formed in the first enhancement area (401 or 402).
  • the propagation direction of the first output beam component OB3 is the direction 300'.
  • the propagation direction of the auxiliary output beam component AUX3 is the direction 100'.
  • the pupil expanding device 2 can be designed and controlled by the grating to make the direction 100' parallel to the direction 300', so as to realize that the first output light OB3 and the second auxiliary output light AUX3 correspond to the same incident light IN1 and also correspond to the image.
  • the output beam OUT1 may be formed by the input beam IN1 such that the directions 300' and 100' are parallel to the direction 300 of the input beam IN1.
  • Each unit 202, 203, 204, 205 can contain one or more of the diffraction gratings described.
  • the grating period (d), grating direction ( ⁇ ) and grating vector (V) of the optical unit 202, 203, 204, 205 can be designed.
  • the design can realize the direction 100' of the auxiliary output beam component AUX3 and the first The direction 300' of the output beam component OB3 is parallel.
  • the grating period (d), the grating direction ( ⁇ ) and the grating vector (V), the sum of the grating vector in unit 202, the grating vector in 205, and the grating vector in area 401 is zero.
  • the grating period (d), the grating direction ( ⁇ ) and the grating vector (V), it can be realized that the sum of the grating vector of unit 202, the grating vector of 205, and the grating vector of area 402 is zero.
  • the thickness of the waveguide plate is t201.
  • the waveguide plate includes a planar waveguide core.
  • the waveguide plate 201 may optionally include, for example, one or more plating layers, one or more protective layers, and/or one or more mechanical support layers.
  • t201 refers to the thickness of the core part of the waveguide plate 201.
  • the pupil expanding device 2 can expand the light beam in two directions, the direction SX and the direction SY.
  • the width of the output beam OUT1 (in the direction SX) may be greater than the width of the input beam, and the height of the output beam OUT1 (in the direction SY) may be greater than the height of the input beam IN1.
  • the pupil dilation device 2 can expand the visual pupil of the virtual display device 500 to facilitate the positioning of the eye 5, thereby realizing a large observation range.
  • the human observer of the virtual display device 500 can see the virtual image 9 incident on the position of the observer's eye 5 at the position of the output light OUT1.
  • the output light OUT1 may include one or more output light beams, and it is characterized in that each output light beam may correspond to a different image point (P0', P1') of the virtual image.
  • the engine 10 includes a micro display for displaying the main image IMG0.
  • the optical engine 10 and the pupil expansion device 2 can convert the main image IMG0 into a display virtual image 9 with multiple input light beams LB1, and by forming the output light beam OUT1, since the input light beam IN1 to the output light OUT1 can include multiple input and output Light beam, so that each output light beam can form a different image point (P0', P1') of the virtual image 9.
  • the main image IMG0 can be graphics, text or video.
  • the optical engine 10 and the pupil expansion device 2 can display a virtual image 9 so that each image point (P0', P1') of the virtual image 9 corresponds to a different image point of the main image IMG0.
  • FIG. 5 shows that the combined output light OUT1 is formed by superimposing the first output light OB3 and the auxiliary output light AUX3.
  • the enhanced area 401 may couple the guided light B3 to the outside of the board 201 by diffraction to form the first output light OB3.
  • the enhanced area 401 can couple the guided light B4 to the outside of the board 201 through diffraction to form the auxiliary output light AUX3.
  • the enhancement area 401 may provide the first output light OB3 and the auxiliary output light AUX3 such that the auxiliary output light AUX3 overlaps the first output light OB3.
  • the enhanced area 401 may combine the output light AUX3 and the first output light OB3, that is, the auxiliary output light AUX3 overlaps the first output light OB3.
  • the enhanced area 401 provides the final output light OUT1 by combining the auxiliary output light AUX3 and the first output light OB3.
  • the reference area 400 can form the first output light OB3 by diffracting the transmitted light B3 out of the waveguide plate 201.
  • the reference area 400 can be designed so that the reference area 400 does not diffract the guided light B4, so that it does not come out of the waveguide plate 201.
  • each unit 202, 203, 204, 205 may include one or more diffraction gratings for diffracting light.
  • the unit 202 may include one or more gratings G1.
  • the unit 203 may include one or more gratings G2.
  • the unit 205 may include a grating G4.
  • the reference area 400 may include one or more gratings G3.
  • the enhancement area 401 may include one or more gratings G3A.
  • the enhancement area 402 may include one or more gratings G3B.
  • Diffraction gratings are generally described by grating period (d), grating direction ( ⁇ ) and grating vector (V).
  • the diffraction grating also includes multiple diffraction features (F), which can also be used to design and manipulate diffracted light.
  • the diffraction characteristics may be, for example, microscopic ridges or grooves, microscopic protrusions (or depressions), wherein the protrusions (or depressions) in adjacent rows can be used as diffraction lines.
  • the grating vector (V) is defined as a vector having a direction perpendicular to the diffraction line of the diffraction grating and having a magnitude of 2 ⁇ /d, where d is the grating period.
  • the diffractive pupil unit 202 has grating vectors V11 and V12.
  • the diffractive pupil expansion unit 203 has a grating vector V21.
  • the bypass unit 205 has a raster vector V41.
  • the reference area 400 has a raster vector V31.
  • the enhanced area 401 has grating vectors V31, V3A.
  • the enhanced area 402 has raster vectors V31, V3B.
  • the grating vector V11 has a direction ⁇ 11 and a magnitude 2 ⁇ /d11.
  • the grating vector V12 has a direction ⁇ 12 and a magnitude 2 ⁇ /d12.
  • the grating vector V21 has a direction ⁇ 21 and a magnitude.
  • the grating vector V31 has a direction ⁇ 31 and a magnitude 2 ⁇ /d31.
  • the grating vector V41 has a direction ⁇ 41 and a magnitude of 2 ⁇ /d41.
  • the grating vector V3A has a direction ⁇ 3A and a magnitude of 2 ⁇ /d3A.
  • the grating vector V3B has a direction ⁇ 3B and a magnitude of 2 ⁇ /d3B.
  • the grating vector direction ( ⁇ ) can be specified as, for example, the angle between it and the reference direction (for example, the direction SX).
  • the grating period (d) of the optical units 202, 203, 204, and 205 and the orientation ( ⁇ ) of the grating vector V can be selected so that the direction 100 of the auxiliary output beam component AUX3 is parallel to the direction 300' of the first output beam component OB3.
  • the angle between the directions of the grating vectors V12 and V11 of the diffraction entrance pupil unit 202 may be, for example, in the range of 60° to 120°.
  • the grating period d12 of the unit 202 may be substantially equal to the grating period d11.
  • the grating period d12 of the unit 202 may also be equal to the grating period d11.
  • the grating period (d) and direction ( ⁇ ) of the grating vector (V11, V21, V31) can be designed to satisfy, for example, that the vector sum of the grating vectors (V11, V21, V31) of the units 202, 203, 204 is zero.
  • the grating vectors V11, V21, and V31 are controlled so that the vector sum of the grating vectors V11, V21, and V31 is zero.
  • the grating period (d) and the direction of the grating vector ( ⁇ ) can be designed to satisfy, for example, that the sum of the grating vector of the unit 202, the grating vector of the unit 205, and the grating vector of the area 401 is zero.
  • the grating periods d12, d41, d3A and the grating vectors V12, V41, and V3A in the directions ⁇ 12, ⁇ 41, and ⁇ 3A can be designed such that, for example, the vector sum of the grating vectors V12, V41, and V3A is zero.
  • the grating vector V3B may be parallel to the grating vector V3A, so the grating period d3B may be equal to the grating period d3A.
  • the grating period (d) and the direction of the grating vector ( ⁇ ) can be satisfied by design.
  • the sum of the grating vector of unit 202, the grating vector of unit 205, and the grating vector of area 402 is zero.
  • the first unit 202 may have a first grating vector V11 to form the first guided light B1 along the direction 301, and a second grating vector V12 to form the second guided light B2 along the direction 302.
  • the first unit 202 may have a first diffractive feature F11, a first grating period d11 and a first orientation ⁇ 11 (relative to the reference direction SX).
  • the first unit 202 may have a second diffraction feature F12, a second grating period d12 and a second orientation ⁇ 12 (relative to the reference direction SX).
  • the first unit 202 may be, for example, a grating as shown in the figure realized by a crossed grating or by two linear gratings.
  • the first linear grating with the feature F11 may be arranged on the first side of the board 201 (for example, on the input side SRF1), and the second linear grating with the characteristic F12 may be arranged on the second side of the waveguide plate 201 (for example, on the On the output side SRF2).
  • the characteristic structure of the diffraction grating can be, for example, microscopic ridges or tiny protrusions.
  • the second unit 203 may have a first grating vector V21, so that the first guided light B1 is diffracted to form the third guided light B3.
  • the grating G2 of the second unit 203 may have a diffraction feature F21, which has a grating period d21 and an orientation ⁇ 21 (relative to the reference direction SX).
  • the third unit 204 may have a first grating vector V31, so as to diffractically couple the expanded light B3 out of the waveguide plate 201.
  • the grating G3 of the third unit 204 may have a diffraction feature F31, which has a grating period d31 and an orientation ⁇ 31 (relative to the reference direction SX).
  • the reference area 400 may have a first grating vector V31 so as to diffract and couple the expanded light B3 out of the report board 201.
  • the grating G3A of the reference region 400 may have a diffraction feature F31 having a grating period d31 and an orientation ⁇ 31 (relative to the reference direction SX).
  • the diffractive exit pupil unit 204 may include one or more reference regions 400 that will not diffract the fourth transmitted light B4 out of the waveguide plate 201.
  • the region 400 may have a low or negligible diffraction efficiency, and diffract the guided light B4 out of the waveguide plate 201.
  • the reference region 400 has a low or negligible output coupling efficiency for the guided light propagating in the first direction 301.
  • the region 400 couples the output light of the guided light propagating along the first direction 301 into the output light of the observation direction (300), and couples the output light of the guided light propagating along the second direction 302 into the output light of the observation direction (300).
  • the coupling efficiency of the former is 10% or less of the latter.
  • the bypass unit 205 may have a first grating vector V41 to form the second transmitted light B2 by diffracting to generate the transmitted light B4.
  • the grating G4 of the bypass unit 205 may have a diffractive feature F41 with a grating period d41 and an orientation ⁇ 41 (relative to the reference direction SX).
  • the enhanced regions 401 and 402 may have a first grating vector V31, which diffracts the expanded light B3 out of the waveguide plate 201.
  • the gratings of the enhanced regions 401, 402 may have diffractive features F31 with a grating period d31 and an orientation ⁇ 31 (relative to the reference direction SX).
  • the enhanced regions 401, 402 may have one or two different grating vectors V3A, V3B, which diffract and couple the transmitted light B4 out of the waveguide plate 201.
  • the grating G3A in the enhanced region 401 may have a diffraction function F3A, which has a grating period d3A and an orientation ⁇ 3A (relative to the reference direction SX).
  • the grating G3B in the enhanced region 402 may have a diffractive feature F3B, a grating period d3B and an orientation ⁇ 3B (relative to the reference direction SX).
  • the enhanced regions 401, 402 can be implemented by a cross grating, such as a cross grating or two linear gratings.
  • the first linear grating G3A has the feature F3A and can be set on the first side (for example, SRF1) of the report board 201
  • the second linear grating G3 has the feature F31 and can be set on the second side (for example, SRF2) of the board 201 .
  • the enhanced regions 401, 402 may have high output coupling efficiency for diffractively coupling the light guide B3 out of the waveguide plate 201, and the enhanced regions 401, 402 may have high output coupling efficiency for coupling the conducted light B4 out of the waveguide plate 201.
  • the efficiency of the first enhanced region 401 to couple the light propagating in the first direction 301 to the viewing direction (300) may be approximately equal to that of the first enhanced region 401 to couple the light propagating in the second direction 302 to the viewing direction.
  • the efficiency of (300) is more than 50%.
  • L14 represents the distance between cell 202 and cell 205.
  • the distance L14 may be 50% to 80% of the height h3 of the unit 204.
  • the positions and sizes of the units 202, 204, and 205 can be set so that the second guided light (B2) does not interact with the coupling unit 204 between the entrance pupil unit 202 and the pupil expansion unit 203.
  • the pupil dilation device 2 may be designed such that the second guided light B2 does not propagate through the diffractive pupil unit 204.
  • the first unit 202 may have a width w1 and a height h1.
  • the second unit 203 may have a width w2 and a height h2.
  • the third unit 204 may have a width w3 and a height h3.
  • the fourth unit 205 may have a width w4 and a height h4.
  • the width represents the size in the direction SX
  • the height represents the size in the direction SY.
  • the exit pupil unit 204 may be rectangular. The edges of the diffractive pupil unit 204 are along the directions SX and SY, respectively.
  • the width W2 of the pupil dilation unit 203 is much larger than the width w1 of the entrance pupil unit 202.
  • the width of the expanded guided beam B3 is much larger than the width of the input beam IN1.
  • the 803 denotes the center point of the diffractive pupil unit 204.
  • the position 800 indicates the position of the diffraction exit pupil unit 204 that is closest to the unit 202.
  • the position 801 may be the region 6 of the farthest angle of the exit pupil unit 204.
  • the horizontal distance between the positions 800 and 801 may be, for example, 90% of the width w3 of the diffractive pupil unit 204.
  • the vertical distance between the positions 800 and 801 may be, for example, 90% of the height h3 of the diffractive pupil unit 204.
  • the position 802 is located in the second corner area 7 and is closest to the position of the bypass unit 205.
  • the waveguide plate 201 may be composed of a transparent solid material.
  • the waveguide plate 201 can be made of, for example, glass, polycarbonate, or polymethylmethacrylate (PMMA).
  • the diffractive optical units 202, 203, 204, 205 may be formed, for example, by means of molding, embossing and/or etching, holographic exposure and the like.
  • the units 202, 203, 204, and 205 may be realized by, for example, one or more surface diffraction gratings or one or more volume holographic diffraction gratings.
  • the input light IN1 may be substantially monochromatic or a different input wavelength ⁇ 0. All light beams IN1, B1, B2, B3, B4, OUT1, OB3, and AUX1 can have the same wavelength ⁇ 0.
  • the spatial distribution of diffraction efficiency can be controlled by selecting the local parameters of the microscopic diffraction feature F.
  • the parameters of the microscopic diffraction characteristic F of the exit pupil unit 204 can be controlled to further improve the uniformity of the intensity distribution of the output light OUT1.
  • the display device 500 may be a virtual reality device 500 or an augmented reality device 500.
  • the display device 500 may be a near-eye device, or a wearable device, such as a headset.
  • the device 500 can be used for, for example, a headband, through which the device 500 can be worn on the head of a user.
  • the diffractive pupil unit 204 of the device 500 is placed in front of the left eye 5 or the right eye 5 of the user.
  • the device 500 can project the output light OUT1 into the user's eye 5.
  • the device 500 may include two engines 10 and/or two pupil dilation devices 2 to display stereoscopic images.
  • the engine 10 may generate still images and/or videos.
  • the engine 10 can generate a real main image IMG0 from the digital image.
  • the engine 10 may receive one or more digital images from an internet server or from a smart phone.
  • the device 500 may be a smart phone.
  • the displayed image may be seen by humans, and the displayed image may also be viewed by, for example, an animal or a machine (which may include, for example, a camera)

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Diffracting Gratings Or Hologram Optical Elements (AREA)

Abstract

一种光学器件（10）、显示设备（500）及其输出光和显示图像的方法，光学器件（10）包括：波导板（201），其包括：衍射入瞳单元（202），其通过衍射输入光束（IN1）而形成第一传导光（B1）和第二传导光（B2）；衍射扩瞳单元（203），其通过衍射第一传导光（B1）以形成第三传导光（B3）；衍射出瞳单元（204），其通过衍射第三传导光（B3）形成第一输出光（OB3）；旁路单元（205），其通过使第二传导光（B2）衍射而形成第四传导光（B4）；其中，第一传导光（B1）沿第一方向（301）传播，第二传导光（B2）沿第二方向（302）传播，并且第一方向（301）和第二方向（302）之间的夹角在60°至120°的范围内；其中衍射出瞳单元（204）包括一个或多个增强区域（401，402），以通过衍射第四传导光（B4）形成辅助输出光（AUX3）。光学器件可以很好的提升输出光的强度分布均匀性。

Description

一种光学器件、显示设备及其输出光和显示图像的方法 技术领域
本发明涉及光学器件技术领域，特别涉及一种光学器件、显示设备及其输出光和显示图像的方法。
背景技术
参照图1，扩瞳器件1包括波导板101，该波导板又包括衍射入瞳单元102，衍射扩瞳单元103和衍射出瞳单元104。一束输入光束IN1在扩瞳器件1中，通过多次衍射进行扩大，最后输出光束OUT1。该耦合入瞳单元102通过衍射，将输入光IN1衍射成第一传导的光B1。通过扩瞳单元103使第一传导光B1衍射而形成扩展的传导光B3。通过所述衍射出瞳单元104将扩散的传导光B3衍射输出为光OUT1。
扩瞳器件1可以在方向SX和在方向SY这两个方向上扩展光束。输出光束OUT1的宽度远大于输入光束IN1的宽度。扩瞳器件1可以用于扩展虚拟显示设备的视瞳，以便于眼睛105相对于虚拟显示设备的观察位置有更大的舒适观察位置(大eyebox)。观察者的眼睛105可以在输出光束的观察位置内看到完成的虚拟图像。输出光可以包括一个或多个输出光束，其中每个输出光束可以对应于显示的虚拟图像的不同图像位置。扩瞳器件也可以称为例如扩展器件，扩展器件等。
在波导板101中传播的传导光(B1，B3)的强度随着其在扩瞳器件103中传播路程长度的增加而减小。同时，该传导光在扩瞳单元103中经过了非常多次独立的衍射，衍射的次数和传播的的距离成正比。由于从入瞳单元102到所述拐角区域6的光路较长，因此最远(最左)拐角区域6的输出强度可能较低。 而且，扩瞳单元103也会进一步减小出光强度。
因此，在衍射出瞳单元104的最远处的角区域6的输出光的强度会比在衍射出瞳单元104的中心106的输出光的强度低很多。最终导致图1中的的扩瞳器件1的输出光的空间强度分布可能是不均匀的。
发明内容
为了克服现有技术的上述缺陷，本发明提供一种光学器件、显示设备及其输出光和显示图像的方法，以解决上述背景技术中提出的问题。
本发明解决现有技术中的问题所采用的技术方案为：一种光学器件，包括：
波导板，其包括：
衍射入瞳单元，其通过衍射所述输入光而形成第一传导光和第二传导光；
衍射扩瞳单元通过衍射所述第一传导光以形成第三传导光；
衍射出瞳单元通过衍射所述第三传导光形成第一输出光；
旁路单元，其通过使第二传导光衍射而形成第四传导光；
其中，第一传导光沿第一方向传播，第二传导光沿第二方向传播，并且第一方向和所述第二方向之间的夹角在60°至120°的范围内；
其中衍射出瞳单元包括一个或多个增强区域，以通过衍射第四传导光形成辅助输出光。
作为本发明的优选方案，所述衍射出瞳单元包括一个或多个所述区域，所述区域不使第四传导光从波导板中衍射出来。
作为本发明的优选方案，所述第三传导的光的传播方向是第三方向且基本平行与所述第二方向；其中所述第四传导光传播方向是在第四方向，且基本平 行与所述第一方向。
作为本发明的优选方案，所述第一增强区域通过使第三导光衍射而形成第一输出光，同时通过衍射第四传导光以形成辅助输出光，并且通过将辅助输出光与第一输出光叠加来形成组合输出光。
作为本发明的优选方案，所述入瞳单元和旁路单元之间的距离是在输出耦合区域高度的50％至80％范围内；所述第二传导的光的器件在入瞳单元和扩瞳单元之间，不与所述衍射出瞳单元相互作用。
作为本发明的优选方案，所述输衍射出瞳单元包括一个或多个基准区域，它们不使第四导光从波导板中衍射出来，其中基准区域的总面积在出瞳单元面积的30％至95％。
作为本发明的优选方案，至少有一部分的所述第四传导的光从所述旁路单元直接传播至第一增强区域而不经过的基准区域，不会使第四传导光从波导板衍射。
一种显示设备，包括光学引擎以形成主图像并将主图像转换为多个输入光束，该设备包括本发明的光学器件上述中的任一项，通过衍射扩展输入光束形成输出光束。
使用以上所述任一项所述的器件来提供输出光的方法作为本发明的优选方案。
使用所述的显示设备来显示图像的方法。
与现有技术相比，本发明具有以下技术效果：
本发明中一种光学器件、显示设备及其输出光和显示图像的方法，该光学 器件可以很好的提升输出光的强度分布均匀性。
附图说明
图1相关案例，一种光学扩瞳器件；
图2显示了本发明扩瞳器件的正视图，该扩瞳器件包括将光耦合到增强区域的旁路单元；
图3显示了扩瞳器件的三维视图；
图4显示了扩瞳器件的横截面侧视图，包括扩瞳器件配套的显示设备；
图5以实例的方式，在三维视图中，将第一输出光与辅助输出光结合，形成最终输出光；
图6显示了本发明扩瞳器件的正视图，并标注的相关尺寸和结构细节。
具体实施方式
下面结合附图对本发明的具体实施方式作进一步说明。在此需要说明的是，对于这些实施方式的说明用于帮助理解本发明，但并不构成对本发明的限定。此外，下面所描述的本发明实施方式中所涉及的技术特征只要彼此之间未构成冲突就可以相互组合。
本申请的光学器件即扩瞳器件2可以包括平面度好的平面波导板201，其又包括第一光学衍射入瞳单元202，第二光学衍射扩瞳单元203，第三光学衍射出瞳单元204和第四光学衍射旁路单元205。
入瞳单元202可以接收输入光束IN1，而出瞳单元204可以提供扩展的输出光束OUT1，使得输出光束OUT1的长度和宽度大于输入光束IN1的长度和宽度。
扩瞳器件2可以在二维上(例如，沿水平方向SX和沿垂直方向SY)扩展 光束IN1。扩展过程也可以称为出瞳扩展，光线扩展等。扩瞳器件2可以称为光束扩展器或出射光瞳扩展器等。
入瞳单元202可以用作耦合单元。入瞳单元202可以通过衍射输入光IN1来形成第一传导光B1和第二传导光B2。第一传导光B1和第二传导光B2可在平面波导板201内传播。第一传导光B1和第二传导光B2可以被限制在所述平面波导板201进行全内反射(Total Internal Reflection)。
其中术语“传导”可能意味着该所述光在平面波导板201内部传播，通过全内反射(TIR)将光线限制在板内部。术语“波导”可以与术语“光波导”相同。
第一传导光B1和第二传导光B2可以具有相同的波长λ0。所述第一单元202可将输入光IN1耦合到两条不同的路径，即通过主路径和旁路路径，传播到衍射出瞳单元204。
经过入瞳单元202的光线，可以通过扩瞳单元203将光线耦合到出瞳单元204。扩瞳器件2可以提供从单元202经由单元203到单元204的主路径。
入瞳单元202也可以通过旁路单元205将光线耦合到出瞳单元204。扩瞳器件2可以提供从单元202经由单元205到单元204的旁路路径。
第二单元203可以用作衍射扩瞳单元。首先第一传导光B1可以从衍射入瞳单元202传导至扩瞳单元203，该方向是第一方向301。所述扩瞳单元203可以通过衍射第一传导光B1，从而形成扩展后的第三传导光B3。扩展后的传导光B3可以从衍射扩瞳单元203传播到出瞳单元204。扩展的传导光B3可以通过全内反射限制在波导板201中传播。在本实施例中，衍射扩瞳单元203可以将传导光B3接近均匀的分配到衍射出瞳单元204的整个区域。
第三单元204可以用作衍射出瞳单元。外出如图25所示，出瞳单元204可 以将扩展的传导光B3衍射而形成输出光OB3。
第四单元205可以用作旁路单元。第二传导光B2可以从第入瞳单元202传播到旁路单元205，此方向是第二方向302。
第一方向301代表着所述被传导光B1的平均传播方向。方向301也可以表示被传导光B1的传播的中心轴。
第二方向302代表着所述被传导光B2的平均传播方向。方向302也可以表示被传导光B2的传播的中心轴。
角度γ12是第一方向301和第二方向302之间的夹角，可以是60°至120°的范围内。
旁路单元205通过使第二传导光B2衍射而形成传导辅助光B4。传导的辅助光B4可以通过全内反射被限制在波导板201中传播。其中传导辅助光B4包括第五传导光B4a和第六传导光B4b。衍射出瞳单元204可以包括一个或多个增强区域401，402。一个或多个增强区域401，402可以通过衍射将传导的辅助光B4耦合出波导板201。一个或多个增强区域401，402可通过将传导的辅助光B4进行衍射，从而形成输出增强光AUX3。
第一增强区域(401或402)可以衍射从扩瞳单元204和所述第一增强区域接收的传导光B3，还可以同时衍射从旁路单元204接收的传导光B4。
扩展后的传导光B3可以在第三方向303上传播，第三方向303可以是，例如与第二方向302基本上平行的方向。该辅助的光B4可以在第四方向304上传播，该第四方向304可以是，例如与第一方向301基本平行的方向。
主路径表示从入瞳单元202到扩瞳单元203经由扩瞳单元203的光路。
旁路路径指的是从入瞳单元202经由旁路单元205到增强区域401或402的光路。
在一个实施例中，扩瞳器件2可以使得第二传导光B2不经由衍射出瞳单元204传播。
出瞳单元204可以包括一个或多个基准区域400，该基准区域400不使第四传导光B4从波导板201中衍射出来。基准区域400的总面积可以是出瞳单元204的面积的30％至95％的范围内。
出瞳单元204可以包括基准区域400和一个或多个增强区域401，402。该基准区域400通过衍射被传导的光B3来形成第一输出光OB3。增强区域401，402可以通过衍射传导光B3来形成第一输出光OB3，并且增强区域401，402可以通过衍射传导光B4来提供辅助输出的辅助光AUX3。基准区域400也可以被称为正常的出瞳区域或第一出瞳区域。
在一个实施例中，第四传导光B4的至少一部分，比如第五传导光B4a可以从旁路单元205传导到第一增强区域401而不通过基准区域400。第四传导光B4的另一部分，例如第二六传导光B4b，可以从旁路单元205传播到相邻的第二增强区域402。基准区域400在出瞳单元204中，且不会将第四传导光B4衍射出波导板的201。
SX，SY和SZ表示正交方向。波导板201与方向SX和SY限定的平面平行。
801表示第一拐角区域6在衍射出瞳单元204中的位置。与衍射出瞳单元204的其他转角区域相比，第一个转角区域6可能是从衍射入瞳单元202出发的最长路径长度的转角区域。802表示第二拐角区域7在衍射出瞳单元204中的位 置。第二拐角区域7是最接近于所述旁路单元205的。803可以表示出瞳单元204的中心位置。
参照图3，扩瞳器件2包括一个或多个增强区域401，402和一个旁路单元205从而增加和优化输出光束OUT1的空间强度分布的均匀性。例如，旁路单元205和增强区域401，402可以提供辅助光AUX3，使得输出光束OUT1在衍射出瞳单元204的最远处的拐角区域6位置的强度可以基本上等于输出光束OUT1在单元204中心803的强度。从衍射入瞳单元202到拐角区域6具有的最长的光学路径长度。
扩瞳器件2可以优化输出光束OUT1，使得在第一横向位置(801)处的输出光束OUT1的光强度(I801)基本上等于输出光束OUT1在一个第二横向位置(803)的强度(I803)。该相对差(I803-I801)/I803需要小于30％，若小于10％更好。第一横向位置801在该拐角区域6里。第二横向位置803在出瞳单元204的中心。
输入光束IN1具有传播方向300。输入光束IN1可以对应于显示图像上的一个点。扩瞳器件2可以将输入光束IN1的光转换成输出光束OUT1，使得输出光束OUT1具有传播方向300'。通过扩瞳器件2将光输入光束IN1转换成输出光束OUT1后，方向300'与方向300是平行的。单元202，203，204的各个衍射光栅的周期(d)和方向(β)是经过精心设计的，从而使得输出光束OUT1的方向300与输入光束IN1的方向300平行。
参照图4，显示设备500包含扩瞳器件2和一个光学光引擎10。所述显示设备500包含一个光学引擎10，光学引擎10提供一个主图像IMG0，并将主图像IMG0转换为多个输入光的光束IN1。光学引擎10发出的光入射到扩瞳器件 2的衍射入瞳单元202中。所述多个的输入光的光束IN1通过衍射入瞳单元202的衍射，进入导扩瞳器件2中。显示设备500是用于显示虚拟图像的显示设备，或者说是近眼光学显示设备。
扩瞳器件2可以将来自光学引擎10的虚拟图像内容传导到用户的眼睛5前面。扩瞳器件2可以扩展视瞳，从而扩大了eyebox。
该光学引擎10可包括一个微型显示器DISP1以产生一个主图像IMG0。在微型显示器DISP1可以包括一个二维阵列式的发光像素。显示器DISP1可以是例如以1920×1080(全高清)的分辨率生成的主图像IMG0。所述显示DISP1可以生成一个主图像IMG0例如在一个分辨率为3840×2160(4K UHD)。主图像IMG0可包括多个的图像点P0，P1。光学引擎10可以包括准直光学器件LNS1，以形成与每个图像像素不同的光束。从光的图像点P0的光束，通过光学引擎10的准直光学器件LNS1，以形成一束基本上准直的光束。对应于图像点P0的光束传播方向是传播方向300。不同的图像点P1的光束传播方向与方向300不同。引擎10可以提供与所生成的主图像IMG0相对应的多个光束。光学引擎10提供的一个或多个光束可以耦合到扩展器EPE1作为输入光IN1。
该光学引擎10可以包括例如一个或多个光发射二极管(LED)。所述显示DISP1可以包括例如一台或多台微显示器成像仪，例如硅基液晶(LCOS)，液晶显示器(LCD)，数字微镜显示器(DMD)，Micro-LED显示器等。
该第一增强区域(401或402)通过衍射从扩瞳单元203传导来的传导光B3，从而出射第一输出光OB3。第一增强区域(401或402)可以通过衍射从旁路单元205传导来的传导光B4，从而形成第二辅助输出光束分量AUX3。通过将第二输出光束分量AUX3与第一输出光束分量OB3叠加，从而在第一增强区域 (401或402)形成输出光OUT1。
所述第一输出光束分量OB3的传播方向是方向300’。辅助输出光束分量AUX3的传播方向是方向100'。该扩瞳器件2可以通过光栅的设计和控制，使方向100’与方向300’平行，从而实现第一输出光OB3和第二辅助输出光AUX3对应于同一束入射光IN1，同时也对应于图像上的同一点(例如P0)。输出光束OUT1可以由输入光束IN1形成，使得方向300’和100'与输入光束IN1的方向300平行。
每个单元202，203，204，205都可以包含一个或多个描述中的衍射光栅。
光学单元的202，203，204，205的光栅周期(d)，光栅方向(β)和光栅矢量(V)是可以设计的，通过设计可以实现该辅助输出光束分量AUX3的方向100'与第一输出光束分量OB3的方向300’平行。
通过设计光栅周期(d)，光栅方向(β)和光栅矢量(V)可以实现，单元202的光栅矢量，205中的光栅矢量，区域401的光栅矢量之和为零。
通过设计光栅周期(d)，光栅方向(β)和光栅矢量(V)可以实现，单元202的光栅矢量，205的光栅矢量，和区域402的光栅矢量之和是零。
波导板的厚度是t201。波导板包括一个平面波导核心。在一个实施例中，所述波导板201可任选地包括例如，一个或多个镀层，一个或多个保护层，和/或一个或多个机械支撑层。t201是指波导板201的核心部分的厚度。
扩瞳器件2可以在方向SX和方向SY两个方向上扩展光束。输出光束OUT1的宽度(在方向SX上)可以大于输入光束的宽度，并且输出光束OUT1的高度(沿方向SY)可以大于输入光束IN1的高度。
扩瞳器件2可以扩展虚拟显示设备500的视瞳，以便于眼睛5的定位，从 而实现大的观察范围。对于虚拟显示设备500的人的观察者可以看到在输出光OUT1位置入射到观看者眼睛5位置的虚拟图像9。输出的光OUT1可包括一个或多个输出的光的光束，其特征在于，每个输出光束可以对应于虚拟图像的不同的图像点(P0'，P1')。引擎10包括用于显示主图像IMG0的微型显示器。光学引擎10和扩瞳器件2可以把主图像IMG0转换成具有多个输入光束LB1的显示虚拟图像9，并且通过形成输出光束OUT1，由于从输入光束IN1到输出光OUT1可以包括多个输入和输出光束，使得每个输出光束可以形成虚像9的不同像点(P0'，P1')。所述主图像IMG0可以是图形，文字或视频。该光学引擎10和所述扩瞳器件2可以显示虚拟图像9，并使得虚像9的每个图像点(P0'，P1')对应于主图像IMG0的不同图像点。
图5展示出了，通过将第一输出光OB3与辅助输出光AUX3叠加而形成组合的输出光OUT1。
增强区域401可以通过衍射将传导光B3耦合到板201之外而形成第一输出光OB3。增强区域401可以通过衍射将传导光B4耦合到板201之外，来形成辅助输出光AUX3。增强区域401可以提供第一输出光OB3和辅助输出光AUX3使得辅助输出光AUX3与第一输出光OB3重叠。所述增强区域401可以组合输出光AUX3与所述第一输出光OB3，即该辅助输出光AUX3与第一输出光OB3重叠。增强区域401通过组合辅助输出光AUX3和第一个输出光OB3，提供最后的输出光OUT1。
该基准区域400可以通过把传导的光B3衍射出波导板201，从而形成第一输出光OB3。基准区域400可以通过设计，使得所述基准区域400对传导光B4不发生衍射，从而不会从所述波导板201中出来。
参照图6，每个单元202，203，204，205可包括一个或多个衍射光栅，用于对光进行衍射。例如，单元202可包括一个或多个光栅G1。例如，单元203可以包括一个或多个光栅G2。例如，单元205可包括一个光栅G4。为例子，该基准区域400可以包括一个或多个光栅G3。例如，增强区域401可以包括一个或多个光栅G3A。例如，增强区域402可以包括一个或多个光栅G3B。
衍射光栅一般通过光栅周期(d)，光栅方向(β)和光栅矢量(V)来描述。另外，衍射光栅还有包括多个衍射特征(F)，其也可以用于设计和操作衍射光线。该衍射特性可以是，例如微观的脊或凹槽，微观突起(或凹陷)，其中相邻行的突起(或凹陷)可以用作衍射线。将光栅矢量(V)定义为具有垂直于衍射光栅的衍射线的方向，并且其大小为2π/d的矢量，其中d是光栅周期。
衍射入瞳单元202具有光栅矢量V11，V12。衍射扩瞳单元203具有一个光栅矢量V21。所述旁路单元205具有光栅矢量V41。基准区域400具有光栅矢量V31。所述增强区域401具有光栅矢量V31，V3A。增强区域402具有光栅矢量V31，V3B。光栅矢量V11具有方向β11和大小2π/d11。光栅矢量V12具有方向β12和大小2π/d12。光栅矢量V21具有方向β21和大小。光栅矢量V31具有方向β31和大小2π/d31。光栅矢量V41具有方向β41和大小2π/d41。光栅矢量V3A具有方向β3A和大小2π/d3A。光栅矢量V3B具有方向β3B和大小2π/d3B。光栅矢量方向(β)的可以被指定为，例如其和参考方向(例如，方向SX)之间的角度。
可以选择光学单元202，203，204，205的光栅周期(d)和光栅矢量V的取向(β)，使得辅助输出光束分量AUX3的方向100与第一输出光束分量OB3的方向300’平行。
衍射入瞳单元202的光栅矢量V12，V11的方向之间的角度可以例如在60°至120°的范围内。所述单元202的光栅周期d12的可以是基本上等于光栅周期d11。所述单元202的光栅周期d12的也可以是等于光栅周期d11。
光栅矢量(V11，V21，V31)的光栅周期(d)和方向(β)可以通过设计，满足例如单元202，203，204的光栅矢量(V11，V21，V31)的矢量之和是零。具体是通过光栅周期d11，d21，d31和该方向β11，β21，β31的细节设计，控制光栅矢量V11，V21，V31，使得光栅矢量V11，V21，V31的矢量和为零。
光栅周期(d)和光栅矢量的方向(β)可以通过设计满足例如，单元202的光栅矢量的矢量，单元205的光栅矢量，和区域401的光栅矢量三者之和为零。
光栅周期d12，d41，d3A和方向β12，β41，β3A的光栅矢量V12，V41，V3A可通过设计，使得例如所述光栅矢量V12，V41，V3A的矢量和是零。
光栅矢量V3B可以是平行与所述光栅矢量V3A，因此光栅周期d3B可以等于光栅周期d3A。
光栅周期(d)和光栅矢量的方向(β)可以通过设计满足，例如，单元202的光栅矢量，单元205的光栅矢量，区域402的光栅矢量三者之和为零。
第一单元202可以具有第一光栅矢量V11以形成沿方向301的第一传导光B1，以及第二光栅矢量V12以形成沿方向302的第二传导光B2。第一单元202可以具有第一衍射特征F11，具有第一光栅周期d11和第一取向β11(相对于基准方向SX)。所述第一单元202可以具有第二衍射特征F12，具有第二光栅周期d12和第二取向β12(相对于基准方向SX)。第一单元202可以是，例如通过交叉光栅或通过两个线性光栅实现的图中所示的光栅。具有特征F11的第一线性 光栅可以被设置在板201的第一侧(例如在输入侧SRF1上)，并且具有特征F12的第二线性光栅可以被设置在波导板201的第二侧(例如在输出侧SRF2上)。衍射光栅的特征结构可以是，例如微观的山脊或微小突起。
第二单元203可以具有第一光栅矢量V21，从而使第一传导光B1衍射形成第三传导光B3。所述第二单元203的光栅G2可以具有衍射特征F21，其具有光栅周期d21和一个取向β21(相对于基准方向SX)。
第三单元204可以具有第一光栅矢量V31，从而将扩展的光B3衍射耦合出波导板201。第三单元204的光栅G3可以具有衍射特征F31，其具有光栅周期d31和一个取向β31(相对于基准方向SX)。
基准区域400可以具有第一光栅矢量V31，从而将扩展的光B3衍射耦合出报道板201。基准区域400的光栅G3A可以具有衍射特征F31，其具有光栅周期d31和一个取向β31(相对于基准方向SX)。
在一个实施例中，所述衍射出瞳单元204可包括一个或多个基准区域400，其不会衍射第四传导的光B4出波导板201。
在一个实施例中，所述区域400可以具有低的或可忽略不计的衍射效率，把传导的光B4衍射出波导板201。在一个实施例中，对于传播在所述第一方向301的传导光，基准区域400具有低或可忽略的输出耦合效率。例如，区域400对沿着第一方向301传播的传导光输出耦合为观察方向(300)的出射光，与其对沿着第二方向302传播的传导光输出耦合为观察方向(300)的出射光，前者的耦合效率为后者耦合效率的10％或更低。
所述旁路单元205可以有一个第一光栅矢量V41以形成通过衍射所述第二传导的光B2从而产生传导光B4。旁通单元205的光栅G4可以具有衍射特征 F41，其具有光栅周期d41和一个取向β41(相对于基准方向SX)。
增强区域401，402可以具有第一光栅矢量V31，将扩展光B3衍射耦合出的波导板201。增强区域401，402的光栅可以具有衍射特征F31，具有光栅周期d31和一个取向β31(相对于基准方向SX)。
增强区域401，402可以具有一个或两个不同的光栅矢量V3A，V3B，将传导的光B4衍射耦合出波导板201的。在增强区域401的光栅G3A可以有衍射功能F3A，其具有光栅周期d3A和一个取向β3A(相对于基准方向SX)。在增强区域402的光栅G3B可以有衍射特征F3B，具有光栅周期d3B和一个取向β3B(相对于基准方向SX)。
增强区域401，402可以通过十字光栅来实现，例如交叉光栅或两个线性光栅。第一线性光栅G3A具有特征F3A，可以被设置在报导板201的第一侧(例如SRF1)上，第二线性光栅G3具有特征F31，可以被设置在板201的第二侧(例如SRF2)上。
增强区域401，402可以具有用于将导光B3衍射耦合出波导板201的高输出耦合效率，并且增强区域401，402可以具有用于将传导光B4耦合出波导板201的高输出耦合效率。
第一增强区域401的把传播在所述第一方向301的光耦合到观察方向(300)的效率，可以约为第一增强区域401把传播在所述第二方向302的光耦合到观察方向(300)的效率的50％以上。
L14表示单元202和单元205之间的距离。距离L14可以为单元204高度h3的50％至80％。
可以通过设置单元202，204，205的位置和尺寸，使得第二传导光(B2) 不与入瞳单元202和扩瞳单元203之间的耦合单元204相互作用。
扩瞳器件2可以设计成使得第二传导光B2不经由衍射出瞳单元204传播。
第一单元202可以具有宽度w1和高度h1。第二单元203可以具有宽度w2和高度h2。第三单元204可以具有宽度w3和高度h3。第四单元205可以具有宽度w4和高度h4。宽度表示方向SX上的尺寸，高度表示方向SY上的尺寸。出瞳单元204可以为矩形。所述衍射出瞳单元204的边缘分别沿着方向SX和SY。
所述扩瞳单元203的宽度W2比入瞳单元202的宽度w1大很多。扩展的传导光束B3的宽度比输入光束IN1的宽度大很多。
803表示所述衍射出瞳单元204的中心点。位置800表示衍射出瞳单元204中最接近单元202的位置。位置801可以是出瞳单元204的最远角的区域6。位置800，801之间的水平距离可以是，例如衍射出瞳单元204的宽度w3的90％。位置800，801之间的垂直距离可以是，例如衍射出瞳单元204的高度h3的90％。位置802位于所述第二角部区域7，最接近旁路单元205的位置。
波导板201可以由透明固体材料组成。波导板201可以是，例如玻璃，聚碳酸酯或聚甲基丙烯酸甲酯(PMMA)等材质。衍射光学单元202，203，204，205可以是，例如通过模制，压花和/或蚀刻，全息曝光等手段形成的。单元202，203，204，205可以是由，例如一个或多个表面衍射光栅或由一个或多个体全息衍射光栅实现。
在一个实施例中，输入光IN1可以是基本上单色的或不同输入波长λ0。所有光束IN1，B1，B2，B3，B4，OUT1，OB3，AUX1可以具有相同的波长λ0。
衍射效率的空间分布可以通过选择微观衍射特征F的局部参数才进行控制。 可以通过控制出瞳单元204的微观衍射特征F的参数，以进一步提升输出光OUT1的强度分布均匀性。
所述显示设备500可以是一个虚拟现实器件500或增强现实设备500。显示设备500可以是近眼设备，也可以是可穿戴设备，例如耳机。器件500可以用于，例如头带，通过该头带可以将器件500佩戴在用户的头上。在使用过程中，器件500的衍射出瞳单元204被放置在用户的左眼5或右眼5前面。器件500可以将输出光OUT1投射到用户的眼睛5中。在一个实施例中，设备500可以包括两个引擎10和/或两个扩瞳器件2以显示立体图像。对于增强现实器件500，观看者不但可以看到所述扩瞳器件2显示的虚拟图像外，还可以看到真实的物体和/或环境。引擎10可以生成静止图像和/或视频。引擎10可以从数字图像生成真实的主图像IMG0。引擎10可以从互联网服务器或从智能手机接收一个或多个数字图像。器件500可以是智能手机。显示的图像人可能会看到，所显示的图像也可以，例如由动物或机器(可以包括例如照相机)观看
最后应说明的是：以上所述仅为本发明的优选实施例而已，并不用于限制本发明，尽管参照前述实施例对本发明进行了详细的说明，对于本领域的技术人员来说，其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分技术特征进行等同替换。凡在本发明的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。

Claims (10)

  1. 一种光学器件(2)，其特征在于，包括：
    波导板(201)，其包括：
    衍射入瞳单元(202)，其通过衍射所述输入光(IN1)而形成第一传导光(B1)和第二传导光(B2)；
    衍射扩瞳单元(203)通过衍射所述第一传导光(B1)以形成第三传导光(B3)；
    衍射出瞳单元(204)通过衍射所述第三传导光(B3)形成第一输出光(OB3)；
    旁路单元(205)，其通过使第二传导光(B2)衍射而形成第四传导光(B4)；
    其中，第一传导光(B1)沿第一方向(301)传播，第二传导光(B2)沿第二方向(302)传播，并且第一方向(301)和所述第二方向之间(302)的夹角(12)在60°至120°的范围内；
    其中衍射出瞳单元(204)包括一个或多个增强区域(401，402)，以通过衍射第四传导光(B4)形成辅助输出光(AUX3)。
  2. 根据权利要求1所述的光学器件，其特征在于：所述衍射出瞳单元(204)包括一个或多个所述区域(400)，所述区域(400)不使第四传导光(B4)从波导板(201)中衍射出来。
  3. 根据权利要求2所述的光学器件，其特征在于：所述第三传导的光(B3)的传播方向是第三方向(303)且基本平行与所述第二方向(302)；其中所述第四传导光(B4)传播方向是在第四方向(304)，且基本平行与所述第一方向(301)。
  4. 根据权利要求3所述的光学器件，其特征在于：所述第一增强区域(401)通过使第三导光(B3)衍射而形成第一输出光(OB3)，同时通过衍射第四传导光(B4)以形成辅助输出光(AUX3)，并且通过将辅助输出光(AUX3)与第 一输出光(OB3)叠加来形成组合输出光(OUT1)。
  5. 根据权利要求4所述的光学器件，其特征在于：所述入瞳单元(202)和旁路单元(205)之间的距离(L14)是在输出耦合区域(204)高度(H3)的50％至80％范围内；所述第二传导的光的器件(B2)在入瞳单元(202)和扩瞳单元(203)之间，不与所述衍射出瞳单元(204)相互作用。
  6. 根据权利要求5所述的光学器件，其特征在于：所述输衍射出瞳单元(204)包括一个或多个基准区域(400)，它们不使第四传导光(B4)从波导板(201)中衍射出来，其中基准区域(400)的总面积在出瞳单元(204)面积的30％至95％。
  7. 根据权利要求6所述的光学器件，其特征在于：至少有一部分的所述第四传导的光(B4)从所述旁路单元(205)直接传播至第一增强区域(401)而不经过的基准区域(400)，不会使第四传导光(B4)从波导板(201)衍射。
  8. 一种显示设备(500)，其特征在于，包括光学引擎(10)以形成主图像并将主图像转换为多个输入光束(IN1)，该设备(500)包括权利要求1至7任意一项所述的光学器件(2)，通过衍射扩展输入光束(IN1)形成输出光束(OUT1)。
  9. 使用权利要求1所述的光学器件(2)来提供输出光(OUT1)的方法。
  10. 使用权利要求1所述的光学器件(2)来显示图像的方法。
PCT/CN2020/097051 2020-06-19 2020-06-19 一种光学器件、显示设备及其输出光和显示图像的方法 WO2021253385A1 (zh)

Priority Applications (3)

Application Number Priority Date Filing Date Title
PCT/CN2020/097051 WO2021253385A1 (zh) 2020-06-19 2020-06-19 一种光学器件、显示设备及其输出光和显示图像的方法
KR1020237002365A KR20230025022A (ko) 2020-06-19 2020-06-19 광학 디바이스, 표시 장치 및 이의 광 출력 및 이미지 표시 방법
EP20941252.7A EP4170412A4 (en) 2020-06-19 2020-06-19 OPTICAL DEVICE, DISPLAY DEVICE AND LIGHT OUTPUT AND IMAGE DISPLAY METHOD THEREFOR

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2020/097051 WO2021253385A1 (zh) 2020-06-19 2020-06-19 一种光学器件、显示设备及其输出光和显示图像的方法

Publications (1)

Publication Number Publication Date
WO2021253385A1 true WO2021253385A1 (zh) 2021-12-23

Family

ID=79268935

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/097051 WO2021253385A1 (zh) 2020-06-19 2020-06-19 一种光学器件、显示设备及其输出光和显示图像的方法

Country Status (3)

Country Link
EP (1) EP4170412A4 (zh)
KR (1) KR20230025022A (zh)
WO (1) WO2021253385A1 (zh)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20170102543A1 (en) * 2015-10-07 2017-04-13 Tuomas Vallius Diffractive optical element with integrated in-coupling, exit pupil expansion, and out-coupling
CN111025657A (zh) * 2019-12-31 2020-04-17 瑞声通讯科技(常州)有限公司 近眼显示装置
CN111240015A (zh) * 2020-01-17 2020-06-05 北京理工大学 双侧对射出光均匀的衍射波导
CN210720886U (zh) * 2019-11-18 2020-06-09 苏州苏大维格科技集团股份有限公司 用于增强现实显示的装置和系统
CN210720885U (zh) * 2019-11-18 2020-06-09 苏州苏大维格科技集团股份有限公司 用于增强现实显示的装置和用于实现增强现实显示的系统

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NZ730509A (en) * 2014-09-29 2018-08-31 Magic Leap Inc Architectures and methods for outputting different wavelength light out of waveguides
CN111123523B (zh) * 2020-01-17 2020-10-27 北京枭龙科技有限公司 无显示暗带的衍射波导
CN111123524A (zh) * 2020-01-17 2020-05-08 北京枭龙科技有限公司 能扩瞳且出光均匀的衍射波导

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20170102543A1 (en) * 2015-10-07 2017-04-13 Tuomas Vallius Diffractive optical element with integrated in-coupling, exit pupil expansion, and out-coupling
CN210720886U (zh) * 2019-11-18 2020-06-09 苏州苏大维格科技集团股份有限公司 用于增强现实显示的装置和系统
CN210720885U (zh) * 2019-11-18 2020-06-09 苏州苏大维格科技集团股份有限公司 用于增强现实显示的装置和用于实现增强现实显示的系统
CN111025657A (zh) * 2019-12-31 2020-04-17 瑞声通讯科技(常州)有限公司 近眼显示装置
CN111240015A (zh) * 2020-01-17 2020-06-05 北京理工大学 双侧对射出光均匀的衍射波导

Also Published As

Publication number Publication date
KR20230025022A (ko) 2023-02-21
EP4170412A4 (en) 2023-08-16
EP4170412A1 (en) 2023-04-26

Similar Documents

Publication Publication Date Title
US11480722B2 (en) Optical expander device and its display device and method for outputting light and displaying image
CN112817153B (zh) 一种大视场角的光学扩瞳装置、显示装置及方法
JP6714797B2 (ja) 射出瞳を拡大する回折光導波路装置
CN109073884B (zh) 具有改进的强度分布的波导出射光瞳扩展器
US11119262B1 (en) Optical device, display device, and method for outputting light and displaying image thereof
US20170299864A1 (en) Waveguides with extended field of view
US20170235144A1 (en) Holographic see-through optical device, stereoscopic imaging system, and multimedia head mounted system
US11994684B2 (en) Image light guide with zoned diffractive optic
US11789261B2 (en) Optical expander device for displaying wide color image, display device thereof, and method for outputting light and displaying an image
US20230075954A1 (en) Optical expander device
EP2153266A1 (en) A diffractive beam expander and a virtual display based on a diffractive beam expander
CN111880304A (zh) 光学扩瞳装置和显示设备及其输出光束和显示图像的方法
CN113219671A (zh) 光学装置和显示设备
WO2022115580A1 (en) Image light guide with zoned diffractive optic
US20230266599A1 (en) Image light guide with compound diffractive optical element and the head-mounted display made therewith
US20220107501A1 (en) Near-eye display device, augented reality glasses including same, and operating method therefor
JP2023514761A (ja) 拡張現実画像を表示するための装置および該装置を含むシステム
WO2023169502A1 (zh) 一种大视场角的光学扩瞳装置、显示装置及方法
CN212647158U (zh) 光学扩瞳装置及其显示设备
WO2021253385A1 (zh) 一种光学器件、显示设备及其输出光和显示图像的方法
US20230324595A1 (en) Low distortion imaging through a c-shape flat optical architecture
CN213544957U (zh) 一种光学器件及其显示设备
US20230296883A1 (en) Optical expander apparatus of large field of view and display apparatus
CN218122364U (zh) 光学装置和显示设备
CN219737894U (zh) 一种增大视场角的光波导显示装置及ar显示设备

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20941252

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 20237002365

Country of ref document: KR

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 2020941252

Country of ref document: EP

Effective date: 20230118