HEAD-UP DISPLAY DEVICE

Abstract

The present invention relates to a head-up display device that allows a viewer to view an actual scene overlapped with a virtual image, and that is capable of creating a display image with suppressed luminance variation. A MEMS scanner scans synthesized laser light two-dimensionally in the main scanning direction H and the sub-scanning direction V substantially orthogonal to the main scanning direction H. A controller unit causes a first scan for generating a display image M on a transmissive screen by scanning in the main scanning direction H at high speed while scanning in the sub-scanning direction V, and a second scan for scanning a position displaced more toward the sub-scanning direction V than the first scan on the transmissive screen.

Claims

1. A head-up display device, comprising: a light source configured to emit laser light; a scanning unit configured to two-dimensionally scan the laser light in a main scanning direction and a sub-scanning direction different from the main scanning direction; a lens array screen having a plurality of micro lenses that are periodically arranged, the lens array screen being configured to diffuse the laser light scanned by the scanning unit and direct the laser light to a visual recognition region; and a control unit configured to control the light source and the scanning unit to generate a display image on the lens array screen, wherein the control unit causes first scanning to be performed and causes second scanning to be performed, the first scanning being scanning in which scanning is performed in the sub-scanning direction while scanning is being performed in the main scanning direction at a high speed, the second scanning being scanning in which a position shifted in the sub-scanning direction from the first scanning on the lens array screen is scanned.

2. The head-up display device according to claim 1, wherein the same display image is generated in the first scanning and the second scanning.

3. The head-up display device according to claim 1, wherein a pitch of the micro lenses in the sub-scanning direction is larger than a diameter of the laser light in the sub-scanning direction.

4. The head-up display device according to claim 1, wherein the control unit performs the first scanning and the second scanning within temporal resolution of a human eye.

5. The head-up display device according to claim 1, wherein the micro lenses are rectangular lenses two-dimensionally arranged in the main scanning direction and the sub-scanning direction; and the control unit moves a scanning position in the sub-scanning direction by the same distance as a pitch of the micro lenses while the scanning unit is scanning a single line in the main scanning direction.

6. The head-up display device according to claim 1, wherein a shift between the first scanning and the second scanning in the sub-scanning direction is smaller than a pitch of the micro lenses in the sub-scanning direction.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0077] FIG. 1 is a conceptual diagram showing a mode in which a HUD device according to an embodiment of the invention is mounted on a vehicle.

[0078] FIG. 2 is a schematic configuration diagram of the HUD device according to the above embodiment.

[0079] FIG. 3 is a schematic configuration diagram showing a synthesized laser light generation device in the above embodiment.

[0080] FIG. 4 shows a scanning mode on a transmissive screen in the above embodiment.

[0081] FIG. 5(a) is an enlarged plan view of an MLA. FIG. 5(b) is an enlarged plan view of an aperture array.

[0082] FIG. 6 is a schematic cross-sectional view of the transmissive screen in FIG. 4 in a side view.

[0083] FIG. 7 is a block diagram for explaining a control system of the HUD device according to the above embodiment.

[0084] FIG. 8 is a conceptual diagram showing a relationship between a beam diameter on the transmissive screen and a pitch of the MLA in the above embodiment.

[0085] FIG. 9 shows a distributed light intensity distribution in a main scanning direction in an eye box by using the HUD device of the above embodiment.

[0086] FIG. 10 shows scanning in the main scanning direction in the above embodiment and distributed light intensity distributions in the main scanning direction in the eye box, the distributed light intensity distributions being generated by this scanning in the main scanning direction.

[0087] FIG. 11 shows an hourly averaged distributed light intensity distribution in the main scanning direction in the eye box in the above embodiment.

[0088] FIG. 12 shows scanning in a sub-scanning direction in the above embodiment and distributed light intensity distributions in the sub-scanning direction in the eye box, the distributed light intensity distributions being generated by this scanning in the sub-scanning direction.

[0089] FIG. 13 shows time transition of a sub-scanning position in the HUD device of the above embodiment.

[0090] FIG. 14 is a diagram for explaining a mode of a scanning line scanned in each sub-frame in the above embodiment.

[0091] FIG. 15 shows an hourly averaged distributed light intensity distribution in the sub-scanning direction in the eye box in the above embodiment.

INDUSTRIAL APPLICABILITY

[0092] The invention relates to a head-up display device for superimposing a virtual image on a real view to cause the virtual image to be visually recognized. The head-up display device is placed in, for example, a dashboard of a vehicle and is suitable as a display device for emitting image light toward a windshield of a vehicle.

REFERENCE SIGNS LIST

[0093] 1 HUD device (head-up display device) [0094] 2 vehicle [0095] 3 windshield [0096] 4 eye box [0097] 10 synthesized laser light generation device [0098] 11 LD (11r, 11g, 11b) [0099] 12 condensing optical system (12r, 12g, 12b) [0100] 13 optical axis adjustment unit (13r, 13g) [0101] 20 MEMS scanner [0102] 30 field lens [0103] 40 transmissive screen (lens array screen) [0104] 41 MLA (micro lens array) [0105] 41a micro lens [0106] 42 aperture array [0107] 42a opening portion [0108] 42b light shielding portion [0109] 50 relay optical unit [0110] 51 plane mirror [0111] 52 magnifying mirror [0112] 100 LD control unit (control unit) [0113] 200 MEMS control unit (control unit) [0114] 300 controller unit (control unit) [0115] 310 input processing unit [0116] 320 memory control unit [0117] 330 frame buffer [0118] 340 display control unit [0119] 500 synthesized laser light [0120] 600 image light [0121] 710 light intensity distribution in main scanning direction [0122] 720 light intensity distribution in sub-scanning direction [0123] 810 distributed light intensity distribution in main scanning direction [0124] 820 distributed light intensity distribution in sub-scanning direction [0125] R red laser light [0126] G green laser light [0127] B blue laser light [0128] M display image [0129] W virtual image