Head-up display

• US 10,642,032 B2
• Filed: 07/03/2018
• Issued: 05/05/2020
• Est. Priority Date: 01/20/2016
• 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: Kasazumi, Ken'ichi, Mori, Toshiya, Okayama, Hiroaki, Kuzuhara, Satoshi, Asai, Yosuke
• Primary Examiner(s): Tzeng, Fred
• Application Number:
  US16/026,109
• Publication Number:
  US 20180314064A1
• Time in Patent Office: 672 Days
• Field of Search: 345 7
• CPC Class Codes: B60K 2360/23 using reflectors
• CPC Class Codes: B60K 2360/334 Projection means
• CPC Class Codes: B60K 35/00 Instruments specially adapted for vehicles; Arrangement of instruments in or on vehicles
• CPC Class Codes: B60K 35/23 Head-up displays [HUD] optical aspects of head-up displays G02B27/01
• CPC Class Codes: B60Y 2400/92 Driver displays
• CPC Class Codes: G02B 2027/011 comprising device for correcting geometrical aberrations, distortion
• CPC Class Codes: G02B 2027/0118 comprising devices for improving the contrast of the display / brillance control visibility
• CPC Class Codes: G02B 2027/0127 comprising devices increasing the depth of field
• CPC Class Codes: G02B 2027/0136 with a single image source for both eyes
• CPC Class Codes: G02B 2027/0185 Displaying image at variable distance
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 3/08 with discontinuous faces, e.g. Fresnel lens diffractive Fresnel lenses G02B5/1876
• CPC Class Codes: G02B 30/54 the 3D volume being generated by moving a 2D surface, e.g. by vibrating or rotating the 2D surface
• CPC Class Codes: G02B 5/003 Light absorbing elements

Abstract

A head-up display includes an optical system that radiates light forming a projected image toward an eye box. The eye box is a predetermined range in which eyes of an observer are assumed to be present. The optical system includes a Fresnel lens having a bumpy surface having a sawtooth-shaped cross-section. The bumpy surface is formed concentrically around an optical axis, and formed by alternately disposing first surfaces as light condensing surfaces that allow incident light to converge toward a focal point, and second surfaces as wall surfaces that do not allow the incident light to converge toward the focal point. The second surfaces are inclined with respect to the optical axis of the Fresnel lens at an angle to reflect the incident light striking the wall surfaces, in a direction toward outside of a range of the eye box.

Claims

1. A head-up display comprising an optical system that radiates light forming a projected image toward an eye box, the eye box being a predetermined range in which eyes of an observer are assumed to be present,

wherein the optical system includes a Fresnel lens having a bumpy surface having a sawtooth-shaped cross-section, the bumpy surface being formed concentrically around an optical axis, and formed by alternately disposing light condensing surfaces that allow incident light to converge toward a focal point, and wall surfaces that do not allow the incident light to converge toward the focal point, and

each of the wall surfaces is inclined with respect to the optical axis of the Fresnel lens at an angle to reflect the incident light striking each of the wall surfaces, in a direction toward outside of a range of the eye box.

2. The head-up display according to claim 1, wherein the wall surfaces includes a first wall surface and a second wall surface disposed more outside than the first wall surface, an inclination of the second wall surface with respect to the optical axis is larger than an inclination of the first wall surface with respect to the optical axis.

3. The head-up display according to claim 1, further comprising:

a light source that emits light;

a scanner that performs scanning with the light from the light source; and

a screen through which light from the scanner passes to form an image on the screen,

wherein the optical system displays, in space, a virtual image of the image formed on the screen.

4. A head-up display comprising an optical system that radiates light forming a projected image toward an eye box, the eye box being a predetermined range in which eyes of an observer are assumed to be present,

wherein the optical system includes a Fresnel lens having a bumpy surface having a sawtooth-shaped cross-section, the bumpy surface being formed concentrically around an optical axis, and formed by alternately disposing light condensing surfaces that allow incident light to converge to a focal point, and wall surfaces that do not allow the incident light to converge toward the focal point, and

each of the wall surfaces is inclined with respect to the optical axis of the Fresnel lens at an angle such that the incident light on the Fresnel lens does not directly strike each of the wall surfaces.

5. The head-up display according to claim 4, wherein the light condensing surfaces and the wall surfaces are respectively disposed to be overlapped with each other in a direction of the optical axis.