Head-up display

Abstract

To provide a head-up display capable of easily performing three-dimensional display.SOLUTION: A head-up display 1 comprises: a main display device 11 that emits main display light L1; reflection mirrors 12, 13 that include reflection surfaces 12a, 13a and transmission surfaces 12b, 13b and allow a driver 4 to view the main display light L1 as a main virtual image V1 at a front side of a windshield 3 by reflecting the main display light L1 toward the windshield 3 at the reflection surfaces 12a, 13a; and sub-display devices 20, 30 that allow the driver 4 to view reflected sub-display light L2, L3 as sub-virtual images V2, V3 at a rear side of the main virtual image V1 by emitting the sub-display light L2, L3 through the transmission surfaces 12b, 13b toward the windshield 3.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a head-up display for vehicles and the like.

Background Art

[0002] A head-up display (HUD) displays necessary information for driving as a virtual image in association with the actual scene that a driver can visually recognize, so that the driver can intuitively understand the information. Thus, the HUD allows the driver to visually recognize information without diverting the line of sight from the front. Nowadays, there is also a known HUD that can be three-dimensionally represented by giving a sense of depth to the display. For example, there is a technology that allows the left and right eyes to visually recognize different images and enables stereoscopic vision with the naked eye.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the above-described technology, in order to make different display lights enter the left and right eyes, it is required to form a high-resolution image. Therefore, the above-described technology requires a large memory capacity, a high-performance GPU (Graphics Processing Unit), etc., so the component cost is high. When there are cost constraints, it has been difficult to mount a HUD capable of three-dimensional display on vehicles and the like.

[0005] The present disclosure has been made in consideration of such circumstances, and an object thereof is to provide a head-up display that can easily perform three-dimensional display.

Means for Solving the Problems

[0006] Book The disclosed head-up display, in order to solve the above-mentioned problems, includes a main display unit that emits main display light, a first reflecting surface, and a first transmissive surface which is the surface opposite to the first reflecting surface, and a first reflector which reflects the main display light on the first reflecting surface toward a projection member so that the main display light reflected by the projection member is visible to a viewer positioned behind the projection member as a main virtual image in front of the projection member, and a first sub-display unit which emits first sub-display light that passes through the first transmissive surface toward the projection member so that the first sub-display light reflected by the projection member is visible to the viewer as a first sub-virtual image in front of the projection member and behind the main virtual image, and the main display unit and the first reflector A second reflector is positioned between the two lanes of the vehicle and has a second reflective surface and a second transmissive surface opposite to the second reflective surface, and reflects the main display light toward the first reflective surface at the second reflective surface; and a second sub-display unit emits a second sub-display light that passes through the second transmissive surface toward the first reflective surface, thereby causing the viewer to perceive the second sub-display light reflected by the first reflective surface and the projection member as a second sub-virtual image between the main virtual image and the first sub-virtual image, wherein the second sub-display unit emits the second sub-display light such that the second sub-virtual image is positioned closer to the center of the display area of ​​the main virtual image compared to the first sub-virtual image, and when another vehicle approaches from behind in an adjacent lane, the first sub-virtual image on the adjacent lane side is displayed, and thereafter, The aforementioned When another vehicle overtakes the aforementioned vehicle, the second sub-virtual image on the adjacent lane side is displayed. [Effects of the Invention]

[0007] The head-up display of this disclosure enables easy three-dimensional display. [Brief explanation of the drawing]

[0008] [Figure 1] A diagram showing an example of the HUD system configuration in this embodiment. [Figure 2] A diagram showing an example of a virtual image displayed in the display area. [Figure 3] A conceptual diagram illustrating the device configuration of a HUD. [Figure 4] A diagram illustrating the device configuration of a planar mirror and a sub-display on the planar mirror side, and a concave mirror and a sub-display on the concave mirror side. [Figure 5] A diagram conceptually illustrating the device configuration of a HUD as a modified example of a HUD. [Modes for carrying out the invention]

[0009] Embodiments of the head-up display of this disclosure will be described with reference to the accompanying drawings. The head-up display of this disclosure can be applied to head-up displays mounted on vehicles such as automobiles and motorcycles, as well as on ships, agricultural machinery, and construction machinery. In this embodiment, an example will be described in which the head-up display is mounted on a vehicle and displays required information based on various information acquired from the vehicle.

[0010] Figure 1 shows an example of the system configuration of HUD1 in this embodiment.

[0011] Figure 2 shows examples of virtual images V1, V2, and V3 displayed in display areas D1, D2, and D3.

[0012] Figure 3 is a conceptual diagram illustrating the device configuration of HUD1.

[0013] Figure 4 is a diagram illustrating the device configuration of the planar mirror 12 and the planar mirror-side sub-display 20, and the concave mirror 13 and the concave mirror-side sub-display 30.

[0014] In the following explanation, "front," "back," "up," "down," "right," and "left" follow the definitions "Fr.", "Re.", "To.", "Bo.", "R," and "L" in Figures 1 and 2.

[0015] HUD1 is mounted in the instrument panel of vehicle 2. HUD1 includes a main display unit 11, a flat mirror 12 (second reflector), a concave mirror 13 (first reflector), a flat mirror-side sub-display unit 20 (second sub-display unit), a concave mirror-side sub-display unit 30 (first sub-display unit), a housing 15, and a control unit 40.

[0016] The HUD1 projects the display lights L1, L2, and L3 emitted by the main display unit 11, the planar mirror-side sub-display unit 20, and the concave mirror-side sub-display unit 30 onto the windshield 3 (projection member) on the vehicle 2. The driver 4 (viewer) of the vehicle 2, positioned behind the windshield 3, sees the reflected light of the display lights L1, L2, and L3 on the windshield 3 as virtual images V1, V2, and V3 in front of the windshield 3. The virtual images V1, V2, and V3 are displayed in virtual display areas D1, D2, and D3, respectively, with the actual scenery visible to the driver 4 through the windshield 3 (in front of the windshield 3) as the background. The display areas D1, D2, and D3 are, for example, two-dimensional rectangular display surfaces.

[0017] The main display unit 11 is, for example, a TFT (Thin Film Transistor) type liquid crystal display, an organic EL (Electroluminescence) display, or a projector and a screen that constitutes the display surface. The main display unit 11 displays the design related to the main virtual image V1 (virtual image V1) and emits the main display light L1 related to the design toward the plane mirror 12.

[0018] The plane mirror 12 is located behind the main display 11 and is disposed between the main display 11 and the concave mirror 13. The plane mirror 12 is a so-called half mirror having a reflecting surface 12a (second reflecting surface) and a transmitting surface 12b (second transmitting surface) which is the surface opposite to the reflecting surface 12a. As shown in FIG. 4, the plane mirror 12 has a black printing layer 12c. The black printing layer 12c forms a transmitting region 12d and a non-transmitting region 12e on the transmitting surface 12b. The black printing layer 12c is provided for the plane mirror 12 to form plane mirror side sub-display light L2 (sub-display light L2, second sub-display light) related to the design of the plane mirror side sub-virtual image V(2 sub-virtual image V2). That is, the light emitted from the plane mirror side sub-display 20 becomes plane mirror side sub-display light L2 related to the design of the plane mirror side sub-virtual image V2 by passing through the transmitting region 12d of the black printing layer 12c.

[0019] The concave mirror 13 is disposed behind the plane mirror 12. The concave mirror 13 is a so-called half mirror having a concave reflecting surface 13a (first reflecting surface) and a transmitting surface 13b (first transmitting surface) which is the surface opposite to the reflecting surface 13a. The reflecting surface 13a has a function as a magnifying glass, magnifies the designs related to the display lights L1 and L2, and reflects them toward the windshield 3 side. As shown in FIG. 4, the concave mirror 13 has a black printing layer 13c. The black printing layer 13c forms a transmitting region 13d and a non-transmitting region 13e on the transmitting surface 13b. The black printing layer 13c is provided for the concave mirror 13 to form concave mirror side sub-display light L3 (sub-display light L3, first sub-display light) related to the design of the concave mirror side sub-virtual image V3 (sub-virtual image V3). That is, the light emitted from the concave mirror side sub-display 30 becomes concave mirror side sub-display light L3 related to the design of the concave mirror side sub-virtual image V3 by passing through the transmitting region 13d of the black printing layer 13c.

[0020] The transmitting regions 12d and 13d form the sub-display lights L2 and L3 respectively so that the plane mirror side sub-virtual image V2 is disposed closer to the center (closer to the center in the left-right, up-down directions) of the display region D1 of the main virtual image V1 than the concave mirror side sub-virtual image V3.

[0021] The planar mirror side sub-display 20 (sub-display 20) is two sub-displays 20 symmetrically arranged at the left and right ends of the planar mirror 12. The planar mirror side sub-display 20 is arranged on the transmission surface 12b side of the planar mirror 12. The planar mirror side sub-display 20 emits sub-display light L2 on the planar mirror side through the transmission surface 12b of the planar mirror 12 and towards the reflection surface 13a of the concave mirror 13.

[0022] The planar mirror side sub-display 20 includes an LED (Light Emitting Diode) 21, a circuit board 22, a condenser lens 23, and a housing 24.

[0023] The LED 21 is a full-color LED in which light sources of three colors, RGB (red, green, and blue), are sealed in one package, and the brightness and color can be varied by changing the brightness of each light source. The circuit board 22 controls the lighting and brightness of each LED 21 based on instructions from the control unit 40. The condenser lens 23 condenses the light emitted by the LED 21 and emits it parallel. The condenser lens 23 may be a diffusion member that diffuses the light of the LED 21. The housing 24 is a box-shaped member that houses the LED 21 and the circuit board 22 in the rear-end opening and the condenser lens 23 in the front-end opening.

[0024] The concave mirror side sub-display 30 (sub-display 30) is two sub-displays 30 symmetrically arranged at the left and right ends of the concave mirror 13. The concave mirror side sub-display 30 is arranged on the transmission surface 13b side of the concave mirror 13. The concave mirror side sub-display 30 emits sub-display light L3 on the concave mirror side through the transmission surface 13b and towards the windshield 3. The concave mirror side sub-display 30 includes an LED 31, a circuit board 32, a condenser lens 33, and a housing 34. Since the concave mirror side sub-display 30 has substantially the same configuration as the planar mirror side sub-display 20, the description thereof is omitted.

[0025] The housing 15 houses the planar mirror 12, the concave mirror 13, and the sub-displays 20 and 30 in the required positions inside the housing 15. The housing 15 also houses the control board on which the main display 11 and the control unit 40 are mounted, in the required position. The main display 11, the planar mirror-side sub-display 20, and the concave mirror-side sub-display 30 are arranged inside the housing 15 such that the relationship between the distance K1 (first distance) from the main display 11 to the windshield 3 for the main display light L1, the distance K2 (second distance) from the planar mirror-side sub-display 20 to the windshield 3 for the planar mirror-side sub-display light L2, and the distance K3 (third distance) from the concave mirror-side sub-display 30 to the windshield 3 is K1 > K2 > K3.

[0026] The control unit 40 controls the main display 11 and sub-displays 20 and 30, in particular, based on information acquired from the vehicle ECU 44, which will be described later. The control unit 40 is a microprocessor, microcontroller, graphics controller, integrated circuit, etc., and performs predetermined processing.

[0027] Vehicle 2 has a vehicle ECU (Electronic Control Unit) 44 in addition to the HUD 1. The vehicle ECU 44 and the control unit 40 are connected, for example, via a CAN (Controller Area Network) bus 45. The vehicle ECU 44 acquires vehicle information necessary for the operation of vehicle 2, such as vehicle speed and engine speed, from various sensors installed on vehicle 2, and controls the operation of vehicle 2.

[0028] Next, I will explain the function of HUD1.

[0029] The relationship between the distance K1 from the main display unit 11 to the windshield 3 for the main display light L1, the distance K2 from the plane mirror side sub-display unit 20 to the windshield 3 for the plane mirror side sub-display light L2, and the distance K3 from the concave mirror side sub-display unit 30 to the windshield 3 for the concave mirror side sub-display light L3 is K1 > K2 > K3. The greater the optical path distance of the display light, the further the virtual image is displayed from the windshield 3, i.e., the further away the virtual image is from the windshield 3. Therefore, the main virtual image V1 is displayed furthest away, the concave mirror side sub-virtual image V3 is displayed closest, and the plane mirror side sub-virtual image V2 is displayed between the main virtual image V1 and the concave mirror side sub-virtual image V3.

[0030] First, based on the control of the control unit 40, the main display light L1 is emitted from the main display unit 11. The main display light L1 is reflected by the reflective surface 12a of the plane mirror 12 toward the reflective surface 13a of the concave mirror 13. The main display light L1 is also reflected by the reflective surface 13a toward the windshield 3. The main display light L1 reflected by the windshield 3 is seen by the driver 4 as a main virtual image V1 in the display area D1 located in front of the windshield 3, as shown in Figure 2. The main virtual image V1 is a series of rectangles of different lengths that are elongated horizontally and displayed below the vehicle 5 in front as the actual scene. The design of the main virtual image V1 is formed so that it gradually becomes longer from top to bottom, creating a sense of depth in the front-to-back direction while being represented two-dimensionally. The design of the main virtual image V1 indicates, for example, the distance to the vehicle in front 5, and is displayed in red when the distance to the vehicle in front 5 is close, blue when it is far, etc. Furthermore, the design of the main virtual image V1 is such that the number of displayed lines increases or decreases depending on the distance between the vehicle and the vehicle ahead 5, for example.

[0031] Furthermore, based on the control of the control unit 40, light is emitted from the plane mirror-side sub-display unit 20. This light is emitted as plane mirror-side sub-display light L2, which forms the design of the plane mirror-side sub-virtual image V2 by passing through the transmission area 12d of the transmission surface 12b. The plane mirror-side sub-display light L2 is emitted toward the reflective surface 13a of the concave mirror 13 and is sequentially reflected by the reflective surface 13a and the windshield 3. The plane mirror-side sub-display light L2 reflected by the windshield 3 is visible to the driver 4 as the plane mirror-side sub-virtual image V2 in a display area D2 located in front of the windshield 3 and behind the main virtual image V1 (between the main virtual image V1 and the concave mirror-side sub-virtual image V3: on the driver 4 side). This plane mirror-side sub-virtual image V2 consists of multiple rectangles of different lengths that are elongated in the vertical direction. The design of the Sub-Virtual Image V2 is formed so that it gradually lengthens from the center outwards in the left-right direction, creating a sense of depth in the front-to-back direction while being represented in two dimensions.

[0032] Furthermore, based on the control of the control unit 40, light is emitted from the concave mirror-side sub-display unit 30. This light is emitted as concave mirror-side sub-display light L3, which forms the design of the concave mirror-side sub-virtual image V3 by passing through the transmission area 13d of the transmission surface 13b. The concave mirror-side sub-display light L3 is reflected by the windshield 3. The concave mirror-side sub-display light L3 reflected by the windshield 3 is visible to the driver 4 as the concave mirror-side sub-virtual image V3 in a display area D3 located in front of the windshield 3 and behind the main virtual image V1 and sub-virtual image V2. This display area D3 is located furthest back (closest to the driver 4) compared to display areas D1 and D2. This concave mirror-side sub-virtual image V3, like the planar mirror-side sub-virtual image V2, consists of multiple rectangles of different lengths that are elongated vertically. The design of the Sub-Virtual Image V3 is formed so that it gradually lengthens from the center outwards in the left-right direction, creating a sense of depth in the front-to-back direction while being represented in two dimensions.

[0033] The designs of the sub-images V2 and V3 are displayed, for example, to alert the driver to the presence of other vehicles approaching from behind in an adjacent lane. For example, when another vehicle approaches from behind in the right lane of vehicle 2, the right concave mirror sub-image V3 is displayed, and then, when the other vehicle overtakes vehicle 2, the right planar mirror sub-image V2 is displayed. At this time, the planar mirror sub-image V2 and the concave mirror sub-image V3 may be displayed in different colors. Because the sub-images V2 and V3 are displayed at different distances from the main image V1, they can create a sense of three-dimensional depth even though they are displayed in two-dimensional display areas D1, D2, and D3, respectively.

[0034] The sub-virtual image V2 on the planar mirror side is located closer to the main virtual image V1 than the sub-virtual image V3 on the concave mirror side in the front-to-back direction. To create a sense of depth for the main virtual image V1, for example, as shown in Figure 2, the multiple rectangular designs of the sub-virtual image V2, which is closer to the main virtual image V1, are displayed symmetrically with respect to the left-right center of the display area D1. That is, the display area D2 is formed symmetrically with respect to the left-right center of the display area D1. Also, the multiple rectangular designs of the sub-virtual image V3, which is farther from the main virtual image V1, are displayed symmetrically with respect to the left-right center of the display area D1, but further out in the left-right direction than the designs of the sub-virtual image V2. That is, the display area D3 is formed symmetrically with respect to the left-right center of the display area D1, but further out in the left-right direction than the designs of the sub-virtual image V2. Furthermore, the designs of the sub-virtual images V2 and V3 are formed so that their vertical length continuously increases outward from the left-right center. As a result, the designs of the sub-virtual images V2 and V3 create a sense of depth in the front-to-back direction.

[0035] Such a HUD1 enables easy three-dimensional display. That is, if stereoscopic display is achieved by forming different images for the left and right eyes, for example, it is necessary to generate high-resolution images for each, requiring a high-performance GPU, large-capacity memory, and a high-brightness light source. However, the HUD1 in this embodiment has sub-display units 20 and 30 that emit display light L2 and L3 to form a predetermined design, using a planar mirror 12 and a concave mirror 13 as half-mirrors, so that sub-virtual images V2 and V3 can be displayed superimposed on the main virtual image V1, and three-dimensional display can be easily achieved. In particular, the HUD1 has sub-display units 20 and 30 with different optical path lengths, and by displaying the sub-virtual images V2 and V3 at different distances, an even greater sense of depth can be created.

[0036] Furthermore, HUD1 positions the planar mirror-side sub-virtual image V2, which is close to the main virtual image V1 in the front-to-back direction, towards the left-to-right center of the display area D1, and positions the concave mirror-side sub-virtual image V3 further outward in the left-to-right direction of the display area D1 than the planar mirror-side sub-virtual image V2. This allows HUD1 to create an even greater sense of depth for the main virtual image V1. The same effect can be achieved if the sub-virtual image V2, which is close to the main virtual image V1 in the front-to-back direction, is positioned towards the vertical center of the display area D1, and the sub-virtual image V3 is positioned further outward in the vertical direction of the display area D1 than the sub-virtual image V2.

[0037] Furthermore, by forming black printing layers 12c and 13c on the transmissive surfaces 12b and 13b of the plane mirror 12 and the concave mirror 13, which form sub-display lights L2 and L3 related to the design of the sub-virtual images V2 and V3, the number of parts can be reduced compared to when separate components are provided.

[0038] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents.

[0039] For example, Figure 5 is a conceptual diagram showing the device configuration of HUD101 as a modified example of HUD1.

[0040] The difference between HUD101 and HUD1 is that the sub-display units 20 and 30 are positioned such that the optical paths (field of view) of the sub-display lights L2 and L3 (or at least a portion thereof) are located outside the optical path P of the main display light L1. For example, if the positioning of the sub-display units 20 and 30 is shifted outward in the left-right direction from the plane mirror 12 or the concave mirror 13, the left-right width of the plane mirror 12 and the concave mirror 13 is expanded outward by the amount of the shift. As a result, the sub-virtual images V2 and V3 are displayed outside the left-right display area D1 of the main virtual image V1 by the amount of the shift from the optical path P. In other words, the display area of ​​HUD1, consisting of display areas D1, D2, and D3, can be expanded simply by increasing the left-right width of the plane mirror 12 and the concave mirror 13 (reflector).

[0041] Although an example was described in which the projection element of HUD1 is the windshield 3, a combiner may be used instead, or together with it.

[0042] The designs of the virtual images V1, V2, and V3 in Figure 2 are examples only and are not limited to them. In other words, as long as a first sub-virtual image and / or a second sub-virtual image with different display positions in the front-to-back direction are displayed with respect to the main virtual image, and a sense of depth is created for the main virtual image V1, the display example in Figure 2 is not the only example.

[0043] The HUD of this disclosure has only one reflector as the first reflector, including a plane mirror 12 and a concave mirror 13, and does not necessarily have to have two reflectors, nor does it have to have three or more reflectors. Furthermore, the HUD of this disclosure only needs to have a sub-display (first sub-display) on the transparent surface side of at least one reflector (first reflector), and does not necessarily have to have sub-displays on all transparent surfaces of multiple reflectors. Also, one reflector may have two sub-displays arranged on it, as in HUD1, or it may have one, three or more sub-displays arranged on it.

[0044] In HUD1, the black printed layers 12c and 13c on the transparent surfaces 12b and 13b form transparent regions 12d and 13d and opaque regions 12e and 13e, thereby forming the designs of the sub-display lights L2 and L3. However, the designs of the sub-display lights may also be formed by forming transparent and opaque regions on the emitter side of the light source of the sub-display. The emitter side of the light source of the sub-display is, for example, a condenser lens 23 or 33, or a separate component for forming the sub-display light design. [Explanation of Symbols]

[0045] 1. 101 Head-Up Display (HUD) 2 vehicles 3. Windshield (projection element) 4. Driver (Observer) 5. The vehicle in front 11 Main display unit 12 plane mirror 12a Reflective surface 12b Transparent surface 12c Black Printing Layer 12d transparent area 12e Opaque area 13 concave mirror 13a Reflective surface 13b Transparent surface 13c Black Printing Layer 13d transparent area 13e Opaque area 15 cabinets 20 Planar mirror side sub-display, sub-display 21, 31 LEDs 22, 32 Circuit boards 23, 33 Condenser Lens 24, 34 cabinets 30 Concave mirror side sub-display, sub-display 40 Control Unit 44 Vehicle ECU 45 CAN bus D1, D2, D3 display area L1 Main Indicator Light L2 Planar mirror side sub-indicator light, sub-indicator light L3 Concave mirror side sub-indicator light, sub-indicator light P optical path V1 Main Illusion V2 Plane mirror side sub-virtual image, sub-virtual image V3 Concave mirror side sub-virtual image, sub-virtual image

Claims

1. A main display unit that emits main display light, A first reflector having a first reflective surface and a first transmissive surface opposite to the first reflective surface, which reflects the main display light toward the projection member at the first reflective surface, thereby causing the main display light reflected by the projection member to be perceived as a main virtual image in front of the projection member by a viewer positioned behind the projection member, A first sub-display unit emits a first sub-display light that passes through the first transmissive surface toward the projection member, thereby causing the first sub-display light reflected by the projection member to be perceived by the viewer as a first sub-virtual image in front of the projection member and behind the main virtual image. A second reflector is positioned between the main display and the first reflector, and has a second reflective surface and a second transmissive surface which is the surface opposite to the second reflective surface, and reflects the main display light at the second reflective surface toward the first reflective surface, The device comprises a second sub-display that emits a second sub-display light through the second transmissive surface toward the first reflective surface, thereby causing the second sub-display light reflected by the first reflective surface and the projection member to be perceived by the viewer as a second sub-virtual image between the main virtual image and the first sub-virtual image, The second sub-display emits the second sub-display light such that the second sub-virtual image is positioned closer to the center of the display area of ​​the main virtual image compared to the first sub-virtual image. A head-up display that displays the first sub-image on the adjacent lane side when another vehicle approaches from behind in the adjacent lane, and then displays the second sub-image on the adjacent lane side when the other vehicle overtakes the vehicle.

2. The head-up display according to claim 1, wherein the main virtual image is displayed below the vehicle in front as a real scene, and consists of multiple shapes of different lengths that extend in the left-right direction, gradually becoming longer from top to bottom.

3. The head-up display according to claim 1, wherein the first sub-display or the second sub-display is arranged such that at least a portion of the optical path of the first sub-display light or the second sub-display light is located outside the optical path of the main display light.

4. The first transparent surface has a transparent region and an opaque region, The head-up display according to claim 1, wherein the first sub-display unit forms the first sub-display light relating to the design of the first sub-virtual image by light transmitted through the transparent region.

5. The second transparent surface has a transparent region and an opaque region, The head-up display according to claim 1, wherein the second sub-display unit forms the second sub-display light relating to the design of the second sub-virtual image by light transmitted through the transparent region.

Images