Display device

Patent metadata

Field	Value
Publication number	US-2016116768-A1
Application number	US-201514883834-A
Country	US
Kind code	A1
Filing date	Oct 15, 2015
Priority date	Oct 22, 2014
Publication date	Apr 28, 2016
Grant date	—

Abstract

A display device includes a light modulation layer and a light source. The light modulation layer is disposed between a pair of transparent substrates, has determined refractive index anisotropy, and includes plural light modulation elements which differ in responsiveness to an electric field generated by electrodes formed on a transparent substrate. The light source emits light of a determined color incident on the light modulation layer from a side of the light modulation layer. When the electric field is not generated, the light modulation layer transmits the incident light emitted from the light source. When the electric field is generated, the light modulation layer scatters the incident light and emits scattered light to a transparent substrate.

First claim

The invention is claimed as follows:

1 . A display device comprising:
a light modulation layer disposed between a pair of transparent substrates, the light modulation layer having determined refractive index anisotropy and including plural light modulation elements, wherein the plural light modulation elements differ in responsiveness to an electric field generated by electrodes formed on a transparent substrate; and a light source which emits light of a determined color incident on the light modulation layer from a side of the light modulation layer, wherein: when the electric field is not generated, the light modulation layer transmits the incident light emitted from the light source; and when the electric field is generated, the light modulation layer scatters the incident light and emits scattered light to a transparent substrate.

2 . The display device according to claim 1 , wherein:
outer surfaces of the pair of transparent substrates on opposite sides of the light modulation layer are open; and when the electric field is not generated in the light modulation layer, the light modulation layer transmits the light which travels in a piercing direction,
wherein the transparent substrate and the light modulation layer are pierced in the piercing direction, and
wherein the light modulation layer transmits the light which enters the light modulation layer from one outer surface of the pair of transparent substrates, and emits the light to an outer side of the pair of transparent substrates.

3 . The display device according to claim 1 , wherein:
the electrodes generate the electric field in display units obtained by dividing a display area; the light source includes plural color light sources, wherein the plural color sources operate independently of one another, and the plural color sources emit lights of different colors to the display units; and the display device includes a drive section, the drive section
acquiring color information for the display area,
lighting the color light sources corresponding to the color information, and
according to the display units on the basis of the color information, synchronizing the lighting of the color light sources corresponding to the color information with applying voltage to the electrodes.

4 . The display device according to claim 3 , wherein,
according to color components included in the color information, the drive section
lights the color light sources corresponding to the color components to emit lights of the color components so that the lights enter a planar area of the light modulation layer, and
sequentially applies the voltage to the electrodes in the display units.

5 . The display device according to claim 3 , wherein,
according to display unit groups each including the display units, wherein the display units are arranged in a direction in which light is emitted from the color light sources, the drive section
lights the color light sources corresponding to color components to emit lights of the color components so that the lights enter areas of the light modulation layer corresponding to the display unit groups, and
sequentially applies the voltage to the electrodes in the display units included in the display unit groups.

6 . A display device comprising:
a light modulation layer disposed between a pair of transparent substrates, the light modulation layer having determined refractive index anisotropy and including plural light modulation elements, wherein the light modulation elements differ in responsiveness to an electric field generated by electrodes formed on a transparent substrate; an external light source which emits light of a determined color incident on the light modulation layer from outside the transparent substrate; and a drive section
acquiring color information for a display area, and
synchronizing lighting of the external light source with applying of voltage to the electrodes on the basis of the color information;
wherein:
when the electric field is not generated, the light modulation layer transmits the incident light emitted from the external light source; and
when the electric field is generated, the light modulation layer scatters the incident light and emits scattered light to a transparent substrate.

7 . The display device according to claim 6 , comprising a light source which emits light of a determined color incident on the light modulation layer from a side of the light modulation layer,
wherein the drive section synchronizes lighting of the external light source and the light source with applying of voltage to the electrodes on the basis of the color information.

8 . A display device comprising:
a first display panel and a second display panel each including: a light modulation layer which is disposed between a pair of transparent substrates, the light modulation layer including a first light modulation element and second light modulation elements, wherein the first light modulation element and the second light modulation elements each have determined refractive index anisotropy, wherein responsiveness of the second light modulation elements to an electric field generated by electrodes formed on a transparent substrate is higher than responsiveness of the first light modulation element to the electric field, wherein tilt directions of the second light modulation elements responding to the electric field align, wherein the first display panel and the second display panel are stacked so that the tilt directions in the first display panel and the tilt directions in the second display panel are the same, and wherein, when the electric field is not generated, each of the first display panel and the second display panel transmits incident light, and when the electric field is generated, each of the first display panel and the second display panel transmits an incident light component whose polarization direction is the same as the tilt directions, and scatters incident light components whose polarization directions are different from the tilt directions, so that the polarized light polarized in a direction corresponding to the tilt directions is emitted to one of the transparent substrates.

9 . The display device according to claim 8 , wherein the first display panel:
includes a light source which emits light of a determined color incident on the light modulation layer from a side of the light modulation layer; and is disposed on a back side of the second display panel.

10 . The display device according to claim 8 , comprising a phase difference plate which changes a polarization plane of the incident light, and, which is disposed between the first display panel and the second display panel.

Assignees

• Japan Display Inc

Inventors

• Okuyama Kentaro
• Sakaigawa Akira

Classifications

• G02F1/133615

  Edge-illuminating devices, i.e. illuminating from the side · CPC title

• G02F1/1334 Primary

  based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals · CPC title

• G02F2001/13756

  Physics · mapped topic

• G02F1/137 Primary

  characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering · CPC title

• G02F1/133621

  providing coloured light (G02F1/133617, G02F1/133533 take precedence) · CPC title