HK1087517B - Display system with bi-stable display elements, method of manufacturing the same, and display method - Google Patents

Abstract

The invention comprises systems and methods for partitioning displays, and in particular, displays of interferometric modulator displays. In one embodiment, a display system includes one driving circuit configured to provide signals based on video data intended for display, and a bi-stable display comprising an array having a plurality of bi-stable display elements. The array is configured to display video data using signals received from the driving circuit, and the driving circuit is configured to partition the array into two or more fields, each field including at least one bi-stable display element, and refresh each of the two or more fields in accordance with a refresh rate associated with each field. In another embodiment, a method of displaying data on a display of a client device includes partitioning a bi-stable display of the client device into two or more fields, displaying video data in the two or more fields, and refreshing each of the two or more fields in accordance with a refresh rate that is associated with each field.

Description

Display system having bistable display elements, method of manufacturing the same, and display method

Technical Field

The technical field of the invention relates to micro-electromechanical systems (MEMS).

Background

Microelectromechanical Systems (MEMS) include micromechanical elements, actuators, and electronics. Micromechanical elements may be created using deposition, etching, or other micromachining processes that etch away parts of substrates and/or deposited material layers or that add layers to form electrical and electromechanical devices. One type of MEMS device is known as an interferometric modulator. An interferometric modulator may comprise a pair of conductive plates, one or both of which may be transparent and/or reflective in whole or part and capable of relative motion upon application of an appropriate electrical signal. One of the plates may comprise a stationary layer deposited on a substrate and the other plate may comprise a metal diaphragm separated from the stationary layer by an air gap. Such devices have a wide range of applications, and it would be beneficial in the art to utilize and/or modify the characteristics of these types of devices so that their performance can be exploited in improving existing products and creating new products that have not yet been developed.

Disclosure of Invention

The system, method and apparatus of the present invention have several aspects, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of the invention, its more prominent features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled "detailed description of certain embodiments" one will understand how the features of this invention provide advantages over other display devices.

A first embodiment provides a display system, comprising: at least one drive circuit configured to provide signals for displaying video data; and a display comprising an array of a plurality of bi-stable display elements, the array configured to display video data using signals received from the drive circuit, the array being divided into one or more zones, each zone comprising at least one bi-stable display element and the drive circuit configured to refresh each of the one or more zones according to a refresh rate associated with each zone in one aspect of the first embodiment, in a second aspect, an input device is configured to receive a user selection and the drive circuit is configured to divide the array according to the user selection. And wherein the array is divided into one or more zones, the one or more zones comprising a first zone comprising a first set of interferometric modulators and a second zone comprising a second set of interferometric modulators, in a fifth aspect, the drive circuit is configured to receive at least a portion of the video data from a server in communication with the display system. The at least one interferometric modulator is refreshed with the first set of interferometric modulators during a first refresh cycle, and the at least one interferometric modulator is refreshed with the second set of interferometric modulators during a second refresh cycle, hi a tenth aspect, in an eleventh aspect, the second refresh rate is the same as the first refresh rate, and the refresh of the first region begins at a different time than the refresh of the second region, hi a twelfth aspect, the first refresh rate is determined based at least in part on a frame rate of data displayed in the first region, hi a thirteenth aspect, in a fourteenth aspect, the first refresh rate varies with time.

A second embodiment includes a method of displaying data on a display of a client device, the method comprising: the method includes dividing a bi-stable display of the client device into two or more regions, displaying video data on the two or more regions, and refreshing each of the two or more regions according to a refresh rate associated with each of the two or more regions. The bi-stable display may include an array of interferometric modulators. The embodiment may further comprise receiving at least a portion of the video data from a server. Further, the method may include updating the one or more zones using one or more update schemes. At least one of the one or more update schemes may be selected using a procedure associated with the received data. In this embodiment, refreshing at least one of the two or more regions may include using a refresh rate that is a frame rate based on the data displayed. The method may further include receiving display information including a characteristic of the display and using the display information to select an update scheme.

A third embodiment comprises a communication system for server-based control of a display on a client device, comprising: a communication network; a client device comprising a bi-stable display having a plurality of bi-stable display elements, the client device configured to transmit display information (e.g., one or more characteristics of the bi-stable display) over the communication network; and a server configured to define one or more regions of the bi-stable display, each region having an associated refresh rate, and the server further configured to transmit video data to the client device over the communication network according to the display information, wherein the client device is further configured to receive video data from the server, display the video data on the one or more regions of the display, and update each region using the associated refresh information. In one aspect, the display information includes a display mode. In a second aspect, the display information indicates where the video data should be rendered on the bi-stable display. In a third aspect, the server may be further configured to identify video data to be displayed in each of the two or more regions.

A fourth embodiment includes a data display system, comprising: a content server; in one aspect, the display system may have one or more regions individually addressable by the content server. Wherein the bi-stable display includes a second set of interferometric modulators and a second set of interferometric modulators, the first set of interferometric modulators is associated with the first region and the second set of interferometric modulators is associated with the second region, hi a fifth aspect, the display system may have at least one interferometric modulator from the first set of interferometric modulators assigned to the first plurality of interferometric modulators and the second set of interferometric modulators, hi a sixth aspect, the first region may be configured to update at a first refresh rate and the second region is configured to update at a second refresh rate, hi a seventh aspect, the server is further configured to provide video data to be displayed in each of the one or more regions of a bi-stable display of the client device.

A fifth embodiment comprises a display system comprising means for providing image data signals. The display system further comprises means for dividing a display array comprising a plurality of bi-stable display elements into one or more regions, each region comprising at least one bi-stable display element. The display system further comprises means for displaying the image using the image data signal, wherein each region of the one or more regions is refreshed according to a refresh rate associated with each region.

Drawings

FIG. 1 is a networked system of an embodiment.

FIG. 2 is an isometric view depicting a portion of one embodiment of a display array of interferometric modulators in which a movable reflective layer of a first interferometric modulator is in a released position and a movable reflective layer of a second interferometric modulator is in an actuated position.

FIG. 3A is a system block diagram illustrating one embodiment of an electronic device including a 3 × 3 interferometric modulator display array.

Fig. 3B is a diagram of one embodiment of a client in the server-based wireless network system shown in fig. 1.

FIG. 3C is an exemplary block diagram configuration of the client shown in FIG. 3B.

FIG. 4A is a diagram of movable mirror position versus applied voltage for one exemplary embodiment of an interferometric modulator of FIG. 2.

FIG. 4B is a schematic illustration of a set of row and column voltages that may be used to drive a display array of interferometric modulators.

FIGS. 5A and 5B show an exemplary timing diagram for row and column signals that may be used to write a frame of data to the 33 interferometric modulator display array of FIG. 3A.

FIG. 6A is a cross-sectional view of the interferometric modulator of FIG. 2.

FIG. 6B is a cross-sectional view of an alternative embodiment of an interferometric modulator.

FIG. 6C is a cross-sectional view of another alternative embodiment of an interferometric modulator.

FIG. 7 is a high level flow chart of a client controlled process.

Fig. 8 is a flow diagram of a client-controlled process for initiating and running a receive/display process.

Fig. 9 is a flowchart of a server control process for transmitting video data to a client.

FIG. 10 is a plan view of an embodiment of an interferometric modulator display that may be divided into viewing zones as seen by an observer.

FIG. 11 is a flowchart showing a control process for partitioning the display and setting a refresh rate for each partition.

FIG. 12 is a high level flow diagram of an embodiment of dividing a display into one or more viewing zones and updating each of the one or more viewing zones at a corresponding appropriate update rate.

FIG. 13 is an exemplary diagram of a partitioned display of a client.

Fig. 14 is an example of a message provided by a server.

FIGS. 15A and 15B are system block diagrams illustrating one embodiment of a visual display device comprising a plurality of interferometric modulators.

Detailed Description

The following description is directed to certain specific embodiments. However, the invention can be embodied in a multitude of different ways. Reference in the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrases "in one embodiment," "according to one embodiment," or "in certain embodiments" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. In addition, various features are described which may be exhibited by some embodiments and not by others. Also, various requirements are described which may be requirements for some embodiments but not other embodiments.

In one embodiment, an array of displays on a device includes at least one drive circuit and an array of means (e.g., interferometric modulators) for displaying video data. Video data as used herein refers to any displayable data, including pictures, graphics, and words that may be displayed in the form of still or moving images (e.g., a series of video frames that give the appearance of motion when viewed by a viewer, such as a continuous, changing stock quote display, a "video clip," or data indicating the presence of an action event). Video data as described herein also refers to any kind of control data, including instructions on how to process the video data (display mode), such as frame rate, and data format. The array is driven by a driver circuit to display video data.

In one embodiment, an interferometric modulator is divided into two or more regions. Video data to be displayed in one of the two or more regions may be identified and the video data may be displayed in each of the regions. For displays that do not require frequent updates, refreshing each partition at the refresh rate of the partition itself may save power. In one embodiment, a partitionable display includes an array of interferometric modulators and a drive circuit configured to drive the array, wherein the drive circuit is configured to divide an array of interferometric modulators into two or more regions, identify data to be displayed in one of the two or more regions, and display the identified data in a corresponding region of the divided array, and to update each region of the array at a refresh rate that may be the same as or different from the refresh rate of the other regions. In another embodiment, a method of displaying data includes: receiving video data, identifying video data to be displayed in the two or more regions, displaying the identified data in a corresponding region of the partitioned array, and updating each partition of the display at a refresh rate that depends on the content of the displayed video data.

In the description, reference is made to the drawings wherein like parts are designated with like numerals throughout. The invention may be implemented in any device that is configured to display an image, whether in motion (e.g., video) or stationary (e.g., still image), and whether textual or pictorial. More specifically, the invention may be implemented in or associated with a wide variety of electronic devices such as, but not limited to: mobile telephones, wireless devices, Personal Data Assistants (PDAs), handheld or portable computers, GPS receivers/navigators, cameras, MP3 players, camcorders, game consoles, watches, clocks, calculators, television monitors, flat panel displays, computer monitors, auto displays (e.g., odometer display, etc.), cockpit controls and/or displays, display of camera views (e.g., display of a rear view camera in a vehicle), electronic photographs, electronic billboards or signs, projectors, architectural structures, packaging, and aesthetic structures (e.g., display of images on a piece of jewelry). MEMS devices of similar construction to the MESE devices described herein can also be used in non-display applications such as in electronic switching devices.

Spatial light modulators for imaging applications come in many different forms. Transmissive Liquid Crystal Display (LCD) modulators modulate light by controlling the twist and/or alignment of crystalline materials to block or pass light. Reflective spatial light modulators use different physical effects to control the amount of light reflected to the imaging surface. Examples of such reflective modulators include reflective LCDs and digital micromirror devices.

Another example of a spatial light modulator is an interferometric modulator that modulates light by interference. Interferometric modulators are bi-stable display elements that use an optical resonant cavity with at least one movable or deflectable wall. Constructive interference in the optical cavity determines the color of the visible light emerging from the cavity. When the movable wall (typically constructed at least in part of metal) is moved towards the stationary front face of the cavity, the interference of light within the cavity is modulated and this modulation affects the color of the light exiting at the front face of the modulator. Where the interferometric modulator is a direct-view device, the front surface is typically the surface on which the image seen by the viewer appears.

FIG. 1 shows a networked system according to one embodiment. A server 2, such as a Web server, is operatively coupled to a network 3. Server 2 may correspond to a Web server, mobile phone server, wireless email server, and the like. The network 3 may comprise a wired network or a wireless network, such as a WiFi network, a mobile phone network, a bluetooth network, and the like.

The network 3 may be operatively coupled to a wide variety of devices. Examples of devices that may be coupled to network 3 include computers, such as laptop computer 4, Personal Digital Assistants (PDAs) 5, which may include wireless handheld devices such as Blackberry, Palm Pilot, Pocket PCs, and the like, and mobile phones 6, such as Web-enabled mobile phones, smartphones, and the like. A variety of other devices may also be used, such as a desktop PC, a set-top box, a digital media player, a handheld PC, a Global Positioning System (GPS) navigation device, an in-vehicle display, or other stationary and mobile displays. For ease of discussion, all of these devices are collectively referred to herein as client devices 7.

FIG. 2 illustrates an embodiment of a bi-stable display element comprising an interferometric MEMS display element. In these devices, the pixels are in either a bright or dark state. In the bright ("on" or "open") state, the display element reflects a large portion of incident visible light to the user. When in the dark ("off" or "closed") state, the display element reflects little incident visible light to the user. Depending on the embodiment, the light reflectance properties of the "on" and "off" states may be reversed. MEMS pixels can be configured to reflect predominantly at selected colors, allowing for a color display in addition to black and white.

FIG. 2 is an isometric view depicting two adjacent pixels in a series of pixels of a visual display array, wherein each pixel comprises a MEMS interferometric modulator. In certain embodiments, an interferometric modulator display array comprises a row/column array of these interferometric modulators. Each interferometric modulator includes a pair of reflective layers positioned at a variable and controllable distance from each other to form a resonant optical cavity with at least one variable dimension. In one embodiment, one of the reflective layers is movable between two positions. In the first position, referred to herein as the released state, the movable layer is positioned relatively far from a fixed partially reflective layer. In the second position, the movable layer is positioned closer to the partially reflective layer. Incident light that reflects from the two layers interferes constructively or destructively depending on the position of the movable reflective layer, producing either an overall reflective or non-reflective state for each pixel.

The portion of the pixel array shown in FIG. 2 includes two adjacent interferometric modulators 12a and 12 b. In the interferometric modulator 12a on the left, a movable highly reflective layer 14a is illustrated in a released position at a predetermined distance from a fixed partially reflective layer 16 a. In the interferometric modulator 12b on the right, a movable highly reflective layer 14b is illustrated in an actuated position adjacent to a fixed partially reflective layer 16 b.

The partially reflective layers 16a, 16b are electrically conductive, partially transparent and fixed, and may be fabricated, for example, by depositing one or more layers each of chromium and indium tin oxide on a transparent substrate 20, the layers being patterned into parallel strips, and may form row electrodes in a display device, as will be further described below, the highly reflective layers 14a, 14b may be formed as a series of parallel strips of a deposited metal layer or layers (orthogonal to the row electrodes, partially reflective layers 16a, 16 b) deposited on top of posts 18, and an intervening sacrificial material deposited between the posts 18, after the sacrificial material is etched away, the deformable metal layers are separated from the fixed metal layers by a defined air gap 19. a highly conductive and reflective material such as aluminum may be used for the deformable layers, and the strips may form column electrodes in a display device.

When no voltage is applied, the air gap 19 remains between the layers 14a, 16a, and the deformable layer is in a mechanically relaxed state as shown in the interferometric modulator pixel 12a in FIG. 2. However, after application of a potential difference to a selected row and column, the capacitor formed at the intersection of the row and column electrodes at the corresponding pixel is charged, and electrostatic forces pull the electrodes together. If the voltage is high enough, the movable layer deforms and is forced against the fixed layer (a dielectric material (not shown in this figure) may be deposited over the fixed layer to prevent shorting and control the separation distance), as shown in the interferometric modulator 12b on the right in FIG. 2. The behavior is the same regardless of the polarity of the applied potential difference. As can be seen, the row/column actuation that can control the states of the reflective and non-reflective interferometric modulators is analogous in many ways to that used in conventional LCD and other display technologies.

FIGS. 3-5 illustrate an exemplary process and system for using an array of interferometric modulators in a display application. However, the process and system may also be applied to other displays, such as plasma, EL, OLED, STN LCD, and TFT LCD displays.

Currently, existing flat panel display controllers and drivers are designed to be used almost exclusively with displays that need to be refreshed at all times. Thus, if not refreshed many times in a second, the displayed image on, for example, plasma, EL, OLED, STN LCD, and TFT LCD panels will disappear for a fraction of a second. However, because interferometric modulators of the type described above are capable of maintaining their state without refresh for a longer period of time, wherein the state of the interferometric modulator may remain in one of two states without refresh, a display using interferometric modulators may be referred to as a bi-stable display. In one embodiment, the state of a pixel element is maintained by applying a bias voltage (sometimes referred to as a latch voltage) to one or more interferometric modulators that make up the pixel element.

Generally, a display device typically requires the use of one or more controllers and driver circuits to properly control the display device. Drive circuitry, such as that used to drive an LCD, may be directly coupled to and positioned along the edges of the display panel itself. Alternatively, the driver circuit may be mounted on a flex circuit element that connects the display panel (at its edge) to the rest of an electronic system. In both cases, the driver is typically located at the interface of the display panel with the rest of the electronic system.

FIG. 3A is a system block diagram illustrating certain embodiments of an electronic device that may incorporate various aspects. In the exemplary embodiment, the electronic device includes a processor 21, which may be any general purpose single-or multi-chip microprocessor, such as an ARM,Pro、8051、Or any special purpose microprocessor such as a digital signal processor, microcontroller, or programmable gate array. As is conventional in the art, the processor 21 may be configured to execute one or more software modules. In addition to executing an operating system, the processor may be configured to execute one or more software applications, including a web browser, a telephone application, an email program, or any other software application.

FIG. 3A shows an embodiment of an electronic device that includes a network interface 27 connected to a processor 21, and according to some embodiments may be connected to an array driver 22. the network interface 27 includes appropriate hardware and software to enable the device to interact with another device (e.g., the server 2 of FIG. 1) over a network, the processor 21 is connected to a driver controller 29, which driver controller 29 is in turn connected to an array driver 22 and a frame buffer 28. in some embodiments, the processor 21 is also connected to the array driver 22. the array driver 22 is connected to and drives the display array 30. the components shown in FIG. 3A display a configuration of an interferometric modulator display, however, this configuration may also be used with LCD controllers and drivers in LCDs. as shown in FIG. 3A, the driver controller 29 is connected to the processor 21 over a parallel bus 36, although a driver controller 29 (e.g., such as a driver controller 29 is connected to the processor 21 over a parallel bus 36. As shown in FIGS An LCD controller) is typically associated with the system processor 21 as a stand-alone Integrated Circuit (IC), but these controllers may be constructed in many ways, they may be embedded in the processor 21 as hardware, embedded in the processor 21 as software, or fully integrated in hardware with the array driver 22. in one embodiment, the driver controller 29 receives display information generated by the processor 21, reformats the information appropriately for high speed transmission to the display array 30, and then sends the formatted information to the array driver 22.

The array driver 22 receives the formatted information from the driver controller 29 and reformats the video data into a parallel set of waveforms that are applied many times per second to the hundreds and sometimes thousands of leads coming from the display's x-y array of pixels. Existing flat panel display controllers and drivers, such as those just described, are designed for use almost exclusively with displays that require constant refresh. Because bi-stable displays (e.g., interferometric modulator arrays) do not require such constant refreshing, features that can reduce power requirements can be implemented with bi-stable displays. However, if a bi-stable display is operated using a controller and driver used with an existing display, the advantages of the bi-stable display may not be optimized. Accordingly, it is desirable to have improved controller and driver systems and methods for bi-stable displays. For high speed bi-stable displays, such as the interferometric modulators described above, these improved controllers and drivers preferably implement a low refresh rate mode, a video rate refresh mode, and a unique mode for achieving the unique functionality of the bi-stable modulator. According to the methods and systems described herein, a bi-stable display may be configured to reduce power requirements in various ways.

In one embodiment shown in FIG. 3A, the array driver 22 receives video data from the processor 21 over a data link 31 that bypasses the driver controller 29. Data link 31 may include a serial peripheral interface ("SPI"), an I2C bus, a parallel bus, or any other available interface. In one embodiment shown in FIG. 3A, the processor 21 provides instructions to the array driver 22 to enable the array driver 22 to optimize the power requirements of the display array 30 (e.g., an interferometric modulator display). In an embodiment, video data intended for a portion of a display, e.g., as defined by the server 2, may be identified by packet header information and transmitted over the data link 31. In addition, the processor 21 may route primitives, such as graphics primitives, along data links 31 to the array driver 22. These graphical primitives may correspond to instructions, such as primitives for drawing shapes and text. Still referring to FIG. 3A, in one embodiment, video data may be provided from the network interface 27 to the array driver 22 via a data link 33. In one embodiment, the network interface 27 analyzes the control information transmitted from the server 2 and determines whether the incoming video should be routed to the processor 21 or the array driver 22.

In one embodiment, the video data provided over data link 33 is not stored in frame buffer 28 as is typically the case in many embodiments. It should also be appreciated that in some embodiments, a second drive controller (not shown) may also be used to provide video data to the array driver 22. Data link 33 may include SPI, I2C bus, or any other available interface. The array driver 22 may also include address decoding, row and column drivers for the display, and the like. The network interface 27 may also provide video data directly to the array driver 22 at least partially in response to instructions embedded in the video data provided to the network interface 27. Those skilled in the art will appreciate that arbitration logic may be used to control access by the network interface 27 and the processor 21 to prevent data conflicts at the array driver 22. In one embodiment, a driver running on processor 21 controls the timing of data transmissions from network interface 27 to array driver 22 by allowing the data transmissions during time intervals not normally used by processor 21, such as during time intervals normally used for vertical and/or horizontal blanking delays.

Preferably, this design allows the server 2 to bypass the processor 21 and driver controller 29 and address a portion of the display array 30 directly, for example, in the illustrated embodiment, this allows the server 2 to address a predefined display array area in the display array 30 directly, hi one embodiment, the amount of data transferred between the network interface 27 and the array driver 22 is relatively low, and thus is transferred using a serial bus such as an inter-integrated circuit (I2C) bus or a Serial Peripheral Interface (SPI) bus, however, it should also be appreciated that other circuits will typically be used when other types of displays are utilized, video data provided over the data link 33 can be advantageously displayed without the frame buffer 28 and with little or no intervention from the processor 21.

FIG. 3A also shows an arrangement of the processor 21 coupled to a driver controller 29, such as an interferometric modulator controller. The driver controller 29 is coupled to the array driver 22, which is in turn connected to the display array 30. In this embodiment, the driver controller 29 enables optimization of the display array 30 and provides information to the array driver 22 without having a separate connection between the array driver 22 and the processor 21. In some embodiments, the processor 21 may be configured to communicate with a driver controller 29, and the driver controller 29 may include a frame buffer 28 for temporarily storing one or more frames of video data.

As shown in FIG. 3A, in one embodiment, the array driver 22 includes a row driver circuit 24 and a column driver circuit 26 that provide signals to a pixel display array 30. The cross-section of the array shown in FIG. 2 is shown by line 1-1 in FIG. 3A. For MEMS interferometric modulators, the row/column actuation protocol may take advantage of the hysteresis properties of these devices shown in FIG. 4A. It may require, for example, a 10 volt potential difference to cause a movable layer to deform from the released state to the actuated state. However, when the voltage is reduced from this value, the movable layer will retain its state as the voltage drops back below 10 volts. In the exemplary embodiment shown in FIG. 4A, the movable layer does not release completely until the voltage drops below 2 volts. Thus, in the example shown in FIG. 4A, there is a range of voltage, approximately 3-7 volts, within which there exists a window of applied voltage within which the device is stable in either the released or actuated state. This is referred to herein as the "hysteresis window" or "stability window".

For a display array having the hysteresis characteristics of FIG. 4A, the row/column actuation protocol can be designed to apply a voltage difference of about 10 volts to the pixels to be actuated in the selected pass and a voltage difference of approximately 0 volts to the pixels to be released during row strobing. After the strobe, the pixels are exposed to a steady state voltage difference of about 5 volts such that they remain in whatever state the row strobe put them in. After being written, each pixel sees a potential difference within the "stability window" of 3-7 volts in this example. This feature makes the pixel design shown in fig. 2 stable under the same applied voltage conditions in either an actuated or released pre-existing state. Since each pixel of the interferometric modulator, whether in the actuated or released state, is essentially a capacitor formed by the fixed and moving reflective layers, this stable state can be held at a voltage within the hysteresis window with almost no power dissipation. Essentially no current flows into the pixel if the applied potential is constant.

In typical applications, a display frame may be created by asserting the set of column electrodes in accordance with the desired set of actuated pixels in the first row. A row pulse is then applied to the row 1 electrode, actuating the pixels corresponding to the asserted column lines. The asserted set of column electrodes is then changed to correspond to the desired set of actuated pixels in the second row. A pulse is then applied to the row 2 electrode, actuating the appropriate pixels in row 2 in accordance with the asserted column electrodes. The row 1 pixels are unaffected by the row 2 pulse, and thus remain in the state they were set to during the row 1 pulse. The above steps may be repeated for the entire series of rows in a sequential manner to form the frame. Typically, the frames are refreshed and/or updated with new video data by continually repeating the process at some desired number of frames per second. A wide variety of protocols for driving row and column electrodes of pixel arrays to produce display array frames are also well known and may be used.

FIG. 3B shows an embodiment of a client device 7. exemplary client 40 includes a housing 41, a display 42, an antenna 43, a speaker 44, an input device 48, and a microphone 46. housing 41 is typically made from any of a number of manufacturing processes well known to those skilled in the art, including injection molding and vacuum forming. additionally, housing 41 can be made from any of a number of materials, including but not limited to plastic, metal, glass, rubber, and ceramic, or a combination thereof.

Display 42 of exemplary client 40 may be any of a wide variety of displays, including a bi-stable display as described above with reference to, for example, fig. 2, 3A, and 4-6. In other embodiments, the display 42 comprises a flat panel display, such as the plasma, EL, OLED, STN LCD, or TFT LCD described above, or a non-flat panel display, such as a CRT or other tube device, as is well known to those of skill in the art. However, for purposes of describing the present embodiment, the display 42 comprises an interferometric modulator display, as described herein.

FIG. 3C schematically shows components in an embodiment of exemplary display device 40. The exemplary display client 40 shown includes a housing 41 and may include other components at least partially enclosed within the housing 41. For example, in one embodiment, the exemplary client 2040 includes a network interface 27, the network interface 27 including an antenna 43 coupled to a transceiver 47. The transceiver 47 is connected to the processor 21, which processor 21 is in turn connected to conditioning hardware 52. The conditioning hardware 52 is connected to a speaker 44 and a microphone 46. The processor 21 is also connected to an input device 48 and a driver controller 29. The driver controller 29 is coupled to a frame buffer 28 and to the array driver 22, which in turn is coupled to a display array 30. A power supply 50 provides power to all components as required by the design of this particular exemplary client 40.

The network interface 27 includes the antenna 43 and the transceiver 47 so that the exemplary client 40 can communicate with another device, such as the server 2 shown in fig. 1, over a network 3. In one embodiment, the network interface 27 may also have some processing functionality to reduce the requirements on the processor 21. The antenna 43 is any antenna known to those skilled in the art for transmitting and receiving signals. In one embodiment, the antenna transmits and receives RF signals according to the IEEE802.11 standard, including IEEE802.11 (a), (b), or (g). In another embodiment, the antenna transmits and receives RF signals according to the Bluetooth (BLUETOOTH) standard. In the case of a cellular telephone, the antenna is designed to receive CDMA, GSM, AMPS or other conventional signals used to communicate in a wireless mobile telephone network. The transceiver 47 pre-processes the signals received from the antenna 43 so that they may be received by and further processed by the processor 21. The transceiver 47 also processes signals received from the processor 21 for transmission from the exemplary client 40 via the antenna 43.

The processor 21 generally controls the overall operation of the exemplary client 40, although, as explained in greater detail below, operational control may also be shared with the server 2 (not shown) or given to the server 2. In one embodiment, processor 21 includes a microcontroller, CPU, or logic unit for controlling the operation of exemplary client 40. Conditioning hardware 52 generally includes amplifiers and filters for sending signals to the speaker 44, and for receiving signals from the microphone 46. Conditioning hardware 52 may be discrete components within the exemplary client machine 40, or may be incorporated within the processor 21 or other components.

The input device 48 enables a user to control the operation of the exemplary client 40. In one embodiment, input device 48 includes a keypad (e.g., a QWERTY keyboard or a telephone keypad), a button, a switch, a touch-sensitive screen, a pressure-or heat-sensitive membrane. In one embodiment, a microphone is an input device for the exemplary client 40. Voice commands may be provided by a user to control operation of the exemplary client 40 when using the microphone to input data to the device.

In one embodiment, the driver controller 29, array driver 22, and display array 30 are appropriate for any of the types of displays described herein. For example, in one embodiment, the driver controller 29 is a conventional display controller or a bi-stable display controller (e.g., an interferometric modulator controller). In another embodiment, the array driver 22 is a conventional driver or a bi-stable display driver (e.g., an interferometric modulator display). In yet another embodiment, the display array 30 is a typical display array or a bi-stable display array (e.g., a display including an array of interferometric modulators).

Power supply 50 is any of a variety of energy storage devices, as is well known in the art, for example, in one embodiment, power supply 50 is a rechargeable battery, such as a nickel-cadmium battery or a lithium ion battery, in another embodiment, power supply 50 is a renewable energy source, capacitor, or solar cell, including a plastic solar cell and solar-cell paint.

In one embodiment, the array driver 22 includes a register that can be set to a predefined value to indicate that the input video stream is in an interlaced format and should be displayed on the bi-stable display in an interlaced format without converting the video stream to a progressive scan format. In this way, the bi-stable display does not require an interlace-progressive scan conversion of interlaced video data.

In some implementations, control programmability resides, as described above, in a display controller that can be located in several places in the electronic display system. In some cases control programmability exists in the array driver 22 at the interface between the electronic display system and the display components themselves. Those skilled in the art will appreciate that the above-described optimization may be implemented in any number of hardware and/or software components and in various configurations.

In one embodiment, the circuitry is embedded in the array driver 22 to take advantage of the fact that: most graphics controllers output a set of signals that include a signal that depicts the addressed horizontal active area of the display array 30. The horizontal active area can be changed by driving register settings in the controller 29. These register settings may be changed by the processor 21. This signal is commonly referred to as a Display Enable (DE) signal. In addition, most display video interfaces utilize a Line Pulse (LP) or a Horizontal Synchronization (HSYNC) signal to indicate the end of a line of data. The circuitry that counts the LPs may determine the vertical position of the current row. A region update function is implemented when the refresh signal is adjusted according to DE and LP counter circuits (signaling vertical regions) from the processor 21 (signaling horizontal regions).

In one embodiment, a driver controller 29 is integrated with the array driver 22. Such embodiments are common in highly integrated systems such as cellular phones, watches, and other small area displays. Dedicated circuitry within such an integrated array driver 22 first determines which pixels, and thus rows, need to be refreshed, and selects only those rows that have pixels that have changed for updating. With such circuitry, particular rows may be addressed in a non-sequential order, varying from view image content to view image content. An advantage of this embodiment is that the data rate between the processor 21 and the display array 30 can be reduced since only video data that has changed needs to be sent over the interface. By reducing the effective data rate required between the processor 21 and the array driver 22, the power consumption, noise immunity, and electromagnetic interference issues of the system may be improved.

Fig. 4 and 5 show one possible actuation protocol for forming a display frame on the 3 x 3 array of fig. 3. FIG. 4B shows a possible set of row and column voltage levels that may be used for pixels having the hysteresis curves of FIG. 4A. In the embodiment of FIGS. 4A/4B, actuating a pixel may include setting the corresponding column to-V_biasAnd sets the corresponding row to + av, which may correspond to-5 volts and +5 volts, respectively. Releasing the pixel may be accomplished by setting the corresponding column to + V_biasAnd sets the corresponding row to the same + av, thereby creating a 0 volt potential difference across the pixel. In those rows where the row voltage is held at 0 volts, the pixels are stable in the state they were originally in, being at + V with the column_biasOr is-V_biasIs irrelevant. Similarly, actuating a pixel can include setting the corresponding column to + V_biasThe corresponding row is set to- Δ V, which may correspond to 5 volts and-5 volts, respectively. Releasing the pixel may be accomplished by setting the corresponding column to-V_biasAnd sets the corresponding row to the same- Δ V, therebyThis is achieved by creating a 0 volt potential difference across the pixel. In those rows where the row voltage is held at 0 volts, the pixels are stable in the state they were originally in, being at + V with the column_biasOr is-V_biasIs irrelevant.

FIG. 5B is a timing diagram showing a series of row and column signals applied to the 3 × 3 array of FIG. 3A, which will result in the display arrangement of FIG. 5A, where actuated pixels are non-reflective. Prior to writing the frame shown in FIG. 5A, the pixels can be in any state, in this example, all the rows are at 0 volts, and all the columns are at +5 volts. Under these applied voltages, all pixels are stable in their existing actuated or released states.

In the frame shown in FIG. 5A, pixels (1, 1), (1, 2), (2, 2), (3, 2) and (3, 3) are activated. To accomplish this, column 1 and column 2 are set to-5 volts, and column 3 is set to +5 volts during the line time for row 1. This does not change the state of any pixels, since all pixels remain within the 3-7 volt stability window. Thereafter, row 1 is strobed with a pulse that rises from 0 volts to 5 volts and then falls back to 0 volts. Thereby actuating the pixels (1, 1) and (1, 2) and releasing the pixels (1, 3). No other pixels in the array are affected. To set row 2 as desired, column 2 is set to-5 volts, and columns 1 and 3 are set to +5 volts. Thereafter, applying the same strobe to row 2 will actuate pixel (2, 2) and release pixels (2, 1) and (2, 3). Again, no other pixels in the array are affected. Similarly, row 3 is set by setting columns 2 and 3 to-5 volts, and column 1 to +5 volts. The row 3 strobe sets the row 3 pixels to the state shown in FIG. 5A. After writing the frame, the row potentials are 0, while the column potentials can remain at either +5 or-5 volts, and the display will thereafter be stable in the arrangement shown in FIG. 5A. It will be appreciated that the same procedure can be used for arrays consisting of tens or hundreds of rows and columns. It will also be appreciated that the timing, sequence, and levels of voltages used to perform row and column actuation can be varied widely within the general principles outlined above, and the above example is exemplary only, and any actuation voltage method can be used.

The detailed structure of interferometric modulators that operate in accordance with the principles set forth above may vary widely. For example, FIGS. 6A-6C show three different embodiments of the moving mirror structure. FIG. 6A is a cross-sectional view of the embodiment of FIG. 2, wherein a strip of reflective material 14 is deposited on orthogonal supports 18. In FIG. 6B, the reflective material 14 is attached to the supports 18 at the corners only, on tethers 32. In FIG. 6C, the reflective material 14 is suspended from a deformable layer 34. This embodiment has several advantages because the structural design and materials used for the reflective material 14 can be optimized with respect to the optical properties, and the structural design and materials used for the deformable layer 34 can be optimized with respect to the desired mechanical properties. The production of various types of interference devices is described in a number of published documents, including, for example, U.S. published application No. 2004/0051929. The above-described structures may be fabricated using a variety of well-known techniques, including a series of material deposition, patterning, and etching steps.

Fig. 7 shows an embodiment of a process flow, which shows a high-level flow chart of a client device 7 control process. The flow chart describes a process used by a client device 7 (e.g. laptop 4, PDA5 or mobile phone 6) connected to a network 3 to graphically display video data received from a server 2 over the network 3. Depending on the embodiment, deletions, additions, and rearrangements of the states in FIG. 7 may be made.

Referring again to fig. 7, beginning at state 74, the client device 7 sends a signal to the server 2 over the network 3 indicating that the client device 7 is ready for video. In one embodiment, a user may begin the process shown in FIG. 7 by turning on an electronic device, such as a mobile phone. Then proceeding to state 76, the client device 7 initiates its control process. An example of initiating a control process is discussed further below with reference to FIG. 8.

Fig. 8 shows an embodiment of a process flow showing a flow chart of a client device 7 control process for starting and running a control process. The flow chart shows state 76 described with reference to fig. 7 in more detail. Depending on the embodiment, deletions, additions, and rearrangements of the states in FIG. 8 may be made.

Beginning at decision state 84, the client device 7 determines whether activity at the client device 7 requires launching an application at the client device 7, or whether the server 2 has transmitted an application to the client device 7 for execution, or whether the server 2 has transmitted a request to the client device 7 to execute an application resident at the client device 7. if an application does not require launching, the client device 7 remains in decision state 84. after launching an application, proceeding to state 86, the client device 7 initiates a process for the client device to receive and display video data that can be streamed from the server 2 or downloaded to memory of the client device 7 for later access And may be interlaced or progressive scanned video data, and have a variety of different refresh rates, display array 30 may be partitioned into regions of arbitrary shape and size, where each region receives video data having characteristics specific to only that region (e.g., refresh rate or compression encoding), these regions may change the video data characteristics and shape and size, these regions may be opened and closed and may be reopened, along with the video data, the client device 7 may also receive control data, which may include commands sent from the server 2 to the client device 7 regarding, for example, the characteristics of the video data (e.g., compression encoding, refresh rate, and interlaced or progressive scan video data). the control data may include control instructions for partitioning the display array 30, as well as different instructions for different regions of the display array 30.

In an exemplary embodiment, the server 2 sends control data and video data to a PDA via a wireless network 3 to generate a continuously updated clock in the upper right corner of the display array 30, a picture in the form of a slide show in the upper left corner of the display array 30, periodically updated scores for a game along the lower region of the display array 30, and a cloud bubble reminder mark that continuously scrolls across the display array 30 to remind of purchasing bread. The video data corresponding to the photos displayed in slide show form, after download, resides in the PDA memory and is in an interlaced format. The clock and ball game video data is streamed text from the server 2. The reminder indicia is text with graphics in a progressive scan format. It should be understood that what is shown here is merely an exemplary embodiment. Other embodiments are possible and are encompassed by state 86 and still fall within the scope of the present description.

Proceeding to decision state 88, the client device 7 looks for a command from the server 2, such as a command to reposition an area of the display array 30, a command to change the refresh rate of an area of the display array 30, or an exit command. Upon receiving a command from the server 2, the client device 7 proceeds to decision state 90 and determines whether the command received while in decision state 88 is an exit command. If, while in decision state 90, it is determined that the command received while in decision state 88 was an exit command, the client device 7 proceeds to state 98 to stop executing the application and reset. The client device 7 may also transmit status or other information to the server 2 and/or may receive such similar communications from the server 2. If, while in decision state 90, it is determined that the command received from the server 2 while in decision state 88 was not an exit command, the client device 7 returns to state 86. If no command is received from the server 2 while in the decision state 88, the client device 7 proceeds to a decision state 92 where the client device 7 looks for a command from the user, such as a command to stop updating an area of the display array 30, or an exit command, in the decision state 92. If, while in decision state 92, the client device 7 does not receive a command from the user, the client device 7 returns to decision state 88. If a command is received from the user while in decision state 92, the client device 7 proceeds to decision state 94 where the client device 7 determines whether the command received in decision state 92 is an exit command in decision state 94. If, while in decision state 94, the command received from the user while in decision state 92 is not an exit command, then the client device 7 proceeds from decision state 94 to state 96. At state 96, the client device 7 sends the user command received while in state 92, e.g., a command to stop updating an area of the display array 30, to the server 2, after which it returns to the decision state 88. If, while in decision state 94, it is determined that the command received from the user while in decision state 92 was an exit command, the client device 7 proceeds to state 98 and stops executing the application. The client device 7 may also transmit status or other information to the server 2 and/or may receive such similar communications from the server 2.

Fig. 9 shows a control procedure used by the server 2 to send video data to the client device 7. The server 2 sends control information and video data to the client device 7 for display. Depending on the embodiment, the states in FIG. 9 may be deleted, added, or rearranged.

Starting from state 124, the server 2 waits in embodiment (1) for a data request from the client device 7 over the network 3, or in embodiment (2) the server 2 sends video data without waiting for a data request from the client device 7 both embodiments cover situations where either the server 2 or the client device 7 can initiate a request to have video data sent from the server 2 to the client device 7.

The server 2 proceeds to a decision state 128 in which it is determined whether a response (ready indication signal) has been received from the client device 7 indicating that the client device 7 is ready from the client device 7. If the ready indication signal is not received while in state 128, the server 2 remains in decision state 128 until a ready indication signal is received.

Upon receiving the ready indication signal, the server 2 proceeds to a state 126, and in the state 126, the server 2 transmits control data to the client device 7. The control data may be streamed from the server 2 or may be downloaded to the memory of the client device 7 for later access. The control data may partition the display array 30 into regions of arbitrary shape and size, and may define video data characteristics, such as refresh rate or interlaced format, for a particular region or for all regions. The control data may cause these areas to be turned on or off or turned back on.

Proceeding to state 130, the server 2 sends video data. The video data may be streamed from the server 2 or may be downloaded to the memory of the client device 7 for later access. The video data may include moving images, or still images, text, or picture images. The video data may also have various compression encoding approaches, and may be interlaced or progressively scanned video data, and have various different refresh rates. Each region may receive video data having characteristics (e.g., refresh rate or compression coding) that are unique to that region only.

The server 2 proceeds to a decision state 132 where in the decision state 132 the server 2 looks for a command from the user, such as a command to stop updating an area of the display array 30, a command to increase the refresh rate, or an exit command. If, while in decision state 132, server 2 receives a command from the user, server 2 proceeds to state 134. At state 134, the server 2 executes the command received from the user in state 132, and then proceeds to decision state 138. If, while in decision state 132, server 2 does not receive a command from the user, server 2 proceeds to decision state 138.

In state 138, the server 2 determines whether the client device 7 needs to take action, such as taking action to receive and store video data for subsequent display, increasing the data transmission rate, or expecting the next set of video data to be in an interleaved format. If, while in decision state 138, the server 2 determines that a measure needs to be taken by the client, the server 2 proceeds to state 140, in state 140 the server 2 sends a command to the client device 7 to take the measure, after which the server 2 proceeds to state 130. If, while in decision state 138, server 2 determines that no action is required from the client, server 2 proceeds to decision state 142.

Proceeding to decision state 142, server 2 determines whether to end the data transfer. If in decision state 142 server 2 decides not to end the data transfer, server 2 returns to state 130. If, while in decision state 142, server 2 decides to end the data transfer, server 2 proceeds to state 144 where server 2 ends the data transfer and sends an exit message to the client in state 144. The server 2 may also transmit status information or other information to the client device 7 and/or may receive such similar communications from the client device 7.

Since bi-stable displays, as is typical with most flat panel displays, consume most of their power during a frame update, it is desirable to be able to control the frequency of updating the bi-stable display in order to conserve power. For example, if the change between adjacent frames of a video stream is very small, the display array may be updated less frequently with little or no loss in image quality. As an example, in a typical PC desktop application, the quality of the image displayed on an interferometric modulator display will not be degraded by the reduced refresh rate, because interferometric modulator displays are less prone to flicker caused by reduced refresh rates as most other displays. Thus, in operation for certain applications, a PC display system may reduce the refresh rate of a bi-stable display element, such as an interferometric modulator, with very little effect on the output of the display.

FIG. 10 shows, in plan view as seen by an observer, one embodiment of an interferometric modulator display 200 in which the interferometric modulator display 200 has been divided into a first region 202, a second region 204, and a third region 206. In these embodiments, different regions in the interferometric modulator display 200, such as the first region 202, the second region 204, and the third region 206, may be treated in a separate, different manner with respect to updating the images displayed in the different regions 202, 204, 206 depending on the nature of the images displayed in the respective regions 202, 204, 206.

For example, in one embodiment, the first column 202 may display a toolbar having a plurality of icons corresponding to different operating capabilities that may be provided by a device that includes the interferometric modulator display 200. It should be understood after considering the description of the various embodiments that the interferometric modulator display 200 may be incorporated into a wide variety of electronic devices, including, but not limited to, cellular telephones, Personal Digital Assistants (PDAs), text messaging devices, calculators, portable measurement or medical devices, video players, personal computers, and the like. Thus, in one embodiment, the first region 202 may depict an image corresponding to a toolbar having a plurality of icons that maintain a constant configuration and position relative to the interferometric modulator display 200 during use, except for the coloration or conspicuity of a particular icon in the first region 202 as the corresponding function is selected. Thus, the image displayed in the first region 202 of the interferometric modulator display 200 will typically need to be updated relatively infrequently or not updated in certain specific applications.

A second region 204 may correspond to an area of the interferometric modulator display 200 where a displayed image has upgrade requirements that are significantly different from the image presented in the first region 202. For example, the second region 204 may correspond to a series of video images presented on the interferometric modulator display 200 that exhibit a higher update rate (e.g., an update rate of about 15Hz corresponding to a video stream). Thus, the update requirements for the image depicted in the first region 202 may be of a non-periodic nature that is infrequent, such as not substantially updated during use if the image is constant, or relatively infrequently non-periodic when, for example, a user selects an icon to activate the corresponding operating capability of a device that includes the interferometric modulator display 200. However, the update requirement for the image in the second region 204 will generally be of a periodic nature, corresponding to the periodic framing of video data displayed in the second region 204. However, updates to the image displayed in the second region 204 can be readily implemented in an unsynchronized manner relative to the updates provided for the image in the first region 202. Furthermore, in some embodiments, the regions may overlap, i.e., designate an overlapping portion where one region is located on top of another region and covers the underlying region, such that an interferometric modulator may be included in two or more regions. For example, when the display 200 is divided into a first region and a second region, a first plurality of interferometric modulators may correspond to the first region and a second plurality of interferometric modulators may correspond to the second region, one or more interferometric modulators of the first plurality of interferometric modulators may also be an interferometric modulator of the second plurality of interferometric modulators. In such an embodiment, interferometric modulators included in both regions are refreshed with the first plurality of interferometric modulators during a first refresh cycle and with the second plurality of interferometric modulators during a second refresh cycle. One or more of the zones may be divided into any shape, such as square, circular, or polygonal.

The update requirements of the image displayed in the third region 206 may in turn differ from the update requirements of the first region 202 or the second region 204. For example, in one embodiment, the data displayed in the third region 206 may comprise text, such as e-mail or news content, that may be periodically scrolled through by the reader/user of the device, which may indicate a corresponding frequent update period of the images in the third region 206. However, when the user reads the displayed information, the third region 206 will typically take a long period at a relatively constant image, thus presenting a period of no updates. Thus, the interferometric modulator display 200 may support update characteristics that vary significantly over time, such as periods of substantially no update when the displayed image is static and relatively high rates of update periods when the image varies. It should also be appreciated that the image displayed in the third region 206 may also be updated in an asynchronous manner with respect to the updating of the data in the first region 202 and the second region 204.

In some embodiments, in addition to different update rates, the interferometric modulator display 200 may provide different update schemes that may also reduce power consumption. For example, the first region 202 may be updated in a manner similar to a progressive scan type drive scheme. The second region 204 may be driven by a waveform similar to that used by the first region 202, however, instead of writing to each row during each refresh cycle, every other row may be written in an interleaved manner. In another embodiment, the third region 206 may be pixel-by-pixel updated, e.g., only pixels in the image that have changed are updated and other pixels are not refreshed or updated, thereby limiting the updates to those pixels that change state. This embodiment may be advantageously used when sequential data frames exhibit a relatively high frame-to-frame association.

FIG. 11 is a high level flow chart of one embodiment in which such a system may take advantage of the operating characteristics provided by the interferometric modulator display 200. It should be noted that the process shown in FIG. 11 includes state 86 in the process described in FIG. 8. In the process shown, a client device 7 receives video data content from a server 2, defines regions within the interferometric modulator display 200 such that a portion of the data will be displayed on a corresponding region, sets or associates a refresh rate with each region according to the data or some other predetermined criteria, and displays the video data on the corresponding region in the display 200. Depending on the embodiment, additional states may be added, other states deleted, and the order of the states rearranged.

The process 300 begins receiving data from the server 2 upon the occurrence of a triggering event of the client device 7. The triggering event may be initiated by the user, by a signal directly or indirectly from the server, or by the client device 7. In process 300, client device 7 connects to server 2 in state 304. While connected to the server 2, there may be information interaction directly between the client device 7 and the server 2, which may include identifying information about the client device 7 (including the display functionality of the client device 7). After the client device 7 connects with the server 2, the process 300 continues to state 306, where the client device 7 checks whether it receives the partition information and the refresh rate information in state 306. If it has not, the process 300 continues to state 332 where it receives a delay in state 322 and then loops back to state 306.

If the client device 7 receives the partition and refresh rate information, the process 300 proceeds to state 308 and the display 200 is partitioned according to the partition data. It will be appreciated that the division of the data into one or more display areas may be done locally at the client device or remotely, for example by the server 2. Communication between the server 2 and the client device 7, including receiving server commands at the client device 7 and sending commands received at the client device (e.g., from a user), may be controlled as shown in fig. 8. It will also be appreciated that the partitioning in state 308 may be performed dynamically in a time-varying manner, such that, for example, during certain periods, data transmitted between the server 2 and client devices 7 over the network 3 is displayed in an un-partitioned manner (e.g., in a single display area), while in other periods it is divided into a plurality of different display areas for display, depending on the nature of the data transmitted at any given time.

Process 300 then continues to state 310 to set a refresh rate for each partition. Process 300 then continues to state 312 where a signal is sent to server 2 indicating that it is ready to receive video data in state 312. The server 2 transmits video data to the client device 7 in response to receiving the readiness signal of the client device 7. Process 300 then continues to state 314 where video data is received by client device 7 from server 2. Processing of the received video data is shown in fig. 12 with reference to the starting point at "C" in state 314.

Process 300 continues to state 316 and checks whether client device 7 receives a signal indicating that it has been released from server 2. If it does receive a release signal, process 300 continues to state 318 where it ends its session with the server 2 and sets default parameters as needed in state 318. If a release signal is not received, the process 300 continues to state 320 where it experiences a delay and then returns to state 306.

FIG. 12 is a high level flow chart of one embodiment of a process 400 for dividing a display into one or more viewing zones and updating each of the one or more viewing zones at a corresponding appropriate update rate FIG. 12 shows some of the states that occur in one embodiment in accordance with state 314 in FIG. 11.

Process 400 begins at state 402 where client device 7 receives video data in state 402. Process 400 then proceeds to state 404 and identifies video data to be displayed in the two or more partitioned regions of the display. Following the division in state 404, video content is displayed on the interferometric modulator display 200 of the client device 7 in state 406, with the divided video data displayed on a corresponding divided region of the display 200, and each of the one or more regions may be updated at an associated refresh rate. The refresh rate may be set using information received from the server 2 or may be set and dynamically changed according to the content of the video data, for example according to whether the change in the displayed image is fast or slow, or according to user input. In one embodiment, the server 2 specifies the location, size, geometry, and refresh rate of each region. In addition, the server 2 can identify video data to be displayed in a specific area among the video data transmitted to the client device 7.

These embodiments efficiently utilize available resources while maintaining high quality images displayed on the interferometric modulator display 200. For example, in one embodiment, the server 2 may provide text files to the client device 7 over the network 3. Upon receiving the text file, the client device 7 may divide the text data in one or more regions 202, 204, 206 of the display 200. However, once the data is displayed on the interferometric modulator device 200, no further updates are required until the video data displayed in the one or more partitions 202, 204, 206 changes. If the text file data comprises a relatively brief email message, the entire email message may be displayed in the one or more regions of the interferometric modulator display 200 and neither the server 2 nor the client device 7 need refresh the image before the displayed image changes, such as by the user scrolling through a larger range of email messages, switching operating modes of the client device 7, or other situations indicating a change in the displayed information. This provides significant advantages: the available battery and processing capacity at the client device 7 is not significantly consumed simply by maintaining a static image displayed in the interferometric modulator display 200.

Likewise, by taking advantage of the characteristics provided by the interferometric modulator display 200, the available processing and transmission bandwidth capacity of the server 2 may be more efficiently utilized. For example, in certain embodiments, the server 2 has been formed to communicate with a client device 7 having an interferometric modulator display 200 over the network 3. Thus, the partitioning of the displayed data in state 404 may be performed on server 2 (also referred to as the "head end" in some applications). Thus, the server 2 may provide data to the client devices 7 in a partitioned manner that may be dynamically adjusted according to the needs of each of a large number of client devices 7. For example, data provided by the server 2 may be provided to one client device 7 at a first, relatively low, or even substantially zero, update rate over certain time periods, thereby conserving bandwidth and processing capacity of the server 2 to provide data to other client devices over other links at a second, higher update rate corresponding to different requirements of the data provided to the other client devices.

Embodiments provide unique operating characteristics of an interferometric modulator display 200, providing the ability to divide a display into one or more zones 202, 204, 206, each having its own prescribed refresh rate, one or more of which may be substantially zero rate, e.g., not updated for at least a limited period of time, yet another embodiment comprises a dynamic data display system comprising a server 2 in communication with one or more client devices 7, wherein characteristics of each client device 7 are communicated to the server 2, and wherein data provided to each client device 7 is formatted differently depending on characteristics of each client device, e.g., the refresh rate may depend on the type of data being displayed. Array driver 22 may be programmed to skip refreshes available to display array 30. in one embodiment, a register in array driver 22 stores a value representing a skip frame count value, such as 0, 1, 2, 3, 4, etc. thus, array driver 22 may access the register to determine the frequency of refreshing display array 30. for example, values of 0, 1, 2, 3, 4, and 5 may represent an update of the driver once per frame, every other frame, every third frame, every fourth frame, every fifth frame, and every sixth frame, respectively.

FIG. 13 shows one embodiment of a display 500. The display 500 of FIG. 13 can be manufactured in a variety of shapes and sizes. In one embodiment, the display 500 is generally rectangular, although in other embodiments the display is square, hexagonal, octagonal, circular, triangular, or other symmetrical or asymmetrical shapes. The display 500 can be fabricated in a variety of sizes. In one embodiment, one side of the display 500 is less than about 0.5 inches, about 1 inch, about 10 inches, about 100 inches, or greater than 100 inches long. In one embodiment, the length of one side of display 500 is between about 0.5 inches and 3.5 inches long.

Depending on the content to be displayed in the display, the display 500 may be divided into partitions 502 and 504. By partitioning the display, different display partitions can display different content and can be refreshed or updated at different rates. For example, only those partitions of display 500 that need to be updated or refreshed may be updated or refreshed. Referring to FIG. 13, the image displayed by the first partition 502 does not need to be updated or refreshed as frequently as the second partition 504. For example, the first partition 502 displays a still image (as shown), while the second partition 504 displays a stock quote bar (as shown), animation, or clock.

In one embodiment, a display 500 includes two sections, although in other embodiments, the display 500 includes more than two sections. For example, the display 500 may include three, four, eight, 32, or 256 partitions. In one embodiment, display 500 includes a partition with a relatively low refresh rate and a partition with a relatively high refresh rate. The relative size and position of the various sections of display 500 may be fixed or variable, depending on the content to be displayed on display 500. In one embodiment, the ratio of the surface area of the first partition 502 to the second partition 504 is about 90: 10, about 75: 25, about 50: 50, about 25: 75, or about 10: 90.

In one embodiment, the client device 7 receives control commands or information from the server 2 (not shown) that determine the manner in which the display 500 partitions itself and the rate at which the contents of each partition are updated or refreshed.

FIG. 14 shows an example of information or commands provided by a server to implement the partitioning of the display 500. A server-provided message 600 may include one or more of the following: an identification segment 602, a server control request 604, a partition command 606, a first partition refresh rate value 608, a second partition refresh rate value 610, hop count value information 612, format type 614, and node information 616.

In one embodiment, identification segment 602 identifies the type of content being sent to client device 7 (not shown). The phone number of the calling party may be provided, for example, if the content is a phone call.if the content is from a web site, an identification of the web site may be provided by identification segment 602. Server control request 604 is a request from a server requesting the client to permit the server to control its display and refresh rate and/or update rate In some embodiments, the server message 600 also includes skip count value information 612, video data format type 614, and/or other information such as node information 616. As described above, skip count value information 612 may be used to determine whether a frame of video data is to be displayed. video data format type 614 may be used by the server 2 to indicate to the client device 7 what type of data is being sent from the server 2. node information 616 in this information may be used to indicate to the client device 7 node or network device information related to data being sent from the server 2.

It should be noted that and as will also be discussed in the embodiments below, the partition update and refresh rates specified in the server messages, or determined according to local criteria within the client device 7, are not limited to specific, set numerical values. The update and refresh "rates" may be based on data set satisfaction criteria, triggering events, interrupts, user interactions, and other incentives. This situation may cause refresh and update events that vary, depend on the situation, and are not synchronous.

FIGS. 15A and 15B are block diagrams illustrating a system of an embodiment of a display device 2040. The display device 2040 can be, for example, a cellular or mobile telephone. However, the same components of display device 2040 and slight variations thereof are also illustrative of various types of display devices such as televisions and portable media players.

The display device 2040 includes a housing 2041, a display 2030, an antenna 2043, a speaker 2045, an input device 2048, and a microphone 2046. The housing 2041 is typically made by any of a number of manufacturing processes well known to those skilled in the art, including injection molding and vacuum forming. Further, the housing 2041 may be made from any of a wide variety of materials, including but not limited to plastic, metal, glass, rubber, and ceramic, or a combination thereof. In one embodiment, the housing 2041 includes removable portions (not shown) that can be interchanged with other removable portions of different color, or containing different logos, pictures, or symbols.

The display 2030 of exemplary display device 2040 may be any of a wide variety of displays, including a bi-stable display as described herein. In other embodiments, the display 2030 comprises a flat panel display, such as a plasma, EL, OLED, STN LCD, or TFT LCD as described above, or a non-flat panel display, such as a CRT or other tube device, as is well known to those skilled in the art. However, for purposes of describing the present embodiment, the display 2030 includes an interferometric modulator display, as described herein.

FIG. 15B schematically shows components in an embodiment of an exemplary display device 2040. The exemplary display device 2040 shown includes a housing 2041 and may include other components at least partially enclosed therein. For example, in one embodiment, the exemplary display device 2040 includes a network interface 2027, the network interface 2027 including an antenna 2043 coupled to a transceiver 2047. The transceiver 2047 is connected to the processor 2021, which processor 2021 is in turn connected to conditioning hardware 2052. Conditioning hardware 2052 may be configured to condition (e.g., filter) a signal. Conditioning hardware 2052 is coupled to a speaker 2045 and a microphone 2046. The processor 2021 is also connected to an input device 2048 and a driver controller 2029. The driver controller 2029 is coupled to a frame buffer 2028 and to the array driver 2022, which in turn is coupled to a display array 2030. A power supply 2050 provides power to all components as required by the design of the particular exemplary display device 2040.

The network interface 2027 includes the antenna 2043 and the transceiver 2047 so that the exemplary display device 2040 can communicate with one or more devices over a network. In one embodiment, the network interface 2027 may also have some processing functions to reduce the requirements on the processor 2021. The antenna 2043 is any antenna known to those skilled in the art for transmitting and receiving signals. In one embodiment, the antenna transmits and receives RF signals according to the IEEE802.11 standard, including IEEE802.11 (a), (b), or (g). In another embodiment, the antenna transmits and receives RF signals according to the Bluetooth (BLUETOOTH) standard. In the case of a cellular telephone, the antenna is designed to receive CDMA, GSM, AMPS or other conventional signals used to communicate in a wireless mobile telephone network. The transceiver 2047 pre-processes the signals received from the antenna 2043 so that they may be received by and further processed by the processor 2021. The transceiver 2047 also processes signals received from the processor 2021 so that they may be transmitted from the exemplary display device 2040 via the antenna 2043.

In an alternative embodiment, the transceiver 2047 may be replaced by a receiver, in yet another alternative embodiment, the network interface 2027 may be replaced by an image source, which may store or generate image data to be sent to the processor 2021.

The processor 2021 generally controls the overall operation of the exemplary display device 2040. The processor 2021 receives data, such as compressed image data, from the network interface 2027 or an image source and processes the data into raw image data or into a format that is readily processed into raw image data. The processor 2021 then sends the processed data to the driver controller 2029 or to frame buffer 2028 for storage. Raw data generally refers to information that can identify the image characteristics at each location within an image. For example, the image characteristics may include color, saturation, and gray-scale level.

In one embodiment, the processor 2021 includes a microcontroller, CPU, or logic unit to control operation of the exemplary display device 2040. Conditioning hardware 2052 typically includes amplifiers and filters for sending signals to the speaker 2045, and for receiving signals from the microphone 2046. Conditioning hardware 2052 may be discrete components within the exemplary display device 2040 or may be incorporated within the processor 2021 or other components.

The driver controller 2029 receives raw image data generated by the processor 2021 either directly from the processor 2021 or from the frame buffer 2028 and reformats the raw image data appropriately for high speed transmission to the array driver 2022. In particular, the driver controller 2029 reformats the raw image data into a data flow having a raster-like format, such that it has a time order suitable for scanning the display array 2030. The driver controller 2029 then sends the formatted information to the array driver 2022. Although a driver controller 2029, such as an LCD controller, is typically associated with the system processor 2021 as a stand-alone Integrated Circuit (IC), such controllers may be implemented in a number of ways. They may be embedded in the processor 2021 as hardware, embedded in the processor 2021 as software, or fully integrated in hardware with the array driver 2022.

Typically, the array driver 2022 receives the formatted information from the driver controller 2029 and reformats the video data into a parallel set of waveforms that are applied many times per second to the hundreds and sometimes thousands of leads coming from the display's x-y array of pixels.

In one embodiment, the driver controller 2029, array driver 2022, and display array 2030 are appropriate for any of the types of displays described herein. For example, in one embodiment, the driver controller 2029 is a conventional display controller or a bi-stable display controller (e.g., an interferometric modulator controller). In another embodiment, the array driver 2022 is a conventional driver or a bi-stable display driver (e.g., an interferometric modulator display). In one embodiment, a driver controller 2029 is integrated with the array driver 2022. Such embodiments are common in highly integrated systems such as cellular phones, watches, and other small area displays. In yet another embodiment, the display array 2030 is a typical display array or a bi-stable display array (e.g., a display including an array of interferometric modulators). The input device 2048 enables a user to control the operation of the exemplary display device 2040. In one embodiment, input device 2048 includes a keypad (e.g., a QWERTY keyboard or a telephone keypad), a button, a switch, a touch-sensitive screen, a pressure-or heat-sensitive membrane. In one embodiment, the microphone 2046 is an input device for the exemplary display device 2040. When the microphone 2046 is used to input data to the device, voice commands may be provided by a user to control operation of the exemplary display device 2040.

The power supply 2050 may include a variety of energy storage devices, as are well known in the art. For example, in one embodiment, power supply 2050 is a rechargeable battery, such as a nickel-cadmium battery or a lithium ion battery. In another embodiment, power supply 2050 is a renewable energy source, a capacitor, or a solar cell, including plastic solar cells and solar-cell paint. In another embodiment, power supply 2050 is configured to receive power from a wall outlet.

In some implementations control programmability resides, as described above, in a driver controller, which can be located in several places in the electronic display system.

While the above detailed description has shown, described, and pointed out novel features as applied to various embodiments, it will be understood that various omissions, substitutions, and changes in the form and details of the device or process illustrated may be made by those skilled in the art without departing from the spirit of the invention. It will be recognized that the present invention may be embodied within a form that does not provide all of the features and benefits set forth herein, as some features may be used or practiced separately from others.

Claims (65)

1. A display system, comprising:

at least one driving circuit configured to provide signals for displaying video data; and

a display comprising an array of a plurality of bi-stable display elements, the array configured to display video data using signals received from the drive circuit, and the plurality of bi-stable display elements comprising interferometric modulators,

wherein the array is divided into two or more regions, each region comprising at least one bi-stable display element, and wherein the drive circuit is configured to refresh each of the two or more regions according to a refresh rate associated with each region, an

Wherein the two or more regions comprise a first region comprising a first set of interferometric modulators and a second region comprising a second set of interferometric modulators.

2. The display system of claim 1 wherein the bi-stable display element is an interferometric modulator comprising two reflective layers movable relative to each other and separated by a space defining an interferometric cavity.

3. The display system of claim 1, wherein the bi-stable display element is configured to maintain a selected optical state without refreshing.

4. The display system of claim 1, wherein the display is configured to continuously display an image without refresh.

5. The display system of claim 1, wherein the drive circuit is further configured to refresh at least one of the zones at a rate proportional to a frame data rate.

6. The display system of claim 1, wherein the drive circuit is further configured to refresh at least one of the regions according to only a frame data rate.

7. The display system of claim 1, wherein a refresh rate of at least one of the zones is substantially zero.

8. The display system of claim 1, wherein the drive circuit is further configured to receive frame data and refresh one or more regions only when the frame data is received.

9. The display system of claim 1, wherein the drive circuit is configured to divide the array.

10. The display system of claim 1, further comprising an input device configured to receive a user selection, wherein the drive circuit is configured to divide the array according to the user selection.

11. The display system of claim 1, further comprising:

a server in communication with the display system,

wherein the drive circuitry is configured to divide the array according to instructions from the server.

12. The display system of claim 1, wherein the drive circuit is configured to receive at least a portion of the video data from a server in communication with the display system.

13. The display system of claim 1, wherein the driver circuit is configured to receive at least a portion of the video data from a program running on the display system.

14. The display system of claim 1, wherein the first set of interferometric modulators refresh at a first refresh rate and the second set of interferometric modulators refresh at a second refresh rate.

15. The display system of claim 1, wherein at least one interferometric modulator of the first set of interferometric modulators is also an interferometric modulator of the second set of interferometric modulators.

16. The display system of claim 1, wherein the first set of interferometric modulators are arranged in a polygonal shape.

17. The display system of claim 15, wherein the at least one interferometric modulator is refreshed with the first set of interferometric modulators during a first refresh cycle, and the at least one interferometric modulator is refreshed with the second set of interferometric modulators during a second refresh cycle.

18. The display system of claim 14, wherein the second refresh rate is different from the first refresh rate.

19. The display system of claim 14, wherein the second refresh rate is the same as the first refresh rate, and a start time of a refresh of the first region is different from a start time of the refresh of the second region.

20. The display system of claim 14, wherein the first refresh rate is determined based at least in part on a frame rate of the data displayed in the first region.

21. The display system of claim 14, wherein the first refresh rate is predetermined.

22. The display system of claim 14, wherein the first refresh rate varies over time.

23. The display system of claim 1, further comprising:

a processor in electrical communication with the display, the processor configured to process image data.

24. The display system of claim 1, further comprising:

a controller configured to send at least a portion of the image data to the at least one driver circuit.

25. The display system of claim 23, further comprising:

an image source module configured to send the image data to the processor.

26. The display system of claim 25, wherein said image source module comprises a transceiver.

27. The display system of claim 23, further comprising:

an input device configured to receive input data and to communicate the input data to the processor.

28. A method of displaying data on a bi-stable display of a device, the method comprising:

dividing the bi-stable display of the device into two or more regions, wherein the two or more regions comprise a first region comprising a first set of interferometric modulators and a second region comprising a second set of interferometric modulators;

displaying video data on the two or more regions; and

each of the two or more regions is refreshed according to a refresh rate associated with each of the two or more regions.

29. The method of claim 28, wherein the bi-stable display comprises an array of interferometric modulators.

30. The method of claim 28, further comprising receiving at least a portion of the video data at the device from a server.

31. The method of claim 28, further comprising updating two or more regions using one or more update schemes.

32. The method of claim 28, wherein refreshing at least one of the two or more zones comprises using a refresh rate that is based on a frame rate of the data being displayed.

33. The method of claim 31, wherein at least one of the one or more update schemes is selected using a procedure associated with the received data.

34. The method of claim 28, further comprising receiving display information indicative of a characteristic of the display and using the display information to select an update scheme.

35. A communication system for server-based control of a bi-stable display on a client device, comprising:

a client device comprising the bi-stable display having a plurality of bi-stable display elements, the client device configured to transmit display information over a communication network,

wherein two or more regions of the bi-stable display are defined by a server, each region including interferometric modulators having an associated refresh rate, and the server is further configured to transmit video data to the client device over the communication network according to the display information,

wherein the client device is further configured to receive video data from the server, display the video data on the two or more regions of the display, and update each region using the associated refresh information.

36. The communication system of claim 35, wherein the display information indicates two or more characteristics of the display.

37. The communication system of claim 35, wherein the display information indicates a display mode.

38. The communication system of claim 35, wherein the display information includes information indicating where the video data should be rendered on the bi-stable display.

39. The communication system of claim 35, wherein the server is further configured to identify video data to be displayed in each of the two or more zones.

40. The communication system of claim 35, further comprising:

a processor in electrical communication with the display, the processor configured to process image data.

41. The communication system of claim 40, further comprising:

a driving circuit configured to send at least one signal to the display.

42. The communication system of claim 41, further comprising:

a controller configured to send at least a portion of the image data to the drive circuit.

43. The communication system of claim 40, further comprising:

an image source module configured to send the image data to the processor.

44. The communication system as recited in claim 43, wherein the image source module comprises a transceiver.

45. The communication system of claim 40, further comprising:

an input device configured to receive input data and to communicate the input data to the processor.

46. A data display system, comprising:

a client device in data communication with a content server configured to provide video data, the client device comprising a bi-stable display configurable to display data in two or more regions, each region associated with at least one bi-stable display element,

wherein each region of the bi-stable display is refreshed at its own refresh rate,

wherein the two or more regions include a first region and a second region, and wherein the bi-stable display includes a first set of interferometric modulators and a second set of interferometric modulators, the first set of interferometric modulators being associated with the first region and the second set of interferometric modulators being associated with the second region.

47. The data display system of claim 46, wherein at least one of the zones is individually addressable by the content server.

48. The data display system of claim 46, wherein the content server includes a processor and a software module, the software module being associated with the provided data.

49. The data display system of claim 46, wherein the client device is configured to communicate characteristics of the display to the content server.

50. The data display system of claim 46, wherein at least one interferometric modulator from the first set of interferometric modulators is assigned to the first set of interferometric modulators and the second set of interferometric modulators.

51. A method of manufacturing a display system, comprising:

coupling at least one drive circuit configured to provide signals for displaying video data to a display, the display comprising an array of a plurality of bi-stable display elements;

configuring the array to display video data using signals received from the drive circuitry and divided into two or more regions, the two or more regions including a first region comprising at least a first interferometric modulator and a second region comprising at least a second interferometric modulator; and

the drive circuit is configured to refresh each of the two or more regions according to a refresh rate associated with each region.

52. The method of claim 51 wherein the bi-stable display element is an interferometric modulator comprising two reflective layers movable relative to each other and separated by a space defining an interferometric cavity.

53. The method of claim 51, wherein the bi-stable display element is configured to maintain a selected optical state without refreshing.

54. The method of claim 51, wherein the drive circuit is further configured to refresh at least one of the zones according to only a frame data rate.

55. A display system made by a process, the process comprising:

coupling at least one drive circuit configured to provide signals for displaying video data to a display, the display comprising an array of a plurality of bi-stable display elements;

configuring the array to display video data using signals received from the drive circuitry and divided into two or more regions, the two or more regions including a first region comprising at least a first interferometric modulator and a second region comprising at least a second interferometric modulator; and

the drive circuit is configured to refresh each of the two or more regions according to a refresh rate associated with each region.

56. The display system of claim 55 wherein the bi-stable display element is an interferometric modulator comprising two reflective layers movable relative to each other and separated by a space defining an interferometric cavity.

57. The display system of claim 55, wherein the bi-stable display element is configured to maintain a selected optical state without refreshing.

58. The display system of claim 55, wherein the drive circuit is further configured to refresh at least one of the regions according to only a frame data rate.

59. A display system, comprising:

means for providing an image data signal;

means for dividing a display array comprising a plurality of bi-stable display elements into two or more regions, the two or more regions comprising a first region comprising at least a first interferometric modulator and a second region comprising at least a second interferometric modulator; and

means for displaying the image using the image data signal, wherein each region of the two or more regions is refreshed according to a refresh rate associated with each region.

60. A display system according to claim 59, wherein the providing means comprises at least one drive circuit configured to provide a signal for displaying video data.

61. A display system according to claim 59 wherein the display member comprises an array of a plurality of bistable elements.

62. The display system of claim 59 wherein the bi-stable display element is an interferometric modulator comprising two reflective layers movable relative to each other and separated by a space defining an interferometric cavity.

63. The display system of claim 59 wherein the bi-stable display element is configured to maintain a selected optical state without refresh.

64. The display system of claim 59, wherein the providing means is configured to refresh at least one of the regions according to only a frame data rate.

65. A display system as in claim 59, wherein the dividing means comprises a drive circuit.