Image display mirror for a vehicle

• US 9,616,816 B2
• Filed: 02/01/2016
• Issued: 04/11/2017
• Est. Priority Date: 02/02/2015
• Status: Active Grant

• Current Assignee: Nitto Denko Corporation
• Original Assignee: Nitto Denko Corporation
• Inventors: Kitamura, Yoshitsugu, Kimura, Keisuke, Takada, Katsunori, Kameyama, Tadayuki, Kuramoto, Hiroki
• Primary Examiner(s): Won, Bumsuk
• Assistant Examiner(s): Washington, Tamara Y
• Application Number:
  US15/011,853
• Publication Number:
  US 20160221508A1
• Time in Patent Office: 435 Days
• Field of Search: 348739, 348E05001, 345 7, 340 571, 359247, 359493, 35948801, 156 60
• CPC Class Codes: B60R 1/083 Anti-glare mirrors, e.g. "day-night" mirrors
• CPC Class Codes: B60R 1/084 using a removable filtering or hiding screen associated with windows or windscreens B60J3/00
• CPC Class Codes: B60R 1/088 using a cell of electrically changeable optical characteristic, e.g. liquid-crystal or electrochromic mirrors
• CPC Class Codes: B60R 1/12 Mirror assemblies combined with other articles, e.g. clocks
• CPC Class Codes: B60R 2001/1215 with information displays
• CPC Class Codes: G02B 27/144 using partially transparent surfaces without spectral selectivity G02B27/147 takes precedence
• CPC Class Codes: G02B 27/281 used for attenuating light intensity, e.g. comprising rotatable polarising elements
• CPC Class Codes: G02B 5/3083 Birefringent or phase retarding elements G02B5/3008, G02B5/3016 take precedence; systems for polarisation control G02B27/286; manufacturing phase modulating patterns by lithographic processes G03F7/001
• CPC Class Codes: G02F 1/133545 Dielectric stack polarisers
• CPC Class Codes: G02F 1/133553 Reflecting elements associated to illuminating devices G02F1/133605

Abstract

Provided is an image display mirror that includes a half mirror and an image display apparatus, reduces an influence of a reflected image provided by the half mirror, and is excellent in visibility of an image displayed on the image display apparatus. The image display mirror for a vehicle includes a first polarizing plate that is arranged removably and attachably, a half mirror that has a reflection axis and is configured to reflect polarized light, and an image display apparatus in the stated order from a viewer side, in which: the first polarizing plate has a polarizer; and when the first polarizing plate is in an attached state, an absorption axis of the polarizer and the reflection axis of the half mirror are parallel to each other.

Claims

1. An image display mirror for a vehicle, comprising:

a first polarizing plate arranged removably and attachably;

a half mirror having a reflection axis and being configured to reflect polarized light; and

an image display apparatus in the stated order from a viewer side, wherein;

the first polarizing plate has a polarizer; and

when the first polarizing plate is in an attached state, an absorption axis of the polarizer and the reflection axis of the half mirror are parallel to each other.

2. The image display mirror for a vehicle according to claim 1, wherein:

attached and removed states of the first polarizing plate are switched when an image is displayed on the image display apparatus and when the image is not displayed thereon; and

when the image is displayed, the first polarizing plate is arranged between the half mirror and a viewer.

3. The image display mirror for a vehicle according to claim 1, wherein the first polarizing plate is subjected to a low-reflection treatment.

4. The image display mirror for a vehicle according to claim 1, further comprising a λ

/4 plate on a viewer side of the first polarizing plate.

5. The image display mirror for a vehicle according to claim 1, wherein:

the image display apparatus comprises a liquid crystal display apparatus including a liquid crystal cell; and

the liquid crystal display apparatus is free of a polarizing plate on a viewer side of the liquid crystal cell.

6. A method by which a driver of a vehicle observes surroundings of the vehicle with the image display mirror for a vehicle of claim 1, the method comprising:

switching attached and removed states of the first polarizing plate when an image is displayed on the image display apparatus and when the image is not displayed thereon; and

arranging, when the image is displayed, the first polarizing plate between the half mirror and the driver of the vehicle.