KR20070063552A - Method and device for manipulating color in a display - Google Patents

Abstract

A method and device for manipulating color in a display includes a display in which one or more of the pixels includes one or more display elements, such as interferometric modulators, configured to output colored light and one or more display elements configured to output white light. Other embodiments include methods of making such displays. In addition, embodiments include color displays configured to provide a greater proportion of the intensity of output light in green portions of the visible spectrum in order to increase perceived brightness of the display.

Description

METHOD AND DEVICE FOR MANIPULATING COLOR IN A DISPLAY}

FIELD OF THE INVENTION The field of the present invention relates to microelectromechanical systems (MEMS).

Micromechanical systems (MEMS) include micromechanical elements, actuators, and electronic devices. Micromachining devices may be deposited, etched, and / or other micromachining processes that add layers to etch away substrate and / or portions of the deposited material layers or to make electrical and electromechanical devices. It can be prepared using. One form of micromechanical system equipment is an interference modulator. As used herein, an interferometric modulator or interfering optical modulator refers to a device that selectively absorbs or reflects light using the principles of optical interference. In a particular embodiment, the interference modulator includes a pair of conductive plates, one or both of which may be wholly or partially transparent and / or reflective, and may move relatively when an appropriate electrical signal is applied. have. In a particular embodiment, one plate may comprise a pinned layer disposed on a substrate, and the other plate may comprise a metal film spaced apart from the pinned layer by an air gap. As described in more detail herein, one plate position may change the optical interference of light incident on the interference modulator with respect to the position of the other plate. Such devices have a wide range of applications, and utilizing and / or modifying the features of these types of devices so that they can be used to improve existing products and create new products that have not yet been developed. It would be very beneficial in the art.

Each of the systems, methods, and devices of the present invention has several aspects, and one aspect is not solely responsible for its desired characteristics. Without limiting the scope of the invention, its more prominent features will be summarized. After considering this summary, in particular after reading the section entitled "Detailed Description of Certain Embodiments," it will be understood how the features of the present invention provide advantages over other display devices.

One embodiment includes a display. The display includes a plurality of pixels. Each of the pixels comprises one or more red subpixels comprising one or more interference modulators configured to output red light, one or more green subpixels comprising one or more interference modulators configured to output green light, one or more interferences configured to output blue light One or more blue subpixels including a modulator, and one or more white subpixels including one or more interference modulators configured to output color light.

Another embodiment includes a display. The display includes a plurality of interferometric modulators. The plurality of interference modulators include one or more interference modulators configured to output red light, one or more interference modulators configured to output green light, one or more interference modulators configured to output blue light, and one or more interference modulators configured to output white light. . One or more interference modulators configured to output the white light have a standardized white point.

Another embodiment includes a display. The display includes a plurality of display elements. The plurality of display elements include each including a reflective surface configured to be positioned at a distance from the partially reflective surface. The plurality of display elements includes one or more display elements configured to output color light and one or more display elements configured to coherently output white light.

Another embodiment includes a display manufacturing method. The method includes forming a plurality of display elements. Each of the plurality of display elements includes a reflective surface configured to be positioned at a distance from the partially reflective surface. Each said distance is selected such that one or more display elements output color light and at least one of said plurality of display elements coherently outputs white light.

Another embodiment includes image display means. The image display means includes reflecting means for reflecting light and partial reflecting means for partially reflecting light. The reflecting means is configured to be located away from the partial reflecting means. The image display means includes first output means for outputting color light and second output means for coherently outputting white light.

Another embodiment includes a display. The display includes a plurality of pixels, each comprising a red interference modulator, a green interference modulator, and a blue interference modulator configured to output red light, green light, and blue light, respectively. Each said pixel is configured to output green light of intensity stronger than red light and green light of intensity stronger than blue light when each said interference modulator is set to output red light, green light, blue light.

Another embodiment includes a display manufacturing method. The method includes forming a plurality of pixels. The forming of the plurality of pixels includes forming an interference modulator configured to output red light, forming an interference modulator configured to output green light, and forming an interference modulator configured to output blue light. Each said pixel is configured to output green light of intensity stronger than red light and green light of intensity stronger than blue light when each said interference modulator is set to output red light, green light, blue light.

Another embodiment includes a display. The display includes a plurality of pixels. Each said pixel includes a red interference modulator, a green interference modulator, and a blue interference modulator configured to output red light, green light, and blue light, respectively. Each said pixel is configured to output green light of intensity stronger than red light and to output green light of intensity stronger than blue light. At least one of the interference modulator configured to output the red light and the interference modulator configured to output the blue light is configured to output light having a wavelength selected to compensate for the strong intensity of the green light.

Another embodiment includes a display comprising a plurality of red light output means for outputting red light, a plurality of green light output means for outputting green light, and a plurality of blue light output means for outputting blue light. The red light output means, the green light output means, and the blue light output means form pixel display means for displaying an image pixel. Each of the pixel display means is configured to output green light having a stronger intensity than blue light when the red light output means, the green light output means, and the blue light output means are set to output red light, green light and blue light.

Another embodiment includes a display that includes a plurality of display elements. The plurality of display elements includes at least one color display element configured to output color light, and at least one display element configured to output white light, wherein the at least one display element configured to output white light has a standardized white point. Output white light.

Another embodiment comprises a display comprising image display means. The image display means includes color light output means for outputting color light and white light output means for outputting white light. The white light output means outputs white light having a normalized white point.

Another embodiment includes a method of manufacturing a display, the method comprising forming a plurality of display elements, wherein forming the plurality of display elements comprises one or more display elements and white light configured to output color light. Forming one or more display elements configured to output. The one or more display elements configured to output the white light are configured to output white light having a normalized white point.

1 is an isometric view of a portion of one embodiment of an interferometric modulator display with the movable reflective layer of the first interferometric modulator in the release position and the movable reflective layer of the second interferometric modulator in the operating position.

2 is a system block diagram illustrating one embodiment of an electronic device including a 3x3 interference modulator display.

3 is a diagram illustrating the position of a movable mirror corresponding to an applied voltage in one embodiment of the interference modulator of FIG.

4 illustrates a set of horizontal and vertical voltages that can be used to drive an interferometric modulator display.

FIG. 5A is a diagram illustrating an exemplary frame for display data in the 3x3 interferometric modulator display of FIG. 2.

FIG. 5B is an exemplary timeline for the horizontal and vertical column signals that may be used to record the frame of FIG. 5A.

6A and 6B are system block diagrams illustrating an embodiment of a visual display device including a plurality of interference modulators.

7A is a cross-sectional view of the device of FIG. 1.

7B is a cross-sectional view of another embodiment of an interference modulator.

7C is a cross-sectional view of another embodiment of an interference modulator.

7D is a cross-sectional view of another embodiment of an interference modulator.

7E is a cross-sectional view of yet another embodiment of an interference modulator.

8 is a side cross-sectional view of an exemplary interference modulator that exhibits spectral characteristics of output light by positioning a mirror that is movable in a range of positions.

9 is a graphical diagram illustrating an spectral response of one embodiment that includes a cyan interference modulator and a yellow interference modulator to produce white light.

10 is a side cross-sectional view of an interferometric modulator showing different optical paths through a modulator through which different color light is reflected.

11 is a side cross-sectional view of an interference modulator with a layer of material that selectively transmits light of a particular color.

12 is a graphical diagram illustrating an spectral response of one embodiment that includes a green interference modulator and a "magenta" filter layer to produce white light.

13 is a schematic diagram illustrating two pixels in an exemplary pixel array 30 in which horizontal columns 1-4 and vertical columns 1-4 form one pixel 120a.

FIG. 14A is a chromaticity diagram illustrating colors that may be produced by an example color display comprising a red display element, a green display element, and a blue display element.

14B is a chromaticity diagram illustrating colors that may be produced by an example color display including a red display element, a green display element, a blue display element, and a white display element.

The following detailed description relates to specific embodiments of the present invention. However, the present invention can be implemented in many different ways and ways. In the following description, reference is made to the drawings, wherein like numerals are used for like parts throughout the figures. As will be apparent from the description below, the present invention may be implemented on any device as long as it is configured to display images, whether moving pictures (eg video) or still pictures (eg still images), or text or pictures. More specifically, the present invention is not limited to, for example, mobile phones, wireless devices, personal digital assistants (PDAs), portable computers or portable computers, GPS receivers / navigators, cameras, MP3 players, Camcorders, game consoles, wristwatches, watches, calculators, television monitors, flat panel displays, computer monitors, car displays (eg odometer display), cockpit controls and / or displays, displays of surveillance cameras (eg rear in cars) Display of surveillance cameras), electronic picture frames, electronic bulletin boards or electronic indicators, projectors, building structures, packages, and aesthetic structures (e.g., image displays on jewelry) and the like. In addition, a device having a structure similar to the microelectromechanical system device disclosed herein may be used in non-display fields such as electronic switching devices.

One embodiment is a display where each pixel comprises a set of display elements and each display element comprises one or more interference modulators. The set of display elements includes display elements configured to output red, green, blue and white light. In one embodiment, the "white light" display element outputs white light having a broader and stronger spectral response than the combined spectral response of the "red", "green" and "blue" display elements. In one embodiment, the display includes drive circuitry configured to turn on the “white light” display element when the data drives the pixel. The embodiment also provides a higher ratio of the output light intensity of the green portion of the visible spectrum to increase the visibility of the brightness of the display.

One embodiment of an interferometric modulator display including an interferometer microelectromechanical system display element is shown in FIG. 1. In such a device, the pixel is in either a bright state or a dark state. In the bright state (“on state” or “open state”), the display element reflects most of the visible light incident to the user. In the dark state (“off state” or “closed state”), the display element reflects little incident visible light to the user. Depending on the embodiment, the light reflection characteristics of the "on state" and the "off state" may be reversed. The microelectromechanical system pixels can be configured to prominently reflect the selected color to enable color display as well as black and white.

1 is an isometric view of two adjacent pixels in a series of pixels of an image display. Here, each pixel comprises an interference modulator of a microvoltaic system. In some embodiments, the interferometric modulator display comprises a matrix array of these interferometric modulators. Each interference modulator includes a pair of reflective layers disposed at variable and controllable distances from each other to form at least one dimensionally variable resonant optical cavity. In one embodiment, one of these reflective layers can be moved between two positions. In the first position (herein referred to as the "released state"), the movable layer is located relatively far from the partially reflective fixed layer. In the second position, the movable layer is located closer to the partially reflecting layer. Incident light reflected from the two layers interferes constructively or destructively depending on the position of the movable reflective layer, making each pixel totally reflective or non-reflective.

The pixel array of the portion shown in FIG. 1 includes two adjacent interference modulators 12a and 12b. In the interferometric modulator 12a on the left, it is shown that the movable reflective layer 14a is in the release position at a predetermined distance from the optical stack 16a including the partial reflective layer. In the interferometric modulator 12b on the right, the movable reflective layer 14b is shown in an operating position adjacent to the optical stack 16b.

Optical stacks 16a and 16b (collectively referred to as optical stack 16) are typically several fused layers that may include an electrode layer, such as indium tin oxide (ITO), as mentioned herein. ), A partially reflective layer, such as chromium, and a transparent dielectric. Therefore, the optical stack 16 is electrically conductive, partially transparent, and partially reflective, and can be produced, for example, by depositing one or more of the above layers onto the transparent substrate 20. In some embodiments, the layers may be patterned in parallel strips to form a row electrode of a display device as described in detail below. The movable layers 14a, 14b are a series of parallel strips (horizontal columns electrodes 16a, 16b) made of metal layer (s) deposited on top of the posts 18 and the surface of the sacrificial material interposed between the posts. Perpendicular to)). Etching and removing the sacrificial material, the movable reflective layers 14a and 14b are spaced apart from the optical stacks 16a and 16b by the gaps 19 formed. The reflective layer 14 may be formed using a material having high conductivity and reflectivity, such as aluminum, and these strips may form a column electrode of a display device.

If no voltage is applied, the cavity 19 remains between the movable reflective layer 14a and the optical stack 16a, and the movable layer 14a is shown by the pixel 12a of FIG. Mechanically released. However, when the potential difference is applied to the selected rows and columns, the capacitor formed at the intersection of the horizontal and vertical electrodes in the corresponding pixel is charged, and the electrostatic force pulls these electrodes together. If the voltage is high enough, the movable reflective layer 14 is deformed and forced against the optical stack 16. The dielectric layer (not shown in this figure) in the optical stack 16 can prevent short circuits and control the separation distance between layers 14 and 16, such as pixel 12b shown on the right in FIG. This aspect is the same regardless of the polarity of the applied potential difference. In this way, horizontal / vertical column driving, which can control the pixel state of reflections and antireflections, is similar in many ways to that used in conventional liquid crystal displays or other display technologies.

2-5 illustrate one exemplary process and system using an array of interferometric modulators in display applications.

2 is a system block diagram illustrating an embodiment of an electronic device that may include various aspects of the present disclosure. In this embodiment, the electronic device includes a processor 21. The processor (21) is a general purpose single-chip or multi-chip microprocessor such as ARM, Pentium®, Pentium II®, Pentium II®, Pentium IV®, Pentium®Pro, 8051, MIPS®, Power PC®, ALPHA®, Or a special purpose microprocessor such as a digital signal processor, microcontroller, programmable gate array, or the like. As known in the art, the processor 21 may be configured to execute one or more software modules. In addition to executing the operating system, the processor may be configured to execute one or more software applications, including a web browser, telephone application, email program, or any other software application.

In one embodiment, the processor 21 is also configured to communicate with the array controller 22. In one embodiment, array controller 22 includes a horizontal column drive circuit 24 and a vertical column drive circuit 26 that provide signals to the display array or panel 30. 2 is a cross-sectional view of the array cut along the line 1-1 in FIG. 1. The horizontal / vertical sequence driving protocol for the interference modulator of the micro-electromotive system may use the hysteresis characteristics of the device shown in FIG. 3. In order to deform the movable layer from the released state to the operating state, for example, a potential difference of 10 volts may be required. However, when the voltage decreases from that value, the movable layer remains intact even if the voltage drops below 10 volts. In the embodiment of Figure 3, the movable layer is not completely released until the voltage drops below 2 volts. Thus, there is a range of voltages in which there is an applied voltage region in which the device is stabilized in either the released or operating state. In FIG. 3 about 3-7 volts is illustrated. This is referred to herein as a "hysteresis region" or "stable region". In the display array with the hysteresis characteristic of FIG. 3, the horizontal / vertical column driving protocol must be operated among the pixels in the horizontal column to which the strobe is applied while the row strobe is applied. The pixels to be exposed to and to be released can be designed to be exposed to a potential difference close to zero (0) volts. After the strobe is applied, a steady state voltage difference of about 5 volts is applied so that the pixels remain in that state whatever the horizontal strobe is. After being written, each pixel has a potential difference in the "stable area" which is 3-7 volts in this embodiment. Due to this configuration, the pixel structure shown in Fig. 1 is stabilized to an existing state, whether operating or released, under the conditions of the same applied voltage. Whether in operating or releasing state, since each pixel of the interferometric modulator is essentially a capacitor formed by a fixed reflective layer and a moving reflective layer, this stable state can be maintained with little power wasted at the voltage in the hysteresis region. If the applied potential is fixed, no current flows into the pixel necessarily.

In a typical application, a display frame can be made by asserting a set of vertical electrodes in accordance with a predetermined set of activated pixels in the first horizontal row. A horizontal pulse is then applied to the electrodes of horizontal column 1 to actuate the pixels corresponding to the asserted vertical column line. Then, the asserted set of vertical electrodes is changed to correspond to a predetermined set of activated pixels in the second horizontal column. A pulse is then applied to the electrodes in horizontal column 2 to actuate the corresponding pixels in horizontal column 2 according to the asserted vertical column electrodes. The pixels in horizontal column 1 are not affected by the pulses in horizontal column 2, and remain in the state set by the pulses in horizontal column 1. Such an operation may be sequentially repeated for the entire horizontal column to generate a frame. In general, these frames are refreshed and / or updated with new display data by continuously repeating this process for a predetermined number of frames per second. Many different protocols for driving horizontal and vertical electrodes to generate display frames are well known and can be used in connection with the present invention.

4, 5A, and 5B illustrate one driving protocol capable of generating display frames in the 3x3 array of FIG. FIG. 4 shows a set of possible voltage levels of vertical and horizontal columns that can be used for the pixels showing the hysteresis curve of FIG. 3. In the embodiment of Fig. 4, to operate the pixel, the corresponding vertical column is set to -V _bias and the corresponding horizontal column is set to + ΔV. Each voltage may correspond to -5 volts and +5 volts. To free the pixel, set the corresponding vertical column to + V _bias and the corresponding horizontal column to + ΔV of the same value so that the potential difference across the pixel is zero volts. In a horizontal column where the voltage of the horizontal column is 0 (zero) volts, the pixels settle to their original state regardless of whether the vertical column is a + V _bias or a -V _bias . As shown in Fig. 4, a voltage of opposite polarity to that described above can be used, for example, by setting an appropriate vertical column to + V _bias and an appropriate horizontal column to -ΔV to improve pixel operation. I can understand that. In this embodiment, the liberation of the pixel can be performed by setting an appropriate vertical column at -V _bias and an appropriate horizontal column at the same-DELTA V to generate a zero (zero) volt potential difference across the pixel.

FIG. 5B is a timing diagram showing a series of horizontal and vertical signals applied to the 3 × 3 array of FIG. 2, resulting in the display arrangement shown in FIG. 5A in which the operated pixels are non-reflective. Before recording the frame shown in Fig. 5A, the pixels may be in any state. In this example, all horizontal rows are zero volts and all vertical rows are +5 volts. With this applied voltage, all the pixels are stable in their existing operating or released state.

In the frame of Fig. 5A, the pixels of (1,1), (1,2), (2,2), (3,2) and (3,3) are operated. To implement this, during the "line time" for horizontal column 1, vertical columns 1 and 2 are set to -5 volts, and vertical column 3 is set to +5 volts. This does not change the state of any pixel. Because all the pixels are within 3-7 volts of stability. Then apply a strobe with a pulse that goes from 0 volts to 5 volts and then goes back to 0 volts in horizontal row 1. This activates the pixels of (1,1) and (1,2) and frees the pixels of (1,3). The other pixels of the array are not affected. To set horizontal row 2 as desired, set vertical row 2 to -5 volts, and vertical rows 1 and 3 to +5 volts. Applying the same strobe to horizontal column 2, the pixels of (2, 2) are activated, and the pixels of (2, 1) and (2, 3) are released. Still, other pixels of the array are not affected. By setting vertical columns 2 and 3 to -5 volts and vertical column 1 to +5 volts, horizontal column 3 can also be set in the same manner. Due to the strobe for horizontal column 3, the pixels in horizontal column 3 are also set as shown in FIG. 5A. After recording the frame, the horizontal column potential remains at 0 (zero) and the vertical column potential remains at +5 volts or -5 volts, so that the display is stabilized in the arrangement of FIG. 5A. It will be appreciated that the same processing can be done for arrays of tens or hundreds of horizontal and vertical columns. In addition, the timing, order, and level of the voltages used for driving the horizontal and vertical columns may be variously changed within the general principles described above, and the above-described examples are merely illustrative, and any driving voltage method is described herein. The present invention may be applied to the systems and methods described above.

6A and 6B are system block diagrams illustrating embodiments of the display device 40. The display device 40 may be, for example, a mobile phone. However, the same components as the display device 40 or a slight modification, such as a television or a portable media player, are examples of various types of display devices.

The display device 40 includes a housing 41, a display 30, an antenna 43, a speaker 45, an input device 48, and a microphone 46. The housing 41 may generally be manufactured by any of a variety of manufacturing processes well known in the art, including injection molding or vacuum molding. In addition, the housing 41 may be made of any of a variety of materials, including but not limited to plastic, metal, glass, rubber, and ceramic or combinations thereof. In one embodiment, the housing 41 includes a detachable portion (not shown), which can be replaced with another detachable portion having a different color or different logo, picture or symbol.

The display 30 of the display device 40 of this example may be any of various displays, including the bi-stable display disclosed herein. In other embodiments, the display 30 may be a flat panel display, such as a plasma, EL, OLED, STN LCD, or TFT LCD, as described above, and a CRT or other tube display, as is well known to those skilled in the art. Non-flat display, such as appliance. However, to illustrate this embodiment, display 30 includes an interferometric modulator display as described herein.

Components in one embodiment of the illustrated display device 40 are schematically illustrated in FIG. 6B. The display device 40 of the illustrated example includes a housing 41 and may further include components that are at least partially disposed within the housing. For example, in one embodiment, the display device 40 of the present example may include a network interface 27 including an antenna 43 connected to the transceiver 47. The transceiver 47 is connected to the processor 21, and the processor 21 is connected to conditioning hardware 52. Conditioning hardware 2052 may be configured to smooth the signal (eg, filter the signal). The conditioning hardware 52 is connected to the speaker 2045 and the microphone 2046. The processor 2021 is also connected to the input device 48 and the driver controller 29. The driver controller 29 is connected to the frame buffer 28 and the array driver 22, and the array driver is connected to the display array 30. The power supply 50 supplies power to all components required in accordance with the particular design of the illustrated display device 40.

The network interface 27 includes an antenna 43 and a transceiver 47 so that the illustrated display device 40 can communicate with one or more devices over a network. In one embodiment, network interface 27 may have some processing power to relieve the burden on processor 21. The antenna 43 transmits and receives a signal, and may be any antenna known to those skilled in the art. In one embodiment, the antenna transmits and receives RF signals in accordance with the IEEE802.11 standard, including IEEE 802.11 (a), (b), or (g). In another embodiment, the antenna transmits and receives RF signals in accordance with Bluetooth standards. In the case of a cellular phone, the antenna is designed to receive CDMA, GSM, AMPS or other known signals used for communication over a wireless cellular network. The transceiver 47 preprocesses the signal received from the antenna 43 so that the processor 2021 can receive and process it. In addition, the transceiver 47 processes the signal received from the processor 21 to be transmitted from the display device 40 of this example through the antenna 43.

In another embodiment, the transceiver 47 may be replaced by a receiver. In another embodiment, the network interface 27 may be replaced with an image source capable of storing or generating image data to be sent to the processor 21. For example, the image source may be a DVD or hard disk drive containing the image data, or may be a software module for generating the image data.

The processor 21 generally controls the overall operation of the display device 40 of this example. The processor 21 receives compressed image data or the like from the network interface 27 or an image source, and processes the image data into a format that can be processed into the original image data or the original image data. Processor 21 then sends the processed data to driver controller 29 or frame buffer 28 for storage. Typically, the original data refers to information indicative of the image characteristics for each location in the image. For example, such image characteristics may include color, saturation (saturation), lightness (gray scale level).

In one embodiment, processor 21 includes a microcontroller, a CPU, or a logic unit that controls the operation of the illustrated display device 40. In general, conditioning hardware 52 includes an amplifier and a filter to send signals to and receive signals from speaker 45. The conditioning hardware 52 may be a separate component within the illustrated display device 40 or may be integrated within the processor 21 or other components.

The driver controller 29 receives the original image data generated by the processor 21 directly from the processor 21 or from the frame buffer 28 and in a format suitable for high speed transfer to the array driver 22. Reconstruct Specifically, the driver controller 29 reconstructs the original image data into a data flow having a format such as a raster so as to have a time sequence suitable for scanning across the display array 30. The driver controller 29 then sends the reconstructed information to the array driver 22. Often a driver controller 29, such as a controller of a liquid crystal display, is integrated with the system processor 21 as a stand-alone IC, but such a controller can be implemented in a number of ways. Such a controller may be embedded in the processor 21 as hardware, or may be fully integrated into hardware with the array driver 22.

Typically, the array driver 22 receives the reconstructed information from the driver controller 29 and applies this video data several times per second to the hundreds and sometimes thousands of leads leading from the pixels of the display's xy matrix. Convert to a waveform set.

In one embodiment, driver controller 29, array driver 22, and display array 30 are suitable for any type of display described herein. For example, in one embodiment, driver controller 29 is a conventional display controller or bistable display controller (eg, an interferometric modulator controller). In another embodiment, the array driver 22 is a conventional driver or bistable display driver (eg, interferometric modulator display). In one embodiment, the driver controller 29 is integrated with the array driver 22. Such examples are common in highly integrated systems such as cell phones, watches and other small displays. In another embodiment, display array 30 is a typical display array or bistable display array (eg, a display that includes an interferometric modulator array).

The input device 48 allows a user to control the operation of the illustrated display device 40. In one embodiment, the input device 48 includes keypads, buttons, switches, touch screens, pressure or thermal sensing membranes, such as a QWERTY keyboard or telephone keypad. In one embodiment, the microphone 46 is the input device of the illustrated display device 40. In the case where the microphone 46 is used to input data to the device, the user may provide a voice command to control the operation of the illustrated display device 40.

The power supply 50 may include various energy storage devices that are well known in the art. For example, in one embodiment, the power source 50 is a rechargeable battery, such as a nickel-cadmium battery or a lithium-ion battery. In another embodiment, the power supply 50 is a renewable energy source, capacitor, or solar cell comprising a plastic solar cell and a solar cell paint. In another embodiment, the power source 50 is configured to receive power from an outlet.

In some implementations, as described above, it is possible to programmatically configure the control of a driver controller that can be located in various places within the electronic display system. In some cases, control of the array driver 2022 may be programmable. Those skilled in the art will recognize that the optimization state described above may be implemented with any number of hardware and / or software components, and may be implemented in a variety of different configurations.

The details of interferometric modulators operating in accordance with the principles described above can vary widely. For example, FIGS. 7A-7E illustrate five different embodiments of the movable reflective layer 14 and the structure supporting it. FIG. 7A is a cross-sectional view of the embodiment of FIG. 1, in which a strip of metal material 14 is deposited on a vertically extending support 18. In FIG. 7B, the movable reflective layer 14 is attached to a tether 32 so that only the edges are supported. In FIG. 7C, the movable reflective layer 14 is suspended from a deformable layer 34 comprising a flexible metal. The deformable layer 34 is directly or indirectly connected to the substrate 20 around the deformable layer 34. This connection is referred to herein as a support post. In the embodiment shown in FIG. 7D, a support post plug 42 is shown on which the deformable layer 34 is placed. The movable reflective layer 14 is in a suspended state in the cavity as shown in FIGS. 7A-7C, but the deformable layer 34 is supported by filling the hole between itself and the optical stack 16. Do not form a post. Rather, the support posts are formed of a planarization material, which is used to form the support post plug 42. Although the embodiment shown in FIG. 7E is based on the embodiment shown in FIG. 7D, it can be applied to any of the embodiments shown in FIGS. 7A-7C as well as additional embodiments not shown. In the embodiment shown in FIG. 7E, an extra layer of metal or other conductive material has been used to form the bus structure 44. This allows signals to be routed behind the interferometric modulator, eliminating the need for a large number of electrodes that had to be formed on the substrate 20.

In an embodiment such as that shown in FIG. 7, the interferometric modulator functions as a direct-view device, in which an image is seen from the front side of the transparent substrate 20 and the interferometric modulator is arranged opposite. It is a structure. In this embodiment, including the deformable layer 34 and the bus structure 44, the reflective layer 14 optically shields portions of the interferometric modulator on the side of the reflective layer opposite the substrate 20. By this, the shielded area can be constructed and operated without adversely affecting the image quality. This distinguishable modulator architecture allows the materials used in the structural and electromagnetic and optical aspects of the modulator to be selected and function independently of each other. In addition, the embodiments shown in FIGS. 7C-7E have the additional benefit of separating the optical properties of the reflective layer 14 from its mechanical properties performed by the deformable layer 34. Thereby, the structural design and the material used for the reflective layer 14 can be optimized with respect to the optical properties, and the material used for the structural design and the deformable layer 34 with respect to the desired mechanical properties. can do.

As described above with reference to FIG. 1, the modulator 12 (ie, modulators 12a and 12b) comprises a mirror 14 (ie, mirrors 14a and 14b) and a mirror 16 (mirror 16a and 16b)) between the optical cavity formed. The characteristic distance of the optical cavity, or the effective optical path length, d is determined by the resonant wavelength of the interference modulator 12, λ, of the optical cavity. The resonant visible wavelength, λ, of the interference modulator 12 generally corresponds to the perceived color of the light reflected by the modulator 12. Mathematically, the optical path length d is 1 / 2Nλ, where N is an integer. The given resonant wavelength λ is reflected by the interference modulator 12 with 1 / 2λ (N = 1), λ (N = 1), 2 / 3λ (N = 1), and so on. The integer N can be referred to as the interference order of the reflected light. As used herein, the order of the modulator 12 also represents the order N of light reflected by the modulator 12 when the mirror 14 is in at least one position. For example, the primary red interference modulator 12 has an optical path length d of about 325 nm, corresponding to a wavelength λ of about 650 nm. Thus, the secondary red interference modulator 12 has an optical path length d of about 650 nm. In general, higher orders of modulator 12 reflect light in a narrower wavelength range, for example, higher " Q " values produce more saturated color light. Saturation of modulator 12 including color pixels affects the display's properties, such as the color gamut and white point of the display. For example, the secondary modulator 12 is different so that the display using the secondary modulator 12 has the same white point or color balance as the display including the primary modulator that reflects the same general color of light. It may be chosen to have a center peak optical wavelength.

8 is a side cross-sectional view of an exemplary interference modulator 12 that exhibits the spectral characteristics of the light to be output by placing the movable mirror 14 in the range of positions 61-65. Exemplary modulators include a conductive layer 52 of indium-tin-oxide (ITO) that acts as a vertical column electrode. In the exemplary modulator, the movable mirror 14 includes a horizontal column conductor.

Each particular group of positions 61-65 of the movable mirror 14 is indicated by an arrow extending from the fixed mirror 16. The point of each arrow represents a particular one of the positions 61-65 of the movable mirror. The color of the light reflected from the interferometric modulator is determined by the optical path length d between the movable mirror 14 and the fixed mirror 16. The distances 61-65 are chosen to take into account the thickness and reflectance of the insulating layer 54 at the optical path length d. Thus, the movable mirror 14 located at different ones of the positions 61-65, respectively corresponding to different distances d, outputs light at the viewing position 51 having different spectral responses. Will be a modulator 12, the different spectral responses corresponding to different colors of incident light reflected by the modulator 12. In addition, at position 61, the movable mirror 14 is located very close to the fixed mirror 16, so that the effects of the interference can be neglected, and the modulator 12 substantially equals all of the visible incident light as white light. It acts as a mirror that substantially reflects color. The small distance d is too small for the optical response in the visible band, causing a wideband mirror effect. Thus, the mirror 14 only acts as a reflective surface with respect to visible light.

By means of the mirror 14 located at position 62, the modulator 12 has several shades of different brightness, since the increased gap distance between the mirrors 14 and 16 reduces the reflectivity of the mirror 14. of gray). At position 63, because the resonant wavelength is outside the visible range, there is a distance d such that the cavity operates coherently but does not substantially reflect the visible wavelength of light at all.

As the distance d increases further, the peak spectral response of the modulator 12 shifts to the visible wavelength. Therefore, when the movable mirror 14 is in position 64, the modulator 12 reflects blue light. When the movable mirror 14 is in position 65, the modulator 12 reflects green light. When the movable mirror 14 is in the non-deflected position 66, the modulator 12 reflects red light.

When designing the display using the interference modulator 12, the modulator 12 is formed to increase the color saturation of the reflected light. Saturation means the intensity of the hue of the color light. Highly saturated tones represent vibrant and intense colors, while lowly saturated tones represent more faded grays. For example, lasers that produce a very narrow range of wavelengths produce highly saturated light. Conversely, conventional incandescent bulbs produce white light with a red or blue color that is less saturated. In one embodiment, the modulator 12 is formed at a distance d corresponding to a higher interference order, for example a second or third order, to increase the saturation of the reflected color light.

Exemplary color displays include red display elements, green display elements, and blue display elements. Different colors are produced in such displays by varying the relative intensities of the light produced by the red, green, and blue display elements. Mixing of the primary primary colors such as red, green and blue is perceived by the human eye as different colors. The relative values of red, green and blue in such a color system are called tristimulus values with respect to the stimuli of the red light, green light and blue light detector of the human eye. In general, the more saturated the primary primary is, the wider the range of colors that can be produced by the display. In another embodiment, the display includes a modulator 12 having a color set that defines a different color system with respect to a set of primary primary colors different from red, green, and blue.

Another conceivable in the design of integrating the display with the interference modulator 12 is the generation of white light. "White" light generally refers to light that is perceived by the human eye without including a particular color, ie white light is not related to color tone. Black refers to the absence of color (or light), while white refers to light that covers a wide spectral range such that no particular color is perceived. White refers to light having a substantially constant intensity over a broad spectral range of visible light. However, since the human eye is sensitive to certain wavelengths of red, green, and blue light, white can be produced by mixing the intensities of the colored light to produce light having one or more spectral peaks perceived as "white" to the human eye. The color range of the display is the range of colors that the device can generate by mixing red light, green light, and blue light, for example.

In reflective displays, white light generated using saturated interferometric modulators tends to have a relatively low intensity for the viewer because only a small range of incident wavelengths is reflected at a relatively high intensity to form white light. In contrast, mirror reflected broadband white light, for example substantially all incident wavelengths, has a high intensity because a broader range of incident wavelengths is reflected. Therefore, as a reflective display is designed using a combination of primary primaries to produce white light, there is a tradeoff between color saturation, color range, and the brightness of the white light output by the display. .

In one embodiment, the movable mirror 14 is such that the modulator 12 is non-reflective of visible light at the first position (eg, position 63 in FIG. 8) and the mirror is movable at the second position. The distance between the 14 and the fixed mirror 16 is too short for interference modulation of incident visible light so that the mirror 14 reflects broadband white (e.g., position 61 in FIG. 8). In this embodiment, the movable mirror 14 reflects incident light with a wide, relatively constant spectral response over the visible spectrum. If the incident light includes white light, the light reflected by the modulator 12 at the second position may be substantially similar white light. The spectral response of this "white" reflection state of modulator 12 may generally be constant throughout the visible spectrum. In one embodiment the spectral response is tuned by the choice of material of the modulator. For example, different materials, such as aluminum or copper, may be used on the reflective surface of the mirror 14 that is movable such that the spectral response of the modulator 12 is tuned when in a white reflective state. In other embodiments, filters may be used to selectively absorb specific wavelengths of reflected or incident light to affect the output of such broadband white modulators.

In one embodiment of pixel array 30, each pixel has one or more modulators 12, for example, modulators configured to reflect red light, green light, blue light, and one or more "white" modulators 12 configured to modulate white light. It includes. In this embodiment, the light from the red modulator, green modulator, and / or blue modulator 12 in each state is combined to output color light. Light from the white modulator 12 can be used to output white light or gray light. Using white in combination with color increases the luminance or intensity of the pixel.

The white point of the display is generally the hue considered to be neutral (grey or colorless). The white point of the display device may be characterized based on the comparison of the spectral content of the white light produced by the display device with the light emitted by the black body at a particular temperature. Black body radiators are ideal objects that absorb all the light incident on the object and re-emit light whose spectrum depends on the temperature of the black body. For example, the black body spectrum at 6,500 ° K is referred to as white light with a color temperature of 6,500 ° K. This color temperature, or white point of approximately 5,000-10,000 degrees K, is generally recognized in daylight.

The International Commission on Illumination (CIE) sets the standardized white point of the light source. For example, the light source designation of "d" represents day. In particular, the standard white points D ₅₅ , D ₆₅ , D ₇₅ that correlate with color temperatures of 5,500 ° K, 6,500 ° K, and 7,500 ° K are standard day white points.

The display device can be characterized by the white point of the white light generated by the display. In accordance with light from another light source, the human perception of the display is determined at least in part by the recognition of light from the display. For example, a display or light source having a low white point, for example D55, may be perceived by the viewer as having a yellow tone. A display with a higher temperature white point, for example D75, may be perceived by the user as having a "cold" or bluer tone. Users generally respond more favorably to displays with higher temperature white points. Therefore, controlling the white point of the display gives the display control over the viewer's response. Embodiments of the interferometric modulator array 30 may be configured to produce white light where the white point is selected to match a normalized white point, under one or more expected lightening conditions.

White light may be selected by the pixel array 30 by including one or more interference modulators 12 per pixel. For example, in one embodiment, pixel array 30 includes pixel groups of red interference modulator, green interference modulator, blue interference modulator 12. As described above, the color of the interferometric modulator 12 can be selected by selecting the optical path length d using the relationship d = 1 / 2Nλ. In addition, the balance or relative ratio of the colors produced by each pixel of the pixel array 30 may also be relative to each of the interference modulators 12, eg, the red interference modulator, the green interference modulator, the blue interference modulator 12. May be further affected by the reflective area. In addition, since the modulator 12 selectively reflects incident light, the white point of the ball reflected from the pixel array 30 of the interference modulator 12 generally depends on the spectral characteristics of the incident light. In one embodiment, the white point of reflected light may be configured to be different from the white point of incident light. For example, in one embodiment, pixel array 30 may be configured to reflect D75 when used in D65 sunlight.

In one embodiment, the distance d and the area of the interferometric modulator 12 of the pixel array 30 are fluorescent in the lightening conditions where the white light generated by the pixel array 30 is expected, for example during daylight. light) or from front light that is determined to irradiate pixel array 30, it is selected to correspond to a specially standardized white point. For example, the white point of pixel array 30 is selected to be D ₅₅ , D ₆₅ , D ₇₅ in a particular lightening condition. In addition, the light reflected by the pixel array 30 may have a different white point than the light of the predicted or configured light source. For example, certain pixel arrays 30 may be configured to reflect D75 light when viewed under D65 daylight. More generally, the white point of the display may be selected with respect to an illumination source configured with the display, eg front light, or with particular viewing conditions. For example, the display may be configured to have selected white points, for example D55, D65, D75, when viewed under a predicted or conventional illumination source such as an incandescent light source, a fluorescent light source, or a natural light source. In particular, a display, for example for use in a portable device, may be configured to have a selected white point when viewed under daylight conditions. Alternatively, the display for use in an office environment may be configured to have a selected white point, for example D75, when illuminated by conventional office fluorescent light. In various embodiments, other distances d and areas of modulator 12 may be selected to produce other standardized white points that are set in different viewing environments. In addition, the red modulator, green modulator, blue modulator 12 may also be placed in the reflected or non-reflective state for different times to further vary the reflected red light, green light, relative balance of blue light, and white points of the reflected light. Can be controlled. In one embodiment, the ratio of the reflective areas of each color modulator 12 may be selected to control the white point in different viewing environments. In one embodiment, the optical path length d is selected to correspond to the common multiple of one or more visible resonant wavelengths, e.g., red, green, blue first, second, third order peaks, so that interference modulator 12 is It reflects white light characterized by three visible peaks in its spectral response. In this embodiment, the optical path length d may be selected such that the generated white light corresponds to a normalized white point.

In addition to the group of red, green, and blue interference modulators 12 of the pixel array 30, other embodiments include other ways of generating white light. For example, one embodiment of pixel array 30 includes an interference modulator 12 that includes each individual distance d to produce a cyan interference modulator and a yellow interference modulator, for example cyan and yellow light. . The cyan interference modulator and the yellow interference modulator 12 produce light with a wideband spectral response that is perceived as "white." The cyan interference modulator and the yellow interference modulator are approximately positioned so that the viewer recognizes this combined response. For example, in one embodiment, the cyan interference modulators and the yellow interference modulators are arranged in adjacent horizontal rows of the pixel array 30. In another embodiment, the cyan interference modulator and the yellow interference modulator are arranged in adjacent vertical rows of the pixel array 30.

9 is a graphical diagram illustrating an spectral response of one embodiment that includes a cyan interference modulator and a yellow interference modulator 12 to produce white light. The horizontal axis represents the wavelength of the reflected light. The vertical axis represents the relative reflectance of light incident on the modulator 12. Trace 80 represents the response of the cyan interference modulator, which is a single peak located in the center of the cyan 'part of the spectrum, for example between blue and green. Trace 82 represents the response of the yellow interference modulator, which is a single peak located in the center of the yellow portion of the spectrum, for example between red and green. Trace 84 represents the combined spectral response of a pair of cyan interference modulators and yellow interference modulator 12. Trace 84 has two peaks at the cyan wavelength and the yellow wavelength, but is sufficiently constant throughout the visible spectrum so that the light reflected from these modulators 12 is perceived as white.

In general, the color of light reflected by the interference modulator 12 shifts when the modulator 12 is viewed from different angles. 10 is a cross-sectional side view of an interferometric modulator 12 showing different optical path lengths through the modulator 12. The color of the light reflected from the interferometric modulator 12 varies for different incidence angles (and reflection angles) with respect to the axis AA as shown in FIG. 10. For example, in the interference modulator 10 shown in FIG. 10, when light travels along the off-axis path A1, the light is incident on the interference modulator at a first angle, reflected from the interference modulator and reflected to the viewer. Go to. The viewer perceives the first color when light arrives at the viewer as a result of optical interference between the pair of mirrors in the interference modulator 12. When the viewer changes the viewing angle by moving or changing his position, the light perceived by the viewer moves along another off-axis path A2 corresponding to a second, different angle of incidence (and reflection). Optical interference at the interference modulator 12 depends on the optical length, d, of light propagated in the modulator. Therefore, different optical path lengths for different optical paths A1 and A2 produce different outputs from the interferometric modulator 12. Increasing the viewing angle, the effective optical path of the interferometric modulator decreases according to the relationship 2d cosβ = Nλ, where β is the viewing angle (the angle between the normal and the incident light to the display). As the viewing angle increases, the peak resonance wavelength of the reflected light decreases. Therefore, the user perceives different colors according to his viewing angle. As mentioned above, this phenomenon is referred to as "color shift". This color shift is typically identified in relation to the color produced by the interference modulator 12 when viewed along axis AA.

In one embodiment, pixel array 30 includes a primary yellow interference modulator and a secondary cyan interference modulator. Viewing this pixel array 30 with increasing off-axis angle, the light reflected by the primary yellow interferometric modulator is shifted towards the blue end of the spectrum, i.e., the modulator of the predetermined angle is the primary cyan interferometric modulator. It has an effective distance d equal to the distance of. In conclusion, the light reflected by the secondary cyan interference modulator is shifted to correspond to the light from the primary yellow interference modulator. The overall combined spectral response is therefore wide and relatively constant over the visible spectrum, as is the relative peak of the spectral shift. Therefore, such pixel array 30 generates white light at a relatively wide range of viewing angles.

In one embodiment, a display having a cyan modulator and a yellow modulator may be configured to produce white light having a selected normalized white point, under one or more viewing conditions. For example, the cyan modulator so that the reflected light has a white point of D55, D65, D75, or any other suitable white point under selected irradiation conditions including D55, D65, D75, such as a display suitable for external use. The spectral response of the yellow modulator is selected. In one embodiment, the modulators may be configured to reflect light having a white point different from incident light from the predicted or selected viewing condition.

11 is a cross-sectional side view of an interferometric modulator 12 having a layer of material 102 that selectively transmits light of a particular color. In an exemplary embodiment, the material layer 102 is on the opposite side of the substrate 20 from the interference modulator 12. In one embodiment, the material layer 102 includes a magenta filter in which the green interference modulator 12 is visible. In one embodiment, material layer 102 is a dyed material. In one such embodiment, the material is a dyed photoresist material. In one embodiment, green interference modulator 12 is a primary green interference modulator. The filter layer 102 is configured to transmit magenta light when irradiating a wide constant white light. In an exemplary embodiment, light is incident on layer 20 and light filtered from the layer is transmitted to modulator 12. Modulator 12 reflects the filtered light back through layer 102. In this embodiment, light passes through layer 102 twice. In this embodiment, the thickness of the material layer 102 is selected and utilized to compensate for this dual filtering. In another embodiment, the front light structure is located between layer 102 and modulator 12. In this embodiment, the material layer 102 only acts on the light reflected by the modulator 12. In this embodiment, layer 102 is selected accordingly.

12 is a graphical diagram illustrating the spectral response of one embodiment including a green interference modulator 12 and a “magenta” filter layer 102. The horizontal axis represents the wavelength of the reflected light. The vertical axis represents the relative spectral response of light incident across the visible spectrum over green modulator 12 and filter layer 12. Trace 110 represents the response of the green modulator, which is a single peak located in the center of the green portion of the spectrum, for example in the center of the visible spectrum. Trace 112 represents the response of the magenta filter formed by material layer 102. Trace 112 has two relatively flat portions on one side of the central u-shaped trough. Trace 112 therefore represents the response of the magenta filter to selectively transmit substantially all red and blue light while filtering the light in the green portion of the spectrum. Trace 114 shows the combined spectral response pairing green modulator 12 and filter layer 102. Trace 114 indicates that the spectral combining response is at a lower reflection level than green modulator 12 due to the filtering of light by filter layer 102. However, the spectral response is relatively constant over the visible spectrum so that filtered and reflected light from green modulator 12 and magenta filter layer 102 is perceived as white.

In one embodiment, the display including green modulator 12 with magenta filter layer 102 may be configured to generate white light with a selected normalized white point, under one or more viewing conditions. For example, the reflected light may have a white point of D55, D65, D75, or any other suitable white point under selected irradiation conditions including D55, D65, D75 light, such as daylight for display suitable for external use. The spectral response of green modulator 10 and magenta filter layer 102 is selected. In one embodiment, modulator 12 and filter layer 102 may be configured to reflect light having a white point different from incident light from the predicted or selected viewing conditions.

13 is a schematic diagram illustrating two pixels of an example pixel array 30. The male 1-4 and the vertical column 1-4 form one pixel 102a. The horizontal columns 5-8 and the vertical columns 1-4 form the second pixel 120b. Each pixel 120a and 120b includes at least one modulator 12 configured to reflect red light (vertical string 1), green light (vertical string 2), blue light (vertical string 3), and white light (vertical string 4). . Each pixel of the exemplary pixel array 30 includes four display elements of each of red, green, blue, and white to form “4 bits” per color display, which is red for a total of 2 ¹⁶ shades of color. 2, ⁴ = 16 shades of green, blue, and white may be output.

FIG. 14A is a chromaticity diagram illustrating colors that may be generated by an example color display including a red display element, a green display element, and a blue display element. A wide range of colors is produced in such displays by varying the relative intensities of the light produced by the red, green, and blue display elements. Chromaticity diagrams show how the display can be controlled to be perceived as different colors to the human eye by a mixture of primary colors such as red, green, and blue. The horizontal and vertical axes of FIG. 14 define chromaticity coordinate systems in which color values may appear. In particular, point 130 represents the color of light reflected by the exemplary red interference modulator, the green interference modulator, and the blue interference modulator. Triangular trace 133 surrounds region 134 corresponding to the range of colors that may be generated by mixing the light generated at point 120. This range of colors may be referred to as the color range of the display. In operation, each of the red display element, green display element, and blue display element in the pixel may be controlled to produce different mixtures of red light, green light, and blue light that are combined to form respective colors within the color range.

As shown in FIG. 13, in one embodiment, exemplary display 30 includes pixels having subpixels of red, green, blue, and white. In one embodiment of the manner of driving such a display, (i) red, green, white chromaticity values defining three different color ranges, (ii) red, blue, white chromaticity values, (i) blue, Each pixel is defined to be displayed by the pixel in a combination of chromaticity values of green and white. In operation of this embodiment, when the display controller determines that a particular pixel is set to a color value represented by red, green, or blue, the display controller determines the color value by (i) red, green, white, (ii) red, Converts to a value expressed in relation to one of blue, white, (iii) blue, green, and white.

14B is a chromaticity diagram illustrating the colors that can be produced by such a color display. The entire color range of the display is defined by the area defined by the trace 140, which connects each of the points 130 corresponding to the chromaticity of the display primary color to red, green and blue. Point 130a also corresponds to the chromaticity of the light emitted by the white subpixels. This point 130a may be at other locations that depend on the white produced by the white subpixel. Traces 144a, 144b, and 144c connect points 130a corresponding to the white subpixels to respective points 130 corresponding to red, green, and blue, respectively. In conjunction with trace 140, traces 144a, 144b, and 144c may comprise (i) red, green, and white display elements, (ii) red, blue, and white display elements, and (i) blue, green, and white Three regions 146a, 146b, 146c are defined within the color range of the display corresponding to the colors that can be generated by the display element, respectively. Therefore, conceptually, one embodiment of such a drive scheme for display involves identifying within which of the three areas 146a, 146b, 146c the desired color to be displayed matches. At this time, the input color represented by the red, green, and blue values is converted into a new chromaticity. This chromaticity coordinate will correspond to one of the three areas 146a, 146b, 146c identified. Then, using the new output values, the desired chromaticity coordinates are (i) red, green, and white display elements, (ii) red, blue, and white display elements, and (i) blue, green, and white display elements. Each of the three identified display elements bounding the matching area is driven.

In one embodiment, when there is a chromaticity value within a selected distance (eg, on the chromaticity diagram) of point 130a of the white display element, both the color display element and the white display element are activated to further draw from the pixel for that color. Produces output

In one embodiment, to drive such a pixel array, when the overall hue of the pixel data is less than the threshold, for example when the pixel data is a gray color or near gray color, the drive circuitry selects the white modulators in the vertical column 4. Set to the corresponding reflection state. In one embodiment, the red modulator, green modulator, blue modulator may also be in their respective states. When the overall tonality for the pixel data is above the threshold, for example when the pixel data is almost gray, the driving circuit sets the white modulators in vertical column 4 to non-reflective and the color modulators in vertical columns 1-3. Set them to reflection.

In one embodiment, the white display element can be activated in combination with the color display element to add additional brightness. For example, when a pixel is supposed to output red light, all red display elements within that pixel are activated. In addition, one or more white display elements may also be activated to produce other color combinations.

In certain embodiments, the driving circuit adjusts the input data (even if the display improves its relative brightness) such that the display produces an image with a color balance that is substantially unchanged by the white reflective area. It can compensate for the white surface area of.

In one embodiment, the white interference modulators are grouped into other white interference modulators, as in the extra vertical column shown in FIG. In another embodiment, the white interference modulators are evenly distributed across the interlaced pixels, for example, between the red display element, the green display element, and the blue display element. Further, in some embodiments, the number of white display elements in each pixel is different from the number of red display elements, green display elements, and blue display elements, for example.

In addition to using additional interference modulators configured to reflect white light to increase the intensity of reflected white light, embodiments of pixel array 30 may be constructed that increase the overall apparent brightness of the system by other means. . For example, the human eye is more sensitive to green light than other tones. Therefore, in one embodiment, using an additional green interference modulator per pixel increases the transparent brightness of the interference modulator system. For example, in some embodiments, there is the same number of green interference modulators, red interference modulators, blue interference modulators per pixel. In one embodiment, similar to that shown in FIG. 13, a green interference modulator of a second vertical column may also be included. In another embodiment, pixel array 30 may include a fourth vertical column, as shown in FIG. 13, where some display elements reflect white light and some reflect green light.

In one embodiment, additional green interferometric modulators can be grouped into other green interferometric modulators, such as in an extra vertical column as shown in FIG. 13. In another embodiment, the additional green interference modulator is evenly distributed across the interlaced pixels, for example, between the red display element, the green display element, and the blue display element. Further, in some embodiments, the number of extra green display elements in each pixel may be different from the number of red display elements, green display elements, and blue display elements, for example. In one embodiment, the display element is an interference modulator in which the optical path lengths d of the red and blue modulators compensate for additional green pixels in the color balance of the display. Further, in one embodiment, the optical path length d of one or both of the red and blue display elements can be selected to produce more saturated colors. In one such embodiment, the optical path length d of the red display element or blue display element may be selected to produce higher order (secondary or higher) reflected light. The second order corresponds to the optical path length d equal to 1 × λ. Interferometric modulators with more saturated responses reflect smaller portions of incoming light, and such modulators tend to have less intense (darker) output. However, by increasing the relative intensity of the reflected green light, such a display can be configured to appear brighter to the viewer. In one embodiment, the area ratio of red to blue is one to one while the area of green to red (or blue) is greater than one to one. For example, in one embodiment, if the total reflection area of each pixel is expressed as a percentage, 33-50% of the pixels are green. In one embodiment, 38-44% of the pixels are green.

In one embodiment, the ratio of the surface area of the green interference modulator to the total reflective surface area of the pixels may be greater than the ratio of the surface area of the red and blue interference modulators to increase the perceived brightness. In another embodiment, the period of time during which the green interference modulator is in the reflective state is increased to increase the green color associated with the period of the interference modulator producing other colors. In one embodiment, the blue interference modulator and the red interference modulator are tuned toward the green spectrum to increase the appearance of green and thereby increase the perceived brightness in the system. As will be appreciated by those skilled in the art, the drive circuitry adjusts the input data (even if the display improves its relative brightness) such that the display produces an image with a color balance that is substantially unchanged by the additional green reflective areas. The additional green surface area can be compensated for. In one embodiment, in display modes where luminance is more important than color precision, for example in text displays, an extra green display element is used.

In the foregoing description, the novel features of the invention, which have been applied to various embodiments, have been shown, described, and pointed out, but vary from the detailed construction or form of the apparatus or process illustrated by those skilled in the art without departing from the spirit of the invention. It should be noted that it is possible to omit, replace, and change it. As will be appreciated, some features may be used or realized separately from others, and therefore, the invention may be embodied in a form that does not have all the features and advantages disclosed herein. The scope of the invention is indicated by the appended claims rather than by the foregoing description. Any changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims (83)

Contains a plurality of pixels, Each pixel is One or more red subpixels comprising one or more interference modulators configured to output red light; One or more green subpixels comprising one or more interference modulators configured to output green light; One or more blue subpixels including one or more interference modulators configured to output blue light; And One or more white subpixels including one or more interference modulators configured to output color light Including, display. The method of claim 1, Wherein the display is configured to output white light having a normalized white point. The method of claim 2, And the normalized white point is one of D55, D65, or D75. The method of claim 1, The one or more interference modulators configured to output the color light includes one or more interference modulators configured to output cyan light and one or more interference modulators configured to output yellow light, wherein the cyan light and the yellow light are combined to provide the white light. To generate, display. The method of claim 1, One or more filters associated with one or more interference modulators configured to output the color light, and selectively configured to transmit visible wavelengths associated with magenta light and to substantially filter other visible wavelengths when irradiating white light; , And the one or more interference modulators configured to output the color light comprises one or more interference modulators configured to selectively reflect incident green light. The method of claim 5, And the filter comprises an absorption filter. A plurality of interference modulators, The plurality of interference modulators, One or more interference modulators configured to output red light; One or more interference modulators configured to output green light; One or more interference modulators configured to output blue light; And One or more interference modulators configured to output white light Including; At least one interference modulator configured to output the white light has a normalized white point. The method of claim 7, wherein One or more interference modulator configured to output the red light, one or more interference modulator configured to output the green light, and one or more interference modulator configured to output the blue light are combined to produce white light having a second normalized white point. Display, configured to output. The method of claim 8, And the normalized white point of at least one interference modulator configured to output the white light substantially coincides with the second normalized white point. The method of claim 7, wherein And the normalized white point is one of D55, D65, or D75. The method of claim 7, wherein And a source of illumination for the plurality of interference modulators, the illumination source having a white point different from the generated white light having the normalized white point. The method of claim 7, wherein The at least one interference modulator configured to output the white light includes at least one interference modulator configured to output the cyan light and at least one interference modulator configured to output the yellow light, wherein the cyan light and the yellow light are combined to produce the white light. Generated, display. The method of claim 7, wherein And at least one interference modulator configured to output the white light comprises a broadband reflector. A plurality of display elements each comprising a reflective surface configured to be positioned at a distance from the partially reflective surface, Wherein the plurality of display elements comprises one or more display elements configured to output color light and one or more display elements configured to coherently output white light. The method of claim 14, Wherein said white light is characterized by a normalized white point. The method of claim 15, And the normalized white point is one of D55, D65, or D75. The method of claim 14, And a lighting source for illuminating said plurality of display elements. The method of claim 17, And the illumination source has a different white point than the light reflected by the display. The method of claim 14, Wherein the plurality of display elements comprise one or more display elements configured to output red light, one or more display elements configured to output green light, and one or more display elements configured to output blue light. The method of claim 14, And one or more filters associated with one or more display elements, wherein the filters are configured to selectively transmit certain visible wavelengths and substantially filter other visible wavelengths when the white light is irradiated. The method of claim 14, Wherein at least one of the plurality of display elements configured to output the white light comprises one or more interference modulator configured to output cyan light and one or more interference modulator configured to output yellow light. The method of claim 14, And the plurality of display elements comprise a plurality of interference modulators. The method of claim 14, A processor electrically connected to the plurality of display elements, the processor configured to process image data; And A memory device in electrical connection with the processor Display further including. The method of claim 23, wherein And drive circuitry configured to transmit at least one signal to the plurality of display elements. The method of claim 24, And a controller configured to transmit at least a portion of the image data to the drive circuit. The method of claim 23, wherein And an image source module configured to send the image data to the processor. The method of claim 26, And the image source module comprises one or more of a receiver, transceiver, and transmitter. The method of claim 23, wherein And an input device configured to receive input data and to transmit the input data to the processor. Forming a plurality of display elements each comprising a reflective surface configured to be positioned at a distance from the partially reflective surface Including; Wherein each said distance is selected such that one or more display elements output color light and at least another one of said plurality of display elements coherently output white light. The method of claim 29, Each said distance is selected such that said white light is characterized by a normalized white point. The method of claim 30, Each said distance is selected such that the light reflected by said display has a different white point than the light illuminating said display. The method of claim 30, Wherein each distance is selected such that the white point is one of D55, D65, or D75. The method of claim 29, Forming the at least one of the plurality of display elements configured to output the color light comprises at least one display element configured to output red light, at least one display element configured to output green light, and at least one display configured to output blue light Forming a device. A display produced by the method according to any one of claims 29 to 33. An image display means comprising reflecting means for reflecting light and partially reflecting means for partially reflecting light, The reflecting means is configured to be located away from the partial reflecting means, And said image display means comprises first output means for outputting color light and second output means for coherently outputting white light. 36. The method of claim 35 wherein Said image display means comprising a plurality of display elements, said reflecting means and said partially reflecting means comprising a reflecting surface and a partially reflecting surface, said reflecting surface being configured to be located at a distance from said partially reflecting surface, display. The method of claim 35 or 36, And means for selectively transmitting a predetermined visible wavelength and substantially filtering other visible wavelengths. The method of claim 38, And said selectively transmitting means comprises a filter. The method of any one of claims 35, 36, 37, or 38, Said white light output means comprising means for outputting white light having a normalized white point. The method of claim 39, And the normalized white point is one of D55, D65, or D75. The method of any one of claims 35, 36, 37, 38, 39 or 40, And means for illuminating having a white point different from the white light produced by the first output means and the second output means. The method of claim 41, wherein And said lighting means comprises an illumination source. A plurality of pixels, each comprising a red interference modulator, a green interference modulator, and a blue interference modulator configured to output red light, green light, and blue light, respectively Including; Wherein each said pixel is configured to output green light of intensity stronger than red light and output green light of intensity stronger than blue light when each said interference modulator is set to output red light, green light, blue light. The method of claim 43, Each of the interference modulators of each of the pixels has a reflection area, and the green interference modulator of each pixel has a total reflection area, which is larger than the red interference modulator of each pixel and larger than the blue interference modulator of each pixel, display. The method of claim 43, Wherein each said pixel comprises more interferometric modulators configured to output green light than interferometric modulators configured to output blue light. The method of claim 43, Wherein each said pixel comprises more interferometric modulators configured to output green light than interferometric modulators configured to output red light. The method of claim 43, And the interference modulator configured to output the red light is configured to output red light having a wavelength selected to compensate for the strong intensity of the green light. The method of claim 43, The interferometric modulator configured to output the red light is characterized by an optical path length, wherein the optical path length of the interferometric modulator configured to output the red light is approximately one wavelength, λ, associated with the red light to cause secondary red reflection. Substantially the same, the display. The method of claim 43, And the interferometric modulator configured to output the blue light is configured to output the blue light having a wavelength selected to compensate for the strong intensity of the green light. The method of claim 43, The interferometric modulator configured to output the blue light is characterized by an optical path length, and the optical path length of the interferometric modulator configured to output the blue light is approximately one wavelength, λ, associated with the blue light to effect secondary blue reflection. Substantially the same, the display. The method of claim 43, A processor electrically connected to the plurality of pixels and configured to process image data; And A memory device in electrical connection with the processor Display further including. The method of claim 51, And drive circuitry configured to transmit at least one signal to the display. The method of claim 52, wherein And a controller configured to transmit at least a portion of the image data to the drive circuit. The method of claim 51, And an image source module configured to send the image data to the processor. The method of claim 54, And the image source module comprises one or more of a receiver, transceiver, and transmitter. The method of claim 51, And an input device configured to receive input data and to transmit the input data to the processor. Forming a plurality of pixels Including; Forming the plurality of pixels, Forming an interference modulator configured to output red light; Forming an interference modulator configured to output green light; And Forming an interference modulator configured to output blue light Including; Wherein each said pixel is configured to output green light of intensity stronger than red light and green light of intensity stronger than blue light when each said interference modulator is set to output red light, green light, blue light. The method of claim 57, Each of the interference modulators of each of the pixels has a reflection area, and the green interference modulator of each pixel has a total reflection area, which is larger than the red interference modulator of each pixel and larger than the blue interference modulator of each pixel, Display manufacturing method. The method of claim 57, Wherein each pixel comprises more of an interference modulator configured to output green light than an interference modulator configured to output blue light. The method of claim 57, Wherein each pixel comprises more of an interference modulator configured to output green light than an interference modulator configured to output red light. The method of claim 57, Forming an interference modulator configured to output the red light comprises forming the interference modulator to output red light having a wavelength selected to compensate for the strong intensity of the green light. The method of claim 57, And wherein the interferometric modulator configured to output blue light comprises forming an interferometric modulator to output blue light having a wavelength selected to compensate for the strong intensity of the green light. A plurality of pixels, each comprising a red interference modulator, a green interference modulator, and a blue interference modulator configured to output red light, green light, and blue light, respectively Including; Each said pixel is configured to output green light of intensity stronger than red light and output green light of intensity stronger than blue light, At least one of the interference modulator configured to output the red light and the interference modulator configured to output the blue light is configured to output light having a wavelength selected to compensate for the strong intensity of the green light. The method of claim 63, wherein Further comprising circuitry configured to drive each of the red interference modulator, the green interference modulator, and the blue interference modulator for each time; Wherein the time associated with the green interference modulator is longer than each time associated with the red interference modulator and the blue interference modulator. The method of claim 63, wherein Wherein the wavelength is selected to be substantially equal to λ, about one wavelength associated with red light, such that secondary red reflection is achieved. The method of claim 63, wherein Wherein the wavelength is selected to be substantially equal to about 1 wavelength, λ, associated with the blue light to effect secondary blue reflection. A plurality of red light output means for outputting red light; A plurality of green light output means for outputting green light; And A plurality of blue light output means for outputting blue light Including; The red light output means, the green light output means, and the blue light output means form pixel display means for displaying an image pixel, Each of the pixel display means is configured to output green light of a stronger intensity than blue light when the red light output means, the green light output means, and the blue light output means are set to output red light, green light and blue light, display. The method of claim 67, And the pixel display means comprises a pixel. The method of claim 68, Wherein said red light output means, said green light output means, and said blue light output means comprise a red interference modulator, a green interference modulator, and a blue interference modulator configured to output red light, green light, and blue light, respectively. The method of claim 69, wherein The total reflection area of the green interference modulator of each pixel is larger than the total reflection area of the red interference modulator of each pixel and is larger than the total reflection area of the blue interference modulator of each pixel. A plurality of display elements comprising one or more color display elements configured to output color light; And One or more display elements configured to output white light Including; Wherein the at least one display element configured to output the white light outputs white light having a standardized white point. The method of claim 71, wherein Wherein the at least one display element comprises a red display element, a green display element, and a blue display element configured to output red light, green light, and blue light, respectively. The method of claim 70 or 71, wherein And the plurality of display elements comprise a plurality of interference modulators. Image display means comprising color light output means for outputting color light and white light output means for outputting white light Including; Said white light output means outputting white light having a normalized white point. The method of claim 74, wherein And said image display means comprises a plurality of display elements. 76. The method of claim 75, And the plurality of display elements comprise a plurality of interference modulators. 77. The method of claim 75 or 76, And said color light output means comprises one or more display elements configured to output color light. 78. The method of claim 77 wherein Said white light output means comprising one or more display elements configured to output white light. Forming a plurality of display elements Including; Forming the plurality of display elements, Forming at least one display element configured to output color light and at least one display element configured to output white light, And the one or more display elements configured to output the white light are configured to output white light having a normalized white point. The method of claim 79, Wherein said at least one color display element comprises a red display element, a green display element, and a blue display element configured to output red light, green light, and blue light, respectively. The method of claim 79, And the plurality of display elements comprise a plurality of interference modulators. The display produced by the method of any one of Claims 57-62. A display produced by the method of any one of claims 79-81.

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