JPH07260519A - Display device - Google Patents

Abstract

PURPOSE: To provide a display device by which at least two levels, which are functionally independent mutually and are derived separately, of a signal can be easily and totally comprehended at a glance. CONSTITUTION: A display device displaying an effective value level and a peak value level of a signal at the same time is provided with a scale 6, an array 2 consisting of plural display elements 4, and a controlling means controlling these display elements 4. By means of the controlling means, the effective value level is indicated by a bar 12 formed of the display elements 4, and the peak value level is indicated by a moving spot 14 formed of the display elements 4. The peak value level is displayed only in a display area in the upper part of the scale.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device, and more particularly, to a program meter for displaying various signal levels such as an effective value level and a peak value level of an audio signal in an electric device for audio processing. And other display devices.

[0002]

The simplest of the various display devices for displaying signal levels is the program meter in the form of a VU meter. The VU meter uses a moving coil mechanism and a rectifier circuit to generate a DC meter drive signal from an AC audio input signal. The VU meter displays the perceived total loudness when maintaining the average level of the perceived total loudness of the program material composed of the audio signal at a substantially constant level. The VU reading is calibrated so that

[0003]

Although VU meters are suitable for "line-up" processes (where the line-up process involves the adjustment of multiple components according to a steady-state signal supplied). The VU meter is
It only represents the overall volume, not the peak value level. This is a disadvantage in situations where most of the conditions in the program editing work relate to peak limits.

It is also possible to modify the basic structure of the VU meter so that the peak value level of the signal can be displayed more. However, the rise time is about 10 dB / msec for a meter that uses a moving coil.
Since there is a difficult constraint that it is about 10 dB (10 dB is 10 dB in the meter display), even a meter with such a modification will underestimate the peak with a short duration.

With bias recording systems employed in tape equipment, underestimating short duration peaks is usually not a problem. This is because even a peak that causes distortion does not cause listener discomfort if it is a short-duration peak, and the signal to which the harmonics are added by the distortion already has a large amount of harmonics. This is because the waves are included. Furthermore, the distortion starts to increase gradually after the peak value level becomes larger than the nominal peak value level, so if the recording level is set according to the peak signal, the channel utilization will be too low. turn into.

On the other hand, in applications other than recording, the rise time of the meter for displaying the peak value is long, and therefore when the rise time is slow, it is necessary to compensate to compensate for it. For example, it is also possible to provide the compensation during the transmission of the signal, in order to do so, by passing it through a compression circuit and a limiter in order to reduce the signal peaks not detected by the meter measurement. Further, there is a method of preventing the occurrence of clipping by providing the headroom of the mixing console (operator console) far above that of the tape channel. Headroom here refers to the dynamic range of the program channel above the peak display value of the meter used to allow for the gap between the displayed peak value level and the true peak value level. Is defined as part of. Of course, this definition has limited value in situations where each broadcast technician or operator uses a different program meter, and is even truer like a digital peak value meter. It is meaningless for a meter that indicates the peak value of.

Generally speaking, analog meters are associated with misalignment problems. Analog meters may not be properly assembled and, obviously, the more complex the meter, the more alignment that needs to be changed. In addition, VU
The meter can also introduce a simple level error,
Peak value meters also require consideration of the instantaneous driving force for both rise and fall times.

A digital meter is advantageous in that it has a short rise time and an instantaneous rise, and that it can indicate a true peak value. In addition, the digital meter is
It is also possible to measure and display the rms value, and since the rms value indicates a true power indication value, it can be said that it is a value that reasonably represents the volume of the program.

In the field of programming, it is possible for the operator to ensure that the peak value level of the program signal falls within the range of the channel, or to visually display the perceived volume level of the program signal,
There is a desire to provide a display device that allows the operator to properly balance several levels according to artistic demands, which none of the above-mentioned meters have hitherto met. is there.

In particular, while digital meters are capable of displaying true peak values, the operator need only display the true peak value to properly adjust the number of signal levels in accordance with the artistic requirements of the program material. It cannot be balanced.

On the other hand, in order to display the loudness of the sound, it is sufficient to display the effective value of the signal, but this is incompatible with the display of the true peak value, and the reason is that the effective value and the peak. This is because the relationship with the value is not constant and changes according to the content of the program signal.

[0012]

SUMMARY OF THE INVENTION The present invention provides a display device for simultaneously displaying at least two functionally independent and individually derived levels of a signal, the display device comprising: A scale for a display and an indicator for displaying the level, wherein the indicator is adapted to be displayed according to the position of the indicator along the scale, and a plurality of selectable units along the scale The first level of the signal is displayed using the indicator in a first region of positions, and at the same time, the first level of the signal is displayed.
The display of the level is a visually identifiable display form, and the second level of the signal is displayed using the indicator in the second area consisting of a plurality of selectable positions along the scale, and further, It is characterized in that the second area and the first area are provided with a control means for displaying the levels by having an overlapping portion.

By using this display device, the operator can easily and simultaneously recognize two signal levels representing the signal characteristics represented by the levels. In particular, if the first level is the rms level of a signal and the second level is the peak level of the signal, the operator adjusts the rms level, or It is possible to balance a plurality of RMS levels displayed on the display device with each other, and when the peak value level becomes excessive while adjusting or balancing the RMS values, it is possible to easily see it. .

The display device comprises an array of a plurality of display elements each having at least two visually distinguishable states, the control means being arranged to select a display state of the display elements. However, it is preferable that the pointing unit includes a display element in a selected display state. Further, the visually identifiable state may include one color for displaying the first level and another color for displaying the second level, and It is preferable that each of the display elements can be used to display any level.

The first level is displayed by a plurality of display elements arranged in a row in a selected display state, and the row of the display elements displays the first position and a level lower than the first position. Preferably, the first level is selected to extend between the first predetermined position and the first predetermined position, and the first level is selected when the first level is lower than the level represented by the first predetermined position. It is also possible to display by one or a plurality of display elements which are in the display state and are substantially in the first position.

By doing so, the first level will be displayed in the form of a bar only when it is in a range useful to the operator. However, even low levels are in the form of "moving spots", and the level is displayed in all areas up to the digital silence state, which is particularly useful for surely eliminating stray noise. Is.

Further, the second region is located at a first predetermined position, which is higher than the first predetermined position, from the second predetermined position, and then the first predetermined position.
It preferably extends to the end of the region representing the highest level. By doing so,
As a result, the peak value level, which is the second level, is displayed only when it is at a relatively high level, and disappears when it is lower than the second region. This makes it possible to prevent the operator's misunderstanding. In addition, the operator can grasp a plurality of meters, each of which corresponds to a different channel, at a glance, and from which of the meters the peak value level is displayed, which channel is displayed? It becomes possible to judge whether or not it needs to be further attenuated.

[0018]

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. As shown in FIG. 1 of the accompanying drawings, there has been proposed a display device in which two meters are arranged side by side and one of them indicates a peak value and the other indicates an effective value.

However, with such two meters, it is difficult to comprehensively grasp the contents represented by the meters, and in particular, the indicated values of the meters are continuously changing, Moreover, when it is important for the operator to grasp the contents represented by the meters only by glancing at the meters, the difficulty becomes serious.

A display device embodying the present invention is shown in FIG.
It was shown to. This display device is provided with an array 2 composed of a plurality of display elements (segments) 4 and a scale 6 attached to the array 2 so that a relative signal level or an absolute signal level can be read.

The array 2 is further provided with a control unit as shown in FIG. 7, which will be described later in detail. The control unit energizes the specific segment 4 according to the level of the signal derived from the input signal. In this case, the signal levels derived from the input signal are specifically the effective value level and the peak value level. The limit level, which is the absolute upper limit of the level, corresponds to the rightmost portion of the scale shown, and lower levels are indicated by energizing the middle segment in the array.

The low RMS signal level is such that only a small number of adjacent segments 8 are energized for display, ie, "moving spots". In this case, one position on the array 2 with respect to the scale 6 is displayed (see FIG. 3). On the other hand, if the RMS signal level exceeds a predetermined threshold level corresponding to the number "8" on the scale shown in the figure, for example, the threshold (number "8") is displayed to display the signal level. The bar 12 is formed by urging and forming a series of segments corresponding to the signal level. To set this threshold, set the array to display the rms level as a bar only when the rms level is large enough to make sense for the particular application of the meter. Preferably.
Further, as will be discussed in more detail below, in setting this threshold, when the RMS level is at a normal balanced level suitable for the particular application, as shown in FIG. It is preferable to set so as to extend substantially in the central portion. Further, in particular, it is preferable to standardize the aspect ratio of the program display area so that the operator can become familiar with the length of the bar corresponding to a specific volume. An example of a suitable meter is to display a bar on a common logarithmic scale (log ₁₀ scale) so that the indicated value can be read anywhere in the whole range of the scale and at any part of the scale. It is a thing.

As shown in FIGS. 4 and 5, the peak value level is indicated by a "moving spot" 14, which also activates a small number of adjacent segments. It is something that is generated. The relationship between the peak value level and the RMS value level depends on the waveform of the signal, for example, in a waveform that normally goes high at low levels and sometimes high, the RMS value is low,
The peak value level becomes high, and the display in that case becomes as shown in FIG.

On the other hand, as mentioned above, the display of the peak value level is generally required to prevent the clipping of the signal from occurring in the channel whose level height is limited. Only for that purpose. Therefore, the peak value level of the signal is important only when the peak value level is relatively high. Therefore, in this embodiment, the display area for displaying the peak value level is
As shown in FIG. 1, it is limited to the upper region of the array of display elements. As a result, when the signal waveform has a low peak value level, only the RMS value level is displayed as shown in FIG. 3, while the signal waveform has a peak value even if the RMS value is low. When the value level is high, the peak value is displayed as long as it has a sufficient size to reach the peak display area.
In this way, by not displaying the low peak value level, there is no possibility that the two "moving spots" 8 and 14 are mistakenly recognized.

The present preferred embodiment can be devised, for the first time, by recognizing the following fact, which means that no matter how low the peak value level is,
It is at least as high as the RMS level (for square waves and DC signals), and usually higher than the RMS level. Therefore, even if the peak value level is displayed using the same segment that displays the RMS value level, the peak value level is always higher,
The effective value level and the peak value level can be visually distinguished.

To explain this in more detail, the calculation of the effective value level is performed within the sampling window of a predetermined period. The duration of this sampling window is preferably chosen so that an rms level is calculated which corresponds well with the level of sound perceived by the human ear. Each sampling window period is associated with a decay time, which delay time can be measured by applying an impulse input to the circuit. For good operation, the decay time of the peak level (which can be chosen arbitrarily) should be set equal to the decay time of the rms level. In addition, if the decay time of the peak value level is made equal to the decay time of the effective value level, or if it is set to decay more gently than that,
The peak value level will never be lower than the RMS value level.

The size and number of display elements may differ depending on the meter, and for example, 6 dB may be displayed by two segments in applications where low cost and compactness are required. On the other hand, for more important and perhaps larger applications, 6 dB
It is also possible to display 6 or 12 or more segments. However, no matter how many segments are allocated, the aspect ratio of the entire array should be the same.

This array can be constructed in various forms, for example, it can be constructed by arranging the light emitting diodes in a line, or by an elongated liquid crystal display. Further, in such a case, the signal level may be displayed by lighting a specific light emitting diode on the array 2 or darkening a specific segment.

Since this meter is a digital meter, the rise time in the peak value level indicating region can be made very short so that it can rise instantaneously, and in practice it is preferable, but However, it is preferable to set the fall time to about 6 dB / sec so that the operator has enough time to read the scale of the displayed signal level.

It would be very useful to be able to display the entire dynamic range of a program channel, or at least approximately the entire range. Up to now, when designing a program meter for an analog channel, the program meter expresses the dynamic range of that analog channel in dB and expresses it as 5 dB.
I tried to display the corresponding part between 0% and 100%, but by including the entire dynamic range, or almost the entire dynamic range, even a signal recorded at a volume level that was inadvertently too low can be displayed on the meter. You will be able to discover and take action to amplify that signal. On the other hand, in digital channels and professional equipment, the available dynamic range is about doubled because the broadcasting channels and listening environment are almost constant. Therefore, even if a source with a wide dynamic range, such as an in-car CD, a mini disk, or digital audio broadcasting, is used, the program signal is balanced over the entire dynamic range of the recording channel or the transmission channel. Often, this is not the case, because, for example, in the passenger compartment of an automobile running at high speed, the audible dynamic range is generally narrowed, so that low-level signals are less important.

The illustrated meter is particularly advantageous in terms of the above because the graduations of the graduations are varied midway along the length to provide a display area where the meter is used to balance the program signals. Tick marks,
This is because the graduations on the other display areas are different. Therefore, for the values below the program display area, that is, below the value "9" in the illustrated example, the graduation of the meter is different. What kind of scale is actually used may be selected in consideration of cost and operational requirements according to a specific application. One preferable example thereof is that the scales to be attached to the array of display elements are assigned numbers from the top, that is, from the maximum signal level, in accordance with the rule that the numbers assigned to the absolute limit peak value levels are the same. is there. For example, if the scale is set to 6 dB, it is sufficient to enter 6, 12, 18, ... In dB units for each scale of the scale. Alternatively, as shown in the figure, simply, from 0 to 1, 2, ...
You may also enter "...". In the lower area,
It is conceivable that the scale is a linear scale or a logarithmic linear scale, that is, it is conceivable that the scale in the upper region is different from the preferred common logarithmic scale. That way,
From the absolute limit peak value to a certain predetermined value, it is possible to make the intervals of entering the numbers on the scale equal, and to compress the scale when the predetermined value is exceeded. In the area of a predetermined value or less, the scale line of the scale may or may not have a number depending on the necessity. However, it is preferable that both the minimum program signal level of the meter and the level of each notched line are easily determined.

The minimum signal level that can be displayed may be different for each individual meter, and this minimum signal level may also be determined according to the specific application.

In digital systems, the absolute limit peak value level is often used as a reference, because it has the same absolute limit peak value level for different word sizes, so that it can be used for instruments with different resolutions. This is because the absolute limit peak value level serves well as a reference. A lineup level that is defined relative to the absolute limit peak value is also used. The lineup level determined in that way,
Since it is based on the absolute limit peak value, it is a constant level that does not differ between devices.

When a lineup tone is being input to this meter, its level can be read from the moving spot represented by the peak level and an adjustment can be made to that level, which is arbitrary. It can be done in a similar manner as is done with digital peak value meters. However, in order to be able to do this, the peak level display area is sufficiently low to contain all standard lineup levels, that is, 24 dB below the absolute limit peak level. It is necessary to have a suitable configuration.

Continuing with this further, the lineup level not only provides a standard level for gain setting throughout the program editing work, but also should be a criterion for the level of the program level. It also provides a reference point on the meter that can be used as a measure of the average or target level. Therefore, if a certain program level displayed in the form of a bar frequently moves above and below this point, it can be determined that the program level is at the target level. This state also corresponds to the state in which the bar extends in the central part of the display area, as shown in FIG. 5 and as explained above.

The needle-type meter conventionally used to display the program level will now be described. In the needle-type meter in which the pointer tilts to the left and right, the level corresponds to the center point of the scale, that is, It has been said that it is preferable to set the lineup level to a level where the pointer stands vertically. In this case, when the program balance is obtained, the average position of the pointer is located near the center point.

In one embodiment of the present invention, as shown in FIG. 6, the bar display portion of the meter is formed in an appropriate shape so that the above situation of the needle type meter can be simulated. That is, the whole is formed in a chevron shape and the position of the apex angle 16 is aligned with the center of the program level area, which makes it easier to read the program level at a glance. Because if the bar is just a straight line, the program level at that time is below average, while
If the bar has a bent shape, the program level at that time is above the average.

Needless to say, the form of the display portion of the meter can be various forms other than the form of the linear bar as shown in FIGS. Also, in multi-channel applications, you can arrange multiple bars vertically
It is preferable to facilitate a "glance comparison" with the surrounding channels.

As shown in the functional block diagram of FIG. 7, the meter of this preferred embodiment includes a receiving section 18, which receives the digital audio signal on a line 20.
It is preferable that the signal related to the left signal, the right signal, the sum signal, or the difference signal is also received from the line 22.

The receiving section 18 can be composed of an arithmetic unit which operates in response to a signal from the line 22. Specifically, for example, the digital audio signal on the line 20 may be the left signal and the right signal in the stereo signal. Further, in such a case, the signal on the line 22 may act so as to cause the receiving unit 18 to supply the next respective signals to the subsequent circuits. These signals are a) only the right signal. , B) left signal only, c) left and right sum signal (This signal is supplied in order to prevent the total signal level from exceeding the limit level of the channel by using the meter. There is a)) or d) a left-right difference signal (this signal is supplied in order to allow a meter to display "how much the signal is stereo-ized"). .

The receiver 18 includes lines 24 and 26.
Signals are output to the respective units via the, and the outputs are individually processed to display the effective value level and the peak value level of the signal.

This device includes a weighting circuit 28 in the path on the RMS measurement side, which weights the frequency response to match it with the frequency response of the human ear. To do so.

It is often practiced to use pre-emphasis circuits to increase channel utilization, but the use of pre-emphasis circuits does not affect the perceived loudness. It should be noted that the pre-emphasis circuit is always used in combination with the de-emphasis circuit.
Therefore, if the signal to be measured is pre-emphasized, if you want to measure the utilization of the channel, you should measure the signal with the meter still pre-emphasized. On the other hand, if the RMS level is to be measured, it must be measured after removing the pre-emphasis from the signal.

Therefore, the meter of FIG. 7 is provided with the de-emphasis circuit section 30 only on the RMS level measuring side.

It is preferable to combine the weighting function and the de-emphasis function into one function.

On the RMS value level measuring side, the RMS value conversion unit 32 subsequently calculates a series of RMS values by calculating each RMS value from a predetermined number of samples.

The calculated effective value level is supplied to the program display area detection unit 34, where it is determined whether or not the calculated effective value level is sufficiently high to reach the program display area. Is determined, and then
Based on the result of the determination, the logarithmic step conversion and bar generation unit 36 uses a lookup table to generate the data required by the combining unit 38 and the display driving unit 40.

On the other hand, on the peak value level measuring side, the signal from the line 24 is first rectified by the rectification unit 42, and then the rectified signal is subjected to conversion processing by the logarithmic step conversion unit 44.

When the output of the logarithmic step conversion section 44 is supplied to both the peak value detection section 46 and the peak value display area detection section 48, and the peak value level is a low level which does not reach the peak value display area. First, the peak value display area detection unit 48 controls the peak value display area gate 50 to prevent the peak value level from being transmitted to the coupling unit 38 and the display driving unit 40.

This meter has a suitable structure in which the overload indicator 52 can be incorporated. The overload indicator 52 is, for example, the main display section 2 of the display.
It is possible to form an additional segment that is provided above the main display portion 2 separately from the above, and it is optional to make the color of this additional segment different from the color of the main display portion 2. . When the overload detection unit 54 detects that a predetermined number of samples at the peak value upper limit level (the level corresponding to the number “0” on the scale) occur consecutively, the overload display segment is turned on and the channel is turned on. Indicates that overmodulation has occurred.

As shown in FIG. 7, the data from the logarithmic step conversion and bar generation unit 36 and the data from the peak value display area gate 50 can be sent to the telemetry output unit 56. .

As yet another embodiment, it is conceivable that the meter is simply configured to receive information and display it on the display.

Digital transmission of the signal enables telemetry. Also, for simple stereo applications, the meter may be equipped with any of a variety of standard digital audio interfaces. Further, if a meter measuring device is configured, for example, a display section, a power supply and a digital audio input section, and a digital audio through connection (multi-channel equipment is equipped with its own dedicated meter interface). It is often the case).

The advantage provided by the telemetry system is that the metering data can be transmitted in a much more compressed state than the original audio data, and the bar bar graph update rate is 50 per second. It is appropriate for normal human vision to make it more than once.

An interface used in the embodiment of the present invention is, for example, AES / EBU serial data.
Audio standards can be used, in which case the metering data is sent from the metering circuit at a set rate corresponding to medium speed. This rate is the rate at which one meter sample is sent for every 960 audio samples sent, in other words, 50 meter samples per second when the audio sample sending rate is 48kHz. Is the rate at which is sent. The transmission rate corresponding to the medium speed does not necessarily have to match the display update rate, and it is conceivable that the display update rate can be changed according to each display method. Further, in order to facilitate the change of the display update rate, the display drive section may be incorporated with an update rate conversion section.

In the AES 2-channel digital audio interface, the block transfer rate is 250 blocks per second. Therefore, if the meter data is transferred via this connection, it is sufficient to send the value of the meter data of the channel only once while sending five blocks. This standard defines two sizes of transferable words, one of which has 24 bits and the other of which has 20 bits. To transfer a smaller word, it is sufficient to fill the area below the LSB of the word with "0". If transmitting a 20-bit word, 4 bits can be used as a low quality communication channel. If a special version of this interface is created, those 4 bits can be used for the transfer of meter data. If the other 20 bits are used for carrying an audio signal, this connection can supply meter data corresponding to a plurality of channels and also a stereo monitor signal supply.

When the resolution is set to 8 bits, when the dynamic range is 128 dB, the accuracy of 0.5 dB can be obtained over the entire dynamic range. This accuracy value is probably more than adequate for most applications. When the resolution is set to 8 bits, one 8-bit word is required for meter data that represents the effective value, and another 8-bit word is required for meter data that represents the peak value. is there. The value of the data for the meter of the audio channel can be in the form of a block of, for example, 4 bits each.
The sub-frame data forms the lower nibble (4 bits), and the first sub-frame data forms the upper nibble. Also, the effective value data of the first channel is transmitted in the first frame, and the peak value data is transmitted in the second frame. A device with only eight channels will fit in the first 16 frames in a block, and a device with 48 channels will fit in the first 96 frames in a block. It will be.

Two audio samples, that is, two subframes make up one frame, and 192 frames are present in one block.
One audio sample contains four bits available for the transfer of meter data, so
A total of 1536 bits are available per block. This capacity is for 96 channels of meter indicating data when 16 bits (8 bits for effective value and 8 bits for peak value) are required for one meter indicating data of one channel. Sufficient capacity to transfer. Since the meter data transfer interval is sufficient once for every five frames, the maximum possible transfer capacity of meter data when sending out over a single connection is a total of 480 channels. It turns out that

This capacity easily satisfies the capacity required for the connection between the processing rack of the audio console and the meter section, for example. In addition, this capacity is compatible with the currently used 96-channel or 128-channel large-scale consoles, and can be used for future expansion. For example, in a digital multi-rack recorder or the like, 96 channels is a sufficient number of channels, and the maximum number of channels normally used is 48, which is the number of channels for transmitting an audio meter. Although not as many channels are needed, they can be used for the transfer of other information. Specifically, for example,
It is conceivable to measure the error rate and display it next to the audio meter, or display it instead of the audio meter. In order to make this possible, the transfer capacity of the meter data is limited so that the maximum number of channels of the meter data per block is 64 channels. That is, the number of channels per one is limited to 320 channels in total. By limiting in this way, a transfer capacity of 64 bits per block can be floated, and this transfer capacity can be used for carrying subcodes that clearly indicate allocation of other data. One of the possible functions of the meter data subcode is to clearly indicate on which channel in the block the meter data is carried. On a 96 channel console, for example, the first block could send 62 channels, the next block could send 32 channels, and the next three blocks could be blank blocks. Blocks are flagged to show them. The flag attached to the block indicates which channel is being transmitted and can be included in the subcode of the meter data. For example, the following combinations are required. 0) No meter data in this block 1) Channel 1 to channel 2) Channel 65 to channel 128 3) Channel 129 to channel 192 4) Channel 193 to channel 256 5) 257 Channel-Channel 320

At the top of these combinations, the data contained in the block is flagged so that the data is error rate information, DC level, fader position, or any other similar useful value. You may make it show that it is information data.

[0061]

Since the display device according to the present invention is configured as described above, if the operator balances the program level of the audio signal, the same signal such as the effective value level and the peak value level of each signal can be obtained. It is possible to easily and comprehensively grasp at least two functionally independent levels independently derived from each other by simply glancing at the display device, and therefore, the balance adjustment work can be performed very efficiently. It has an excellent effect of.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a configuration related to a proposal to provide an effective value display meter and a peak value display meter side by side.

FIG. 2 is a diagram showing a meter and a scale having a basic configuration according to an embodiment of the present invention.

FIG. 3 is a diagram showing a state in which the meter of FIG. 2 is displaying a low level signal.

FIG. 4 is a diagram showing a state in which the meter of FIG. 2 displays a signal having a low effective value level and a high peak value level.

FIG. 5 is a diagram showing a state in which the meter of FIG. 2 has a medium effective value level falling within a program display area and is displaying a signal having a higher peak value.

FIG. 6 is a view showing a display device according to another embodiment of the present invention.

FIG. 7 is a functional block diagram showing a control unit of the display device according to the present invention.

[Explanation of symbols]

 2 array 4 display element (segment) 6 scale 8 moving spot 12 bar 14 moving spot

Claims (12)

[Claims] 1. A display device for simultaneously displaying at least two functionally independent and individually derived levels of a signal at the same time, a scale for the display and an indicator for displaying said level. , A signal indicating the position of the indicator along the graduation so as to display the indication, and the indicator in the first region consisting of a plurality of selectable positions along the graduation. The first level is displayed, and at the same time, the indicator in the second area consisting of a plurality of selectable positions along the scale is used in a display form visually distinguishable from the first level display. The second level of the signal is displayed by the second area and the first area.
A display device, comprising: a control unit configured to display an area having an overlapping portion. 2. The first level is an effective value level,
The display device according to claim 1, wherein the second level is a peak value level. 3. The control means includes first means for calculating an effective value of the signal and second means for detecting a peak value of the signal. 2. The display device according to item 2. 4. An array comprising a plurality of display elements each having at least two visually distinguishable states, said control means being configured to select a display state of said display elements, 4. The display device according to claim 1, 2, or 3, wherein the pointing unit includes a display element in a selected display state. 5. The at least two visually identifiable states include one color for displaying the first level and another color for displaying the second level. The display device according to claim 4, wherein: 6. A display device according to claim 4, wherein each of the display elements can be used for displaying any level of the signal. 7. The display device according to claim 4, wherein the second level is displayed by one or a plurality of display elements in a selected display state and substantially in the second area. 5. The display device according to 5 or 6. 8. The first level is displayed by a plurality of display elements arranged in a row in a selected display state, and the row of the display elements is lower than the first region and the first region. The display device according to any one of claims 4 to 7, wherein the display device is configured to extend between a first predetermined position indicating a level. 9. When the first level is lower than the level represented by the first predetermined position, one or a plurality of the first levels are in the selected display state and substantially in the first area. 9. The display device according to claim 8, wherein the display device is configured to display by one display element. 10. The second region extends from a second predetermined position, which represents a level higher than the first predetermined position, to an end of the first region, which represents the highest level. The display device according to claim 8 or 9. 11. The display device according to claim 4, wherein the display element is a light emitting element or a liquid crystal element. 12. The display device according to claim 1, wherein the scale is divided into at least two parts having different scale divisions.