MXPA05009166A - System and method for addressing a mems display - Google Patents

Abstract

A system and method for addressing an array of MEMS display elements, such as interferometric modulators, from a drive control. A display includes groups of display elements that are addressed with a commonly applied drive signal. In one embodiment, the groups of display elements are configured to have different response times and are driven by pulses of varying length indicative of those response times. In another embodiment, the groups of display elements are configured to have different actuation voltages and are driven by pulses of varying voltage indicative of those actuation voltages.

Description

SYSTEM AND METHOD FOR DIRECTING A MEMS DISPLAY SCREEN BACKGROUND 'Field The field of the invention relates to microelectronic-mechanical systems (MEMS).

Description of Related Technology Microelectromechanical systems (MEMS) include micromechanical elements, actuators, and electronic devices. Micromechanical elements can be created using deposition, etching and / or other micro-machining processes that etch parts of substrates and / or layers of deposited material or add layers to form electrical and electromechanical devices. One type of MEMS device is the so-called interferometric modulator. An interferometric modulator may comprise a pair of conductive plates, one or both of which may be partially transparent and capable of relatively moving after the application of an appropriate electrical signal. One plate may comprise a stationary layer deposited on a substrate, the other plate may comprise a metal membrane suspended on the stationary layer. These devices have a wide range of applications, and it would be beneficial in the art to use and / or modify the characteristics of those types of devices so that their characteristics can be exploited to improve existing products and create new products that have not yet been developed.

SUMMARY The system, method and devices of the invention each have several aspects, none of which individually is solely responsible for its desirable attributes. Without limiting the scope of this invention, its most salient features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled "Detailed Description of Certain Modalities", it will be understood how the features of this invention provide advantages over other types of luminous screens. In one embodiment, a luminous screen is provided. The luminous screen includes the plurality of light modulating elements, at least some of which have different reflection values against one or both of an address pulse amplitude at the address pulse voltage level. Also provided is a routing circuit configured to provide amplitude addressing and / or variable voltage level pulses to the plurality of elements, so that different combinations of elements change in a selected form, depending on the amplitude and / or level of voltage of the steering pulses, and wherein the addressing circuit is configured to provide a first pulse to which all the elements of the plurality of elements respond and at least a second pulse to which less than all the plurality of elements respond. In another embodiment, a luminous screen is provided. The luminous screen includes a plurality of MEMS elements arranged in rows, where the MEMS elements of each of the rows are further arranged in sub-rows and where the sub-rows of each row are electrically connected. In this embodiment, a plurality of resistances are also provided, each of the resistors being connected to one of the respective sub-rails, the respective resistances for each of the sub-rails of each row having a resistance different from that of the resistors connected to the other sub-rows of the row. In another embodiment, a method for addressing a plurality of luminous screen elements having at least a first and a second luminous screen element and characterized by respective response thresholds includes generating a first pulse 'characterized by a parameter having a higher value. that the threshold of response of all the plurality of the elements of the luminous screen and apply the first impulse to the plurality of elements of the luminous screen. further, a second pulse is generated characterized by a parameter having a value greater than the response threshold of the first element of the luminous display and less than the response threshold of the second element of the luminous display. The second pulse is applied to the plurality of elements of the luminous screen. In another embodiment, an actuator circuit for directing a plurality of elements of the luminous screen having at least a first and a second element of the luminous display and characterized by respective response thresholds include means for generating a first pulse characterized by a parameter that it has a value greater than the response threshold of the whole plurality of elements and means for applying the first pulse to the plurality of element of the luminous screen. The actuator circuit also includes means for generating a second pulse characterized by a parameter having a value greater than the threshold of response of the first element of the luminous screen and less than the threshold of response of the second element of the luminous screen and means for applying the second impulse of the plurality of elements of the luminous screen. Another modality includes a device. The device comprises a plurality of means for modulating light, the modulating means having different deflection variables for a selected applied voltage. The luminous screen further comprises addressing means for providing steering pulses of the variable voltage level to the plurality of elements, so that different combinations of the modulating means change selectively, depending on the voltage level of the steering pulses. The addressing means is configured to provide a first pulse to which all the modulating means of the plurality of elements respond and at least one second pulse to which less than all the modulating means respond. Another embodiment comprises a method for manufacturing a luminous screen. The luminous screen comprises providing a plurality of MEMS elements arranged in rows. The MEMS elements of each of the rows are arranged in sub-rows. The sub-rows of each row are electrically connected. The method also comprises connecting a plurality of resistors to the MEMS elements. Each of the resistors connected to one of the respective sub-rows. The respective resistances for each of the sub-rows of each row each have different resistance to that of the resistors connected to the other sub-rows of the row. Another modality provides a luminous screen. The luminous screen comprises: a plurality of display means arranged in rows, where the display means of each of the rows are further arranged in sub-rows and where the sub-rows of each row are electrically connected. The luminous screen also comprises a plurality of means for resisting the electric current, each of the resistance means connected to one of. the respective sub-rows, the respective resistance means having for each of the sub-rows of each row a resistance different from that of the resistance means connected to the other sub-rows of the row.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an isometric view describing a portion of a mode of a luminous display of the interferometric modulator in which a moving mirror of a first interferometric modulator is in a reflective position, or "on", to a predetermined distance of a fixed mirror and the moving mirror of a second interferometric modulator is in a non-reflective, or "off" position. Figure 2 is a block diagram of the system illustrating a modality of an electronic device incorporating a luminous display of the 3 x 3 interferometric modulator. Figure 3 is a diagram of the position of the moving mirror against the applied voltage for a modality. Example of an interferometric modulator of Figure 1. Figure 4 is an illustration of row and column voltage sets that can be used to drive a light display of the interferometric modulator. Figure 5A illustrates an exemplary data box of the luminous display on the luminous display of the 3 x 3 interferometric modulator of Figure 2. Figure 5B illustrates an exemplary timing diagram for row and column signals that can be used for writing the box of Figure 5A. Figure 6A is a cross section of the device of Figure 1. Figure 6B is a cross section of an alternative mode of an interferometric modulator. Figure 6C is a cross section of an alternative mode of an interferometric modulator. Figure 7 is a partial schematic diagram of a mode of a light display of interferometric modulator in which the rows have been subdivided into 4 sub-rows sharing a connection of the common actuator. Figure 8 is a timing diagram illustrating a series of row and column signals applied to the upper row of the arrangement mode of Figure 7 to produce the illustrated light screen arrangement. Figure 9 is a diagram, similar to that of the Figure 3, of the position of the moving mirror against the applied positive voltage illustrating an exemplary embodiment of a pair of interferometric modulators having nested stability windows. Figure 10 is a timing diagram illustrating a series of row and column signals applied to the upper row of the array mode of Figure 7 to produce the illustrated light array arrangement. Figure 11 is a flowchart illustrating one embodiment of an interferometric modulator arrangement driving method as described with respect to Figures 6 and 7. Figures 12A and 12B are block diagrams of the system illustrating one embodiment of the invention. a visual luminous display device comprising a plurality of interferometric modulators.

Detailed Description of Preferred Modes In preferred embodiments, the invention addresses a group of luminous screen elements with a driving signal applied through a common actuator connection to the group of elements of the luminous screen. The luminous screen can thus produce more shades of gray, or color, with a smaller number of wires than would be necessary if the driving signal of each element of the luminous screen were applied through separate wires to each element of the luminous screen.

The following detailed description is directed to certain specific embodiments of the invention. However, the invention can be incorporated in a multitude of different ways. In this description, reference is made to the drawings where similar parts are designated with similar numbers through them. As will be apparent from the following description, the invention can be implemented in any device that is configured to present an image, whether in motion (eg, video), or stationary (eg, static image), and either textual or descriptive. More particularly, it was contemplated that the invention may be implemented or associated with a variety of electronic devices such as, but not limited to, mobile phones, wireless devices, personal data assistants (PDA), manual or portable computers, receivers / browsers. GPS, cameras, MP3 players, video cameras, game consoles, wristwatches, clocks, calculators, television monitors, flat-panel light displays, computer monitors, automobile light displays (for example, light-emitting diodes, etc.), controls and / or pilot light displays, light displays of camera views (for example, backlighting of a rear view camera in a vehicle), electronic photographs, boards or electronic signs, projectors, architectural structures (for example, tile arrangements), packages, aesthetic structures (for example presentation of images on a piece of ^ Jewelry). More generally, the invention can be implemented in electronic switching devices. The spatial light modulators used for application in image formation come in many different forms. The modulators of luminous liquid crystal display (LCD) transmitters regulate the light controlling the torsion and / or alignment of the crystalline material to block or let in light. The spatial light modulators reflectors exploit various physical effects to control the amount of light reflected to the imaging surface. Examples of these 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. A luminous display mode of the interferometric modulator comprising a reflector MEMS luminous screen element is illustrated in Figure 1. In those devices, the pixels are in a bright or dark state. In the bright state ("on" or "open"), a bistable luminous screen element reflects the incident light to a user. When in the dark state ("off" or "closed"), an element of the bistable luminous screen absorbs light and reflects little light to the user. Depending on the mode, the luminous screen 110 may be configured to reflect light in the "off" state and absorb light in the "on" state, ie, the reflectance properties of the light of the "on" and "off" states. "off" are reversed. MEMS pixels can also be configured to reflect only selected colors, producing a luminous screen of color instead of black and white. Figure 1 is a perspective view, isometric, describing two adjacent pixels in a row of a modality of a visual luminous screen, comprising a MEMS interferometric modulator. A luminous display of the interferometric modulator comprises an array of rows / columns of these interferometric modulators. Each interferometric modulator includes a pair of mirrors positioned at a distance from each other to form a resonant optical cavity. In one embodiment, one of the mirrors can move between at least two positions. In the first position, the moving mirror is placed at a first distance from the other mirror so that the interferometric modulator is predominantly reflective. In the second position, the moving mirror is placed at a different distance, for example, adjacent to the fixed mirror, so that the interferometric modulator is predominantly absorbent. The described portion of the array of the pixel includes two adjacent interferometric modulators 12a and 12b in a row. In the described mode of the interferometric modulator, a moving mirror 14a is illustrated in the reflective position ("released", "on" or "open") at a predetermined distance from a partial mirror, fixed 16a, 16b. The moving mirror 14b of the interferometric modulator 12b is illustrated in the non-reflective, absorbent position ("driven", "off", or "closed") adjacent to the partial mirror 16b. The fixed mirrors 16a, 16b are electrically conductive, and can be manufactured, for example, by depositing layers of chromium oxide and indium and tin on a transparent substrate 18 which are arranged in parallel strips and can form column electrodes. The movable mirrors 14a, 14b along the row can be formed as a series of parallel strips of a deposited metal layer or layers (orthogonal to the column electrodes 16a, 16b) on the substrate 18, with the aluminum being the suitable material, and can form rows of electrodes. When a potential difference is applied to a selected row and column, the capacitor formed at the intersection of the row and column electrodes at the corresponding pixel charges, the electrostatic forces pull the electrodes together. If the voltage is high enough, the mobile electrode is forced against the stationary electrode (a dielectric material can be deposited on the stationary electrode to avoid shortening and controlling the separation distance) as illustrated by the pixel on the right in Figure 1 The behavior is the same regardless of the polarity of the applied potential difference. In this way, the row / column drive can control the state of reflection against the absorbing state of each pixel. Figures 2 to 5B illustrate an exemplary process and system for using a. arrangement of inter-parametric modulators in a visualization application. Figure 2 is a block diagram of the system illustrating a modality of an electronic device that can incorporate aspects of the invention. In the exemplary embodiment, the electronic device includes a processor 20 which can be any microprocessor of a single or multiple integrated microcircuits for general purposes such as an ARM, Pentium®, Pentium II®, Pentium III®, Pentium IV®, Pentium® Pro , an 8051, a MIPS®, a Power PC®, an ALPHA®, or any xmicroprocessor for special purposes such as a digital signal processor, microcontroller, or an array of programmable gates. As is conventional in the art, the processor 20 may be configured to execute one or more system modules and programming programs. In addition to running an operating system, the processor can be configured to execute one or more applications of programs and programming systems, including a network browser, a telephone application, an email program, or any other application of software and systems. programming. In one embodiment, the processor 20 is also configured to communicate with an array controller 22. In one embodiment, the array controller 22 includes a row driver circuit 24 and a column driver circuit 26 that provide signals to the array 30. The cross section of the arrangement illustrated in Figure 1 is shown by the lines 1-1 in Figure 2. Portions of the array controller 22 as well as additional circuits and functionalities may be provided by a graphics controller that is typically connected between the actuators of the array. the current luminous screen and a microprocessor for general purposes. Exemplary forms of the graphics driver include the 69030 or 69455 drivers from Chips and Technology, Inc., the S1D1300 series from Seiko Epson, and the Solomon Systéch 1906. For MEMS interferometric modulators, the row / column drive protocol can take advantage of a hysteresis property of those devices illustrated in Figure 3. A potential difference of 10 volts may be required, for example, to cause a pixel to deform from the released state to the driven state. Nevertheless, when the voltage is reduced from that value, the pixel may not be released until the voltage drops below 2 volts. There is in this way the voltage range, of about 3 a. 7 V in the example illustrated in Figure 3, where there is a stability window within which the device will remain in any state in which it started. The row / column drive protocol is therefore designed so that during the selection of the row, the pixels in the selected row that are driven are exposed to a voltage difference of approximately 10 volts, and the pixels that are going to be released are exposed to a voltage difference close to zero volts. After selection, the pixels are exposed to a steady-state voltage difference of about 5 volts so that they remain in any state in which they were placed by the row selection. After being written, each pixel observes a potential difference within the "stability window" of 3-7 volts in this example. This characteristic makes the design of the pixel illustrated in Figure 1 stable under the same applied voltage conditions in any pre-existing triggered or released state. Since each pixel of the interferometric modulator, either in the actuated or released state, is essentially a capacitor formed by the fixed and moving mirrors, this stable state can be maintained at a voltage within the hysteresis window with almost no energy dissipation. Essentially no current flows to the pixel if the mirror is not moving and if the applied potential is fixed. In typical applications, a display box can be created by holding the set of electrodes of the column according to the desired set of pixels driven in the first row. A row pulse is then applied to the electrode of row 1, driving the pixels corresponding to the lines of the sustained column. The sustained set of column electrodes is then changed to correspond to the desired set of pixels operated in the second row. Then an impulse is applied to the electrode of column 2, holding the appropriate pixels in row 2 of ac erdo with the column electrodes held. The pixels of row 1 are not affected by the pulse of row 2, and remain in the state they were in during the pulse of row 1. This can be repeated for the entire series of rows in a sequential fashion to produce picture. Generally, the tables are renewed and / or updated with the display data by continuously repeating this process at some desired number of frames per second. A wide variety of protocols for driving row and column arrays of pixel arrays to produce display frames are also known and may be used in conjunction with the present invention. Figures 4, 5A and 5B, illustrate a possible drive protocol for creating a display box on the 3x3 array of Figure 2. Figure 4 illustrates a possible set of column and row voltage levels that can be used for pixels exhibiting the hysteresis curves of Figure 3. In the embodiment of Figure 4, actuating the pixel involves setting the appropriate column in -VdeSky, and the appropriate row +? V. The release of the pixel is achieved by fixing it in the appropriate column to + V of? ViaCión, and the appropriate row to it +? V. In those rows where the row voltage is kept at zero volts, the pixels are stable in whatever state they were originally in, regardless of whether the column is in + V deviation O - v deviation - Figure 5B is a timing diagram which shows a series of row and column signals applied to the 3X3 array of Figure 2, which will result in the display arrangement illustrated in Figure 5A where the driven pixels are not reflective. Before writing the illustrated picture of Figure 5A, the pixels can be in any state, and in this example, all the rows are at 0 volts, and all the columns are at +5 volts. In this state, all pixels are stable in their existing triggered or released states. In the frame of Figure 5A, the pixels (1,1), (1,2), (2,2), (3,2) and (3,3) are driven. To achieve this, during a "line time" for row 1, columns 1 and 2 are set to -5 volts, and column 3 is set to +5 volts. This does not change the state of any of the pixels, because all the pixels remain in the stability window of 3-7 volts. The row 1 is then selected with a pulse ranging from 0, up to 5 volts, and again to zero. This triggers the pixels (1,1) and (1,2) and releases the pixel (1,3). No other pixel in the array is affected. To set row 2 as desired, column 2 is set to -5 volts, and columns 1 and 3 are set to +5 volts. The same selection applied to row 2 will then trigger the pixel (2.2) and release the pixels (2,1) and (2,3). Again, none of the other pixels in the array will be affected. Row 3 is similarly fixed by setting columns 2 and 3 to -5 volts, and column 1 to +5 volts. The selection of row 3 fixes the pixels of row 3 as shown in Figure 5A. After writing the chart, the row potentials are zero, and the potentials of the column can remain at +5 or -5 volts, and the luminous screen is then stable in the array of Figure 5A. It will be appreciated that the same procedure can be employed for arranging dozens or hundreds of rows and columns. It will also be appreciated that the timing, sequence and voltage levels used to effect the row and column drive can vary widely within the general principles outlined above, as in the previous example it is exemplary only, and any voltage method can be used. drive with the present invention. The details of the structure of the interferometric modulators that operate in accordance with the principles set forth above can vary widely. For example, Figures 6A-6C illustrate three different embodiments of the mobile mirror structure. Figure 6A is a cross section of the embodiment of Figure 1, where a strip of metal material 16 is deposited on orthogonally extending supports 18. In Figure 6B, the moving mirror is attached to supports at the corners only, on the obstacles 32. In Figure 6C, the mirror 16 is suspended from a deformable film 34. This embodiment has benefits because the design and structural materials used for the mirror -16 can be optimized with respect to the optical properties, and The structural design and material used for the deformable layer 34 can be optimized with respect to the desired mechanical properties. The production of various types of interferometric devices are described in a variety of published documents, including, for example, the US Application, published 2004/0051929, which is incorporated herein by reference in its entirety.

The data describing a monochromatic luminous screen image may include one data bit per pixel. One mode of a monochromatic luminous screen includes an interferometric modulator per pixel, the on or off state of the modulator being set based on the value of one bit of data per pixel. A grayscale image can include several bits of data per pixel. For example, a "3-bit" greyscale display includes 3 data bits per pixel that correspond to one of eight shades of gray that can be assigned to each pixel. One modality of a luminous screen for displaying an exemplary 3-bit gray scale image includes three interferometric modulators for each pixel. To obtain the eight tones, the three modulators reflect light according to a ratio of 1: 2: 4. In that embodiment, each of the interferometric modulators includes mirrors that have a reflective surface area that varies according to the 1: 2: 4 ratio. A particular tone in a pixel is obtained in a mode by setting each modulator to an on or off state based on the binary value of a corresponding bit of the 3 data bits. One mode of the color luminous screen works similarly, except that the color luminous screen includes a group of red, green, and blue interferometric modulators. For example, in a bright 12-bit color display, 4 of the 12 bits correspond to each of 16 intensities of red, green, and blue which are produced by interferometric modulators of red, green, or blue. That luminous screen in grayscale color b have more presentation elements to address than a bright monochromatic screen. To address those presentation elements for those modalities of light gray or color screens, the number of electrical connections to the control of the luminous screen increases. For example, in a 3x3 3-bit gray scale luminous screen mode, each of the rows is subdivided into 3 sub-rows. Each pixel of a modality of the luminous screen comprises the interferometric modulators of the three sub-rows. One of those modes has actuator connections of 3 * 3 = 9 rows and 3 column actuator connections for a total of twelve actuator connections instead of 6 for a 3x3 monochromatic luminous display. One way to reduce the number of actuator connections is to electrically connect together a group of modulators, for example, the 3 sub-rows in the 3-bit gray scale mode discussed above, and to drive the group with a signal that changes the state of a subset of the electrically connected group. For example, one way of selectively addressing a group of electrically connected interferometric modulators is to apply a drive signal on a pulse that is not of sufficient duration to change the state of some of the group of modulators. Generally, the period of time for a particular modulator on the luminous screen to change the state in response to the leading edge of the row selection can be referred to as the response type, t. Note that the term "response time" may refer to the time for an interferometric modulator to move from a reflector to a non-reflective state or the time for the modulator to move from the non-reflective state to the reflector state. In a mode of the luminous display of the interferometric modulator, the period of time t is conceptually the sum of an electric response time, tRC, and a mechanical response time, TM. With respect to the electrical response time, each of the interferometric modulators in the luminous screen forms a respective circuit that can be characterized by a time and resistance constant of a capacitor (RC). The electric response time, rRC, is the time period of the leading edge of the row selection pulse at the time at which the circuit is charged to the drive or release voltage through the mirrors. The mechanical response time, rM, is the period of time for the moving mirror to physically change positions once the drive or release voltage has been reached. The time for the modulator to move to a new position, tM, depends on factors such as the spring constant associated with the moving mirror of the modulator and the air resistance of the mirror when it moves. One mode of the luminous screen includes groups of modulators electrically connected with different response times. Applying a common impulse to the group of modulators that is shorter than the response time of some of the modulators but longer than the response time of the other modulators, the state of the different combinations of the modulators can be fixed. Figure 7 is a partial schematic diagram of a mode of a light display of the interferometric modulator, similar to that shown in Figure 5A, in which the rows have been subdivided into four sub-rows that share a common actuator connection. Each of the sub-rows defines an interferometric modulator in each column. As discussed above, if a row selection is applied for a time that is less than the response time, the mobile mirror of the interferometric modulator substantially maintains its position. In the embodiment of Figure 7, the interferometric modulators of the sub-rows are described from top to bottom with decreasing response times. In that embodiment, the interferometric modulators of the sub-rows can be addressed via the connection of the common actuator by suitably varying the duration of the row selection to change the state of only the selected portion of the sub-rows. Response times in an interferometric modulator are affected by the resistance-capacitor (RC) time characteristic of the actuator circuit, including the modulator, that is, the time for the moving mirror of the modulator to be charged at a particular voltage, the mechanical properties of the modulator, and the resistance of the moving mirror to move through the air. In the modality described in Figure 7 and the response times of the interferometric modulators along the sub-rows vary by varying the RC time of the modulators in each sub-row. More particularly, in Figure 7, each of the sub-rows is connected via a resistor that provides a progressively smaller resistance for each sub-row from top to bottom. When a voltage is applied between the modulators' mirrors, those with the largest resistance take longer to charge, and thus it takes longer for the voltage difference to fall out of the stability window for a sufficient time to that the moving mirror is activated to a new position. Figure 8 is a timing diagram illustrating a series of row and column signals applied to the upper row (Row 1) of the arrangement mode of Figure 7 to produce the illustrated light screen arrangement. The row and column signals in one embodiment are similar to those described in Figure 5B, except that a series of pulses is applied for each row to address each of the sub-rows with each of the pulses varying in duration. The reflecting state of the luminous display at the end of each on-line time is illustrated graphically in Figure 7 below each of the pulses of each respective line time. The pulses are applied during a series of line times per row, one line time per sub-row. The row pulses for each of these line times have magnitudes of +5 volts and a variable duration (decreasing from left to right). The decrease in direction is selected so that the row pulses that address only those modulators in the sub-rows that have response times shorter than the row pulses. The pulses of Figure 8 set the state of the luminous screen that is described in Figure 7 as follows. For the first line time for Row 1, Column 1, a column potential of -5 volts is applied along with the row pulse of +5 volts to set the state of the modulators of each of the sub-rows in the position actuated as illustrated along the bottom of Figure 8. The potential of Column 1 remains at -5 during the row times of Row 1 remaining to keep each of the elements of the sub-rows in the actuated position . In Column 2, a +5 volt potential is applied in conjunction with the row pulse in the first line time to release all modulators from the sub-rows in Column 2. During the second line time for Row 1, a potential of Column 2 of -5 volts is applied in conjunction with the row pulse to drive the two inner sub-rows of Row 1. The duration of the row pulses in the second line time is shorter than the response times of the upper sub-rows, so that the modulator states in the upper sub-rows are maintained. During the third row time for Row 1, a potential of Column 2 is applied at -5 volts in conjunction with the row pulse to drive the modulator in the lower sub-row. Again, the row pulse duration of the third row time is shorter than the response time of the modulators in all except the lower sub-rows, so that only the state of the lower row changes. The set of pulses for Column 3 is applied according to Figure 8 to set the state of the sub-rows of Column 3. In the illustrated embodiment, each of those line times for a row is approximately the same. Nevertheless, it should be recognized that other modalities, line times may be shorter, for example, line times for a row may be shortened to correspond to the shorter row pulse durations for each row line times . In addition, any other suitable drive voltage scheme may be used in place of the exemplary scheme described in Figures 5B and 7. In addition, although the sub-rows in the illustrated embodiment include variable resistors that vary the RC time of the sub-rows, in others modalities, the sub-rows may have capacitances, variable resistances, or a combination thereof. In some embodiments, the response time of the interferometric modulators varies on the basis of a damping force on the moving mirror ^ caused by the movement of the mobile mirror against the air in the small cavity since this forces the air (or other gas) to leave the cavity between the moving mirror and the fixed mirror. The damping force acts as a resistance to the movement of the moving mirror through the air. In one embodiment, this force is varied by forming holes in the moving mirror to reduce the air pressure against the moving mirror when it is actuated and thereby changing the electromechanical response of the actuator. In another embodiment, the holes are formed in the deformable film 34 of 6C. Other similar modalities of interferometric modulators with variable response times are discussed in U.S. Patent Application No. 10 / 794,737, filed March 3, 2004. In one embodiment, the response time of the interferometric modulators of the sub-rows varies on the basis of of the variation of a combination of one or more of the characteristics of RC, the spring constant, or the air damping force.

In other embodiments, other mechanical properties of the interferometric modulators can be varied to vary the mechanical response times of the interferometric modulators between the sub-rows. The response time depends on several factors that can vary, including the thickness, mass or material of the moving mirror 14 or the deformable layer 34 of Figure 6C. In some embodiments, the interferometric modulators in each of the sub-rows may have different spring constants. The modalities can also vary the response times by varying the thicknesses, positions or composition of the support. Instead of having variable response times, other modes, the interferometric modulators of each of the sub-arrays can have variable drive and release voltages to allow a set of electrically connected sub-arrays to be individually addressed. Figure 9 is a diagram similar to that of Figure 3, of the position of the moving mirror versus the applied positive assembly illustrating an exemplary embodiment of three interferometric modulators having respective nested stability. The hysteresis window nested further in, indicated by the dashes 802, has drive and release voltages that have a magnitude of 8 to 4 volts, respectively. The next nested hysteresis window, indicated by the traces 804, has drive and release voltages which have magnitudes of 10 and 2 volts, respectively. The outermost hysteresis window, indicated by the traces 804, has drive and release assemblies having a magnitude of 12 and 0 volts, respectively. The hysteresis window of the modulators associated with each sub-row can be selected by varying the geometry and materials of the modulators. In particular, the amplitude (difference between the drive and release voltages), the location (the absolute values of the drive and release voltages), and the relative values of the drive and release voltages can be selected by varying the geometrical properties and modulators material. The properties that can be varied may include, for example, the distance between the mobile mirror supports, the mass associated with the moving mirror in relation to the spring constant, the thickness, the tensile stress, or the stiffness of the mirror and / or the layers on the mechanism that moves the mirror, the dialectical constant or thickness of the dialectical layer between the stationary electrode and the mobile electrode. Further details of the selection of hysteresis properties of the interferometric modulators are described in U.S. Patent Application No. 60 / 613,382 '- entitled "METHOD AND DEVICE FOR SELECTIVE ADJUSTMENT OF THE HYSTERESIS WINDOW" presented on September 27, 2004. - In one of these modalities, the interferometric modulators are arranged in sub-rows as in Figure 8. The modulators of each of the sub-rows have hysteresis stability windows that are nested with each other. In the illustrated embodiment, the stability windows are nested from the outside inwards, like the windows described in Figure 9, of the sub-row above the lower sub-row. Figure 10 is a timing diagram illustrating a series of row and column signals applied to the first row (Row 1) of that arrangement mode to produce an illustrated light screen arrangement. The row and column signals in one mode are similar to those described in Figure 8, except that row pulses vary in magnitude more than in duration. The row pulses decrease in magnitude from left to right, which correspond to the sub-rows from top to bottom. This decrease in the magnitude of the pulses is selected to address only those modulators in the sub-rows that have smaller drive voltages / larger release. For example, in an illustrated embodiment, +6 and -6 volt potentials are applied to the columns and row pulses of 2.6.4 volts are applied to the rows. "- The pulses of Figure 8 set the status of the luminous screen described in Figure 7 as follows: For the first line time for Row 1, Column 1, a potential of -6 volts is applied along with the row pulse of +6 volts to set the modulator status of each of the sub-lines in the driven position as illustrated along the bottom of Figure 8. The potential of column 1 remains at -6 volts for row line 1 times remaining to continue setting the state of each element in the sub-rows in the driven position In column 2 a potential of +6 volts is applied in row pulse set to +6 volts in the first line time to release all the modulators in the sub-rows in column 2. During the second line time for row 1, a potential of -6 volts of column 2 is applied in conjunction with the row pulse of + 4 volts to drive the do s sub-rows of lower row 1. During the third row time for Row 1, a potential of Column 2 is applied to -6 volts in conjunction with the row pulse of +2 volts to drive the modulator of the lower sub-row. The set of pulses of Column 3 is applied according to Figure 8 to set the state of the sub-rows of Column 3. Figure 11 is a flow chart illustrating a modality of a method 850 for updating a modality of a luminous display as Figures 6 and 9. The method of 850 starts at block 852 in which the actuator 22 of Figure 2 receives the image data value for a sub-row. In one embodiment, the actuator 22 receives the data value from the frame buffer. Next in block 854, the actuator 22 applies a row selection to all sub-rows of the interferometric modulators together with a column potential corresponding to the image data value. Moving to block 856, the actuator 22 receives the data for the next sub-row. Next in block 860 the acts of blocks 854 and 856 are repeated for each of the sub-rows. In one embodiment, the acts of blocks 854 and 856 at least partially concurrently.

Figures 12A and 12B are block diagrams of the system illustrating one embodiment of a luminous display device 2040. The luminous display device 2040 may be, for example, a cellular or mobile telephone. However, the same components of the luminous screen device 2040 or slight variations thereof are also illustrative of the different types of luminous screen devices such as televisions and portable media players. The luminous display device 2040 includes a housing 2041, a luminous display 2030, an antenna 2043, a loudspeaker 2045, an input device 2048, and a microphone 2046. The housing 2041 is generally formed from any of a variety of processes of manufacture as is well known to those skilled in the art, including injection molding and vacuum forming. In addition, the housing 2041 can be made from any of a variety of materials, including, but not limited to, plastic, metal, glass, rubber and ceramic, and combinations thereof. In one embodiment, housing 2041 includes removable portions (not shown) that can be exchanged with other removable portions of different colors, or contain different logos, images or symbols.

The luminous screen 2030 of the exemplary luminous display device 2040 may be any of a variety of luminous displays, including a bistable luminous display, as described herein. In other embodiments, the 2030 luminous screen includes a flat-panel luminous screen, such as plasma, EL, OLED, STN LCD, or TFT LCD as described above, or a flat-panel luminous screen, such as a CRT or other device. of tube, as is well known to those skilled in the art. However, for purposes of describing the present embodiment, the luminous screen 2030 includes a luminous display of interferometric modulator, as described herein. The components of a modality of exemplary luminous display device 2040 are illustrated schematically in Figure 12B. The illustrated exemplary luminous display device 2040 includes a housing 2041 and may include additional components at least partially enclosed therein. For example, in one embodiment, the exemplary luminous display device 2040 includes a network interconnection 2027 that includes an antenna 2043 which is coupled to a transceiver 2047. Transceiver 2047 is connected to processor 2021, which is connected to the components conditioning physicists 2052. The conditioning physical components 2052 may be configured to condition a signal (e.g., filter a signal). The physical conditioning components 2052 are connected to a loudspeaker 2045 and a microphone 2046. The processor 2021 is also connected to an input device 2048 and a driver 'of the actuator 2029. The driver controller 2029 is coupled to an intermediate memory box 2028 and the array actuator 2022, which in turn is coupled to a luminous display array 2030. A 2050 power supply provides power to all components as required by the design of the exemplary luminous display device 2040 , particular. The interconnection or network interface 2027 includes the antenna 2043 and the transceiver 2047 so that the exemplary luminous display device 2040 can communicate with one or more devices on the network. In one embodiment the network interface 2027 may also have some processing capabilities to alleviate the requirements of processor 2021. 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 IEEE 802.11 standard, including IEEE 802.11 (a), (b) or (g). In another embodiment, the antenna transmits and receives RF signals according to the BLUETOOTH standard. In the case of a cell phone, the antenna is designed to receive CDMA, GSM, AMPS or other known signals that are used to communicate within% of a wireless cellular telephone network. The transceiver 2047 preprocesses the received signals from the antenna 2043 so that they can be received by and further manipulated by the processor 2021. The transceiver 2047 also processes the signals received from the processor 2021 so that they can be transmitted from the exemplary luminous display device 2040 via the antenna 2043. In an alternative embodiment, the transceiver 2047 can be replaced by a receiver. In 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. For example, the image source may be a video disc digital (DVD) or a hard disk drive containing image data, or a software and programming system module or software that generates image data. The processor 2021 generally controls the total operation of the exemplary luminous display device 2040. The processor 2021 receives data, image data comprised of the network interconnect 2027 or an image source, and processes the data in raw or untreated image data. a format that is easily processed in untreated image data. The processor '2021 then sends the processed data to the controller of the driver 2029 or the frame buffer 2028 for storage. The untreated data typically refers to the information that identifies the characteristics of the image in each place within an image. For example, those characteristics of the image may include color, saturation and scale level of gray. In one embodiment, processor 2021 includes a microcontroller, CPU, or logic unit to control the operation of exemplary luminous display device 2040. In physical computing components or conditioning hardware 2052 generally includes amplifiers and filters for transmitting signals to loudspeaker 2045, and to receive signals from the microphone 2046. The physical computing components or conditioning hardware 2052 may be discrete components within the exemplary luminous display device 2040, or they may be incorporated within the processor 2021 or other components. The driver of the driver 2029 takes the raw image data generated by the processor 2021 either directly from the processor 2021 or from the frame buffer 2028 and reformats the image data untreated appropriately for high transmission speed to the actuator of the array 2022. Specifically, the driver of the actuator 2029 again formats the raw image data into a data stream having a format similar to that of a frame, so that it has an adequate time order for its scanning through the arrangement of the luminous display 2030. Then the driver of the actuator 2029 sends the formatted information to the actuator of the array 2022. Although a driver of the actuator 2029, such as an LCD controller, is often associated with the system processor 2021 As an autonomous Integrated Circuit (CI), those controllers can be implemented in many ways. They can be included in the 2021 processor as physical components or hardware, included in the 2021 processor as programs and programming or software systems, or fully integrated into the physical components with the 2022 array actuator. Typically, the 2022 array actuator receives the formatted information of the driver of the 2029 driver and re-format the video data in a parallel set of waveforms that are applied many times per second to the hundreds and sometimes thousands of wires that come from the matrix of pixels x and of the luminous screen. '• In a modality, the driver of the actuator 2029, the controller of the array 2022, and the array of the luminous screen 2030 are suitable for any of the types of luminous screens described herein. For example, in one embodiment, the driver controller 2029 is a conventional luminous display controller or a bistable luminous screen controller (e.g., an interferometric modulator controller). In another embodiment, the actuator of the array 2022 is a conventional actuator or a bistable luminous screen actuator (e.g., a luminous display of interferometric modulator). In one embodiment, a driver of the 2029 actuator is integrated with the actuator of the 2022 array. This mode is common in highly integrated systems such as cell phones, wristwatches, and other small-area light displays. In yet another embodiment, the arrangement of the luminous screen 2030 is a typical luminous screen arrangement or a bistable luminous screen arrangement (for example a luminous screen including an array of interferometric modulators).

The input or power device 2048 allows a user to control the operation of the exemplary luminous display device 2040. In one embodiment the 2048 input device includes a 'numeric keypad, such as a QWERTY keyboard or a telephone keypad, a button, a switch or switch, a touch-sensitive screen, a membrane sensitive to pressure or heat. In one embodiment, the microphone 2046 is an input device for the exemplary luminous display device 2040. When the microphone 2046 is used to feed data to the device, voice commands may be provided by the user to control the operation of the display device. luminous exemplary 2040. The 2050 power supply may include a variety of energy storage devices as is well known in the art. For example, in one embodiment, the 2050 power supply is a rechargeable battery, such as a nickel-cadmium battery or a lithium-ion battery. In another embodiment, the 2050 power supply is a renewable energy source, a capacitor, or a solar cell, including a plastic solar cell, and a "solar cell" paint In another embodiment, the 2050 power supply is configured to receive power from a wall outlet In some implementations the control programmability resides, as described above, in an actuator controller, which can be located in various places in the electronic light display system. Programmability of control resides in the actuator of the array 2022. Those skilled in the art will recognize that the optimization described above can be implemented in any number of physical components or hardware and / or programs and programming or software systems and in various configurations. It should be recognized that although certain modalities described here are discussed with respect to "rows" and "column" s ", those terms are used for convenience only to describe those modalities. In other embodiments, the properties attributed to the rows or columns in the exemplary embodiments may be completely or partially reversed as would be apparent to one skilled in the art. In addition, although the embodiments are illustrated in FIGS. 7 and 9B with respect to a particular drive scheme, any other suitable scheme may be adapted to vary the duration or magnitude of the pulses applied according to the description of the invention. In addition, although in one embodiment, the groups of interferometric modulators that share a common actuator connection are arranged in sub-arrays, it must be recognized that other modalities may include any array of interferometric modulator groups. In addition, although certain modalities have been discussed with respect to interferometric modulator groups electrically connected with different response times, and certain other modalities discussed with respect to groups of interferometric modulators electrically connected with different hysteresis stability windows, other embodiments may include groups of electrically connected modulators having different response times and different hysteresis stability windows. These modalities can be addressed using a series of pulses that vary in both duration and voltage. Although the above detailed description has shown, described, and pointed out novel features of the invention as being applied to various modalities, it should be understood that various omissions, substitutions, and changes in the form and details of the device or process illustrated by those may be made. skilled in the art without departing from the spirit of the invention. The scope of the invention is indicated by the appended claims rather than by the foregoing description. All changes that fall within the meaning and scope of equivalence of the claims will be encompassed within its scope.

Claims (37)

1. NOVELTY OF THE INVENTION Having described the invention as above, property is claimed as contained in the following:
2. - CLAIMS 1. A device, characterized in that it comprises: * • a plurality of means for modulating light, the modulating means having different deflection values for a selected applied assembly; and addressing means for providing variable voltage level addressing pulses to the plurality of elements, so that different combinations of the modulating means change in a selectable manner, depending on the voltage level of the addressing pulses, wherein the means of The addresses are configured to provide a first pulse to which all the modulating means of the plurality of elements respond and at least one second pulse to which less than all the modulating means respond. The device according to claim 1, characterized in that at least one of the modulating means comprises an interferometric modulator.
3. 3. The device according to claim 1 or 2, characterized in that the addressing means comprise an actuator circuit. .
4. The device according to claim 1, characterized in that it additionally comprises: a processor that is in electrical communication with modulating means, the processor being configured to process image data; and a memory device in electrical communication with the processor.
5. The device according to claim 4, characterized in that it additionally comprises a controller configured to send at least a portion of the image data to the driver circuit.
6. The device according to claim 4, characterized in that it additionally comprises an image source module configured to send the image data to the processor.
7. The device according to claim 6, characterized in that the image source module comprises at least one of a receiver, a transceiver, and a transmitter.
8. 8. The device according to claim 4, characterized in that it further comprises an input device configured to receive input data and to communicate the input data to the processor.
9. The device according to claim 1, characterized in that at least one of the same modulators has different mechanical structures with respect to one another in order to affect differently the values of the deflection against the applied voltage.
10. The device according to claim 9, characterized in that at least one of the modulating means have different film thicknesses with respect to others in order to affect differently the values of deflection against the applied voltage.
11. The device according to claim 10, characterized in that the different film thicknesses comprise different thicknesses of an insulating layer between a deflecting electrode and a non-deflecting electrode.
12. 12. A method of addressing a plurality of luminous screen elements having at least one first and second luminous screen elements and characterized by respective response thresholds, the method is characterized in that it comprises: generating a first impulse characterized by a parameter which has a value greater than the response threshold of all the plurality of elements of the luminous screen; apply the first impulse to the plurality of the elements of the luminous screen; generating a second pulse characterized by a parameter having a value greater than the response threshold of the first element of the luminous display and less than the response threshold of the second element of the luminous display; and applying the second pulse to the plurality of elements of the luminous screen.
13. The method according to claim 12, characterized in that the parameter comprises a pulse duration and the response threshold comprises a response time of the respective element of the luminous screen.
14. The method according to claim 12, characterized in that the parameter comprises a voltage variable and the response threshold comprises a driving voltage of the respective element of the luminous screen.
15. 15. The method according to claim 12, characterized in that the state of the second element is maintained.
16. 16. The method according to claim 12, characterized in that it further comprises: receiving an image data signal; and setting the state of each of the first and second elements of the luminous screen on the basis, at least in part, of the image data signal.
17. The method according to claim 12, characterized in that it further comprises: generating a third pulse of a third parameter value that is greater than the response threshold of a third element of the luminous screen, where the third value is less than the response threshold that the first and second element of the luminous screen; and applying the third pulse to the plurality of elements of the luminous screen.
18. 18. The method according to claim 12, characterized in that the application of the first pulse to the plurality of elements of the luminous screen comprises applying the first pulse to the plurality of interferometric levelers.
19. 19. The method according to claim 12, characterized in that the plurality of elements of the luminous screen is characterized by respective resistance-capacitor (RC) time constants.
20. 20. The method according to claim 19, characterized in that the respective response times of the plurality of elements of the luminous screen is based, at least in part, on the respective RC time constants, and where the first and second elements of the luminous screen are characterized by different RC time constants.
21. The method according to claim 20, characterized in that the plurality of elements of the luminous screen are characterized by respective physical properties.
22. 22. The method according to claim 12, characterized in that the respective response times of the plurality of elements of the luminous screen are based, at least in part, on the respective spring constants, and where the first and second elements of The luminous screen are characterized by different spring constants.
23. The method according to claim 18, characterized in that each of the plurality of interferometric modulators comprises a moving mirror characterized by a respective resistance when moving through the air.
24. The method according to claim 12, characterized in that the respective response times of the plurality of interferometric modulators are based, at least in part, on the respective air resistance of the moving mirror, and where the first and second elements of the luminous screen are characterized by different resistances to the movement through the air.
25. 25. The method according to claim 12, characterized in that the application of the first pulse to the plurality of elements to the luminous screen comprises applying the first pulse to a pixel of a visual luminous screen.
26. 26. The method according to claim 25, characterized in that the pixel comprises the plurality of elements of the luminous screen.
27. 27. The method according to claim 12, characterized in that the application of the pulse to the plurality of elements of the luminous screen comprises applying a voltage impulse.
28. The method according to claim 12, characterized in that the application of the first pulse to the plurality of elements of the luminous screen comprises applying a first voltage pulse to a row of the elements of the luminous screen and applying a second pulse of voltage to a column of the elements of the luminous screen, and each of the first and second element of the luminous screen is associated with the row and the column. -
29. 29. A luminous screen, characterized in that it comprises: a plurality of display means arranged in rows, where the display means of each of the rows are further arranged in sub-rows and where the sub-rows of each row are electrically connected; and a plurality of means for resisting the electric current, each of the resistance means connected to a respective one of the sub-rows, the respective means of resistance of each of the sub-rows of each row having a resistance different from that of the resistance means connected to the other sub-rows of the row.
30. 30. The luminous screen according to claim 29, characterized in that at least one of the resistance means comprises a resistance.
31. 31. The luminous screen according to claim 29 or 30, characterized in that at least one of the display means comprises an interferometric modulator.
32. The device according to claim 29, characterized in that it additionally comprises: a processor that is in electrical communication with the display means, the processor being configured to process image data; and a memory device in electrical communication with the processor.
33. The device according to claim 32, characterized in that it additionally comprises a controller configured to send at least a portion of the image data to the driver circuit or exciter.
34. 34. The device according to claim 32, characterized in that it additionally comprises an image source module configured to send the image data to the processor.
35. 35. The device according to claim 34, characterized in that the image source module comprises at least one of a receiver, a transceiver and a transmitter.
36. 36. The device according to claim 32, characterized in that it further comprises an input device configured to receive input data and to communicate the input data to the processor.
37. 37. A method for manufacturing a luminous screen, characterized in that it comprises: - providing a plurality of MEMS elements arranged in rows, where the MEMS elements of each of the rows are further arranged in sub-rows and where the sub-rows of each row are electrically connected; and connecting a plurality of resistors to the MEMS elements, each of the resistors connected to one of the respective sub-rows, the respective resistances for each of the sub-rows of each row having a resistance different from that of the resistors connected to the other sub-rows of the row.