PATENT DOCUMENT

Publication Number: US-8673163-B2
Application Number: US-16370108-A
Country: US
Kind Code: B2

Title: Method for fabricating thin sheets of glass

Abstract:
Fabrication of thin sheets of glass or other substrate material for use in devices such as touch sensor panels is disclosed. A pair of thick glass sheets, typically with thicknesses of 0.5 mm or greater each, may each be patterned with thin film on a surface, sealed together to form a sandwich with the patterned surfaces facing each other and spaced apart by removable spacers, either or both thinned on their outside surfaces to thicknesses of less than 0.5 mm each, and separated into two thin glass sheets. A single thick glass sheet, typically with a thickness of 0.5 mm or greater, may be patterned, covered with a protective layer over the pattern, thinned on its outside surface to a thickness of less than 0.5 mm, and the protective layer removed. This thinness of less than 0.5 mm may be accomplished using standard LCD equipment, despite the equipment having a sheet minimum thickness requirement of 0.5 mm.

Claims:
What is claimed is: 
     
       1. A method for fabricating thin sheets of glass, comprising:
 providing a first sheet of glass having a first thickness; 
 providing a second sheet of glass having a second thickness; 
 patterning a first layer of thin film on a surface of the first sheet of glass; 
 patterning a second layer of thin film on a surface of the second sheet of glass; 
 providing a plurality of spacers between the first and second sheets of glass; 
 joining the first and second sheets of glass together with the patterned first and second layers of thin film facing each other and the spacers distributed between facing surfaces of the first and second sheets of glass along border and interior regions thereof; 
 thinning at least one of the first and second sheets of glass on a side opposite the patterning; and 
 separating the first and second sheets of glass from each other. 
 
     
     
       2. The method of  claim 1 , wherein at least one of the first and second thicknesses is 0.5 mm or greater prior to the thinning. 
     
     
       3. The method of  claim 1 , further comprising:
 forming a third layer of thin film on a surface of the first sheet of glass after thinning, the third layer formed as a complete, unpatterned layer of the same material used in forming the patterned first or second layers. 
 
     
     
       4. The method of  claim 1 , wherein the joining comprises sealing the edges of the first and second sheets of glass together. 
     
     
       5. The method of  claim 1 , wherein the thinning comprises thinning the at least one of the first and second sheets to less than 0.5 mm. 
     
     
       6. The method of  claim 1 , wherein the thinning comprises at least one of chemical etching and mechanical polishing. 
     
     
       7. The method of  claim 3 , further comprising:
 after thinning, forming a fourth layer of thin film on a surface of the second sheet of glass the fourth layer being a complete, unpatterned layer of the same material used in forming the first or second layers. 
 
     
     
       8. The method of  claim 1 , wherein the separating comprises unsealing sealed-together edges of the first and second sheets of glass. 
     
     
       9. The method of  claim 1 , wherein the separating comprises removing spacers forming space between the first and second sheets of glass.

Description:
FIELD OF THE INVENTION 
     This relates generally to the fabrication of thin sheets of substrate material, and more particularly, to the fabrication of thin sheets of glass. 
     BACKGROUND OF THE INVENTION 
     The standard process for fabricating LCD panels involves, inter alia, sealing two transparent substrates together to form a sandwich for depositing liquid crystal therebetween, thinning the sandwich to an appropriate LCD panel thickness, and depositing thin film on the outside surfaces of the sandwich. Conventional substrates are made from sheets of glass or some other transparent material. In order to withstand the chemical and mechanical rigors of fabrication without deformation or damage, a conventional sheet is generally at least 0.5 mm thick. Because 0.5 mm is the thinnest dimension for the sheets being used, standard LCD fabrication equipment has been designed to have a minimum thickness tolerance of 0.5 mm. This means that any sheet fabricated using standard LCD technology should have a thickness of at least 0.5 mm in order to be handled properly. 
     In recent years, touch sensor panels, touch screens, and the like have become available as input devices. Touch screens, in particular, are becoming increasingly popular because of their ease and versatility of operation as well as their declining price. Touch screens can include a touch sensor panel, which can be a clear panel with a touch-sensitive surface, and a display device, such as an LCD panel, that can be positioned partially or fully behind the touch sensor panel so that the touch-sensitive surface can cover at least a portion of the viewable area of the display device. Touch screens can allow a user to perform various functions by touching the touch sensor panel using a finger, stylus or other object at a location dictated by a user interface (UI) being displayed by the display device. In general, touch screens can recognize a touch event and the position of the touch event on the touch sensor panel, and a computing system can then interpret the touch event in accordance with the display appearing at the time of the touch event, and thereafter can perform one or more actions based on the touch event. 
     Like LCD panels, touch sensor panels in touch screens may be made of glass or other suitable transparent material. However, unlike LCD panels, touch sensor panels may be generally very thin, much more so than LCD panels. Fabrication technology can be similar for both touch sensor panels and LCD panels. However, due to touch sensor panel thinness, difficulties can occur in fabricating them using the same equipment as that used for LCD fabrication because the touch sensor panels may not fit the equipment and/or may be too fragile to withstand the rigors of the fabrication process. As such, equipment specifically designed for fabricating touch screen panels may be needed, which can be very expensive. 
     SUMMARY OF THE INVENTION 
     This relates to the fabrication of thin sheets of glass or other substrate material for use in devices such as touch sensor panels. In some embodiments, fabrication can be achieved using standard LCD technology. Standard equipment for fabrication of LCD panels has been designed with a minimum thickness tolerance of 0.5 mm. This is because glass (or other transparent material) used to fabricate LCD panels should be at least 0.5 mm thick in order to withstand the rigors of fabrication. Thinner glass would be subject to deformation or damage. 
     To fabricate thin sheets of glass, a pair of thick glass sheets may be provided, typically with thicknesses of 0.5 mm or greater each. Patterns of thin film may be deposited on a surface of each glass sheet for use as conductive traces, anti-reflective material, and/or protective layering, for example. The pair of thick glass sheets may be sealed together to form a sandwich with their patterned surfaces facing each other and separated by removable spacers. Either or both of the sandwiched thick glass sheets may be thinned on their respective outside surfaces to thicknesses of less than 0.5 mm each. The sandwich of now thin glass sheets may be separated from each other. Either or both sheets may have thicknesses less than the minimum thickness requirement for standard LCD equipment, yet be fabricated using that same equipment. 
     To fabricate thin sheets of glass, a thick glass sheet may be provided, typically with a thickness of 0.5 mm or greater. Patterns of thin film may be deposited on a surface of the glass sheet for use as described previously. A removable protective layer may be placed over the patterned thin film. The thick glass sheet may be thinned on its outside surface opposite the protective layer surface to a thickness of less than 0.5 mm. The protective layer may be removed. The sheet may have a thickness less than the minimum thickness requirement for standard LCD equipment, yet be fabricated using that same equipment. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1   a  illustrates an exemplary pair of thick glass sheets patterned with thin film on a surface according to embodiments of the invention. 
         FIG. 1   b  illustrates an exemplary pair of thick glass sheets which are sealed together with their patterned surfaces facing each other and separated by spacers to form a sandwich according to embodiments of the invention. 
         FIG. 1   c  illustrates an exemplary sandwich of patterned glass sheets which has been thinned on outside surfaces according to embodiments of the invention. 
         FIG. 1   d  illustrates an exemplary sandwich of thin patterned glass sheets which has been coated with thin film on outside surfaces according to embodiments of the invention. 
         FIG. 1   e  illustrates an exemplary pair of thin glass sheets which are coated with thin film on one surface and patterned with thin film on the opposite surface according to embodiments of the invention. 
         FIG. 2  illustrates an exemplary method for fabricating a pair of thin glass sheets according to embodiments of the invention. 
         FIG. 3   a  illustrates an exemplary thick glass sheet patterned with thin film on a surface according to embodiments of the invention. 
         FIG. 3   b  illustrates an exemplary thick glass sheet patterned with thin film on a surface and with a protective layer of material overlaying the thin film pattern according to embodiments of the invention. 
         FIG. 3   c  illustrates an exemplary thick glass sheet patterned with thin film on a surface and with a protective layer of material overlaying the thin film pattern, where the outside surfaces of the sheet and the layer have been thinned according to embodiments of the invention. 
         FIG. 3   d  illustrates an exemplary thin patterned glass sheet with a thin protective layer of material thereon, where the sheet has been coated with thin film on the outside surface according to embodiments of the invention. 
         FIG. 3   e  illustrates an exemplary thin glass sheet which is coated with thin film on a surface and patterned with thin film on the opposite surface according to embodiments of the invention. 
         FIG. 4  illustrates an exemplary method for fabricating a thin glass sheet according to embodiments of the invention. 
         FIG. 5   a  illustrates an exemplary digital media player having a touch sensor panel that includes a thin glass sheet according to embodiments of the invention. 
         FIG. 5   b  illustrates an exemplary mobile telephone having a touch sensor panel that includes a thin glass sheet according to embodiments of the invention. 
         FIG. 6  illustrates an exemplary computing system including a touch sensor panel utilizing a thin glass sheet according to embodiments of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the following description of preferred embodiments, reference is made to the accompanying drawings which form a part hereof, and in which it is shown by way of illustration specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the preferred embodiments of the invention. 
     This relates to the fabrication of thin sheets of glass or other substrate material for use in devices such as touch sensor panels. In some embodiments, fabrication can be achieved using standard LCD technology. Standard equipment for fabrication of LCD panels has been designed with a minimum thickness tolerance of 0.5 mm. This is because glass (or other transparent material) used to fabricate LCD panels should be at least 0.5 mm thick in order to withstand the rigors of fabrication. Thinner glass would be subject to deformation or damage. 
     Touch sensor panels may be significantly thinner than LCD panels, but use similar fabrication methods. Therefore, using standard LCD technology to fabricate touch sensor panels may substantially save time, cost, and labor. However, to do so, the touch sensor panels should meet the minimum thickness tolerance of LCD equipment. One way to do so may be by forming a sandwich of two sheets such that the combined thickness of the sandwich during fabrication does not drop below 0.5 mm. As such, each sheet in the sandwich can be thinned during fabrication to a thickness of less than 0.5 mm. Another way to do so may be by applying a protective layer to a sheet such that the combined thickness during fabrication does not drop below 0.5 mm. As such, the sheet can be thinned during fabrication to a thickness of less than 0.5 mm. After thinning, the sheets can be separated, resulting in separate sheets that are thinner than could be achieved had the sandwich not been formed. This process can result in thin glass sheets suitable for touch sensor panels. Moreover, for the pairs of sheets, the throughput may increase substantially because two thin sheets may be processed at once. 
     Although embodiments of this invention are described and illustrated herein in terms of touch sensor panels with glass substrates, it should be understood that embodiments of this invention are not so limited to such panels and substrates, but is generally applicable to panels utilizing other touch and proximity sensing technologies, and any substrate for which thinness is required. 
       FIG. 1   a  illustrates an exemplary pair of thick glass sheets patterned with thin film on a surface according to embodiments of the invention. In the example of  FIG. 1   a , thick glass sheet  100 - a  may have a thickness of d 1a  and thick glass sheet  100 - b  may gave a thickness of d 1b . Thicknesses d 1a  and d 1b  may or may not be the same. Conventional thick glass sheets may typically be 0.5 mm thick or greater. 
     Patterns of thin film  105 - a  may be deposited on a surface of glass sheet  100 - a . Similarly, patterns of thin film  105 - b  may be deposited on a surface of glass sheet  100 - b . The thin film patterns may be used as conductive traces for carrying signals and may include transparent materials, such as indium tin oxide (ITO). Alternatively or additionally, the thin film patterns may be used as an anti-reflective layer to minimize reflection off the glass sheet surface and may include anti-reflective material. Alternatively or additionally, the thin film patterns may be used as a protective layer and may include ceramic material or any other material with similar protective properties. The type of thin film used may depend on the ultimate use of the fabricated thin glass sheet. 
       FIG. 1   b  illustrates an exemplary pair of thick glass sheets which are sealed together with their patterned surfaces facing each other and separated by spacers to form a sandwich according to embodiments of the invention. In the example of  FIG. 1   b , thick glass sheets  100 - a  and  100 - b  of  FIG. 1   a , for example, may be temporarily joined together at their edges using any known method for doing so. For example, the edges of glass sheets  100 - a  and  100 - b  may be laminated together using any known laminate. Glass sheets  100 - a  and  100 - b  may be joined together with their patterned surfaces facing each other. Removable spacers  110  may be placed between the patterned surfaces to keep them apart. Spacers  110  may include any material that can maintain space between glass sheets  100 - a  and  100 - b  and that does not interact with the glass sheets and patterns  105 - a  and  105 - b . Alternatively, a removable sealant may be placed between the patterned surfaces to keep them apart. 
       FIG. 1   c  illustrates an exemplary sandwich of patterned glass sheets which have been thinned on outside surfaces according to embodiments of the invention. In the example of  FIG. 1   c , thick glass sheets  100 - a  and  100 - b  of  FIG. 1   b , for example, that are sandwiched together may be thinned from respective thicknesses of d 1a  and d 1b  to thicknesses of d 2a  and d 2b , where d 2a &lt;d 1a  and d 2b &lt;d 1b . For example, conventional thick glass sheets having thicknesses of 0.5 mm or more each may be thinned to thicknesses of less than 0.5 mm each. The thinning process may include chemical etching, mechanical polishing, a combination of the two, and any other known methods for thinning glass sheets. One or both outside surfaces of the sandwich, i.e., the surfaces of glass sheets  100 - a  and  100 - b  opposite the patterned surfaces, may be thinned. Since patterns  105 - a  and  105 - b  may be sealed within the sandwich on inside surfaces, the patterns may be protected from deformation or damage during the thinning process. As a result of the thinning process, each glass sheet  100 - a  and  100 - b  can have a thickness less than the minimum thickness requirement of 0.5 mm for standard LCD equipment; while the sandwich of the glass sheets maintains a thickness at or above the requirement. 
       FIG. 1   d  illustrates an exemplary sandwich of thin patterned glass sheets which have been coated with thin film on outside surfaces according to embodiments of the invention. In the example of  FIG. 1   d , the thinned outside surfaces of the sandwich of thin glass sheets  100 - a  and  100 - b  of  FIG. 1   c , for example, may be coated with additional thin film material. Thin film coating  115 - a  may coat the thinned surface of glass sheet  100 - a  with a coating layer thickness of d 3a . Thin film coating  115 - b  may coat the thinned surface of glass sheet  100 - b  with a coating layer thickness of d 3b . The thin film material used to coat the thinned outside surfaces of the sandwich of thin glass sheets  100 - a  and  100 - b  may be similar to the thin film material used to form patterns  105 - a  and  105 - b  described above. This can provide double thin filming—the thin film pattern on one surface and the thin film coating on the opposite surface. This coating may be either a complete layer or just a pattern, depending on the particular implementation for the glass sheets. Alternatively, this coating may be optional, thereby providing single thin filming—the thin film pattern on one surface. 
       FIG. 1   e  illustrates an exemplary pair of thin glass sheets which are coated with thin film on one surface and patterned with thin film on the opposite surface according to embodiments of the invention. In the example of  FIG. 1   e , the sandwich of thin glass sheets  100 - a  and  100 - b  of  FIG. 1   d , for example, may be separated to form separate sheets. Thin glass sheet  100 - a  may have a thin film layer  115 - a  on one surface and a thin film pattern  105 - a  on the opposite surface, where the glass sheet may have a thickness of less than 0.5 mm. Similarly, thin glass sheet  100 - b  may have a thin film layer  115 - b  on one surface and a thin film pattern  105 - b  on the opposite surface, where the glass sheet may have a thickness of less than 0.5 mm. Here, both sheets  100 - a  and  100 - b  may have thicknesses less than the minimum thickness requirement for standard LCD equipment, yet have been fabricated using that same equipment. 
     To separate the sandwich to form separate thin glass sheets  100 - a  and  100 - b , the sealed edges of the sheets may be cut from the sandwich and spacers  110  removed. Other mechanical methods may be used to separate the glass sheets. Alternatively, chemical methods may be used, e.g., delamination to remove a laminate that formed the seal. A combination of mechanical and chemical methods may also be used. 
     In an example, as shown in  FIGS. 1   a - 1   e , two thick sheets of glass, each having a thickness of about 0.5 mm could be joined to form a sandwich having a thickness of about 1.0 mm. The sandwich could be thinned to a thickness of about 0.6 mm. After the sandwich is separated, each glass sheet could have a thickness of about 0.3 mm, which would be well below the minimum thickness requirement of standard LCD equipment. 
     It is to be understood that the thickness of a thin glass sheet is not limited to that described here, but may include any thickness below the minimum thickness requirement of the LCD equipment that may be suitable for touch sensor panels or other devices. 
       FIG. 2  illustrates an exemplary method for fabricating a pair of thin glass sheets according to embodiments of the invention. Optionally using standard LCD technology, a standard LCD thin film deposition tool may be used to place a thin film pattern on a surface of a thick glass sheet ( 205 ). The thick glass sheets may have a thickness of 0.5 mm or more each to meet the minimum thickness requirement of standard LCD equipment. This deposition may be repeated for multiple sheets. A standard LCD sealing tool may be used to join a pair of the patterned thick glass sheets together to form a sandwich, with the patterned surfaces facing each other and with removable spacers placed between the patterned surfaces ( 210 ). The sandwich may have a thickness of 1.0 mm or more, which also meets the minimum thickness requirement of standard LCD equipment. A standard LCD thinning tool may be used to thin one or both outside surfaces of the sandwich, where the thicknesses of one or both glass sheets may each be thinned to less than 0.5 mm ( 215 ). Here, the thinned sandwich may have a thickness of 0.5 mm or more, depending on how thin the sheets are fabricated, which still meets the minimum thickness requirement of standard LCD equipment. The standard LCD thin film deposition tool may be used again to coat the thinned outside surface of the sandwich ( 220 ) to complete the standard LCD fabrication process. 
     After completing the standard LCD fabrication process, unlike LCD panels, the sandwich of thin glass sheets may now be separated into separate glass sheets. Any suitable unsealing tool known to those skilled in the art may be used to separate the pair of patterned thin glass sheets into separate glass sheets ( 225 ). The resulting thin glass sheet or sheets may have a thickness of less than 0.5 mm, which is below the minimum thickness requirement of standard LCD equipment, yet still advantageously have been fabricated using that equipment. 
       FIG. 3   a  illustrates an exemplary thick glass sheet patterned with thin film on a surface according to embodiments of the invention. In the example of  FIG. 3   a , thick glass sheet  300  may have a thickness of d 1 . Conventional thick glass sheets may typically be 0.5 mm or greater in thickness. 
     Patterns of thin film  305  may be deposited on a surface of glass sheet  300 . As mentioned previously, the thin film patterns may be used as conductive traces for carrying a signal and may include semiconductor materials. Alternatively or additionally, the thin film patterns may be used as an anti-reflective layer to minimize reflection off the glass sheet surface and may include anti-reflective material. Alternatively or additionally, the thin film patterns may be used as a protective layer and may include ceramic, organic, or any other materials with such protective properties. 
       FIG. 3   b  illustrates an exemplary thick glass sheet patterned with thin film on a surface and with a protective layer of material overlaying the thin film pattern according to embodiments of the invention. In the example of  FIG. 3   b , thick glass sheet  300  of  FIG. 3   a , for example, may have removable protective layer  310  of thickness d 2  overlaying patterns  305  on the surface of the thick glass sheet. Protective layer  310  may be any material that is capable of withstanding the standard LCD fabrication equipment and that does not interact with glass sheet  300  and patterns  305 . The thickness of protective layer  310  may be any value that would ensure that the combined layer and sheet meets the minimum thickness requirement of the standard LCD equipment. For example, the thickness d 2  may be 0.5 mm or more. Protective layer  310  may protect patterns  305  from deformation or damage during the fabrication process. 
       FIG. 3   c  illustrates an exemplary thick glass sheet patterned with thin film on a surface and with a protective layer of material overlaying the thin film pattern, where the outside surfaces of the sheet and the layer have been thinned according to embodiments of the invention. In the example of  FIG. 3   c , thick glass sheet  300  of  FIG. 3   b , for example, may be thinned from a thickness of d 1  to a thickness of d 3 , where d 3 &lt;d 1 . The surface of glass sheet  300  opposite the surface having protective layer  310  may be thinned. For example, conventional thick glass sheets having thicknesses of 0.5 mm or more each may be thinned to thicknesses of less than 0.5 mm each. The thinning process may include chemical etching, mechanical polishing, a combination of the two, and any other known methods for thinning glass sheets. Optionally, protective layer  310  may also be thinned concurrently with glass sheet  300  from a thickness of d 2  to a thickness of d 4 , where d 4 &lt;d 2 . Glass sheet  300  can have a thickness less than the minimum thickness requirement of 0.5 mm for standard LCD equipment; while the combined sheet  300  and layer  310  maintains a thickness at or above the requirement. 
       FIG. 3   d  illustrates an exemplary thin patterned glass sheet with a thin protective layer of material thereon, where the sheet has been coated with thin film on the outside surface of the sheet according to embodiments of the invention. In the example of  FIG. 3   d , the thinned outside surface of thin glass sheet  300  of  FIG. 3   c , for example, may be coated with additional thin film material. Thin film coating  315  may coat the thinned surface of glass sheet  300  with a coating layer thickness of d 5 . The thin film material used to coat the thinned outside surface of thin glass sheet  300  may be similar to the thin film material used to form patterns  305  described above. This may provide double thin filming—the thin film pattern on one surface and the thin film coating on the opposite surface. This coating may be either a complete layer or just a pattern, depending on the particular implementation for the glass sheet. Alternatively, this coating may be optional, thereby providing single thin filming—the thin film pattern on one surface. 
       FIG. 3   e  illustrates an exemplary thin glass sheet which is coated with thin film on a surface and patterned with thin film on the opposite surface according to embodiments of the invention. In the example of  FIG. 3   e , protective layer  310  on thin glass sheet  300  of  FIG. 3   d , for example, may be removed, leaving the thin glass sheet remaining. To remove protective layer  310  from thin glass sheet  300 , any suitable chemical or mechanical method known to those skilled in the art, or combination thereof, may be used that is capable of removing such a layer. Thin glass sheet  300  may have a thin film layer  315  on one surface and a thin film pattern  305  on the opposite surface, where the glass sheet may have a thickness of less than 0.5 mm. Here, sheet  300  may have a thickness less than the minimum thickness requirement for standard LCD equipment, yet have been fabricated using that same equipment. 
     In an example, as shown in  FIGS. 3   a - 3   e , a thick sheet of glass having a thickness of about 0.5 mm could have a protective layer having a similar thickness applied on a surface of the glass to form a combination having a thickness of about 1.0 mm. The glass sheet could be thinned so that the combination has a thickness of about 0.7 mm. Alternatively, the protective layer could concurrently be thinned so that the combination has a thickness of about 0.6 mm. After the protective layer is removed, the glass sheet could have a thickness of about 0.2 mm, which is well below the minimum thickness requirement of standard LCD equipment. 
     It is to be understood that the thickness of a thin glass sheet is not limited to that described here, but may include any thickness below the minimum thickness requirement of the LCD equipment that may be suitable for touch sensor panels. 
       FIG. 4  illustrates an exemplary method for fabricating a thin glass sheet according to embodiments of the invention. Optionally using standard LCD technology, a standard LCD thin film deposition tool may be used to place a thin film pattern on a surface of a thick glass sheet ( 405 ). The thick glass sheet may have a thickness of 0.5 mm or more to meet the minimum thickness requirement of standard LCD equipment. A standard LCD material deposition tool may be used to apply a protective layer overlaying the patterns on a surface of the thick glass sheet ( 410 ). The combined sheet and layer may have a thickness of more than 0.5 mm, which also meets the minimum thickness requirement of standard LCD equipment. A standard LCD thinning tool may be used to thin the surface of the glass sheet opposite the surface having the protective layer, where the thicknesses of the glass sheet may be thinned to less than 0.5 mm ( 415 ). Optionally, the protective layer may also be thinned. The combination of the thinned sheet and layer may maintain a thickness of 0.5 mm or more, which still meets the minimum thickness requirement of standard LCD equipment. The standard LCD thin film deposition tool may be used again to coat the thinned outside surface of the sheet ( 420 ) to complete the standard LCD fabrication process. 
     After completing the standard LCD fabrication process, the protective layer may be removed from the surface of the glass sheet. Any suitable removal tool known to those skilled in the art may be used to do so, leaving the thin glass sheet remaining ( 425 ). The resulting thin glass sheet may have a thickness of less than 0.5 mm, which is below the minimum thickness requirement of standard LCD equipment, yet still advantageously have been fabricated using that equipment. 
       FIG. 5   a  illustrates exemplary digital media player  510  that can include touch sensor panel  515 , the touch sensor panel including a thin glass sheet having a thickness of less than 0.5 mm according to embodiments of the invention. 
       FIG. 5   b  illustrates exemplary mobile telephone  520  that can include touch sensor panel  525 , the touch sensor panel including a thin glass sheet having a thickness of less than 0.5 mm according to embodiments of the invention. 
     The media player and the mobile telephone of  FIGS. 5   a  and  5   b  can achieve lighter weights utilizing thin glass sheets according to embodiments of the invention. 
       FIG. 6  illustrates exemplary computing system  600  that can include one or more of the embodiments of the invention described above. Computing system  600  can include one or more panel processors  602  and peripherals  604 , and panel subsystem  606 . Peripherals  604  can include, but are not limited to, random access memory (RAM) or other types of memory or storage, watchdog timers and the like. Panel subsystem  606  can include, but is not limited to, one or more sense channels  608 , channel scan logic  610  and driver logic  614 . Channel scan logic  610  can access RAM  612 , autonomously read data from the sense channels and provide control for the sense channels. In addition, channel scan logic  610  can control driver logic  614  to generate stimulation signals  616  at various frequencies and phases that can be selectively applied to drive lines of touch sensor panel  624 . In some embodiments, panel subsystem  606 , panel processor  602  and peripherals  604  can be integrated into a single application specific integrated circuit (ASIC). 
     Touch sensor panel  624  can include a capacitive sensing medium having a plurality of drive lines and a plurality of sense lines, although other sensing media can also be used. Either or both of the drive and sense lines can be coupled to a thin glass sheet according to embodiments of the invention. Each intersection of drive and sense lines can represent a capacitive sensing node and can be viewed as picture element (pixel)  626 , which can be particularly useful when touch sensor panel  624  is viewed as capturing an “image” of touch. (In other words, after panel subsystem  606  has determined whether a touch event has been detected at each touch sensor in the touch sensor panel, the pattern of touch sensors in the multi-touch panel at which a touch event occurred can be viewed as an “image” of touch (e.g. a pattern of fingers touching the panel).) Each sense line of touch sensor panel  624  can drive sense channel  608  (also referred to herein as an event detection and demodulation circuit) in panel subsystem  606 . 
     Computing system  600  can also include host processor  628  for receiving outputs from panel processor  602  and performing actions based on the outputs that can include, but are not limited to, moving an object such as a cursor or pointer, scrolling or panning, adjusting control settings, opening a file or document, viewing a menu, making a selection, executing instructions, operating a peripheral device coupled to the host device, answering a telephone call, placing a telephone call, terminating a telephone call, changing the volume or audio settings, storing information related to telephone communications such as addresses, frequently dialed numbers, received calls, missed calls, logging onto a computer or a computer network, permitting authorized individuals access to restricted areas of the computer or computer network, loading a user profile associated with a user&#39;s preferred arrangement of the computer desktop, permitting access to web content, launching a particular program, encrypting or decoding a message, and/or the like. Host processor  628  can also perform additional functions that may not be related to panel processing, and can be coupled to program storage  632  and display device  630  such as an LCD panel for providing a UI to a user of the device. Display device  630  together with touch sensor panel  624 , when located partially or entirely under the touch sensor panel, can form touch screen  618 . 
     Note that one or more of the functions described above can be performed by firmware stored in memory (e.g. one of the peripherals  604  in  FIG. 6 ) and executed by panel processor  602 , or stored in program storage  632  and executed by host processor  628 . The firmware can also be stored and/or transported within any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. In the context of this document, a “computer-readable medium” can be any medium that can contain or store the program for use by or in connection with the instruction execution system, apparatus, or device. The computer readable medium can include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus or device, a portable computer diskette (magnetic), a random access memory (RAM) (magnetic), a read-only memory (ROM) (magnetic), an erasable programmable read-only memory (EPROM) (magnetic), a portable optical disc such a CD, CD-R, CD-RW, DVD, DVD-R, or DVD-RW, or flash memory such as compact flash cards, secured digital cards, USB memory devices, memory sticks, and the like. 
     The firmware can also be propagated within any transport medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. In the context of this document, a “transport medium” can be any medium that can communicate, propagate or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The transport readable medium can include, but is not limited to, an electronic, magnetic, optical, electromagnetic or infrared wired or wireless propagation medium. 
     Although the invention has been fully described in connection with embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications will become apparent to those skilled in the art. Such changes and modifications are to be understood as being included within the scope of the invention as defined by the appended claims.

Metadata:
Filing Date: 20080627
Publication Date: 20140318
Grant Date: 20140318
Priority Date: 20080627
Inventors: ZHONG JOHN Z.
FEINSTEIN CASEY J.
HOTELLING STEVE PORTER
CHANG SHIH CHANG
Assignee: APPLE INC
CPC Classifications: [{"code": "C03C15/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "C03C15/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "B24B7/242", "inventive": true, "first": true, "tree": "[]"}, {"code": "H05K1/0274", "inventive": true, "first": true, "tree": "[]"}, {"code": "Y10T428/266", "inventive": false, "first": false, "tree": "[]"}, {"code": "B24B7/242", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y10T428/24926", "inventive": false, "first": false, "tree": "[]"}, {"code": "B24B7/242", "inventive": true, "first": true, "tree": "[]"}, {"code": "B24B7/241", "inventive": true, "first": false, "tree": "[]"}, {"code": "B24B7/241", "inventive": true, "first": false, "tree": "[]"}, {"code": "C03C15/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y10T428/266", "inventive": false, "first": false, "tree": "[]"}, {"code": "C03C19/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y10T428/24926", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 41447824