Image projection device

Abstract

To provide an image projection device capable of appropriately branching multiple pieces of image light and capable of reducing weight and improving a degree of freedom in designing.SOLUTION: An image projection device for projecting image light to a display section for displaying a virtual image includes: an image display section (12) for applying image light for a short distance from a near display area (12b) and applying image light for a long distance from a far display area (12a); a first plane mirror (13) for reflecting image light for a long distance; a second plane mirror (14) for reflecting the image light for a long distance reflected by the first plane mirror (13); and a projection optical section for irradiating a display section with the image light for a short distance entering from the near display area (12b) and the image light for a long distance entering from the second plane mirror (14).SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an image projection device, and more particularly to an image projection device that irradiates a projection image onto a display unit for displaying a virtual image.

Background Art

[0002] Conventionally, as a device for displaying various information in a vehicle, an instrument panel that turns on and displays icons has been used. In addition, with the increase in the amount of information to be displayed, it has also been proposed to embed an image display device in the instrument panel or to configure the entire instrument panel with an image display device.

[0003] However, since the instrument panel is located below the front glass (windshield) of the vehicle, it is not preferable because the driver needs to move the line of sight downward during driving in order to visually recognize the information displayed on the instrument panel. Therefore, a head-up display (hereinafter referred to as HUD: Head Up Display) that projects an image onto the front glass so that the driver can read the information when visually recognizing the front of the vehicle has also been proposed (see, for example, Patent Documents 1 and 2).

[0004] In such a conventional image projection device, image light is irradiated from an image irradiation unit onto the windshield (display unit) of the vehicle, and the driver can visually recognize by superimposing the image light reflected by the windshield and the background in front of the vehicle. In addition, it has also been proposed to irradiate a plurality of image lights to form a plurality of virtual images at different distances from the windshield.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] In a conventional image projection device, a plurality of image lights irradiated from a liquid crystal display device or the like are branched using an optical member, and the imaging position of a virtual image is made different depending on the difference in the path after the branching of the image lights. As the optical member for branching the image lights, it is also assumed to use a reflection prism or the like, but in order to branch the image lights irradiated from a large-area display region, it is necessary to thicken the reflection prism, and there are problems in terms of moldability and weight reduction. Further, since the refractive index of the material constituting the reflection prism is larger than that of air, there are restrictions in terms of the optical path difference of the light propagating in the reflection prism and the angle of the reflection surface, etc., and there is a problem that the degree of design freedom is low. In particular, depending on the angle at which the image light is incident on the reflection surface, there is also a possibility that aberration occurs in the projected virtual image, and there is also a problem that the visibility of the virtual image is reduced.

[0007] Therefore, the present invention has been made in view of the above conventional problems, and an object thereof is to provide an image projection device capable of appropriately branching a plurality of image lights and achieving weight reduction and an improvement in the degree of design freedom.

Means for Solving the Problems

[0008] In order to solve the above problems, an image projection device of the present invention is an image projection device that projects image light onto a display unit for displaying a virtual image, and includes an image display unit that irradiates near-field image light from a near-field display region and far-field image light from a far-field display region, a first planar mirror that reflects the far-field image light, a second planar mirror that reflects the far-field image light reflected by the first planar mirror, and a projection optical unit that irradiates the display unit with the near-field image light incident from the near-field display region and the far-field image light incident from the second planar mirror.

[0009] In such an image projection apparatus of the present invention, the far-field image light irradiated from the far-field display area is reflected by the first planar mirror and the second planar mirror, and the near-field image light is irradiated from the near-field display area. By irradiating the display unit with the far-field image light and the near-field image light from the projection optical unit, a plurality of image lights can be appropriately branched, and it is possible to reduce the weight and improve the design freedom.

[0010] Further, in one aspect of the present invention, the first planar mirror is provided so as to be inclined by a first angle θ1 with respect to a virtual plane perpendicular to the reference ray of the far-field image light directed toward the display unit, and the second planar mirror is provided so as to be inclined by a second angle θ2 with respect to the virtual plane, and the difference between the first angle θ1 and the second angle θ2 is in the range of -5 degrees or more and +5 degrees or less.

[0011] Further, in one aspect of the present invention, the first angle θ1 is in the range of -60 degrees or more and -45 degrees or less.

[0012] Further, in one aspect of the present invention, the far-field image light includes polarized light in a predetermined direction, and the second planar mirror includes a polarization reflection unit that reflects the polarized light in the predetermined direction and transmits the polarized light in a direction intersecting the predetermined direction.

[0013] Further, in one aspect of the present invention, the main irradiation direction of the near-field image light is different from the main irradiation direction of the far-field image light.

[0014] Further, in one aspect of the present invention, the projection optical unit includes a primary mirror that reflects the near-field image light and the far-field image light.

Advantages of the Invention

[0015] In the present invention, it is possible to provide an image projection apparatus capable of appropriately branching a plurality of image lights and achieving weight reduction and improvement of design freedom.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0017] (First Embodiment) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The same or equivalent components, members, and processes shown in each drawing are denoted by the same reference numerals, and repeated explanations will be omitted as appropriate. FIG. 1 is a schematic diagram for explaining the projection of virtual images P1 and P2 using the image projection apparatus 100 according to the present embodiment. As shown in FIG. 1, the image projection apparatus 100 includes an image irradiation unit 10, a primary mirror 20, and a secondary mirror 30. In FIG. 1, the direction perpendicular to the paper surface is defined as the x - axis direction, the vertical direction is defined as the y - axis direction, and the horizontal direction is defined as the z - axis direction. Here, the x - axis direction corresponds to the left - right direction (width direction) of the vehicle on which the image projection apparatus 100 is mounted, the y - axis direction corresponds to the up - down direction (vertical direction), and the z - axis direction corresponds to the front - rear direction.

[0018] As shown in FIG. 1, the image light projected from the image projection apparatus 100 is reflected by the windshield (display unit) WS and irradiated to the driver's viewpoint position. The driver visually recognizes the virtual images P1 and P2 formed on the extension of the optical path (broken - line direction) where the image light is incident. In the present embodiment, an example in which the image projection apparatus 100 projects image display light and two virtual images P1 and P2 are formed is shown, but the number of virtual images is not limited.

[0019] In the image projection device 100 of this embodiment, far-field image light and near-field image light are irradiated from the image irradiation unit 10, and are respectively imaged as virtual images P1 and P2. The dashed line shown in FIG. 1 schematically shows the path (reference ray) of the center position of the far-field image light, and the one-dot chain line schematically shows the path (reference ray) of the center position of the near-field image light. Examples of the far-field image projected by the far-field image light include auxiliary information related to driving such as an attention-arousing image and emergency information. Examples of the near-field image projected by the near-field image light include a speed and volume indicator, a traveling direction guide, and the like.

[0020] As shown in FIG. 1, the far-field image light and the near-field image light irradiated from the image irradiation unit 10 are reflected by the primary mirror 20, the secondary mirror 30, and the windshield WS and reach the viewpoint 40. At this time, the trajectory of the light reaching the viewpoint 40 from the direction of visually recognizing the virtual images P1 and P2 is defined as the reference ray. In other words, this reference ray can be regarded as being substantially the same as the trajectory when the light irradiated from the center of the effective area where the light is emitted in the image irradiation unit 10 reaches the viewpoint 40. The actual image light is irradiated from the image irradiation unit 10 over a predetermined area, and is light in which the light beam spreads from each position on the display surface, and is condensed or enlarged by the optical power of the reflecting surfaces of the primary mirror 20 and the secondary mirror 30. Therefore, the reference ray shown in FIG. 1 does not indicate the path of the irradiation light in the entire area of the image irradiation unit 10.

[0021] The image irradiation unit 10 is a part that irradiates image light including image information when a signal including image information is supplied from an information processing unit (not shown). Details of the image irradiation unit 10 will be described later. The image light irradiated from the image irradiation unit 10 enters the primary mirror 20. The specific configuration of the image irradiation unit 10 is not limited, and for example, a conventionally known one such as a liquid crystal display device, an organic EL display device, or a combination of a laser light source and an optical modulation element can be used. In the example shown in FIG. 1, a device that irradiates light with a light emitting diode (LED: Light Emitting Diode) from the back side of the liquid crystal display device is used.

[0022] The primary mirror 20 is an optical member onto which the image light irradiated from the image irradiation unit 10 is incident and which reflects the light in the direction of the secondary mirror 30. In the example shown in FIG. 1, the primary mirror 20 is a free-form mirror with an optical design necessary for projecting the image light as virtual images P1 and P2. Although details of the reflecting surface of the primary mirror 20 will be described later, it has a saddle shape that is concave in the y-axis direction (first direction) and convex in the x-axis direction (second direction). Therefore, the reflecting surface of the primary mirror 20 gives positive optical power to the image light in the height direction and negative optical power in the width direction. Also, the reflecting surface of the primary mirror 20 is set such that only the y-axis component is intermediate-imaged before reaching the secondary mirror 30.

[0023] The secondary mirror 30 is an optical member onto which the image light reflected by the primary mirror 20 is incident and which reflects the light in the direction of the windshield WS. In the example shown in FIG. 1, the secondary mirror 30 is a free-form mirror with a concave shape having an optical design necessary for projecting the image light as virtual images P1 and P2. The reflecting surface of the secondary mirror 30 has different focal lengths in the x-axis component and the y-axis component in the plane, and is set such that the x-axis component and the y-axis component of the irradiated light are imaged at the same position after being reflected by the secondary mirror 30. Here, the combination of the primary mirror 20 and the secondary mirror 30 constitutes the projection optical unit in the present invention for irradiating the windshield WS with near-field image light and far-field image light.

[0024] The windshield WS is provided in front of the driver's seat of the vehicle and functions as an optical member that reflects the image light incident from the secondary mirror 30 in the direction of the viewing point 40 on the inner surface of the vehicle and transmits the light from the outside of the vehicle in the direction of the viewing point 40. Therefore, the windshield WS corresponds to the display unit in the present invention. Although an example using the windshield WS as the display unit is shown here, a combiner may be prepared as the display unit separately from the windshield WS, and the light from the secondary mirror 30 may be reflected in the direction of the viewing point 40. Also, it is not limited to being located in front of the vehicle, and it may be arranged on the side or rear as long as it projects an image onto the viewing point 40 of the passenger.

[0025] The viewing point 40 is the eyes (eyeboxes) of the driver or passenger of the vehicle. When image light enters the eyebox and reaches the retina, the driver or passenger visually recognizes the formed virtual images P1 and P2.

[0026] The virtual images P1 and P2 are displayed as if they were formed in space when the image light reflected by the windshield WS reaches the viewing point (eyebox) 40 of the driver or the like. The positions where the virtual images P1 and P2 are formed are determined by the spreading angle when the light irradiated from the image irradiation unit 10 travels in the direction of the viewing point 40 after being reflected by the primary mirror 20 and the secondary mirror 30. At this time, the driver or passenger at the viewing point 40 recognizes that the virtual images P1 and P2 exist at imaging positions farther than the windshield WS.

[0027] FIG. 2 is a schematic diagram showing a configuration example of the image irradiation unit 10. As shown in FIG. 2, the image irradiation unit 10 includes a light source unit 11, an image display unit 12, a first plane mirror 13, and a second plane mirror 14. The image display unit 12 includes a far display region 12a and a near display region 12b. The dashed arrows shown in FIG. 2 schematically show the path (reference ray) of the center position of the far image light, and the dashed-dotted arrows schematically show the path (reference ray) of the center position of the near image light.

[0028] The light source unit 11 is a part that irradiates irradiation light to the image display unit 12. In the example shown in FIG. 2, the light source unit 11 is arranged on the back side of the transmissive image display unit 12, and a configuration is shown in which the irradiation light passes through the image display unit 12. However, it is also possible to irradiate the irradiation light from the display surface side using a reflective image display unit 12. The specific configuration of the light source unit 11 is not limited, and a light emitting diode (LED: Light Emitting Diode) or a laser light source can be used. Also, when an organic EL display device is used as the image display unit 12, the light source unit 11 and the image display unit 12 are integrally configured.

[0029] The image display unit 12 is a part that displays a projection image based on the image information from the control unit. The specific configuration of the image display unit 12 is not limited, and for example, a conventionally known device such as a liquid crystal display device, an organic EL display device, or a light modulation element can be used. In the example shown in FIG. 2, a liquid crystal display device is used as the image display unit 12. As will be described later, the image display unit 12 includes a far - distance display area 12a and a near - distance display area 12b that display a far - distance image and a near - distance image, respectively. The far - distance image displayed in the far - distance display area 12a is irradiated as far - distance image light, and the near - distance image displayed in the near - distance display area 12b is irradiated as near - distance image light. Here, the far - distance display area 12a and the near - distance display area 12b may be configured by different display devices, but it is preferable to use a single display device divided into two areas.

[0030] The first planar mirror 13 is an optical member having a flat reflecting surface. The reflecting surface of the first planar mirror 13 is arranged at a position where the far - distance image light irradiated from the far - distance display area 12a is incident. Also, the reflecting surface of the first planar mirror 13 is arranged to be inclined by a predetermined angle with respect to the far - distance display area 12a, and reflects the incident far - distance image light in the direction of the second planar mirror 14.

[0031] The second planar mirror 14 is an optical member having a flat reflecting surface. The reflecting surface of the second planar mirror 14 is arranged at a position where the far - distance image light reflected by the first planar mirror 13 is incident. Also, the reflecting surface of the second planar mirror 14 is arranged to be inclined by a predetermined angle with respect to the image display unit 12, and reflects the incident far - distance image light in the direction of the primary mirror 20.

[0032] FIG. 3 is a schematic perspective view for explaining the paths of the far - field image light L1 and the near - field image light L2 irradiated from the image irradiation unit 10. In the example shown in FIG. 3, in the image display unit 12, the far - field display area 12a and the near - field display area 12b are arranged side by side in the parallel direction. Assuming that the direction orthogonal to the parallel direction of the image display unit 12 is the width direction, the far - field image light L1 and the near - field image light L2 are irradiated while being inclined by a predetermined angle in the width direction with respect to the display surface of the image display unit 12. Therefore, the first planar mirror 13 and the second planar mirror 14 are arranged at positions shifted in the width direction with respect to the image display unit 12.

[0033] As shown in FIGS. 2 and 3, the far - field image light L1 irradiated from the far - field display area 12a enters the first planar mirror 13 and is reflected, and then travels in the direction of the second planar mirror 14. The far - field image light L1 that reaches the second planar mirror 14 is reflected again and reaches the primary mirror 20. Also, the first planar mirror 13 and the second planar mirror 14 are not arranged on the path of the near - field image light L2 irradiated from the near - field display area 12b. Therefore, the near - field image light L2 irradiated from the near - field display area 12b travels through the space between the first planar mirror 13 and the second planar mirror 14 and reaches the primary mirror 20.

[0034] As shown in FIGS. 2 and 3, the near - field image light L2 is directly irradiated onto the primary mirror 20, while the far - field image light L1 is reflected by the first planar mirror 13 and the second planar mirror 14 and then irradiated onto the primary mirror 20. As a result, an optical distance difference occurs between the near - field image light L2 and the far - field image light L1 until they reach the primary mirror 20 by the distance W in the parallel direction of the image display unit 12. Also, on the reflection surface of the primary mirror 20, the regions where the far - field image light L1 and the near - field image light L2 reach are different, and the paths of the far - field image light L1 and the near - field image light L2 reflected by the primary mirror 20 are also different. Due to this difference in optical distance and path, the distances and imaging positions of the virtual images P1, P2 from the windshield WS are different.

[0035] When propagating the far-field image light L1 in a substance with a refractive index n using a prism or the like, the optical distance difference generated between the far-field image light L1 and the near-field image light L2 is nW, which is the product of the distance W and the refractive index n. Since the refractive index of the substance constituting the prism is greater than 1, it is difficult to make the optical distance difference generated between the far-field image light L1 and the near-field image light L2 smaller than nW.

[0036] By adjusting the reflection surface angle of the prism to reduce the distance between the two reflection surfaces of the prism, it is possible to make the optical distance difference smaller than nW. However, there is also a limit to the angle of the reflection surface for the far-field image light L1 to reach the second plane mirror 14 from the first plane mirror 13, and the design freedom is low. In addition, since aberration occurs depending on the incident angle of the far-field image light L1 on the reflection surface of the prism, it is also difficult to improve the quality of the virtual image P1.

[0037] In the image projection apparatus 100 of the present embodiment, the far-field image light L1 propagates between the first plane mirror 13 and the second plane mirror 14 in air with a refractive index of 1. Therefore, the optical distance difference generated between the far-field image light L1 and the near-field image light L2 is W, which is the product of the distance W in the parallel direction of the image display unit 12 and the refractive index 1. Thus, when using the first plane mirror 13 and the second plane mirror 14, the optical distance difference generated between the far-field image light L1 and the near-field image light L2 can be reduced to about W. In addition, by arranging the second plane mirror 14 at a position away from the image display unit 12 in the parallel direction, the optical distance difference can be made larger than W.

[0038] FIG. 4 is a schematic diagram for explaining the angles of the first plane mirror 13 and the second plane mirror 14 in the image irradiation unit 10. In the present embodiment, the irradiation angle of the image light from the image display unit 12 is different for each region. The far-field image light L1 irradiated from the far-field display region 12a is irradiated at an angle α1, and the near-field image light L2 irradiated from the near-field display region 12b is irradiated at an angle α2. Therefore, the main irradiation direction of the near-field image light L2 from the image display unit 12 is different from the main irradiation direction of the far-field image light L1.

[0039] Here, assume a virtual plane perpendicular to the reference light ray of the distant image light directed toward the windshield WS, and set the clockwise direction in the figure as the positive angular direction and the counterclockwise direction as the negative angular direction. The first planar mirror 13 is disposed at an angle θ1 with respect to the virtual plane, and the second planar mirror 14 is disposed at an angle θ2 with respect to the virtual plane. The rectangle shown by the two-dot chain line in FIG. 4 indicates a virtual first planar mirror 13' disposed in parallel with the second planar mirror 14. Therefore, the reflecting surfaces of the first planar mirror 13 and the second planar mirror 14 are provided with an angular difference of Δθ = θ1 - θ2. Here, the angles θ1 and θ2 respectively correspond to the first angle and the second angle in the present invention.

[0040] As described above, in the present embodiment, the first planar mirror 13 and the second planar mirror 14 are used to create an optical distance difference between the distant image light L1 and the near image light L2, and there is no need to reduce the angle θ1 to bring the first planar mirror 13 closer to the distant display area 12a. Therefore, the irradiation angle α1 of the distant image light L1 irradiated from the distant display area 12a can be made closer to 90 degrees. At this time, the angle θ1 of the first planar mirror 13 is preferably in the range of -60 degrees or more and -45 degrees or less. By setting the angle θ1 of the first planar mirror 13 within this angular range, it is possible to suppress the occurrence of aberration in the imaging of the virtual image P1 with the distant image light L1.

[0041] Also, the difference Δθ between the angle θ1 and the angle θ2 is preferably in the range of -10 degrees or more and +10 degrees or less, and more preferably in the range of -5 degrees or more and +5 degrees or less. By setting Δθ within this angular range, it is possible to suppress spherical aberration and image plane tilt and project a virtual image. In addition, since the first planar mirror 13 and the second planar mirror 14 are used, the optical path difference is smaller compared to the case of using a prism, and the design freedom can be improved.

[0042] As described above, in the image projection apparatus 100 of the present embodiment, by reflecting the far-field image light L1 irradiated from the far-field display area 12a with the first flat mirror 13 and the second flat mirror 14, a plurality of image lights can be appropriately branched, and it is possible to achieve weight reduction and an improvement in the degree of design freedom. (Second Embodiment)

[0043] Next, a second embodiment of the present invention will be described with reference to FIG. 5. Descriptions of the contents overlapping with the first embodiment will be omitted. FIG. 5 is a schematic diagram for explaining a configuration example of the image irradiation unit 10 in the present embodiment and the angles of the first flat mirror 13 and the second flat mirror 14. In the present embodiment, it is different from the first embodiment in that a polarization reflection unit 15 is provided on the reflection surface of the second flat mirror 14.

[0044] As shown in FIG. 5, the image irradiation unit 10 in the image projection apparatus 100 of the present embodiment includes an image display unit 12, a first flat mirror 13, a second flat mirror 14, and a polarization reflection unit 15. Further, the image display unit 12 includes a far-field display area 12a and a near-field display area 12b. The second flat mirror 14 may be made of a material that transmits light or a material that blocks light.

[0045] The polarization reflection unit 15 is an optical member that reflects polarized light in a predetermined direction and transmits polarized light in a direction intersecting the predetermined direction. In the example shown in FIG. 5, an example in which the polarization reflection unit 15 is attached to the reflection surface of the second flat mirror 14 is shown, but the second flat mirror 14 itself may be configured as a self-supporting plate-shaped polarization reflection unit 15. The polarization direction reflected by the polarization reflection unit 15 is set to the polarization direction of the image light irradiated from the image display unit 12. As a result, the far-field image light L1 irradiated from the far-field display area 12a is reflected by the first flat mirror 13 and the polarization reflection unit 15 and reaches the primary mirror 20.

[0046] The arrow indicated by the solid line in FIG. 5 schematically shows the external light LO that has reached from outside the image projection device 100. The image projection device 100 is mounted on a vehicle or the like as shown in FIG. 1, and irradiates image light toward the windshield WS. At this time, part of the external light LO such as sunlight incident from above the vehicle is reflected by the secondary mirror 30 and the primary mirror 20 and reaches the image irradiation unit 10. Such external light LO may increase the surface temperature of the image display unit 12 and cause deterioration. In particular, the external light LO that has reached the far - away display area 12a is condensed by the secondary mirror 30 and the primary mirror 20, so it is likely to cause temperature rise and deterioration.

[0047] Here, the external light LO is unpolarized light and includes polarized light reflected by the polarization reflection unit 15 and polarized light transmitted therethrough. Therefore, among the external light LO that has reached the polarization reflection unit 15, the polarization component in the above - mentioned predetermined direction is reflected in the direction of the first plane mirror 13, while the polarization component orthogonal to the predetermined direction passes through the polarization reflection unit 15. When the second plane mirror 14 is made of a material that blocks light, the external light LO that has passed through the polarization reflection unit 15 is absorbed by the second plane mirror 14. When the second plane mirror 14 is made of a material that transmits light, the external light LO that has passed through the polarization reflection unit 15 is absorbed by other members of the image projection device 100.

[0048] Therefore, the energy of the external light LO that reaches the far - away display area 12a becomes half of the external light LO that has entered the polarization reflection unit 15, and the temperature rise and deterioration of the far - away display area 12a can be suppressed.

[0049] The present invention is not limited to the above - described embodiments, and various modifications are possible within the scope shown in the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

Explanation of reference numerals

[0050] 100…Image projection device 10…Image irradiation unit 20…Primary mirror 30…Secondary mirror 40…Viewpoint 11…Light source unit 12…Image display unit 12a…Distant display area 12b…Near display area 13…First plane mirror 14…Second plane mirror 15…Polarization reflection unit

Claims

1. An image projection device that projects image light onto a display unit for displaying a virtual image, an image display unit that irradiates near image light from a near display region and far image light from a far display region; a first plane mirror that reflects the far-field image light; a second plane mirror that reflects the far-distance image light reflected by the first plane mirror; An image projection device comprising: a projection optical unit that irradiates the near image light incident from the near display area and the far image light incident from the second plane mirror onto the display unit.

2. 2. The image projection device according to claim 1, the first plane mirror is provided so as to be inclined at a first angle θ1 with respect to a virtual plane perpendicular to a reference ray of the far-distance image light directed toward the display unit, the second plane mirror is inclined at a second angle θ2 with respect to the virtual plane, An image projection device, characterized in that a difference between the first angle θ1 and the second angle θ2 is in a range of −5 degrees or more and +5 degrees or less.

3. 3. The image projection device according to claim 2, The image projection device, wherein the first angle θ1 is in the range of −60 degrees or more and −45 degrees or less.

4. 2. The image projection device according to claim 1, the far-field image light includes polarized light in a predetermined direction, The image projection device, wherein the second plane mirror includes a polarizing reflecting portion that reflects polarized light in the predetermined direction and transmits polarized light in a direction intersecting the predetermined direction.

5. 2. The image projection device according to claim 1, 13. An image projection device, comprising: a projection lens for projecting an image of a near object; and a projection lens for projecting an image of a far object, the projection lens being disposed in a direction substantially parallel to the projection lens.

6. 6. The image projection device according to claim 1, The image projection device according to claim 1, wherein the projection optical unit includes a primary mirror that reflects the near image light and the far image light.

Images