JP5333782B2 - Head-up display device - Google Patents

Description

  The present invention relates to a head-up display device that visually provides various types of information such as instrument information to a driver of an automobile or the like using a projection image by a projector device.

  2. Description of the Related Art Conventionally, a head-up display device that projects various information images such as instrument information formed by a liquid crystal display and map information in a navigation device on a front window in a moving body such as an automobile and transmits the information to a driver is known. It has been. Patent Documents 1 to 3 disclose the use of such a head-up display device in a vehicle.

  Patent Document 1 includes a dimming screen disposed behind a transmissive dot matrix liquid crystal display panel capable of graphic display, and a backlight light source disposed behind the dimming screen. A head-up display device is disclosed that includes a display that reflects information display on a translucent reflector provided in front of the windshield. According to this head-up display device, the washout phenomenon of the display device in the head-up device for a vehicle that projects and displays the display image of the display device on a translucent reflector (combiner) disposed in the front view of the driver's seat. In addition, the durability of the backlight used to transmit and illuminate the display can be improved.

  Further, in Patent Document 2, a light emitting display source including a radiation mechanism that radiates display images such as various traveling data is arranged on the interior side of the roof panel located above the driver's seat, and a predetermined part of the instrument panel is arranged. Further, there is disclosed a vehicle head-up display provided with a mirror for projecting a display image radiated from a light emitting display source onto a front wind panel in front of a driver's seat. According to this vehicle head-up display, a large installation space is not required inside the vehicle instrument panel, and the layout becomes easy.

  Further, Patent Document 3 discloses that a transparent hologram that reproduces diffused light by reflection diffraction is used as a combiner in a head-up display device. By using a combiner using such a hologram, it is possible to provide a combiner and a head-up display device that can observe a bright reproduced image with less blur without requiring very high flatness. It becomes possible.

  Here, an embodiment of the head-up display device will be briefly introduced with reference to FIGS. 9 and 10. FIG. 9 shows an embodiment in which various configurations of a head-up display device are incorporated in an instrument panel. Video information such as vehicle instrument information and map information from the navigation device is output and displayed on the liquid crystal display panel. A backlight as a light source is installed on the back surface of the liquid crystal display panel. By irradiating the liquid crystal display panel from the back surface, an image formed on the liquid crystal display panel is irradiated onto a concave mirror as an optical system enlarging element. The image reflected and enlarged by the concave mirror is projected on the inside of the front window or a transmissive reflector provided on the front window.

  The operator can view the display image (virtual image) located in front of the front window at the same time as the scenery outside the vehicle. In addition, by setting the distance to the display image (distance L) as far as possible, the operator can check video information such as instrument information and map information with a small amount of movement of the focal position.

  FIG. 10 is a view showing the state from behind the vehicle driver's seat, in which various types of video information are displayed within a display range surrounded by a broken line in the front window, and the driver is provided with various types of information arranged in the instrument panel. It is possible to obtain various information by video while paying attention to driving the vehicle without dropping the line of sight to the instruments.

JP 2000-131642 A Japanese Utility Model Publication No. 6-29095 Japanese Patent Laid-Open No. 9-179058

  With the recent advancement of information terminal equipment and the development of communication infrastructure, the amount of information that can be supplied to the driver of the vehicle has increased dramatically. Also in the head-up display device described above, it is desirable to increase the display range in order to visually transmit a large amount of information. In particular, in a head-up display device that needs to visually recognize information displayed while maneuvering a vehicle, information to be displayed such as characters, icons, various parts such as a speedometer is given a certain size. This is preferable in terms of visibility.

  In a head-up display device, it is difficult to increase the display range with one projector device from the viewpoint of the irradiation angle of the projector device, and therefore it is possible to secure a wide display range using a plurality of projector devices. Be considered.

  FIG. 1 is an image diagram when a wide range display is performed by dividing the display range in this way. Thus, according to the wide display range formed in the display range 1 and the display range 2, it is possible to increase the amount of information provided to the observer sitting in the driver's seat, and to display characters, Various information such as icons can be displayed in a large size, and information that is easy for the observer to view can be provided.

  FIG. 2 is a schematic diagram when such a wide-range display is assumed in a conventional head-up display device. Here, it is assumed that incident light 1 and incident light 2 output from two projector apparatuses are reflected by concave mirrors 15R and 15L, respectively, and then diffracted light 1 and diffracted light 2 are formed for an observer. doing. Each incident light is reflected and magnified by the concave mirrors 15R and 15L, and is surface-reflected inside the front window 21.

  There are few mounting problems with respect to the front of the observer, that is, the concave mirror 15R and the projector device that makes the incident light 1 incident thereon. However, since the surface reflection is a reflection in which the incident angle and the reflection angle are equal to each other, in an environment where the driver as an observer is seated biased to the left or right of the front window 21, the incident light 2 and the diffraction on the concave mirror 15L are diffracted. It is necessary to set the angle α formed by the light 2 shallow, and it is difficult to mount the concave mirror 15L and the projector device that makes the incident light 2 incident on the concave mirror 15L.

In order to solve the above-described problems, a head-up display device according to the present invention includes a transparent base material disposed opposite to an observation position, and a first holographic element disposed in front of the observation position of the transparent base material. An optical element, a second holographic optical element disposed on the side of the observation position of the transparent substrate , a first projector unit that projects a first image on the first holographic optical element, A second projector unit that projects a second image onto a second holographic optical element, wherein the first holographic optical element and the second holographic optical element include the first image , an angle selectivity of Ru to diffract the second image in the direction of the observation position, is characterized by forming a virtual image to image distant to the observation position.

In the head-up display device of the present invention, the first image and the second image are joined to form one image.
Further, in the head-up display device of the present invention. The first holographic optical element, said second holographic optical element is disposed on the transparent substrate with a partially overlapped with each other It is characterized by that.

  Furthermore, in the head-up display device of the present invention, at least one of the first holographic optical element and the second holographic optical element has an optical magnification function.

  According to the head-up display device of the present invention, the first holographic optical element and the second holographic optical element are disposed on the transparent substrate disposed to face the observation position, and the first projector is provided. By diffracting the image projected by the apparatus and the second projector apparatus in the direction of the observation position, it becomes possible to provide a wide range of information to the observer.

The image figure in the case of performing wide display by dividing a display range. The figure for demonstrating the problem in the case of employ | adopting the conventional format. The figure which shows the head-up display apparatus which concerns on embodiment of this invention. 1 is a diagram showing a projector device according to an embodiment of the present invention. The figure for demonstrating the lens function by a holographic optical element. The figure which shows the optical path of the head-up display apparatus which concerns on embodiment of this invention. The figure which shows the mode of mounting of a head-up display apparatus. The figure which shows the bonding structure of the holographic optical system which concerns on other embodiment. The figure which shows the conventional head-up display apparatus. The figure which shows the mode of the image display in the vehicle interior by a head-up display apparatus.

  FIG. 3 is a view showing a part of the head-up display device according to the embodiment of the present invention, and shows a case where it is adopted in an automobile. Note that the head-up display device of the present invention is not limited to an automobile, and can be employed in a display device for a driver of various vehicles, a game machine, or a simulation device.

  A front window 21 of the automobile is arranged in the observation direction of the observer, and a holographic optical system 20 is stuck inside. The holographic optical system 20 is an optical member having a see-through (transparency) property that does not impair external light and having a diffraction function, and is created by recording an interference pattern of object light and reference light. In this embodiment, it functions as a combiner that superimposes the scenery outside the passenger compartment and the video information of the projector device 10 at the observation position.

The projector device 10 (“projector unit” in the present invention) is a device that projects an image based on various types of input video information, and can use various methods such as a liquid crystal projector, a DLP projector, and an LCOS projector. It is. The image projected from the projector device 10 is diffracted by the holographic optical system 20 and is observed as a virtual image that forms an image far away at the observer's observation position. The observer, that is, the pilot, can visually recognize the scenery outside the passenger compartment and the video information from the projector device 10 without changing the line of sight. In the present embodiment, the imaging distance can be changed by changing the focal length of the projector device 10. As a result, the imaging distance is shortened when the vehicle ahead is near, and the imaging distance is increased when there is no vehicle ahead or far away. Make it visible.

  FIG. 4 is a diagram showing a projector apparatus according to the embodiment of the present invention. In the present embodiment, a laser is used as a light source, and a liquid crystal display element is used in an image forming unit that forms an image. The laser light source 11 is a light source device including a laser semiconductor 112, a diverging optical system 111, and the like, and the output light radiated from the laser semiconductor 112 is aligned in a predetermined irradiation cross-sectional shape by the diverging optical system 111. Output to the outside.

  The output light output from the laser light source 11 is adjusted to a necessary area as a backlight by the beam expander 12 and then irradiated to the back of the image forming unit 13. In the present embodiment, a liquid crystal display unit using a liquid crystal display element 131 is employed as the image forming unit 13. The output light of the laser light source 11 is adjusted by the diffusion plate 132 so that the intensity distribution is uniform, and then the image formed on the liquid crystal display element 131 is irradiated from behind and projected through the projection optical system 14. Form an image.

  An observer observes this projection image through the holographic optical system 20. This is made possible by the polarization function of the holographic optical system 20, but by providing the holographic optical system 20 with a lens function (optical magnification function), it is possible to provide a large image to the observer. In addition, the projection optical system 14 in the projector apparatus 10 can be downsized, and the projector apparatus 10 itself can be downsized.

  FIG. 5 is a diagram for explaining the holographic optical system. Since the holographic optical system 20 has high see-through properties, extraneous light passes through the holographic optical system 20 with almost no loss. On the other hand, incident light (reproduced light) emitted from the projector device 10 is diffracted in a predetermined direction by the holographic optical system 20 (angle selectivity). By manufacturing the holographic optical system 20 so that the diffracted light is diffracted toward the condensing point, a lens function (optical magnification function) can be provided.

  FIG. 6 is a diagram illustrating an optical path when the head-up display device according to the embodiment of the present invention is viewed from above. In the present embodiment, by using a plurality of head-up display devices described with reference to FIG. 3, it is possible to provide an observer with a wide visible range.

  In the present embodiment, an optical system 20 having a first holographic optical element 20a and a second holographic optical element 20b is attached to the inner surface of a front window 21 formed of a transparent substrate. In addition, about the arrangement | positioning method of the holographic optical system 20 with respect to the windshield 21, in addition to sticking to an inner surface in this way, it sticks to the outer surface of the front window 21, or pinches | interposes between two transparent base materials etc. An appropriate method can be adopted. Further, the holographic optical system 20 may be disposed on a transparent base material provided separately from the front window 21 as well as the front window 21.

The first holographic optical element 20a and the second holographic optical element 20b are disposed adjacent to each other with a line segment AA ′ as a boundary. The incident light 1 emitted from the first projector device 10a is diffracted as diffracted light 1 in the direction of the observer's observation position by the first holographic optical element 20a, and forms an observation image at the observation position. On the other hand, the incident light 2 emitted from the second projector device 10b is diffracted as diffracted light 2 in the direction of the observer's observation position by the second holographic optical element 20b, and an observation image is formed at the observation position. Form.

  In particular, in the present embodiment, the second holographic optical element 20b diffracts the incident light 2 from the second projector device 10b at a steep angle for observation by the excellent angle selectivity of the holographic optical element. It is possible to guide in the direction of the person.

  The first holographic optical element 20a and the second holographic optical element 20b may be arranged at a distance from each other, but the image projected by the projector device 10a and the image projected by the projector device 10b are joined. When one image is made, it is possible to suppress a sense of incongruity at the joint portion by adjoining without any gap.

  FIG. 7 is a diagram showing a state of mounting the head-up display device according to the embodiment of the present invention. As described above, in the present embodiment, a wide display range including the display range 1 and the display range 2 can be formed, and it is possible to provide a lot of information to the observer and to provide the information to be provided. It becomes possible to ensure visibility.

  As described above, in the present embodiment, the first holographic optical element 20a and the second holographic optical element 20b are disposed on the front window 21 (transparent substrate) disposed to face the observation position, and the first By diffracting the images projected by the first projector device 10a and the second projector device 10b in the direction of the observation position, a head-up display device capable of providing a wide visible range to the observer is made possible. .

  In particular, the projector device 10b disposed on the side away from the observer should be arranged in a free layout without requiring consideration for securing an optical path due to the excellent angle selectivity of the holographic optical element. Is possible.

  In the present embodiment, the first and second projector apparatuses 10a and 10b and the first and second holographic optical elements 20a and 20b corresponding to the first and second projector apparatuses 10a and 10b have been described. The number is not limited to two as long as it is a relationship associated with each other, and may be three or more.

  In the case where, for example, when one image is created by joining images, the first holographic optical element 20a and the second holographic optical element 20b are adjacent to each other. Although it has been described that the second holographic optical element 20b is preferably disposed adjacently without a gap, it is very difficult to dispose the second holographic optical element 20b adjacently without a gap.

  FIG. 8 is a view showing a state in the vicinity of adjacent portions of the holographic optical elements 20a and 20b according to the embodiment of the present invention. FIG. 8 (a) shows a side sectional view, and FIG. Is a front view. In the present embodiment, in the adjacent portion, the first holographic optical element 20a and a part of the second holographic optical element 20b are bonded to each other, thereby solving the problem in the adjacent state. Yes.

  The side sectional view of FIG. 8A shows that the first holographic optical element 20a and the second holographic optical element 20b are line segments AA inside the front window 21 (vehicle compartment side). A state in which the adjacent portions indicated by 'are pasted to each other is shown.

The front view of FIG. 8B shows a state where the two holographic optical elements 20a and 20b are bonded to each other in the height direction (Y-axis direction). In the present embodiment, the holographic optical element 20a positioned on the right side is bonded to the holographic optical element 20b positioned on the left side.

  The two holographic optical elements 20a and 20b are bonded to each other so that an overlapping region is formed. Since each holographic optical element 20a, 20b is originally provided with optical characteristics so as to function one by one, this overlap region is different from the original optical characteristics. However, as described with reference to FIG. 3, the head-up display device according to the present embodiment is configured to observe an image formed at a sufficiently far distance, so that even when two optical characteristics overlap, it is visually There is little sense of incongruity.

  Therefore, as in the present embodiment, the first holographic optical element 20a and the second holographic optical element 20b are superposed on each other in the adjacent portion, thereby joining the images from the projector devices 10a and 10b. Even in such a case, it is possible to suppress a sense of incongruity in the adjacent portion and provide a highly continuous video.

  Note that the present invention is not limited to these embodiments, and embodiments configured by appropriately combining the configurations of the respective embodiments also fall within the scope of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Projector apparatus, 10a ... 1st projector apparatus, 10b ... 2nd projector apparatus, 11 ... Laser light source, 111 ... Divergence optical system, 112 ... Laser semiconductor, 12 ... Beam expander, 13 ... Image formation part, 131 ... LCD, 132 ... Diffusion plate, 14 ... Projection optical system, 15R, 15L ... Concave mirror, 20 ... Holographic optical system, 20a ... First holographic optical element, 20b ... Second holographic optical element, 21 ... Front window

Claims (4)

A transparent substrate disposed opposite to the observation position;
A first holographic optical element disposed in front of the observation position of the transparent substrate;
A second holographic optical element disposed on the side of the observation position of the transparent substrate;
A first projector unit that projects a first image onto a first holographic optical element;
A second projector unit that projects a second image onto the second holographic optical element,
Said first holographic optical element and the second holographic optical element has a first image, the angle selectivity of Ru is diffracted in the direction of the observation position of the second image, the observation A head-up display device, wherein a virtual image is formed at a position far away . The first image and the second image are joined to form one image.
The head-up display device according to claim 1. Said first holographic optical element, said second holographic optical element, according to claim 1 or claim wherein a portion is disposed on the transparent substrate in a state of being mutually superimposed head-up display apparatus according to 2. The head-up according to any one of claims 1 to 3 , wherein at least one of the first holographic optical element and the second holographic optical element has an optical magnification function. Display device.

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