WO2017203916A1 - Head-up display device - Google Patents

Abstract

The present invention further reduces the size of a head-up display device. This head-up display device has: a video display device 30 that has a light source and a display element, and forms a video on the display element; and a virtual image optical system that displays a virtual image ahead of a vehicle by reflecting light emitted from the video display device 30 on a windshield or a combiner. The virtual image optical system includes a concave mirror 41 and a distortion correcting lens 43. The distortion correcting lens 43 is disposed between the video display device 30 and the concave mirror 41, and is configured such that the distortion of a virtual image corresponding to the viewpoint of a driver is corrected due to the shape of the concave mirror 41 and the shape of the distortion correcting lens 43. The concave mirror 41 and the distortion correcting lens 43 are positioned and held by an optical component holding member 53 formed from a prescribed material. The optical component holding member 53 is stored in a housing comprising an outer case 54 and an outer cover part 51.

Description

Head-up display device

The present invention relates to a technology for a head-up display device, and more particularly to a technology effective when applied to a head-up display device that projects an image on a transparent glass element or the like.

For example, in vehicles such as automobiles, information such as vehicle speed and engine speed is usually displayed on an instrument panel in the dashboard. In addition, a screen such as a car navigation is displayed on a display that is incorporated in the dashboard or installed on the dashboard. Since it is necessary for the driver to move his / her line of sight when visually recognizing such information, information such as vehicle speed and information related to car navigation is used as a technology to reduce the amount of movement of the line of sight. 2. Description of the Related Art A head-up display (Head-Up-Display, which may be referred to as “HUD” below) that projects and displays on a (wind shield) or the like is known.

As a technology related to HUD, for example, Japanese Patent Laying-Open No. 2015-194707 (Patent Document 1) includes a device that displays an image and a projection optical system that projects the image displayed on the display device. A display device that reduces screen distortion and realizes downsizing in the entire viewpoint area is described. Here, the projection optical system has a first mirror and a second mirror in the order of the optical path of the observer from the display device. The incident angle in the image major axis direction of the first mirror, the incident angle in the image minor axis direction of the first mirror, the interval between the image display surface of the display device and the first mirror, and the virtual image visually recognized by the observer It is described that the size of the HUD device can be reduced by configuring so that the relationship with the width in the horizontal direction satisfies a predetermined relationship.

JP 2015-194707 A

In the prior art described in Patent Document 1, it is said that the configuration of the apparatus can be reduced in size, but there is a restriction on the reduction in size. That is, in the technique described in Patent Document 1, it is necessary to arrange two mirrors between the observer and the display device. At this time, in order to prevent the reflected light beam from the first mirror from being blocked by the second mirror, the degree of freedom of mirror arrangement is limited. That is, there is a restriction in arranging the two mirrors close to each other, and it is necessary to arrange them apart from each other to some extent, and this amount hinders downsizing of the apparatus configuration.

Therefore, an object of the present invention is to provide a head-up display device that realizes further downsizing of the device.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

Of the inventions disclosed in this application, the outline of typical ones will be briefly described as follows.

A head-up display device according to a representative embodiment of the present invention is a head-up display device that displays a virtual image according to the video to a driver by projecting the video on a windshield of a vehicle. And a display device that forms the image on the display device, and a virtual image that displays the virtual image in front of the vehicle by reflecting light emitted from the video display device with the windshield And an optical system.

The virtual image optical system includes a concave mirror and an optical element, and the optical element is disposed between the video display device and the concave mirror, and includes a shape of the concave mirror and a shape of the optical element. The concave mirror and the optical element are each positioned and held by a holding member made of a predetermined material, so as to correct distortion of the virtual image obtained corresponding to the viewpoint position of the driver. The holding member is housed in the housing.

Among the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows.

That is, according to the representative embodiment of the present invention, it is possible to further reduce the size of the head-up display device.

It is the figure which showed the outline | summary about the example of the operation | movement concept of the head-up display apparatus which is Embodiment 1 of this invention. (A), (b) is the figure which showed the outline | summary about the example of the mounting form of the head-up display apparatus which is Embodiment 1 of this invention. It is the figure which showed the outline | summary about the example of the mounting form of the video display apparatus in Embodiment 1 of this invention. It is the figure which showed the outline | summary about the example of the mounting form of the light guide in Embodiment 1 of this invention. It is the functional block diagram which showed the outline | summary about the structural example of the whole head-up display apparatus which is Embodiment 1 of this invention. It is the figure which showed the outline | summary about the example of the hardware constitutions which concern on acquisition of the vehicle information in Embodiment 1 of this invention. It is the functional block diagram which showed the detail about the structural example in Embodiment 1 of this invention. (A)-(c) is the figure which showed the outline | summary about the structural example of the optical system which displays the virtual image in Embodiment 1 of this invention, and size reduction of an apparatus. It is the figure which showed the outline | summary about the example of correction | amendment of the distortion and aberration by the distortion correction lens in Embodiment 1 of this invention. It is the flowchart which showed the outline | summary about the example of the initial stage operation in Embodiment 1 of this invention. It is the flowchart which showed the outline | summary about the example of the normal operation | movement in Embodiment 1 of this invention. It is the flowchart which showed the outline | summary about the example of the brightness level adjustment process in Embodiment 1 of this invention. It is the figure which showed the outline | summary about the example of the mounting form of the head-up display apparatus which is Embodiment 2 of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof will be omitted. On the other hand, parts described with reference numerals in some drawings may be referred to with the same reference numerals although not illustrated again in the description of other drawings. In each embodiment described below, a case where a head-up display (HUD) device is installed in a vehicle such as an automobile will be described as an example, but the present invention can also be applied to other vehicles such as trains and airplanes. Moreover, it is applicable also to the HUD apparatus used for uses other than a vehicle.

(Embodiment 1)
<Overview>
FIG. 1 is a diagram showing an outline of an example of an operation concept of the head-up display device according to the first embodiment of the present invention. In the HUD device 1 of the present embodiment, an image displayed by the image display device 30 arranged in the housing 50 (or a place that can be attached to and detached from the housing 50 as will be described later) is displayed by the concave mirror 41. Reflected and projected onto the windshield 3 of the vehicle 2.

Here, the member to be projected is not limited to the windshield 3 and may be another member such as a combiner as long as the image is projected. The video display device 30 is configured by, for example, a projector having a backlight, an LCD (Liquid Crystal Display), or the like. A self-luminous VFD (Vacuum Fluorescent Display) or the like may be used. An image may be displayed on a screen by a projection device. As such a screen, for example, a microlens array in which microlenses are two-dimensionally arranged may be used.

The concave mirror 41 is constituted by, for example, a free-form surface mirror or a mirror having an optical axis asymmetric shape. More specifically, the shape of the concave mirror 41 is set so that, for example, the upper region (that is, the light beam reflected here is reflected below the windshield 3) in order to reduce the distortion of the virtual image. In the case where the distance from the viewpoint of the driver 5 is shortened), the radius of curvature is relatively decreased so that the enlargement ratio is increased. On the other hand, in the area below the concave mirror 41 (that is, the light beam reflected here is reflected above the windshield 3, the distance from the viewpoint of the driver 5 is relatively long), the enlargement ratio is small. The radius of curvature is relatively increased. By disposing the video display device 30 so as to be inclined with respect to the optical axis of the concave mirror 41, the difference in image magnification as described above may be corrected to reduce the generated distortion itself.

The driver 5 views the image projected as a virtual image in front of the transparent windshield 3 by viewing the image projected on the windshield 3. By adjusting the angle of the concave mirror 41 and adjusting the position at which the image is projected onto the windshield 3, the display position of the virtual image viewed by the driver 5 may be adjusted in the vertical direction. In addition, the content displayed as a virtual image is not specifically limited, For example, vehicle information, navigation information, the image | video of the front scenery image | photographed with the camera image (a monitoring camera, an around viewer, etc.) which is not illustrated can be displayed suitably.

In order to increase the size of the virtual image visually recognized by the driver 5 to a practical level, it is necessary to increase the distance from the concave mirror 41 to the virtual image. As a result, the size of the HUD device 1 must be increased. There wasn't. In addition, since the windshield 3 on which the image is projected is normally tilted forward and backward as viewed from the driver 5, it is difficult to match the image magnification between the upper and lower portions of the virtual image.

On the other hand, in the related art as described in Patent Document 1 described above, in addition to the concave mirror 41, an optical path folding mirror is provided between the driver 5 and the display device (the video display device 30 in the present embodiment). The optical path difference in the region where the image magnification is partially different is reduced. Accordingly, it is possible to reduce a partial change in image magnification (image distortion) and to reduce the volume of the apparatus while securing a distance from the concave mirror 41 to the virtual image.

On the other hand, since the two mirrors of the concave mirror 41 and the optical path folding mirror are required, the degree of freedom of the mirror arrangement is limited, and the two mirrors need to be arranged apart from each other. This is an obstacle to downsizing. In addition, regarding the correction of the aberration generated in the virtual image visually recognized by the driver 5, neither the necessity nor specific means are described or considered in Patent Document 1.

On the other hand, in the HUD device 1 of the present embodiment, in order to realize further downsizing of the device, the mirror for forming a virtual image is configured by only one concave mirror 41 as shown in FIG. . Further, between the driver 5 and the video display device 30, for example, a distortion correction lens 43 having at least one concave surface (having negative refractive power) is disposed as a transmissive optical element. Thereby, it is possible to improve the visibility by reducing the distortion and aberration of the virtual image visually recognized by the driver 5 to a level having no practical problem while suppressing the increase in size and complexity of the HUD device 1. That is, by controlling the emission direction of the light beam to the concave mirror 41 by the distortion correction lens 43, the distortion aberration is corrected in accordance with the shape of the concave mirror 41.

In order to further improve the aberration correction capability, a plurality of distortion correction lenses 43 may be provided. Alternatively, a distortion mirror may be reduced by disposing a curved mirror instead of the distortion correction lens 43 and controlling the incident position of the light beam on the concave mirror 41 simultaneously with the folding of the optical path. Thus, even if an optical element optimally designed to further improve the aberration correction capability is provided between the concave mirror 41 and the image display device 30, it does not depart from the technical idea or scope of the present invention. Needless to say.

Further, by changing the thickness in the optical axis direction of the optical element including the distortion correction lens 43 and the like, in addition to the original aberration correction, the optical distance between the concave mirror 41 and the image display device 30 is changed, thereby changing the virtual image. It is also possible to adopt a configuration in which the display position is continuously changed from far to near.

On the other hand, as a factor that degrades the image quality of the HUD device 1, the image light emitted from the image display device 30 toward the concave mirror 41 is reflected by the surface of the distortion correction lens 43 disposed in the middle, and the image display device 30. It is known that the light is reflected again and superimposed on the original image light. For this reason, in this embodiment, for example, an antireflection film is formed on the surface of the distortion correction lens 43 to suppress reflection. Furthermore, the shape of the distortion correction lens surface of at least one of the image light incident surface and the light exit surface of the distortion correction lens 43 is designed so that the reflected light returning to the image display device 30 is not extremely concentrated on a part thereof. It is preferable to do. Further, in the video display device 30, the deterioration of image quality can be reduced by arranging a polarizing plate for absorbing the reflected light from the distortion correction lens 43 as described above.

<Mounting form of HUD device>
FIG. 2 is a diagram showing an outline of an example of a mounting form of the head-up display device according to the embodiment of the present invention. FIG. 2A is a perspective view showing an example of an external appearance centering on the housing 50 of the HUD device 1. FIG. 2B is a perspective view showing a state in which the HUD device 1 shown in FIG.

As shown in FIG. 2B, the HUD device 1 has a configuration in which an optical component holding member 53 is housed in an exterior case 54 and the upper portion is covered with an exterior lid portion 51. Each member of the exterior case 54 and the exterior lid portion 51 constitutes the housing 50 in the HUD device 1 shown in FIG. The video display device 30 is attached to the opening of the outer case 54.

The exterior lid 51 has an opening for emitting image light toward the windshield 3, and the opening is covered with an antiglare plate 52 (glare trap).

The optical component holding member 53 is a member that holds the concave mirror 41 and the distortion correction lens 43 in the HUD device 1 shown in FIG. Although details will be described later, in the present embodiment, since the member holds the optical component, the member is formed of a material having characteristics of high heat resistance, high rigidity, and high dimensional accuracy.

Even if other parts such as a main board 70 on which a control unit and the like to be described later are mounted and a mirror driving unit 42 including a motor for changing the inclination angle of the concave mirror 41 are attached to the exterior case 54. Good. In the present embodiment, an attaching / detaching mechanism such as a screw hole, an opening for entering image light, and the like are further formed so that the image display device 30 can be attached / detached.

In the present embodiment, the video display device 30 is modularized so that it can be attached / removed integrally with the outer case 54 with screws or the like. Accordingly, for example, it is possible to configure so that only the video display device 30 can be exchanged without removing or disassembling the HUD device 1 itself, and the exchangeability of the video display device 30 which is the most fragile member can be improved. It can be greatly improved. Further, by adopting a configuration in which the video display device 30 is attached to the outside of the housing 50 of the HUD device 1, it is possible to improve heat dissipation and to obtain effects of reducing failure and deterioration due to heat.

In this embodiment, as described above, the configuration of a direct optical system that does not use an optical path folding mirror is adopted. Therefore, for example, a technique used in the prior art to suppress the temperature increase inside the housing 50 by using a cold mirror (a mirror that transmits infrared rays and reflects only visible light) as the optical path folding mirror. Can not take. Therefore, for example, an optical member such as a heat insulating film that cuts and reflects infrared rays is placed on the anti-glare plate 52 (image light emission surface side) or in front of the image display device 30 (LCD panel) (image light emission surface side). ) May be provided. As another infrared ray cutting means, for example, it is possible to use a polarizing plate that passes an S wave perpendicular to the incident surface and does not pass a P wave parallel to the incident surface.

FIG. 3 is a diagram showing an outline of an example of the mounting form of the video display device 30. Here, a state in which the modularized video display device 30 is disassembled into parts is shown in a perspective view. In the video display device 30, a display element 33 such as an LCD panel displays video by modulating light from the backlight based on a video signal input from the main board 70 via the flexible cable 34. The displayed video is output to the virtual image optical system (in this embodiment, the distortion correction lens 43 and the concave mirror 41 in FIG. 2) through the opening of the exterior case 54 in FIG. 2, and the virtual image that the driver 5 can visually recognize. Is generated.

As the light source element in the backlight, for example, a relatively inexpensive and highly reliable LED (Light Emitting Diode) light source 31a is used as a solid light source. The LED light source 31a is a surface-emitting type in order to increase the output. In the example of FIG. 3, it is mounted as an LED substrate. In this case, for example, the utilization efficiency of the divergent light is improved by using a technical device as will be described later.

The light emission efficiency with respect to the input power of the LED varies depending on the light emission color, but is about 20-30%, and most of the remainder is converted into heat. For this reason, the frame 35 to which the LED light source 31a is attached is provided with a heat radiation fin (heat sink 31b) made of a member having high thermal conductivity (for example, a metal member such as aluminum) to dissipate heat to the outside. Thereby, the effect which improves the luminous efficiency itself of the LED light source 31a can be acquired. In particular, red LEDs that are currently on the market that emit red light have a significantly reduced luminous efficiency when the junction temperature increases, and the chromaticity of the image also changes. Therefore, in order to prioritize the temperature reduction of the LED light source 31a, it is desirable to increase the cooling efficiency by increasing the area of the radiation fins in the heat sink 31b.

In order to efficiently guide the divergent light from the LED light source 31a to the display element 33, the light guide 32b is used in the example of FIG. In this case, in order to prevent adhesion of dust or the like, for example, it is desirable to cover the entire light guide 32b, the display element 33, and the like with exterior members 36a and 36b, and modularize the video display device 30.

Further, in the example of FIG. 3, a plurality of light funnels 32a made up of collimating lenses or the like are provided in order to take the divergent light from the LED light source 31a into parallel light. In each light funnel 32a, for example, the opening that takes in the divergent light from the LED light source 31a is a flat surface and is optically connected by inserting a medium between the LED light source 31a or condensing in a convex shape. Give action. Thereby, the diverging light is made as parallel light as possible, and the incident angle of the light incident on the interface of the light funnel 32a is reduced. As a result, since the divergence angle can be further reduced after passing through the light funnel 32a, it becomes easy to control the light source light directed to the display element 33 after being reflected by the light guide 32b.

Further, in order to improve the utilization efficiency of the divergent light from the LED light source 31a, polarization conversion is performed using a PBS (Polarizing Beam Beam Splitter) at the joint portion of the light funnel 32a and the light guide 32b to convert it into a desired polarization direction. Thereby, the efficiency of the incident light to the display element 33 can be improved. In this way, when the polarization direction of the light source light is aligned, it is desirable to use a material with less birefringence as the material of the light guide 32b. Thereby, when the direction of polarization rotates and passes through the display element 33, for example, it is possible to suppress the occurrence of a problem such as coloring during black display.

In this way, the light flux from the LED light source 31a with a reduced divergence angle is controlled by the light guide 32b, and is all provided on the slope of the light guide 32b (the surface on the exterior member 36a side in the example of FIG. 3). Reflects on the reflecting surface. Then, after being diffused by the diffusion plate 32c (diffuser) disposed between the display element 33 and the surface (outgoing surface) facing the total reflection surface in the light guide 32b, the light is transmitted to the display element 33 (LCD panel). Incident. In the example of FIG. 3, the light flux from the LED light source 31 a is diverged by disposing the diffusion plate 32 c between the light guide 32 b and the display element 33. However, the configuration is not limited to this. In place of the arrangement of the diffusion plate 32c, for example, a similar effect can be obtained by providing a fine uneven shape on the exit surface of the light guide 32b to provide a diffusion effect.

FIG. 4 is a diagram showing an outline of an example of a mounting form of the light guide 32b. Here, the cross-sectional shape of the portion including the light guide 32b and the light funnel 32a is schematically shown. The light flux (arrow in the figure) whose divergence angle is reduced by the light funnel 32a enters the incident surface 32b_1 of the light guide 32b via the joint portion 32d. At this time, the divergence angle in the vertical direction (vertical direction in FIG. 4) is controlled by the effect of the cross-sectional shape of the incident surface, and the light propagates efficiently in the light guide 32b.

The light source light incident from the incident surface 32b_1 is totally reflected by the total reflection prism provided on the opposing surface 32b_2 and travels toward the output surface 32b_3. The shape of the total reflection prism is different between the vicinity of the incident surface 32b_1 ("B portion" in the figure) and the vicinity of the emission surface 32b_3 ("A portion" in the figure). That is, it is divided into steps according to the divergence angles of the light beams incident on the respective surfaces, thereby controlling the angle of total reflection on the facing surface 32b_2. On the other hand, the light beam emitted from the emission surface 32b_3 and incident on the display element 33 in the subsequent stage is divided using the above-described division size on the opposite surface 32b_2 as a variable so that the light quantity distribution in the emission surface 32b_3 is uniform. The arrival position and the amount of energy after reflection of the light beam are controlled.

<Functional configuration of HUD device>
FIG. 5 is a functional block diagram showing an outline of an overall configuration example of the head-up display device according to the first embodiment of the present invention. The HUD device 1 mounted on the vehicle 2 includes various parts such as a vehicle information acquisition unit 10, a control unit 20, a video display device 30, a concave mirror 41, a mirror driving unit 42, and a speaker 60. In the example of FIG. 5, the shape of the vehicle 2 is displayed like a passenger car. However, the shape of the vehicle 2 is not particularly limited, and can be applied as appropriate to general vehicles.

The vehicle information acquisition unit 10 includes information acquisition devices such as various sensors, which will be described later, installed in each part of the vehicle 2, detects various events occurring in the vehicle 2, and relates to the driving situation at predetermined intervals. The vehicle information 4 is acquired and output by detecting and acquiring values of various parameters. The vehicle information 4 includes, for example, speed information, gear information, steering wheel steering angle information, lamp lighting information, external light information, distance information, infrared information, engine ON / OFF information, and camera video information of the vehicle 2 as illustrated. (Inside / outside the vehicle), acceleration gyro information, GPS (Global Positioning System) information, navigation information, vehicle-to-vehicle communication information, road-to-vehicle communication information, and the like may be included.

The control unit 20 has a function of controlling the operation of the HUD device 1 and is implemented by, for example, a CPU (Central Processing Unit) and software executed thereby. It may be implemented by hardware such as a microcomputer or FPGA (Field Programmable Gate Array). As shown in FIG. 1, the control unit 20 forms a video to be displayed as a virtual image by driving the video display device 30 on the basis of the vehicle information 4 acquired from the vehicle information acquisition unit 10, and forms the concave surface. The light is projected onto the windshield 3 by being reflected by the mirror 41.

As described above, the video display device 30 is a modular device including, for example, a projector and an LCD, and forms a video for displaying a virtual image based on an instruction from the control unit 20. This is projected and displayed. The mirror driving unit 42 adjusts the angle of the concave mirror 41 based on an instruction from the control unit 20 and adjusts the position of the virtual image display region in the vertical direction. The speaker 60 performs audio output related to the HUD device 1. For example, voice guidance of the navigation system or voice output when notifying the driver 5 of a warning or the like can be performed.

FIG. 6 is a diagram showing an outline of an example of a hardware configuration related to acquisition of vehicle information 4 in the head-up display device of the present embodiment. Here, a part of the hardware configuration of the vehicle information acquisition unit 10 and the control unit 20 will be mainly shown. The vehicle information 4 is acquired by an information acquisition device such as various sensors connected to the ECU 21 under the control of an ECU (Electronic Control Unit) 21, for example.

As these information acquisition devices, for example, a vehicle speed sensor 101, a shift position sensor 102, a steering wheel steering angle sensor 103, a headlight sensor 104, an illuminance sensor 105, a chromaticity sensor 106, a distance measuring sensor 107, an infrared sensor 108, an engine start sensor 109, acceleration sensor 110, gyro sensor 111, temperature sensor 112, road-to-vehicle communication wireless receiver 113, vehicle-to-vehicle communication wireless receiver 114, camera (inside the vehicle) 115, camera (outside the vehicle) 116, GPS receiver 117, and Each device includes a VICS (Vehicle Information and Communication System: a road traffic information communication system, registered trademark (hereinafter the same)) receiver 118 and the like. It is not always necessary to include all these devices, and other types of devices may be included. The vehicle information 4 that can be acquired by the provided device can be used as appropriate.

The vehicle speed sensor 101 acquires speed information of the vehicle 2. The shift position sensor 102 acquires current gear information of the vehicle 2. The steering wheel angle sensor 103 acquires steering wheel angle information. The headlight sensor 104 acquires lamp lighting information related to ON / OFF of the headlight. The illuminance sensor 105 and the chromaticity sensor 106 acquire external light information. The distance measuring sensor 107 acquires distance information between the vehicle 2 and an external object. The infrared sensor 108 acquires infrared information related to the presence / absence and distance of an object at a short distance of the vehicle 2. The engine start sensor 109 detects engine ON / OFF information.

The acceleration sensor 110 and the gyro sensor 111 acquire acceleration gyro information including acceleration and angular velocity as information on the posture and behavior of the vehicle 2. The temperature sensor 112 acquires temperature information inside and outside the vehicle. The road-to-vehicle communication wireless receiver 113 and the vehicle-to-vehicle communication wireless receiver 114 are respectively road-to-vehicle communication information received by road-to-vehicle communication between the vehicle 2 and roads, signs, signals, etc. The vehicle-to-vehicle communication information received by the vehicle-to-vehicle communication with another vehicle is acquired.

The camera (inside the vehicle) 115 and the camera (outside the vehicle) 116 respectively capture the moving image of the situation inside and outside the vehicle and acquire camera video information (inside / outside the vehicle). The camera (inside the vehicle) 115 captures, for example, the posture of the driver 5, the position of the eyes, the movement, and the like. By analyzing the obtained moving image, for example, it is possible to grasp the fatigue status of the driver 5, the position of the line of sight, and the like. In addition, the camera (outside the vehicle) 116 captures a situation around the vehicle 2 such as the front or rear. By analyzing the obtained video, for example, it is possible to grasp the presence or absence of moving objects such as other vehicles and people around the building, topography, road surface conditions (rain, snow, freezing, unevenness, etc.) It is.

The GPS receiver 117 and the VICS receiver 118 obtain GPS information obtained by receiving the GPS signal and VICS information obtained by receiving the VICS signal, respectively. It may be implemented as a part of a car navigation system that acquires and uses these pieces of information.

FIG. 7 is a functional block diagram showing details of a configuration example of the head-up display device of the present embodiment. The example of FIG. 7 shows a case where the video display device 30 is a projector, and the video display device 30 includes, for example, each unit such as a light source 31, an illumination optical system 32, and a display element 33.

The light source 31 is a member that generates illumination light for projection and constitutes a backlight. For example, a high-pressure mercury lamp, a xenon lamp, an LED light source, a laser light source, or the like can be used. It is desirable to use a solid light source with a long product life. For example, it is desirable to perform polarization conversion using an PBS provided with optical means for reducing the divergence angle of light for an LED light source with little change in light output with respect to changes in ambient temperature. In the present embodiment, as shown in FIG. 3, the light source 31 is configured by the LED light source 31a and the heat sink 31b. The light source 31 is arranged or controlled so that the incident direction of light with respect to the display element 33 described later efficiently enters the entrance pupil of the concave mirror 41.

The illumination optical system 32 is an optical system that collects the illumination light generated by the light source 31 and irradiates the display element 33 with more uniform illumination light. In the present embodiment, as shown in FIG. 3, the illumination optical system 32 is configured by the light funnel 32a, the light guide 32b, and the diffusion plate 32c.

The display element 33 is an element that generates an image to be projected. For example, a transmissive liquid crystal panel, a reflective liquid crystal panel, a DMD (Digital Micromirror Device) (registered trademark) panel, or the like can be used. A polarizing plate is disposed on each of the light incident surface (that is, the light source 31 and the illumination optical system 32 side) and the light emitting surface (that is, the distortion correction lens 43 and the concave mirror 41 side in FIG. 1) of the display element 33 to display an image. It is desirable to increase the light contrast ratio. A high contrast ratio can be obtained by using an iodine-based polarizing plate having a high degree of polarization as the polarizing plate provided on the light incident surface. On the other hand, by using a dye-based polarizing plate provided on the light emitting surface, high reliability can be obtained even when external light is incident or the ambient temperature is high.

When an LCD panel is used as the display element 33, in particular, when the driver 5 is wearing polarized sunglasses, a specific polarization may be blocked and an image may not be visible. In order to prevent this, a λ / 4 plate is arranged in front of the polarizing plate arranged on the light exit surface of the LCD panel (that is, the distortion correcting lens 43 and the concave mirror 41 side), and the image is aligned in a specific polarization direction. It is desirable to convert light to circularly polarized light.

More specifically, the control unit 20 includes each unit such as an ECU 21, an audio output unit 22, a nonvolatile memory 23, a memory 24, a light source adjustment unit 25, a distortion correction unit 26, a display element driving unit 27, and a mirror adjustment unit 28. Have.

As shown in FIG. 6, the ECU 21 acquires the vehicle information 4 via the vehicle information acquisition unit 10, and records, stores, and reads the acquired information in the nonvolatile memory 23 and the memory 24 as necessary. To do. The nonvolatile memory 23 may store setting information such as setting values and parameters for various controls. In addition, the ECU 21 generates video data related to a virtual image displayed as the HUD device 1 by executing a dedicated program. The audio output unit 22 outputs audio information via the speaker 60 as necessary. The light source adjustment unit 25 adjusts the light emission amount of the light source 31 of the video display device 30. When there are a plurality of light sources 31, they may be controlled individually.

The distortion correction unit 26 corrects distortion generated when the video generated by the ECU 21 is projected onto the windshield 3 of the vehicle 2 by the video display device 30 by image processing. This distortion may include, for example, distortion of an image caused by the curvature of the windshield 3, distortion caused by a minute positional shift when the module of the image display device 30 is attached, and the like. The display element drive unit 27 sends a drive signal corresponding to the video data corrected by the distortion correction unit 26 to the display element 33 to generate an image to be projected. When the position of the virtual image display area itself needs to be adjusted, the mirror adjustment unit 28 changes the angle of the concave mirror 41 via the mirror driving unit 42 to move the virtual image display area up and down.

<Configuration of virtual image optical system>
FIG. 8 is a diagram showing an outline of a configuration example of an optical system that displays a virtual image in the HUD device 1 and miniaturization of the device. FIG. 8A is a diagram showing an outline of the basic configuration of the virtual image optical system in the HUD device 1, and schematically shows the shape of the vertical section of the HUD device 1. Here, for the sake of simplification of explanation, the illustration of the distortion correction lens 43 for correcting aberration and distortion is omitted. The concave mirror 41 is simply displayed as a plane mirror.

In the example of FIG. 8, an LCD panel is used as the display element 33 of the video display device 30, and a configuration in which a light source 31 that is a backlight and a concave mirror 41 are arranged as a basic configuration is housed in the housing 50. It shows the state being done. Each element of the basic configuration is arranged at a position where an image displayed on the display element 33 is reflected by the concave mirror 41 and visually recognized as a virtual image. In addition, image lights generated from the images at the upper, middle, and lower ends of the screen of the display element 33 are indicated by dotted arrows as image lights R ₁ , R ₂ , and R ₃ , respectively. Here, as shown in the drawing, when each image light is reflected by the concave mirror 41, it is a design constraint to arrange each element so that the image light is not blocked by interfering with the display element 33. .

FIGS. 8A to 8C show states where the horizontal distance Z at the center of each of the concave mirror 41 and the display element 33 is changed as a parameter in consideration of the above design constraints. . FIG. 8A to FIG. 8C show a configuration in which the distance Z gradually decreases from Z ₁ to Z ₃ as shown in the figure, and accordingly, the concave mirror 41 is displaced from the horizontal plane. The angle also gradually increases from α ₁ to α ₃ . Similarly, the vertical dimension of the concave mirror 41 is also gradually increased.

When the parameter of the distance Z is changed, the height and depth of the HUD device 1 (more specifically, the housing 50) change, and the volume also changes accordingly. That is, when the distance Z is reduced, as shown in FIG. 8C, the height of the HUD device 1 is slightly increased while the depth can be greatly reduced. As a result, by configuring the distance Z to be small, the volume of the HUD device 1 (housing 50) can be further reduced and downsized.

On the other hand, for example, when the distance Z is decreased (distance Z ₃ ) as shown in FIG. 8C, the distance from the upper end of the display element 33 to the upper end of the concave mirror 41 (corresponding to the image light R ₁ ) is displayed. the difference between the distance from the lower end of the element 33 to the lower end of the concave mirror 41 (corresponding to the image light R ₃₎ increases. That is, when the distance Z is reduced, the volume of the HUD device 1 can be reduced, but the distortion and aberration of the virtual image generated in the concave mirror 41 are increased. On the other hand, at least the arrangement position of the display element 33 or the like is moved in the direction of the arrow shown in FIG. 8C within a range that does not interfere with the image light (particularly the image light R ₃ ). It is desirable that the distance from the concave mirror 41 be as uniform as possible.

Furthermore, in the present embodiment, as described above, the distortion and aberration are arranged by disposing the distortion correction lens 43 for correcting the distortion of the virtual image and the aberration generated in the virtual image between the display element 33 and the concave mirror 41. Perform the correction.

FIG. 9 is a diagram showing an outline of an example of distortion and aberration correction by the distortion correction lens 43. As shown in the figure, a display element 33 (object point) is placed inside the focal point F (focal length f) with respect to a point O on the optical axis of the concave mirror 41, thereby providing a virtual image (in the figure) by the concave mirror 41. Then, it can be obtained by an arrow figure). In the figure, for convenience of explanation, the concave mirror 41 is regarded as a convex lens having the same positive refractive power, and the relationship between an object point and a convex lens (indicated in the figure as the concave mirror 41 for convenience of explanation) and a generated virtual image is shown. ing.

In the present embodiment, as described above, the distortion correction lens 43 is disposed in order to reduce distortion and aberration generated in the concave mirror 41. In this embodiment, the optical element is a transmissive optical lens, but is not limited to a lens and may be a concave mirror. The distortion correction lens 43 is
(1) When the image light from the display element 33 enters the reflection surface of the distortion correction lens 43 as a telecentric light beam, the refractive power of the distortion correction lens 43 (optical lens or concave mirror) becomes almost zero (2) When the image light from the display element 33 diverges and enters the distortion correction lens 43, the distortion correction lens 43 has a positive refractive power. (3) The image light from the display element 33 is condensed to correct the distortion. When entering the lens 43, the distortion correcting lens 43 has a negative refractive power so as to control the direction (angle and position) of the light beam incident on the concave mirror 41. Thereby, the distortion aberration of the virtual image generated by the concave mirror 41 is corrected. Further, when the distortion correction lens 43 is formed of a transmission type optical lens, a virtual image is generated due to the interaction between the light incident surface (display element 33 side) and the light output surface (concave mirror 41 side). Aberrations related to image performance are corrected.

At this time, the distance a from the display element 33 to the concave mirror 41 and the distance b from the concave mirror 41 to the virtual image are, as described above, between the upper and lower ends of the virtual image due to the inclination and curvature of the windshield 3. Will be different. Thereby, the image magnification of the virtual image visually recognized by the driver 5 is different between the upper end portion and the lower end portion.

On the other hand, in the present embodiment, the display element 33 is tilted with respect to the optical axis of the concave mirror 41 as shown in FIG. 9, so that the image magnification M ′ = b ′ / a ′ at the upper end of the virtual image and the virtual image are obtained. The image magnification M at the lower end is made substantially equal to b / a. Thereby, distortion due to the inclination of the windshield 3 or the like is reduced.

In the present embodiment, the average curvature radius of the cross-sectional shape in the vertical direction of the distortion correction lens 43 and the average curvature radius of the cross-sectional shape in the horizontal direction are set to different values. Thereby, the distortion aberration caused by the optical path difference caused by the difference between the curvature radius in the vertical direction and the curvature radius in the horizontal direction of the windshield 3 and the aberration that deteriorates the imaging performance of the virtual image are corrected. In the HUD device 1 that obtains a virtual image by directly reflecting video light on the windshield 3, correction of aberrations caused by the optical path difference caused by the difference between the curvature radius in the vertical direction and the curvature radius in the horizontal direction of the windshield 3 is as follows. It is most important in securing the imaging performance of virtual images.

Specifically, by using a free-form surface shape as the shape of the distortion correction lens 43, a decrease in the imaging performance of the virtual image due to the difference in the radius of curvature of the windshield 3 as described above is reduced. Conventional optical designs have used aspherical shapes that define the shape of lens surfaces and mirror surfaces as a function of distance r from the optical axis. The aspherical shape is expressed as the following equation.

On the other hand, in the present embodiment, a free curved surface shape that can define the surface shape as a function of absolute coordinates (x, y) from the optical axis is used. The free-form surface shape is represented by the following equation.

In this way, by using the distortion correction lens 43 and controlling its cross-sectional shape and arrangement position, the distortion and aberration of the virtual image generated by the concave mirror 41 can be corrected. However, for that purpose, it is a premise that high positioning accuracy is secured for the optical members such as the concave mirror 41 and the distortion correction lens 43.

In this regard, for example, in the configuration of the HUD device 1 shown in FIG. 2B, each member such as the exterior lid portion 51, the exterior case 54, and the optical component holding member 53 constituting the housing 50 is made resistant to heat. Problems may arise when formed using materials that do not have high rigidity and dimensional accuracy. For example, the positional relationship between the concave mirror 41 and the distortion correction lens 43 is designed due to the effects of processing accuracy and work accuracy when the HUD device 1 is manufactured and attached to the vehicle 2, and expansion and deformation due to heat during use. This may cause a deviation. As a result, the accuracy of correcting distortion and aberration by using the distortion correction lens 43 also decreases.

Therefore, in the present embodiment, in the configuration of the HUD device 1 shown in FIG. 2B, at least the optical component holding member 53 that holds the concave mirror 41 and the distortion correction lens 43 is provided with high heat resistance, high rigidity, and high dimensions. It is formed of a material having the characteristic of accuracy. Specifically, for example, unsaturated polyester resin such as BMC (Bulk Molding Compound), polycarbonate with glass filler, or the like is used. In particular, BMC is used in this embodiment because BMC has thermosetting properties and can be complicatedly formed by a mold. In this case, the members constituting the housing 50 such as the outer case 54 and the outer lid portion 51 that store the optical component holding member 53 mainly have a dustproof function. Therefore, it is not always necessary to use the material as described above, and an appropriate material can be used in consideration of the manufacturing cost.

By holding the concave mirror 41 and the distortion correction lens 43 by the optical component holding member 53 formed of the material as described above, the concave mirror 41 and the distortion can be obtained even under severe use environment such as high temperature and vibration in the vehicle 2. The positional relationship with the correction lens 43 can be maintained with high accuracy. In addition, since the relative positional relationship between the concave mirror 41 and the distortion correction lens 43 is a three-dimensional complicated torsional relationship, the concave mirror 41 and the distortion correction lens 43 are configured and held as a single unit. It is difficult. Therefore, in this embodiment, the concave mirror 41 and the distortion correction lens 43 are individually held by the optical component holding member 53.

The optical holding member 53 realizes and maintains the positional relationship between the concave mirror 41 and the distortion correction lens 43 with high accuracy even if the positional relationship between the concave mirror 41 and the distortion correcting lens 43 is in the three-dimensional torsional relationship as described above. Is possible. That is, the concave mirror 41 and the distortion correction lens 43 are held by the optical holding member 53 which is a single intervening part formed of a material having characteristics of high heat resistance, high rigidity, and high dimensional accuracy. It is possible to maintain the positional relationship with high accuracy. In the present embodiment, the shape of the optical holding member 53 having such characteristics is also optimized so that it can be molded as a single part by resin mold molding. .

In the present embodiment, as described above, the video display device 30 is modularized so that it can be easily attached and detached. As a result, there is a possibility that a slight positional deviation may occur when the video display device 30 is mounted. This deviation is corrected or corrected by, for example, image processing in the distortion correcting unit 26 of the control unit 20 shown in FIG. Adjustments can be made.

<Processing content of HUD device>
FIG. 10 is a flowchart outlining an example of the initial operation of the head-up display device of the present embodiment. When the ignition switch is turned on in the stopped vehicle 2 and the power of the HUD device 1 is turned on (S01), the HUD device 1 first starts the vehicle information acquisition unit 10 based on an instruction from the control unit 20. Thus, vehicle information is acquired (S02). Then, the control unit 20 calculates a suitable brightness level based on external light information acquired by the illuminance sensor 105, the chromaticity sensor 106, and the like in the vehicle information 4 (S03), and the light source adjustment unit 25 calculates the light source 31. Is set so that the calculated brightness level is obtained (S04). For example, when the outside light is bright, the brightness level is set high, and when the outside light is dark, the brightness level is set low.

Thereafter, the ECU 21 determines and generates a video (for example, an initial image) to be displayed as a virtual image (S05), and performs a process of correcting the distortion by the distortion correction unit 26 for the generated video (S06). The display element 33 is driven and controlled by the element driving unit 27 to form a projected image (S07). Thereby, an image | video is projected on the windshield 3, and the driver | operator 5 comes to be able to visually recognize a virtual image.

When the HUD device 1 as a whole completes starting and starting of each part including the series of initial operations described above, a HUD-ON signal is output. The controller 20 determines whether or not this signal has been received (S08). . If not received, the HUD-ON signal is further waited for a predetermined time (S09), and the HUD-ON signal waiting process (S09) is repeated until it is determined in step S08 that the HUD-ON signal has been received. If it is determined in step S08 that the HUD-ON signal has been received, normal operation of the HUD device 1 described later is started (S10), and a series of initial operations are terminated.

FIG. 11 is a flowchart showing an outline of an example of normal operation of the head-up display device of the present embodiment. Also in the normal operation, the basic processing flow is substantially the same as the initial operation shown in FIG. First, the HUD device 1 acquires vehicle information by the vehicle information acquisition unit 10 based on an instruction from the control unit 20 (S21). And the control part 20 performs a brightness level adjustment process based on the external light information acquired by the illumination intensity sensor 105, the chromaticity sensor 106, etc. among the vehicle information 4 (S22).

FIG. 12 is a flowchart showing an outline of an example of brightness level adjustment processing of the head-up display device of the present embodiment. When the brightness level adjustment process is started, first, a suitable brightness level is calculated based on the acquired outside light information (S221). Then, by comparing with the currently set brightness level, it is determined whether or not the brightness level needs to be changed (S222). If no change is necessary, the brightness level adjustment process is terminated. On the other hand, when the change is necessary, the light source adjustment unit 25 controls the light emission amount of the light source 31 to set the brightness level after the change (S223), and the brightness level adjustment process is ended. . In step S222, even when there is a difference between the preferred brightness level calculated in step S221 and the currently set brightness level, the brightness level is only when the difference is equal to or greater than a predetermined threshold. It may be determined that the change is necessary.

Returning to FIG. 11, the ECU 21 then changes the video to be displayed as a virtual image from the current one as necessary based on the latest vehicle information 4 acquired in step S21, and determines and generates the changed video. (S23). In addition, the pattern which changes a display content based on the vehicle information 4 can have many things according to the content of the acquired vehicle information 4, those combinations, etc. For example, when the speed information changes, the value of the speed display that is displayed at all times is changed, the guidance arrow graphic is displayed / erased based on the navigation information, and the arrow shape and display position are changed. There may be various patterns, such as when performing.

Thereafter, in the present embodiment, adjustment / correction processing is performed to maintain visibility, appropriateness of display contents, and the like according to the traveling state of the vehicle 2. First, when it is necessary to adjust the position of the virtual image display area itself, the angle of the concave mirror 41 is changed via the mirror driving unit 42 to perform mirror adjustment processing for moving the virtual image display area up and down (S24). ). Thereafter, a vibration correction process for correcting the display position of the image in the display area with respect to the vibration of the vehicle 2 is performed (S25). Thereafter, the distortion correction unit 26 performs distortion correction processing on the adjusted / corrected image (S26), and then the display element driving unit 27 drives and controls the display element 33 to form a projected image ( S27).

When the power is turned off when the vehicle 2 is stopped during the series of normal operations described above, a HUD-OFF signal is output to the HUD device 1. It is determined whether or not this signal has been received (S28). If the HUD-OFF signal has not been received, the process returns to step S21, and a series of normal operations are repeated until the HUD-OFF signal is received. If it is determined that the HUD-OFF signal has been received, a series of normal operations is terminated.

As described above, according to the HUD device 1 according to the first embodiment of the present invention, a direct optical system including only the concave mirror 41 is used without using an optical path folding mirror in the virtual image optical system. Then, in order to correct the distortion and aberration of the virtual image generated by the concave mirror 41, a distortion correction lens 43 is arranged between the concave mirror 41 and the display element 33. By taking such a configuration, the HUD device 1 can be further reduced in size.

In the present embodiment, the concave mirror 41 and the distortion correction lens 43 are further held by an optical component holding member 53 formed of a material having high heat resistance, high rigidity, and high dimensional accuracy. Thereby, the positional relationship between the concave mirror 41 and the distortion correction lens 43 can be maintained with high accuracy. Further, the light source 31, the illumination optical system 32, and the display element 33 (LCD panel or the like) are modularized as the video display device 30 and are configured to be detachable. As a result, it is possible to improve the replacement performance of the video display device 30 that is likely to fail, and to improve the heat dissipation.

(Embodiment 2)
In the first embodiment described above, as shown in FIG. 2B, the concave mirror 41 and the distortion correction lens 43 are held by the optical component holding member 53 and are housed in the outer case 54 and the outer lid portion 51. Have taken. At this time, in order to maintain the positional relationship between the concave mirror 41 and the distortion correction lens 43 with high accuracy, at least the optical component holding member 53 is formed of a material having high heat resistance, high rigidity, and high dimensional accuracy such as BMC.

On the other hand, in the optical component holding member 53 as shown in FIG. 2B, there may be a case where sufficient rigidity cannot be ensured depending on the shape. For example, as shown in FIG. 2B, when holding the concave mirror 41 and the distortion correcting lens 43 in the substantially vertical direction at both ends of the optical component holding member 53, the shape seen from the side surface of the optical component holding member 53. Is generally concave (or U-shaped). In this shape, it can be said that it is a shape which is easy to produce the shape of the shape which bends in a dent part, and cannot ensure high rigidity.

On the other hand, in order to realize high rigidity, for example, when the optical component holding member 53 as shown in FIG. Gradually, not only the concave mirror 41 and the distortion correction lens 43 are held, but also a function as an outer case for housing them can be achieved. Therefore, in the HUD device 1 according to the second embodiment of the present invention, the members that hold the optical components of the concave mirror 41 and the distortion correction lens 43 are formed as members that also function as an exterior case.

FIG. 13 is a diagram showing an outline of an example of a mounting form of the head-up display device according to the second embodiment of the present invention. Here, in the HUD device 1 having the same configuration as that shown in the first embodiment, the optical component holding member 53 and the exterior case 54 in the example of FIG. 2B are integrated physically and functionally. A component holding outer case 55 is used. That is, the concave mirror 41 and the distortion correcting lens 43 are directly held on the optical component holding outer case 55 having a function as an outer case. The optical component holding outer case 55 is formed of a material having characteristics of high heat resistance, high rigidity, and high dimensional accuracy, such as BMC, like the optical component holding member 53 in FIG.

As a result, the same effect as that obtained by the configuration of the HUD device 1 of the first embodiment, such as maintaining the positional relationship between the concave mirror 41 and the distortion correction lens 43 with high accuracy, can be obtained, and the number of parts can be further reduced. To simplify the configuration.

As mentioned above, the invention made by the present inventor has been specifically described based on the embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say. For example, the above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to the one having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. . Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

The present invention can be used for a head-up display device that projects an image on a transparent glass element or the like.

DESCRIPTION OF SYMBOLS 1 ... HUD apparatus, 2 ... Vehicle, 3 ... Wind shield, 4 ... Vehicle information, 5 ... Driver,
10 ... Vehicle information acquisition unit,
DESCRIPTION OF SYMBOLS 20 ... Control part, 21 ... ECU, 22 ... Audio | voice output part, 23 ... Nonvolatile memory, 24 ... Memory, 25 ... Light source adjustment part, 26 ... Distortion correction part, 27 ... Display element drive part, 28 ... Mirror adjustment part,
DESCRIPTION OF SYMBOLS 30 ... Image display apparatus, 31 ... Light source, 31a ... LED light source, 31b ... Heat sink, 32 ... Illumination optical system, 32a ... Light funnel, 32b ... Light guide, 32b_1 ... Incident surface, 33 ... Display element, 33b_2 ... Opposite surface 32b_3... Exit surface, 32c... Diffuser plate, 32d... Junction, 33... Display element, 34 .. flexible cable, 35 ... frame, 36a, 36b.
41 ... concave mirror, 42 ... mirror drive unit, 43 ... distortion correction lens,
DESCRIPTION OF SYMBOLS 50 ... Housing | casing, 51 ... Exterior lid part, 52 ... Anti-glare board, 53 ... Optical component holding member, 54 ... Exterior case, 55 ... Optical component holding exterior case,
60 ... Speaker,
70 ... main board,
DESCRIPTION OF SYMBOLS 101 ... Vehicle speed sensor, 102 ... Shift position sensor, 103 ... Steering wheel angle sensor, 104 ... Headlight sensor, 105 ... Illuminance sensor, 106 ... Chromaticity sensor, 107 ... Ranging sensor, 108 ... Infrared sensor, 109 ... Engine start 110, acceleration sensor, 111 ... gyro sensor, 112 ... temperature sensor, 113 ... wireless receiver for road-to-vehicle communication, 114 ... wireless receiver for vehicle-to-vehicle communication, 115 ... camera (inside the vehicle), 116 ... camera (outside the vehicle) 117 ... GPS receiver, 118 ... VICS receiver

Claims (14)

1. A head-up display device for a vehicle,
   A video display device that has a light source and a display element, displays video on the display element, and generates and emits video projection light;
   A virtual image optical system that displays a virtual image in front of the vehicle by reflecting the video projection light emitted from the video display device with a windshield or a combiner of the vehicle;
   Have
   The virtual image optical system includes a mirror and an optical element,
   The optical element is arranged between the video display device and the mirror, and is configured to correct distortion of the virtual image by the shape of the mirror and the shape of the optical element,
   The mirror and the optical element are each positioned and held by a holding member formed of a predetermined material,
   The holding member is a head-up display device housed in a housing.
2. The head-up display device according to claim 1,
   The head-up display device, wherein the mirror is a concave mirror.
3. The head-up display device according to claim 1,
   The head-up display device, wherein the optical element is configured to correct distortion of the virtual image obtained corresponding to the viewpoint position of the driver.
4. A head-up display device for a vehicle,
   A video display device having a light source and a display element, and generating video display light on the display element;
   A virtual image optical system that displays a virtual image in front of the vehicle by reflecting light emitted from the video display device with a windshield or a combiner;
   Have
   The virtual image optical system includes a mirror and an optical element,
   The optical element is arranged between the video display device and the mirror, and is configured to correct distortion of the virtual image by the shape of the mirror and the shape of the optical element,
   The head-up display device, wherein the mirror and the optical element are each positioned and held by an outer case that is formed of a predetermined material and forms at least a part of the housing.
5. The head-up display device according to claim 4,
   The head-up display device, wherein the mirror is a concave mirror.
6. The head-up display device according to claim 4,
   The head-up display device, wherein the optical element is configured to correct distortion of the virtual image obtained corresponding to the viewpoint position of the driver.
7. The head-up display device according to claim 1 or 4,
   The head-up display device, wherein the predetermined material is BMC or polycarbonate with a glass filler.
8. The head-up display device according to claim 1 or 4,
   The video display device is a head-up display device that is detachable integrally with the housing.
9. The head-up display device according to claim 1 or 4,
   A head-up display provided with an opening through which light from the virtual image optical system passes in the housing, an optical member that reflects infrared light on the virtual image optical system side of the display element, or a polarizing plate that passes only S waves. apparatus.
10. The head-up display device according to claim 1 or 4,
    The video display device is a head-up display device arranged to be inclined with respect to the optical axis of the mirror.
11. The head-up display device according to claim 1,
    A head-up display device in which the mirror and the optical element having a three-dimensional twist relationship are held by a single holding member.
12. The head-up display device according to claim 4,
    A head-up display device in which the mirror and the optical element having a three-dimensional twist relationship are held in the outer case.
13. The head-up display device according to claim 4,
    The mirror held by the holding member or the outer case has an angle adjustment mechanism,
    The said mirror adjusts the angle of the said mirror by the said angle adjustment mechanism, adjusts the position projected on a windshield, and makes it possible to adjust the position of the virtual image which the driver sees up and down.
14. The head-up display device according to claim 1 or 2,
    A head-up display device in which the average curvature radius of the vertical cross-sectional shape of the optical element is different from the average curvature radius of the horizontal cross-sectional shape.

Images