Waveform display device and waveform display method

Abstract

To provide a waveform display device and a waveform display method capable of easily and quickly locating cursor display in a signal waveform at a desired position.SOLUTION: A waveform display device executes scroll display processing which performs scrolling in a scroll moving amount relatively scrolling at least one of a signal waveform and cursor display against the other on the basis of a resistance value of a first slide variable resistor 31a to which a first resistance value to be specific reference is set, and display magnification change processing which displays to a waveform display screen by enlarging or contracting display magnification of the signal waveform in a time axis direction on the basis of a resistance value of a second slide variable resistor 32a to which a second resistance value to be a specific reference is set. A moving amount of scroll and a moving direction are set by a difference between the first resistance value and the resistance value of the first slide variable resistor 31a, and display magnification of the signal waveform is set by a difference between the second resistance value and the resistance value of the second slide variable resistor 32a, and is enlarged or contracted to display the signal waveform to the waveform display screen.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a waveform display device and a waveform display method for displaying a signal waveform on a waveform display screen. [Background technology]

[0002] Conventionally, a waveform display device and a waveform display method are disclosed in Patent Document 1 below as a device for displaying measurement data as a waveform (hereinafter, the technology disclosed in Patent Document 1 will be referred to as the "Publication 1 Invention"). This waveform display device has a measurement section, an operation section, a display section, a control section and a memory section, and stores measurement data measured by the measurement section in the memory section. The control section generates the measurement data as display data, and then displays both the signal waveform and the cursor of the display data on the waveform display screen of the display section. In this state, when a switch operation is performed on the operation section, the control section displays an enlarged waveform display screen superimposed on a portion of the signal waveform, and displays the signal waveform and the enlarged signal waveform on the enlarged waveform display screen so that they overlap at the display position of the displayed cursor. While maintaining this state, at least one of the signal waveform and the enlarged signal waveform or the cursor display in the enlarged waveform display screen is scrolled relative to the other to the desired position, making it possible to display the signal waveform. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-10036 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the invention disclosed in the document 1 has the following problems. Conventional waveform display devices and waveform display methods employ a configuration in which, when a predetermined switch operation is performed while a signal waveform at a relatively low display magnification (hereinafter, the signal waveform at a relatively low display magnification will be referred to as "signal waveform A") is displayed on a waveform display screen together with a cursor display, a point designated by the cursor display and a point on a signal waveform on an enlarged waveform display screen displayed as part of signal waveform A (hereinafter, the signal waveform on the enlarged waveform display screen will be referred to as "enlarged signal waveform B") are displayed so as to overlap at their display positions. In this case, a scroll operation is generally performed to move the cursor display closer to a desired position while referring to signal waveform A displayed on the waveform display screen, and then a scroll operation is generally performed to position the cursor display at a desired position while referring to enlarged signal waveform B displayed on the enlarged waveform display screen.

[0005] However, for example, when signal waveform A and enlarged signal waveform B are displayed, the enlarged waveform display range of enlarged signal waveform B may not be appropriate. In such a case, it is necessary to reset the enlarged waveform display magnification or the time axis range for displaying the enlarged waveform via a separate setting screen, etc., display an appropriate enlarged signal waveform B, perform a scroll operation, and move the cursor display to a desired position.

[0006] On the other hand, when the time axis of signal waveform A to be partially enlarged and displayed is specified and enlarged signal waveform B is displayed on the enlarged waveform display screen at a high display magnification to make it easier to visually identify the peculiar waveform portion, the peculiar waveform portion may not be displayed on the enlarged waveform display screen due to the narrow range of the time axis of enlarged signal waveform B that can be displayed on the enlarged waveform display screen. In this case, the cursor display is moved in advance to the vicinity of the peculiar waveform portion by scrolling, and the operation is repeated to display the partial enlarged display. However, if the peculiar waveform portion cannot be visually identified when signal waveform A is displayed in the first place, it is necessary to enlarge signal waveform A until the peculiar waveform portion can be visually identified.

[0007] In this way, in the invention disclosed in the prior art 1, when specifying a portion of the signal waveform to be enlarged and displayed, it is necessary to repeatedly perform a scroll operation to position the cursor display at the desired position, which makes the operation complicated, and it is desirable to improve this.

[0008] The present invention has been made in consideration of the above problems, and has as its main object to provide a waveform display device and a waveform display method that can easily and quickly position a cursor display on a signal waveform to a desired position. [Means for solving the problem]

[0009] In order to achieve the above object, a waveform display device according to the present invention displays a signal waveform based on waveform data on a waveform display screen, and displays a cursor display for designating an arbitrary point on the signal waveform on the waveform display screen superimposed on the signal waveform, and also includes a scroll display process for setting a scroll movement amount for scrolling at least one of the signal waveform and the cursor display relative to the other based on a resistance value of a first slide variable resistor to which a specific reference first resistance value is set, and scrolling the signal waveform by setting a display magnification of the signal waveform based on a resistance value of a second slide variable resistor to which a specific reference second resistance value is set, and enlarging or reducing the signal waveform in the time axis direction to display the signal waveform on the waveform display screen. and a display magnification changing process for changing the display magnification of the signal waveform displayed on the waveform display screen, wherein when the first slide variable resistor is operated while both the signal waveform and the cursor display are displayed on the waveform display screen, the processing unit sets an amount and direction of movement for scrolling at least one of the signal waveform and the cursor display relative to the other based on a difference between the first resistance value and a resistance value of the first slide variable resistor, and when the second slide variable resistor is operated, sets the display magnification of the signal waveform based on a difference between the second resistance value and a resistance value of the second slide variable resistor, and enlarges or reduces the signal waveform to be displayed on the waveform display screen. Furthermore, in the waveform display device of the present invention, the display magnification change process sets the display magnification of the signal waveform based on a time axis that corresponds to the display position of the cursor display by the difference between the second resistance value and the resistance value of the second slide variable resistor when the second slide variable resistor is operated, and enlarges or reduces the signal waveform to be displayed on the waveform display screen. Furthermore, the waveform display device of the present invention is switchable between the scroll display process and the display magnification change process, and includes a processing unit that executes the scroll display process of setting the scroll movement amount and scrolling based on the resistance value of a third slide variable resistor to which a specific reference third resistance value is set, or the display magnification change process of setting the display magnification of the signal waveform and enlarging or reducing it in the time axis direction to display it on the waveform display screen, and when the processing unit switches to the scroll display process or the display magnification change process while both the signal waveform and the cursor display are displayed on the waveform display screen and the third slide variable resistor is operated, the processing unit performs the scroll display process or the display magnification change process based on the difference between the third resistance value and the resistance value of the third slide variable resistor, and displays the signal waveform on the waveform display screen. In addition, in the waveform display device of the present invention, the slider of the first slide variable resistor, the slider of the second slide variable resistor and / or the slider of the third slide variable resistor are insulated from the internal circuitry of the waveform display device. Furthermore, in the waveform display device according to the present invention, the first slide variable resistor, the second slide variable resistor and / or the third slide variable resistor are self-resetting. Furthermore, a waveform display method according to the present invention includes a scroll display process for displaying a signal waveform based on waveform data on a waveform display screen, and displaying a cursor display for designating an arbitrary point on the signal waveform on the waveform display screen so as to be superimposed on the signal waveform, and setting a scroll movement amount for scrolling at least one of the signal waveform and the cursor display relative to the other based on a resistance value of a first slide variable resistor to which a specific reference first resistance value is set, and scrolling the signal waveform by setting a display magnification of the signal waveform based on a resistance value of a second slide variable resistor to which a specific reference second resistance value is set, and enlarging or reducing the signal waveform in the time axis direction. and a display magnification change process for displaying the signal waveform on a display screen, wherein when the first slide variable resistor is operated while both the signal waveform and the cursor display are displayed on the waveform display screen, a movement amount and a movement direction for scrolling at least one of the signal waveform and the cursor display relative to the other are set based on the difference between the first resistance value and the resistance value of the first slide variable resistor, and when the second slide variable resistor is operated, the display magnification of the signal waveform is set based on the difference between the second resistance value and the resistance value of the second slide variable resistor, and the signal waveform is enlarged or reduced and displayed on the waveform display screen. Effect of the Invention

[0010] In the waveform display device and waveform display method of the present invention, when the first slide variable resistor is operated while both a signal waveform and a cursor are displayed on the waveform display screen, a scroll process is executed to scroll at least one of the signal waveform and the cursor display relative to the other based on the difference between a specific reference first resistance value and the resistance value of the first slide variable resistor, and when the second slide variable resistor is operated, a display magnification change process is executed to change the display magnification of the signal waveform based on the difference between a specific reference second resistance value and the resistance value of the second slide variable resistor, and the signal waveform and the cursor are displayed on the waveform display screen.

[0011] As an example, when the resistance value of the first sliding variable resistor is greater than the first resistance value, the cursor display is scrolled to the left on the waveform display screen, the signal waveform is scrolled to the right on the waveform display screen, or both are performed; when the resistance value of the first sliding variable resistor is smaller than the first resistance value, the cursor display is scrolled to the right on the waveform display screen, the signal waveform is scrolled to the left on the waveform display screen, or both are performed, with the amount (speed) of scrolling being set according to the difference between the first resistance value and the resistance value of the first sliding variable resistor.

[0012] In addition, when the resistance value of the second slide variable resistor is greater than the second resistance value, the display magnification of the signal waveform is increased and the waveform display is enlarged in the time axis direction, and when the resistance value of the second slide variable resistor is smaller than the second resistance value, the display magnification of the signal waveform is decreased and the waveform display is reduced in the time axis direction, and the magnitude of the display magnification for enlargement or reduction is set according to the difference between the second resistance value and the resistance value of the second slide variable resistor.

[0013] Therefore, with the waveform display device and waveform display method of the present invention, while referring to the signal waveform displayed on the waveform display screen, and without the need for a relatively expensive pointing device (such as a mouse, touch pad or touch panel), a simple operation of simply sliding the inexpensive first and second slide variable resistors allows the user to scroll the cursor display closer to the desired position while simultaneously enlarging or reducing the signal waveform. Even a user who is unfamiliar with operating this type of device can accurately, easily and quickly position the cursor display to the desired position, and since the signal waveform displayed at an appropriate display magnification can be referred to, level changes in the input signal on which the waveform data is based can be easily observed.

[0014] Furthermore, according to the waveform display device of the present invention, when the second slide variable resistor is operated, if the resistance value of the second slide variable resistor is greater than the second resistance value, the display magnification of the signal waveform is increased based on the time axis associated with the cursor display position on the waveform display screen, and the waveform display is enlarged in the time axis direction, and if the resistance value of the second slide variable resistor is smaller than the second resistance value, the display magnification of the signal waveform is decreased based on the time axis associated with the cursor display position on the waveform display screen, and the waveform display is reduced in the time axis direction, and the magnitude of the display magnification for enlargement or reduction is set according to the difference between the second resistance value and the resistance value of the second slide variable resistor. Therefore, according to the waveform display device of the present invention, the center position when enlarging or reducing the display of a signal waveform can be set arbitrarily and then fixed, with the result that the user will not lose track of the position of the cursor display when changing the display magnification.

[0015] Furthermore, according to the waveform display device of the present invention, the functions of the first and second slide variable resistors are combined into a single third slide variable resistor, which can be switched depending on the scrolling process and the display magnification change process. This makes it possible to configure a cheaper and smaller operating unit than a configuration using two slide variable resistors, and therefore the device can be easily adopted even in measuring instruments with a relatively small body shape, such as handheld measuring instruments.

[0016] Furthermore, in the waveform display device according to the present invention, the operation parts of the first to third slide variable resistors are insulated from the internal circuit of the waveform display device, so that, for example, in a measuring device that complies with CAT III 600V of the European Low Voltage Directive EN61010-1, which specifies the insulation performance of the measuring device and the measurement points of the power distribution equipment to which the measuring device can be connected, a withstand voltage test voltage of about 6300V is used to test whether the insulation is properly performed between the measurement terminals (internal circuit) and the exterior that the user can directly touch. In this case, it is very difficult to maintain a good insulating state with a measuring device that uses a pointing device, but with a structure that uses only the slide variable resistor as the operation part, a good insulating state can be easily maintained by forming the slider of the slide variable resistor from an insulating material. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a diagram showing the configuration of a waveform display device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a configuration diagram showing the configuration of an operation unit in a waveform display device according to an embodiment of the present invention. [Diagram 3] FIG. 3 is a configuration diagram showing the configuration of another operation unit in the waveform display device according to the embodiment of the present invention. [Figure 4] FIG. 4 is a display screen diagram showing a state in which a cursor displayed superimposed on a signal waveform on a waveform display screen in the waveform display device according to the embodiment of the present invention is scrolled to the left or right as indicated by an arrow. [Diagram 5] FIG. 5 is a diagram showing a display screen of a signal waveform displayed superimposed on a cursor on a waveform display screen in a waveform display device according to an embodiment of the present invention. [Figure 6] FIG. 6 is a display screen diagram showing a state in which a signal waveform displayed superimposed on a cursor on the waveform display screen has been scrolled to the right as indicated by an arrow in the waveform display device according to the embodiment of the present invention. [Figure 7]FIG. 7 is a display screen diagram showing a waveform display device according to an embodiment of the present invention in which a cursor displayed on a waveform display screen is scrolled to the left or right as indicated by the arrow, while at the same time the signal waveform is scrolled in the direction opposite to the scrolling direction of the cursor. [Figure 8] FIG. 8 is a diagram showing a display screen in a waveform display device according to an embodiment of the present invention, in which the cursor has reached the limit of the left scrollable range of the waveform display screen, causing only the signal waveform to be scrolled to the right as indicated by the arrow. [Figure 9] FIG. 9 is a diagram showing a display screen in which the cursor has reached the limit of the rightward scrollable range of the waveform display screen in a waveform display device according to an embodiment of the present invention, and only the signal waveform has been scrolled to the left as indicated by the arrow. [Figure 10] FIG. 10 is a display screen diagram showing a state in which the signal waveform of the measurement data displayed at the center of the time axis of the waveform display screen is fixed and displayed in a fixed size along the time axis in a waveform display screen according to an embodiment of the present invention. [Figure 11] FIG. 11 is a display screen diagram showing a state in which the signal waveform of the measurement data displayed at the center of the time axis of the waveform display screen is fixed and displayed in a fixed state, while the signal waveform is displayed twice as large in the time axis direction in a waveform display screen of an embodiment of the present invention. [Figure 12] FIG. 12 is a display screen diagram showing a state in which the signal waveform of the measurement data displayed at the center of the time axis of the waveform display screen is fixed and displayed in a quadruple manner along the time axis in a waveform display device according to an embodiment of the present invention. [Figure 13] FIG. 13 is a display screen diagram showing a waveform display device according to an embodiment of the present invention in which a cursor is fixed on the waveform display screen and the signal waveform is displayed at 1x magnification in the time axis direction, with the measurement data corresponding to that display position used as the reference. [Figure 14]FIG. 14 is a display screen diagram showing a waveform display device according to an embodiment of the present invention in which a cursor is fixed on the waveform display screen and the signal waveform is displayed twice as large in the time axis direction, based on the measurement data corresponding to the display position. [Figure 15] FIG. 15 is a display screen diagram showing a waveform display device according to an embodiment of the present invention in which a cursor is fixed on the waveform display screen and the signal waveform is displayed four times larger in the time axis direction, based on the measurement data corresponding to the display position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] A waveform display device and a waveform display method according to an embodiment of the present invention will now be described with reference to the accompanying drawings.

[0019] The waveform display device 1 shown in Figure 1 comprises a measurement section 2, an operation section 3, a display section 4, a control section 5 and a memory section 6, and is configured to be able to display a signal waveform W (see Figure 4) on the display section 4 in accordance with a waveform display method which will be described later.

[0020] The measurement unit 2, under the control of the control unit 5, measures a predetermined physical quantity (input signal Sig, for example electrical parameters such as current value and voltage value) to generate measurement data Dn (n is a sampling number), and outputs the generated measurement data Dn to the control unit 5.

[0021] The operation unit 3 shown in FIG. 2 includes a process changeover switch 35 for changing over the operating conditions of the waveform display device 1, a first slide variable resistor 31a having a slider 31b, an ADC 33 for converting a control voltage RA1 output from the first slide variable resistor 31a into a digital signal, a second slide variable resistor 32a having a slider 32b, and an ADC 34 for converting a control voltage RA2 output from the second slide variable resistor 32a into a digital signal, and outputs the digital signals RD1, 2 output from the ADCs 33, 34 and a process changeover signal ST1 from the process changeover switch 35 to the control unit 5.

[0022] Alternatively, as shown in FIG. 3, the operation unit 3′ includes a process changeover switch 38 for changing over the operating conditions of the waveform display device 1, a third slide variable resistor 36a having a slider 36b, and an ADC 37 for converting a control voltage RA3 output from the third slide variable resistor 36a into a digital signal, and outputs a digital signal RD3 from the ADC 37 and a process changeover signal ST2 from the process changeover switch 38 to the control unit 5.

[0023] As an example, the total resistance value of each of the slide variable resistors 31a, 32a, 36a is set to 20 kΩ. When each slider 31b, 32b, 36b is positioned at the center of the slider movement range of each of the slide variable resistors 31a, 32a, 36a, the resistance values ​​from each slider 31b, 32b, 36b to one end and the other end of each of the slide variable resistors 31a, 32a, 36a become the first, second and third resistance values ​​of 10 kΩ which are specific reference values. One end of the total resistance terminal is connected to a circuit voltage of 3.3 V and the other end is connected to 0 V (GND). An ADC33 is connected to the slider 31b, an ADC34 is connected to the slider 32b, and an ADC37 is connected to the slider 36b.

[0024] When the sliders 31b, 32b, 36b of the slide variable resistors 31a, 32a, 36a are positioned directly at one end, the control voltages RA1, 2, 3 are 3.3 V (=3.3 V×20 kΩ (resistance value between each slider 31b, 32b, 36b and the other end) / 20 kΩ), when positioned at the center of the movement range, 1.65 V (=3.3 V×10 kΩ / 20 kΩ), and when positioned directly at the other end, 0 V (=3.3 V×0 Ω (resistance value between each slider 31b, 32b, 36b and the other end) / 20 kΩ). The control voltages RA1, 2, 3 change linearly in accordance with the movement position of the sliders 31b, 32b, 36b and are applied to the ADCs 33, 34, 37.

[0025] Each of the slide variable resistors 31a, 32a, 36a can self-return. That is, each of the slide variable resistors 31a, 32a, 36a has an elastic member such as a coil spring built therein, and this elastic member is connected to each of the sliders 31b, 32b, 36b. Therefore, when the sliders 31b, 32b, 36b are operated to move from their initial positions and then released from the external force at that position, each of the sliders 31b, 32b, 36b automatically returns to its initial position by elastic force (restoring force).

[0026] Each of the ADCs 33, 34, and 37 is, for example, configured using an ADC (analog / digital converter) with a power supply voltage of 3.3 V and a 10-bit resolution, and converts each of the digital signals RD1, 2, and 3 corresponding to each of the control voltages RA1, 2, and 3 into the following with a resolution of approximately 3.222 mV / count (=3.3÷1024 (2 to the power of 10)). RD=RA÷3.222mV...[Formula 1] Specifically, If RA is 3.3V, then 1024 counts = 3.3 x 1000 ÷ 3.222 If RA is 1.65V, then 512 counts = 1.65 x 1000 ÷ 3.222 If RA is 0.0V, 0 counts = 0.0 x 1000 ÷ 3.222 The digital signals RD1, RD2, and RD3 which change linearly in accordance with the control voltages RA1, RA2, and RA3 are generated and output to the control unit 5.

[0027] The process changeover switch 35 or the process changeover switch 38 outputs to the control unit 5 a process changeover signal ST1 or ST2 for switching the control method between each scroll process and each display magnification change process.

[0028] The display unit 4 shown in FIG. 4 is configured, as an example, with an LCD display of XGA (resolution: 1024 pixels x 768 pixels) standard, and displays a signal waveform W and a cursor 42a on a waveform display screen 41 based on display data output from the control unit 5.

[0029] The control unit 5 corresponds to a "processing unit" and controls the waveform display device 1 in an overall manner. Specifically, the control unit 5 controls the measurement unit 2 in response to the digital signal RD1, 2 or RD3 from the operation unit 3, and causes the measurement unit 2 to execute a measurement process of the input signal Sig (a process of generating measurement data Dn of the input signal Sig). The control unit 5 also stores the measurement data Dn output from the measurement unit 2 in the storage unit 6, and generates display data of the signal waveform W based on the measurement data Dn, outputs it to the display unit 4, and causes the signal waveform W to be displayed on the waveform display screen 41. The control unit 5 also displays a cursor 42 for designating an arbitrary point on the signal waveform W displayed on the waveform display screen 41, superimposed on the signal waveform W, on the waveform display screen 41.

[0030] Furthermore, when a scroll operation, which will be described later, is performed while the signal waveform W and the cursor 42 are displayed on the waveform display screen 41 of the display unit 4, the control unit 5 executes a scroll display process for scrolling the signal waveform W and / or the cursor 42 in the time axis direction. Specifically, for example, when the waveform display screen 41 is displayed on the display unit 4 as shown in Fig. 4, when a scroll operation is performed, depending on the content of the operation, a cursor scroll display process (one example of a "scroll display process") for scrolling only the cursor 42 in the time axis direction (in this example, the directions of the left arrow and right arrow shown in Fig. 4) is executed, a waveform scroll display process (another example of a "scroll display process") for scrolling only the signal waveform W in the time axis direction as shown in Figs. 5 and 6, and a waveform cursor scroll display process (yet another example of a "scroll display process") for scrolling both the signal waveform W and the cursor 42 in the time axis direction as shown in Figs. 7 to 9 are executed.

[0031] In addition, when the signal waveform W and cursor 42 are displayed on the waveform display screen 41 of the display unit 4 and a zoom operation described below is performed, the control unit 5 executes a screen-based display magnification change process (one example of a "display magnification change process") in which the signal waveform W is enlarged or reduced in the time axis direction while the measurement data Dn displayed at the center of the time axis of the waveform display screen 41 is fixed as shown in Figures 10 to 12, or a cursor display position-based display magnification change process (another example of a "display magnification change process") in which the signal waveform W is enlarged or reduced in the time axis direction based on the measurement data Dn corresponding to the display position while the cursor 42 is fixed on an arbitrary time axis of the waveform display screen 41 as shown in Figures 13 to 15 (a state in which the display position of the cursor 42 on the waveform display screen 41 does not change when the display magnification is changed).

[0032] In addition, when the operating conditions of the waveform display device 1 are switched and a scroll operation or a zoom operation described below is performed while the signal waveform W and cursor 42 are displayed on the waveform display screen 41 of the display unit 4, the control unit 5 executes cursor scroll display processing, waveform scroll display processing, waveform cursor scroll display processing, screen-based display magnification change processing, or cursor display position-based display magnification change processing.

[0033] The storage unit 6 stores the operation program of the control unit 5, the measurement data Dn, etc. The storage unit 6 is configured with, for example, a RAM, a magnetic disk, an optical disk, etc., and also includes recording media such as an SD card, a USB memory, an SSD, an HDD, a CD, and a Blu-ray (registered trademark).

[0034] Next, the process and method of displaying the signal waveform W and the cursor by the waveform display device 1 will be described with reference to the attached drawings.

[0035] In this waveform display device 1, as an example, when a measurement start switch (not shown) of the operation unit 3 is operated, the control unit 5 controls the measurement unit 2 in accordance with preset measurement conditions to cause the measurement unit 2 to start a measurement process. At this time, the measurement unit 2 digitally converts each input signal Sig to generate measurement data Dn, and outputs the generated measurement data Dn to the control unit 5. In response to this, the control unit 5 sequentially stores the measurement data Dn output from the measurement unit 2 in the storage unit 6. Also, when a measurement end switch (not shown) of the operation unit 3 is operated, the control unit 5 controls the measurement unit 2 to cause the measurement unit 2 to end the measurement process. As a result, the measurement data Dn for a predetermined time generated by the measurement unit 2 is stored in the storage unit 6. In addition, in this waveform display device 1, the signal waveform W based on the measurement data Dn can also be displayed on the display unit 4 in parallel with the above-mentioned measurement process. However, to facilitate understanding of the "scroll display process" and "display magnification change process," the following describes the process of displaying the signal waveform W and cursor 42 on the display unit 4 based on the measurement data Dn stored in the memory unit 6.

[0036] Specifically, when a predetermined time's worth of measurement data Dn is stored in the memory unit 6 and an operation is performed to display the waveform display screen 41, the control unit 5 reads out the measurement data Dn from the memory unit 6, and, as an example, displays a signal waveform W and a cursor 42a at a predefined display magnification based on the measurement data Dn on the waveform display screen 41 as shown in Fig. 4. The signal waveform W and cursor 42a can be scrolled by moving the slider 31b of the first sliding variable resistor 31a of the operation unit 3 shown in Fig. 2, thereby arbitrarily moving the display position of the signal waveform W and / or the cursor 42a on the waveform display screen 41.

[0037] In the cursor scroll display process, the process changeover switch 35 of the operation unit 3 is operated to output a process changeover signal ST1 to the control unit 5. When the cursor scroll display process is selected, for example, a control voltage RA1 corresponding to the resistance value at the position of the slider 31b is output from the first slide variable resistor 31a arranged in the operation unit 3 to the ADC 33, and a digital signal RD1 corresponding to the control voltage RA1 is output from the ADC 33 to the control unit 5.

[0038] In the control unit 5, as an example, the digital signal RD1 when the slider 31b is located at the center of the slider movement range of the first sliding variable resistor 31a is stored in the storage unit 6 as a reference digital value RD1m for stopping the cursor scroll display process, and the digital value RD1m and the digital signal RD1 are always compared and calculated to set the scroll movement amount of the cursor 42a according to the difference between an arbitrary digital signal RD1 that changes linearly from the digital value RD1m. At the same time, the movement direction of the cursor 42a according to the difference between the digital value RD1m and the arbitrary digital signal RD1 is set, and when the digital signal RD1 exceeds the digital value RD1m, the cursor 42a on the waveform display screen 41 is scrolled in the direction of the left arrow on the time axis. Also, when the digital signal RD1 is less than the digital value RD1m, the cursor 42a on the waveform display screen 41 is scrolled in the direction of the right arrow on the time axis.

[0039] In the waveform scrolling display process, the process switching switch 35 of the operation unit 3 is operated to output a process switching signal ST1 to the control unit 5, and when the waveform scrolling display process is selected, for example, a digital signal RD1 is output to the control unit 5 in a configuration similar to that of the cursor scrolling display process described above.

[0040] The control unit 5 similarly stores the digital value RD1m in the storage unit 6 as a reference value for stopping the waveform scrolling display process, constantly compares the digital value RD1m with the digital signal RD1, and sets the scroll movement amount of the signal waveform W according to the difference between an arbitrary digital signal RD1 that changes linearly from the digital value RD1m. At the same time, it sets the movement direction of the signal waveform W according to the difference between the digital value RD1m and the arbitrary digital signal RD1, and when the digital signal RD1 exceeds the digital value RD1m, it scrolls the signal waveform W on the waveform display screen 41 in the direction of the right arrow on the time axis. Also, when the digital signal RD1 is less than the digital value RD1m, it scrolls the signal waveform W on the waveform display screen 41 in the direction of the left arrow on the time axis.

[0041] In addition, in the waveform cursor scroll display process, the process changeover switch 35 of the operation unit 3 is operated to output a process changeover signal ST1 to the control unit 5, and when the waveform cursor scroll display process is selected, for example, a digital signal RD1 is output to the control unit 5 in a configuration similar to that of the above-mentioned cursor scroll display process.

[0042] The control unit 5 similarly stores the digital value RD1m in the storage unit 6 as a reference value for stopping the waveform cursor scroll display process, constantly compares the digital value RD1m with the digital signal RD1, and sets the scroll movement amount of the cursor 42a and the signal waveform W according to the difference between an arbitrary digital signal RD1 that changes linearly from the digital value RD1m. At the same time, it sets the movement direction of the signal waveform W and the cursor 42a according to the difference between the digital value RD1m and the arbitrary digital signal RD1, and when the digital signal RD1 exceeds the digital value RD1m, it scrolls the cursor 42a on the waveform display screen 41 in the left arrow direction on the time axis, and when the cursor 42a reaches, for example, the cursor 42b at the left end of the waveform display screen 41, it scrolls the signal waveform W in the opposite direction to the scroll direction of the cursor 42a (the right arrow direction on the time axis). Furthermore, when the digital signal RD1 is less than the digital value RD1m, the cursor 42a on the waveform display screen 41 is scrolled in the direction of the right arrow on the time axis, and when the cursor 42a reaches, for example, the cursor 42c at the right end of the waveform display screen 41, the signal waveform W is scrolled in the opposite direction to the scrolling direction of the cursor 42a (the direction of the left arrow on the time axis). Note that the scrollable range of the cursor 42a is arbitrary within the range of the time axis of the waveform display screen 41, so the position before the left end of the waveform display screen 41 (i.e., between the cursors 42a and 42b) may be set as the left end of the scrollable range of the cursor 42a, and the position before the right end of the waveform display screen 41 (i.e., between the cursors 42a and 42c) may be set as the right end of the scrollable range of the cursor 42a.

[0043] The operation of enlarging or reducing the signal waveform W can be performed by moving the slider 32b of the second sliding variable resistor 32a of the operation unit 3 shown in Figure 2, thereby enlarging or reducing the signal waveform W in the time axis direction and displaying it on the waveform display screen 41.

[0044] In the screen-based display magnification change process, the process changeover switch 35 of the operation unit 3 is operated to output a process changeover signal ST1 to the control unit 5. When the screen-based display magnification change process is selected, for example, a control voltage RA2 corresponding to the resistance value at the position of the slider 32b is output from the second slide variable resistor 32a arranged in the operation unit 3 to the ADC 34, and a digital signal RD2 corresponding to the control voltage RA2 is output from the ADC 34 to the control unit 5.

[0045] As an example, the control unit 5 stores the digital signal RD2 at the center position of the slider 32b's slider movement range of the second slide variable resistor 32a in the memory unit 6 as a digital value RD2m, which is a reference value for stopping the screen-based display magnification change process, and constantly compares the digital value RD2m with the digital signal RD2 to set a display magnification according to the difference between an arbitrary digital signal RD2 that changes linearly from the digital value RD2m. At the same time, when the digital signal RD2 exceeds the digital value RD2m, the signal waveform W is enlarged in the time axis direction and displayed on the waveform display screen 41. When the digital signal RD2 is less than the digital value RD2m, the signal waveform W is reduced in the time axis direction and displayed on the waveform display screen 41.

[0046] In addition, in the cursor display position reference display magnification change process, when the process change switch 35 of the operation unit 3 is operated to output a process change signal ST1 to the control unit 5 and set to the cursor display position reference display magnification change process, a digital signal RD2 is output to the control unit 5 in a configuration similar to that of the above-mentioned screen reference display magnification change process.

[0047] The control unit 5 similarly stores the digital value RD2m in the storage unit 6 as a reference value for stopping the cursor display position reference display magnification change process, constantly compares the digital value RD2m with the digital signal RD2, and sets the display magnification according to the difference between any digital signal RD2 that changes linearly from the digital value RD2m. At the same time, in a state where the display position of the cursor 42a displayed on the waveform display screen 41 and the measurement data Dn displayed at that position are fixed, if the digital signal RD2 exceeds the digital value RD2m, the signal waveform W is enlarged and displayed in the time axis direction. Also, if the digital signal RD2 is less than the digital value RD2m, the signal waveform W is reduced in the time axis direction and displayed on the waveform display screen 41.

[0048] As another example of the operation unit 3, the operation unit 3′ is configured to be able to operate a process changeover switch 38 to switch and select between the cursor scrolling display process, the waveform scrolling display process, the waveform cursor scrolling display process, the screen-based display magnification change process, and the cursor display position-based display magnification change process, and a control voltage RA3 corresponding to the resistance value at the position of the slider 36b is output from a third slide variable resistor 36a arranged in the operation unit 3′ to the ADC 37, and a digital signal RD3 corresponding to the control voltage RA3 is output from the ADC 37 to the control unit 5.

[0049] The control unit 5 switches the use of the digital signal RD3 in accordance with the process selected by operating the process changeover switch 38, and executes any one of the cursor scroll display process, the waveform scroll display process, the waveform cursor scroll display process, the screen-based display magnification change process, and the cursor display position-based display magnification change process.

[0050] FIG. 4 is a diagram showing the display unit 4 when a signal waveform W is generated from a portion of the measurement data Dn stored in the memory unit 6 and displayed on the waveform display screen 41. The relationship between the signal waveform W and the cursor 42a in the cursor scroll display process will be explained using FIG. 4.

[0051] As an example, when a signal waveform W is displayed at maximum resolution on an XGA LCD display, the maximum resolution in the time axis direction (1024 pixels on the horizontal axis) corresponds to the number of samples of measurement data Dn that can be displayed at one time, so a maximum of 1024 pieces of measurement data Dn can be displayed.

[0052] Next, assuming that the coordinate X for displaying cursor 42a on an arbitrary time axis of waveform display screen 41 is coordinate X=0, with the left end of waveform display screen 41 as the origin, then in order to scroll cursor 42a in the right arrow direction on waveform display screen 41, cursor 42a is re-displayed while increasing coordinate X. Also, when it is desired to scroll cursor 42a in the left arrow direction on waveform display screen 41, cursor 42a is re-displayed while decreasing coordinate X. At this time, the slider 31b of the first slide variable resistor 31a of the operation unit 3 is positioned at the center of the slider movement range, and a digital signal RD1 of 512 counts is output to the control unit 5 and stored in the memory unit 6 as the digital value RD1m of the reference value.

[0053] As an example, the control unit 5 uses the difference obtained by subtracting the digital signal RD1 from the digital value RD1m stored in the memory unit 6 as a signed digital value RD1def as a judgment standard, and if the digital value RD1def is within the range of ±24 counts, a hysteresis is provided so that cursor scroll display processing is not performed, and the display position of the cursor 42a is maintained. From this state, by gradually moving the slider 31b of the first sliding variable resistor 31a from the center position of the slider movement range to one end or the other end, the digital value RD1def gradually changes, exceeding or falling below the hysteresis, and the cursor 42a is re-displayed while increasing or decreasing the change amount Xvar of the coordinate X depending on the polarity and amount of the difference, thereby scrolling the cursor 42a in the direction of the left arrow or the direction of the right arrow.

[0054] In the above example, the change amount Xvar of the coordinate X can be set to ±488 types obtained by subtracting the hysteresis from the digital value RD1m, so the speed at which the cursor 42a is scrolled can be set to a maximum of ±488 types.

[0055] As an example, in a state where the amount of change Xvar is set within the range of ±1 pixel to ±244 pixels each time the digital value RD1def increases or decreases by ±2 counts, when the cursor 42a is redisplayed every 0.5 seconds and the cursor 42b positioned at the coordinate X=0 (left end) on the waveform display screen 41 is scrolled to the position of the cursor 42c at the coordinate X=1023 (right end), the slider 31b of the first sliding variable resistor 31a is gradually moved from the center position of the slider movement range to the other end to set the amount of change Xvar with positive polarity, and the cursor is scrolled by the coordinate X+1023 pixels. At this time, the relationship between the time Tscr required for the movement of the cursor 42b and the amount of change Xvar is as follows: Tscr = 1023 ÷ Xvar × 0.5 [Equation 2] Specifically, if you set Xvar to -50, Tscr = 10.23 seconds (= 1023 ÷ (-50) × 0.5) If you scroll with and set Xvar to -224, Tscr = approx. 2.29 seconds (= 1023 ÷ (-224) × 0.5) to scroll.

[0056] For example, if the position of the cursor 42a is far from the desired position on the waveform display screen 41, the cursor display can be easily and quickly positioned to the desired position by moving the slider 31b of the first slide variable resistor 31a a relatively large amount from the center position of the slider movement range in accordance with the desired scrolling direction. Conversely, if the position of the cursor 42a is close to the desired position on the waveform display screen 41, the cursor display can be accurately and easily positioned to the desired position by moving the slider 31b of the first slide variable resistor 31a a relatively small amount from the center position of the slider movement range in accordance with the desired scrolling direction.

[0057] 5 and 6 are diagrams for explaining a case where, in a state where the waveform display screen 41 is displayed on the display unit 4, the cursor 42d is fixed at the center of the time axis of the waveform display screen 41 and displayed, and a waveform scroll display process is performed. As an example, in a state where a signal waveform W is generated and displayed from 1024 pieces of measurement data Dn out of 3072 pieces (three screens worth) of measurement data Dn stored in the storage unit 6, when it is desired to scroll the signal waveform W on the waveform display screen 41 in the right arrow direction, the target position is changed while decreasing the sampling number n, and the signal waveform W is redisplayed. Also, when scrolling the signal waveform W in the left arrow direction, the target position is changed while increasing the sampling number n of the referenced measurement data Dn, and the signal waveform W is redisplayed.

[0058] At this time, the operation unit 3 outputs the digital signal RD1 to the control unit 5 in the same configuration as the cursor scroll display processing, and the control unit 5 determines the digital value RD1def from the digital value RD1m stored in the memory unit 6 and the digital signal RD1 in the same processing as the cursor scroll display processing, and if the digital value RD1def is within the range of ±24 counts, a hysteresis is applied so that the waveform scroll display processing is not performed, and the display of the signal waveform W is maintained. From this state, by gradually moving the slider 31b of the first sliding variable resistor 31a from the center position of the slider movement range to one end or the other end, the digital value RD1def gradually changes, exceeding or falling below the hysteresis, and the change amount Nvar of the sampling number n is increased or decreased depending on the polarity and amount of this difference, and the reference position of the measurement data Dn to be displayed is changed to generate and re-display the signal waveform W, thereby scrolling the signal waveform W in the direction of the left arrow or the direction of the right arrow. The above-mentioned amount of change Nvar can set the speed at which the signal waveform W is scrolled to a maximum of ±488, similar to the cursor scroll display process.

[0059] As an example, in a state where the amount of change Nvar is set within the range of ±1 to ±244 each time the digital value RD1def increases or decreases by ±2 counts, while the signal waveform W is redisplayed every 0.5 seconds, the measurement data Dn located at the coordinate X=0 (left end) of the waveform display screen 41 as shown in Fig. 5 is scrolled to the coordinate X=1023 (right end) of the waveform display screen 41 as shown in Fig. 6, the slider 31b of the first sliding variable resistor 31a is gradually moved from the center position of the slider movement range to one end to set the amount of change Nvar of negative polarity, and the reference position of the measurement data Dn is scrolled to the sampling number n-1023. At this time, the relationship between the time Tscr required to scroll the signal waveform W and the amount of change Nvar is as follows: Tscr = 1023 ÷ Nvar × 0.5 [Equation 3] Specifically, when Nvar is set to -50, Tscr = 10.23 seconds (= 1023 ÷ (-50) × 0.5) If you scroll with and set Nvar to -224, Tscr = approx. 2.29 seconds (= 1023 ÷ (-224) × 0.5) to scroll.

[0060] For example, if the desired measurement data Dn to be displayed is located away from the signal waveform W displayed on the waveform display screen 41, the desired measurement data Dn can be easily and quickly displayed on the waveform display screen 41 by moving the slider 31b of the first slide variable resistor 31a a relatively large amount from the center position of the slider movement range in the direction of the desired scrolling. On the other hand, if the desired measurement data Dn to be displayed is located close to the signal waveform W displayed on the waveform display screen 41, the desired measurement data Dn can be accurately and easily positioned by moving the slider 31b of the first slide variable resistor 31a a relatively small amount from the center position of the slider movement range in the direction of the desired scrolling.

[0061] 7 to 9 are diagrams for explaining a case where the waveform cursor scroll display process is performed simultaneously with the above-mentioned cursor scroll display process and the above-mentioned waveform scroll display process while the waveform display screen 41 is displayed on the display unit 4. As an example, the operation unit 3 operates the slider 31b of the first slide variable resistor 31a in the same manner as the operations of the above-mentioned cursor scroll display process and the above-mentioned waveform scroll display process, and outputs a digital signal RD1 to the control unit 5.

[0062] The control unit 5 determines a digital value RD1def from the digital signal RD1 and digital value RD1m and digital signal RD1 previously stored in the memory unit 6, and scrolls the cursor 42a according to the digital value RD1def, as shown in FIG. 7, while simultaneously scrolling the signal waveform W in the opposite direction to the scrolling direction of the cursor 42a, thereby enabling the scrolling of the cursor 42a and the signal waveform W over a wider range to be performed accurately, easily and quickly.

[0063] Furthermore, on the waveform display screen 41, the scrollable range of the cursor 42a is set to a range of 257 pixels to 768 pixels on the coordinate X. When the coordinate X of the cursor 42a is below 257 pixels as shown in FIG. 8, or when the coordinate X of the cursor 42a exceeds 768 pixels as shown in FIG. 9, the display position of the cursor 42a is fixed and only the signal waveform W is scrolled. This makes it possible to scroll the cursor 42a and the signal waveform W accurately, easily and quickly while clarifying the position of the cursor 42a on the signal waveform W.

[0064] 10 to 12 are diagrams for explaining an example of screen reference display magnification change processing performed while the waveform display screen 41 is displayed on the display unit 4. For example, when 4093 pieces of measurement data Dn are stored in the storage unit 6, and the signal waveform W of the measurement data Dn is enlarged or reduced for display with the display data ratio CON=4 to the time axis resolution of the waveform display screen 41, the magnification at which the signal waveform W is displayed on the waveform display screen 41 is the display magnification MAG, the reference position (coordinate X) on the screen at which the signal waveform W is enlarged or reduced is the screen reference Xref, and the measurement data Dn displayed at the position of the screen reference Xref is the measurement data Dref, the relationship between the coordinate X of the waveform display screen 41 and the sampling number n of the measurement data Dn to be displayed is as follows: n=ref+(X-Xref)×CON÷MAG···[Formula 4] In the screen reference display magnification change process, the coordinate X of the center of the time axis of the waveform display screen 41 is used as the screen reference Xref for calculation, so that the screen reference Xref=511. n=ref+(X-511)×CON÷MAG···[Formula 5] The measurement data Dn is displayed as a signal waveform W on the waveform display screen 41.

[0065] Specifically, as shown in FIG. 10, when ref=2044 counts and the display magnification MAG=1 (1x), the sampling number n of the measurement data Dn to be displayed at the coordinate X is: Coordinates X=0:n=0(=2044+(0-511)×4÷1) Coordinate X=1:n=4(=2044+(1-511)×4÷1) Coordinate X = 2:n = 8 (=2044+(2-511)×4÷1) ... Coordinates X=1021:n=4084(=2044+(1021-511)×4÷1) Coordinates X=1022:n=4088(=2044+(1022-511)×4÷1) Coordinates X=1023:n=4092(=2044+(1023-511)×4÷1) As shown above, measurement data D0 to D4092 are displayed on the waveform display screen 41 with gaps between every three measurement data.

[0066] Furthermore, as shown in FIG. 11, when the display magnification MAG is set to 2 (2 times), the sampling number n of the measurement data Dn to be displayed on the coordinate X is Coordinates X=0:n=1022(=2044+(0-511)×4÷2) Coordinate X=1:n=1024(=2044+(1-511)×4÷2) Coordinate X=2:n=1026(=2044+(2-511)×4÷2) ... Coordinates X=1021:n=3064(=2044+(1021-511)×4÷2) Coordinates X=1022:n=3066(=2044+(1022-511)×4÷2) Coordinates X=1023:n=3068(=2044+(1023-511)×4÷2) As shown above, measurement data D1022 to measurement data D3068 are displayed on the waveform display screen 41 with a gap provided between each piece of measurement data.

[0067] Furthermore, as shown in FIG. 12, when the display magnification MAG is set to 4 (4 times), the sampling number n of the measurement data Dn to be displayed on the coordinate X is Coordinates X=0:n=1533(=2044+(0-511)×4÷4) Coordinate X=1:n=1534(=2044+(1-511)×4÷4) Coordinate X=2:n=1536(=2044+(2-511)×4÷4) ... Coordinates X=1021:n=2554(=2044+(1021-511)×4÷4) Coordinates X=1022:n=2555(=2044+(1022-511)×4÷4) Coordinates X=1023:n=2556(=2044+(1023-511)×4÷4) As shown above, the measurement data D1533 to D2556 are displayed on the waveform display screen 41 without any gaps.

[0068] At this time, the slider 32b of the second sliding variable resistor 32a of the operating unit 3 is positioned at the center of the slider movement range, and a digital signal RD2 of 512 counts is output to the control unit 5 and stored in the memory unit 6 as the digital value RD2m of the reference value.

[0069] As an example, the control unit 5 uses the difference obtained by subtracting the digital signal RD2 from the digital value RD2m stored in the memory unit 6 as the signed digital value RD2def as the judgment standard, and if the digital value RD2def is within the range of ±24 counts, a hysteresis is introduced so that the screen reference display magnification change process is not performed, and the display of the signal waveform W is maintained. From this state, by gradually moving the slider 32b of the second sliding variable resistor 32a from the center position of the slider movement range to one end or the other end of the movement range, the digital value RD2def gradually changes, exceeding or falling below the hysteresis, and by increasing or decreasing the display magnification MAG according to the polarity and amount of this difference, the signal waveform W generated from the measurement data Dn is enlarged or reduced and displayed on the waveform display screen 41.

[0070] When a sufficient amount of measurement data Dn necessary for the screen reference display magnification change process is stored in the memory unit 6, the display magnification MAG can be set to multiple types as divisors of the display data ratio CON, and can be set to a maximum of ±488 types obtained by subtracting hysteresis from the digital value RD2m.When the absolute value of the digital value RD2def is small, the amount of change in the display magnification MAG is set to a relatively small amount, and when the absolute value is large, the amount of change in the display magnification MAG is set to a relatively large amount. At the same time, when the polarity of the digital value RD2def is negative, the amount of change is added to the display magnification MAG, and when the polarity of the digital value RD2def is positive, the amount of change is controlled to be subtracted from the display magnification MAG. Thus, when it is desired to roughly enlarge the signal waveform W from its current display, the visibility can be improved easily and in a short time by moving the slider 32b of the second slide variable resistor 32a by a relatively large amount from the center position of the slider movement range to one end, and when it is desired to finely enlarge the signal waveform W, the visibility can be improved easily and with precision by moving the slider 32b of the second slide variable resistor 32a by a relatively small amount from the center position of the slider movement range to one end.

[0071] Furthermore, when it is desired to roughly reduce the signal waveform W from its current display, the visibility can be easily improved in a short time by moving the slider 32b of the second slide variable resistor 32a by a relatively large amount from the center position of the slider movement range to the other end. On the other hand, when it is desired to finely reduce the signal waveform W, the visibility can be easily improved with precision by moving the slider 32b of the second slide variable resistor 32a by a relatively small amount from the center position of the slider movement range to the other end.

[0072] 13 to 15 are diagrams for explaining an example of cursor display position reference display magnification change processing performed while the waveform display screen 41 is displayed on the display unit 4. For example, using a configuration similar to the screen reference display magnification change processing described above, if the magnification at which the signal waveform W is displayed on the waveform display screen 41 is the display magnification MAG, the coordinate X of the waveform display screen 41 displaying the cursor 42d is the screen reference Xref, and the measurement data Dn displayed at the position of the screen reference Xref is the measurement data Dref, then the relationship between the coordinate X of the waveform display screen 41 and the sampling number n of the displayed measurement data Dn is as follows: n=ref+(X-Xref)×CON÷MAG···[Formula 4] The measurement data Dn is displayed as a signal waveform W on the waveform display screen 41.

[0073] Specifically, as shown in FIG. 13, when Xref=304, ref=1216 counts, and the display magnification MAG=1 (1x), the sampling number n of the measurement data Dn displayed at the coordinate X is: Coordinates X=0:n=0(=1216+(0-304)×4÷1) Coordinate X=1:n=4(=1216+(1-304)×4÷1) Coordinate X=2:n=8(=1216+(2-304)×4÷1) ... Coordinates X=1021:n=4084(=1216+(1021-304)×4÷1) Coordinates X=1022:n=4088(=1216+(1022-304)×4÷1) Coordinates X=1023:n=4092(=1216+(1023-304)×4÷1) As shown above, measurement data D0 to D4092 are displayed on the waveform display screen 41 with gaps between every three measurement data.

[0074] Furthermore, as shown in FIG. 14, when the display magnification MAG is set to 2 (2 times), the sampling number n of the measurement data Dn to be displayed on the coordinate X is Coordinate X=0:n=608(=1216+(0-304)×4÷2) Coordinate X=1:n=610(=1216+(1-304)×4÷2) Coordinate X=2:n=612(=1216+(2-304)×4÷2) ... Coordinates X=1021:n=2650(=1216+(1021-304)×4÷2) Coordinates X=1022:n=2652(=1216+(1022-304)×4÷2) Coordinates X=1023:n=2654(=1216+(1023-304)×4÷2) As shown above, measurement data D608 to measurement data D2654 are displayed on the waveform display screen 41 with a gap provided between each piece of measurement data.

[0075] Furthermore, as shown in FIG. 15, when the display magnification MAG is set to 4 (4 times), the sampling number n of the measurement data Dn to be displayed on the coordinate X is Coordinate X=0:n=912(=1216+(0-304)×4÷4) Coordinate X=0:n=913(=1216+(1-304)×4÷4) Coordinate X=0:n=914(=1216+(2-304)×4÷4) ... Coordinates X=1021:n=1933(=1216+(1021-304)×4÷4) Coordinates X=1022:n=1934(=1216+(1022-304)×4÷4) Coordinates X=1023:n=1935(=1216+(1023-304)×4÷4) In this way, the measurement data D912 to D1935 are displayed on the waveform display screen 41 without any gaps.

[0076] At this time, by operating the second slide variable resistor 32a of the operation unit 3 in the same manner as the screen reference display magnification change process and outputting the output to the control unit 5 for control, if it is desired to roughly enlarge the signal waveform W from the current display, the visibility can be easily improved in a short time without losing sight of the measurement data at the position of the cursor 42d by moving the slider 32b of the second slide variable resistor 32a by a relatively large amount from the center position of the slider movement range to one end, and if it is desired to finely enlarge the signal waveform W, the visibility can be easily improved with precision without losing sight of the measurement data at the position of the cursor 42d by moving the slider 32b of the second slide variable resistor 32a by a relatively small amount from the center position of the slider movement range to one end.

[0077] Furthermore, when it is desired to roughly reduce the signal waveform W from the current display and display it, the visibility can be easily improved in a short time without losing sight of the measurement data at the position of the cursor 42d by moving the slider 32b of the second slide variable resistor 32a by a relatively large amount from the center position of the slider movement range to the other end. On the other hand, when it is desired to finely reduce the signal waveform W and display it, the visibility can be easily improved with precision without losing sight of the measurement data at the position of the cursor 42d by moving the slider 32b of the second slide variable resistor 32a by a relatively small amount from the center position of the slider movement range to the other end.

[0078] The operation unit 3' shown in Figure 3 includes a process changeover switch 38 for changing the operating conditions of the waveform display device 1, a third slide variable resistor 36a equipped with a slider 36b, and an ADC 37 for converting a control voltage RA3 output from the third slide variable resistor 36a into a digital signal, and outputs the digital signal RD3 output from the ADC 37 and a process changeover signal ST2 from the process changeover switch 38 to the control unit 5.

[0079] The control unit 5 sequentially switches between waveform scroll display processing, cursor scroll display processing, waveform cursor scroll display processing, cursor display position reference display magnification change processing, and screen reference display magnification change processing in synchronization with the change in the process switching signal ST2, and processes the selected processing using the digital signal RD3, thereby enabling the operation unit 3 to be constructed with fewer components and enabling the shape of the waveform display device 1 to be made smaller while keeping the cost down.

[0080] Furthermore, by constructing each of the sliders 31b, 32b, 36b of the slide variable resistors 31a, 32a, 36a from an insulating material and isolating them from the internal circuitry of the waveform display device 1, it is possible to easily insulate the measurement terminals (internal circuitry) from the exterior that the user can directly touch while maintaining a good insulating state.

[0081] The configuration of the "waveform display device" and the content of the "waveform display method" are not limited to the configuration of the waveform display device 1 and the content of the waveform display method by the waveform display device 1 described above. For example, the physical quantities that are the source of the "waveform data" are not limited to voltage values ​​and current values, and a configuration (method) for displaying waveforms for various physical quantities such as resistance values, power values, phases, temperature, humidity, luminance (light intensity), illuminance, sound volume, rainfall, and flow rate can be adopted. Although the waveform display device 1 integrally equipped with the measurement unit 2 has been described as an example, the configuration of the waveform display device is not limited to this, and a configuration (not shown) for displaying a signal waveform W based on measurement data Dn generated by a measurement device serving as an external device can also be adopted. Furthermore, the waveform display device 1 integrally equipped with the display unit 4 has been described as an example, but the configuration of the waveform display device is not limited to this, and a configuration (not shown) for displaying the signal waveform W on a display device serving as an external device can also be adopted.

[0082] Although the embodiment of the present invention has been described in detail above, the present invention is not limited to the above embodiment, and various design modifications can be made to the present invention without departing from the scope of the claims. [Explanation of symbols]

[0083] 1 Waveform display device 2 Measuring part 3,3' Control section 4 Display section 5. Control section 6 Memory section 31a, 32a, 36a Slide variable resistor 31b, 32b, 36b slider 33,34,37 ADC (Analog / Digital Converter) 35,38 SW (Processing changeover switch) Sig Input signal Dn Measurement data (n sampling number) RA1~3 control voltage RD, RD1~3 digital signal ST1~2 Processing switching signal 41 Waveform display screen 42, 42a~d Cursor (cursor display) X coordinate W signal waveform

Claims

1. a scroll display process for displaying a signal waveform based on waveform data on a waveform display screen, and displaying a cursor display for designating an arbitrary point on the signal waveform on the waveform display screen so as to be superimposed on the signal waveform, and for setting and scrolling an amount of scroll movement for scrolling at least one of the signal waveform and the cursor display relative to the other based on a resistance value of a first slide variable resistor to which a specific reference first resistance value is set, and a display magnification change process for setting a display magnification of the signal waveform based on a resistance value of a second slide variable resistor to which a specific reference second resistance value is set, and enlarging or reducing the display on the waveform display screen in a time axis direction, The processing unit, when the first slide variable resistor is operated while both the signal waveform and the cursor display are displayed on the waveform display screen, sets a movement amount and a movement direction for scrolling at least one of the signal waveform and the cursor display relative to the other based on the difference between the first resistance value and the resistance value of the first slide variable resistor, and when the second slide variable resistor is operated, sets the display magnification of the signal waveform based on the difference between the second resistance value and the resistance value of the second slide variable resistor, and displays the signal waveform on the waveform display screen by enlarging or reducing it.

2. 2. The waveform display device according to claim 1, wherein the display magnification change process, when the second slide variable resistor is operated, sets the display magnification of the signal waveform based on a time axis associated with the display position of the cursor display based on a difference between the second resistance value and the resistance value of the second slide variable resistor, and displays the signal waveform on the waveform display screen by enlarging or reducing it.

3. the processing unit is switchable depending on the scroll display process and the display magnification change process, and executes the scroll display process of setting the scroll movement amount and scrolling based on a resistance value of a third slide variable resistor to which a specific reference third resistance value is set, or the display magnification change process of setting the display magnification of the signal waveform and enlarging or reducing it in a time axis direction to display it on the waveform display screen, 3. A waveform display device as claimed in claim 1 or 2, wherein when the processing unit switches to the scroll display process or the display magnification change process and the third slide variable resistor is operated while both the signal waveform and the cursor display are displayed on the waveform display screen, the processing unit performs the scroll display process or the display magnification change process based on the difference between the third resistance value and the resistance value of the third slide variable resistor, and displays the signal waveform on the waveform display screen.

4. 4. The waveform display device according to claim 3, wherein the slider of the first slide variable resistor, the slider of the second slide variable resistor and / or the slider of the third slide variable resistor are insulated from an internal circuit of the waveform display device.

5. 4. The waveform display device according to claim 3, wherein said first slide variable resistor, said second slide variable resistor and / or said third slide variable resistor are self-resetting.

6. 1. A waveform display method which executes a scroll display process for displaying a signal waveform based on waveform data on a waveform display screen, and displaying a cursor display for designating an arbitrary point on the signal waveform on the waveform display screen superimposed on the signal waveform, and setting and scrolling an amount of scroll movement for scrolling at least one of the signal waveform and the cursor display relative to the other based on a resistance value of a first slide variable resistor having a specific reference first resistance value set thereto, and a display magnification change process for setting a display magnification of the signal waveform based on the resistance value of a second slide variable resistor having a specific reference second resistance value set thereto, and enlarging or reducing the display on the waveform display screen in a time axis direction, a waveform display method in which, when the first slide variable resistor is operated while both the signal waveform and the cursor display are displayed on the waveform display screen, a movement amount and a movement direction for scrolling at least one of the signal waveform and the cursor display relative to the other are set based on a difference between the first resistance value and the resistance value of the first slide variable resistor, and, when the second slide variable resistor is operated, a display magnification of the signal waveform is set based on the difference between the second resistance value and the resistance value of the second slide variable resistor, and the signal waveform is enlarged or reduced when displayed on the waveform display screen.

Images