Mirror with built-in display

• US 7,903,335 B2
• Filed: 11/03/2004
• Issued: 03/08/2011
• Est. Priority Date: 11/11/2003
• Status: Expired due to Fees

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Koninklijke Philips N.V.
• Inventors: Nieuwkerk, Armanda Cinderella, Cornelissen, Hugo Johan, Van Delden, Martinus Hermanus Wilhelmus Maria, Peeters, Emiel
• Primary Examiner(s): Pritchett; Joshua L
• APPLICATION: US 20070041096A1
• Time in patent office: 2316 Days
• Field of Search: 359/495, 359/501, 359/502
• US Class Current: 359/489.09
• CPC Class Codes: G02B 5/08 Mirrors vehicle mirrors involving special optical features B60R1/08
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: G02F 1/133622 Colour sequential illumination
• CPC Class Codes: G02F 2001/133622 colour sequential illumination

Abstract

A mirror device which can be simultaneously used for display purposes, based on e.g. an LCD display with a polarizing mirror placed in front of it. The reflectivity of such a mirror display is enhanced by providing at its non-viewing side a further polarizing mirror Color absorption in the display is prevented by placing the color filter or a color (sequential) backlight behind this reflective polarizer at the back of the display.

Claims

1. A polarizing mirror for viewing purposes having:

A first plane reflecting light of a first kind of polarization to a viewing side, the mirror passing light of a second kind of polarization and being provided with a display device at its non-viewing side, the display device having a liquid crystal material between two substrates and being next to the first plane,

wherein the display device during use provides light of the second kind of polarization, the mirror display device having at the non viewing side a further polarizing mirror and color generating means, wherein the further polarizing mirror is positioned directly between an electro-optical layer of the display device and the color generating means including a backlight without any pre-filters therebetween, wherein said polarizing mirror and said display device are rotatable with respect to each other and with respect to an axis substantially perpendicular to the first plane.

2. The polarizing mirror as claimed in claim 1, the color generating means comprising a color sequential backlight.

3. The polarizing mirror as claimed in claim 1, the color generating means comprising a backlight emitting narrow bands of light.

4. The polarizing mirror as claimed in claim 3, the emitting bands of light having a bandwidth of at most 20 nm.

5. The polarizing mirror as claimed in claim 1, the polarizing mirror at its viewing side having switchable polarizing means being switchable between two optical states.

6. The polarizing mirror as claimed in claim 5 in which the switchable polarizing means at its viewing side comprises between two substrates a liquid crystal layer comprising a dye.

7. The polarizing mirror as claimed in claim 5 in which the switchable polarizing means at its viewing side comprises a ½

λ

retarder and a polarizer.

8. A polarizing mirror for reflecting light of a first kind of polarization to a viewing side, and passing light of a second kind of polarization, the polarizing mirror comprising:

a display device at a non-viewing side of the polarizing mirror, the display device having a liquid crystal material between two substrates and being next to the viewing side, wherein the display device during use provides light of the second kind of polarization;

a further polarizing mirror; and

a backlight at the non-viewing side, wherein the further polarizing mirror is positioned directly between an electro-optical layer the display device and the backlight without any pre-filters therebetween, wherein said polarizing mirror and said display device are rotatable with respect to each other and with respect to an axis substantially perpendicular to the first plane.

9. The polarizing mirror of claim 8, wherein the backlight comprises a color sequential backlight.

10. The polarizing mirror of claim 8, wherein the backlight is configured to emit narrow bands of light.

11. The polarizing mirror of claim 10, wherein the narrow bands of light have a bandwidth of at most 20 nm.

12. The polarizing mirror of claim 8, further comprising a switch for on the viewing side switching the polarizing mirror between two optical states.

13. The polarizing mirror of claim 12, wherein the switch comprises a dye between two substrates a liquid crystal layer.

14. The polarizing mirror of claim 12, wherein the switch comprises a ½

λ

.