Abstract:
A clock display having two linear parts. The first part has 6 positions for indicating the hours 1-6. Hour indications on the second part progress toward the position for hour 1 on the first part.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to a time display and, more specifically, to a time display for legibly indicating the time in an esthetically pleasing manner. 
     2. Description of Related Art 
     Time measurement technology has had steady progress in accuracy and efficiency, especially since the advent of electronics. Time display technology, however, has had no corresponding progress. The traditional clock face, having hour and minute hands progressing about a circular path, has been in continuous use for several hundred years. The traditional clock face is universally recognized, but is incongruous in certain contemporary settings, such as a offices and homes decorated in certain modern styles. Digital displays are also universally recognized, but are also incongruous in certain settings. 
     Various types of alternate time displays have been proposed. A problem with many of these alternate displays, however, is difficulty of interpretation. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a time display for legibly indicating the time in an esthetically pleasing manner. 
     To achieve this and other objects of the present invention, a clock system comprises a first display part with positions for indicating the hours 1-6, including a first position for indicating the hour 1, the first display part defining a first line; a second display part with positions for indicating the hours 7-12, respectively the second display part defining a second line substantially parallel to the first line, wherein a distance between the first position and the positions of the second display part is a decreasing function of the time corresponding to the positions of the second display part; and a signal generator coupled to the first display part and to the second display part. 
     According to another aspect of the present invention, there is a method of operating a clock system including a first display part with a first position for indicating the hour 1, the first display part defining a first line, a second display part with positions for indicating the hours 7-12, the second display part defining a second line substantially parallel to the first line. The method comprises the steps of generating a first signal to cause the first display part to indicate the hours 1-6; and generating a second signal to cause the second display to indicate time, such that a distance between the first position and the positions of the second display part is a decreasing function of the time corresponding to the positions of the second display part. 
     According to yet another aspect of the present invention, a clock system comprises: a first display part with a first position for indicating the hour 1, the first display part defining a first line; a second display part with positions for indicating the hours 7-12, the second display part defining a second line substantially parallel to the first line; means for generating a first signal to cause the first display part to indicate the hours 1-6; means for generating a second signal to cause the second display to indicate time, such that a distance between the first position and the positions of the second display part is a decreasing function of the time corresponding to the positions of the second display part. 
     According to yet another aspect of the present invention, a clock system comprises a plurality of first display areas for displaying minutes, each first display area defining a first polygon; and a plurality of second display areas for displaying second, each second display area defining a polygon overlapping one of the first polygons. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front view of a clock in accordance with a first preferred embodiment of the present invention. 
     FIG. 2 is a cross-sectional view taken along the line  2 — 2  in FIG.  1 . 
     FIG. 3 is a block diagram of some circuitry in the first preferred clock. 
     FIG. 4 is a flow chart expressing the functionality of a process performed by the circuitry shown in FIG.  3 . 
     FIG. 5 is a flow chart expressing the functionality of another process performed by the circuitry shown in FIG.  3 . 
     FIG. 6 is a timing diagram showing some signals generated by the circuitry shown in FIG.  3 . 
     FIG. 7 is a timing diagram corresponding to a part of FIG.  6 . 
     FIG. 8 is a view of the first preferred clock at a certain time. 
     FIG. 9 is a view of the first preferred clock at a different time. 
     FIG. 10 is a view of the first preferred clock at still a different time. 
     FIG. 11 is a view of a clock in accordance with a second preferred embodiment of the present invention. 
     FIG. 12 is a an enlarged view of a portion of the visual display of the second preferred clock. 
     FIG. 13 is a block diagram of some circuitry in the second preferred clock. 
     FIG. 14 is a block diagram of some circuitry shown in FIG. 13 in more detail. 
     FIG. 15 is a flow chart expressing the functionality of a process performed by the circuitry shown in FIG.  13 . 
     FIG. 16 is a the enlarged view of a portion of the visual display of the second preferred clock displaying a different time than that displayed in FIGS. 11 and 12. 
     FIG. 17 is a the enlarged view of a portion of the visual display of the second preferred clock displaying yet a different time than that displayed in FIGS. 11 and 12. 
     FIG. 18 is a the enlarged view of a portion of the visual display of the second preferred clock displaying yet a different time than that displayed in FIGS. 11 and 12. 
     FIG. 19 is a the enlarged view of a portion of the visual display of the second preferred clock displaying yet a different time than that displayed in FIGS. 11 and 12. 
     FIG. 20 is a view of a clock in accordance with a third preferred embodiment of the present invention. 
     FIG. 21 is a block diagram of some circuitry in the third preferred clock. 
    
    
     The accompanying drawings which are incorporated in and which constitute a part of this specification, illustrate embodiments of the invention and, together with the description, explain the principles of the invention, and additional advantages thereof. Throughout the drawings, corresponding parts are labeled with corresponding reference numbers. 
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     First Embodiment 
     FIG. 1 is a front view of clock  1 , and FIG. 2 is a side view of clock  1  taken along the line  2 — 2  in FIG.  1 . Clock  1  includes glass plate  10  and hour electrodes  101 ,  102 ,  103 ,  104 ,  105 ,  106 ,  107 ,  108 ,  109 ,  110 ,  111 , and  112  for indicating the hours of the day 1-12 respectively. Electrodes  101 ,  102 ,  103 ,  104 ,  105 , and  106  define a column for indicating the hours 1-6 respectively. Electrodes  107 ,  108 ,  109 ,  110 ,  111 ,  112  define another column for indicating the hours 7-12 respectively. 
     Glass plate  10  includes visible etching  19  and visible etching  23 . Visible etching  19  frames electrode group  17  including 30 electrodes for indicating the minutes 1-30 respectively. Electrode group  17  includes minute electrode  215  for indicating minute 15 of the hour, and minute electrode  230  for indicating minute 30 of the hour. 
     Visible etching  23  frames electrode group  21  including 29 electrodes for indicating the minutes 31-59 respectively. Electrode group  21  includes minute electrode  245  for indicating minute 45 of the hour. 
     In other words, clock  1  includes 59 positions corresponding to electrode group  17  and electrode group  21 , surrounding the hour positions, for indicating the minutes 1-59, respectively. Positions 1-30 define an outer right column, with position 1 at the top of the column and position 30 at the bottom of the column. Positions 31-59 define a left outer column, with position 31 at the bottom of the column and position 59 at the top of the column. The presence of a rectangle, in one of the positions, indicates that the minute is greater than or equal to the position number. 
     Glass plate  10  includes horizontal visible etchings  5 ,  6 ,  7 ,  8 , and  9  spaced in increments of 5 time units. Visible etching  5  intersects the visual path from the electrode for displaying minute 5 in group  17  and the electrode for displaying minute 55 in group  21 . Visible etching  6  intersects the visual path from the electrode for displaying minute 10 in group  17  and the electrode for displaying minute 50 in group  21 . Visible etching  7  intersects the visual path from the electrode for displaying minute 15 in group  17  and the electrode for displaying minute 45 in group  21 . Visible etching  8  intersects the visual path from the electrode for displaying minute 20 in group  17  and the electrode for displaying minute 40 in group  21 . Visible etching  9  intersects the visual path from the electrode for displaying minute 25 in group  17  and the electrode for displaying minute 35 in group  21 . 
     AC-DC converter  29  receives power from 60 Hz wall socket  30  via plug  31 . AC-DC converter  29  supplies a DC power signal to time processing circuitry  35 . Clock  1  includes a backup battery (not shown) to preserve the time in event of temporary disruption of the power from socket  30 . 
     In this Patent Application, the word circuitry encompasses both dedicated hardware and programmable hardware, such as a microprocessor CPU or reconfigurable logic array, in combination with programming data, such as sequentially fetched CPU instructions or programming data for a reconfigurable array. 
     Time processing circuitry  35  is electrically coupled to each of electrodes  101  through  112 ,  121  through  132 , the electrodes in electrode group  17 , and the electrodes in electrode group  21 , via electrically conductive signal paths  22  in glass plate  12 . 
     Glass plate  10  defines a thickness of approximately 0.5 inches. 
     Glass plate  12  is relatively thin and is bonded to glass plate  10 . Each of electrode groups  17  and  21 ; hour electrodes  101 ,  102 ,  103 ,  104 ,  105 ,  106 ,  107 ,  108 ,  109 ,  110 ,  111  and  112 ; and PM electrodes  121 ,  122 ,  123 ,  124 ,  125 ,  126 ,  127 ,  128 ,  129 ,  130 ,  131 , and  132  is on glass plate  12 . 
     Each hour electrode surrounds a respective PM electrode. Hour electrode  101  surrounds PM electrode  121 . Hour electrode  102  surrounds PM electrode  122 . Hour electrode  103  surrounds PM electrode  123 . Hour electrode  104  surrounds PM electrode  124 . Hour electrode  105  surrounds PM electrode  125 . Hour electrode  106  surrounds PM electrode  126 . Hour electrode  107  surrounds PM electrode  127 . Hour electrode  108  surrounds PM electrode  128 . Hour electrode  109  surrounds PM electrode  129 . Hour electrode  110  surrounds PM electrode  130 . Hour electrode  111  surrounds PM electrode  131 . Hour electrode  112  surrounds PM electrode  132 . 
     Glass plate  14  is bonded to glass plate  12  to define a chamber  25  between glass plate  12  and glass plate  14 . Liquid crystal material  26 , designated by hatch marks, occupies chamber  25 . Common electrode  15  is on glass plate  14 . Common electrode  15  is electrically connected to AC-DC converter  29 . 
     FIG. 3 shows time processing circuitry  35  in more detail. Timer module  37  maintains hours register  40  with the current hour, in the range 1-12. Timer module  37  maintains AM/PM register  41  with a 0 indicating AM and a 1 indicating PM. Hours decode module  42  decodes the values of hours register  40  and AM/PM register  41  to address and write values into hours latches  44 . Hours latches  44  include 12 latches for asserting voltages on hours electrodes  101 - 112  respectively. Hours latches  44  also includes 12 latches for asserting voltages on PM electrodes  121 - 132  respectively. 
     Timer module  37  maintains minutes register  46  with the current minute, in the range 1-59. Minute decode module  48  decodes the values of minutes register  46  and to address and write values into minutes latches  49 . Minutes latches  49  includes 59 latches: 30 latches for asserting voltages on the 30 electrodes in group  17  respectively, and 29 latches for asserting voltages on the 29 electrodes in group  21  respectively. 
     For the first embodiment of the present invention, it is presently preferred that timer module  37 , hours register  40 , AM/PM register  41 , hours decode module  42 , minutes register  46 , and minute decode module  48  be implemented with general purpose microprocessor CPU and instructions executed by the CPU. 
     FIG. 4 shows a process performed by hours decode module  42 . Decode module  42  selects a first hour position by setting a variable HOUR_POSITION equal to 1 (Step  5 ). Decode module  42  compares the current value of HOUR_POSITION to 12 (Step  10 ). If HOUR_POSITION is less than or equal to 12, decode module  42  compares HOUR_POSITION to the value in hours register  40  (Step  15 ). If the value of HOUR_POSITION is greater than the value in hours register  40 , decode module  42  clears the latch driving the hours electrode for the position indicated by HOUR_POSITION (step  20 ). In other words, in terms of the numbering scheme of FIG. 1, step  20  clears the latch driving hours electrode  100 +HOUR_POSITION. 
     Step  20  also writes a 0 into the latch driving the PM indicator for the hours position represented by HOUR_POSITION. In other words, step  20  writes a 0 into the latch driving PM electrode  120 +HOUR_POSITION. 
     If HOUR_POSITION is not greater than the value in hours register  40 , decode module  42  writes a 1 into the latch driving the hour electrode of the position indicated by HOUR_POSITION. In other words, decode module  42  writes a 1 into the latch driving electrode  100 +HOUR_POSITION. (Step  30 ). 
     Decode module  42  compares AM/PM register  41  to 1 (Step  40 ). If AM/PM register  41  is not equal to 1, decode module  42  writes a 0 into the latch driving the PM indicator for the hours position represented by HOUR_POSITION (step  50 ). In other words, step  50  writes a 0 into the latch driving PM electrode  120 +HOUR_POSITION. 
     If AM/PM register is equal to 1, decode module  42  writes a 1 into the latch driving the PM indicator for the hours position represented by HOUR_POSITION. In other words, decode module  42  writes a 1 into the latch driving electrode  120 +HOUR_POSITION. (Step  55 ). 
     Decode module  42  adds a 1 to the value of HOUR_POSITION (Step  60 ) and passes control to step  10  for processing of any remaining hour positions. 
     FIG. 5 expresses the functionality of minute decode module  48 . Decode module  48  selects a first minute position by setting a variable MINUTE_POSITION equal to 1 (Step  5 ). Decode module  48  compares the current value of MINUTE_POSITION to 59 (Step  10 ). If MINUTE_POSITION is less than or equal to 59, decode module  48  compares MINUTE_POSITION to the value in minutes register  46  (Step  15 ). If the value of MINUTE_POSITION is greater than the value in minutes register  46 , decode module  48  clears the latch driving the minute electrode for the position indicated by MINUTE_POSITION (step  20 ). 
     If MINUTE_POSITION is not greater than the value in minutes register  46 , decode module  48  writes a 1 into the latch driving the minute electrode of the position indicated by MINUTE_POSITION. (Step  30 ). 
     FIG. 6 is a timing diagram showing voltages applied to electrodes  101 - 112 , over a 24 hour period. The upper voltage level caused that portion of liquid crystal  26  opposite the electrode to be opaque. A low voltage causes that portion of liquid crystal  26  opposite the electrode to be relatively transparent. T 0  is 12 midnight, T 1  is 1am, T 2  is 2am, T 3  is 3am, T 4  is 4am, T 5  is 5am, T 6  is 6am, T 7  is 7am, T 8  is 8am, T 9  is 9am, T 10  is 10am, T 11  is 11pm, T 12  is noon, T 13  is 1pm, T 14  is 2pm, T 15  is 3pm, T 16  is 4pm, T 17  is 5pm, T 18  is 6pm, T 19  is 7pm, T 20  is 8pm, T 21  is 9pm, T 22  is 10pm, and T 23  is 11pm. 
     As shown at T 1 , the display area of electrodes  102 - 112  are caused to be transparent. The display area for electrode  101  is always opaque. 
     At a time T 2 , the display area for electrode  102  is caused to be opaque and to remain opaque until a time T 13 . At a time T 3 , the display area for electrode  103  is caused to be opaque, and to remain opaque until a time T 13 . At a time T 4 , the display area for electrode  104  is caused to be opaque, and to remain opaque until a time T 13 . At a time T 5 , the display area for electrode  105  is caused to be opaque, and to remain opaque until a time T 13 . At a time T 6 , the display area for electrode  106  is caused to be opaque, and to remain opaque until a time T 13 . At a time T 7 , the display area for electrode  107  is caused to be opaque, and to remain opaque until a time T 13 . At a time T 8 , the display area for electrode  108  is caused to be opaque, and to remain opaque until a time T 13 . At a time T 9 , the display area for electrode  109  is caused to be opaque, and to remain opaque until a time T 13 . At a time T 10 , the display area for electrode  110  is caused to be opaque, and to remain opaque until a time T 13 . At a time T 12 , the display area for electrode  111  is caused to be opaque, and to remain opaque until a time T 13 . At a time T 12 , the display area for electrode  112  is caused to be opaque, and to remain opaque until a time T 13 . 
     The functionality of hours decode module  42  causes the duty cycle of electrodes  101 - 112  to be a decreasing function of hour position. For example, electrode  101  in hour position 1 in on {fraction (12/12)} of the time. Electrode  102  in hour position 2 is on {fraction (11/12)} of the time. Electrode  103  in hour position 3 is on {fraction (10/12)} of the time. Electrode  104  in hour position 4 is on {fraction (9/12)} of the time, etc. 
     FIG. 7 is a diagram corresponding to a portion of FIG. 6 in more detail. FIG. 7 also shows voltages applied to minute electrode  215 , minute electrode  230 , and minute electrode  245 . At a time T 5 , each of the display areas of the minute electrodes is caused to be transparent. For example, at T 5  each of the display areas of minute electrodes  215 ,  230 , and  245  is caused to be transparent. 
     At a time T 5 . 25  (5:15am) the display area of minute electrode  215  is caused to be opaque and to remain opaque until time T 6 . At T 5 . 50  (5:30am) the display area of minute electrode  230  is caused to be opaque and to remain opaque until time T 6 . At T 5 . 75  (5:45am) the display area of minute electrode  245  is caused to be opaque and to remain opaque until a time T 6 . 
     Once a minute electrode is activated, the minute electrode remains activated until the beginning of the next hour. Thus, the functionality of minute decode module  48  causes the duty cycle of minute electrodes in electrode groups  17  and  21  to be a decreasing function of minute position. In other words, module  48  generates a signal to cause the number of displayed minute symbols to increase as function of time, until the beginning of the next hour. 
     FIG. 8 is a view of clock  1  at a time T 5 . 25  shown in FIG.  7 . 
     FIG. 9 is a view of clock  1  at a time T 5 . 75  shown in FIG.  7 . 
     FIG. 10 is a view of clock  1  at a time T 23  shown in FIG.  6 . 
     Second Embodiment 
     FIG. 11 is a front view of clock  2 . In FIG. 11, clock  2  is displaying of time of 5:15 AM and 13 seconds (5:15:13). 
     Glass plate  10  includes visible etching  19  and visible etching  23 . Visible etching  19  frames electrode group  18  including 30 pairs of electrodes for indicating the minutes 1-30 respectively, and for indicating the seconds 1-30 respectively. For example, electrode group  18  includes a pair of electrodes  301  and  401  for indicating minute 1 of the hour and second 1 of the minute; a pair of electrodes  302  and  402  for indicating minute 2 of the hour and second 2 of the minute; a pair of electrodes  303  and  403  for indicating minute 3 of the hour and second 3 of the minute; a pair of electrodes  312  and  412  for indicating minute 12 of the hour and second 12 of the minute; a pair of electrodes  313  and  413  for indicating minute 13 of the hour and second 13 of the minute; a pair of electrodes  314  and  414  for indicating minute 14 of the hour and second 14 of the minute; a pair of electrodes  315  and  415  for indicating minute 15 of the hour and second 15 of the minute; a pair of electrodes  316  and  416  for indicating minute 16 of the hour and second 16 of the minute; a pair of electrodes  317  and  417  for indicating minute 17 of the hour and second 17 of the minute; a pair of electrodes  318  and  418  for indicating minute 18 of the hour and second 18 of the minute; a pair of electrodes  319  and  419  for indicating minute 19 of the hour and second 19 of the minute; and a pair of electrodes  330  and  430  for indicating minute 15 of the hour and second 15 of the minute. 
     Visible etching  23  frames electrode group  20  including 30 pairs of electrodes for indicating the minutes 31-59 respectively, and for indicating the seconds 31-60 respectively. For example, electrode group  20  includes a pair of electrodes  345  and  445  for indicating minute 45 of the hour and second 45 of the minute; a pair of electrodes  359  and  459  for indicating minute 59 of the hour and second 59 of the minute; and a pair of electrodes  360  and  460  for indicating second 60 of the minute. 
     Each of electrode groups  18  and  20  is on glass plate  12 . 
     AC-DC converter 29 supplies a DC power signal to time processing circuitry  36 . Time processing circuitry  36  is electrically coupled to each of electrodes  101  through  112 , and  121  through  132  via electrically conductive signal paths  24  in glass plate  12 . Time processing circuitry  36  is also electrically coupled to each of the electrodes in electrode group  18  via electrically conductive signal paths  24  in glass plate  12 . Time processing circuitry  36  is also electrically coupled to each of the electrodes in electrode group  20  via electrically conductive signal paths  24  in glass plate  12 . 
     FIG. 12 shows some of the electrodes in electrode group  18  in more detail, displaying the time 5:15 AM and 13 seconds (5:15:13). Each pair of electrodes includes an outer electrode surrounding an inner electrode. For example, outer electrode  415  surrounds inner electrode  315 . 
     FIG. 13 shows time processing circuitry  36  in more detail. Time processing circuitry  36  includes the features of circuitry  35  and also includes circuitry for driving the electrode pairs in electrode group  18  and electrode group  20 . Logic  53  includes minutes inputs  54 . Minutes inputs  54  include 60 inputs. Seconds inputs  55  includes 60 inputs. 
     Timer module  37 ′ maintains minutes register  46  with the current minute, in the range 1-59. Minute decode module  48  decodes the values of minutes register  46  and to address and write values into minutes latches  49 . Minutes latches  49  includes 59 latches for asserting voltages on 59 of minutes inputs  54  respectively. As shown in FIG. 13, the remaining minutes input  54  is always driven with a voltage indicating 0, because clock 2 never indicates minute 60. 
     Timer module  37 ′ maintains seconds register  50  with the current second, in the range 1-60. Second decodes module  51  decodes the values of seconds register  50  and to address and write values into seconds latches  52 . Seconds latches  52  includes 60 latches for asserting voltages on 60 of seconds inputs  55  respectively. 
     FIG. 14 shows logic  53  in more detail and emphasizes signal paths between logic  53  and the electrodes. Logic  53  may be conceptualized as 60 modules for driving the 60 electrode pairs constituting electrode groups  18  and  20 . Each module drives a respective electrode pair. For clarity, only 6 of the 60 modules are explicitly shown in FIG.  14 . 
     Each logic module has a respective input Mi from minute inputs  54 , and a respective input Si from seconds input  55 . For example, logic module  501  has an input M 1  from minutes inputs  54  and an input S 1  from seconds input  55 . Logic module  502  has an input M 2  from minutes inputs  54  and an input S 2  from seconds input  55 . Logic module  503  has an input M 3  from minutes inputs  54  and an input S 3  from seconds input  55 . Logic module  515  has an input M 15  from minutes inputs  54  and an input S 15  from seconds input  55 . Logic module  559  has an input M 59  from minutes inputs  54  and an input S 59  from seconds input  55 . Logic module  560  has an input M 60  from minutes inputs  54  and an input S 60  from seconds input  55 . 
     The functionality of minutes decode module  48  in the second embodiment of the invention is the same as the functionality in the first embodiment. The connectivity to the output of latches  49  is different than that of the first embodiment, however, because logic  53  is between latches  49  and electrodes. In step  20  for the second embodiment, if the value of MINUTE_POSITION is greater than the value in minutes register  46 , decode module  48  clears the latch driving the logic module (FIG. 14) for the electrode pair in the position indicated by MINUTE_POSITION. The logic modules may be designated module  500 +position, so that the module for minute position 1 is  501 , the module for minute position 2 is  502 , etc. Thus, in step  20  for the second embodiment, if the value of MINUTE_POSITION is greater than the value in minutes register  46 , decode module  48  clears the latch driving the minute input of logic module  500 +MINUTE POSITION. 
     In step  30  for the second embodiment, if MINUTE_POSITION is not greater than the value in minutes register  46 , decode module  48  writes a 1 into the latch driving the minute input of logic module  500 +MINUTE POSITION. (Step  30 ). 
     FIG. 15 expresses the functionality of second decode module  51 . Decode module  51  selects a first seconds position by setting a variable SECONDS_POSITION equal to 1 (Step  5 ). Decode module  51  compares the current value of SECONDS_POSITION to  60  (Step  10 ). If SECONDS_POSITION is less than or equal to 60, decode module  51  compares SECONDS_POSITION to the value in seconds register  50  (Step  15 ). 
     The logic modules may be designated module  500 +position, so that the module for minute position 1 is  501 , the module for minute position 2 is  502 , etc. Thus, in FIG. 15, if the value of SECONDS_POSITION is not equal to the value in seconds register  50 , decode module  51  clears the latch driving the seconds input of logic module  500 +SECONDS_POSITION. (step  20 ). 
     If SECONDS_POSITION is equal to the value in seconds register  50 , decode module  51  writes a 1 into the latch driving the seconds input of logic module  500 +SECONDS_POSITION. (Step  30 ). 
     Each logic module has an output Oi for driving the outer electrode of one of the electrode pairs, and an output Ii for driving the inner electrode of the respective electrode pair. For example, logic module  501  has an output O 1  for driving electrode  401 , and an output I 1  for driving electrode  301 . Logic module  502  has an output O 2  for driving electrode  402 , and an output I 2  for driving electrode  302 . Logic module  503  has an output O 3  for driving electrode  403 , and an output I 3  for driving electrode  303 . Logic module  515  has an output O 15  for driving electrode  415 , and an output  115  for driving electrode  315 . Logic module  559  has an output O 59  for driving electrode  459 , and an output  159  for driving electrode  359 . Logic module  560  has an output O 60  for driving electrode  460 . 
     The output O 15  of logic module  515 , as a function of inputs M 15  and S 15 , is described in Table 1 below. 
     
       
         
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                 M15 
                 S15 
                 O15 
               
               
                   
               
             
             
               
                 0 
                 0 
                 0 
               
               
                 0 
                 1 
                 1 
               
               
                 1 
                 0 
                 1 
               
               
                 1 
                 1 
                 1 
               
               
                   
               
             
          
         
       
     
     The output  115  of module  515 , as a function of inputs M 15  and S 15 , is described in Table 2 below. 
     
       
         
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                 M15 
                 S15 
                 I15 
               
               
                   
               
             
             
               
                 0 
                 0 
                 0 
               
               
                 0 
                 1 
                 0 
               
               
                 1 
                 0 
                 1 
               
               
                 1 
                 1 
                 0 
               
               
                   
               
             
          
         
       
     
     In general, the output Oi, as a function of the inputs Mi and Si, is described in Table 3 below. 
     
       
         
               
               
               
             
           
               
                 TABLE 3 
               
               
                   
               
               
                 Mi 
                 Si 
                 Oi 
               
               
                   
               
             
             
               
                 0 
                 0 
                 0 
               
               
                 0 
                 1 
                 1 
               
               
                 1 
                 0 
                 1 
               
               
                 1 
                 1 
                 1 
               
               
                   
               
             
          
         
       
     
     In general, the output Ii, as a function of the inputs Mi and Si, is shown in Table 4 below. 
     
       
         
               
               
               
             
           
               
                 TABLE 4 
               
               
                   
               
               
                 M15 
                 S15 
                 I15 
               
               
                   
               
             
             
               
                 0 
                 0 
                 0 
               
               
                 0 
                 1 
                 0 
               
               
                 1 
                 0 
                 1 
               
               
                 1 
                 1 
                 0 
               
               
                   
               
             
          
         
       
     
     FIG. 16 shows some of the electrodes in electrode group  18 , when clock  2  is displaying the time 5:15 AM and 14 seconds (5:15:14). 
     FIG. 17 shows some of the electrodes in electrode group  18 , when clock  2  is displaying the time 5:15 AM and 15 seconds (5:15:15). 
     FIG. 18 shows some of the electrodes in electrode group  18 , when clock  2  is displaying the time 5:15 AM and 16 seconds (5:15:16). 
     FIG. 19 shows some of the electrodes in electrode group  18 , when clock  2  is displaying the time 5:15 AM and 17 seconds (5:15:17). 
     In other words, each inner electrode is a type of display area for displaying minutes. Each outer electrode defines a rectangle. Each outer electrode is a type of display area for displaying seconds. Each outer electrode defines a rectangle completely overlapping a rectangle defined by an inner electrode. 
     Third Embodiment 
     FIG. 20 shows clock  2 ′ in accordance with a second, battery powered, embodiment of the present invention. Clock  2 ′ clock is similar to clock  2 , except the clock  2 ′ is powered by battery  32 , and that power conserving, time processing circuitry  36 ′ drives signal paths  24 . 
     FIG. 21 shows time processing circuitry  36 ′ in more detail. CPU  43  is normally in a low power sleep mode, except when the user sets the time using buttons (not shown) on clock  2 ′. Timing generator  47  applies a clock signal to logic-latches circuit  45 . Logic-latches circuit  45  is essentially a state machine implemented with custom hardwired circuitry. In response to a clock cycle from timing generator  47 , logic-latches circuit  45  changes one or more voltages going to electrodes  101 - 112 ,  121 - 132 , the outer electrodes, or the inner electrodes, to indicate the next increment in time. Time processing circuitry  36 ′ generates the identical signals as those generated by time processing circuitry  36  described above. 
     In summary, clock  1  includes 12 hour positions corresponding to electrodes  101 - 112 , for indicating the hours 1-12, respectively. Positions 1-6 define a right column, with position 1 at the top of the column and position 6 at the bottom of the column. Positions 7-12 define a left column, with position 7 at the bottom of the column and position 12 at the top of the column. The presence of a rectangle in an hour position indicates that the time is greater than or equal to that hour. For example, the presence of 3 rectangles, in positions 1-3, indicates that the time is at least 3:00. 
     The specific type of rectangle appearing in an hour position indicates whether the time is AM or PM. A hollow rectangle is the symbol for indicating AM and a solid block is the symbol for indicating PM. 
     Electrodes  101 - 106  are essentially a first display part defining a right vertical line. Electrodes  107 - 112  are essentially a second display part defining a left vertical line, parallel to the vertical line. 
     Hours decode module  42  acts to generate a signal to cause electrodes  101 - 106  to indicate time. Hours decode module  48  also acts to generate a signal to cause electrodes  107 - 112  to indicate time, such that a distance between electrode  101  and the most recently activated one of electrodes  107 - 112  is a decreasing function of the time. 
     Although the first and second embodiments of the invention employ discrete contiguous blocks arranged in columns, the invention is not so limited. 
     Although the first and second embodiments employ a liquid crystal display (LCD), the invention may be practiced with many different types of displays, including multi-color, light emitting display positions. 
     Although the exemplary embodiments employ discreet positions that make discreet transitions for each increment of time, the invention may be practiced with display positions that gradually change over time. 
     A pixel-based, portable computing device may be employed, such as a such as a Palm V™ Organizer, for example. The size and shape of display areas may change to indicate changes in time. 
     Additional advantages and modifications will readily occur to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or the scope of Applicants&#39; general inventive concept. The invention is defined in the following claims.