JP2003515765A - Display system - Google Patents

Abstract

According to the invention, in an electronic device having a display unit (11), the display (11) includes at least two interfaces (38, 39), each of which has one display control unit (38). 30, 31). The electronic device further includes an arbitrator (42), thereby resolving access conflicts between the interfaces (30, 31). The arbitrator (42) can be configured as switch means in the display unit or software communication means between the display control units. Desirably, the overlapping areas (40, 41) of the display unit (11) are controlled by the interface (30; 31). One interface (39) is slow, for example accessed via a serial connection, and is responsible for displaying information during standby or inactive periods in situations requiring only a limited information display. During such a period, it is desirable that the display control unit (31) of the other interface (38) and related circuits be turned off. This interface (38) is preferably of a high-speed type, for example accessed by a parallel connection and functions when the display unit (11) is fully used.

Description

Detailed Description of the Invention

TECHNICAL FIELD OF THE INVENTION The present invention relates generally to electronic display devices, and more particularly to liquid crystal displays for portable electronic devices.

(Description of Related Art) In today's communication and computer devices, general tendency is miniaturization, power saving,
The focus is on portability. Handheld electronic devices such as handheld computers, mobile phones, cordless phones, etc. have many common aspects and are expected to have even higher throughput. One of the common problems with this type of device is the power supply. Being portable, the power source must rely on batteries or cordless energy transfer, such as solar cells. Batteries are usually relatively bulky and heavy, and even the most advanced batteries have significantly limited device operating time before recharging.

One way to increase the operating time of a battery is to reduce power consumption. Various devices and methods can be utilized to reduce the power required to actually operate the device. Another aspect of power savings is reducing the power required during standby or inactivity. One of the power-hungry ones in typical portable electronic devices is the display unit, typically the LCD unit. There are several ways to save power during periods of inactivity by turning off the display, or a portion of it, or dimming the display illumination. Examples of such solutions are EP-A 0,811,866, US 5,805,121, GB-A 2,
320,591. In the first patent, the actual LCD unit power consumption is saved by turning off part of the LCD display during standby. In the second patent, the power requirement of the LCD unit is saved by reducing the number of pixels.

The power requirements are considerably reduced when using the device according to the above technique. However, it is desirable to further reduce power consumption as much as possible in order to extend the use time of a fully charged battery. Due to recent developments in communication and computer devices, for example, mobile phones for internet connection or high-end portable computers are required to display more and more information, so that the display unit is often large in size, and is used for supplying display information. The processing power required increases. Such a large display unit and the processing unit connected thereto consume more power than, for example, a conventional small mobile phone. Such devices consume too much power even if they utilize state-of-the-art power saving methods. Therefore, there is a general need to further reduce power consumption in portable electronic devices.

Overview A common problem with prior art portable electronic devices with a display is that they consume too much power compared to the required battery life.

Therefore, a general object of the invention is to reduce the power consumption of an electronic device with an information display. Another object of the invention is to reduce the power requirements of standby or inactivity. Another object of the present invention is to reduce the power consumption of the equipment associated with the operation of the display unit, not necessarily the display unit itself.

The above objective is accomplished by a device and method as claimed. According to the invention, in an electronic device generally comprising a display unit, the display unit comprises at least two interfaces which are each controlled by a display control unit. The electronic device also includes an arbitrator that resolves access conflicts between interfaces. The arbitrator can be configured as a switching means of the display unit or a software communication means between the display control units. It is desirable for the interface to control the overlapping areas of the display unit.
One of the interfaces can be accessed as slow or low bandwidth, eg via a serial connection, to manage the information display during idle or inactive periods when only a limited information display is needed Is. During such periods, it is desirable that the display control unit of the other interface and its associated circuitry be in the off state. Other interfaces are preferably accessed with a high speed or bandwidth type, eg parallel connections, to manage full utilization of the display unit.

An advantage of the present invention is that it is possible to turn off the power consuming components used to control the display unit in active mode during standby or inactive periods. This is because the display control is performed by a low power consumption alternative display control unit having a separate interface.

Other advantages and features of the present invention will become apparent in the detailed description of the preferred embodiment which follows. The invention, and other objects and advantages relating to the invention, can be more fully understood from the following description set forth in the accompanying drawings.

(Detailed Description of Embodiments) In order to clarify the features of the present invention described later, a device according to the related art will be described first. FIG. 1 schematically shows an example of a mobile phone according to the prior art. This mobile telephone has a function that enables connection to the Internet network, for example. The display device 10 comprises a display unit 11 controlled by a display control unit 12, which in this example is part of the CPU 13. The display control unit 12 is connected to the display unit interface 14 via a connection point 15. The CPU 13 is used, for example, to process a large amount of information necessary for internet access. The CPU 13 is connected to memory devices 20, 21 such as random access memories. To communicate with any communication network, the telephone is equipped with a radio unit 18 and an antenna 19 for transmitting and receiving radio signals. The wireless unit is connected to the baseband controller 17, and the baseband controller is connected to the CPU 13. Various types of interfaces 14 are possible, for example a partial screen solution in which the active part of the display 16 changes with time depending on the current operating mode.

In such a device, there are four main things that require electric power, that is, a wireless unit 18, a baseband controller 17, and a CPU including an accessory.
13 and the display unit 11. For example, the power saving of the display 11 has been sufficiently advanced by using a partial screen solution or the like. The power consumption of the wireless unit 18 depends mainly on the efficiency of the antenna function, which is not mentioned here. The power consumption of the baseband controller 17 is very limited and does not require urgent measures. However, CPUs require large amounts of power, especially when used in devices that perform advanced tasks such as Internet access. In order to reduce the total power consumption, the CPU is turned off, for example during the waiting period. However, the display unit requires regular operation in order to maintain some simple information display, such as time, date, signal strength, battery charge status, etc. This standby information update is normally performed by activating the CPU unit 13, sending required information to the display interface 14, and turning off the CPU 13 again. However, in general, this procedure requires, for example, the memories 20 and 21, and wasteful power is consumed as a whole.

The basic idea of the invention is to provide the display unit with an additional interface and control unit to enable power-saving display access. This concept is based on the active mode of bright display operation and sparse.
) It can be applied to any type of electronic device with a display that operates in a standby mode of display operation. To achieve this, at least two interfaces must be provided on the display unit. Due to the existence of LCD units today, it is possible to choose to use the interface as either a serial interface or a parallel interface, but these interfaces are mutually exclusive because the interface selection is made when the physical hardware is connected. It becomes the target.

FIG. 2 shows an embodiment of the display device 10 according to the present invention. The display device 10 includes a display unit 11, which is preferably an LCD (liquid crystal display) unit. The display unit 11 includes a first interface 39 and a second interface 38. The first interface 39 is connected to the first display control unit 3 via the first display connection 34.
0, the second interface 38 is connected to the second display control unit 31 via the second display connection 33. In this embodiment, the second display control unit 31 is constructed as a part of the CPU 32. The control units 30 and 31 are preferably composed of microprocessors. CPU32
The first display control unit 30 and the first display control unit 30 are connected to each other by an interconnect 37, and both are part of the same processing unit 35, but each part operates independently of each other. The waiting information is provided to the first display control unit via connection 36. Sources of the standby information are the processing unit 35, the display device 10,
Or it can be considered as an external source.

The first interface 39 of the display unit 11 is configured to operate the display unit 11 and access a first display area 41 of the display when in the first display mode. Similarly, the second interface 38 of the display unit 11 is configured to operate the display unit 11 and access the second display area 40 of the display when in the second display mode. The first display area 41 and the second display area 40 are overlapped with each other, and
Preferably constitutes a sub-region of the second display region 40.

The interfaces 38 and 39 are respectively independent display control units 31,
Since there is 30, there may be contention when accessing the display unit 11. An arbitrator 42 is provided to resolve such conflicts.
In this embodiment, the arbitrator 42 is a double switch controlled by the CPU 32.

When the display needs to be activated, the CPU 32 centrally processes its corresponding data. The second interface 38 operates and the second
The display area 40 of is used. Arbitrator 42 keeps display connection 33 closed, blocking the flow of information to display connection 34. Some information may arrive at the standby information connection 36, but it will be processed by the CPU before being displayed on the display via the second interface 38.

Processing power consumption is reduced during periods of inactivity or standby. A large display area is not needed as there are only a few parameters that need to be displayed. In such a case, the arbitrator 42 transfers the role of display control to the first display control unit 30 to connect the first interface 39. In order to reduce the power consumption, the CPU 32 and the second display control unit 31
Is turned off. During the waiting period, only limited waiting information is received over connection 36. This waiting information is received by the first display control unit 30,
The display is updated according to the information. This means that only the first display control unit 30 having low power consumption operates during the standby period.
When the waiting period ends, the CPU 32 is restarted and restarts the display control function.

Since the first interface 39 is to be used during periods of low activity, the first interface 39
Display connection 34 is preferably a relatively low transmission rate serial connection, ie a low bandwidth connection. In addition, it is desirable to reduce the area of the first display region 41, which also reduces the power consumption of the display unit. It may be desirable to use a partial screen solution. On the other hand, the second interface 38 is to be used during periods of high activity. Therefore, it is desirable that the second connection 33 is a parallel connection, that is, a high-bandwidth connection, which allows the display unit to have a high information rate, since the demand for transferring display information is much higher. Therefore, it is desirable that the second display area 40 is larger than the first display 41. Since there is no conflict when driving the display in two modes, it is possible to overlap the areas 40, 41 with each other, and in order to maximize the utilization of the display unit, the entire first display area 41 is It is preferably covered by two display areas 40.

FIG. 3 shows another embodiment of the display device according to the present invention. Equivalent parts are designated by the same reference numerals and will not be described again. In this embodiment, the standby information is indicated by the power state of the processing unit 35. The battery 45 is connected to a regulator unit 46, from which the operating voltage Vdd is applied to the processing unit through a power supply connection 47. The voltage level of the battery 45 is applied from the voltage level connection 48 to the A / D converter 44 of the processing unit. The output is then supplied to the first display control unit 30. This battery state information is sent to the CPU 32 during periods of high activity.

In the embodiment shown in FIG. 3, the arbitrator is provided in the display unit 11 as the switch 43. This switch is alternately connected to either interface 38, 39. The switch is preferably software controlled, for example by the CPU 32 or the first display control unit 30.

The display device is effectively used in various portable electronic devices. Figure 4a
4c is a schematic diagram of a mobile telephone 50 having an internet access function.
In FIG. 4 a, the telephone 50 is shown in a folded configuration, with the base unit 51 partially covered by a lid 52. A display device 53 is arranged on the front surface of the base unit 51. When the lid 52 is folded on the base unit 51, as shown in FIG.
Only the smaller first portion 54 of the display is visible, as indicated by a. With such a configuration, the telephone can be used as a normal mobile telephone, and the necessary information is displayed on the first portion 54 of the display unit. In FIG. 4 b, the lid 52 is turned away from the base unit 51 to open the telephone 50. In this state, the entire display area 55 of the display device 53 is exposed and, for example, Internet information can be displayed. Figure 4c shows the display portion of the telephone of Figures 4a and 4b. In this figure, the first portion area 54 and the entire display area are drawn together to show the difference in display requirements. Such a telephone would greatly benefit from the display device according to the invention.

FIG. 5 shows a schematic of a mobile telephone according to the present invention. Components equivalent to those included in the display device are designated by the same reference numerals and will not be described again.
The baseband controller 17 is provided with a first display control unit 30, which is connected via a first display connection 34 to a first interface 39 controlling a first area 54 of the display 11. It Similar to the above, the CPU 13 includes a second display control unit 31, which is connected via a second display connection 33 to a second interface 38 which controls a second area 55 of the display 11. Connected. In this embodiment, the arbitrator 60 is configured as a software communication means via an interconnect between the CPU 13 managing the access right to the interfaces 38 and 39 and the baseband controller 17.

When the mobile phone operates in the Internet mode, the CPU 13 is fully utilized and the second display control unit 31 controls the display 11 according to the communication of the arbitrator 60. Full screen operation is possible. When the mobile phone lid is closed and in standby mode, the only information normally displayed is signal strength, battery state of charge, time and date. Such information can be easily supplied from the baseband controller. Therefore, the CPU 13 is turned off and display control passes from the arbitrator 60 to the first display control unit 30. Such turning off of the main CPU 13 during periods of high activity is well known in the art. This makes it possible to utilize the unit first area 54 in the display 11 for displaying the limited required information, which completely eliminates the power consumption of the CPU 13 and the memories 20, 21.

A comparison of the telephones of FIGS. 1 and 5 clearly shows the essence of the invention. The display comprises two interfaces, which are driven by two independent display control units 30,31. One unit 31 is connected to the high activity processing unit 13 that consumes power and accesses the large area display area 55. Since the other unit 30 is independent of the high activity processing unit 13 with power consumption, it is possible to drive the smaller area 54 during low activity periods. As a result, the power consumption is suppressed and at the same time, the battery operating time becomes long.

FIG. 6 shows another device, which is an interesting device that effectively utilizes the display device according to the present invention. The portable computer 70 includes a bottom portion 72 and a top portion 71, which can be folded over each other. The bottom 72 is provided with conventional keys, mouse functions, and the like. A large LCD screen 73 is provided on the upper part. During normal operation, the entire screen area 74 is typically used to display the required information. Computers and displays operate in a high power consumption mode. However, the only information that needs to be updated during periods of inactivity is usually the time and battery charge indicators, which fit into the limited screen area 75. In such a state, it is possible to turn off the main processor to save power, and a simple display control with low power consumption takes charge of updating the standby information.

FIG. 7 shows a preferred embodiment of the display unit according to the present invention. The LCD unit 11 includes an LCD area 53. The LCD area 53 is controlled by the row driver 82 and the column driver 81. The column driver is built in the driver control unit 80. The first interface 39 and the second interface 38 are inputs of the driver control unit 80. The driver control unit further includes a control block 89 and a display RAM 90. In this embodiment, the first interface 39 is configured as a serial interface and comprises a serial data input / output connection 83 and a serial clock connection 84. In this embodiment, the second interface 38 is a parallel interface and comprises a 16-bit bidirectional data bus 85, a command / data select signal connection 86, a read strobe connection 87, and a write strobe connection 88. Therefore, although the interface according to the present invention can be physically connected at the same time, only one of them actually operates at a given time. It is the arbitrator that is configured in the display unit itself or the related unit that performs the arbitration. In the preferred embodiment, block 48 within control block 89 provides arbitration.

FIG. 8 is a flowchart showing a display control method according to the present invention. The process starts at step 100. At step 102, an arbitration process is performed. Now it is determined whether the display is driven in the first mode. If the first mode of operation is selected, the interface of the first display unit is driven in step 104 and its associated display operates in the first mode. However, if the first mode is not selected, the interface of the second display unit is driven in step 106 and its associated display operates in the second mode. The process ends at step 108.
The illustrated process illustrates alternating access to the two display modes and should not be construed as a normal flow chart.

As will be apparent to those skilled in the art, several modifications and variations are possible within the scope of the claims. For example, the principles of interfaces operating independently of each other can be applied to more than two interfaces to adjust display control to several levels of activity. When this is applied to the mobile phone as described above, the first mode can be a pure standby mode, the second mode can be a normal telephone mode, and the third mode can be an internet mode. These modes require different area display areas and different processing powers.

As will be apparent to those skilled in the art, various modifications and changes can be made within the scope of the present invention and are described in the claims.

[Brief description of drawings]

[Figure 1]   FIG. 3 is a block diagram showing an example of a mobile phone according to the related art.

[Fig. 2]   FIG. 3 is a block diagram showing an embodiment of a display device according to the present invention.

[Figure 3]   FIG. 8 is a block diagram showing another embodiment of the display device according to the present invention.

Figure 4a   The figure which shows the mobile telephone in a folded state.

Figure 4b   The figure which shows the mobile telephone of an open state.

FIG. 4c   FIG. 5b shows a part of the mobile telephone shown in FIGS. 4a and 4b.

[Figure 5]   FIG. 3 shows a mobile phone according to the present invention.

[Figure 6]   FIG. 3 shows a portable computer according to the present invention.

[Figure 7]   FIG. 3 is a diagram showing a display unit according to the present invention.

[Figure 8]   6 is a flowchart showing a display control method according to the present invention.

[Procedure for Amendment] Submission for translation of Article 34 Amendment of Patent Cooperation Treaty

[Submission date] June 13, 2001 (2001.6.13)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Contents of correction]

[Claims]

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G09G 3/20 680 G09G 3/20 680D 680T (81) Designated country EP (AT, BE, CH, CY, DE) , DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE, TR), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW , ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, MZ, SD, SL, SZ, TZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AG, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, BZ, C , CH, CN, CR, CU, CZ, DE, DK, DM, DZ, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MA, MD, MG, MK, MN, MW, MX, MZ, NO, NZ, PL, PT, RO , RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, TZ, UA, UG, UZ, VN, YU, ZA, ZW [Continued Summary] It is accessed by the connection and works when the display unit (11) is fully used.

Claims (36)

[Claims] 1. A display device (10) having a display unit (11; 53; 73), said display unit (11; 53; 73).
Is the same driver (8) as the display (53) and the drivers (81, 82).
1, 82) connected to at least a first interface (39) and a second interface (38), said first interface (39) being connected to a first display control unit (30), The second interface (3
Display device (8) is connected to a second display control unit (31), and arbitration between the interfaces (38, 39) is performed by an arbitrator (60). 2. The software controlled arbitrator (4)
2; 43; 48; 60). 3. The arbitrator comprises the display unit (11; 5).
Display device according to claim 2, characterized in that it is a switch (43) in 3; 73). 4. The display control unit (30) wherein the arbitrator is
Display device according to claim 2, characterized in that it comprises a communication means (60) between the two. 5. Areas (40, 41; 53; 54) where the interfaces (38, 39) overlap each other on the display unit (11; 53; 73).
74, 75) for controlling the display device according to any one of claims 1 to 4. 6. Display device according to claim 1, characterized in that said first interface (39) is a low bandwidth interface. 7. A display device according to claim 6, wherein the first interface (39) is a serial interface. 8. A display device according to claim 1, wherein the second interface (38) is a high bandwidth interface. 9. A display device according to claim 8, characterized in that said second interface (38) is a parallel interface. 10. Display device according to any of the preceding claims, characterized in that the second display control unit (31) and associated means are switched off during periods of inactivity. 11. The display device according to claim 1, wherein at least one of the display control units (30, 31) is a microprocessor. 12. The display control unit (30, 31) is configured as an independent means in the same processing unit (35).
1. The display device according to 1. 13. The display device according to claim 1, wherein the display unit (11; 53; 73) is a liquid crystal display. 14. A display device according to claim 1, wherein the first interface (39) is arranged to drive the display unit (11; 53; 73) in a partial display mode. Display device. 15. A portable electronic device (10) having a display unit (11; 53; 73), said display unit (11; 53; 73).
Is the same driver (8) as the display (53) and the drivers (81, 82).
1, 82) connected to at least a first interface (39) and a second interface (38), said first interface (39) being connected to a first display control unit (30), The second interface (3
A portable electronic device, characterized in that 8) is connected to a second display control unit (31) and arbitration between the interfaces (38, 39) is performed by an arbitrator (60). 16. The software-controlled arbitrator comprises:
42; 43; 48; 60). 17. The portable electronic device according to claim 16, wherein the arbitrator is a switch (43) in the display unit. 18. The display control unit (3) comprising: the arbitrator.
Portable electronic device according to claim 16, characterized in that it comprises means (60) for communication between 0, 31). 19. Areas (40, 41; 53; 5) in which the interfaces (38, 39) overlap one another on the display unit (11; 53; 73).
4; 74, 75). 19. A portable electronic device according to any one of claims 15 to 18, characterized in that 20. Portable electronic device according to any of claims 15 to 19, characterized in that the first interface (39) is a low bandwidth interface. 21. Portable electronic device according to claim 20, characterized in that said first interface (39) is a serial interface. 22. Portable electronic device according to any of claims 15 to 21, characterized in that said second interface (38) is a high bandwidth interface. 23. Portable electronic device according to claim 22, characterized in that said second interface (38) is a parallel interface. 24. Portable electronic device according to any of claims 15 to 23, characterized in that the second display control unit (31) is turned off during periods of inactivity. 25. At least one of the display control units (30, 31) comprises a microprocessor.
A portable electronic device according to any one of 1. 26. Portable electronic device according to claim 25, characterized in that the display control unit (30, 31) is configured as an independent means in the same processing unit (35). 27. Portable electronic device according to any of claims 15 to 26, characterized in that the display unit (11; 53; 73) is a liquid crystal display. 28. One of the claims 15 to 27, characterized in that the first interface (39) is arranged to drive the display unit (11; 53; 73) in a partial display mode. A portable electronic device as described. 29. A display (53) and a driver (81, by means of a first display control means (30) via a first interface (39).
Driving the display unit (11; 53; 73) including 82) in the first mode, and second display control means (31) via the second interface (38).
A method of controlling display, comprising: driving the display unit (11; 53; 73) in a second mode according to, and performing arbitration between the first and second modes. 30. The method further comprising turning off the second display control means (31) when the display unit (11; 53; 73) is driven in the first mode. 30. The method according to claim 29. 31. The first and second modes are associated with regions (40, 41; 53, 54; 74, 75) that overlap each other on the display unit (11; 53; 73). The method according to claim 29 or 30. 32. The method of claim 29, 30, 31 wherein the first mode comprises a partial display mode. 33. The step of switching from the first mode to the second mode when the inactive state of the second display control means (31) continues for a predetermined period is included in the arbitration step. Claim 29
The method according to any one of 1 to 32. 34. A liquid crystal display unit (11; 53; 73) having a display (53) and a driver (81, 82), comprising at least two physically connectable interfaces (38; 39). And both interfaces (38; 39) are connected to the same driver (81, 82). 35. A liquid crystal display device according to claim 34, characterized in that the interfaces (38; 39) are accessed alternately. 36. Liquid crystal display areas (40, 41; 5) overlapping each other
Liquid crystal display device according to claim 34 or 35, characterized in that 3, 54; 74, 75) are controlled by the interface (38; 39).