Display, display system, image projection system, and movable object
Provided is a head-up display including a liquid-crystal panel including a display screen, a Fresnel lens which is on an opposite side of the liquid-crystal panel from the display screen, a light-diffusion member between the liquid-crystal panel and the Fresnel lens, a backlight emitting light toward the Fresnel lens, a heat sink accommodating the light-diffusion member, the backlight and the Fresnel lens, and a mirror that forms a virtual image corresponding to an image displayed on the display screen of the liquid-crystal panel, in a target space, where a surface of the Fresnel lens facing the backlight is uneven.
1. A head-up display comprising:
a liquid-crystal panel including a display screen;
a Fresnel lens which is on an opposite side of the liquid-crystal panel from the display screen;
a light-diffusion member between the liquid-crystal panel and the Fresnel lens;
a backlight emitting light toward the Fresnel lens;
a heat sink accommodating the light-diffusion member, the backlight and the Fresnel lens; and
a mirror that forms a virtual image corresponding to an image displayed on the display screen of the liquid-crystal panel, in a target space,
wherein
a surface of the Fresnel lens facing the backlight is uneven.
2. The head-up display according to claim 1 , wherein
the light-diffusion member has a transmittance equal to or larger than 70%.
3. The head-up display according to claim 1 , wherein
the Fresnel lens is directly contacted to the heat sink.
4. The head-up display according to claim 1 , wherein
the heat sink has a plurality of plate-shaped fins protruding from an outer surface of the heat sink in a direction intersecting a direction in which the light-diffusion member and the Fresnel lens are arranged.
5. The head-up display according to claim 1 , wherein
the light-diffusion member is thinner than the Fresnel lens.
6. The head-up display according to claim 1 , wherein
the light-diffusion member has a thickness equal to or smaller than 300 μm.
7. The head-up display according to claim 1 , wherein
the light-diffusion member includes a plurality of fine particles; and
an average particle size of the plurality of fine particles is equal to or smaller than 20 μm.
8. The head-up display according to claim 1 , wherein
light emitted from the backlight diverges in a direction toward the Fresnel lens.
9. The head-up display according to claim 1 , wherein
light emitted from the backlight converges in a direction toward the Fresnel lens.
10. The head-up display according to claim 1 , wherein
the light-diffusion member includes the light-diffusion structure; and
the light-diffusion structure is provided to a surface of the light-diffusion member facing the liquid-crystal panel.
11. The head-up display according to claim 1 , wherein
the light-diffusion member includes the light-diffusion structure; and
the light-diffusion structure is provided to a surface of the light-diffusion member facing the Fresnel lens.
12. The head-up display according to claim 1 , wherein
the light-diffusion member includes the light-diffusion structure; and
the light-diffusion structure is provided to each of a surface of the light-diffusion member facing the liquid-crystal panel and a surface of the light-diffusion member facing the Fresnel lens.
13. The head-up display according to claim 1 , wherein
the light-diffusion member is made of glass or resin.
14. The head-up display according to claim 1 , wherein
the heat sink is made of aluminum.
15. The head-up display according to claim 1 , wherein
the heat sink includes a body part having a hollow rectangular prism shape.
16. The head-up display according to claim 1 , wherein
the backlight includes light emitting diodes or laser diodes.
17. The head-up display according to claim 1 , wherein
the Fresnel lens is made of glass or resin.
18. The head-up display according to claim 1 , wherein
the light-diffusion member is made of resin in which fine particles are dispersed.
19. An image projection system comprising:
a liquid-crystal panel including a display screen;
a Fresnel lens which is on an opposite side of the liquid-crystal panel from the display screen;
a light-diffusion structure between the liquid-crystal panel and the Fresnel lens;
a backlight emitting light toward the Fresnel lens; and
a main part accommodating the light-diffusion structure and the Fresnel lens, wherein
a surface of the Fresnel lens facing the backlight is uneven.
20. A head-up display, comprising:
the image projection system according to claim 19 ; and
a mirror that forms a virtual image corresponding to an image displayed on the display screen of the liquid-crystal panel, in a target space.