JP2018040842A - Head-up display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an HUD device that is high in visibility of virtual images.SOLUTION: An HUD device 100 is configured to be loaded in a vehicle where an eyellipse ELP is specifiable; project display light toward a reflection part 3a of a windshield 3; make the display light reach inside the eyellipse ELP as making the display light reflect upon the reflection part 3a; and thereby display a virtual image visible from inside the eyellipse ELP. The HUD device 100 comprises: a laser light source that emits a laser flux; a scanning unit 20 that deflects the laser flux at a deflection point TP to scan the laser flux; and a curved surface array member 40 that has a plurality of optical curved surfaces arrayed in a grid-shape, in which the laser flux scanned by the scan unit is incident and thereby an image is drawn, and ejects the laser flux as display light as enlarging a spread angle of the laser flux due to each optical curved surface. A conjugate point having an optical conjugation with the deflection point TP is located at or farther than the most distant part Emd relative to the reflection part 3a.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a head-up display device (hereinafter abbreviated as a HUD device) that is mounted on a vehicle and displays a virtual image.

  Conventionally, a HUD device mounted on a vehicle and displaying a virtual image is known. The HUD device disclosed in Patent Document 1 includes a laser light source unit that emits a laser beam, a scanning unit that scans the laser beam by deflecting the laser beam at a deflection point, and a laser beam that is scanned by the scanning unit is incident By doing so, it has a screen on which an image is drawn.

  Further, in the HUD device of Patent Document 1, the conjugate point that is optically conjugate with the deflection point of the scanning unit is set to the position of the eye of the vehicle occupant. Thereby, the brightness nonuniformity of a virtual image is suppressed. Specifically, Patent Document 1 discloses that a conjugate relationship is maintained by detecting the position of an eye with a camera and adjusting the position of a scanning unit.

  On the other hand, the HUD device disclosed in Patent Document 2 employs a curved surface array member in which a plurality of optical curved surfaces are arrayed in a lattice shape as the screen in Patent Document 1. Due to such an optical curved surface, the laser beam is emitted as display light while expanding the divergence angle.

JP 2015-176130 A JP 2010-145924 A

  Now, in the HUD device adopting a curved surface array member in which a plurality of optical curved surfaces are arrayed, the present inventors suppress the luminance unevenness of the virtual image without always adjusting the position of the scanning unit in order to simplify the device. Possible placement of conjugate points was examined. Here, in a curved surface array member in which a plurality of optical curved surfaces are arrayed in a lattice shape, diffraction occurs in a laser beam emitted as display light. Due to the diffracted light of each order, there is a possibility that the deflection point is formed as a plurality of real images on the occupant's eyes. Such a plurality of real images can be recognized as luminance unevenness in the virtual image.

  On the other hand, when the conjugate point coincides with the position of the occupant's eye, the deflection point is not imaged on the occupant's eye, and the occupant is difficult to recognize the occurrence of diffraction. However, in actuality, the position of the eye may move to, for example, the range of the eyelip, for example, when the occupant moves his head. Therefore, even if the conjugate point is located at the center of the eye, the positional relationship between the conjugate point and the eye changes according to the movement of the eye position, and the deflection point is imaged on the eye. Or not, it can be recognized as luminance unevenness of the virtual image. There is a concern that the visibility of the virtual image is thus lowered.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a HUD device with high visibility of a virtual image.

The present invention is mounted on a vehicle (1) that can define an iris (ELP), projects display light toward the reflecting portion (3a) of the projection member (3), and reflects the display light at the reflecting portion. A head-up display device that displays a virtual image (VI) that can be visually recognized from inside the eyelips by reaching inside the eyelips,
A laser light source section (10) for emitting a laser beam;
A scanning unit (20) for scanning the laser beam by deflecting the laser beam at a deflection point (TP);
A plurality of optical curved surfaces (42, 242) are arranged in a lattice pattern, and an image is drawn by the incidence of the laser beam scanned by the scanning unit, and the optical curved surface is displayed while increasing the divergence angle of the laser beam. A curved array member (40, 240) that emits light,
If the farthest part (Emd) that is the farthest from the reflection part of the Ilipus is defined,
A conjugate point (CP) optically conjugate with the deflection point is located farther than the farthest portion with respect to the reflecting portion.

  According to such an invention, the conjugate point that is optically conjugate with the deflection point is located farther than the farthest portion with respect to the reflecting portion. Therefore, even if diffraction occurs in the laser light beam emitted as display light in the optical curved surface arrangement unit in which a plurality of optical curved surfaces are arranged in a lattice shape, as long as the occupant's eyes exist in the eyelips, the occupant's eyes Regardless of the adjustment action, the deflection point is hardly imaged on the occupant's eyes. In this way, it is difficult to recognize the occurrence of diffraction by the occupant whose eyes are located in the eye lip, so that uneven brightness in the virtual image is suppressed. Therefore, it is possible to provide a HUD device with high visibility of a virtual image.

It is a schematic diagram which shows the mounting state to the vehicle of the HUD apparatus in 1st Embodiment. It is a schematic diagram which shows the optical system comprised by HUD in 1st Embodiment. It is a figure which expands and shows a part of FIG. It is a schematic diagram which shows the optical system from the laser light source part in 1st Embodiment to a curved surface arrangement | sequence member. It is a schematic diagram which shows the curved surface arrangement | sequence member in 1st Embodiment. It is a schematic diagram for demonstrating the conjugate point in 1st Embodiment. It is a figure corresponding to FIG. 2 in 2nd Embodiment. It is a figure which expands and shows a part of FIG. It is a figure corresponding to FIG. 5 in 2nd Embodiment. It is a figure corresponding to FIG. 2 in 3rd Embodiment. FIG. 10 is a diagram corresponding to FIG. 9 in Modification 1; FIG. 10 is a diagram corresponding to FIG. 9 in an example of Modification 2. FIG. 10 is a diagram corresponding to FIG. 9 in another example of Modification 2. It is a figure corresponding to FIG. 9 in an example among the modifications 3. FIG. It is a figure corresponding to FIG. 9 in another example among the modifications 3. It is a figure corresponding to FIG. 5 in the modification 4. FIG. 10 is a diagram corresponding to FIG. 5 in Modification 5.

  Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. In addition, the overlapping description may be abbreviate | omitted by attaching | subjecting the same code | symbol to the corresponding component in each embodiment. When only a part of the configuration is described in each embodiment, the configuration of the other embodiment described above can be applied to the other part of the configuration. In addition, not only combinations of configurations explicitly described in the description of each embodiment, but also the configurations of a plurality of embodiments can be partially combined even if they are not explicitly specified unless there is a problem with the combination. .

(First embodiment)
A HUD device 100 according to the first embodiment of the present invention shown in FIG. 1 is mounted on an instrument panel 2 of a vehicle 1. In the vehicle 1, an ellipsoidal eyelips ELP can be defined. The iris ELP is set based on an eye range that statistically represents the distribution of the positions of the eyes of the driver as an occupant of the vehicle 1 (see JIS D0021: 1998 for details). In addition, it is preferable to employ | adopt 90th percentile or more and 99th percentile or less eyelips, such as 90th percentile eyelips, 95th percentile eyelips, and 99th percentile eyelips, as eyelips ELP in this embodiment.

  The HUD device 100 projects the display light toward the reflecting portion 3a of the windshield 3 as a projection member of the vehicle 1. The projected display light is reflected by the reflecting portion 3a and then reaches the inside of the eyelips ELP. As a result, the HUD device 100 displays the virtual image VI that can be viewed from within the eyelips ELP. In other words, the display light is perceived as a virtual image VI by the driver whose eyes are located in the eyelips ELP in the vehicle 1. The driver can recognize various information displayed as the virtual image VI. Examples of various information displayed as the virtual image VI include vehicle state values such as vehicle speed and fuel remaining amount, or vehicle information such as road information and visibility assistance information.

  Here, the windshield 3 of the vehicle 1 is formed in a plate shape from translucent glass or synthetic resin. A portion of the windshield 3 onto which the display light is projected functions as a reflecting portion 3a that reflects the display light by being formed into a smooth concave surface or a planar shape on the indoor side. Here, the thickness of the reflecting portion 3a may be substantially constant, and the thickness increases toward the upper side of the vehicle, and may have a wedge shape in cross section. Moreover, as a projection member, instead of the windshield 3, a combiner that is separate from the vehicle 1 may be installed in the vehicle 1, and display light may be projected onto the combiner.

  In the present embodiment, the vehicle lower direction indicates a direction in which gravity is generated in the vehicle 1 on a horizontal plane. The upper side of the vehicle indicates the opposite direction of the lower side of the vehicle.

  2 to 4, the HUD device includes a laser light source unit 10, a scanning unit 20, an incident adjustment unit 30, a curved surface array member 40, and a light guide unit 50 in a housing 60.

  As shown in detail in FIG. 4, the laser light source unit 10 includes a plurality of laser oscillators 12a, 12b, and 12c, a plurality of collimating lenses 14a, 14b, and 14c, a folding mirror 16a, and a plurality of dichroic mirrors 16b and 16c. ing. In the present embodiment, three laser oscillators 12a to 12c and three collimating lenses 14a to 14c are provided.

  The three laser oscillators 12a to 12c oscillate laser beams having different wavelengths. Specifically, the laser oscillator 12a oscillates a green laser beam having a peak wavelength in the range of 490 to 530 nm, preferably 515 nm, for example. The laser oscillator 12b oscillates a blue laser beam having a peak wavelength in the range of 430 to 470 nm, preferably 450 nm, for example. The laser oscillator 12c oscillates a red laser beam having a peak wavelength in the range of 600 to 650 nm, preferably 640 nm, for example. Each laser beam emitted from each laser oscillator 12a-c is incident on a corresponding collimator lens 14a-c.

  The three collimating lenses 14a to 14c are arranged at predetermined intervals in the traveling direction of each laser beam with respect to the corresponding laser oscillators 12a to 12c, respectively. Each of the collimating lenses 14a to 14c refracts the laser beam of the corresponding color to make the laser beam approximately parallel.

  The folding mirror 16a is arranged at a predetermined interval in the traveling direction of the laser beam with respect to the collimating lens 14a, and reflects the laser beam transmitted through the collimating lens 14a.

  The two dichroic mirrors 16b to 16c are arranged at predetermined intervals in the traveling direction of each laser beam with respect to the corresponding collimating lenses 14b to 14c, respectively. Each of the dichroic mirrors 16b to 16c reflects a laser beam having a specific wavelength among the laser beams transmitted through the corresponding collimator lenses 14b to 14c, and transmits other laser beams. Specifically, the dichroic mirror 16b corresponding to the collimating lens 14b reflects a blue laser beam and transmits a green laser beam speed. The dichroic mirror 16c corresponding to the collimating lens 14c reflects the red laser beam and transmits the green and blue laser beams.

  Here, the dichroic mirror 16b is arranged at a predetermined interval in the traveling direction of the green laser light beam reflected by the folding mirror 16a. A dichroic mirror 16c is arranged at a predetermined interval in the traveling direction of the blue laser light beam reflected by the dichroic mirror 16b. With these arrangements, the green laser light beam reflected by the folding mirror 16a passes through the dichroic mirror 16b and is superimposed on the blue laser light beam after reflection by the dichroic mirror 16b. Further, the green laser beam and the blue laser beam are transmitted through the dichroic mirror 16c, and are superimposed on the red laser beam reflected by the dichroic mirror 16c.

  The laser oscillators 12 a to 12 c are electrically connected to the controller 18. Each of the laser oscillators 12a to 12c oscillates a laser beam in accordance with an electric signal from the controller 18. Various colors can be reproduced by adding and mixing the three color laser beams emitted from the laser oscillators 12a to 12c. In this way, the laser light source unit 10 emits the laser light beams having different wavelengths toward the scanning unit 20 in a state where the laser light beams are superposed on each other.

  As shown in detail in FIG. 4, the scanning unit 20 includes a scanning mirror 22. The scanning mirror 22 is a MEMS mirror configured using a micro electro mechanical system (MEMS) and capable of temporally scanning a laser beam. In the scanning mirror 22, a reflective surface 22 a is formed on the surface facing the dichroic mirror 16 c with a predetermined interval by metal deposition of aluminum or the like. The reflection surface 22a is rotatable around two rotation axes Ax and Ay substantially orthogonal along the reflection surface 22a.

  Such a scanning mirror 22 is electrically connected to the controller 18, and can turn the reflecting surface 22a by rotating according to the scanning signal. In this way, the scanning unit 20 controls the scanning mirror 22 by the controller 18 so that, in conjunction with the laser light source unit 10, for example, starting from the deflection point TP where the laser beam is incident on the reflection surface 22 a, In addition, it is possible to deflect the projection direction PD of the laser beam. The laser beam scanned by the scanning unit 20 by the deflection at the deflection point TP enters the incident adjustment unit 30.

  The incident adjustment unit 30 is disposed on the optical path between the scanning unit 20 and the curved surface array member 40 as shown in an enlarged view in FIG. The incident adjustment unit 30 includes a negative lens 32 and a projection mirror 34. The negative lens 32 is arranged closest to the scanning unit 20 on the optical path in the incident adjustment unit 30, and the projection mirror 34 is arranged closest to the curved surface array member 40 on the optical path in the incident adjustment unit 30. Here, the distance between the scanning unit 20 and the negative lens 32 is set to be smaller than the distance between the negative lens 32 and the projection mirror 34. The distance between the negative lens 32 and the projection mirror 34 is set to be smaller than the distance between the projection mirror 34 and the curved surface array member 40.

  The negative lens 32 is made of a synthetic resin or glass and has translucency. The negative lens 32 has, for example, a meniscus shape in which the incident-side refracting surface 32a is a smooth concave surface curved in a concave shape, and the exit-side refracting surface 32b is a smooth convex surface curved in a convex shape. The curvature of the incident side refracting surface 32a is set larger than the curvature of the exit side refracting surface 32b. The negative lens 32 is a negative optical element having a negative optical power.

  The projection mirror 34 is formed by vapor-depositing aluminum as the reflecting surface 34a on the surface of a base material made of synthetic resin or glass. The reflecting surface 34a is a smooth free-form surface that is concavely curved because the center is recessed. By such a reflecting surface 34a, the projection mirror 34 is a positive optical element having a positive optical power. The combined optical power of the negative lens 32 and the projection mirror 34 (that is, the optical power of the entire incident adjustment unit 30) is positive. The combined focal point of the negative lens 32 and the projection mirror 34 (that is, the focal point of the incident adjustment unit 30) is located farther on the optical path than the deflection point TP with respect to the incident adjustment unit 30.

  The laser beam scanned by the scanning unit 20 is incident on the incident adjustment unit 30. First, due to refraction at the negative lens 32, the laser beams corresponding to the respective projection directions PD temporarily increase the deviation in the traveling direction from each other. Next, the reflection of the projection mirror 34 causes the laser light beams corresponding to the respective projection directions PD to reduce the deviation in the traveling direction. In this way, the incident adjustment unit 30 adjusts the incident state of the laser light beam on the curved surface array member 40.

  The curved surface array member 40 is a reflective screen formed in a mirror array shape by, for example, depositing aluminum on the surface of a base material made of synthetic resin or glass. Specifically, as shown in FIG. 5, the curved array member 40 has a plurality of optical curved surfaces as aluminum metal deposition surfaces on the side facing the projection mirror 34 of the incident adjustment unit 30 and the magnifying mirror 52 of the light guide unit 50. 42 are arranged in a lattice pattern. In particular, in the present embodiment, each optical curved surface 42 is formed as a convex surface that is curved in a convex shape having a sufficiently larger curvature than each surface 32 a, 32 b, 34 a of the incident adjustment unit 30. In FIG. 5, the number of optical curved surfaces 42 is seven, but the number can be set as appropriate.

  In the present embodiment, the virtual reference surface BS, which is a virtual surface obtained by smoothly connecting the surface vertices 42a of the optical curved surfaces 42, is planar. In other words, each optical curved surface 42 is arranged along a planar virtual reference plane BS.

  In particular, as shown in FIG. 4, an image is drawn in the projection area PA of the curved surface array member 40 by the incidence of the laser light beam scanned by the scanning unit 20. Specifically, the scanning unit 20 is sequentially scanned along the plurality of scanning lines SL under the control of the controller 18. As a result, an image is drawn by intermittently irradiating the laser beam with a pulse while moving the position where the laser beam is incident in the projection area PA. An image drawn by projection onto the projection area PA is drawn, for example, as 60 frames per second as an image having 480 pixels in the xs direction along the scanning line SL and 240 pixels in the ys direction substantially perpendicular to the scanning line SL. 2 to 4, the optical curved surface 42 is not shown.

  Here, the laser beam corresponding to each projection direction PD is emitted from the curved surface array member 40 while expanding the divergence angle by reflection on the optical curved surface 42. Specifically, the spot diameter of each laser beam is enlarged by the optical curved surface 42 formed as a convex surface. The laser beam emitted from the curved array member 40 enters the light guide 50 as display light for displaying an image as a virtual image.

  As shown in FIGS. 2 and 3, the light guide 50 guides the display light from the curved surface array member 40 to the windshield 3. Specifically, the light guide unit 50 includes a magnifying mirror 52. The magnifying mirror 52 is formed by evaporating aluminum as a reflecting surface 52a on the surface of a base material made of synthetic resin or glass. The reflecting surface 52a is a concave surface that is curved in a concave shape because the center is concave. The magnifying mirror 52 has a function of enlarging the virtual image VI with respect to the size of the image in the projection area PA by reflecting the display light from the curved array member 40 toward the windshield 3.

  A light-transmitting dustproof cover 62 shown in FIG. 1 is disposed in a window portion provided above the vehicle of the housing 60. The display light reflected by the magnifying mirror 52 passes through the dustproof cover 62 from below the vehicle and enters the reflecting portion 3a of the windshield 3 above the vehicle. As described above, the display light reflected by the reflecting portion 3a reaches the eyelips ELP.

  In the optical system constituted by the HUD device 100 described above, as shown in FIG. 2, the conjugate point CP that is optically conjugate with the deflection point TP is a virtual reference plane of the incident adjustment unit 30 and the curved surface array member 40. This may occur depending on the configuration of the BS, the light guide 50, the reflection part 3a of the windshield 3, and the like.

  As a result of the use of the action of the negative lens 32, the conjugate point CP is located farther than the farthest portion Emd of the iris ELP with respect to the reflecting portion 3a. In the present embodiment, the farthest portion Emd is defined as a portion of the ellipsoidal eyelips ELP that is farthest from the reflecting portion 3a. For example, in a general passenger car, the farthest portion Emd is located on the headrest 4 side of the driver's seat in the eyelips ELP. More specifically, the conjugate point CP of the present embodiment is positioned so as to substantially overlap with the contour of the iris ELP at the farthest portion Emd.

  Here, as shown in FIG. 6, the laser beam is diffracted by the optical curved surface 42 being arranged in a lattice pattern on the curved surface arranging member 40. Along with the diffraction at the curved surface array member 40, a plurality of conjugate points are generated corresponding to the diffracted light of each order. In the present embodiment, the conjugate point CP located beyond the farthest portion Emd described above indicates a conjugate point having the highest intensity among a plurality of conjugate points. That is, the conjugate point of the order having a small intensity can be ignored because the influence on the visibility is relatively small, and all the conjugate points of the order need not be located beyond the farthest portion Emd. However, it is more preferable that the conjugate point of the order having the greatest intensity ± 1 is located beyond the farthest portion Emd, and the conjugate point of the order having the greatest intensity ± 2 is further from the farthest portion Emd. More preferably, it is located in In this embodiment, the conjugate point corresponding to the 0th-order diffracted light is the conjugate point of the highest order. In addition, in FIG. 6, the diffracted light of order m = -1, 0, 1 is typically shown.

(Function and effect)
The operational effects of the first embodiment described above will be described below.

  According to the first embodiment, the conjugate point CP that is optically conjugate with the deflection point TP is located farthest from the farthest portion Emd with respect to the reflecting portion 3a. Therefore, even if the laser beam emitted as display light is diffracted by the curved surface array member 40 in which a plurality of optical curved surfaces 42 are arranged in a lattice shape, as long as the occupant's eyes are present in the eyelips ELP, the occupant The deflection point TP is difficult to be imaged on the occupant's eye regardless of the eye's eye adjustment. In this way, it becomes difficult to recognize the occurrence of diffraction by the occupant whose eyes are located in the eyelips ELP, and therefore, uneven brightness in the virtual image VI is suppressed. Therefore, the HUD device 100 with high visibility of the virtual image VI can be provided.

  Moreover, according to 1st Embodiment, the incident adjustment part 30 has the negative lens 32 as a negative optical element whose optical power is negative. When such a negative lens 32 is arranged, an action of moving the conjugate point CP further away from the reflecting portion 3a occurs, and therefore the HUD in which the conjugate point CP is located farthest from the farthest portion Emd with respect to the reflecting portion 3a. The apparatus 100 can be easily realized.

  Further, according to the first embodiment, the conjugate point CP is positioned so as to overlap with the contour of the iris ELP at the farthest portion Emd. When positioned so as to overlap with the contour, the conjugate point CP does not unnecessarily move away from the eye position, so that it is possible to suppress luminance unevenness in the virtual image VI while suppressing a decrease in display light utilization efficiency.

  Further, in the eyelips ELP of the 90th percentile or more and 99th percentile or less, the probability that the deflection point TP is imaged before the occupant's eyes can be reduced to 10% or less or 1% or less, so that uneven brightness in the virtual image VI is suppressed.

  In the 90th percentile ELP ELP, the probability that the deflection point TP is imaged before the occupant's eyes can be reduced to 10% or less, so that the luminance unevenness in the virtual image VI is suppressed.

  Further, in the 99th percentile iris ELP, the probability that the deflection point TP is imaged before the occupant's eyes can be reduced to 1% or less, so that uneven brightness in the virtual image VI is suppressed.

(Second Embodiment)
As shown in FIGS. 7-9, 2nd Embodiment of this invention is a modification of 1st Embodiment. The second embodiment will be described with a focus on differences from the first embodiment.

  In the HUD device 200 of the second embodiment, as shown in FIGS. 7 and 8, the incident adjustment unit 230 is disposed on the optical path between the scanning unit 20 and the curved surface array member 240 as in the first embodiment. Yes. Here, unlike the first embodiment, the incident adjustment unit 230 does not have the negative lens 32 but has only the projection mirror 34. The projection mirror 34 has the same configuration as in the first embodiment.

  The curved surface arrangement member 240 of the second embodiment is a transmission type screen formed in a lens array shape having translucency by using synthetic resin or glass. Specifically, as shown in FIG. 9, the curved surface arranging member 240 has a plurality of optical curved surfaces 242 arranged in a lattice pattern as the incident-side refractive surface 240 a on the side facing the projection mirror 34 of the incident adjustment unit 230. . Each optical curved surface 242 is a smooth concave surface that is curved into a concave shape having a sufficiently larger curvature than the reflecting surface 34 a of the incident adjustment unit 30.

  In the present embodiment, the virtual reference surface BS, which is a virtual surface obtained by smoothly connecting the surface vertices 242a of the optical curved surfaces 242, has a concave shape that is concavely curved on the side opposite to the projection mirror 34. It has become. In other words, each optical curved surface 242 is arranged along a concave virtual reference surface BS. In particular, in this embodiment, the curvature and the sag amount in each optical curved surface 242 substantially match each other, and the virtual reference surface BS forms a spherical circumscribed surface with respect to each optical curved surface 242.

  On the other hand, on the side facing the magnifying mirror 52 of the light guide unit 50, the exit-side refractive surface 240b of the curved surface array member 240 is a smooth single convex surface that curves in a convex shape. The exit-side refractive surface 240b is set to have a sufficiently smaller curvature than each optical curved surface 242.

  Further, the curvature of the exit-side refracting surface 240b is set smaller than the curvature of the virtual reference surface BS. Here, the optical power of the curved surface array member 240 calculated by replacing the curvature of the optical curved surface 242 with the curvature of the virtual reference surface BS on the incident-side refractive surface 240a is defined as the reference optical power. Then, the reference optical power is negative. Due to such a shape, the curved surface array member 240 has a macroscopic negative meniscus lens shape.

  Note that a virtual surface obtained by smoothly connecting the boundaries 242b of the optical curved surfaces 242 may be defined as a virtual reference surface. Even under such a definition, the reference optical power is negative.

  As shown in FIG. 7, the laser beam corresponding to each projection direction PD is emitted from the curved surface array member 240 while expanding the divergence angle due to refraction at the optical curved surface 242. The spot diameter of each laser beam is enlarged by the optical curved surface 242 formed as a concave surface. On the other hand, the spot center of each laser beam is deflected on the average in accordance with the negative reference optical power. Therefore, the curved surface array member 240 acts to keep the conjugate point CP away from the deflection point TP in the optical system configured by the HUD device 100.

  As a result of the use of the action of the curved surface array member 240, the conjugate point CP is located beyond the farthest part Emd of the iris ELP with respect to the reflecting part 3a. Therefore, also in the second embodiment, it is possible to achieve an effect according to the first embodiment.

  According to the second embodiment, the reference optical power is negative. Such a curved surface array member 240 has an effect of moving the conjugate point CP further with respect to the reflecting portion 3a while expanding the spread angle based on the curvature of each optical curved surface 242. Therefore, the HUD device 200 in which the conjugate point CP is located farthest from the farthest portion Emd with respect to the reflecting portion 3a can be easily realized.

(Third embodiment)
As shown in FIG. 10, the third embodiment of the present invention is a modification of the first embodiment. The third embodiment will be described with a focus on differences from the first embodiment.

  In the HUD device 300 of the third embodiment, the incident adjustment unit 330 is arranged on the optical path between the scanning unit 20 and the curved surface array member 40, as in the first embodiment. Here, unlike the second embodiment, the incident adjustment unit 330 does not have the negative lens 32 but has only the projection mirror 334. The reflection surface 334a of the projection mirror 334 is a smooth free-form surface that is concavely curved due to the depression at the center, but the curvature of the reflection surface 334a is set to be smaller overall than in the first embodiment, The optical power of the projection mirror 334 is small. The curved surface array member 40 has the same configuration as that of the first embodiment.

  Since the curvature of the projection mirror 334 is smaller than that in the first embodiment, the conjugate point CP is located farthest from the farthest portion Emd of the iris ELP with respect to the reflecting portion 3a also in the third embodiment. . More specifically, the conjugate point CP of the third embodiment is located farther than the farthest portion Emd with respect to the reflecting portion 3a.

  According to the third embodiment described above, the conjugate point CP located farther than the farthest portion Emd with respect to the reflecting portion 3a can surely prevent the deflection point TP from being imaged on the occupant's eye, so a virtual image. Luminance unevenness in VI is suppressed.

(Other embodiments)
Although a plurality of embodiments of the present invention have been described above, the present invention is not construed as being limited to these embodiments, and various embodiments and combinations can be made without departing from the scope of the present invention. Can be applied.

  With respect to the second embodiment, various shapes can be adopted as the curved surface array member that is a transmission type screen formed in a lens array shape. In Modification 1 as such various shapes, as shown in FIG. 11, the curved surface array member 240 arranges a plurality of optical curved surfaces 242 in a grid pattern as the exit side refractive surface 240b instead of the incident side refractive surface 240a. May be. Further, the curved surface arranging member 240 may arrange a plurality of optical curved surfaces 242 in a lattice pattern on both the incident side refractive surface 240a and the exit side refractive surface 240b.

  In Modification 2 as such various shapes, as shown in FIG. 12, the exit-side refractive surface 240b of the curved surface array member 240 may be a single concave surface that is curved in a concave shape, and is shown in FIG. As such, it may be a flat surface.

  In the third modification as such various shapes, as shown in FIGS. 14 and 15, the curved surface arrangement member 240 is a first member 244 that faces the projection mirror 34 of the incident adjustment unit 230, and the magnifying mirror 52 of the light guide unit 50. And a second member 246 facing each other. The exit-side refracting surface 244b of the first member 244 and the incident-side refracting surface 246a of the second member 246 each have a plurality of optical curved surfaces 242 arranged in a lattice pattern. Specifically, on the exit-side refractive surface 244b of the first member 244, each optical curved surface 242 is a smooth convex surface that curves in a convex shape, and a virtual reference surface BS (not shown) is convex toward the second member 246 side. It is a convex surface that curves. In the incident side refractive surface 246a of the second member 246, each optical curved surface 242 is a smooth concave surface curved in a concave shape, and a virtual reference surface BS (not shown) is a concave surface curved in a concave shape on the opposite side to the first member 244. It has become. The exit-side refracting surface 244b of the first member 244 and the incident-side refracting surface 246a of the second member 246 are arranged in a state of being bonded together or in close proximity to each other.

  In particular, in the configuration of FIG. 14, the incident side refractive surface 244a of the first member 244 is a flat surface, and the exit side refractive surface 246b of the second member 246 is also a flat surface. Since the refractive index of the second member 246 is higher than the refractive index of the first member 244, the reference optical power of the curved surface array member 240 is negative.

  In particular, in the configuration of FIG. 15, the incident-side refractive surface 244a of the first member 244 is a smooth concave surface that curves in a concave shape. The exit side refracting surface 246b of the second member 246 is also a smooth concave surface curved in a concave shape. Further, there is a difference in refractive index between the first member 244 and the second member 246. The reference optical power of the curved array member 240 is negative.

  As a fourth modification related to the first embodiment, as shown in FIG. 16, in the curved surface array member 40, each optical curved surface 42 is a smooth convex surface curved in a convex shape, and the virtual reference surface BS is used as the incident adjustment unit 30 and It may be a convex surface that is convex toward the light guide 50 side and curved.

  As a fifth modification related to the first embodiment, as shown in FIG. 17, in the curved-surface array member 40, each optical curved surface 42 may be a smooth concave surface curved in a concave shape. Specifically, in each optical curved surface 42 formed as a concave surface, the spot diameter of each laser beam can be once narrowed immediately after emission from the curved array member 40, but then it is expanded again.

  As a sixth modification, at least one of the curvature and the sag amount may be different between the optical curved surfaces 42 and 242 arranged in a lattice shape. As an example of this, the sag amounts of the adjacent optical curved surfaces 42 and 242 may be set to be alternately different. In such a configuration, if the surface vertices 42a and 242a are to be connected smoothly, unevenness may occur and the curvature of the virtual reference surface BS may not be determined. In this case, instead of the surface vertices 42a and 242a, a virtual surface obtained by smoothly connecting the boundaries of the optical curved surfaces 42 and 242 may be used as the virtual reference surface BS. In addition, a virtual surface obtained by fitting the coordinates of the surface vertices 42a and 242a to a spherical surface or the like may be used as the virtual reference surface BS.

  As a modified example 7, the light guide unit 50 may be added with optical elements such as a mirror and a lens, and the magnifying mirror 52 may be replaced with another optical element. Further, the light guide 50 itself may not be provided.

  100, 200, 300 HUD device, 1 vehicle, 3 windshield (projection member), 3a reflection unit, 10 laser light source unit, 20 scanning unit, 30, 230, 330 incidence adjustment unit, 32 negative lens (negative optical element) , 40, 240 Curved surface array member, 42a, 242a Surface vertex, 242b boundary, ELP iris, VI virtual image, TP deflection point, Emd farthest part, CP conjugate point, BS Virtual reference plane

Claims (8)

It is mounted on a vehicle (1) that can define an iris (ELP), projects display light toward the reflecting portion (3a) of the projection member (3), and reflects the display light at the reflecting portion. A head-up display device that displays a virtual image (VI) that is visible from within the eyelips by reaching the inside,
A laser light source section (10) for emitting a laser beam;
A scanning unit (20) for scanning the laser beam by deflecting the laser beam at a deflection point (TP);
A plurality of optical curved surfaces (42, 242) are arranged in a lattice pattern, and an image is drawn by the incidence of the laser beam scanned by the scanning unit, and the divergence angle of the laser beam is set by each of the optical curved surfaces. A curved surface array member (40, 240) that emits the display light while being enlarged,
When the farthest part (Emd) which is the farthest from the reflection part among the irises is defined,
A conjugate point (CP) optically conjugate with the deflection point is a head-up display device positioned farther than the farthest portion with respect to the reflecting portion. An incident adjustment unit (30) that is disposed on an optical path between the scanning unit and the curved surface array member and adjusts an incident state of the laser beam scanned by the scanning unit on the curved surface array member;
The head-up display device according to claim 1, wherein the incident adjustment unit includes an optical element having a negative optical power. A virtual surface obtained by smoothly connecting surface vertices (242a) of the optical curved surfaces or boundaries (242b) between the optical curved surfaces is defined as a virtual reference surface (BS),
When the optical power of the curved array member calculated by replacing the curvature of each optical curved surface with the curvature of the virtual reference surface is defined as a reference optical power,
The head-up display device according to claim 1, wherein the reference optical power is negative.   The head-up display device according to claim 1, wherein the conjugate point is positioned so as to overlap an outline of the iris at the farthest portion.   4. The head-up display device according to claim 1, wherein the conjugate point is located farther than the farthest portion with respect to the reflection portion. 5.   6. The head-up display device according to claim 1, wherein the eyelips is an eyelips of 90th to 99th percentile.   The head-up display device according to claim 1, wherein the eyelips are 90th percentile eyelips.   The head-up display device according to claim 1, wherein the eyelips are 99th percentile eyelips.

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