Transflective LCD device with different transmission parts each having a particular transmittance

• US 6,882,389 B2
• Filed: 04/30/2003
• Issued: 04/19/2005
• Est. Priority Date: 03/23/1990
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Oshima, Mitsuaki, Uemura, Tsuyoshi, Kobayashi, Yoshinori, Fujiwara, Shozo, Gohara, Yoshihiro
• Primary Examiner(s): TON, MINH TOAN T
• Application Number:
  US10/425,880
• Publication Number:
  US 20030193634A1
• Time in Patent Office: 720 Days
• Field of Search: 349/113, 349/114
• US Class Current: 349/114
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3218 of display devices
• CPC Class Codes: G06F 1/3265 Power saving in display device
• CPC Class Codes: G06F 1/3287 by switching off individual functional units in the computer system
• CPC Class Codes: G06F 1/3293 by switching to a less power-consuming processor, e.g. sub-CPU
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

A data processing apparatus has a first processing unit for processing an input data, a second processing unit responsive to the data processed by the first processing unit for executing a processing dependent on the data and producing a display data, and a display unit having a display drive unit and a display device for displaying the display data. The second processing unit is selectively inactivated and activated under control of the first processing unit to reduce power consumption in the second processing unit. The display drive unit is also selectively inactivated and activated under control of the first processing unit to reduce power consumption in the display unit. The display device has a memory function that maintains its display image even when supply of a display drive signal from the display drive unit is stopped, so that a latest image before inactivation of the second processing unit and/or the display drive unit for power consumption reduction is visible by an operator during the inactivated and low power consumption state of the apparatus.

Claims

1. A liquid crystal display device comprising:

a liquid crystal layer;

a reflecting layer comprising;

a reflecting part that reflects light, which has reached said reflecting part from a display side through said liquid crystal layer, to the display side through said liquid crystal layer, and

a transmitting part that passes light, which has reached said transmitting part from an opposite side of the display side, to the display side;

a first light transmission part; and

a second light transmission part that transmits a larger amount of light, which has come from the opposite side, to the display side than said first light transmission part,

wherein said reflecting part is formed on said first light transmission part.

2. A liquid crystal display device according to claim 1, wherein said transmitting part is formed on said second light transmission part.

3. A liquid crystal display device according to claim 1, wherein said first light transmission part does not transmit the light, which has come from the opposite side, to the display side.

4. A liquid crystal apparatus comprising:

a liquid crystal display device comprising;

a liquid crystal layer;

a reflecting layer comprising;

a reflecting part that reflects light, which has reached said reflecting part from a display side through said liquid crystal layer, to the display side through said liquid crystal layer, and

a transmitting part that passes light, which has reached said transmitting part from an opposite side of the display side, to the display side;

a first light transmission part; and

a second light transmission part that transmits a larger amount of light, which has come from the opposite side, to the display side than said first light transmission part,

wherein said reflecting part is formed on said first light transmission part; and

a display circuit connected to said liquid crystal display device.

5. A liquid crystal apparatus according to claim 4, wherein said transmitting part is formed on said second light transmission part.

6. A liquid crystal apparatus according to claim 4, wherein said first light transmission part does not transmit the light, which has come from the opposite side, to the display side.