Mobile phone

A mobile phone includes a body defining a display panel, and a touch panel. The body further includes a communicating system received therein. The touch panel is disposed on a surface of the display panel. The touch panel includes at least a carbon nanotube layer. The carbon nanotube layer includes a carbon nanotube film.

RELATED APPLICATIONS

BACKGROUND

1. Technical Field

The present disclosure relates to mobile phones, and, in particular, to a mobile phone employed with a touch panel based on carbon nanotubes.

2. Description of the Related Art

Conventionally, mobile phones include a body, a display panel disposed on a surface of the body, and an input device, such as a keyboard mounted on the surface of the body. Following the development of various electronic apparatuses in recent years, a touch panel has been widely applied to the display panel of the mobile phones.

At present, different types of touch panels have been developed, including a resistance-type, a capacitance-type, an infrared-type, and a surface sound wave-type. The resistance-type and capacitance-type touch panels have been widely used in mobile phones because of higher accuracy and resolution.

A typical capacitance-type touch panel includes a glass substrate, a transparent conductive layer, and four electrodes. It is well known that a layer of an indium tin oxide (ITO) is adopted to function as the transparent conductive layer. However, the ITO layer of the touch panel has poor mechanical durability, low chemical endurance, and uneven resistance over the entire area of the touch panel. Furthermore, the ITO layer has relatively low transparency in humid environments. All the above-mentioned problems of the ITO layer tend to yield a touch panel with relatively low sensitivity, accuracy, and brightness. Moreover, the ITO layer is generally formed by means of ion-beam sputtering, a relatively complicated method.

What is needed, therefore, is a mobile phone having an improved touch panel that can overcome the above-described shortcomings.

DETAILED DESCRIPTION

Referring toFIGS. 1 and 2, first embodiment of a mobile phone100includes a body102and a touch panel10. The body102defines a display panel104. The touch panel10is disposed on the display panel104.

The body102may further include a housing190, a communicating system, a central processing unit (CPU)160, a controlling unit150, and a memory unit170. The communicating system includes an antenna192, a microphone194, and a speaker196. The CPU160, the controlling unit150, the memory unit170, the microphone194, the speaker196, and the display panel104are received in the housing190. The antenna192may be received in the housing190or extend out of the surface of the housing190. The CPU160, the controlling unit150, and the memory unit170may be mounted on an integrated circuit board. The memory unit170and the controlling unit150are electrically connected to the CPU160via wires of the integrated circuit board. The speaker196, the microphone194, the antenna192, the display panel104, and the touch panel10are electrically connected to the controlling unit150. The controlling unit150includes a touch-panel controller, a display controller, and a communicating controller. These controllers are used for controlling the touch panel10, the display panel104, the speaker196, the microphone194, and the antenna192. The memory unit170includes a random access memory and a read only memory and is configured to store instructions that can be dealt with and executed by the CPU160, and signals which are displayed via the display panel104. The antenna192receives and sends radio frequency signals. The radio frequency signals are transported to a processor and transformed into audio signals. Accordingly, the speaker196works under the control of the controlling unit150. The microphone194receives sounds and transforms the sounds into audio signals. Then, the audio signals are transported to the CPU160and transformed into radio frequency signals and sent out via the antenna192under the control of the controlling unit150.

The display panel104may be a liquid crystal display panel, a field emission display panel, a plasma display panel, an electroluminescent display panel, or a vacuum fluorescent display panel. The display panel104is used for displaying dates or views from the body102. In the present embodiment, the display panel104is a liquid crystal display panel.

The touch panel10may be spaced apart from the display panel104or integrated with the display panel104. When the touch panel10is integrated with the display panel104, it may be directly adhered onto a surface of the display panel104via paste or share a common substrate with the display panel104(that is to say, the second substrate140of the touch panel10functions as an emission plate of the display panel104). Users can input instructions for the body102via touching or pressing the touch panel10by using an input device, such as keyboard, pen, or finger.

Referring toFIG. 3andFIG. 4, the touch panel10is a resistive touch panel and includes a first electrode plate12, a second electrode plate14, and a plurality of transparent dot spacers16. The second electrode plate14is directly adhered to the display panel104.

The first electrode plate12includes a first substrate120, a first conductive layer122, and two first electrodes124. The first substrate120has a planar structure, and includes a first surface. The first conductive layer122and the two first electrodes124are mounted on the first surface of the first substrate120. The two first electrodes124are respectively disposed on the two ends of the first substrate120along a first direction and electrically connected to the first conductive layer122. In the present embodiment, the first direction is marked as the X-direction. The second electrode plate14includes a second substrate140, a second conductive layer142and two electrodes144. The second substrate140has a planar structure, and includes a second surface. The second surface of the second substrate140is faced to the first surface of the first substrate120. The second conductive layer142and the two electrodes144are disposed on the second surface of the second substrate140. The two electrodes144are respectively disposed on the two ends of the second ends of the second substrate140along a second direction and electrically connected to the second conductive layer142. The second direction is marked as the Y direction. The X direction is substantially perpendicular to the Y direction, namely, the two first electrodes124are substantially orthogonal to the two second electrodes144.

The first substrate120can be a transparent and flexible film or plate made of polymer, resin, or any other suitable flexible material. The second substrate140can be a rigid and transparent board made of glass, diamond, quartz, plastic or any other suitable material, or can be a transparent flexible film or plate similar to the first substrate120, if the touch panel10is flexible. A material of the flexible film or plate can be one or more of polycarbonate (PC), polymethyl methacrylate acrylic (PMMA), polyethylene terephthalate (PET), polyether polysulfones (PES), polyvinyl polychloride (PVC), benzocyclobutenes (BCB), polyesters, and acrylic resins. The thickness of the first substrate120and the second substrate140can be in the range from about 5 millimeters to about 1 centimeter.

Furthermore, an insulating pad18is disposed on the periphery of the second surface of the second electrode plate14. The first electrode plate12is disposed on the insulating pad18. The first conductive layer122of the first electrode plate12is faced to the second conductive layer142of the second electrode plate14. The plurality of transparent dot spacer16are spaced apart from one another and disposed on the second conductive layer142of the second electrode plate14. A distance between the first and second electrode plates12,14is in a range of about 2 mm to about 100 mm. The insulating pad18and the dot spacers16are made of transparent resin or the like and are used for insulating the first electrode plate12with the second electrode plate14. Understandably, if the resistive touch panel10is small enough, the dot spacers16may be omitted.

A transparent protective film126may be disposed on the top surface of the first electrode plate12. The transparent protective film126may be directly adhered on the first electrode plate12via paste, or combined with the first electrode plate12via a heat-press method. The transparent protective film126may be a plastic layer or a resin layer, which are treated via surface rigid treating. The resin layer may be made of benzo cyclo butene, polymethyl methacrylate, polymer resin, polyethylene terephthalate, or the like. In the present embodiment, the transparent protective film126is made of polyethylene terephthalate, and configured for protecting the first electrode plate12by improving wearability thereof. The transparent protective film126may provide some additional function, such as decreasing glare and reflection.

At least one of the first and second conductive layers122,142includes a carbon nanotube layer. The carbon nanotube layer includes one or more carbon nanotube films. The carbon nanotube film is formed by a plurality of carbon nanotubes, ordered or otherwise, and has a uniform thickness. The carbon nanotube film can be an ordered film or a disordered film. The ordered carbon nanotube film consists of ordered carbon nanotubes. Ordered carbon nanotube films include films where the carbon nanotubes are arranged along a primary direction. Examples include films where the carbon nanotubes are arranged approximately along a same direction or have two or more sections within each of which the carbon nanotubes are arranged approximately along a same direction (different sections can have different directions). In the ordered carbon nanotube film, the carbon nanotubes can be primarily oriented along a same direction. However, the ordered carbon nanotube film can also have sections of carbon nanotubes aligned in a common direction. The ordered carbon nanotube film can have two or more sections, and the sections can have different alignments. The ordered carbon nanotube film may have a free-standing structure. The free-standing carbon nanotube film may include two types. One type is that the carbon nanotube film needs no substrate to support the carbon nanotubes thereof. Another type is that the carbon nanotube film only needs one or more supporting dots (not shown) to support one or more points thereof. Thus, left parts of the carbon nanotube film are hung. In the ordered carbon nanotube films, the carbon nanotubes are oriented along a same preferred orientation and approximately parallel to each other. The term “approximately” as used herein means that it is impossible and unnecessary that each of carbon nanotubes in the carbon nanotube films be exactly parallel to one another, namely that every carbon nanotubes is parallel to each other, because in the course of fabricating the carbon nanotube film, some factor, such as the change of drawing speed, affects the non-uniform drawing force on the carbon nanotube film as the carbon nanotube film is drawn from a carbon nanotube array. A film can be drawn from a carbon nanotube array, to form the ordered carbon nanotube film, namely a drawn carbon nanotube film. Examples of drawn carbon nanotube film are taught by US 20080170982 to Zhang et al. The drawn carbon nanotube film includes a plurality of successive and oriented carbon nanotubes joined end-to-end by van der Waals attractive force therebetween. The drawn carbon nanotube film is a free-standing film. The carbon nanotube film can be treated with an organic solvent to increase the mechanical strength and toughness of the carbon nanotube film and reduce the coefficient of friction of the carbon nanotube film. A thickness of the carbon nanotube film can range from about 0.5 nanometers to about 100 micrometers.

The disordered carbon nanotube film consists of disordered carbon nanotubes. Disordered carbon nanotube films include randomly aligned carbon nanotubes. When the disordered carbon nanotube film has a number of the carbon nanotubes aligned in every direction that are substantially equal, the disordered carbon nanotube film can be isotropic. The disordered carbon nanotubes can be entangled with each other and/or are approximately parallel to a surface of the disordered carbon nanotube film. The disordered carbon nanotube film may be a flocculated carbon nanotube film. The flocculated carbon nanotube film can include a plurality of long, curved, disordered carbon nanotubes entangled with each other. Furthermore, the carbon nanotubes in the flocculated carbon nanotube film can be isotropic. The carbon nanotubes can be substantially uniformly dispersed in the carbon nanotube film. Adjacent carbon nanotubes are attracted by van der Waals attractive force to form an entangled structure with micropores defined therein. It is understood that the flocculated carbon nanotube film is very porous. Sizes of the micropores can be less than 10 micrometers. The porous nature of the flocculated carbon nanotube film will increase specific surface area of the carbon nanotube structure. Furthermore, due to the carbon nanotubes in the flocculated carbon nanotube film being entangled with each other, the touch panel10employing the flocculated carbon nanotube film has excellent durability, and can be fashioned into desired shapes with a low risk to the integrity of the flocculated carbon nanotube film. The thickness of the flocculated carbon nanotube film can range from about 0.5 nanometers to about 1 millimeter.

The pressed carbon nanotube film can be a free-standing carbon nanotube film. The carbon nanotubes in the pressed carbon nanotube film may be arranged along a same direction or arranged along different directions. When the carbon nanotubes in the pressed carbon nanotube film are arranged along a same direction, the pressed carbon nanotube film is a ordered carbon nanotube film. When the carbon nanotubes in the pressed carbon nanotube film are arranged along different directions, the pressed carbon nanotube film is a disordered carbon nanotube film. The carbon nanotubes in the pressed carbon nanotube film can rest upon each other. Adjacent carbon nanotubes are attracted to each other and combined by van der Waals attractive force. An angle between a primary alignment direction of the carbon nanotubes and a surface of the pressed carbon nanotube film is approximately 0 degrees to approximately 15 degrees. The greater the pressure applied, the smaller the angle formed. When the carbon nanotubes in the pressed carbon nanotube film are arranged along different directions, the pressed carbon nanotube film can be isotropic. The thickness of the pressed carbon nanotube film ranges from about 0.5 nm to about 1 mm. Examples of pressed carbon nanotube film are taught by US application 20080299031A1 to Liu et al.

A length and a width of the carbon nanotube film can be arbitrarily set as desired. A thickness of the carbon nanotube film is in a range from about 0.5 nanometers to about 100 micrometers. The carbon nanotubes in the carbon nanotube film can be selected from the group consisting of single-walled, double-walled, multi-walled carbon nanotubes, and combinations thereof. Diameters of the single-walled carbon nanotubes, the double-walled carbon nanotubes, and the multi-walled carbon nanotubes can, respectively, be in the approximate range from about 0.5 nanometers to about 50 nanometers, about 1 nanometer to about 50 nanometers, and about 1.5 nanometers to about 50 nanometers.

Referring toFIG. 5, in the present embodiment, the first conductive layer122and the second conductive layer124each include a carbon nanotube layer. The carbon nanotube layer is an ordered carbon nanotube film. The carbon nanotube layer may include a number of carbon nanotube films stacked with each other. The carbon nanotubes of each of the carbon nanotube films are arranged alone a preferred orientation. The carbon nanotube film includes a number of carbon nanotube segments joined end by end via van der Waals attractive forces. The carbon nanotube segments have a substantially same length and composed of a number of approximately parallel arranged carbon nanotubes. In the present embodiment, the carbon nanotube films of the first conductive layer122are overlapped alone the first direction, and the carbon nanotube films of the second conductive layer124are overlapped along the second direction. The carbon nanotube films have thickness of about 0.5 nm to 100 mm and width of 0.01 cm to about 10 cm.

The mobile phone100may further include a shielding layer19disposed on the bottom surface of the touch panel10. The material of the shielding layer19can be a conductive resin film, a carbon nanotube film, or another kind of flexible and conductive film. In the present embodiment, the shielding layer19is a carbon nanotube film. The carbon nanotube film includes a plurality of carbon nanotubes, and the orientation of the carbon nanotubes therein can be arbitrarily determined. Understandably, the carbon nanotubes in the carbon nanotube film of the shielding layer19can be arranged along a same direction. The carbon nanotube film is connected to ground and acts as shielding, thus enabling the touch panel10to operate without interference (e.g., electromagnetic interference).

The mobile phone100may further include a passivation layer13interposed between the display panel104and the touch panel10. The passivation layer13is used for preventing crosstalk, electrochemical corrosion, and so on, or reducing power consumption. The passivation layer13may be made of silicon nitrogen, silicon oxide, or the like.

Referring toFIG. 6, in operation, a voltage of about 5 volts, for example, is applied to the first and second electrodes124,144. Equipotential lines parallel to the first and second electrodes are formed in the first and second transparent conductive layers122,142. A user operates the mobile phone100by pressing or touching the touch panel10with a touch tool180, such as a finger, or a pen/stylus, while visually observing the display panel104through the touch panel10. An input position182can be determined from X-Y coordinates based on the X Y directions and corresponding to the potential of the input position182developed from the press or touch of the touch panel10. With the first and second conductive layers122,142set so that the equipotential lines intersect at right angles, and alternatively switching transistors with a period of several milliseconds, the coordinates of the input position182are detected. The controlling unit150detects coordinates of the touch point on the touch panel10according to change of currents of the first and second electrodes124,144. Then the touch panel10sends the coordinates of the touch point to the CPU160. The CPU160reads an instruction, according to the coordinates of the touch point, in the memory unit170, and sends the instruction to the controlling unit150. The controlling unit150controls the display panel104, the antenna192, the microphone194, and the speaker196to operate according to the instruction.

Referring toFIG. 7andFIG. 9, a second embodiment of a mobile phone200includes a body (not shown) and a touch panel20. The body defines a display panel204thereon. The touch panel20is disposed on the touch panel far away from the body.

The touch panel20is a capacitive touch panel. The touch panel20includes a substrate22, a transparent conductive layer24, at least two electrodes28, and a transparent protective film26. The substrate22is adjacent to the display panel204. It is appreciated that the substrate22may function as the top substrate of the display panel204, namely, the touch panel20shares a common substrate with the display panel204. The substrate22includes a first surface221and a second surface222opposite to the first surface221. The first surface221is far away from the display panel204. The transparent conductive layer24is mounted on the first surface221of the substrate22. At least two electrodes28are disposed at the periphery of the transparent conductive layer24, spaced from each other, and electrically connected to the transparent conductive layer24to form equipotential lines thereon. The transparent protective layer26can be directly disposed on the transparent conductive layer24and the electrodes28.

In the present embodiment, the touch panel20has four electrodes28respectively disposed on the four sides of the transparent conductive layer24. Understandably, the four electrodes28can be disposed on the different surfaces of the transparent conductive layer24as long as equipotential lines can be formed on the transparent conductive layer24.

Understandably, the four electrodes28can be disposed between the transparent conductive layer24and the substrate22and electrically connected to the transparent conductive layer24.

The substrate22has a curved structure or a planar structure and functions as a supporter for the touch panel20. The supporter is sandwiched between the touch panel20and the display panel204. The substrate22is made of a rigid material or a flexible material, such as glass, silicon, diamond, plastic, or the like.

The transparent conductive layer24includes a carbon nanotube layer. The carbon nanotube layer includes a number of uniformly arranged carbon nanotubes, and the carbon nanotubes are orderly, or disorderly arranged. In the present embodiment, the carbon nanotube layer of the transparent conductive layer24has the same configuration as the first and second conductive layer122,124of the first embodiment of the mobile phone100.

The four electrodes28are made of metal, a carbon nanotube thin film, or the like. In the present embodiment, the four electrodes28are layers of silver, copper, or foils of metal and have strip-shaped structures.

In order to prolong the life of the transparent conductive layer24and limit capacitance between the touch point and the transparent conductive layer24, a transparent protective film26is disposed on the transparent conductive layer24and the electrodes28. The transparent protective film26is made of polyethylene terephthalate, silicon nitrogen, silicon oxide or the like, and configured for protecting the transparent conductive layer24by improving wearability thereof. The transparent protective film26may provide some additional function, such as decreasing glare and reflection after special treating.

In the present embodiment, the transparent protective film26, which is made of silicon dioxide, is disposed on the transparent conductive layer24on which the electrodes28is mounted. The transparent protective film26has a hardness of 7H (H established according to Rockwell hardness test). Understandably, the hardness and the thickness of the transparent protective film26may be varied in practice as desired. The transparent protective film26is directly adhered on the transparent conductive layer24via paste.

The mobile phone200further includes a shielding layer23disposed on the second surface222of the touch panel10when the touch panel20is integrated with the display panel204. The material of the shielding layer23can be a conductive resin film, indium tin oxide, antimony doped tin oxide, a carbon nanotube film, or another kind of flexible and conductive film. In the present embodiment, the shielding layer23is a carbon nanotube film. The carbon nanotube film includes a plurality of carbon nanotubes, and the orientation of the carbon nanotubes therein can be arbitrarily determined. Understandably, the carbon nanotubes in the carbon nanotube film of the shielding layer can be arranged along a same direction. The carbon nanotube film is connected to ground and acts as shielding, thus enabling the touch panel20to operate without interference (e.g., electromagnetic interference).

The mobile phone200further include a passivation layer25interposed between the display panel204and the touch panel20. The passivation layer25is used for preventing crosstalk, electrochemical corrosion, and so on, or reducing power consumption. The passivation layer25may be made of silicon nitrogen, silicon oxide, or the like.

In use, when a user operates the mobile phone200by pressing or touching the touch panel20with a touch tool (not shown), such as a finger, or a pen/stylus, the capacitance at the touch point changes, which results in a change in frequency of an oscillator (not shown). By alternatively switching the oscillator within a period of several milliseconds, the coordinates of the input point are detected. The controlling unit250calculates the proportion of the four supplied currents of the four transparent electrodes28, thereby detecting coordinates of the touch point on the touch panel20. Then the controlling unit250sends the coordinates of the touch point to the CPU260. The CPU260reads an instruction according to the coordinates of the touch point in the memory unit270and sends the instruction to the controlling unit250. The controlling unit250controls the display panel204, the antenna, the microphone, and the speaker to operate according to the instruction.

As described above, the carbon nanotube films employed in the touch panel has superior properties, such as excellent toughness, high mechanical strength, and uniform conductivity. Thus, the touch panel and the mobile phone using the same are durable and highly conductive. Each of the carbon nanotube films includes a number of successively oriented carbon nanotubes joined end to end by the van der Waals attractive force therebetween. As such, the carbon nanotube films are flexible, and suitable for using as the conductive layer in a flexible touch panel. Furthermore, the carbon nanotube films have high transparency, thereby promoting improved brightness of the touch panel and the mobile phone using the same. Additionally, since the carbon nanotubes have excellent electrical conductivity properties, the carbon nanotube films have a uniform resistance distribution. Thus, the touch panel and the mobile phone adopting the carbon nanotube films have improved sensitivity and accuracy.