Head up display unit, liquid crystal display panel, and method of fabricating the liquid crystal display panel

• US 5,892,598 A
• Filed: 05/29/1996
• Issued: 04/06/1999
• Est. Priority Date: 07/15/1994
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Taketomi, Yoshinao, Tsutsui, Hiroshi, Asakawa, Shiro, Okuda, Eiichiro
• Primary Examiner(s): Spyrou, Cassandra
• Assistant Examiner(s): Schuberg, Darren E.
• Application Number:
  US08/617,879
• Time in Patent Office: 1,042 Days
• Field of Search: 359/13, 359/14, 359/34, 345/7, 349/11, 349/86
• US Class Current: 359/13
• CPC Class Codes: G02B 2027/0125 Field-of-view increase by wavefront division
• CPC Class Codes: G02B 2027/0154 with movable elements
• CPC Class Codes: G02B 2027/0156 with optionally usable elements
• CPC Class Codes: G02B 27/01 Head-up displays
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 5/30 Polarising elements light-modulating devices with active elements G02F1/00

Abstract

A head up display unit equipped at least with transparent and flat image information display means, transparent and flat light irradiating means arranged in an opposed and close contact relationship with the image information display means, light supply means for supplying light to the light irradiating means, image-display control means for controlling image display, and light-supply control means for controlling light supply. The display unit is a compact head up display unit which can be used in any place in the interior of an automobile.

Claims

1. A head up display unit comprising:

transparent and flat image information display means having a front surface;

transparent and flat light irradiating means, said light irradiating means between said image information display means and a user;

light supply means for supplying light to a surface of said light irradiating means, said light irradiating means reflecting said light from said front surface of said image information display means;

image-display control means for controlling an image display of said image information display means; and

light-supply control means for controlling the light supply of said light supply means.

2. The head up display unit as set forth in claim 1, wherein said transparent and flat image information display means is one selected from a group of a liquid crystal panel, a polymer dispersed liquid crystal panel, and a ferroelectric thin film.

3. The head up display unit as set forth in claim 1, wherein said light irradiating means has optical-path converting means for emitting incident light which was incident from said light supply means arranged on part or all of the peripheral end face of said light irradiating means, in a surface direction of said light irradiating means.

4. The head up display unit as set forth in claim 3, wherein said optical-path converting means is one selected from a group of a volume phase hologram, a phase diffraction grating comprising asymmetrical unevenness, and a half mirror.

5. The head up display unit as set forth in claim 4, wherein said optical-path converting means is a volume phase hologram having a plurality of sections, and at least a first section of the said plurality of sections is different than a second section of said plurality of sections.

6. The head up display unit as set forth in claim 1, wherein said light supply means is a light source itself emitting light, such as various kinds of lamps, a discharge tube, electroluminescence, a plasma illuminant, a light emitting diode, and a laser, or is a phosphor and a light source which excites said phosphor.

7. The head up display unit as set forth in claim 1, wherein said light supply means is provided with a light source and an optical fiber for guiding light from said light source.

8. A head up display unit, wherein the head up display device as set forth in claim 1 is placed on a dashboard of an automobile, has a drive portion which can be pulled down before and after, and is fixed at an arbitrary angle.

9. A head up display unit, wherein the head up display device as set forth in claim 1 is fixed by freely rotatable fixing tool attached to the upper portion of a windshield of an automobile and is pulled down to the windshield surface when it is used.

10. A head up display unit, wherein the head up display device as set forth in claim 1 is placed in the vicinity of a rear window of an automobile and displays image information to the outside.

11. A head up display unit, wherein the head up display device as set forth in claim 1 is part or all of a windshield of an automobile.

12. A head up display unit, wherein the head up display device as set forth in claim 1 is part or all of a rear window of an automobile.

13. The head up display unit as set forth in claim 1, wherein said light from said light supply means is free of traveling through said image information display means.

14. The head up display unit as set forth in claim 1, wherein said light supply means is directly facing said image information display means.