LIGHT SOURCE MODULE AND DUAL DISPLAY DEVICE

• US 20200133070A1
• Filed: 10/23/2019
• Published: 04/30/2020
• Est. Priority Date: 10/24/2018
• Status: Active Grant

• Current Assignee: Coretronic Corporation
• Original Assignee: Coretronic Corporation
• Inventors: CHEN, Hui-Chuan, TSAI, Wen-Chin, FANG, Chung-Yang, LIN, Yin-Jen, CHEN, Yu-Fan
• Granted Patent: US 11,016,337 B2
• Time in Patent Office: Days
• CPC Class Codes: G02F 1/133342 for double-sided displays
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/133524 Light-guides, e.g. fibre-optic bundles, louvered or jalousie light-guides
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/1336 Illuminating devices
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133605 including specially adapted reflectors
• CPC Class Codes: G02F 1/133606 including a specially adapted diffusing, scattering or light controlling members
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side
• CPC Class Codes: G02F 1/133636 with twisted orientation, e.g. comprising helically oriented LC-molecules or a plurality of twisted birefringent sublayers
• CPC Class Codes: G02F 1/1396 the liquid crystal being selectively controlled between a twisted state and a non-twisted state, e.g. TN-LC cell G02F1/141 takes precedence

Abstract

A light source module includes a light guide plate, a light source and a light regulating element. The light guide plate has a first light emitting surface and a second light emitting surface, and a light incident surface connected between the first light emitting surface and the second light emitting surface. The second light emitting surface has a plurality of microstructures. The light source is disposed adjacent to the light incident surface. The light regulating element is disposed adjacent to the second light emitting surface. A dual display device including the light source module, a first display panel and a second display panel is also provided. The first display panel is disposed on a side of the light guide plate facing the first light emitting surface. The second display panel is disposed on a side of the light regulating element that is away from the light guide plate.

Claims

1. A light source module, comprising a light guide plate, a light source and a light regulating element, wherein:

the light guide plate has a first light emitting surface and a second light emitting surface opposite to each other and a light incident surface connected between the first light emitting surface and the second light emitting surface, and the second light emitting surface has a plurality of microstructures;

the light source is disposed adjacent to the light incident surface and configured to emit a light to enter the light guide plate through the light incident surface; and

the light regulating element is disposed adjacent to the second light emitting surface and configured to receive the light and regulate a reflectance of the light regulating element for the light.

2. The light source module according to claim 1, wherein the light regulating element comprises a liquid crystal panel, a first polarizing film, and a second polarizing film, the first polarizing film is disposed on a side of the liquid crystal panel away from the light guide plate, the second polarizing film is disposed on the other side of the liquid crystal panel facing the light guide plate, the first polarizing film has a first transmission axis to allows a light in a direction parallel to a polarization direction of the first transmission axis to pass therethrough and to reflect a light in a direction non-parallel to the polarization direction of the first transmission axis, and the second polarizing film has a second transmission axis to allow a light in a direction parallel to the polarization direction of the second transmission axis to pass therethrough.

3. The light source module according to claim 2, wherein the liquid crystal panel is a twisted nematic liquid crystal panel, and the first transmission axis is parallel or perpendicular to the second transmission axis.

4. The light source module according to claim 2, wherein the liquid crystal panel is a birefringence liquid crystal panel and has at least one alignment layer, the at least one alignment layer has an alignment direction, the first transmission axis is parallel or perpendicular to the second transmission axis, and the first transmission axis is parallel or perpendicular to the alignment direction, or has an 45 degrees included angle with the alignment direction.

5. The light source module according to claim 4, further comprising:

a first optical film, disposed adjacent to the first light emitting surface; and

a second optical film, disposed on a side of the light regulating element away from the second light emitting surface.

6. The light source module according to claim 1, wherein the light regulating element comprises a cholesteric liquid crystal panel.

7. The light source module according to claim 1, wherein the light regulating element comprises a polymer-dispersed liquid crystal film.

8. The light source module according to claim 1, further comprising a control unit, wherein the control unit divides the light regulating element into a plurality of regions and can regulate the plurality of regions to have the same or different reflectivity.

9. The light source module according to claim 1, further comprising:

a first optical film, disposed adjacent to the first light emitting surface; and

a second optical film, disposed on a side of the light regulating element away from the second light emitting surface.

10. The light source module according to claim 9, wherein each of the plurality of microstructures has a first surface inclined with respect to the second light emitting surface, the first surface faces the light incident surface, the first optical film is a first reverse prism sheet and comprises a plurality of first prism pillars, the plurality of first prism pillars are arranged along a predetermined direction from the light incident surface toward away from the light incident surface, the plurality of first prism pillars face the first light emitting surface, the second optical film is a second reverse prism sheet and comprises a plurality of second prism pillars, the plurality of second prism pillars are arranged along the predetermined direction and face the second light emitting surface.

11. The light source module according to claim 1, further comprising:

a first optical film, disposed adjacent to the first light emitting surface; and

a second optical film, disposed between the second light emitting surface and the light regulating element.

12. The light source module according to claim 11, wherein each of the plurality of microstructures has a first surface inclined with respect to the second light emitting surface, the first surface faces the light incident surface, the first optical film is a first reverse prism sheet, and comprises a plurality of first prism pillars, the plurality of first prism pillars are arranged along a predetermined direction from the light incident surface toward away from the light incident surface, the plurality of first prism pillars face the first light emitting surface, the second optical film is a second reverse prism sheet and comprises a plurality of second prism pillars, the plurality of second prism pillars are arranged along the predetermined direction and face the second light emitting surface.

13. A dual display device, comprising a light source module, a first display panel and a second display panel, wherein:

the light source module comprises a light guide plate, a light source and a light regulating element, wherein;

the light guide plate has a first light emitting surface and a second light emitting surface opposite to each other, and a light incident surface connected between the first light emitting surface and the second light emitting surface, and the second light emitting surface has a plurality of microstructures;

the light source is disposed adjacent to the light incident surface and configured to emit a light beam to enter the light guide plate through the light incident surface; and

the light regulating element is disposed adjacent to the second light emitting surface and configured to receive the light beam and regulate a reflectance of the light regulating element for the light;

the first display panel is disposed on a side of the light guide plate facing the first light emitting surface; and

the second display panel is disposed on a side of the light regulating element that is away from the light guide plate.