Patent Application
20110261074
Embodiments described herein relate generally to a technique for controlling an input from a touch panel.
In a mode other than a power-saving mode, a touch panel used in an image processing apparatus or the like is always in an energized state.
This has a defect (problem) that wasteful power is consumed.
An input apparatus includes a display part, a touch panel and a touch panel control part. The display part displays one or plural button images. The touch panel is arranged at an upper part of a display area of the display part. The touch panel control part supplies power to the touch panel so that the power is supplied to an area which is an area of the touch panel and corresponds to an area of the button image displayed on the display part.
Hereinafter, a description will be made with reference to the drawings. In the following description, it is assumed that an arrangement position of a button is previously defined.
The image processing apparatus 100 includes a control panel unit 30 (input apparatus) that displays control content and receives instructions from a user.
Besides, the image processing apparatus 100 includes an image reading part 101 to scan and read an image of a sheet document and a book document, and an image forming part 102 to form the image read by the image reading part 101 or an image of image data received from the outside on a sheet.
With respect to the details of the control panel unit 30, an example in which a light-emitting element and a light-receiving element are used will be described in a first embodiment, and an example in which a resistive film is used will be descried in a second embodiment.
Buttons 1 to 4 are images of input buttons displayed on the LCD screen of the display part 71. The touch panel 33 includes light-emitting elements 11A and 11E at the left part and the upper part, and light-receiving elements 12A and 12B at the right part and the lower part.
As the position detection of the touch panel part 72, the upper light-emitting element 11B and the lower light-receiving element 12B are used for detection in a horizontal direction, and the left light-emitting element 11A and the right light-receiving element 12A are used for detection in a vertical direction. The light-receiving elements 12A and 12B receive light from the light-emitting elements 11A and 11B. The position detection is performed in such a way that the light is shielded by a finger tip of a user or a pen tip, and the light-receiving elements 12A and 12B can not receive the light of the light-emitting elements 11A and 11B.
In the light-emitting elements 11A and 11B and the light-receiving elements 12A and 12B, many light-emitting elements and light-receiving elements are used in order to detect the whole area of the LCD screen.
On the LCD screen of
In
The arrangement of the buttons 5 to 8 of
As compared with the buttons 2 to 4, the button 1 of
The touch panel 33 and the LCD display part 35 have an overlapping structure in the up-and-down direction, and the touch panel 33 is located at the upper part, and the LCD display part 35 is located at the lower part.
The touch panel 33 includes a transparent member 13 (glass) to allow light from the lower LCD display part 35 to pass through, a light-emitting element D (LED) as a touch detection light source, and a light-receiving element T (phototransistor) to receive light of the touch detection light source.
The light (touch sensor light) outputted from the light-emitting element D passes through an upper part of the transparent member 13 and reaches the light-receiving element T.
Next, an inner structure of the LCD display part 35 will be described. The light outputted from a light source 23 for light emission is guided toward an upper part of the LCD display part 35 by a light guide plate 22.
In the guided light, only light having a specific direction is allowed to pass through by a polarizing plate 21.
The light passing through the polarizing plate 21 passes through a transparent electrode (pixel) 20, an alignment film 19, a liquid crystal layer 18, an alignment film 17, a transparent electrode (common) 16 and a color filter polarizing plate 15, and reaches an upper polarizing plate 14.
The light reaching the polarizing plate 14 is divided into a light (transmitted light) passing through the polarizing plate 14 and a light (non-transmitted light) not passing through the polarizing plate 14, and only the transmitted light reaches the transparent member 13 and is recognized as an emitted light by the user.
The liquid crystal layer 18 is sandwiched between the alignment films 17 and 19 in the up-and-down direction, and the two alignment films 17 and 19 are arranged in the directions in which the phases are different by 90 degrees.
The liquid crystal layer 18 is in a state where liquid crystal molecules are twisted by 90 degrees in accordance with the phases of the alignment films 17 and 19. The phase of the polarizing plate 21 is equal to the phase of the alignment film 19, and the phase of the polarizing plate 14 is equal to the phase of the alignment film 17. The phase of the polarizing plate 21 and the alignment film 19 is different from the phase of the polarizing plate 14 and the alignment film 17 by 90 degrees.
The electrode (pixel) 20 exists under the alignment film 19, and the electrode (common) 16 exists on the alignment film 17. When a voltage is not applied between the electrode (pixel) 20 and the electrode (common) 16, the liquid crystal molecules are twisted by 90 degrees. Thus, when the light which passes through the polarizing plate 21 and in which the phase is uniformed passes through the liquid crystal layer 18, the light becomes the light in which the phase is twisted by 90 degrees. The light reaches the polarizing plate 14 and passes through the polarizing plate 14.
When a voltage is applied between the electrode (pixel) 20 and the electrode (common) 16, the liquid crystal molecules of the liquid crystal layer 18 are in a parallel state in which the twist of 90 degrees is returned. Thus, when the light which passes through the polarizing plate 21 and in which the phase is uniformed passes through the liquid crystal layer 18, the light having the same phase reaches the polarizing plate 14. Thus, the light different in phase from the polarizing plate 14 by 90 degrees can not pass through the polarizing plate 14.
The light (transmitted light) passing through the polarizing plate 14 is the light when the voltage is not applied between the electrode (pixel) 20 and the electrode (common) 16. On the other hand, the light (non-transmitted light) not passing through the polarizing plate 14 is the light when the voltage is applied between the electrode (pixel) 20 and the electrode (common) 16.
The electrode (pixel) 20 is controlled in position units of color filters corresponding to three primary colors of a pixel, and a potential difference occurs between the electrode (pixel) 20 and the electrode (common) 16.
The position where the potential difference occurs and the position where there is no potential difference are controlled, so that the control is performed as to whether light is allowed to pass through to the upper part of the polarizing plate 14.
The control panel unit 30 includes a touch panel control circuit 32 to control the detection (hereinafter referred to as touch detection) of touch by a user's finger tip or a pen tip, and the touch panel 33, a LCD control circuit 34 to control screen display, and the LCD display part 35 to perform screen display. Besides, the control panel unit 30 includes the processor 31 shown in
A rectangular area defined by connecting (Dxa1, Dxb1), (Dxa2, DYb1), (Dxa1, DYb2) and (Dxa2, DYb2) in the area of
Drive circuits 41 (X0 to Xp) to control display in the horizontal direction and drive circuits 42 (Y0 to Yq) to control display in the vertical direction are provided.
An intersection point in the vertical and horizontal directions is a display control object, and the drive circuits 41 and the drive circuits 42 change and control the display control object in time division. A rectangular area defined by connecting four points of (X0, Y0), (Xp, Y0), (X0, Yq) and (Xp, Yq) becomes a displayable area. A rectangular area defined by connecting (Xc1, Yd1), (Xc2, Yd1), (Xc1, Yd2) and (Xc2, Yd2) in the displayable area of
Liquid crystal (the liquid crystal layer 18 of
Since the resolution of the touch detection is different from the resolution of the LCD display part, in order to perform the touch detection and the LCD display in the same area, it is necessary to maintain a relation of
a2−a1=(c2−c1)×(n+1)/(p+1)
b2−b1=(d2−d1)×(m+1)/(q+1)
(with respect to the respective variables of the above expressions, see
The touch detection drive circuit 51 includes touch detection position shift registers (Sx0 to Sxn, SY0 to SYm) to generate a timing when a combination of a light-emitting element D and a light-receiving element T is driven in sequence, and touch detection area registers (Ex0 to Exn, EY0 to EYm) to determine an area of a light-emitting element and a light-receiving element in which the touch detection is performed. Besides, the touch detection drive circuit 51 includes light-emitting element drive circuits (Vx0 to Vxn, VY0 to VYm) to control whether a voltage is applied to a light-emitting element D to emit light or a voltage is not applied not to emit light, and light-emitting elements (Dx0 to Dxn, DY0 to DYm). The touch detection drive circuit 51 includes light-receiving element power supply control circuits (Px0 to Pxn, PY0 to PYm) to control power supply to each light-receiving element T, and light-receiving elements (Tx0 to Txn, TY0 to TYm). The touch detection drive circuit 51 includes touch detection position information registers (Lx0 to Lxn, LY0 to LYm) to hold position information of touch detection, and a touch detection interrupt register (Fint) to generate an interrupt at the time of touch detection. The touch detection drive circuit 51 outputs a touch detection interrupt signal (INT) to the processor 31.
Besides, the touch detection drive circuit 51 includes timing registers (Fe1, Fe2) to generate an end timing of touch detection in the vertical direction after the touch detection in the horizontal direction is performed, and a clear register (Fclr) to generate a clear signal of the control circuit after the touch detection in the vertical direction is ended after the touch detection in the horizontal direction is performed. The touch detection drive circuit 51 includes a restart register (Fstart) to restart the touch detection in the vertical direction and the horizontal direction after the touch detection in the vertical direction is ended after the touch detection in the horizontal direction is performed. The touch detection drive circuit receives a clear signal (CLR) to clear the respective registers from the processor 31.
Besides, the touch detection drive circuit 51 receives a touch detection start signal (Start), which is a signal for starting the touch detection and is generated at the writing timing of the processor 31, from the processor 31.
The touch detection drive circuit 51 writes area data outputted from the processor 31 into the touch detection area registers (Ex0 to Exn, EY0 to EYm) at the timing of a touch detection area data writing signal (WRen).
The touch detection area data writing signal (WRen) is a signal generated (a generation circuit is not shown) from a writing signal (not shown) outputted from the processor 31, and is a signal by which the processor 31 writes data into the touch detection area registers (Ex0 to Exn, EY0 to EYm).
The touch detection drive circuit 51 outputs the data of the touch detection position information registers (Lx0 to Lxn, LY0 to LYm) to the processor 31 at the timing of a touch detection position information read signal (RDen).
The touch detection position information read signal (RDen) is a signal generated (a generating circuit is not shown) from a read signal (not shown) outputted from the processor 31, and is a signal by which the processor 31 reads data from the touch detection position information registers (Lx0 to Lxn, LY0 to LYm).
The touch detection drive circuit 51 operates in synchronization with a touch detection drive circuit basic clock (CLK) for operating the touch detection drive circuit of the touch panel.
The start timing of the touch detection is the time when the touch detection start signal (Start) outputted by the processor 31 is in a state of “1” (the Start signal is in the state of “1” only for 1 clk period).
When the Start signal of “1” is inputted to the touch detection position shift register (Sx0), the output state of “1” is shifted in sequence of Sx0, Sx1, Sx2, . . . , Sxn, SY0, SY1, SY2, . . . , SYm) at each clock of the touch detection drive circuit basic clock (CLK).
The light-emitting element drive circuits (Vx0 to Vxn, VY0 to VYm) drive the light-emitting elements D (Dx0 to Dxn, DY0 to DYm) to output light at the timing when the output states of the touch detection position shift registers (Sx0 to Sxn, SY0 to SYm) are “1”, and the outputs of the touch detection area registers (Ex0 to Exn, EY0 to EYm) are “1”.
At the same timing, the power is supplied to the respective light-receiving elements T from the light-receiving element power supply control circuits (Px0 to Pxn, PY0 to PYm).
When the touch panel 33 is not in the touch state, the light outputted from the light-emitting element D is inputted to the light-receiving element T (Tx0 to Txn, TY0 to TYm), and “1” indicating the light reception state is outputted.
When the touch panel 33 is in the touch state, since the light outputted from the light-emitting element D (Dx0 to Dxn, DY0 to DYm) is not inputted to the light-receiving element T (Tx0 to Txn, TY0 to TYm), the light-receiving element T outputs “0” indicating the light non-reception state.
When the light-receiving element T is in the light non-reception state “0” at the timing when the output of the touch detection area register (Ex0 to Exn, EY0 to EYm) is “1” (state where the light outputted from the light-emitting element is not inputted to the light-receiving element by a light shielding member, that is, the touch panel is in the touch state), the touch detection position information register (Lx0 to Lxn, LY0 to LYm) causes the value of the corresponding register to become “1” at the next CLK timing and holds it. The held state is held until the start of next touch detection.
When the touch detection in the horizontal direction (transition in sequence of Sx0, Sx1, Sx2, . . . , Sxn) and the touch detection in the vertical direction (transition in sequence of SY0, SY1, SY2, . . . , SYm) are ended, the timing register (Fe1) becomes “1”. When at least one of the touch detection position information registers (Lx0 to Lxn) is in the “1” state, and at least one of the touch detection position information registers (LY0 to LYm) is in the “1” state, “1” is held in the touch detection interrupt register (Fint). The touch detection interrupt register (Fint) maintains “1” unless the clear signal (CLR) is inputted.
When “1” is held in the touch detection interrupt register (Fint), the touch detection drive circuit 51 outputs the touch detection interrupt signal (INT)=“1” to the processor 31, and an interrupt occurs in the processor 31.
The processor 31 reads the touch detection position information registers (Lx0 to Lxn, LY0 to LYm) in the touch detection interrupt process, and specifies the touch position.
The processor 31 generates the clear signal (CLR) in the touch detection interrupt process and releases the interrupt (touch detection interrupt signal (INT)=“0”).
After the touch detection interrupt process is ended, the processor 31 outputs the touch detection start signal (Start) of “1” in order to restart the next touch detection.
On the other hand, when the touch detection in the horizontal direction (transition in sequence of Sx0, Sx1, Sx2, . . . , Sxn) and the touch detection in the vertical direction (transition in sequence of SY0, SY1, SY2, . . . , SYm) are ended, the timing register (Fe1) becomes “1”. At this time, when there is no register of the state of “1” in the touch detection position information registers (Lx0 to Lxn) and there is no register of the state of “1” in the touch detection position information registers (LY0 to LYm) (state where there is no touch), or when there is no register of the state of “1” in the touch detection position information registers (Lx0 to Lxn) or there is no register of the state of “1” in the touch detection position information registers (LY0 to LYm) (in the case of touch erroneous detection), “0” is held in the touch detection interrupt register (Fint) (touch detection interrupt does not occur: the touch detection interrupt signal (INT)=“0” is outputted).
When the touch detection interrupt signal (INT) is “0”, the timing register 1 (Fe2) becomes “1” at the next CLK, the clear register (Fclr) becomes “1” at the next CLK, and the respective registers are cleared at the next CLK. The touch detection start signal (Start) becomes “1” at the timing when the respective registers are cleared, and the touch detection in the horizontal direction and the vertical direction is started at the next CLK.
The area of the input button of the LCD display part 35 is a position corresponding to the touch detection area ((x1, Y1) to (x3, Y2)) of the touch panel 33. The light-emitting elements (Dx1 to Dx3) and the light-receiving elements (Tx1 to Tx3) in the horizontal direction, and the light-emitting elements (DY1 to DY2) and the light-receiving elements (TY1 to TY2) in the vertical direction are used in the touch detection of the input button.
The processor 31 generates a clear signal (CLR) and brings the touch detection drive circuit 51 into the initial state. The clear signal (CLR) is generated by a circuit not shown in
The processor 31 sets touch detection effectiveness (“1”) or touch detection ineffectiveness (“0”) to the initialized touch detection are registers ((Ex0 to Exn, EY0 to EYm)=“0”) in accordance with the touch detection area. In this example, the X direction: EX0=0, EX1 to EX3=1, EX4 to EXn=0, Y direction: EY0=0, EY1 to EY2=1, EY3 to EYm=0 are established.
The processor 31 generates the touch detection start signal (Start) and starts the touch detection. The touch detection start signal (Start) is generated by a circuit not shown in
By the touch detection start signal (Start), the touch detection position shift register transits to the “1” state in units of 1 CLK time (transition in sequence of Sx0, Sx1, Sx2, . . . , Sxn, SY0, SY1, SY2, . . . , SYm).
The light-emitting element D emits light at the timing when the touch detection area register is “1” and the touch detection position shift register is “1”. When receiving the light, the light-receiving element T outputs “1”.
At the same timing, the light-receiving state or non-detection state=“0”, the light non-reception state=“1” is inputted to the inputs of the touch detection position information registers (Lx0 to Lxn, LY0 to LYm). After 1 CLK, the input state is held in the touch detection position information registers (Lx0 to Lxn, LY0 to LYm).
Since there is no touch state in the first touch detection, “0” is held in all outputs of the touch detection position information registers (Lx0 to Lxn, LY0 to LYm).
When all the outputs of the touch detection position information registers (Lx0 to Lxn) are in the state of “0”, or all the outputs of the touch detection position information registers (LY0 to LYm) are in the state of “0”, the timing register (Fe1) is “1”, and “0” is held in the touch detection interrupt register (Fint) at the rising timing of the touch detection drive circuit basic clock (CLK). Thus, the touch detection interrupt does not occur in the processor 31.
When the touch detection interrupt does not occur in the processor 31, the timing register (Fe2) is “1”. The clear register (Fclr)=“1” is outputted for 1 CLK time at the rising timing of the touch detection drive circuit basic clock (CLK), and the outputs of the touch detection position information registers (Lx0 to Lxn, LY0 to LYm) are cleared. When 1 CLK passes after the outputs of the touch detection position information registers (Lx0 to Lxn, LY0 to LYm) are cleared, the output of the restart register (Fstart) becomes “1”, and the touch detection is again started.
Since there is a touch state in the second touch detection, “1” is held in the output of the touch detection position information register (Lx2, LY1). When the OR output of the touch detection position information registers (Lx0 to Lxn) is “1”, and the OR output of the touch detection position information registers (LY0 to LYm) is “1”, the timing register (Fe1) is 1, and “1” is held in the touch detection interrupt register (Fint) at the rising timing of the touch detection drive circuit basic clock (CLK). Thus, the touch detection interrupt occurs in the processor 31. While “1” is held in the touch detection interrupt register (Fint), “0” is held in the outputs of both the clear register (Fclr) and the restart register (Fstart). Thus, the touch detection becomes the stop state.
In the touch detection interrupt process, the processor 31 reads the values of the touch detection position information registers (Lx0 to Lxn, LY0 to LYm) at the timing of the touch position information read signal (RDen)=1.
In the touch detection interrupt process, the processor 31 generates the clear signal (CLR), and brings the touch detection drive circuit 51 into the initial state. At the time of the initialization, the touch detection interrupt register (Fint) becomes the state of “0”, and the touch detection interrupt process is ended. After the touch detection interrupt process is ended, the processor 31 generates the touch detection start signal (Start)=“1”, and again starts the touch detection.
When the input of the light-emitting element drive circuit (Vx0 to Vxn, VY0 to VYm) is “1”, the ON state occurs between C-E of a transistor (Q2), the power voltage VCC is applied and the light-emitting element D (Dx0 to Dxn, DY0 to DYm) emits light (light-emitting state). When the input is “0”, the off state occurs between C-E of the transistor (Q2), and the power voltage VCC is not applied. Thus, the light-emitting element D (Dx0 to Dxn, DY0 to DYm) does not emit light (non-light-emitting state).
The light-emitting element D (Dx0 to Dxn, DY0 to DYm) emits light (light-emitting state) when the power voltage VCC from the light-emitting element drive circuit (Vx0 to Vxn, VY0 to VYm) is applied. The light-emitting element D does not emit light (non-light-emitting state) when the power voltage VCC from the light-emitting element drive circuit (Vx0 to Vxn, VY0 to VYm) is not applied.
In the light-receiving element power supply control circuit (Px0 to Pxn, PY0 to PYm) to control the power supply to the light-receiving element T (Tx0 to Txn, TY0 to TYm), when the input is “1”, the ON state occurs between S-D of a FET (Q3), and the power voltage VCC is supplied to the light-receiving element T (Tx0 to Txn, TY0 to TYm) (VCC supply state). When the input is “0”, the off state occurs between S-D of the FET (Q3), and the power voltage VCC is not supplied to the light-receiving element T (Tx0 to Txn, TY0 to TYm) (VCC non-supply state).
When receiving the light from the light-emitting element D (Dx0 to Dxn, DY0 to DYm) in the state (VCC supply state) where the power voltage VCC is supplied from the light-receiving element power supply control circuit (Px0 to Pxn, PY0 to PYm), the light-receiving element T (Tx0 to Txn, TY0 to TYm) outputs “1”. When not receiving the light from the light-emitting element D (Dx0 to Dxn, DY0 to DYm), the light-receiving element T (Tx0 to Txn, TY0 to TYm) outputs “0”. In the state (VCC non-supply state) where the power voltage VCC is not supplied from the light-receiving element power supply control circuit (Px0 to Pxn, PY0 to PYm), the light-receiving element T (Tx0 to Txn, TY0 to TYm) outputs “0”.
All the light-emitting elements D (Dx0 to Dxn, DY0 to DYm) become the light-emitting states in sequence one by one. The light-receiving element power supply control circuits (Px0 to Pxn, PY0 to PYm) corresponding to the light-emitting elements D (Dx0 to Dxn, DY0 to DYm) also become the power VCC supply states in sequence one by one.
The light-emitting element D (Dx0) is always in the non-light-emitting state. The light-emitting elements D (Dx1 to Dx3) become the light-emitting state in sequence one by one.
The light-emitting elements D (Dx4 to Dxn) are always in the non-light-emitting state. The light-emitting element D (DY0) is always in the non-light-emitting state. The light-emitting elements D (DY1 to DY2) become the light-emitting state in sequence one by one. The light-emitting elements D (DY3 to DYm) are always in the non-light-emitting state.
The light-receiving element power supply control circuit (Px0) corresponding to the light-emitting element D (Dx0) is always in the power VCC non-supply state. The light-receiving element power supply control circuits (Px1 to Px3) corresponding to the light-emitting elements D (Dx1 to Dx3) become the power VCC supply state in sequence one by one. The light-receiving element power supply control circuits (Px4 to Pxn) corresponding to the light-emitting elements D (Dx4 to Dxn) are always in the power VCC non-supply state.
The light-receiving element power supply control circuit (PY0) corresponding to the light-emitting element D (DY0) is always in the power VCC non-supply state. The light-receiving element power supply control circuits (PY1 to PY2) corresponding to the light-emitting elements D (DY1 to DY2) become the power VCC supply state in sequence one by one. The light-receiving element power supply control circuits (PY3 to PYm) corresponding to the light-emitting elements D (DY3 to DYm) are always in the power VCC non-supply state.
After the initial screen is displayed by the LCD display part 35 (ACT 1), the processor 31 clears (CLR) the touch detection drive circuit (ACT 2).
The processor 31 sets a touch detection area corresponding to an input button on the initial screen (Ex0 to Exn, EY0 to EYm) (ACT 3).
The processor 31 enables the touch detection interrupt (INT) and this enables the processor 31 to receive the interrupt (since the interrupt enable is set by the register on the processor 31 side, it is not shown in
The processor 31 starts the touch detection (Start) (ACT 5).
The processor 31 is placed in a state for waiting for the occurrence of the touch detection interrupt (INT) (ACT 6, loop of N).
When the touch detection interrupt (INT) occurs (ACT 6, Y), the processor 31 starts the touch detection interrupt process.
In the touch detection interrupt process, the processor 31 disables the touch detection interrupt (INT) (ACT 7).
The processor 31 reads the touch detection position in the touch detection interrupt process (the processor 31 reads the touch detection position information registers (Lx0 to Lxn, LY0 to LYm)) (ACT 8).
The processor 31 specifies a touched input button from the touch detection position information, and changes the LCD display part 35 to the screen according to the input button (ACT 9).
The processor 31 sets the touch detection area according to the input button on the new display screen (ACT 10). Since the touch detection in the touch detection area registers (Ex0 to Exn, EY0 to EYm) is suspended at the time of occurrence of the touch detection interrupt, the processor 31 clears the touch detection drive circuit 51 and enables the touch detection to be reopened (ACT 11).
The processor 31 enables the touch detection interrupt (INT) (ACT 12), and restarts the touch detection (Start) (ACT 13).
The processor 31 is placed in the state for waiting for the touch detection interrupt (INT) (returns to ACT 6).
In the first embodiment, the description is made on the method in which the user's button depression is detected by detecting cutoff of light by using the system in which the power of only the light-emitting element and the light-receiving element corresponding to the position of the button image is turned ON. In a second embodiment, a description will be made on a method in which the user's depression is detected by using a resistive touch panel.
In the 4-wire resistive touch panel, the touch position “a” is detected by the method described in
The 4-wire resistive touch panel 61 is divided into a 5×5 matrix form, and the touch detection is performed in units of each area. A conductive layer to which voltage is applied and an area where the voltage is detected are changed for the five rectangular lower conductive layers and the five rectangular upper conductive layers, so that a detected area is determined, and the detailed position detection of the touch position in the area is performed.
In the 4-wire resistive touch panel 61, the ON and OFF operation (ON and OFF operation of each switch shown in
Here, a description will be made on the detection in the vertical direction when a position “b” of
Incidentally, although the detection in the vertical direction is explained here, the detection in the horizontal direction can also be performed by taking the explanation in
In the above respective embodiments, the technique described above can be applied also to a button which is grayed out (display state in which although the display is faintly visible, the depressing operation is not acceptable), for example, when there is no depression right to a specific button, or when a button becomes depressible by performing a specific operation. For example, like a button 9 shown in
It is conceivable that all power sources of the light-emitting elements and the light-receiving elements corresponding to the area of the button image are not turned on, but only part of the power sources are turned on.
Incidentally, the button includes an image, such as an icon, which can be selected by the user. Besides, in the above respective embodiments, an ASIC (Application Specific Integrated Circuit) may be mounted. Besides, the processor 31 may load a program previously stored in a nonvolatile storage area of the memory 112 into a volatile storage area of the memory 112, and may perform arithmetic operation.
As described above in detail, according to the technique described herein, power is supplied only to a necessary portion of an input button image in the touch panel, and power is not supplied to an unnecessary portion. By adopting the structure as stated above, the power used in the touch panel can be reduced.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of invention. Indeed, the novel apparatus and methods described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the apparatus and methods described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.
This application is based upon and claims the benefit of priority from: U.S. provisional application 61/328,392, filed on Apr. 27, 2010; the entire contents all of which are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61328392 | Apr 2010 | US |
