Mirror display, half mirror plate, and electronic device

• US 10,146,086 B2
• Filed: 07/24/2014
• Issued: 12/04/2018
• Est. Priority Date: 08/05/2013
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Sakai, Akira, Hasegawa, Masahiro, Hakoi, Hiroyuki, Yoshida, Hidefumi, Mizushima, Shigeaki
• Primary Examiner(s): DUONG, THOI V
• Application Number:
  US14/909,545
• Publication Number:
  US 20160178964A1
• Time in Patent Office: 1,594 Days
• CPC Class Codes: G02B 27/145 having sequential partially reflecting surfaces
• CPC Class Codes: G02B 27/286 for controlling or changing the state of polarisation, e.g. transforming one polarisation state into another G02B5/3083 takes precedence; light guide coupling means utilising polarising elements G02B6/34
• CPC Class Codes: G02B 5/3016 involving passive liquid crystal elements optical properties of liquid crystals G02F1/0063; polarising elements associated with active liquid crystal devices G02F1/133528
• 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 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133557 Half-mirrors
• CPC Class Codes: G02F 1/133562 on the viewer side
• CPC Class Codes: G02F 1/133638 Waveplates, i.e. plates with a retardation value of lambda/n
• CPC Class Codes: G06T 11/001 Texturing; Colouring; Generation of texture or colour inpainting G06T5/77
• CPC Class Codes: G06T 11/40 Filling a planar surface by adding surface attributes, e.g. colour or texture
• CPC Class Codes: G06T 3/60 Rotation of whole images or parts thereof
• CPC Class Codes: G09G 2340/04 Changes in size, position or resolution of an image
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/36 using liquid crystals
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers

Abstract

The present invention provides a mirror display that sufficiently prevents a decrease in the screen luminance in the display mode while sufficiently increasing the reflectance in the mirror mode, and also gives excellent production efficiency. The mirror display includes a half mirror plate including at least two half mirror layers; and a display device arranged on the backside of the half mirror plate, the display device including a polarizer, the at least two half mirror layers including at least one reflective polarizer, the transmission axis of the polarizer and the transmission axis of the at least one reflective polarizer being substantially parallel to each other or substantially perpendicular to each other, the mirror display configured to switch a display mode allowing display light to be emitted from the display device and to pass through the half mirror plate and a mirror mode preventing display light from being emitted from the display device, the mirror display exhibiting a sum of the transmittance in the display mode and the reflectance in the mirror mode of 100% or higher.

Claims

1. A mirror display comprising:

a half mirror plate including at least two half mirror layers; and

a display device arranged on the backside of the half mirror plate, wherein

the display device includes a polarizer,

the at least two half mirror layers include a first reflective polarizer and a second reflective polarizer,

the half mirror plate includes, in an order from the display device side, the first reflective polarizer, a retarder, and the second reflective polarizer,

the retarder has a slow axis in an in-plane direction,

the transmission axis of the first reflective polarizer and the transmission axis of the second reflective polarizer are substantially parallel to each other,

the transmission axis of the polarizer is substantially parallel to or substantially perpendicular to the transmission axis of the first reflective polarizer and the transmission axis of the second reflective polarizer,

the mirror display switches between a display mode allowing display light to be emitted from the display device and to pass through the half mirror plate and a mirror mode preventing display light from being emitted from the display device,

the mirror display exhibits a sum of the transmittance in the display mode and the reflectance in the mirror mode of 100% or higher.

2. The mirror display according to claim 1,

wherein the retarder is a λ

/2 plate.

3. The mirror display according to claim 1,

wherein the retarder is a λ

/4 plate.

4. The mirror display according to claim 1,

wherein the retarder is a polyethylene terephthalate film.

5. The mirror display according to claim 1,

wherein the display device is a liquid crystal display device.

6. The mirror display according to claim 5, wherein

the liquid crystal display device includes, in an order from the half mirror plate side, a first polarizer, a liquid crystal layer, and a second polarizer, and

the transmission axis of the first reflective polarizer and the transmission axis of the second reflective polarizer are substantially perpendicular to the transmission axis of the second polarizer and substantially parallel to the transmission axis of the first polarizer.

7. An electronic device, comprising:

the mirror display according to claim 1; and

a control device that controls a display region facing the display device by dividing the display region into multiple domains, wherein

the control device changes the range and position of displaying an image by selecting a domain to display an image among the multiple domains.

8. The electronic device according to claim 7,

wherein the range of displaying an image is changeable in response to pinch-in and pinch-out gestures.

9. The mirror display according to claim 1,

wherein the azimuth angle of the slow axis of the retarder is different from the azimuth angle of the transmission axis of each of the first reflective polarizer and the second reflective polarizer.

10. A mirror display comprising:

a half mirror plate including at least two half mirror layers and a depolarization layer between the at least two half mirror layers; and

a display device arranged on the backside of the half mirror plate, wherein

the display device includes a polarizer,

the depolarization layer includes a diffusion adhesive layer,

the at least two half mirror layers include at least one reflective polarizer,

the transmission axis of the polarizer and the transmission axis of the at least one reflective polarizer are substantially parallel to each other or substantially perpendicular to each other,

the mirror display switches between a display mode allowing display light to be emitted from the display device and to pass through the half mirror plate and a mirror mode preventing display light from being emitted from the display device,

the mirror display exhibits a sum of the transmittance in the display mode and the reflectance in the mirror mode of 100% or higher.

11. The mirror display according to claim 10,

wherein the display device is a liquid crystal display device.

12. The mirror display according to claim 11, wherein

the liquid crystal display device includes, in an order from the half mirror plate side, a first polarizer, a liquid crystal layer, and a second polarizer, and

the transmission axis of the at least one reflective polarizer is substantially perpendicular to the transmission axis of the second polarizer and substantially parallel to the transmission axis of the first polarizer.

13. An electronic device, comprising:

the mirror display according to claim 10; and

a control device that controls a display region facing the display device by dividing the display region into multiple domains, wherein

the control device changes the range and position of displaying an image by selecting a domain to display an image among the multiple domains.

14. The electronic device according to claim 13,

wherein the range of displaying an image is changeable in response to pinch-in and pinch-out gestures.