Display device having reflecting member with multiple reflecting surfaces

• US 7,301,699 B2
• Filed: 01/28/2005
• Issued: 11/27/2007
• Est. Priority Date: 01/28/2004
• Status: Expired due to Fees

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Kanamori, Naohito, Hatanaka, Yayoi
• Primary Examiner(s): Lee; Diane
• Assistant Examiner(s): DO, ROBERT C
• Application Number:
  US11/044,174
• Publication Number:
  US 20050162738A1
• Time in Patent Office: 1,033 Days
• Field of Search: 353 10- 14, 353/69, 340/980, 350/1, 350630-631, 345/1, 345 7- 11, 359/1, 359/449, 359/460, 359630-631
• US Class Current: 359/449
• CPC Class Codes: G02B 2027/0118 comprising devices for improving the contrast of the display / brillance control visibility
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02F 1/133605 including specially adapted reflectors
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side

Abstract

A display device includes a liquid crystal display (LCD) panel, a light emitting diode (LED), and a reflector. The reflector having the first, the second, and the third reflecting surfaces is arranged in the rear of an LCD screen of the LCD panel. The first reflecting surface is arranged parallel to the LCD screen. The light source is arranged between the LCD screen and the LED such that a main axis of light emitted from the LED is parallel to the LCD screen. The second reflecting surface is arranged such that the light is reflected off the second reflecting surface toward the LCD screen. The third reflecting surface is arranged such that the light is reflected off the third reflecting surface toward the first reflecting surface and transmitted to the LCD screen. With this configuration, the amount of the light is less likely to be reduced when the light passes through a light guiding member and the brightness of the LCD screen is increased. Moreover, distances between the first reflecting surface and the LCD screen are about the same in the entire LCD screen, and therefore the brightness of the LCD screen is uniformed.

Claims

1. A display device comprising:

a display member;

a light source arranged in a rear of the display member; and

a reflecting member arranged in the rear of the display member in a manner that the reflecting member covers the display member and reflects light emitted from the light source toward the display member, wherein

the reflecting member includes a first reflecting surface that is arranged substantially parallel to the display member so as to face the display member through air, the first reflecting surface having a first end and a second end opposite each other, a second reflecting surface and a third reflecting surface, the second and the third reflecting surfaces being arranged between the display member and the first reflecting surface,

the second and the third reflecting surfaces are arranged at about the first end of the first reflecting surface in this order from the display member toward the first reflecting surface,

the light source is arranged inside the reflecting member at about the second end of the first reflecting surface to emit light toward a side of the first end with a main light axis of the light substantially parallel to a display screen of the display member,

the display screen is backlighted with light that is transmitted directly from the light source and via the reflecting member,

the second reflecting surface is formed such that the light emitted from the light source is reflected off the second reflecting surface toward the display screen, and

the third reflecting surface is formed such that the light emitted from the light source is reflected off the third reflecting surface toward the first reflecting surface and transmitted to the display screen.

2. The display device according to claim 1, wherein:

the second reflecting surface is sloped toward the light source from a display screen side to the first reflecting surface; and

the third reflecting surface is sloped away from the light source from the display screen side to the first reflecting surface.

3. The display device according to claim 1, wherein the first, the second, and the third reflecting surface are integrally formed.

4. The display device according to claim 1, wherein the reflecting member further includes a fourth reflecting surface abut the second end of the first reflecting surface such that the light emitted from the light source is reflected off the fourth reflecting surface toward the first reflecting surface.

5. The display device according to claim 1, wherein the light source is a light emitting diode.

6. The display device according to claim 1, wherein the display member is a liquid crystal display.

7. A head-up display for a vehicle comprising:

a display member;

a light source arranged in a rear of the display member; and

a reflecting member arranged in the rear of the display member in a manner that the reflecting member covers the display member and reflects light emitted from the light source toward the display member, wherein

the reflecting member includes a first reflecting surface that is arranged substantially parallel to the display member so as to face the display member through air, the first reflecting surface having a first end and a second end opposite each other, a second reflecting surface and a third reflecting surface, the second and the third reflecting surfaces being arranged between the display member and the first reflecting surface,

the second and the third reflecting surfaces are arranged at about the first end of the first reflecting surface in this order from the display member toward the first reflecting surface,

the light source is arranged at about the second end of the first reflecting surface to emit light toward the first end of the first reflecting surface with a main light axis of the light being substantially parallel to a display screen of the display member,

the display screen is backlighted with light that is transmitted directly from the light source and via the reflecting member,

the second reflecting surface is formed such that the light emitted from the light source is reflected off the second reflecting surface toward the display screen, and

the third reflecting surface is formed such that the light emitted from the light source is reflected off the third reflecting surface toward the first reflecting surface and transmitted to the display screen.