Head-up display system and image display method based on head-up display system

1 . A head-up display (HUD) system, wherein the HUD system comprises a windshield, a picture generation unit (PGU), and an optical element, wherein the windshield comprises a first windshield surface and a second windshield surface;

the PGU is configured to generate a picture, and project a light beam corresponding to the picture to the optical element;

the optical element is configured to image the picture and direct the light beam to a target position on the first windshield surface;

the first windshield surface is configured to refract the light beam to the second windshield surface, and reflect the light beam to a human eye for receiving, wherein after reflection by the first windshield surface, the light beam forms a first virtual image with the picture;

the second windshield surface is configured to reflect a light beam refracted from the first windshield surface to the first windshield surface;

the first windshield surface is further configured to refract a light beam reflected from the second windshield surface to the human eye for receiving, wherein after reflection by the second windshield surface and refraction by the first windshield surface, the light beam forms a second virtual image with the picture; and

at least one processor configured to calculate an included angle between a first direction and a second direction based on a thickness of the windshield, a refractive index of the windshield, a coangle of an incident angle of the light beam directed by the optical element to the first windshield surface, and a distance between the first virtual image and the human eye, wherein the first direction is a direction from the first virtual image to the human eye, and the second direction is a direction from the second virtual image to the human eye.

2 . The HUD system according to claim 1 , wherein the HUD system further comprises at least one of a first driving apparatus and a second driving apparatus;

the first driving apparatus is configured to adjust a position of the PGU to make the PGU close to or away from the optical element, and

the second driving apparatus is configured to adjust a position of the optical element to make the optical element close to or away from the PGU.

3 . The HUD system according to claim 2 , wherein the first driving apparatus is further configured to drive the PGU to rotate, to adjust a size of the coangle; and

the second driving apparatus is further configured to drive the optical element to rotate, to adjust the size of the coangle.

4 . The HUD system according to claim 1 , wherein the distance between the first virtual image and the human eye is equal to a sum of a first distance and a second distance, the first distance is a distance between the first virtual image and the target position on the first windshield surface, the second distance is a distance between the target position on the first windshield surface and the human eye, and the first distance is determined by a focal length of the optical element and a distance between the PGU and the optical element.

5 . The HUD system according to claim 1 , wherein the included angle is calculated by substituting the thickness of the windshield, the refractive index of the windshield, the coangle, and the distance between the first virtual image and the human eye into a formula; and

the formula is

φ

=

arc

⁢

sin

[

2

⁢

h

D

×

sin

⁢

(

θ

1

)

n

2

cos

⁢

(

θ

1

)

2

-

1

]

,

wherein

φ indicates the included angle, h indicates the thickness of the windshield, n indicates the refractive index of the windshield, D indicates the distance between the first virtual image and the human eye, and θ1 indicates the coangle.

6 . The HUD system according to claim 1 , wherein there is an interlayer between the first windshield surface and the second windshield surface, and the interlayer is configured to fasten the first windshield surface and the second windshield surface together; and the optical element is a curved surface reflector, a lens, a liquid crystal on silicon (LCOS), or a diffractive optical element (DOE).

7 . A head-up display (HUD) system, wherein the HUD system comprises a windshield, a picture generation unit (PGU), and an optical element, wherein the windshield comprises a first windshield surface and a second windshield surface;

the PGU is configured to generate a picture, and project a light beam corresponding to the picture to the optical element;

the optical element is configured to image the picture and direct the light beam to a target position on the first windshield surface;

the first windshield surface is configured to refract the light beam to the second windshield surface, and reflect the light beam to a human eye for receiving, wherein after reflection by the first windshield surface, the light beam forms a first virtual image with the picture;

the second windshield surface is configured to reflect a light beam refracted from the first windshield surface to the first windshield surface;

the first windshield surface is further configured to refract a light beam reflected from the second windshield surface to the human eye for receiving, wherein after reflection by the second windshield surface and refraction by the first windshield surface, the light beam forms a second virtual image with the picture; and

at least one processor configured to calculate an included angle between a first direction and a second direction based on a thickness of the windshield, a refractive index of the windshield, a coangle of an incident angle of the light beam directed by the optical element to the first windshield surface, and a distance between the first virtual image and the target position on the first windshield surface, and wherein the first direction is a direction from the first virtual image to the human eye, and the second direction is a direction from the second virtual image to the human eye.

8 . The HUD system according to claim 7 , wherein the HUD system further comprises at least one of a first driving apparatus and a second driving apparatus;

the first driving apparatus is configured to adjust a position of the PGU to make the PGU close to or away from the optical element; and

the second driving apparatus is configured to adjust a position of the optical element to make the optical element close to or away from the PGU.

9 . The HUD system according to claim 8 , wherein the first driving apparatus is further configured to drive the PGU to rotate, to adjust a size of the coangle; and

the second driving apparatus is further configured to drive the optical element to rotate, to adjust the size of the coangle.

10 . An image display method applied to an HUD system, wherein the HUD system comprises a windshield, a PGU, and an optical element, wherein the windshield comprises a first windshield surface and a second windshield surface; and the method comprises:

generating, by the PGU, a picture, and projecting a light beam corresponding to the picture to the optical element;

imaging, by the optical element, the picture, and directing the light beam to a target position on the first windshield surface;

refracting, by the first windshield surface, the light beam to the second windshield surface, and reflecting the light beam to a human eye for receiving, wherein after reflection by the first windshield surface, the light beam forms a first virtual image with the picture;

reflecting, by the second windshield surface, a light beam refracted from the first windshield surface to the first windshield surface;

refracting, by the first windshield surface, a light beam reflected from the second windshield surface to the human eye for receiving, wherein after reflection by the second windshield surface and refraction by the first windshield surface, the light beam forms a second virtual image with the picture;

calculating an included angle between a first direction and a second direction based on a thickness of the windshield, a refractive index of the windshield, a coangle of an incident angle of the light beam directed by the optical element to the first windshield surface, and a distance between the first virtual image and the human eye, wherein the first direction is a direction from the first virtual image to the human eye, and the second direction is a direction from the second virtual image to the human eye; and

adjusting at least one of the thickness of the windshield, the refractive index of the windshield, the coangle of an incident angle of the light beam directed by the optical element to the first windshield surface, or the distance between the first virtual image and the human eye to adjust the included angle between the first direction and the second direction to be less than a preset angle.

11 . The method according to claim 10 , wherein the HUD system further comprises at least one of a first driving apparatus and a second driving apparatus; and the method further comprises:

adjusting, by the first driving apparatus, a position of the PGU to make the PGU close to or away from the optical element; and

adjusting, by the second driving apparatus, a position of the optical element to make the optical element close to or away from the PGU.

12 . The method according to claim 11 , wherein the method further comprises:

driving, by the first driving apparatus, the PGU to rotate, to adjust a size of the coangle; and

driving, by the second driving apparatus, the optical element to rotate, to adjust the size of the coangle.

13 . The method according to claim 10 , wherein the distance between the first virtual image and the human eye is equal to a sum of a first distance and a second distance, the first distance is a distance between the first virtual image and the target position on the first windshield surface, and the second distance is a distance between the target position on the first windshield surface and the human eye; and the method further comprises:

changing the first distance by adjusting a focal length of the optical element and a distance between the PGU and the optical element.

14 . The method according to claim 10 , wherein the included angle is calculated by substituting the thickness of the windshield, the refractive index of the windshield, the coangle, and the distance between the first virtual image and the human eye into a formula; and

the formula is

φ

=

arc

⁢

sin

[

2

⁢

h

D

×

sin

⁢

(

θ

1

)

n

2

cos

⁢

(

θ

1

)

2

-

1

]

,

wherein

φ indicates the included angle, h indicates the thickness of the windshield, n indicates the refractive index of the windshield, D indicates the distance between the first virtual image and the human eye, and θ1 indicates the coangle.

15 . The method according to claim 10 , wherein there is an interlayer between the first windshield surface and the second windshield surface, and the interlayer is configured to fasten the first windshield surface and the second windshield surface together; and the optical element is a curved surface reflector, a lens, a liquid crystal on silicon (LCOS), or a diffractive optical element (DOE).

16 . A display apparatus, wherein the display apparatus comprises a picture generation unit (PGU) and an optical element, wherein

the PGU is configured to generate a picture, and project a light beam corresponding to the picture to the optical element; and

the optical element is configured to image the picture and direct the light beam to a target position on a first windshield surface of a windshield, wherein the first windshield surface is configured to refract the light beam to a second windshield surface of the windshield, and reflect the light beam to a human eye for receiving, wherein after reflection by the first windshield surface, the light beam forms a first virtual image with the picture; the second windshield surface is configured to reflect a light beam refracted from the first windshield surface to the first windshield surface; the first windshield surface is further configured to refract a light beam reflected from the second windshield surface to the human eye for receiving, wherein after reflection by the second windshield surface and refraction by the first windshield surface, the light beam forms a second virtual image with the picture; and

at least one processor configured to calculate an included angle between a first direction and a second direction based on a thickness of the windshield, a refractive index of the windshield, a coangle of an incident angle of the light beam directed by the optical element to the first windshield surface, and a distance between the first virtual image and the human eye, wherein the first direction is a direction from the first virtual image to the human eye, and the second direction is a direction from the second virtual image to the human eye.

17 . The display apparatus according to claim 16 , further comprising at least one of a first driving apparatus and a second driving apparatus, wherein

the first driving apparatus is configured to adjust a position of the PGU to make the PGU close to or away from the optical element; and

the second driving apparatus is configured to adjust a position of the optical element to make the optical element close to or away from the PGU.

18 . The display apparatus according to claim 17 , wherein the first driving apparatus is further configured to drive the PGU to rotate, to adjust a size of the coangle; and

the second driving apparatus is further configured to drive the optical element to rotate, to adjust the size of the coangle.

19 . The display apparatus according to claim 16 , wherein the included angle is calculated by substituting the thickness of the windshield, the refractive index of the windshield, the coangle, and the distance between the first virtual image and the human eye into a formula; and

the formula is

φ

=

arc

⁢

sin

[

2

⁢

h

D

×

sin

⁢

(

θ

1

)

n

2

cos

⁢

(

θ

1

)

2

-

1

]

,

wherein

φ indicates the included angle, h indicates the thickness of the windshield, n indicates the refractive index of the windshield, D indicates the distance between the first virtual image and the human eye, and θ1 indicates the coangle.

20 . The display apparatus according to claim 16 , wherein the optical element is a curved surface reflector, a lens, a liquid crystal on silicon (LCOS), or a diffractive optical element (DOE).