Active matrix organic light-emitting diode display and method of controlling display thereof

• US 8,976,322 B2
• Filed: 07/19/2011
• Issued: 03/10/2015
• Est. Priority Date: 08/06/2010
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Jung Hyun, Kim, Dong Sub
• Primary Examiner(s): Caley, Michael
• Assistant Examiner(s): PAN, JIA X
• Application Number:
  US13/185,700
• Publication Number:
  US 20120033144A1
• Time in Patent Office: 1,330 Days
• Field of Search: 349/1, 349/74, 349/80, 349/115, 345/88, 313/505, 313/506
• US Class Current: 349/74
• CPC Class Codes: G02F 1/13473 for wavelength filtering or for colour display without the use of colour mosaic filters
• CPC Class Codes: G02F 1/13718 based on a change of the texture state of a cholesteric liquid crystal
• CPC Class Codes: G02F 2201/44 Arrangements combining different electro-active layers, e.g. electrochromic, liquid crystal or electroluminescent layers
• CPC Class Codes: G06F 1/3206 Monitoring of events, devices or parameters that trigger a change in power modality
• CPC Class Codes: G06F 1/3265 Power saving in display device
• CPC Class Codes: G06F 3/1431 using a single graphics controller
• CPC Class Codes: G09G 2300/02 Composition of display devices
• CPC Class Codes: G09G 2300/023 Display panel composed of stacked panels
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2360/04 Display device controller operating with a plurality of display units
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 2380/14 Electronic books and readers
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/3225 using an active matrix
• CPC Class Codes: G09G 3/3629 using liquid crystals having memory effects, e.g. ferroelectric liquid crystals
• CPC Class Codes: H10K 59/128 comprising two independent displays, e.g. for emitting information from two major sides of the display
• CPC Class Codes: H10K 59/50 OLEDs integrated with light modulating elements, e.g. with electrochromic elements, photochromic elements or liquid crystal elements

Abstract

An Active Matrix Organic Light Emitting Diode (AMOLED) display and a method of controlling a display thereof are provided. The AMOLED display includes an input unit, a controller, a display unit for displaying a low power mode screen, by enabling the controller to turn off an AMOLED and to turn on a cholesteric Liquid Crystal Display (LCD) in a low power mode, and for displaying a high picture quality mode screen, by enabling the controller to turn on the AMOLED and to turn off the cholesteric LCD in a high picture quality mode. When used in an indoor environment, the AMOLED display can operate in the high picture quality mode, and when used in an outdoor environment or as an e-book reader, the AMOLED display can operate in the low power mode.

Claims

1. An Active Matrix Organic Light Emitting Diode (AMOLED) display comprising an input unit and a controller, the display comprising:

a display unit that displays a low power mode screen, by enabling the controller to turn off an AMOLED and to turn on a cholesteric Liquid Crystal Display (LCD) in a low power mode, and that displays a high picture quality mode screen, by enabling the controller to turn on the AMOLED and to turn off the cholesteric LCD in a high picture quality mode,

wherein the cholesteric LCD is integrally manufactured at an upper surface of the AMOLED, the cholesteric LCD and the AMOLED are integrally manufactured in a stacked configuration, and the integrally manufactured stacked configuration is devoid of a polarization plate,

wherein light emitted from the AMOLED is visibly transmitted through the cholesteric LCD in the high picture quality mode,

wherein the cholesteric LCD comprises three cholesteric liquid crystal color layers, and at least one of the three cholesteric liquid crystal color layers performs a function of a circular polarization plate in the high picture quality mode, and

wherein the controller determines information of a content to be displayed and of an environment of the display, and if the controller determines that at least one of the content to be displayed and the environment of the display requires the high picture quality mode, controls to display the content in the high picture quality mode screen.

2. The display of claim 1, wherein the three cholesteric liquid crystal color layers comprise a first cholesteric liquid crystal color layer stacked at the upper surface of the AMOLED, a second cholesteric liquid crystal color layer stacked at an upper part of the first cholesteric liquid crystal color layer, and a third cholesteric liquid crystal color layer stacked at an upper part of the second cholesteric liquid crystal color layer.

3. The display of claim 2, wherein a first transparent electrode film for fixing the first cholesteric liquid crystal color layer and for applying a voltage is attached to an upper surface of the first cholesteric liquid crystal color layer,

wherein a second transparent electrode film for fixing the second cholesteric liquid crystal color layer and for applying a voltage is attached to an upper surface of the second cholesteric liquid crystal color layer, and

wherein a third transparent electrode film for fixing the third cholesteric liquid crystal color layer and for applying a voltage is attached to an upper surface of the third cholesteric liquid crystal color layer.

4. The display of claim 2, wherein one of the three cholesteric liquid crystal color layers selectively reflects or transmits red color light, another one selectively reflects or transmits green color light, and the remaining one selectively reflects or transmits blue color light.

5. The display of claim 2, wherein the at least one of the three cholesteric liquid crystal color layers comprises a thickness of 14 μ

m or more.

6. The display of claim 5, wherein the at least one of the three cholesteric liquid crystal color layers performing the function of the circular polarization plate totally reflects right circular polarized light.

7. The display of claim 1, wherein the controller determines one of the low power mode and the high picture quality mode in accordance with a user selection input by the input unit.

8. The display of claim 1, wherein the controller determines one of the low power mode and the high picture quality mode in accordance with a content to be displayed on the display.

9. The display of claim 1, wherein the controller determines one of the low power mode and the high picture quality mode in accordance with an environment in which the display is used.

10. The display of claim 1, wherein the cholesteric LCD is devoid of an absorption layer.

11. The display of claim 1, wherein the AMOLED performs a function of an absorption layer that absorbs light for expressing a black color when in the low power mode.