Head-up display
A combiner, a head-up display module, and to a vehicle with a head-up display module. To improve the image quality of a head-up display, a combiner is provided that has a transparent sheet. The transparent sheet is configured to reflect a projected image toward a user. The transparent sheet has a thickness less than 1 mm.
1. A combiner for a head-up display module for a vehicle, comprising:
a transparent sheet having two parallel sides with a thickness of less than 1 mm, and configured to reflect a projected image toward a user,
wherein each side projects a respective image and a distance between the respective images is below a discernable threshold.
2. The combiner according to claim 1 , wherein the thickness is constant across the transparent sheet.
3. The combiner according to claim 1 , further comprising:
a support structure;
wherein the transparent sheet is mounted on the support structure such that the support structure provides mechanical support for the transparent sheet.
4. The combiner according to claim 3 , wherein the support structure comprises:
a first pin; and
a second pin;
wherein the first and second pins are disposed on opposing sides of the transparent sheet.
5. The combiner according to claim 3 , wherein the support structure is a frame surrounding the transparent sheet.
6. The combiner according to claim 5 , wherein the frame and the transparent sheet are formed of a same material and in a single piece.
7. The combiner according to claim 3 , wherein the support structure is a part of a vehicle dashboard module.
8. The combiner according to claim 1 ,
wherein the first and second surfaces are configured to have different reflectivity.
9. The combiner according to claim 1 , wherein the thickness is less than 500 μm.
10. The combiner according to claim 1 , wherein the thickness is less than 250 μm.
11. The combiner according to claim 1 , wherein the combiner thickness t is upper-bounded by:
t
<
D
·
π
180
·
Q
·
n
1
n
0
·
1
-
(
n
0
n
1
)
2
·
sin
2
(
α
)
sin
(
2
·
α
)
where:
t is the combiner thickness,
Q is a quality factor
D is a distance between a user and a projected double image;
n 1 is a refractive index of the combiner;
n 0 is a refractive index of air;
α is an incidence angle of light beams coming from the image towards the combiner.
12. A head-up display module for a vehicle, comprising:
an image projector; and
a combiner comprising a transparent sheet having two parallel sides with a thickness of less than 1 mm, and configured to reflect a projected image toward a user, wherein each side projects a respective image and a distance between the respective images is below a discernable threshold;
wherein the image projector is configured to project the projected image toward the combiner.
13. A vehicle, comprising:
a head-up display module, comprising:
an image projector; and
a combiner comprising a transparent sheet having two parallel sides with a thickness of less than 1 mm, and configured to reflect a projected image toward a user,
wherein each side projects a respective image and a distance between the respective images is below a discernable threshold; and
wherein the image projector is configured to project the projected image toward the combiner.
14. A cockpit display for an airplane, comprising a head-up display module, comprising:
an image projector; and
a combiner comprising a transparent sheet having a thickness of less than 1 mm, and configured to reflect a projected image toward a user on each of its two parallel sides;
wherein the image projector is configured to project the projected image toward the combiner.
15. The cockpit display for an airplane according to claim 14 , wherein each side of the combiner projects a respective image and a distance between the respective images is below a discernable threshold.