KR20100094511A - Thin film planar sonar concentrator/ collector and diffusor used with an active display - Google Patents

Abstract

In various embodiments described herein, the display device 85 includes photoconductive devices 80, 84 and photovoltaic elements 86, 100, disposed on edges 88 of the condensing films 80, 84. 200). The light collecting films 80 and 84 may include a plurality of light-turning elements for redirecting light between the front or rear surfaces of the light collecting films 80 and 84 and the photovoltaic elements 86, 100 and 200. 94, 108). In some embodiments, light sources 90 and 174 are also disposed on the edges 88 of the light collecting films 80 and 84 to emit light, which light is redirected to the light-turning features 94, 108 is turned toward the display device.

Description

THIN FILM PLANAR SONAR CONCENTRATOR / COLLECTOR AND DIFFUSOR USED WITH AN ACTIVE DISPLAY}

Cross Reference to Related Applications

This application claims the benefit of US Provisional Application No. 61 / 093,686 (filed September 2, 2008) and US Patent Application No. 11 / 941,851 (filed November 16, 2007). Patent application 12 / 207,270 filed September 9, 2008.

Technical field of invention

The present invention relates to microelectromechanical systems (MEMS).

Microelectromechanical systems (MEMS) include micromechanical elements, actuators and electronic devices. A micromechanical element may be a substrate and / or deposition that deposits a portion of a deposited (or deposited; hereafter referred to as "deposition") or adds layers to form an electromechanical device, It may be formed using etching and / or other micromachining processes. One type of MEMS device (or device) is called an interferometric modulator ("IMOD"). As used herein, the term interferometric modulator, interferometric light modulator or IMOD refers to a device that selectively absorbs and / or reflects light using the principles of optical interference. In certain embodiments, the interferometric modulator may comprise a pair of conductive plates, wherein either or both of the pair of conductive plates may be transmissive and / or reflective in whole or in part and may be suitable for If you do, you can do relative exercises. In certain embodiments, one conductive plate may include a pinned layer deposited on a substrate, and the other conductive plate may include a metal film separated from the fixed layer by an air gap. As will be explained in more detail herein, the optical interference of light incident on the interferometric modulator can be varied by the relative position of the conductive plate.

The IMOD can be arranged in an addressable array to create an active display (ie, display). Similarly, other MEMS and non-MEMS technologies such as liquid crystal displays (LCDs), organic LEDs (OLEDs), light emitting diodes (LEDs), electrophoretic and field emission displays (FEDs), etc. are all televisions, computer monitors, cell phones or PDAs. (personal digital assistant) It is used as an active display for a screen or the like. Such devices have a wide range of uses and / or utilize the features of these devices so that these types of device characteristics can be used to improve existing products and to create new products that have not yet been developed. Modifications would be advantageous in the art.

In one embodiment, the display device comprises: an active array of display pixels having a front display surface facing the viewer and a back display surface; A front condensing film surface, a rear condensing film surface, at least one edge and a plurality of light-turning features (or light-turning features), respectively, the front display At least one collection film adjacent to either the face or back display; And a photovoltaic device (or photovoltaic device) disposed on an edge of the light collecting film and oriented to receive light transmitted transversely through the light collecting film surface from the light-turning features. Wherein the light-turning features are configured to redirect light between the front or rear light collecting film surface and an edge of the light collecting film.

In another embodiment, the display device includes an array of display pixels. At least one light collecting film is disposed after the array of display pixels. The light collecting film has a plurality of light-turning features, the light-turning features being configured to redirect light between the front or back light-collecting film surface and the edges of the light-collecting film. At least one photovoltaic element is disposed at the first edge of the condensing film, the photovoltaic element being oriented to receive light transmitted transversely through the condensing film surface from the light-turning features. . At least one light source is disposed at the edge portion, and the light source emits light laterally through the light collecting film to be redirected by the light-turning features toward the array of display pixels.

In another embodiment, a display device comprises: means for displaying an image on an array of display pixels; Means for converting light energy into other forms of energy; And means for redirecting light in the transverse direction along the display surface from the direction incident on the display surface toward the means for converting the light energy into another form of energy.

In another embodiment, a method of focusing light and displaying an image comprises the steps of: actively displaying an image in an image area; Focusing light from the image area; Redirecting light from the image area to at least one edge of the image area; And converting light into a current.

In another embodiment, a method of manufacturing a display device includes operatively coupling a light collecting film to a front or rear display surface of an active array of display pixels. The light collecting film has a front light collecting film face, a back light collecting film face, at least one edge portion and a plurality of light-turning features. The method also directs the photovoltaic device to the light collecting film such that ambient light is directed by the light-turning features from the front light collecting film surface to the photovoltaic device at the edge of the light collecting film and converted into electrical energy. And aligning with an edge of the.

1 is an isometric view of a portion of an embodiment of an interferometric modulator display with a movable reflective layer of a first interferometric modulator in a relaxed position and a movable reflective layer of a second interferometric modulator in an operating position;
2 is a system block diagram illustrating one embodiment of an electronic device incorporating a 3x3 interferometric modulator display.
3 is a diagram showing the position of the movable mirror versus the applied voltage for one exemplary embodiment of the interferometric modulator of FIG. 1;
4 shows a set of row and column voltages that can be used to drive an interferometric modulator display;
5A illustrates one exemplary frame of display data in the 3x3 interferometric modulator display of FIG.
FIG. 5B illustrates one exemplary timing diagram of the row and column signals that may be used to write the frame of FIG. 5A; FIG.
6A and 6B are system block diagrams illustrating one embodiment of a visual display device including a plurality of interferometric modulators.
7A is a cross-sectional view of the device of FIG. 1;
7B is a cross-sectional view of an alternative embodiment of an interferometric modulator;
7C is a cross-sectional view of another alternative embodiment of an interferometric modulator;
7D is a cross-sectional view of another alternative embodiment of an interferometric modulator;
7E is a sectional view of a further alternative embodiment of an interferometric modulator;
8 schematically shows a cross section of one condensing film and associated photovoltaic element overlying an array of display pixels and another such condensing film underlying said array of display pixels;
9 shows schematically a cross section of a light collecting film overlying an array of display pixels, an associated photovoltaic element and a light source, and another such light collecting film underlying said array of display pixels;
10A is a plan view of a light collecting film with light-turning features, wherein the photovoltaic element and light source are disposed next to each other at one corner of the light collecting film;
10B schematically illustrates an edge portion of one embodiment of a light collecting film having a photovoltaic element and a light source;
10C is a schematic diagram illustrating a further embodiment of the arrangement of the photovoltaic element and the light source;
FIG. 11A is a schematic side cross-sectional view of a prism condensing film including a plurality of prismatic features for condensing and guiding light onto a photovoltaic device; FIG.
FIG. 11B is another schematic cross-sectional view of a prism condensing film including a plurality of prismatic features for condensing and guiding light onto a photovoltaic device; FIG.
FIG. 11C is another schematic cross-sectional view of a prism condensing film including a plurality of prism slits that condense and guide light to a photovoltaic device; FIG.
FIG. 11D illustrates an embodiment comprising two layers of prismatic light condensing films stacked with staggered components that condense and guide light at greater efficiency into a photovoltaic device; FIG.
12 is a schematic view of a light collecting film including diffractive redirecting features;
FIG. 13A is a schematic illustration of a light-turning arrangement comprising a transmissive hologram disposed on an upper surface of the light collecting film; FIG.
FIG. 13B is a schematic illustration of a light-turning feature including a reflective hologram disposed on the bottom surface of the light collecting film; FIG.
14 is a schematic cross-sectional view of one embodiment of a reflective interferometric modulator display with a light collecting film on the front side;
15 is a schematic cross-sectional view of one embodiment of a reflective interferometric modulator display with a light collecting film on the back side;
16 is a schematic plan view of an array of active (or active) display pixels arranged in a row and column direction;
17A is a schematic cross-sectional view of a transflective interferometric modulator (IMOD) display with backlight;
FIG. 17B is a schematic cross sectional view of a transflective IMOD display provided with a backlight by a condensing / lighting film with a redirecting feature; FIG.
18 is a schematic cross-sectional view of one embodiment of an emissive display with a light collecting film on the front side;
19 is a schematic cross-sectional view of an embodiment of a light emitting display device having a light collecting film on a rear side thereof;
20 is a schematic cross-sectional view of another embodiment of a light emitting display device having a light collecting film between active display pixels and a backlight;
21 is a schematic cross-sectional view of another embodiment of a light emitting display device having a light collecting film with asymmetrical redirecting features.

Although the following detailed description relates to any particular embodiment of the present invention, the present invention may be implemented in various ways. In this description, the same parts will be described with reference to the drawings denoted by the same reference numerals. As will be apparent from the description below, each embodiment displays an image according to whether it is a moving image (e.g. video) or a still image (e.g. still image), and whether it is a character or a picture. Any device may be implemented as long as the device is configured to do so. More specifically, mobile phones, wireless devices, personal data assistants (PDAs), micro or portable computers, GPS receivers / navigations, cameras, MP3 players, camcorders, game consoles, wrist watches, watches, calculators, television monitors Flat panel displays, computer monitors, automotive displays (e.g., odometer displays, etc.), cockpit controls and / or displays, camera view displays (e.g., rear view cameras of vehicles) Display), electronic photographs, electronic billboards or signs, projectors, architectural structures, packages and art structures (e.g., display of images for jewelry), or implemented in various electronic devices, including but not limited to It is contemplated that this may be associated with various electronic devices.

Certain embodiments of the present invention relate to a condensing film coupled with a photovoltaic device that collects light through an active display region and converts the light into electrical energy. The light collecting film disposed above or below the array of display pixels shunts light to an edge of the light collecting film in which at least one photovoltaic element is located by reorienting a part of the light received on the active display area. That is, light-turning features that rotate in different directions. In some embodiments, a light source, such as an LED, is also disposed at the edge of the same film to emit light, which light is redirected by the light-turning feature to illuminate the display.

While the embodiments of FIGS. 8-20 may utilize a light collecting film with photovoltaic elements in connection with various display technologies, FIGS. 1-7E illustrate an interferometric modulator (IMOD) display available for the embodiments of FIGS. 8-20. The technique is illustrated.

One embodiment of an interferometric modulator display including an interferometer MEMS display element is illustrated in FIG. 1. In these devices, the pixels are in a bright state or a dark state. In the bright ("on" or "open") state, the display element reflects a large portion of the incident visible light to the user. When in the dark (“off” or “closed”) state, the display element reflects little incident visible light to the user. Light reflection characteristics of the "on" and "off" states may be reversed depending on the embodiment. MEMS pixels are configured to reflect preferentially in the selected color to enable color display in addition to black and white.

1 is an isometric view showing two adjacent pixels in a series of pixels of a visual display, where each pixel comprises a MEMS interferometric modulator. In certain embodiments, the interferometric modulator display comprises a row / column array of these interferometric modulators. Each interferometric modulator includes a pair of reflective layers located at variable and controllable distances from each other to form a resonant optical gap with at least one variable dimension. In one embodiment, one of the reflective layers may move between two positions. In a first position, also referred to herein as a relaxed position, the movable reflective layer is located relatively far from the fixed partial reflective layer. In a second position, also referred to herein as an operating position, the movable reflective layer is located closer to the partial reflective layer. Incident light reflected from these two layers constructively or destructively interferes depending on the position of the movable reflective layer to produce an overall reflective state or non-reflective state for each pixel.

The illustrated portion of the pixel array in FIG. 1 includes two adjacent interferometric modulators 12a and 12b. In the interferometric modulator 12a located on the left side, the movable reflective layer 14a is illustrated at a relaxed position away from the optical stack 16a including the partial reflective layer. The interferometric modulator 12b located on the right side illustrates the movable reflective layer 14b in an operating position adjacent to the optical stack 16b.

Optical stacks 16a, 16b (collectively referred to as optical stacks 16), as indicated herein by reference symbols, typically comprise several fused layers, these fused layers Electrode layers such as silver indium tin oxide (ITO), partially reflective layers such as chromium, and transparent dielectrics. Thus, the optical stack 16 is electrically conductive, partially transparent, partially reflective, and can be manufactured, for example, by depositing one or more of the above layers onto the transparent substrate 20. The partially reflective layer (ie, partially reflective layer) can be formed from various partially reflective materials such as various metals, semiconductors, dielectrics, and the like. This partially reflective layer may be formed of one or more layers of material, and each layer may be formed of a single material or a combination of materials.

In some embodiments, as will be described further below, the layers of the optical stack 16 may be patterned into parallel strips and form row electrodes in the display. The movable reflective layers 14a and 14b are the intervening sacrificial material deposited between the pillar (or support) 18 and the deposition metal layer or deposition metal layers deposited on the top surface of the pillar 18 (optical stack 16a). ), Orthogonal to the row electrodes of 16b). When the sacrificial material is etched and removed, the movable reflective layers 14a and 14b are separated from the optical stacks 16b and 16b by a predetermined gap 19. Highly conductive and reflective materials such as aluminum may be used for the reflective layers 14a and 14b, and these strips may form columnar electrodes in the display.

As illustrated by the pixel 12a in FIG. 1, when no voltage is applied, the gap 19 is the movable reflective layer 14a and the optical stack 16a in a state where the movable reflective layer 14a is mechanically relaxed. Is maintained between). However, when a potential difference is applied to the selected rows and columns, the capacitor formed at the intersection of the row and column electrodes in the corresponding pixel is charged and the electrostatic force pulls the electrodes together. If the voltage is high enough, the movable reflective layer 14 deforms and exerts a force on the optical stack 16. As indicated by the pixel 12b located on the right side of FIG. 1, the dielectric layer (not shown in FIG. 1) in the optical stack 16 is prevented from shorting to adjust the separation distance between the layers 14 and 16. do. This behavior is the same regardless of the polarity of the applied potential difference. In this way, the row / column operation that can control the reflective pixel state versus the non-reflective pixel state is similar in many ways to those used in conventional LCD and other display technology.

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

2 is a system block diagram illustrating one embodiment of an electronic device that may incorporate aspects of the present disclosure. In an exemplary embodiment, the electronic device includes a processor 21, which includes ARM, Pentium®, Pentium II®, Pentium III®, and Pentium IV ( General purpose single-chip microprocessor or multi-chip microprocessors such as PRT®, Pentium® Pro, 8051, MIPS®, Power PC®, ALPHA®, or digital signal processor, micro It may be some special purpose microprocessor, such as a controller, or a programmable gate array. As is conventional in the art, the processor 21 may be configured to execute one or more software modules. In addition to the execution of an operating system, the processor may be configured to execute one or more software applications, including a web browser, a telephone application, an email program, or any other software application.

In one embodiment, the processor 21 is also configured to communicate with the array driver 22. In one embodiment, the array driver 22 includes a row driver circuit 24 and a column driver circuit 26 that provide signals to the display array or panel 30. The cross section of the array illustrated in FIG. 1 is indicated by line 1-1 of FIG. 2. For MEMS interferometric modulators, the row / column operation protocol may utilize the hysteresis characteristics of these devices shown in FIG. For example, a potential difference of 10 volts may be needed to deform the movable layer from the relaxed state to the operating state. However, if the voltage decreases from this value, the movable layer remains in that state when the voltage drops back below 10 volts. In the exemplary embodiment of FIG. 3, the movable layer does not fully relax until the voltage drops below 2 volts. Thus, in the example illustrated in FIG. 3, there is a window of applied voltage of about 3 to 7 V, within which the device is stable in a relaxed or operating state. This is referred to herein as a "hysteresis window" or "stability window". For the display array with the hysteresis characteristic of FIG. 3, the pixels to be operated in the strobe row during row strobing are exposed to a voltage difference of about 10 volts, and the pixels to be relaxed are close to zero volts. Row / column operating protocols can be designed to be exposed to After strobing, the pixels are exposed to a steady state voltage difference of about 5 volts, so they remain in the state where the row strobe left the pixels. In this example, each pixel, after being written, exhibits a potential difference within a "stable window" of 3 to 7 volts. This characteristic stabilizes the pixel design illustrated in FIG. 1 under the same applied voltage conditions in the existing state of operation or relaxation. Since each pixel of the interferometric modulator is essentially a capacitor formed by the fixed reflective layer and the movable reflective layer depending on whether it is operating or relaxed, this stable state can be maintained at the voltage in the hysteresis window with little power loss. If the applied potential is fixed, there is substantially no current flow into the pixel.

In a typical application, the display frame may be created by asserting a set of column electrodes in accordance with the desired set of working pixels in the first row. Next, a row pulse is applied to the electrodes of the first row to operate the pixels corresponding to the asserted column direction lines. Thereafter, the asserted set of columnar electrodes is changed to correspond to the desired set of working pixels in the second row. A pulse is then applied to the electrodes in the second row, actuating the appropriate pixels in the second row according to the asserted column electrodes. The pixels in the first row remain unaffected by the pulses in the second row and remain as they were set during the pulses in the first row. This may be repeated sequentially for a whole series of rows to create a frame. In general, by repeating this process by the desired number of frames per second, the frames are refreshed and / or updated with new display data. In addition, a wide variety of protocols for driving the row and column electrodes of the pixel array for creating the display frame are well known, which may be used in connection with the present invention.

4, 5A and 5B illustrate one possible operating protocol for generating display frames on the 3x3 array of FIG. FIG. 4 illustrates a possible set of row voltage levels and column voltage levels that may be used for the pixel representing the hysteresis curve of FIG. 3. In the embodiment of Figure 4, to operate the pixel it is necessary to set the appropriate column to -V _bias and the appropriate row to + ΔV, where -V _bias And + ΔV correspond to −5 volts and +5 volts, respectively. Pixel relaxation is accomplished by setting the appropriate rows with the same + ΔV, where the volt potential difference for the pixels is zero, and setting the appropriate columns with + V _bias . In these rows where the row voltage remains at zero volts, the pixels are stable whatever their original state, regardless of whether the column is a -V _bias or a + V _bias . As also illustrated in FIG. 4, it will be appreciated that voltages of opposite polarity to those described above may be used. For example, turning on a pixel sets the appropriate column to + V _bias This may involve setting the appropriate row to -ΔV. In this embodiment, pixel relaxation is performed by setting the appropriate row with the same -ΔV and the appropriate column with -V _bias , which produce a zero volt potential difference for the pixel.

FIG. 5B is a timing diagram illustrating a series of row and column signals applied to the 3x3 array of FIG. 2 in the display configuration illustrated in FIG. 5A, wherein the operational pixels are non-reflective. Prior to writing the frame illustrated in FIG. 5A, the pixels may be in any state, in this example, all rows are zero volts and all columns are +5 volts. According to these applied voltages, the pixels are all stable in their existing operating or relaxed state.

In the frame of Fig. 5A, (1,1), (1,2), (2,2), (3,2) and (3,3) pixels are operated. To accomplish this, the first and second columns are set to -5 volts and the third column is set to +5 volts during the "line time" for the first row. This does not change the state of any pixels because all the pixels remain in the 3 to 7 volt stability window. Next, the first row is strobe with pulses going from zero to five volts and back to zero volts. This operates the (1,1) pixel and the (1,2) pixel and relaxes the (1,3) pixel. Other pixels in the array are not affected. To set the second row as desired, set the second column to -5 volts and the first and third columns to +5 volts. Next, the same strobe applied to the second row will activate the (2,2) pixels and relax the (2,1) and (2,3) pixels. Again, other pixels of the array are not affected. The third row is similarly set by setting the second column and the third column to -5 volts and the first column to +5 volts. The strobe of the third row sets the pixels of the third row as shown in FIG. 5A. After writing the frame, the row potentials can be zero and the column potentials can be held at +5 volts or -5 volts, so that the display is stable in the configuration of FIG. 5A. It will be appreciated that the same process can be used for arrays with tens or hundreds of rows and columns. In addition, the timing, procedure, and voltage levels used to perform the row and column operations can vary widely within the general principles of the foregoing, the examples are merely illustrative, and other operating voltage methods are described herein. It will also be appreciated that it can be used with systems and methods.

6A and 6B are system block diagrams illustrating one embodiment of the display device 40. For example, the display device 40 may be a mobile phone or a mobile phone. However, the same components of the display device 40 or some variations thereof may also include various types of displays, such as televisions, portable media players, and computers.

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. In general, the housing 41 is formed by any of a variety of manufacturing processes well known to those skilled in the art, including injection molding and 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 a combination thereof. In one embodiment, the housing 41 includes detachable portions (not shown) that may be compatible with the detachable portions having different colors or including different logos, pictures or symbols.

The display 30 of the exemplary display device 40 may be any of a variety of displays, including bistable displays, as described herein. In another embodiment, the display 30 may be a flat panel display, such as a plasma, EL, OLED, STN LCD or TFT LCD, as described above, or non-flat, such as a CRT or other type of tube device. flat-panel) display. However, for the purpose of describing this embodiment, the display 30 includes an interferometric modulator display as described herein.

Components of one embodiment of exemplary display device 40 are schematically illustrated in FIG. 6B. The exemplary display device 40 shown may include a housing 41 and may include additional components at least partially housed therein. For example, in one embodiment, exemplary display device 40 includes a network interface 27 that includes an antenna 43 coupled to a transceiver 47. The transceiver 47 is connected to the processor 21, which is connected to conditioning hardware 52. Conditioning hardware 52 may be configured to adjust the signal (eg, filter the signal). Conditioning hardware 52 is connected to a speaker 45 and a microphone 46. The processor 21 is also connected to the input device 48 and the driver controller 29. The driver controller 29 is coupled to the frame buffer 28 and to the array driver 22, which is then coupled to the display array 30. Power supply 50 provides power to all components as required for a particular exemplary display 40 design.

The network interface 27 includes an antenna 43 and a transceiver 47 so that the exemplary display device 40 can communicate with one or more devices over a network. In one embodiment, network interface 27 may also have some processing power that can mitigate the requirements of processor 21. Antenna 43 is any antenna known to those skilled in the art for transmitting and receiving signals. In one embodiment, the antenna transmits and receives RF signals in accordance with IEEE 802.11 standards, including IEEE 802.11 (a), (b), or (g). In another embodiment, the antenna transmits and receives RF signals in accordance with the BLUETOOTH standard. In the case of a mobile phone, the antenna is designed to receive CDMA, GSM, AMPS or other known signals used for communication within a wireless mobile telephone network. The transceiver 47 may process the signal received from the antenna 43 in advance so that the signal may be received by the processor 21 and further manipulated. The transceiver 47 also processes the signal received from the processor 21 so that the signal can be transmitted from the exemplary display device 40 via the antenna 43.

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

The processor 21 generally controls the overall operation of the exemplary display device 40. The processor 21 receives data such as compressed image data from the network interface 27 or the image source, and in a format capable of immediately processing the data as raw image data or as source image data. Process. Processor 21 then sends the processed data to driver controller 29 or to frame buffer 28 for storage. Source data typically refers to information that identifies image characteristics at each location within an image. For example, such image characteristics may include color, saturation or saturation and gray-scale level.

In one embodiment, the processor 21 includes a microcontroller, CPU, or logic unit that controls the operation of the exemplary display device 40. Conditioning hardware 52 generally includes amplifiers and filters to send a signal to speaker 45 and to receive a signal from microphone 46. The conditioning hardware 52 may be a separate component within the exemplary display device 40 or may be embedded within the processor 21 or other components.

The driver controller 29 appropriately reformats the original image data for high speed transfer to the array driver 22 by taking the original image data generated by the processor 21 directly from the processor 21 or from the frame buffer 28. . In particular, the driver controller 29 has a time sequence suitable for reformatting the source image data into a data flow with a raster like format to scan across the display array 30. The driver controller 29 then sends the formatted information to the array driver 22. Although driver controller 29, such as an LCD controller, is often associated with system processor 21 as a stand-alone integrated circuit (IC), such controllers may be implemented in various ways. They may be inserted as hardware into the processor 21, may be inserted into the processor 21 as software, or may be fully integrated into the hardware with the array driver 22.

Typically, array driver 22 receives formatted information from driver controller 29 and outputs video data in parallel sets of waveforms that are applied multiple times per second to hundreds, sometimes thousands, of lead lines from the xy matrix pixels of the display. Reformat the.

In one embodiment, driver controller 29, array driver 22, and display array 30 are suitable for any of the types of displays described herein. For example, in one embodiment, the driver controller 29 is a conventional display controller or bistable display controller (eg, 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. One such embodiment is common in highly integrated systems such as mobile phones, watches and other small displays. In yet another embodiment, display array 30 is a typical display array or bistable display array (eg, a display comprising an array of interferometric modulators).

The input device 48 allows a user to control the operation of the exemplary display device 40. In one embodiment, the input device 48 includes a keypad, a button, a switch, a touch sense screen, a pressure sensitive film or a thermal film, such as a QWERTY keyboard or a telephone keypad. In one embodiment, the microphone 46 is an input device for the exemplary display device 40. When the microphone 46 is used to input data to the device, voice commands may be provided by the user to control the operations of the exemplary display device 40.

Power supply 50 may include various energy storage devices that are well known in the art. For example, in one embodiment, the power supply 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, a capacitor, or a solar cell, including a plastic solar cell, solar cell paint. In another embodiment, the power supply 50 is configured to receive power from a wall outlet.

In some embodiments, the control program resides in a driver controller that can be located at several places in the electronic display system as described above. In certain embodiments, the control program resides in the array driver 22. Those skilled in the art will appreciate that the optimization conditions described above may be implemented in a number of hardware and / or software components and in various forms.

The detailed structure of the interferometric modulator operated in accordance with the principles described above can vary widely. For example, FIGS. 7A-7E (hereinafter sometimes referred to collectively as "FIG. 7") represent five different embodiments of the movable reflective layer 14 and its supporting structure. 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 support 18 extending in an orthogonal direction. In FIG. 7B, the movable reflective layer 14 is attached to the support at the corner only on the tether 32. In FIG. 7C, the movable reflective layer 14 is suspended from a deformable layer 34, which may comprise a flexible metal. This deformable layer 34 is connected directly or indirectly to the substrate 20 around the deformable layer 34. These connections (or connections) are also referred to herein as supports 18, which can take the form of pillars, struts, rails or walls. The embodiment shown in FIG. 7D has a support pillar plug 42 on which the deformable layer 34 rests. The movable reflective layer 14 remains suspended over the gap as in FIGS. 7A-7C, but the deformable layer 34 fills the holes between the deformable layer 34 and the optical stack 16. Does not form a support column Rather, the support 18 is formed of a flattening material, which is used to form the support pillar plug 42. The embodiment shown in FIG. 7E is based on the embodiment shown in FIG. 7D, but may be adapted to work with 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 the signal to be transmitted along the backside of the interferometric modulator, eliminating a number of electrodes that may otherwise be formed on the substrate 20.

In embodiments such as those shown in FIGS. 7A-7E, the interferometric modulator functions as a direct-view device, wherein the images are seen from the front side of the transparent substrate 20 and the modulators are arranged opposite. have. In these embodiments, the reflective layer 14 optically blocks a portion of the interferometric modulator on the side of the reflective layer opposite the substrate 20, including the deformable layer 34. This allows the blocked area to be constructed and operated without adversely affecting the image quality. This blocking allows the bus structure 44 in FIG. 7E, which provides the ability to separate the optical properties of the modulator from the electromechanical properties of the modulator, such as addressing and movement resulting from the addressing. This separable modulator structure selects the materials and structural designs used for the optical and electromechanical aspects of the modulator to function independently of each other. Moreover, the embodiment shown in FIGS. 7C-7E has additional advantages obtained by separating the optical properties of the reflective layer 14 from the mechanical properties performed by the deformable layer 34. This optimizes the structural design and materials used for the reflective layer 14 for optical properties and the structural designs and materials used for the deformable layer 34 for the desired mechanical properties.

In some embodiments as shown in FIGS. 8 and 9, the front (or front side) light collecting film 80 is disposed on or on the front side of the array of display pixels 82. The rear (or rear side) light collecting film 84 is disposed below or on the rear side of the array 82 of display pixels. The array of display pixels 82 may be reflective and may also be an LCD, MEMS device (e.g., interferometric modulator or IMOD display), electrophoretic device, or other type of display technology that reflects light from the front or viewing side (display). Technology). The array of display pixels 82 may be emissive, and may also be a liquid crystal display (LCD), a light emitting diode (LED), an organic light emitting diode (OLED), a field emission display (FED), a backlit (ie, backlit) ) Microelectromechanical system (MEMS) devices (eg, transflective and backlit interferometric modulator displays (IMOD)), or other types of display technologies that generate and emit light internally. As used herein, “light emitting” display technology includes backlit technology.

In certain embodiments, the display device 85 may be formed of only the front light collecting film 80. In another embodiment, the display device 85 may be formed of only the rear light collecting film 84. FIG. 8 shows one embodiment in which the front and rear condensing films 80, 84 have photovoltaic (PV) elements 86 disposed on the edges 88 of the condensing films 80, 84, respectively. Doing. FIG. 8 is a schematic diagram, schematically showing the relative positions of condensing films, PV elements and active displays such that a portion of the light received by the display or image area is shunted to the PV element.

FIG. 9 shows another embodiment in which both the photovoltaic element 86 and the light source 90 are disposed on the edge portion 88 of the light collecting films 80 and 84. In some embodiments, photovoltaic element 86 and light source 90 may be disposed adjacent to each other. In another embodiment, the photovoltaic (PV) device 86 and the light source 90 are disposed at different locations on the edges 88 of the light collecting films 80, 84. According to FIG. 8, the device may comprise either or both of the front side light collecting film 80 and the rear side light collecting film 84, or as shown. As in FIG. 8, part of the light from or to the image region of the active display is split into PV elements on the edge of the image region; In addition, the light collecting film redirects a portion of the light from the light source at the edge toward the image area of the display array 82. However, the PV element 86 and the light source 90 need not be on the same edge portion of the light collecting films 80 and 84 or on the same side of the edge portion 88.

In the embodiment shown in FIG. 9, the light collecting films 80, 84 may have a structure similar to that of FIG. 8. However, these light collecting films 80 and 84 can also serve as illumination films when the light from the light source 90 travels in a direction opposite to the light reaching the photovoltaic element 86. Condensing films 80 and 84 include light-turning features as can be better understood from FIGS. 11A-13B described below. The light source may include, for example, a light emitting diode (LED).

The light collecting films 80 and 84 each comprise two sides. The upper surface is configured to receive ambient light, and the lower surface is disposed below the upper surface. The light collecting films 80 and 84 are completely surrounded by the edges 88. Typically, the length and width of the light collecting films 80 and 84 are substantially larger than the thickness of the light collecting films 80 and 84. The thickness of the light collecting films 80 and 84 can be varied, for example, from 0.5 to 10 mm. The area of the main faces of the light collecting films 80 and 84 can be varied from 0.01 to 10,000 cm 2. In some embodiments, the refractive index of the material comprising the light collecting films 80 and 84 is higher than the peripheral medium to guide large portions of ambient light in the light collecting films 80 and 84 by total internal reflection (TIR). Can be quite high.

10A-10C illustrate various configurations for disposing both the photovoltaic element 86 and the light source 90 on the edges 88 of the light collecting films 80, 84. In some embodiments, the light source 90 can be omitted. In the embodiment shown in FIG. 10A, the photovoltaic element 86 and the light source 90 are arranged side by side at the corners 92 of the light collecting films 80, 84. Condensing film 80, 84 includes light-turning features 94 schematically indicated by an arc on the surface of condensing film 80, 84. The light-turning features are laterally directed toward the edge 88 of the light collecting films 80 and 84 from the direction of incidence of the prism, diffusion, hologram mechanism, or top or bottom surface of the light collecting films 80 and 84. It may be any other mechanism for diverting light. In some embodiments, the photovoltaic device 86 and / or light source 90 may be disposed centrally along one side of the edge 88 rather than at the edge 92 of the light collecting films 80, 84. . Although FIG. 10A illustrates a photovoltaic element 86 and a light source 90 disposed adjacent to each other, the photovoltaic element 86 and the light source 90 are also concentric in shape, as shown in FIGS. 10B and 10C. Or may overlap, or may be arranged at different locations on the edges 88 of the light collecting films 80, 84, eg, cross each other. In some embodiments, the light collecting films 80, 84 are provided with a plurality of photovoltaic elements 86 and / or light sources 90 disposed at various locations on the edges 88 of the light collecting films 80, 84. It is provided.

11A-13B show examples of a condensing film with light-turning features that can be used for condensing and photovoltaic conversion of light, or condensing and illuminating the display 85.

One embodiment of a prism condensing film used to operatively couple ambient light into a photovoltaic device is shown in FIG. 11A. The prism light guide collector is based on the principle of reciprocity, that is, the light can travel back and forth along the path between the surface and the edge of the prism light collecting film. 11A shows a side view of one embodiment that includes a light collecting film 104 disposed relative to the photovoltaic device 100. In some embodiments, the light collecting film 104 includes a substrate 105 and a plurality of prismatic features 108 formed thereon or therein. The light collecting film 104 may include an upper surface 103 and a lower surface 140 with a plurality of edges 110 therebetween. Light 112 incident on the light collecting film 104 is directed into the light collecting film 104 by a plurality of prismatic features 108 and is collected by the plurality of total internal reflections at the top and bottom surfaces. Can be guided transversely within. Condensing film 104 may comprise an optically transmissive material that is transparent to radiation at one or more wavelengths at which the photovoltaic device is sensitive. For example, in one embodiment, the light collecting film 104 may be transparent to wavelengths in the visible and near infrared regions. In other embodiments, the light collecting film 104 may be transparent to the wavelength of the ultraviolet or infrared region. The light collecting film 104 may be formed of a rigid or semi-rigid material, such as glass or acrylic, to provide structural stability for this embodiment. Alternatively, the light collecting film 104 may be formed of a flexible material, such as a flexible polymer.

In one embodiment, as shown in FIG. 11A, the light-turning features in the form of prismatic features 108 are positioned on the bottom surface 104 of the substrate 105 or away from the light source. . Prism features 108 are generally elongated grooves formed on bottom surface 140 of substrate 105. These grooves may be filled with an optically transmissive material. Prism features 108 may be formed on the bottom surface of substrate 105 by molding, embossing, etching, or other alternative techniques. Alternatively, prismatic features 108 may be disposed on a film that may be stacked on the bottom surface of substrate 105. In some embodiments including a prism film, light can be guided solely into the prism film. In such embodiments, the substrate 105 may provide only structural stability. Prism features 108 may include various shapes. For example, prismatic features 108 may be linear v-grooves or slits. Alternatively, prismatic features 108 may comprise curved grooves or non-linear shapes.

11B shows an enlarged view of the prismatic features in the form of a linear v-groove 116. The v-shaped groove 116 comprises two planar facets F1, F2 arranged at an angle α between them as shown in FIG. 11B. The angular spacing α between the facets may depend on the refractive index of the light collecting film 104 or the surrounding medium, which may vary from 15 ° to 120 °. In some embodiments, the facets F1, F2 may be the same length. In the illustrated asymmetrical embodiment, the length of one of the facets is greater than the other. The distance between two consecutive v-shaped grooves 'a' can vary from 0.01 to 0.5 mm. The width of the v-shaped groove marked 'b' may vary from 0.001 to 0.100 mm, while the depth of the v-shaped groove marked 'd' may vary from 0.001 to 0.5 mm.

11C shows an enlarged view of the prismatic features in the form of asymmetric slits 108. These slits 108 comprise two substantially parallel planar facets F3 and F4 arranged at an angle β with the condensing film surface. The angle β between the light collecting film face and the slits may depend on the refractive index of the light collecting film 104 or the surrounding medium, which may vary from 5 ° to 70 °. The planar facet F3 receives light from the front condensing film surface 130 by a plurality of internal reflections at the front and rear condensing film surfaces 130 and 140 at one edge portion of the condensing film 104. Change direction laterally. The planar facet F4 receives light (from the rear light collecting film face 140 to the opposite edge 110 of the light collecting film 104 by a number of internal reflections on the front and rear light collecting film faces 130, 140). Direction 112).

11A and 11C, the photovoltaic device 100 is disposed laterally with respect to the light collecting film 104 adjacent to the edge portion 110 of the film 104. The photovoltaic device 100 is configured and oriented to receive redirected light through the light collecting film 104 by the prismatic features 108. The photovoltaic device 100 may comprise a single layer or multiple layer p-n junction and may also be made of other semiconductor materials such as silicon, amorphous silicon or cadmium telluride. In some embodiments, photovoltaic device 100 may be based on optochemical cells, polymers or nanotechnology. The photovoltaic device 100 may also include thin multispectral layers. These multispectral layers may further comprise nanocrystals dispersed in the polymer. Several multispectral layers can be stacked to increase the efficiency of the photovoltaic device 100. 11A and 11B illustrate one embodiment in which the photovoltaic device 100 is disposed along one edge 110 of the light collecting film 104 (eg, to the left of the light collecting film 104). It is shown. However, other photovoltaic elements may also be disposed at other edges of the light collecting film 104 (eg, to the right of the light collecting film 104). Multiple photovoltaic devices can be disposed at opposite edges of the light collecting film 104 (eg, to the left and right of the light collecting film 104), as shown in FIG. 11C. Other arrangements for positioning the photovoltaic device 100 relative to the light collecting film 014 are possible.

Light incident on the top surface of the light collecting film 104 is transmitted through the light collecting film 104 as indicated by the light path 112. When the light impinges on the facet of the prismatic features 108, it is totally reflected internally by a number of reflections from the upper and lower surfaces 130, 140 of the light collecting film 104. The light rays collide with the edge 110 of the light collecting film 104 and then exit the light collecting film 104 and are optically coupled to the photovoltaic device 100. Lenses or light pipes may be used to optically couple the light from the light collecting film 104 to the photovoltaic device 100. In one embodiment, for example, the light collecting film 104 may be free of prismatic features 108 toward an end closer to the photovoltaic device 100. The portion of the collection film 104 can function as a light pipe without any prismatic features. The amount of light that can be collected and guided through the light collecting film can depend on the geometry, type and density of the prismatic features. The amount of light collected may also depend on the refractive index of the light guide material, which determines the numerical aperture.

In this way, light is guided through the light collecting film 104 by total internal reflection (TIR). Any particular light ray can be oriented at an angle to the top or bottom surface, while pure redirection is parallel to the plane where light is generally incident from the direction of incidence into the main (top or bottom) plane of the film. It is made in the transverse direction toward the edge portion 110 of one film 104. Guided light may experience losses due to absorption in the collection film and scattering from other facets. In order to reduce this loss in the guided light, it is desirable to limit the transverse length of the condensing film 104 to tens of inches or less to reduce the number of reflections. However, limiting the length of the light collecting film 104 can reduce the area over which light is received. Thus, in some embodiments, the length of condensing film 104 can be increased to greater than tens of inches. In some other embodiments, optical coatings may be deposited on the surface of light collecting film 104 to reduce Fresnel loss.

When light rays impinge on a portion of the collection film 104, typically the majority of the film surface, without the prismatic features 108, it can be transmitted through the collection film but cannot be turned into that collection film. In the embodiments described below, where it is desirable to allow a substantial portion of the incident incident through the film to be transmitted, the transmitted light can illuminate the active display. Nevertheless, it may be desirable to tune the redirected amount of light to increase the focusing of the photovoltaic device 100. In order to increase the amount of light shunted toward the photovoltaic device 100, several light collecting film layers comprising prismatic features that are offset (ie misaligned) with respect to each other, as illustrated in FIG. 11D. It may be advantageous to stack them. FIG. 11D illustrates one embodiment that includes a first light collecting film layer 204 with prismatic features 208 and a second light collecting film layer 212 with prismatic features 216. The photovoltaic device 200 is disposed in the transverse direction with respect to the two light collecting film layers 204 and 212. Prism features 208 and 216 are designed to be randomized or offset relative to one another to have a high probability of mismatch of light-turning features. Light ray 220 is turned and guided through first condensing film 204 as described above. Light rays 224 passing through the first light collecting film 204 at point A are redirected and guided through the second light collecting film 212. Offsetting prismatic features 208, 216 in this manner reduces the spacing between the components, increasing the density of the prismatic features. Offsetting the components may increase the electrical output of the photovoltaic device (at the expense of transmitted light) by increasing the amount of light optically coupled to the photovoltaic device. Since the light collecting film layers 204 and 212 can be thin, it is possible to increase the amount of light coupled to the PV cell by stacking a plurality of light collecting film layers. The number of layers that can be stacked together depends on the size and / or thickness of each layer and on each other, in addition to the allowable loss of transmitted light for the intended use (eg, viewing the display through the layers). Depends on Fresnel loss at the interface. In some embodiments, two to ten light collecting film layers may be stacked on each other.

The advantage of using a prism light guide plate, sheet or film (or film) to focus, focus and direct light towards the photovoltaic device is that fewer photovoltaic devices may be needed to achieve the desired electrical output. . Thus, this technique could possibly reduce the cost of generating energy by the photovoltaic device. Another advantage is the ability to focus light for generating power without undue reduction in transmission of light to or from a reflective display.

12 illustrates another light collecting film in which the light-turning features further include diffractive features 308 rather than prismatic features. In various preferred embodiments, the diffractive features 308 change the direction of light (eg, light ray 312) incident on the light collecting film 104 at an angle, through which light is collected. Propagates from the edge 110 of the light collecting film 104 and into the photovoltaic device 100. Light is, for example, through total internal reflection along the length of the light collecting film 104, for example at a grazing angle of greater than about 40 ° (measured from perpendicular to the surface of the light collecting film 104). It can be propagated. This angle may be a critical angle established by Snell's law or above that critical angle. The diffracted light rays 312 are redirected at approximately right angles to the length of the light collecting film 104. Diffractive features 308 may include surface or volume diffractive features. Diffractive features 308 may be included on the diffractive redirecting film on the first side 103 of the light collecting film 104. The diffractive features may comprise holographic features. Likewise, the diffractive redirecting film may comprise a holographic or holographic film in some embodiments. Depending on the relative refractive index or reflectance of the material, the diffractive microstructures can be on the top, bottom or side portions of the light collecting film 104.

13A and 13B illustrate an embodiment of a light collecting film 240 that includes another kind of light-turning element 242. Light-turning element 242 may be a microstructured thin film. In some embodiments, light-turning element 242 can include volumetric or surface diffractive features or holograms. Light-turning element 242 may be a thin plate, sheet or film. The thickness of the light-turning element 242 may range from about 1 μm to about 100 μm in some embodiments, but may be larger or smaller. In some embodiments, the thickness of the light-turning element or layer 242 can be between 5 μm and 50 μm. In some embodiments, the thickness of the light-turning element or layer 242 may be between 1 μm and 10 μm. The light-turning element 242 can be attached to one layer on the substrate 244 of the light collecting film 240 by an adhesive. The adhesive may be index-matched with the material comprising the substrate 244. In some embodiments, the adhesive may be index matched with the material comprising the light-turning element 242. In some embodiments, the light-turning element 242 can be stacked on the substrate 244 to form the light collecting film 240. In certain other embodiments, volumetric or surface diffractive features or holograms may be formed on the top or bottom surface of the substrate 244 by deposition or other processes.

Volumetric or surface diffractive elements or holograms can operate in either transmission or reflection mode. Transmissive diffractive elements or holograms generally comprise optically transmissive materials and diffract light passing through them. Reflective diffractive elements and holograms generally comprise a reflective material and diffract light reflected therefrom. In certain embodiments, the volume or surface diffraction element / hologram may be a hybrid of transmission and reflection structures. Diffractive elements / holograms may include rainbow holograms, computer-generated diffractive elements or holograms, or other types of holograms or diffractive optical elements. In some embodiments (eg, on the back side of the display), it may be desirable for the reflective hologram to be above the transmissive hologram, because a high proportion of incident light is directed to the photovoltaic device (and in some embodiments the light source). This is because the reflective hologram can condense and guide white light better than the transmissive hologram. In these embodiments (eg on the front side of the display), transmissive holograms can be used if higher transparency is desired. Transmissive holograms may be preferred over reflective holograms in embodiments that include multiple layers. In certain embodiments described below, the laminate of the transmissive layer is particularly useful for increasing optical performance. As is well known, the transmissive layer can be useful for embodiments where the light collecting film lies on the front of the display, so that a high percentage of incident light can pass through or from the display below the light collecting film. have.

One possible advantage of the light-turning element 242 is described below with reference to FIGS. 13A and 13B. FIG. 13A illustrates an embodiment in which the light-turning element 242 includes a transmissive hologram and is disposed on an upper surface of the substrate 244 to form a light collecting film 240. Light rays of ambient light 246i are incident on the top surface of light-turning element 242 at incident angle θ ₁ . Light redirecting element 242 redirects or diffracts incident light 246. Since diffracted light beam 246r is incident on substrate 244, the propagation angle of light beam 246r on substrate 244 is θ ″ ₁ greater than θ _TIR . Thus, light-turning element 242 Light 246r transmitted from condensing film 240 without being transversely guided in substrate 244 in the absence of light is now condensed in condensing film 240 in the presence of light-turning element 242 and guided laterally The light-turning element 242 can thus increase the light collecting efficiency of the light collecting film 240. Conversely, light from the light source at the edge of the film 240 is more likely to be diverted toward the top surface. .

13B illustrates an embodiment in which the light-turning element 242 includes a reflective hologram and is disposed on the bottom surface of the substrate 244. The light ray 248 is incident on the upper surface of the light collecting film 240 at an angle θ ₁ such that the refractive angle of the light ray 248 is θ ′ ₁ . When impinging on the light-turning element 242, the refracting ray 248r is reflected by the light-turning element 242 as light beam 248b at an angle θ ″ ₁ greater than the critical angle θ _TIR relative to the substrate 244. Since angle θ ″ ₁ is greater than the critical angle θ _TIR , light ray 248b is then guided in condensing film 240 through multiple total internal reflections. In this manner, light rays 248i that are not guided by substrate 244 are guided in condensing film 240 because there is now light-turning element 242. Conversely, light from the light source at the edge of the light collecting film 240 is more likely to be diverted toward the upper surface.

FIG. 14 illustrates one embodiment of a display device 85 in which a light collecting film 80 is disposed on a front display surface of an array of active pixels for a reflective display 82. In the illustrated embodiment, the reflective display 82 includes an active MEMS array, in particular an active interferometric modulator (IMOD) with individually addressable pixels arranged in the array, as described above with respect to FIGS. 1-7E. Include. In other embodiments, reflective display 82 may include LCD, DLP or electrophoretic active display technology. The reflective display 82 shown in FIG. 14 includes a front display surface to which the light collecting film 80 is attached. The front display surface is connected to the back plate 87 by a spacer 300 and / or a seating frit surrounding the array 82 of display pixels. The array 82 includes a substrate 20, an optical stack 16 including a stationary (transparent) electrode, and a movable electrode or mirror 14 connected to the substrate 20 by a support 18. . For purposes of illustration, the IMOD array in FIGS. 14 and 15 is schematically represented by a single IMOD.

In the embodiment of FIG. 14, the front condensing film 80 includes a front condensing film surface 80a, a rear condensing film surface 80b, and at least one edge portion 88. The photovoltaic element 86 is disposed on the edge 88 of the light collecting film 80, and the light source 90 is located adjacent to the photovoltaic element 86 or other edge position. The front condensing film surface 80a receives ambient light 95. The light-turning features 94 of the light collecting film 80 are directed towards the edge 88 of the light collecting film 80 to receive ambient light 95 and convert it into electrical energy by the photovoltaic device 86. To face. The light source 90 is directed toward the reflective display 82 to illuminate the display 82 in the absence of sufficient ambient light 95 or to brighten the reflective display 82 with the ambient light 95. The diverting features 94 can direct light. In some embodiments, the light source 90 can be omitted.

FIG. 15 illustrates another embodiment of a reflective display device 85 in which like elements are denoted by like reference numerals, wherein the light collecting film has a front light collecting film surface 84a and a back light collecting film surface 84b. An 84 is disposed behind the array of active pixels for the display 82. The ambient light 95 passes through the support 18 or other transparent inactive area between the active areas of the display 82 to be received by the front light collecting film face 84a of the back light collecting film 84. The light-turning features 94 of the light collecting film 84 direct light 95 towards the edge 88 of the light collecting film 84 to be converted into electrical energy by the photovoltaic device 86.

16 illustrates a top view of an array of display pixels 161 for reflective display 82. The display pixels 161 are arranged in rows 162 and columns 163. The area or inactive area between row 162 and column 163 includes support 18 and gap 164. Typically, inactive regions such as support 18 and gap 164 are masked with a black mask to minimize reflections from these regions, minimize the contrast ratio of display pixels 161, and improve performance. have. In some embodiments of the invention in which the display pixels 161 are reflective, light passes rearward through the pillars 18 and the gaps 164 between the rows 162 and columns 163 of the reflective display 82. Can pass through the light collecting film 84. The light-turning features may be aligned with the inactive area to minimize light collection or illumination, depending on whether it is on the front side or the back side of the display 82. Thus, the black mask can typically be removed as the light absorbed by the black mask is instead diverted to the photovoltaic device 86 on the edges of the light collecting films 80, 84. In this way, loss of reflection and contrast from these areas is reduced, while light received in these areas can be used to generate power. By eliminating the black mask material, black mask deposition and patterning steps, the overall cost of manufacturing the display device 85 can be reduced. When the light collecting film 84 is on the back side (FIG. 15), openings 165 may be formed as electrode strips in the gaps 164 between rows or columns to increase transmission of light. 16 illustrates an IMOD example where the row electrodes 162 are transparent, so only the reflective column electrodes 163 fill the gap 164 between the rows 162 with the column electrodes 163. It is necessary to have the opening 165 at the crossing position. The column electrode 163 of FIG. 16 corresponds to the movable electrode or mirror 14 of FIGS. 14 and 15, while the row electrode 162 of FIG. 16 is the optical stack 16 of FIGS. 14 and 15. (With a stop transparent electrode included).

FIG. 17A schematically illustrates a transflective display 82 ′ in which some light passes through the display 82 ′ and some light is actively reflected from the pixels of the display 82 ′ and have. In certain embodiments, the proportion of visible light passing through the active array of display pixels ranges from about 5% to about 50%. The display 82 ′ illustrated in FIG. 17 includes a substrate 170, an absorber layer 171, an optical resonant cavity 172, a partial reflector layer (hereinafter simply referred to as a “reflector layer”) 173. ) And an array of transparent interferometric modulators (IMODs) shown in the figure by a single IMOD comprising a light source 174. Substrate 170 is at least partially optically transparent. The absorber layer 171 is positioned under the substrate 170, and the absorber layer 171 is partially optically transmissive. The partial reflector layer 173 is positioned below the substrate 170 and is spaced apart from the absorber layer 171, and the absorber layer 171 is located between the substrate 170 and the partial reflector layer 173. The partial reflector layer 173 can move in the optical cavity 172 in accordance with the IMOD description above. The reflector layer 173 is also partially reflective and partially transmissive. The light source 174 is positioned relative to the substrate 170 such that the absorber layer 171 and the reflector layer 173 are positioned between the substrate 170 and the light source 174. Although not shown, the backplate may be positioned between the partial reflector layer 173 and the backlight 174.

In certain embodiments, the light emitted from the display 82 'in the first direction 175 includes light in the first portion, light in the second portion and light in the third portion. The light of the first portion is incident on the substrate 170 to pass through the substrate 170, passes through the absorber layer 171, is reflected by the reflector layer 173, and passes through the absorber layer 171 to transmit the substrate ( It passes through 170 and is emitted from the substrate 170 in the first direction 175. The light of the second portion is incident on the substrate 170 to transmit the substrate 170, is reflected by the absorber layer 171, and passes through the substrate 170 to transmit the substrate 170 in the first direction 175. ) Is released. The light of the third portion is incident from the light source 174 to the reflector layer 173, passes through the reflector layer 173, passes through the absorber layer 171, passes through the substrate 170, and then passes through the first direction 175. Is emitted from the substrate 170.

In certain embodiments, the substrate 170 comprises a glass or plastic material. In certain embodiments, the absorber layer 171 comprises chromium. In certain embodiments, the reflector layer 173 comprises a metal layer (eg, an aluminum layer having a thickness of 300 kPa or less). In certain embodiments, the transmittance of the reflector layer 173 depends on the thickness of the reflector layer 173.

For the illustrated transflective IMOD, at least one of the absorber layer 171 and the reflector layer 173 may include an absorber layer 171 and a reflector layer such that two optical states are generated by selectively using the principle of interferometry. It is selectively movable to change the spacing between 173). In certain embodiments, display device 85 includes an operable element (eg, pixel or subpixel) of a display system.

In certain embodiments, the light of the first portion and the light of the second portion interfere to produce light having a first color, in accordance with normal IMOD operation described with respect to FIGS. 1-7E. The first color depends on the size of the optical cavity, which can be changed between at least two states.

In certain embodiments, the light source 174 can selectively change the color of the interferometric sum of the light of the first portion and the light of the second portion. The light source 174 may be turned on to form a third state that produces a different color. However, different colors can be produced in the absence of ambient light.

In certain embodiments, the display device 85 can be viewed from both the first direction 175 and the second direction 176 generally opposite to the first direction. For example, the display device 85 of this certain embodiment can be seen from a first position on the first side of the display device 85 and from a second position on the second side of the display device 85. In certain embodiments, the light emitted from the display device 85 in the second direction 176 includes light of the fourth portion, light of the fifth portion, and light of the sixth portion. In certain embodiments, the light of the fourth portion is incident on the substrate 170 to pass through the substrate 170, passes through the absorber layer 171, and is reflected by the reflector layer 173 to be reflected in the second direction 176. Is emitted from the display device 85. In certain embodiments, the light of the fifth portion is incident on the reflector layer 173, passes through the reflector layer 173, is reflected from the absorber layer 171, and passes through the reflector layer 173 to display the display device 85. ) Is released. In certain embodiments, the light of the sixth portion is incident on the reflector layer 173, is reflected from the reflector layer 173, and is emitted from the display device 85 in the second direction 176. In certain embodiments, the light of the fifth portion includes light emitted by the light source 174 and the light of the sixth portion includes light emitted by the light source 174. On the front side, additional color states can be viewed from the rear or second direction 176, depending on whether the backlight 174 is on or off and whether ambient light is present.

Referring to FIG. 17B, the backlight of FIG. 17A is received from the light source 90 (eg, injected along the edge 88 of the light collecting film 84), and guides light along the light collecting film 84, It can be replaced by a back collecting film 84 that provides back side illumination by emitting light towards the pixels of the transflective display 82 '. Condensing film 84 disrupts propagation of light within condensing film 84 such that it is uniformly emitted across the front face 84a of rear condensing film 84 towards the front face of display 82 '. ) Or redirecting features located on or on the light collecting film 84. In addition, additional color states may be created by front illumination from light source 90 with front condensing / lighting film 80 on the front side of transflective IMOD display 82 '. The photovoltaic element 86 may be provided on the front side or rear side light collecting films 80 and 84.

18 illustrates one embodiment of a display device 85 having a front condensing film 80 disposed on a front display surface 82a of a light emitting display 82 ″. Pixels of the display 82 ″ May be emissive, such as LCD, LED, OLED, FED technology, etc., or the display 82 "includes a backlight. In some embodiments, the display pixel is such that some light passes through an active pixel region of the display 82". Semi-reflective, such as the backlit IMODs of FIG. 17A or FIG.

The ambient light 95 is received by the front condensing film surface 80a of the front condensing film 80 and passes through the light-turning features 94 to the edge 88 of the condensing film 80. The element 86 is converted into electrical energy. Light emitted from the emissive display 82 "is received by the rear condensing film surface 80b of the front condensing film 80. The light-turning features 94 are formed at the edges of the condensing film 80; The light is directed toward 88 and converted into electrical energy by photovoltaic element 86. Light from emissive display 82 " 85 may be illuminated.

19 illustrates one embodiment of a display device 85 in which a back light collecting film 84 is positioned below a light emitting display 82 ". As illustrated, the back light collecting film 84 is a light source 90. And functions as both a light receiving unit and a backlight, similarly to the transflective IMOD 82 'of Fig. 17B. A light emitting display 82 " Likewise, any backlit active display technology can be used.

As can be seen in FIG. 19, the ambient light 95 passes through the display 82 ″ through the light-turning features 94 from the front light collecting film face 84a of the back light collecting film 84. It is converted into electrical energy by the photovoltaic element 86 toward the edge 88 of the back light collecting film 84. The light source 90 is disposed on the edge 88 of the back light collecting film 84 The light emits light, which is directed towards the display 82 ″ describing the light-turning features 94 to illuminate the display 85.

20 illustrates a back condensing film 84 disposed between a light emitting display 82 "and a back light 174 for the light emitting display 82". Ambient light 95 passes through display 82 "and is received by front condensing film surface 84a of back condensing film 84, through back-converging features 94, back condensing film 84 Toward the edge 88, is converted into electrical energy by the photovoltaic element 86. The back light 174 emits light, and the light is back-collecting film surface of the back light collecting film 84 ( 84b), by the photo-turning features 94, also towards the edge 88 of the back light collecting film 84 by the photovoltaic element 86 (or on different PV on different edges). Element) into electrical energy. The back light 174 also illuminates the display 85 by directing light through the display 82 ". Placing the condensing film 84 between the emissive display 82 "and the back light 174 and aligning the light-turning features with the inactive area of the display 85 is indicated as ambient light 95. It can replace the black mask on the pixels 161, and the emitted light is split into photovoltaic elements 86 at the edges of the condensing film 84 and converted into electrical energy, thereby reflecting or reflecting from the inactive region to the viewer. Reduce the transmitted light The function of the black mask to reduce color fading (i.e. increase the contrast for the active pixel) can be met by the light collecting film while generating power and forming the black mask As described above, removal of the black mask can reduce overall processing cost and manufacturing time.

FIG. 21 illustrates an embodiment with a front condensing film 80 disposed above reflective display 82. As illustrated in this embodiment, the front condensing film 80 includes asymmetric light-turning features 108, such as those of FIG. 11C. Ambient light 95 is received by front condensing film surface 80a of front condensing film 80 toward one edge 88 of condensing film 80 via light-turning features 108. Towards the surface, the photovoltaic element 86 is converted into electrical energy. The light source 90 is positioned at the other opposite edge of the front condensing film 80 to emit light, which light is displayed by the light conversion features 108 to illuminate the display 85. 82).

While the foregoing detailed description discloses several embodiments of the present invention, it is to be understood that the present disclosure is exemplary only and is not intended to limit the present invention. It is necessary to recognize that the specific forms and operations disclosed may differ from those described above and that the methods described herein may be used in other contexts than the fabrication of semiconductor devices.

14: movable electrode or mirror 16: optical stack
18: support or column 20: substrate
80: condensing film 80a: front condensing film surface
80b: rear condensing film surface 87: back plate
86: photovoltaic device 88: edge
300: spacer 90: light source
94: light-turning structure 95: ambient light

Claims (44)

An active array of display pixels having a front display surface facing the viewer and a back display surface;
A front condensing film surface, a rear condensing film surface, at least one edge and a plurality of light-turning features, respectively, each of which is adjacent to either the front display surface or the rear display surface. At least one collection film; And
A photovoltaic device disposed on an edge of the light collecting film and oriented to receive light transversely transmitted through the light collecting film surface from the light-turning features;
And the light-turning features are configured to redirect light between the front or rear light collecting film surface and an edge of the light collecting film. The display device of claim 1, further comprising a light source disposed on an edge of the light collecting film. The display device of claim 2, wherein the light source comprises a light-emitting diode (LED). The display device of claim 1, wherein the light source is disposed on the same edge as the photovoltaic device. The display device of claim 1, wherein the light source is disposed at a position different from that of the photovoltaic device. The display device of claim 1, wherein the light collecting film comprises a thin film having a thickness of about 0.5 mm to 10 mm. 10. The method of claim 1, further comprising a plurality of light collecting films disposed in a laminated structure, wherein each light collecting film includes a front light collecting film surface, a back light collecting film surface, at least one edge portion, and a plurality of light-turning features. And the light-turning features are configured to redirect light between the front or rear light collecting film surface and an edge of the light collecting film. The display device of claim 1, wherein the light-turning features of the light collecting film comprise prismatic features. The display device of claim 8, wherein the prismatic features are symmetrical. The display device of claim 8, wherein the prismatic features are asymmetric. The display device of claim 10, wherein the prism component comprises a slit. The photovoltaic device of claim 10, wherein the photovoltaic device and the light source are disposed on opposing edges of the light converging film, wherein the asymmetric prism components of the light converging film direct ambient light from the front light condensing film surface to the photovoltaic device. And direct light emitted from the light source toward the back light collecting film surface. The display device of claim 1, wherein the light-turning feature comprises a diffractive feature. The display device of claim 1, wherein the light-turning feature comprises a holographic feature. The display device of claim 1, wherein the pixels of the active array of display pixels use reflective display technology. The display device of claim 15, wherein the pixels of the active array of display pixels contain microelectromechanical systems (MEMS) elements. The display device of claim 16, wherein the MEMS element is an interferometric modulator (IMOD). 16. The display device of claim 15, wherein the pixels of the active array of display pixels contain liquid crystal display (LCD) elements. The display device of claim 15, wherein the light collecting film is disposed on a front display surface of the active array of display pixels. The display device of claim 15, wherein the light collecting film is disposed on a rear display surface of the active array of display pixels. The display device of claim 20, wherein a second light collecting film is disposed on a front display surface of the active array of display pixels. 21. The display device of claim 20, wherein ambient light can pass through at least one inactive area between active display areas of the array. The display device of claim 22, wherein the pixels of the active array of display pixels are transflective and a portion of the ambient light passes through the active pixel regions to reach the light collecting film. The display device of claim 22, wherein the inactive area comprises an area between pixels. The display device of claim 22, wherein a ratio of about 5% to about 50% of visible light can pass through the active array of display pixels. The display device of claim 1, wherein the pixels of the active array of display pixels use an emissive display technology. 27. The display device of claim 26, wherein the pixels of the active array of display pixels utilize a display technology selected from the group consisting of LED, OLED, FED and backlit reflective technologies. 28. The display device of claim 27, wherein the pixels of the active array of display pixels contain organic light emitting diode (OLED) elements. 27. The display device of claim 26, wherein the pixels of the active array of display pixels contain liquid crystal display (LCD) elements. 27. The display device of claim 26, wherein the light collecting film is disposed on a front display surface of the active array of display pixels. 27. The display device of claim 26, wherein the light collecting film is disposed on a rear display surface of the active array of display pixels. 32. The display device of claim 31, wherein a second light collecting film is disposed on a front display surface of the active array of display pixels. An array of display pixels;
At least one light collecting film disposed after the array of display pixels;
At least one photovoltaic element disposed at a first edge portion of the light collecting film; And
At least one light source disposed in the second edge portion,
The light collecting film has a plurality of light-turning features, the light-turning features being configured to redirect light between the front or rear light-collecting film surface and the edges of the light-collecting film,
The photovoltaic device is oriented to receive light transmitted transversely through the light converging film surface from the light-turning features;
And the light source emits light transversely through the light collecting film to be redirected by the light-turning features toward the array of display pixels. Image display means for displaying and changing an image;
Optical energy conversion means for converting optical energy into other forms of energy; And
And light-direction switching means for redirecting light in the transverse direction along the display surface from the direction incident on the image display means toward the light energy conversion means. 35. The display device of claim 34, further comprising means for emitting light. 35. The display device according to claim 34, wherein the image display means includes an active array of display pixels including a front display surface, a rear display surface and at least one edge portion. 35. The display device according to claim 34, wherein the optical energy conversion means includes a photovoltaic element. 35. The apparatus of claim 34, wherein the light-directing means comprises a light collecting film having a front light collecting film surface, a back light collecting film surface and a plurality of light-turning features, the light-turning features being the front Or redirect the light between the rear light collecting film surface and an edge of the light collecting film. Actively displaying an image in an image area;
Focusing light from the image area;
Redirecting light from the image area to at least one edge of the image area; And
And converting light into electric current. 40. The method of claim 39, further comprising emitting light from an edge of the image area to redirect the light to the image area. 40. The method of claim 39, wherein actively displaying comprises moving a microelectromechanical system (MEMS) mirror. 40. The method of claim 39, wherein the image region comprises an array of display pixels operatively coupled to at least one light collecting film. Operatively coupling a light collecting film having a front light collecting film surface, a back light collecting film surface, at least one edge portion and a plurality of light-turning features to a front or rear display surface of an active array of display pixels; And
The photovoltaic device is coupled with the edge of the light collecting film such that ambient light is directed by the light-turning features to the photovoltaic device at the edge of the light collecting film from the front light collecting film surface and converted into electrical energy. A method of manufacturing a display device comprising the step of aligning. The method of claim 43, further comprising disposing a light source that emits light on an edge of the light collecting film.

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