Image display device

• US 9,989,778 B2
• Filed: 11/07/2016
• Issued: 06/05/2018
• Est. Priority Date: 11/25/2015
• Status: Active Grant

• Current Assignee: Panasonic Automotive Systems Company of America (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: Furuya, Hiroyuki
• Primary Examiner(s): HOWARD, RYAN D
• Application Number:
  US15/345,415
• Publication Number:
  US 20170146809A1
• Time in Patent Office: 575 Days
• Field of Search: 359 13, 359630-633
• CPC Class Codes: B60K 2360/333 Lasers
• CPC Class Codes: B60K 2360/334 Projection means
• CPC Class Codes: B60K 2360/347 Optical elements for superposition of display information
• CPC Class Codes: B60K 35/00 Instruments specially adapted for vehicles; Arrangement of instruments in or on vehicles
• CPC Class Codes: G02B 2027/011 comprising device for correcting geometrical aberrations, distortion
• CPC Class Codes: G02B 26/105 with one or more pivoting mirrors or galvano-mirrors G02B26/101 takes precedence
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 27/48 Laser speckle optics
• CPC Class Codes: G03B 21/2033 LED or laser light sources
• CPC Class Codes: G03B 21/2046 Positional adjustment of light sources
• CPC Class Codes: G03B 21/28 Reflectors in projection beam in illumination beam G03B21/2066
• CPC Class Codes: G03B 21/625 Lenticular translucent screens
• CPC Class Codes: H04N 9/3129 scanning a light beam on the display screen scanning a light beam on a screen in displays other than projection devices G09G3/02; scanning systems in general G02B26/10; projectors using laser light sources in general H04N9/3161
• CPC Class Codes: H04N 9/3155 for controlling the light source light source control per se H05B35/00 – H05B47/00; control of an illumination source for displays in general G09G3/3406
• CPC Class Codes: H04N 9/3161 using laser light sources using laser beams scanning the display screen H04N9/3129
• CPC Class Codes: H04N 9/3164 using multiple light sources

Abstract

An image display device includes a light source, a scanner, a screen, a virtual image optical system and a screen incident angle correcting optical system. The light source emits laser light. The scanner scans the laser light. An image is formed on the screen by the scanned laser light. The virtual image optical system generates a virtual image of the image by the laser light having transmitted through the screen. The screen incident angle correcting optical system orients the scanned laser light toward the screen. The scanner performs at least first scanning and second scanning that has a scanning direction different from a scanning direction of the first scanning. The screen includes a lenticular lens having a lens pitch in a direction parallel to the first scanning. The lens pitch of the lenticular lens is larger than a beam diameter of the laser light near a light receiving surface of the screen.

Claims

1. An image display device comprising:

a light source which emits laser light;

a scanner which scans the laser light emitted from the light source;

a screen on which an image is formed by the laser light scanned with the scanner;

a virtual image optical system which generates a virtual image of the image by the laser light having transmitted through the screen; and

a screen incident angle correcting optical system which orients the laser light scanned with the scanner toward the screen, wherein;

the scanner performs at least first scanning and second scanning that has a scanning direction different from a scanning direction of the first scanning, and makes a scanning speed of the first scanning higher than a scanning speed of the second scanning,

the virtual image optical system generates the virtual image larger than the image formed on the screen,

the screen incident angle correcting optical system makes the laser light perpendicularly incident to a light receiving surface of the screen,

the screen includes a lenticular lens having a lens pitch in a direction parallel to the scanning direction of the first scanning and a louver structure having an inter-louver pitch in a direction parallel to the scanning direction of the second scanning,

the lens pitch of the lenticular lens is larger than a beam diameter of the laser light near the light receiving surface of the screen, and

the inter-louver pitch of the louver structure is smaller than the lens pitch of the lenticular lens.

2. The image display device according to claim 1, wherein the screen incident angle correcting optical system is a telecentric f-θ

lens.

3. The image display device according to claim 1, wherein the screen causes the lenticular lens to function as a light receiving surface, and causes a wedge surface of the louver structure to function as an emission surface.

4. The image display device according to claim 1, wherein the louver structure includes a reflecting function of reflecting the laser light and an absorbing function of absorbing the laser light, and switches the reflecting function and the absorbing function according to an incident angle of the laser light.

5. The image display device according to claim 1, wherein a transverse mode in the light source is a single mode.

6. The image display device according to claim 1, wherein at least one of a red light source, a green light source and a blue light source constituting the light source lights up only once while one pixel is illuminated.

7. The image display device according to claim 1, wherein a diameter of a mirror constituting the scanner is from 0.8 mm to 1.5 mm both inclusive.

8. An image display device comprising:

a light source which emits laser light;

a scanner which scans the laser light emitted from the light source;

a screen on which an image is formed by the laser light scanned with the scanner;

a virtual image optical system which generates a virtual image of the image by the laser light having transmitted through the screen; and

a screen incident angle correcting optical system which orients the laser light scanned with the scanner toward the screen, wherein;

the scanner performs at least first scanning and second scanning that has a scanning direction different from a scanning direction of the first scanning, and makes a scanning speed of the first scanning higher than a scanning speed of the second scanning,

the virtual image optical system generates the virtual image larger than the image formed on the screen,

the screen incident angle correcting optical system makes the laser light perpendicularly incident to a light receiving surface of the screen,

the screen includes a first lenticular lens including a first lens pitch in a direction parallel to the scanning direction of the first scanning and a second lenticular lens including a second lens pitch in a direction parallel to the scanning direction of the second scanning,

the first lenticular lens and the second lenticular lens are arranged along an optical axis on which the laser light is incident, and

the second lens pitch of the second lenticular lens is smaller than the first lens pitch of the first lenticular lens.

9. The image display device according to claim 8, wherein the first lenticular lens and the second lenticular lens are disposed at a top surface of the screen and at a back surface of the screen, respectively.

10. The image display device according to claim 8, wherein the first lens pitch of the first lenticular lens satisfies the following equation,

11. The image display device according to claim 8, wherein the scanning direction of the first scanning is orthogonal to the scanning direction of the second scanning.