Abstract:
An instrument display that provides increased utility and flexibility by employing multiple range visual depictions. An instrument according to the present teachings includes an instrument display for providing a visual depiction of a set of physical phenomena wherein the visual depiction includes a trace for each physical phenomenon superimposed on a set of axes that provide multiple ranges.

Description:
BACKGROUND 
       [0001]    An instrument may include an instrument display for providing a visual depiction of how a physical phenomenon behaves with respect to a quantity of interest. For example, an oscilloscope may have a display for providing a visual depiction of how a magnitude of an electrical signal behaves with respect to time. 
         [0002]    A visual depiction of a physical phenomenon on an instrument display may include a trace superimposed on an axis that represents a range of a quantity of interest. For example, a visual depiction of an electrical signal on an oscilloscope display may include a trace that represents voltage values superimposed onto an x-axis that represents a range of time. 
         [0003]    A visual depiction of a physical phenomenon generated by a prior instrument may include only a single range. For example, a display for a prior oscilloscope may include one horizontal axis that represents a range of time onto which one or more traces may be superimposed. Unfortunately, prior instruments that provide a single range may be relatively limited in their ability to depict physical phenomena. 
       SUMMARY OF THE INVENTION 
       [0004]    An instrument display is disclosed that provides increased utility and flexibility by employing multiple range visual depictions. An instrument according to the present teachings includes an instrument display for providing a visual depiction of a set of physical phenomena wherein the visual depiction includes a trace for each physical phenomenon superimposed on a set of axes that provide multiple ranges. 
         [0005]    Other features and advantages of the present invention will be apparent from the detailed description that follows. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    The present invention is described with respect to particular exemplary embodiments thereof and reference is accordingly made to the drawings in which: 
           [0007]      FIG. 1  illustrates an instrument according the present teachings; 
           [0008]      FIGS. 2-4  show visual depictions rendered onto an instrument display according the present teachings. 
       
    
    
     DETAILED DESCRIPTION 
       [0009]      FIG. 1  illustrates an instrument  20  according the present teachings. The instrument  20  includes a display processor  10 , an instrument display  12 , and a user input subsystem  16 . The display processor  10  obtains a set of measurements  15  that pertain a set of physical phenomena and renders a visual depiction for the physical phenomena onto the instrument display  12  using multiple ranges of a quantity of interest, e.g. time. In one embodiment, the display processor  10  generates a visual depiction on the instrument display  12  in response to a set of display parameters  17  specified by a user via the user input subsystem  16 . 
         [0010]    The measurements  15  may include measurements generated locally in the instrument  20 , e.g. by one or more measurement channels (not shown) in the instrument  20 . The measurements  15  may include measurements generated by a remote instrument (not shown). The instrument  20  includes a network interface  18  for receiving measurements generated by a remote instrument. 
         [0011]    In one embodiment, the display processor  10  obtains the measurements  15  from a measurement buffer  14  in the instrument  20 . Each measurement  15  in the measurement buffer  14  may include a time-value pair that specifies, respectively, a time at which a corresponding measurement was obtained and a value for the corresponding measurement. For example, in an embodiment in which the instrument  20  is an oscilloscope, a time-value pair may includes a time value, e.g. a real-time value, and a voltage value. 
         [0012]    The measurement buffer  14  may hold measurement data for multiple variables, e.g. multiple measurement channels of the instrument  20  and measurement channels of remote instruments. For example, each time-value pair in the measurement buffer  14  may include a channel identifier. A channel identifier may specify a measurement channel of the instrument  20  for the corresponding time-value pair or a channel of another instrument connected via the network interface  18 . 
         [0013]    In another embodiment, the display processor  10  obtains the measurements  15  from one or more measurement channels in the instrument  20  or from the network interface  18  without passing the measurements  15  through a buffer. 
         [0014]    The user input subsystem  16  enables a user to enter the display parameters  17 . The display parameters  17  specify a set of ranges (range_ 1 , range_ 2 , . . . range_n) for a visual depiction to be generated on the instrument display  12 . A specified range may include a starting time and a resolution. A starting time may be a real-time value. A resolution may be specified in terms of seconds per division of an axis drawn on the instrument display  12 . 
         [0015]    In addition, the display parameters  17  specify a mapping of local and remote measurement channels to the ranges and a visual arrangement of ranges. A mapping may be specified using channel identifiers that include a combination of an instrument identifier and a channel number. 
         [0016]      FIG. 2  shows a visual depiction  100  rendered onto the instrument display  12  according the present teachings. The visual depiction  100  includes a pair of traces  130  and  132  superimposed on a pair of respective axis  120  and  122 . Each axis  120  and  122  includes an x component and a y component. The x component of each axis  120  and  122  represents time (t) and the y component of each axis  120  and  122  represents voltage magnitude (V). 
         [0017]    The display parameters  17  for the visual depiction  100  may be as follows. 
         [0018]    range_ 1 =start-time_A, resolution_A, 
         [0019]    instrument_A:channel_ 0 ; 
         [0020]    range_ 2 =start-time_B, resolution_B, 
         [0021]    instrument_A:channel_ 1 . 
         [0022]    The display processor  10  draws the range_ 1  as the axis  120  and the range_ 2  as the axis  122 . The display parameters  17  include a parameter that specifies a relative placement of the ranges, e.g. side by side as shown. The display processor  10  draws the trace  130  onto the axis  120  by obtaining measurement data for instrument_A:channel_ 0  from the measurement buffer  14 . In this example, the parameter “instrument_A” identifies the instrument  20 . The display processor  10  draws the trace  132  onto the axis  122  by obtaining measurement data for instrument_A:channel_ 1  from the measurement buffer  14 . The display processor  10  draws a trace by drawing points onto the appropriate axis in response to the time-value pairs and then drawing connections among the points. 
         [0023]    The start-time_A and resolution_A and start-time_B and resolution_B parameters provide a time scale for range_ 1  and a time scale for range_ 2 , respectively. For example, start-time_A and start-time_B may be real-time values and resolution_A may be 1 millisecond per division and resolution_B may be 1 microsecond per division. The trace  130  may precede the trace  132  in time, may follow the trace  132  in time, or may overlap in time with the trace  132 . 
         [0024]      FIG. 3  shows a visual depiction  200  rendered onto the instrument display  12  according the present teachings. The visual depiction  200  includes a pair of traces  230  and  232  superimposed on an axis  220  and a trace  234  superimposed on an axis  222 . The display parameters  17  for the visual depiction  200  may be as follows. 
         [0025]    range_ 1 =start-time_C, resolution_C, 
         [0026]    instrument_A:channel_ 0 ; 
         [0027]    range_ 1 =start-time_C, resolution_C, 
         [0028]    instrument_A:channel_ 1 ; 
         [0029]    range_ 2 =start-time_D, resolution_D, 
         [0030]    instrument_B:channel_ 0 . 
         [0031]    The display processor  10  draws the range_ 1  as the axis  220  and the range_ 2  as the axis  222 . The display parameters  17  may include a parameter that specifies a relative placement of the ranges, e.g. top to bottom as shown. The display processor  10  draws the traces  230  and  232  onto the axis  220  by obtaining measurement data for instrument_A:channel_ 0  and instrument_A:channel_ 1  from the measurement buffer  14 . The display processor  10  draws the trace  234  onto the axis  222  by obtaining measurement data for instrument_B:channel_ 0  from the measurement buffer  14  or directly via the network interface  18 . 
         [0032]    The axes  220  and  222  may have different resolutions. The axes  220  and  222  may have the same or different start times. The trace  234  may precede the traces  230  and  232  in time, may follow the traces  230  and  232  in time, or may overlap in time with the traces  230  and  232 . 
         [0033]      FIG. 4  shows a visual depiction  300  rendered onto the instrument display  12  according the present teachings. The visual depiction  300  includes a pair of traces  330  and  332  superimposed on an axis  320 . The x component of the axis  320  has a discontinuity  322  in time between a section  324  and a section  326 . The display parameters  17  for the visual depiction  100  may be as follows. 
         [0034]    range_ 1 =start-time_E, resolution_E, 
         [0035]    instrument_A:channel_ 0 ; 
         [0036]    range_ 1 =start-time_F, resolution_F, 
         [0037]    instrument_A:channel_ 0 . 
         [0038]    The parameters start-time_E and resolution_E specify a time scale for the section  324  and the parameters start-time_F and resolution_F specify a time scale for the section  326 . The display processor  10  draws the range_ 1  as the axis  320  including the sections  324  and  326  having the specified starting times and resolutions. The display processor  10  draws the traces  330  and  332  onto the axis  320  by obtaining measurement data for instrument_A:channel_ 0  from the measurement buffer  14 . The display processor  10  uses the time values of the time-value pairs obtained from the measurement buffer  14  to map the measurement data points to the appropriate section  324  and  326 . The sections  324  and  326  may have the same or different time resolutions. The visual depiction  300  may be particularly applicable in applications in which the time span between the start-time_E and the start-time_F is relatively large but the data of interest in the traces  330  or  332  is relatively brief. The view of the traces  330  and  332  may be expanded using appropriate selections for the resolution_E and the resolution_F. 
         [0039]    The instrument  20  may include multiple displays for providing visual depictions according to the present techniques. The instrument  20  may export visual depictions to an external device via the network interface  18 . For example, the instrument  20  may export visual depictions to another instrument or to a personal computer. 
         [0040]    A visual depiction according to the present techniques may be partitioned vertically or horizontally. For example, a visual depiction may include a 2 by 2 array of axes or any other arrangement. In another example, one wide range axis may be stacked over two or more narrower range axes, or vice versa. 
         [0041]    The traces in a visual depiction according to the present teachings may be triggered by an input signal sampled locally by the instrument  20  or may be triggered by a message received via the network interface  18  or may be triggered by a local real-time clock in the instrument  20 . A trigger may be in the present or in the future. For example, if an experiment is to start at a known time then the traces may be triggered at that known time whether or not any signal of interest have occurred. Similarly, a trigger may be in the past and the traces drawn after the fact given that the measurements  15  are associated with time-stamps. Triggering on an event detected by a remote instrument using a network message may be applicable in systems in which the remote instrument is the only instrument capable of detecting the event. Triggering on a real-time (time-of-day) may be used to start traces even if the instrument  20  is not connected to a triggering event. This may be useful when it is desirable to show measurement values in relation to trigger time. Triggering in the past may be useful for showing measurements obtained by remote instruments or simulated measurements or measurements stored in a database as a function of real-time even when the measurements are not available in real-time. 
         [0042]    The time axes in a visual depiction according to the present techniques are labeled so that an operator of the instrument  20  may know the time ranges for the various traces. For example, the starting times for a discontinuity are labeled. The time axes may be labeled with an absolute time when appropriate to an application. 
         [0043]    A visual depiction according to the present techniques enables comparison of measurements obtained by multiple instruments. For example, traces from measurements generated by different instruments may be placed side-by-side and compared using a “marker” functions, e.g. a marker function of an oscilloscope. Marker A may be placed on an interesting point on a first trace and marker B placed on an interesting point of a second trace so that the instrument  20  shows the time in between. 
         [0044]    A visual depiction according to the present techniques enables built in functions of the instrument  20  to be applied to measurements obtained by other instruments. For example, an RMS or rise-time measurement function of the instrument  20  may be applied to a trace that represents measurements received from a remote instrument. 
         [0045]    A visual depiction according to the present techniques enables a view of one trace having a relatively large range next to a view of one or more other traces having relatively short but expanded ranges, i.e. traces that zoom-in in terms of time. This provides an operator of the instrument  20  with a view of intervals between events as well as a detailed view of events themselves. 
         [0046]    The instrument  20  may include a marker function that provides a pair of markers for each trace. This allows an operator to explore a variety of relationships among traces without cluttering the instrument display  12 . This may be particularly useful for a visual depiction having two ranges with that cover the same time span. For example, if events A, B, C, and D occur in sequence then two markers may be used on one range for A-C and two markers on another range for B-D. 
         [0047]    The above embodiments show visual depictions having multiple ranges of time. Visual depictions according to the present techniques may be used to provides multiple ranges of any quantity. For example, the instrument  20  may be embodied as a spectrum analyzer that generates a visual depiction having multiple frequency-ranges. In another example, the instrument  20  may be embodied as a surface-roughness gauge which shows distance from the edge on the x-axis and the height of the surface on the y-axis. 
         [0048]    In some embodiments, a range may be specified in terms of a starting time and an ending time or a starting time and a duration. In addition, the display parameters  17  may specify an allocation of axes to the viewable area of the instrument display  12 . For example, the display parameters  17  may indicate that range_ 1  gets 75 percent of the display area and range_ 2  gets 25 percent of the display area. 
         [0049]    The foregoing detailed description of the present invention is provided for the purposes of illustration and is not intended to be exhaustive or to limit the invention to the precise embodiment disclosed. Accordingly, the scope of the present invention is defined by the appended claims.