Polarizer constructions and display devices exhibiting unique color effects

• US 6,768,586 B2
• Filed: 03/26/2003
• Issued: 07/27/2004
• Est. Priority Date: 10/25/1999
• Status: Expired due to Fees

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Kotchick, Keith M., Hibbard, William A., OʼNeill, Mark B., Sahouani, Hassan, Moshrefzadeh, Robert S., Vogel, Kim Marie
• Primary Examiner(s): Chang, Audrey
• Assistant Examiner(s): Curtis, Craig
• Application Number:
  US10/397,485
• Publication Number:
  US 20030184862A1
• Time in Patent Office: 489 Days
• Field of Search: 349/5.96, 349/194, 359/490, 359/491, 359/492, 359/494, 359/498, 359/502
• US Class Current: 359/487.02
• CPC Class Codes: G02B 5/3025 Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state G02B5/3008, G02B5/3016 take precedence
• CPC Class Codes: G02F 1/133533 Colour selective polarisers G02F1/1347 takes precedence
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133626 providing two modes of illumination, e.g. day-night

Abstract

A polarizer construction is disclosed that includes a reflective polarizer disposed on a first side of the construction to transmit light having one polarization and reflect light having an orthogonal polarization, and one or more colored dichroic polarizers disposed on a second side of the construction. The one or more colored dichroic polarizers are arranged so that when the construction is illuminated from the first side, an observer viewing the construction from the second side will observe a first spectral distribution of visible light, and when the construction is illuminated from the second side, an observer viewing the construction from the second side will observe a second spectral distribution of visible light different from the first spectral distribution. Various display constructions using colored polarizers to achieve color changing and image reversal effects are also disclosed.

Claims

1. A transflective liquid crystal display comprising:

a backlight;

a liquid crystal material disposed between a top substrate and a bottom substrate to selectively alter a polarization of light transmitted therethrough;

a transflector disposed between the backlight and the liquid crystal material;

a bottom polarizer disposed between the transflector and the liquid crystal material; and

a top polarizer positioned adjacent to the top substrate,

wherein at least one of the bottom polarizer and top polarizer comprises a guest-host polarizer including a host matrix, one or more first guest dyes disposed in the host matrix and oriented to absorb a first portion of visible, light having a first polarization state, and one or more second guest dyes disposed in the host matrix and oriented to absorb a second portion of visible light having a second polarization state orthogonal to the first polarization state.

2. The transflective display of claim 1, wherein at least one of the bottom polarizer and top polarizer comprises a guest-host polarizer that transmits one color of light of the first polarization state and substantially absorbs all visible light of the second polarization state.

3. The transflective display of claim 1, wherein at least one of the bottom polarizer and top polarizer comprises a guest-host polarizer that transmits a first color of light of the first polarization state and second color of light of the second polarization state.

4. The transflective display of claim 1, wherein the display undergoes an image reversal and color change when switched between a back lit transmissive mode and a front lit reflective mode.

5. The transflective display of claim 1, wherein the transflector comprises a reflective polarizer.

6. The transflective display of claim 5, wherein the reflective polarizer comprises a multilayer birefringent reflective polarizer.

7. The transflective display of claim 5, wherein the reflective polarizer comprises a cholesteric reflective polarizer.

8. The transflective display of claim 5, further comprising a polarization-maintaining diffuser disposed between the reflective polarizer and the bottom polarizer.

9. The transflective display of claim 7, further comprising a quarter wave plate disposed between the cholesteric reflective polarizer and the bottom polarizer.