Panel unit capable of avoiding contact between electrically conductive bodies thereon

A first electrically conductive stripe extends from a starting point to an end point on the front surface of a lower base member in a panel unit. An upper base member is designed to oppose its back surface to the front surface of the lower base member. A second electrically conductive stripe extends on the back surface of the upper base member from a corresponding starting point opposed to the starting point to a corresponding end point opposed to the end point. The second electrically conductive stripe intersects across the first electrically conductive stripe two or more times. When an urging force is applied on the upper base member, the second electrically conductive body is urged toward the first electrically conductive body. Contact is surely prevented between the first and second electrically conductive stripes. The panel unit is thus allowed to normally keep operating.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a panel unit such as a touch screen panel unit, for example.

2. Description of the Prior Art

A so-called analog resistive touch screen panel unit includes a glass substrate and a resin film opposing the back surface to the front surface of the glass substrate. Indium-tin oxide (ITO) films are formed to spread over the front surface of the glass substrate and the back surface of the resin film, respectively. Electrically conductive lines extend adjacent the peripheries of the ITO films along the peripheries of the glass substrate and resin film, respectively. The electrically conductive lines are in this manner opposed to each other. An adhesive layer is interposed between the electrically conductive lines on the glass substrate and resin film so as to adhere the resin film to the glass substrate. The electrically conductive lines and the adhesive layer are located off an window opening defined in an enclosure of a display apparatus, for example.

A user of a notebook personal computer often grasps the enclosure at a position off the window opening. The resin film is forced to receive an urging force from the enclosure. The adhesive layer is squashed between the electrically conductive lines. Since the electrically conductive lines are constantly opposed to each other, the electrically conductive lines tends to contact with each other. If the electrically conductive lines contact each other, the touch screen panel unit cannot normally operate.

One of the electrically conductive lines may be entirely displaced off the other of the electrically conductive lines so as to avoid the aforementioned contact of the electrically conductive lines. In this case, the adhesive layer slides off from a predetermined position when the resin film receives an urging force. In addition, a larger area is required around the window opening to locate the electrically conductive lines. This contradicts a recent trend of reducing an area around the window opening.

SUMMARY OF THE INVENTION

It is accordingly an object of the present invention to provide a panel unit capable of avoiding contact between electrically conductive bodies to the utmost.

According to a first aspect of the present invention, there is provided a panel unit comprising: a lower base member; a stripe of a first electrically conductive body extending from a starting point to an end point on the front surface of the lower base member; an upper base member opposing its back surface to the front surface of the lower base member; and a stripe of a second electrically conductive body extending on the back surface of the upper base member from a corresponding starting point opposed to the starting point to a corresponding end point opposed to the end point, said second electrically conductive body intersecting across the first electrically conductive body two or more times.

When an urging force is applied on the upper base member in the panel unit, the second electrically conductive body is urged toward the first electrically conductive body. Since the second electrically conductive body intersects across the first electrically conductive body two or more times, the lap can to the utmost be reduced between the first and second electrically conductive bodies. Contact is surely prevented between the first and second electrically conductive bodies. The panel unit is thus allowed to normally keep operating. In this case, the first electrically conductive body may serpentine on the front surface of the lower base member. Likewise, the second electrically conductive body serpentines on the back surface of the upper base member. The lower and upper base members may have permeability of light.

The panel unit may further include: a frame member received on the front surface of the upper base member, said frame member defining a window opening along the front surface of the upper base member; and an insulator layer interposed between the first and second electrically conductive bodies, said insulator layer receiving an urging force acting on the upper base member from the frame member. Here, the first electrically conductive body may extend along the periphery of the lower base member.

The user often grasps the periphery of the panel unit. A larger urging force is applied to the upper base member from the frame member. The urging force causes the second electrically conductive body to be urged toward the first electrically conductive body. In this case, the second electrically conductive body intersects across the first electrically conductive body two or more times, so that the lap is to the utmost reduced between the first and second electrically conductive bodies. Contact is surely prevented between the first and second electrically conductive bodies. The panel unit thus keeps normally operating.

In addition, when the urging force is received on the upper base member from the frame member, the second electrically conductive body is urged toward the first electrically conductive body. Since the second electrically conductive body intersects across the first electrically conductive body two or more times, a lateral shift can be prevented between the first and second electrically conductive bodies along the surfaces of the upper and lower base members. The panel unit may be assembled into a display apparatus, an electronic apparatus, or the like. The display apparatus, the electronic apparatus, or the like may further include a display panel unit, in addition to the panel unit of the first aspect. In this case, the lower base member may be located along the front surface of the display panel unit.

According to a second aspect of the present invention, there is provided a first base member; an electrically conductive film extending on the front surface of the first base member between a pair of electrode; an electrically conductive line connected to at least one of the electrodes, said electrically conductive line extending from a starting point to an end point on the front surface of the first base member at a location spaced from the electrically conductive film; a second base member opposing the back surface to the front surface of the first base member; and a stripe of an electrically conductive body extending on the back surface of the second base member from a corresponding starting point opposed to the starting point to a corresponding end point opposed to the end point, said electrically conductive body intersecting across the electrically conductive line two or more times.

When an urging force is applied on the second base member in the panel unit, the electrically conductive body is urged toward the electrically conductive line. Since the electrically conductive body intersects across the electrically conductive line two or more times, the lap can to the utmost be reduced between the electrically conductive body and the electrically conductive line. Contact is surely prevented between the electrically conductive body and the electrically conductive line. The panel unit is thus allowed to normally keep operating. In this case, the electrically conductive body may be an electrode connected to an electrically conductive film extending on the back surface of the second base member at a position opposed to the electrically conductive film on the first base member. The first and second base members may have permeability of light.

The panel unit may further include: a frame member received on the front surface of the second base member, said frame member defining a window opening along the front surface of the second base member; and an insulator layer interposed between the electrically conductive body and the electrically conductive line, said insulator layer receiving an urging force acting on the second base member from the frame member. Here, the electrically conductive body may extend along the periphery of the second base member.

The user often grasps the periphery of the panel unit. A larger urging force is applied to the second base member from the frame member. The urging force causes the electrically conductive body to be urged toward the electrically conductive line. In this case, the electrically conductive body intersects across the electrically conductive line two or more times, so that the lap is to the utmost reduced between the electrically conductive body and the electrically conductive line. Contact is surely prevented between the electrically conductive body and the electrically conductive line. The panel unit thus keeps normally operating.

In addition, when the urging force is received on the second base member from the frame member, the electrically conductive body is urged toward the electrically conductive line. Since the electrically conductive body intersects across the electrically conductive line two or more times, a lateral shift can be prevented between the electrically conductive body and the electrically conductive line along the surfaces of the first and second base members. The panel unit maybe assembled into a display apparatus, an electronic apparatus, or the like. The display apparatus, the electronic apparatus, or the like may further include a display panel unit, in addition to the panel unit of the second aspect. In this case, the first base member may be located along the front surface of the display panel unit.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1schematically illustrates a notebook personal computer11as a specific example of an electronic apparatus. The notebook personal computer11includes a thin equipment body12and a display apparatus14coupled to the equipment body12for a relative swinging movement around a predetermined rotation axis13.

A motherboard, not shown, is contained within the enclosure of the equipment body12. As conventionally known, a processing circuits such as a central processing unit (CPU) and a memory, for example, are mounted on the motherboard. The CPU serves to operate based on an operating system (OS) and application softwares temporality stored in the memory. The user is allowed to input various data and instructions to the CPU through input devices such as a keyboard15, a pointing device16, and the like.

The display apparatus14includes a display enclosure17. A rectangular window opening18is defined in the display enclosure17. The window opening18serves to expose the screen of a liquid crystal display (LCD) panel. Graphics and texts can be displayed on the screen of the LCD panel based on the operation of the CPU.

As shown inFIG. 2, the display enclosure17includes a base19and a cover21coupled to the base19. The cover21serves as a frame member. The cover21and the base19may be made from resin material such as polycarbonate, metal material such as magnesium, or the like. Molding process may be employed to form the cover21and the base19. A touch screen panel unit22is contained within a space defined between the cover21and the base19. The space between the cover21and the base19also contains a LCD panel unit23superposed on the back surface of the touch screen panel unit22. The touch screen panel unit22have at least permeability of light or transparency.

Screws24are screwed into the display enclosure17so as to couple the cover21with the base19. The axes of the screws24are aligned in the direction perpendicular to the screen of the display apparatus14. The screws24are inserted from the front surface of the cover21. Penetrating holes25are defined in the cover21so as to receive the insertion of the respective screws24. The penetrating holes25may be covered with a dressed material, not shown, for example.

The touch screen panel unit22includes a flexible printed circuit (FPC) board26extending toward the equipment body12. The flexible printed circuit board26is connected to the motherboard within the equipment body12. A controller circuit such as a controller chip, not shown, is mounted on the motherboard. The controller circuit serves to control the operation of the touch screen panel unit22.

Panel-shaped module components such as a LCD panel, a diffuser, a prism plate, a light guide plate, a reflector are in this sequence superposed on one another in the LCD panel unit23. Two fluorescent tubes are disposed adjacent the lower end of the light guide plate, for example. A circuit board is disposed behind the reflector for controlling the display. The circuit board is interposed between front and back insulating sheets. A flexible printed circuit board is connected to the circuit board. The flexible printed circuit board is connected to the motherboard within the equipment body12.

A spacer27is interposed between the touch screen panel unit22and the LCD panel unit23. The spacer27includes a surrounding that surrounds the outer periphery of the touch screen panel unit22. The back surface of the spacer27is received on the front surface of the LCD panel unit23. The spacer27may be made of any elastic material such as rubber. The spacer27serves to keep a predetermined space between the touch screen panel unit22and the LCD panel unit23.

Protruding tongues28are defined in the LCD panel unit23. The protruding tongues28are designed to extend outward from the outer periphery of the LCD panel unit23. Penetrating holes29are defined in the protruding tongues28to receive the insertion of the screws24. On the other hand, screwed bores31are formed in the base19so as to receive the insertion of the screws24. The screws24are received in the screwed bores31after the screws24have penetrating through the cover21and the protruding tongue28. The touch screen panel unit22and the LCD panel unit23are in this manner fixed between the cover21and the base19.

As shown inFIG. 3, the touch screen panel unit22includes a rectangular first base member or lower base member35, and a rectangular second base member or upper base member36opposing the back surface to the front surface of the lower base member35. The lower base member35may be made of a transparent glass substrate, for example. The lower base member35thus has permeability of light. The upper base member36may be made of a transparent resin film such as polyethylene terephthalate (PET) film, for example. The upper base member36thus has permeability of light. The upper base member36has a contour identical to that of the lower base substrate35. An adhesive material37is interposed between the lower and upper base members35,36. The adhesive material37forms a frame extending along the outer periphery of the lower and upper base members35,36. The adhesive material37serves to fixedly couple the periphery of the upper base member36with the periphery of the lower base member35.

Referring also toFIG. 4, a transparent first electrically conductive film38extends over the front surface of the lower base member35. The first electrically conductive film38has a rectangular shape. The front surface of the lower base member35is exposed around the first electrically conductive film38. The first electrically conductive film38may be made of an indium-tin oxide (ITO) film, for example. Dot spacers39are located on the upper surface of the first electrically conductive film38at positions equally spaced. The dot spacers39are arranged according to a lattice. The dot spacer39is a hemisphere swelling from the upper surface of the first electrically conductive film38. The dot spacers39may be made of a resin material having an insulating property, for example.

A first electrically conductive body41extends on the front surface of the lower base member35along the outer periphery of the lower base member35. The first electrically conductive body41includes a pair of first electrode42a,42band a pair of first electrically conductive line43a,43b.The first electrodes42a,42bare individually connected to the first electrically conductive film38. The first electrically conductive lines43a,43bare separately connected to the first electrodes42a,42b,respectively. The first electrodes42a,42bextend along the longer sides of the rectangular first electrically conductive film38. The first electrically conductive film38thus extends between the first electrodes42a,42b.The first electrically conductive line43aextends toward the flexible printed circuit board26at a location spaced from the first electrically conductive film38. The first electrically conductive line43afirst extends along the shorter side of the rectangular first electrically conductive film38. The first electrically conductive line43athen extends in parallel with the first electrode42b.The first electrically conductive line43aserpentines along a straight line connecting a starting point44and an end point45. The first electrically conductive line43blikewise extends toward the flexible printed circuit board26at a location spaced from the first electrically conductive film38. The first electrodes42a,42band the first electrically conductive lines43a,43bmay be made of a metal material such as silver, copper, or the like.

A pair of first electrically conductive pads46,46are formed on the front surface of the lower base member35at locations spaced form the first electrically conductive film38, the first electrodes42a,42band the first electrically conductive lines43a,43b.An electrically conductive line47is connected to the first electrically conductive pad46. The electrically conductive line47extends on the front surface of the lower base member35at a location spaced from the first electrodes42a,42band the first electrically conductive lines43a,43b.The electrically conductive line47is directed to the flexible printed circuit board26. The first electrically conductive pads46and the electrically conductive lines47may be made of a metal material such as silver, copper, or the like.

Referring also toFIG. 5, a transparent second electrically conductive film48extends over the back surface of the upper base member36. The second electrically conductive film48has a rectangular shape. The back surface of the upper base member36is exposed around the second electrically conductive film48. The second electrically conductive film48is located at a position opposed to the first electrically conductive film38. The second electrically conductive film48may be made of an indium-tin oxide (ITO) film, for example.

A second electrically conductive body49extends on the back surface of the upper base member36along the outer periphery of the upper base member36. The second electrically conductive body49includes a pair of second electrode51a,51band a pair of second electrically conductive line52a,52b.The second electrodes51a,51bare individually connected to the second electrically conductive film48. The second electrically conductive lines52a,52bare separately connected to the second electrodes51a,51b,respectively. The second electrodes51a,51bextend along the shorter sides of the rectangular second electrically conductive film48. The second electrically conductive film48thus extends between the second electrodes51a,51b.The second electrode51aserpentines along a straight line connecting a starting point54and an end point55. The starting point54is opposed to the starting point44of the first electrically conductive line43a. The end point55is opposed to the end point45of the first electrically conductive line43a.

The ends of the second electrically conductive lines52a,52bare connected to the second electrically conductive pads53,53. The second electrically conductive pads53are located on the back surface of the upper base member36at positions spaced from the second electrically conductive film48and the second electrodes51a,51b.The second electrodes51a,51b,the second electrically conductive lines52a,52band the second electrically conductive pads53may be made of a metal material such as silver, copper, or the like. When the lower base member35is coupled with the upper base member36with the aforementioned adhesive material37, the individual second electrically conductive pads53,53are connected to the corresponding first electrically conductive pads46,46, respectively. The second electrically conductive pads53,53are thus connected to the electrically conductive lines47,47on the lower base member35.

As shown inFIG. 6, when the upper base member36is placed on the lower base member35, the straight line connecting the starting point44and the end point45is aligned with the straight line connecting the starting point54and the end point55. The second electrode51aintersects across the first electrically conductive line43atwo or more times between the starting point54and the end point55. The lap is reduced between the first electrically conductive line43aand the second electrode51ato the utmost. Here, the second electrode51acrosses the first electrically conductive line43aat equal intervals.

As shown inFIG. 7, when the touch screen panel unit22is incorporated within the display enclosure17, the lower base member35is located along the front surface of the LCD panel unit23. The front surface of the upper base member36receives the cover21. The window opening18of the cover21is thus arranged on the front surface of the upper base member36. The electrically conductive line43aand the second electrode51aare located off the window opening18.

As described above, the adhesive material37is interposed between the first electrically conductive line43aand the second electrode51a.The adhesive material37may be an insulating double-sided adhesive sheet serving as an insulator layer. The adhesive material37serves to insulate the electrically conductive line43afrom the second electrode51a.The adhesive material37includes a substrate37aand adhesive layers37bformed on the front and back surfaces of the substrate37a.The substrate37amay be made of a resin material such as silicone. The adhesive layers37bmay be made of an acrylic resin material. The substrate37aserves to hold an urging force acting on the upper base member36from the cover21.

For example, assume that an application software is to be booted up based on the input manipulation of the touch screen panel unit22. An icon representing the application software is displayed on the screen of the LCD panel inside the window opening18. The position of the icon is determined based on the x- and y-coordinate.

Now, if the user touches the upper base member36of the touch screen panel unit22at the icon, the upper base member36deforms at the corresponding touch position. The deformation of the upper base member36causes the second electrically conductive film48on the upper base member36to contact the first electrically conductive film38on the lower base member35. An electric potential gradient is induced in the second electrically conductive film48on the upper base member36, so that the x-coordinate of the touch position can be determined. Voltage is applied to the second electrically conductive film48through the electrically conductive lines47, the second electrically conductive line52a,52band the second electrode51a,51b.The electric potential of the touch position is taken out from the first electrically conductive film38. The electric potential of the touch position is utilized to determine the x-coordinate.

An electric potential gradient is likewise induced in the first electrically conductive film38on the lower base member35, so that the y-coordinate of the touch position can be determined. Voltage is applied to the first electrically conductive film38through the first electrically conductive line43a,43band the first electrode42a,42b.The electric potential of the touch position is taken out from the second electrically conductive film48. The electric potential of the touch position is utilized to determine the y-coordinate. The x- and y-coordinates are supplied to the CPU. The CPU observes the relationship between the x- and y-coordinates and the aforementioned x- and y-coordinates. If the correspondence is confirmed, the CPU operates to boot the application software.

Next, a brief explanation will be made on a method of making the touch screen panel unit22. The lower and upper base members35,36are first separately prepared. The first and second electrically conductive films38,48have been evaporated on the lower and upper base members35,36, respectively. The first electrically conductive body41is then formed on the lower base member35along the periphery. The second electrically conductive body49is formed on the upper base member36along the periphery. In this case, silver or copper paste is first printed on a predetermined substrate in patterns corresponding to the electrodes and the electrically conductive lines. The first electrically conductive line43aand the second electrode51amay be shaped in a meander. The silver or copper paste gets hardened based on an applied heat. The patterned electrodes and electrically conductive lines are then transferred from the substrate to the lower and upper base members35,36at predetermined positions. The dot spacers39are formed on the upper surface of the first electrically conductive film38. A resin material may be applied to predetermined positions to establish the individual dot spacers39, for example. The adhesive material37is thereafter interposed between the lower and upper base members35,36. The upper base member36is in this way coupled to the lower base member35.

A user of the notebook personal computer11often grasps the periphery of the display apparatus14. A larger urging force is applied to the upper base member36from the cover21. The urging force acts on the first electrically conductive line43aand the second electrode51a.Since the lap is reduced between the first electrically conductive line43aand the second electrode51a, any contact is to the utmost prevented between the first electrically conductive line43aand the second electrode51a.The touch screen panel unit22keeps normally operating.

In addition, when the urging force is received on the upper base member36from the cover21, the second electrode51ais urged toward the first electrically conductive line43a. The second electrode51and the first electrically conductive line43aare set symmetric relative to the straight line connecting the starting points44,54and the end points45,55, so that a lateral shift can be prevented between the second electrode51and the first electrically conductive line43aalong the surface of the upper and lower base members35,36.

The touch screen panel unit22may be employed not only in the notebook personal computer11but also in any type of electronic apparatus such as a personal digital assistance (PDA), a point-of-sales (POS) terminal, a global positioning system (GPS) terminal, a facsimile machine, a copying machine, a car navigation system, and the like.