Liquid crystal device and electronic apparatus

Abstract

A liquid crystal device includes a first substrate having an alignment film; a second substrate disposed opposite the first substrate and having first and second electrodes and an alignment film; a liquid crystal layer disposed between the alignment films of the first and second substrates; a retardation film disposed on a side of the first substrate facing away from the liquid crystal layer; a first polarizer disposed on the side of the first substrate facing away from the liquid crystal layer; and a second polarizer disposed on a side of the second substrate facing away from the liquid crystal layer. The liquid crystal layer is aligned in a direction parallel to the first and second substrates by the alignment films and is driven by an electric field generated between the first and second electrodes. The slow axis of the retardation film is parallel to the transmission axis of the first or second polarizer and is parallel to the alignment direction of the liquid crystal layer. The Nz coefficient and the phase shift Δnd (nm) of the retardation film fall within a range defined on a graph showing Nz coefficients and phase shifts Δnd as points (Nz, Δnd) by linking point A1 (0.3, 68), point A2 (0.5, 175), point A3 (0.7, 215), point A4 (0.7, 332), point A5 (0.5, 365), and point A6 (0.3, 230). The Nz coefficient is defined by the following formula (1):

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.

FIG. 1 is a schematic diagram of a liquid crystal device according to a first embodiment of the invention.

FIG. 2 is a graph showing the viewing-angle characteristics of the liquid crystal device according to the first embodiment.

FIG. 3 is a graph showing a range where an appropriate viewing angle compensation effect can be achieved in the first embodiment.

FIG. 4 is a schematic diagram of a liquid crystal device according to a second embodiment of the invention.

FIG. 5 is a graph showing the viewing-angle characteristics of the liquid crystal device according to the second embodiment.

FIG. 6 is a graph showing a range where an appropriate viewing angle compensation effect can be achieved in the second embodiment.

FIG. 7 is a schematic diagram of a liquid crystal device according to a third embodiment of the invention.

FIG. 8 is a graph showing the viewing-angle characteristics of the liquid crystal device according to the third embodiment.

FIG. 9 is a graph showing a range where an appropriate viewing angle compensation effect can be achieved in the third embodiment.

FIG. 10 is a graph showing a range where an appropriate viewing angle compensation effect can be achieved in a fourth embodiment of the invention.

FIG. 11 is an equivalent circuit diagram of an example of a liquid crystal device according to an embodiment of the invention.

FIG. 12 is a plan view of a subpixel region of the liquid crystal device.

FIG. 13 is a sectional view taken along line XIII-XIII of FIG. 12.

FIGS. 14A to 14C are perspective views of examples of electronic apparatuses according to embodiments of the invention.

FIG. 15 is a schematic diagram of a liquid crystal device for comparison.

FIG. 16 is a graph showing the viewing-angle characteristics of the liquid crystal device.

Claims

1. A liquid crystal device comprising: a first substrate having an alignment film;a second substrate disposed opposite the first substrate and having first and second electrodes and an alignment film;a liquid crystal layer disposed between the alignment films of the first and second substrates, the liquid crystal layer being aligned in a direction parallel to the first and second substrates by the alignment films and driven by an electric field generated between the first and second electrodes;a retardation film disposed on a side of the first substrate facing away from the liquid crystal layer;a first polarizer disposed on the side of the first substrate facing away from the liquid crystal layer; anda second polarizer disposed on a side of the second substrate facing away from the liquid crystal layer;wherein the slow axis of the retardation film is parallel to the transmission axis of the first or second polarizer and is parallel to the alignment direction of the liquid crystal layer; andthe Nz coefficient and the phase shift Δnd (nm) of the retardation film fall within a range defined on a graph showing Nz coefficients and phase shifts Δnd as points (Nz, Δnd) by linking point A1 (0.3, 68), point A2 (0.5, 175), point A3 (0.7, 215), point A4 (0.7, 332), point A5 (0.5, 365), and point A6 (0.3, 230), the Nz coefficient being defined by the following formula (1): Nz=(nx−nz)/|nx−ny|  (1)

2. A liquid crystal device comprising: a first substrate having an alignment film;a second substrate disposed opposite the first substrate and having first and second electrodes and an alignment film;a liquid crystal layer disposed between the alignment films of the first and second substrates, the liquid crystal layer being aligned in a direction parallel to the first and second substrates by the alignment films and driven by an electric field generated between the first and second electrodes;a retardation film disposed on a side of the first substrate facing away from the liquid crystal layer;a first polarizer disposed on the side of the first substrate facing away from the liquid crystal layer; anda second polarizer disposed on a side of the second substrate facing away from the liquid crystal layer;wherein the slow axis of the retardation film is parallel to the transmission axis of the first or second polarizer and is perpendicular to the alignment direction of the liquid crystal layer; andthe Nz coefficient and the phase shift Δnd (nm) of the retardation film fall within a range defined on a graph showing Nz coefficients and phase shifts Δnd as points (Nz, Δnd) by linking point B1 (0.5, 175), point B2 (0.7, 209), point B3 (0.7, 337), and point B4 (0.5, 363), the Nz coefficient being defined by the following formula (1): Nz=(nx−nz)/|nx−ny|  (1)

3. A liquid crystal device comprising: a first substrate having an alignment film;a second substrate disposed opposite the first substrate and having first and second electrodes and an alignment film;a liquid crystal layer disposed between the alignment films of the first and second substrates, the liquid crystal layer being aligned in a direction parallel to the first and second substrates by the alignment films and driven by an electric field generated between the first and second electrodes;a first retardation film disposed on a side of the first substrate facing away from the liquid crystal layer;a second retardation film disposed on the side of the first substrate facing away from the liquid crystal layer;a first polarizer disposed on the side of the first substrate facing away from the liquid crystal layer;a third retardation film disposed on a side of the second substrate facing away from the liquid crystal layer, the third retardation film being equivalent to the second retardation film; anda second polarizer disposed on the side of the second substrate facing away from the liquid crystal layer;wherein the slow axis of the first retardation film is parallel to the transmission axis of the first or second polarizer and is parallel to the alignment direction of the liquid crystal layer; andthe Nz coefficient and the phase shift Δnd (nm) of the first retardation film fall within a range defined on a graph showing Nz coefficients and phase shifts Δnd as points (Nz, Δnd) by linking point C1 (0, 68), point C2 (0.3, 71), point C3 (0.5, 104), point C4 (0.5, 184), point C5 (0.3, 227), and point C6 (0, 162), the Nz coefficient being defined by the following formula (1): Nz=(nx−nz)/|nx−ny|  (1)

4. The liquid crystal device according to claim 1, wherein each subpixel region includes a reflective display region and a transmissive display region.

5. The liquid crystal device according to claim 4, wherein the retardation film is disposed on a display side of the liquid crystal device.

6. An electronic apparatus comprising the liquid crystal device according to claim 1.