Abstract:
A multifunction input device for use with a computer plotter system, word processing system, or Chinese hand-write recognition system, which includes a double-loop conductor array for use with a wireless battery-driven induction pen, a wireless non-battery induction pen, a static pen, a finger, and data processing circuit, wherein induction current and static current are produced upon approaching of the wireless induction pen, static pen, or finger, causing conductors of the double-loop conductor array to scan the position of the pen, and generate an enabling scanned signal, so that the XYZ coordinate values of the pen are sent to a host computer.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to an input device for use with a computer plotting system, word processing system, Chinese hand-write recognition system, etc., and more particularly to a multifunction input device, which can be used with any of a variety of input media. 
     A variety of input devices, including mice, digitizers, touch pads, etc., have been disclosed for use with computer plotting systems, hand-write recognition systems, etc., and have appeared on the market. These input devices have different advantages. A mouse uses a track ball or optical reflecting medium to detect XY coordinates. This kind of input device can only be used for coordinate movement. It cannot be used for hand-write recognition. A touch pad uses resistance means as a medium. Either of carbon powder type or ITO type, a touch pad wears quickly with use, and its sensitivity tends to be affected by ambient humility. The service life of a touch pad is short (normally below one hundred thousands). Due to these drawbacks, this kind of touch pad is not used in expensive notebook computers. Regular capacitive type touch pads, which are commonly used in notebook computers, are durable in use. However, the sensitivity of a capacitive type touch pad tends to be affected by swear or moisture. Further, regular digitizers are commonly equipped with a wired induction pen. Because the induction pen of a digitizer is secured in place by a wire, the wire may hinder the movement of the user&#39;s hand when operating the induction pen. Further, because a digitizer is for XY two-dimension detection only, it cannot detect the pressure of the pen, i.e., the pen cannot be operated as a writing brush. Further, there is known a wireless induction pen (battery-driven) for use as an input medium. This kind of battery-driven wireless induction pen is functional. However, because the service life of the battery is short, the battery must be frequently replaced. 
     SUMMARY OF THE INVENTION 
     The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a multifunction input device, which is practical for use with any of a variety of input media for XYZ three-dimension coordinates detection. According to the present invention, the multifunction input device comprises a double-loop conductor array for use with a battery-driven wireless induction pen, a non-battery type wireless induction pen, a static pen, and/or the finger. Coordinate movement and pen/finger pressure are detected by the double-loop conductor array, and processed through a processing circuit. The coordinate value thus obtained can be transmitted to a network TV or computer by infrared, or through UART, PS/2, or USB interface means for computer plotting, hand-write recognition, network TV system operation control. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIGS. 1A,  1 B,  1 C, and  1 D together form a system block diagram of the present invention. 
     FIG. 2 is a finger/static pen signal waveform chart according to the present invention. 
     FIG. 3 is a wireless induction pen (battery-driven type) signal waveform chart according to the present invention. 
     FIG. 4 is a wireless induction pen (non-battery type) signal waveform chart according to the present invention. 
     FIG. 5 is a button function and pen pressure (Z-axis) signal waveform chart according to the present invention. 
     FIGS. 6 and 6A together form a data transmission interface switching and power down mode waveform chart according to the present invention. 
     FIGS. 7A,  7 B, and  7 C illustrate structures of wireless induction pens and cursor mice according to the present invention. 
     FIG. 8 illustrates the arrangement of alternate sensor area type conductors and capacitive sensor area type conductors according to the present invention. 
     FIG. 9 illustrates concomitant application of a wireless induction pen and a finger according to the present invention. 
     FIG. 10 illustrates the application of a wireless induction pen to the LCD module according to the present invention. 
     FIG. 11 is a diagram showing how FIGS. 1A and 1B mate together. 
     FIG. 12 is a diagram showing how FIGS. 1C and 1D mate together. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS. 1A,  1 B,  1 C and  1 D, when system power is on, crystal circuit  16  provides CPU  17  with the necessary oscillating signal S, causing CPU  17  to work. When working, CPU  17  sends signal O to enable model set buffer  12 , then reads set status of model set buffer  12 . Upon receipt of status signal N from model set buffer  12 , CPU  17  sets the system form or switches the system to wireless induction pen (with or without battery) input mode, finger or static pen input mode, etc. At first, the system enters finger/static pen input mode. 
     When entered finger/static pen input mode, CPU  17  sends address line T to address buffer  18 , and provides signal Y to enable address buffer  18 , causing address buffer to send address signal W to scan sensor circuit  19 . Scan sensor circuit  19  sends signal X to X multiplexer  20  and Y multiplexer  23 , forming a complete scanning circuit. When a finger or static pen touches capacitance sensor area  22 , a voltage is induced at the touched address and detected by scan sensor circuit  19 . In order to detect the amount of static electricity carried by the finger or static pen, frequency signal must be applied to every conductor. Therefore, transmitting/receiving control signal i generated by timer generator circuit  24  is sent by model timer switch circuit  29  to transmitting/receiving circuit  30  for transmitting/receiving status signal control, enabling main frequency signal k to be sent from timer generator circuit  24  to transmitting/receiving circuit  30 . When transmitting/receiving control signal i is of transmitting status, transmitting/receiving circuit  30  sends main frequency signal k to model switch circuit A  27  and then X/Y switch circuit  26 , causing X/Y switch circuit  26  to provide signal X(d) and signal Y(e) to every conductor of capacitance sensor area  22 . When the finger or static pen approaches, a signal amount change occurs at the conductors carrying main frequency signal k, i.e., the voltage of conductor signal at the area touched by the finger or static pen becomes increased, and the area not touched by the finger or static pen is maintained at the fixed voltage level. At this time, transmitting/receiving control signal I is switched to receiving status, and static voltage signal s induced by the finger of static pen is transmitted to noise clear circuit  34  to match with clear reference frequency r from digital control circuit  25  in clearing noises from induced static voltage signal. The noises been cleared include external noises and transmitting/receiving switching noises. Noise cleared signal t thus obtained is sent to signal amplify circuit  35  for amplification. Amplified signal u is then sent from signal amplify circuit  35  to compare circuit  36 , enabling the most stable signal to be picked up. Stable signal V thus obtained from compare circuit  36  is then sent to digital control amplify circuit  37  via model switch circuit B  33 . The time of amplification of digital control amplify circuit  37  can be adjusted by control signal C from CPU  17 . If the intensity of scanned signal is low, the gain of digital control amplify circuit  37  is adjusted to the maximum status. On the contrary, if the intensity of scanned signal is high (saturated status), the gain of digital control amplify circuit  37  is adjusted to a lower level. Therefore, scanned signal is kept in the best position. The best static voltage signal x is then sent to integrator amplify circuit  38 , and integrated by integrator amplify circuit  38  into signal y, which is in turn amplified by pos XY amplify circuit  39  into signal z. Signal z is then sent to band pass filter  40 . Band pass filter  40  removes low/high noise frequency from signal z, and filtrates waveform of signal z, so as to provide pos XY A/D convert  41  with signal AA having a waveform similar to sine wave. Pos XY A/D convert  41  converts analog signal AA into TTL level pulse waveform of which the pulse width varies with movement of the finger or static pen on conductor loop area. The variation of the pulse width is indicative of the displacement of the finger or static pen. Pulse signal FF thus obtained is than sent to pos XY control circuit  45 , causing pos XY control circuit  45  to send interruption signal QQ to CPU  17 , and thus CPU  17  is informed to receive XY data coordinate produced by pos X/Y binary counter  49 . Upon receipt of interruption signal QQ, CPU  17  sends signal JJ to enable pos XY data buffer  52 , so as to obtain XY data SS from pos XY data buffer  52 . XY data SS thus obtained is computed by CPU  17 , and the XY coordinate value of the position of the finger or static pen at capacitance sensor area  22  is thus obtained. 
     The second input medium of the present invention is a wireless induction pen (non-battery type). The operation flow of the second input medium is outlined hereinafter. CPU  17  reads the status of model set buffer  12 . When entered wireless induction pen/cursor mouse (non-battery type) input mode, CPU  17  sends address line T to address buffer  18 , and provides signal Y to enable address buffer  18 , causing address buffer  18  to send address signal W to scan sensor circuit  19 . Scan sensor circuit  19  sends signal X to X multiplexer  20  and Y multiplexer  23 , forming a complete scanning circuit. When a wireless induction pen or cursor mouse touches alternate sensor area  21 , the position of the wireless induction pen or cursor mouse is detected. Because the wireless induction pen or cursor mouse has no self-provided battery power supply, it cannot transmit energy signal, and main frequency signal is provided through the conductors of alternate sensor area  21  to the wireless induction pen or cursor mouse, enabling the wireless induction pen or cursor mouse to accumulate energy and then to transmit signal. Therefore, transmitting/receiving control signal j generated by timer generator circuit  24  is sent to model timer switch circuit  29 , causing it to send signal e to transmitting/receiving circuit  30 . When transmitting receiving signal is of transmitting state, main frequency signal k is sent from timer generator circuit  24  to model switch circuit A  27  through signal line m, causing model switch circuit A  27  to send signal f to X/Y switch circuit  26 , and hence X/Y switch circuit  26  provides signal d and signal e to the conductor loop at alternate sensor area  21 , causing an induction effect to be produced subject to the distribution of the conductor loop. Therefore, main frequency signal k is sent to induction coil of wireless induction pen or cursor mouse, causing matched capacitance to accumulate energy. At this time, the wireless induction pen or cursor mouse is capable of transmitting energy. When transmitting/receiving signal is changed to receiving status, the wireless induction pen or cursor mouse immediately discharges energy to the conductors, and discharged energy is then scanned by scan sensor circuit  19 , and then sent through signal d and signal e to model switch circuit A  27  and transmitting/receiving circuit  30  via X/Y switch circuit  26 , and scanned signal n is then sent to  2  class amplify circuit  31  for amplification. Amplified signal O is then sampled by sample &amp; hold circuit  32 . Digital control circuit  25  provides reference signal P to sample &amp; hold circuit  32 . Sample &amp; hold circuit  32  picks up signal best waveform, and eliminates noises from signal during transmitting or receiving. Sampled signal g is sent to model switch circuit B  33 , causing model switch circuit B  33  to provide signal w to digital control amplify circuit  37 , therefore pressure analog/digital converter  44  obtains signal  00 . By means of control signal c, CPU  17  adjusts amplification or contraction of scanned signal, and controls signal x obtained from digital control amplify circuit  37 . Signal x is then sent by CPU  17  to integrator amplify circuit  38 , and integrated by integrator amplify circuit  38  into signal y, which is in turn amplified by pos. XY amplify circuit  39  and then filtered into smooth analog waveform AA by band pass filter  40 . Analog waveform AA is then sent to pos XY A/D convert  41 , and converted by pos XY A/D convert  41  into TTL level pulse signal FF of which the pulse width varies with movement of the pen or mouse. The variation of the pulse width is indicative of the displacement of the pen or mouse. Pulse signal FF thus obtained is than sent to pos XY control circuit  45  and carried into system frequency, causing pos XY control circuit  45  to send interruption signal QQ to CPU  17 . Upon receipt of interruption signal QQ, CPU  17  sends signal PP to XY data produced by pos X/Y binary counter  49 , so that XY variation data SS of the position of the pen or mouse is obtained through XY data buffer  52 . XY variation data SS is then computed through CPU  17 , and the XY coordinate value of the position of the pen or mouse at capacitance sensor area  22  is thus obtained. The waveforms produced by the related circuits during this operation flow are shown in FIG.  4 . 
     The last input medium is a wireless induction pen (battery-driven) or wireless mouse (battery-driven). CPU  17  reads the status of model set buffer  12 . When entered wireless induction pen/mouse (battery-driven) mode, the scanning circuit, which is formed of address buffer  18 , scan sensor circuit  19 , X multiplexer  20  and Y multiplexer  23  scans the position of the pen/mouse. Because the pen/mouse has self-provided battery power, the signal transmitting and receiving process is eliminated. Energy signal is directly sent from the pen/mouse through signal d and signal e to X/Y switch circuit  26 , and then sent through signal line f to model switch circuit  27 , causing model switch circuit  27  to provide induced signal g to  4  class amplify circuit  28  for amplification. Amplified signal h is then sent from  4  class amplify circuit  28  to model switch circuit B  33 , causing it to provide signal W to digital control amplify circuit  37 . In same manner, CPU  17  adjusts gain of signal W subject to signal  00 . Adjusted signal X is then processed through integrator amplify circuit  38 , pos. XY amplify circuit  39 , band pass filter  40 , and pos XY A/D convert  41 , and pulse signal FF is thus obtained indicative of the position of the pen/mouse. The pulse width of pulse signal FF varies with the movement of the pen/mouse. Pulse signal FF is then sent by pos XY A/D convert  41  to pos XY control circuit  45 , enabling system frequency to be carried therein. Upon receipt of pulse signal FF, pos XY control circuit  45  is driven to send interruption signal QQ to CPU  17 , causing CPU  17  to obtain XY data SS from pos data buffer  52 . XY data SS is then computed by CPU  17 , and the XY coordinate value of the position of the pen/mouse (battery-driven) is thus obtained. The waveforms produced by the related circuits during this operation flow are shown in FIG.  3 . 
     The system obtains the XY coordinate value of the position of the input medium placed on alternate sensor area  21  or capacitance sensor area  22  when scanning XY axes. In order to obtain the variation of Z-axis or On/Off status of the button, a special arrangement is required. When the position of Y-axis is obtained by means of scanning XY axes, the conductor Yn corresponding to the position of the pen/mouse is used as the reference conductor for detecting the variation of Z-axis, and CPU  17  uses conductor Yn for scanning Z-axis. Scanned signal is processed through circuits from  18  through  37  into waveform signal shown in FIGS. 2 and 3. The waveform of signal X (Z-axis) varies with the type of input medium. When a wireless electromagnetic pen (non-battery type) input medium is used, induced signal X is sent to phase detect circuit  42  for comparison with reference frequency signal BB from digital control circuit  25 . When the tip or button is not pressed, the energy frequency emitted from the pen is equal to reference frequency signal BB, and the potential of output signal is “LOW”. When the tip or button is pressed, the energy frequency emitted from the pen is different from reference frequency signal BB, and the potential of output signal is “High”. Subject to the potential of output signal, the On/Off status of the tip or button is known. After comparison, phase detect circuit  42  provides output signal CC to auto level detect circuit  43  for level adjustment. The distance (height) between the pen/mouse and alternate sensor area  21  affects the energy receiving/transmitting condition (strength) of the pen/mouse. Auto level detect circuit  43  automatically adjusts signal level subject to the level of the pen/mouse on alternate sensor area  21 . Level adjusted signal DD is then sent from auto level detect circuit  43  to compare circuit  47 , enabling compare circuit  47  to pick up signal HH from signal DD. Signal HH is further sent to Z S/H (Z-axis sample hold) circuit  48 . Z S/H circuit  48  picks up Z-axis signal II from signal HH, and sends it to Z counter circuit  51 , causing Z-counter circuit  51  to send signal MM to model selector circuit C  50 . Upon receipt of signal MM, model selector circuit C  50  provides tip or button status variation signal value NN to CPU  17  for On/Off status judgment. Because different tip or button induces different frequency, different signal value NN will be produced subject to the type of tip or button. Scanned signal X obtained from the procedure of scanning the pen/mouse (battery-driven type) is sent to amplify circuit  46  for amplification. Amplified waveform GG is then sent to compare circuit  47 , causing compare circuit  47  to output signal HH to Z S/H circuit  48 . Upon receipt of signal HH, Z S/H circuit  48  provides Z-axis signal II to Z counter circuit  51 , causing Z-counter circuit  51  to send signal LL to model selector circuit C  50 . Upon receipt of signal LL, model selector circuit C  50  provides tip or button status variation signal value NN to CPU  17  for On/Off status judgment. Z-axis pressure variation is controlled by another line. Further, output signal EE from band pass filter  40  is transmitted to pressure A/D convert  44 , causing it to provide pressure variation signal  00  to CPU  17 . CPU  17  obtains tip pressure start message subject to On/Off status of the tip, and data before and after pressure from signal  00  for calculating the variation of Z-axis pressure. With respective to finger or static pen detection, the system can only detect the presence of a finger or static pen. The button is at “On” status if the time in which the finger or static pen is induced, and then disappeared, and then induced again is within 0.5 second. On the contrary, the button is at “Off” status if the time in which the finger or static pen is induced, and then disappeared, and then induced again surpasses 0.5 second. The pressure variation is measured from pressure variation signal  00  from pressure A/D convert  44 . The produced by the related circuits during this operation flow are shown in FIG.  5 . 
     When the message of a particularly input medium is obtained by the system, XYZ coordinate value thus obtained is controlled through model set buffer  12  for different interface transmission. CPU  17  reads current interface transmission mode from model set buffer  12 . When current interface transmission is set for PS/2, interface select circuit  03  is switched to PS/2 interface transmission, enabling CPU  17  to send PS/ 2  data format to the host&#39;s PS/2 port  08  by means of signal TT and WW. If current interface transmission is set for UART, CPU  17  sends the data to interface select circuit  03  through TT, WW and XX, causing UART TXD circuit  05 , UART RXD circuit  06 , UART RTS circuit  07  to be connected to UART port  04 . If current interface transmission is set for USB (universal serial bus), CPU  17  communicates with USB port  09  via signal TT and WW and signal J and K. The above statement describes the connection to the host. The related waveforms are shown in FIG.  6 . 
     When interface select circuit  03  is set for infrared transmission, the power source  10  is battery +6V. Because the battery has a limited service life, the system uses a power save mode to extend the service life of the battery. When the system enters an input medium input mode, the X-Y-Z coordinate value of the position of the input medium is sent with signal TT to interface select circuit  03 , causing interface select circuit  03  to send signal A to TV IR (infrared) transmitting circuit  02  for transmission to the TV IR receiving unit  01  of the host network TV. The TV IR receiving unit  01  converts infrared data format to the interface format of the host, enabling the X-Y-Z coordinate value from the transmitter side to be sent to the inside of the host. If the input medium is left from the sensor area, CPU  17  immediately enters power down mode. Before entering power down mode, CPU  17  sends signal R to power control circuit  15  and reset switch circuit  14 . Upon receipt of signal R, power control circuit  15  turns off system component power (CPU and wake up timer circuit  13  excluded). When reset switch circuit  14  receives signal R after system power consumption has been reduced to the lower limit, reset switch circuit  14  is switched from Vcc to wake up timer circuit  13 . Wake up timer circuit  13  wakes up CPU  17  once per 0.25 second (when CPU  17  is in power down mode). If the input medium is placed on the sensor area gain, CPU  17  immediately enters normal operation mode after having been waked up, and outputs signal R to turn on all power source, enabling the system to work normally. When battery power drops below +4V, +4V voltage signal is sent with signal L to voltage detect circuit  11 . When the voltage at the input end of voltage detect circuit  11  drops below +4V, voltage detect circuit  11  turns signal M from “High” to “Low”, and informs CPU  17  of power low status, causing CPU  17  to trigger power low indicator LED (light emitting diode). The waveforms of the related circuits are shown in FIG.  6 A. 
     FIGS. 7A,  7 B and  7 C show structures of wireless induction pens and mice according to the present invention. The wireless induction pen shown in FIG. 7A has both ends workable. The structure of the body of this pen can be of battery-driven or non-battery type. Using a software program to give an instruction, the system is driven to switch battery-driven input medium input mode to non-battery input medium input mode. When the battery power of the battery-driven input medium is low, the user can switch battery-driven input medium input mode to non-battery input medium input mode, enabling the battery-driven input medium to work with the system continuously. FIGS. 7B and 7C show a battery-driven mouse and a non-battery mouse. The functions of these mice are similar to the wireless induction pen. 
     FIG. 8 illustrates alternate sensor area type double-loop conductor arrangement and capacitance sensor area type double-loop conductor arrangement. The circuit of alternate sensor area  21  detects wireless induction pen and mouse. Capacitive sensor area  22  detects finger and static pen. Because alternate sensor area  21  and capacitive sensor area  22  have a respective wiring for scan sensor circuit  19 , they are separated from each other, and the user can simultaneously use a finger and a wireless induction pen to draw lines on alternate sensor area  21  and capacitive sensor area  22 . FIGS. 9 and 10 show a finger and a wireless induction pen simultaneously used. According to the preferred embodiment of the present invention, capacitive sensor area  22  is disposed at the top, and alternate sensor area  21  is disposed at the bottom. Capacitive sensor area  22  is connected to circuit board by cable A. Alternate sensor area  21  is connected to circuit board by cable B. Circuit board detects the address coordinate of wireless induction pen, and then detects the address coordinate of finger, and then calculates XYZ coordinates value of each input medium. 
     FIG. 10 illustrates the application of a wireless induction pen to a LCD module. A regular commercially available notebook computer or PDA has a transparent face panel ITO covered on its LCD module. However, this transparent face panel wears quickly with use, causing great inconvenient to the user. For example, the impedance of the transparent face panel varies with time of use, ambient humility. When the transparent face panel starts to wear, the sensibility of the instrument is affected. In order to eliminate this problem, the present invention installs alternate sensor area  22  in the instrument below the LCD module. A wireless induction pen can send signal through the LCD module to the printed circuit board of alternate sensor area  22 , enabling the related data to be sent to main board unit, causing the host computer to show written characters on the LCD module. 
     It is to be understood that the drawings are designed for purposes of illustration only, and are not intended for use as a definition of the limits and scope of the invention disclosed.