CA1257909A - Variable colour analog voltmeter - Google Patents
Variable colour analog voltmeterInfo
- Publication number
- CA1257909A CA1257909A CA000553862A CA553862A CA1257909A CA 1257909 A CA1257909 A CA 1257909A CA 000553862 A CA000553862 A CA 000553862A CA 553862 A CA553862 A CA 553862A CA 1257909 A CA1257909 A CA 1257909A
- Authority
- CA
- Canada
- Prior art keywords
- colour
- signal
- value
- limit
- analog
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R13/00—Arrangements for displaying electric variables or waveforms
- G01R13/40—Arrangements for displaying electric variables or waveforms using modulation of a light beam otherwise than by mechanical displacement, e.g. by Kerr effect
- G01R13/404—Arrangements for displaying electric variables or waveforms using modulation of a light beam otherwise than by mechanical displacement, e.g. by Kerr effect for discontinuous display, i.e. display of discrete values
- G01R13/405—Arrangements for displaying electric variables or waveforms using modulation of a light beam otherwise than by mechanical displacement, e.g. by Kerr effect for discontinuous display, i.e. display of discrete values using a plurality of active, i.e. light emitting, e.g. electro-luminescent elements, i.e. bar graphs
-
- G—PHYSICS
- G04—HOROLOGY
- G04G—ELECTRONIC TIME-PIECES
- G04G9/00—Visual time or date indication means
- G04G9/02—Visual time or date indication means by selecting desired characters out of a number of characters or by selecting indicating elements the position of which represent the time, e.g. by using multiplexing techniques
- G04G9/04—Visual time or date indication means by selecting desired characters out of a number of characters or by selecting indicating elements the position of which represent the time, e.g. by using multiplexing techniques by controlling light sources, e.g. electroluminescent diodes
Abstract
VARIABLE COLOUR ANALOG VOLTMETER
ABSTRACT OF THE DISCLOSURE
A voltmeter includes a variable colour analog display for providing an analog indication of the value of a measured signal in a colour in accordance with the relation of the measured value to predetermined limits.
ABSTRACT OF THE DISCLOSURE
A voltmeter includes a variable colour analog display for providing an analog indication of the value of a measured signal in a colour in accordance with the relation of the measured value to predetermined limits.
Description
~.~s~q3~ 3 VARIABLE COLOUR ANALOG VOLTMETER
BACKGROUND OF THE INVENTION
1. Field of the Invention This invention relates to measuring devices utilizing variable colour analog display.
BACKGROUND OF THE INVENTION
1. Field of the Invention This invention relates to measuring devices utilizing variable colour analog display.
2. Description of the Prior Art Monochromatic analog dispLay devices for displaying information in a bar graph Eormat are well known and extensively used. Commercially available bar display array usually consists of ten matched LEDs of the same colour.
Multicolour bar display arrays are also known that contain combinations of red, green and yellow LEDs arranged in a predetermined sequence. Such colour sequences are fixed and cannot be changed.
It is feasible to construct a simple analog voltmeter for visually indicating the level of a measured signal by combining a monochromatic bar display array with a suitable bar or dot driver chip. Such a voltmeter, however, is capable of indicating only the measured value; it is not capable of simultaneously indicating the measured value and its relation to measurement limits.
A device for producing an illuminated band representation of measured voltage is disclosed in UO S. Patent No.
Multicolour bar display arrays are also known that contain combinations of red, green and yellow LEDs arranged in a predetermined sequence. Such colour sequences are fixed and cannot be changed.
It is feasible to construct a simple analog voltmeter for visually indicating the level of a measured signal by combining a monochromatic bar display array with a suitable bar or dot driver chip. Such a voltmeter, however, is capable of indicating only the measured value; it is not capable of simultaneously indicating the measured value and its relation to measurement limits.
A device for producing an illuminated band representation of measured voltage is disclosed in UO S. Patent No.
3,961,256 issued on June 1, 1976 to Colin Simister Gaskell et al. The device relies on analog comparators for comparing the measured value with predetermined limits. When the measured value is within the limits, the band is fully ~ .57 ~
illuminated, without simultaneously indicating the limits.
When the measured value exceeds the limits, the portion of the band below the low limit is fully illuminated, the portion of the band between the limits is flashed on and off, to attract attention of an operator, and the portion of the band above the high limit is extinguished, to indicate the limit points, without simultaneously indicating the actual measured value.
Such a concept is not usable in a moving dot type display voltmeter wherein the value of measured voltage is indicated by the position of a single illuminated LED, because it is impossible to simultaneously fully illuminate the single LED, flash it on and off, and extinguish it.
~ ~ ~7130 S~MMARY OF THE INVENTION
Accordingly, it is the principal object of this invention to provide an improved analog voltmeter with a display capable of simultaneously indicating the value of a measured signal and its relation to predetermined limits.
It is another object of the :invention to provide a variable colour analog display voltrneter.
It is further object of the invention to provide a variable colour moving dot type analog voltmeter of extremely simple construction.
In summary, an analog voltmeter of this invention includes a device for measuring an input signal and a variable colour analog display for providing an analog indication of the signal. Limit colour control is provided for indicating measurement limits on the display. The colour of the analog indication of the input signal is controlled in accordance with the relation of the signal to the limits.
Further objects of the invention will become obvious from the accompanying drawings and their description.
~.~5~9()~3 BRIEF DESCRIPTION OF THE DRAWINGS
In tl~e drawings in which is shown the preferred embodiment of the inventio~, FIGS. la to le are examples of a variable colour bar graph display on which measured values and limits are simultaneously indicated.
FIG. 2 is a block diagram of a variable colour analog display voltmeter.
FIG. 3 is a simplified schematic diagram of a variable colour moving dot type voltmeter.
FIG. 4 is a cross-sectional view, taken along the line
illuminated, without simultaneously indicating the limits.
When the measured value exceeds the limits, the portion of the band below the low limit is fully illuminated, the portion of the band between the limits is flashed on and off, to attract attention of an operator, and the portion of the band above the high limit is extinguished, to indicate the limit points, without simultaneously indicating the actual measured value.
Such a concept is not usable in a moving dot type display voltmeter wherein the value of measured voltage is indicated by the position of a single illuminated LED, because it is impossible to simultaneously fully illuminate the single LED, flash it on and off, and extinguish it.
~ ~ ~7130 S~MMARY OF THE INVENTION
Accordingly, it is the principal object of this invention to provide an improved analog voltmeter with a display capable of simultaneously indicating the value of a measured signal and its relation to predetermined limits.
It is another object of the :invention to provide a variable colour analog display voltrneter.
It is further object of the invention to provide a variable colour moving dot type analog voltmeter of extremely simple construction.
In summary, an analog voltmeter of this invention includes a device for measuring an input signal and a variable colour analog display for providing an analog indication of the signal. Limit colour control is provided for indicating measurement limits on the display. The colour of the analog indication of the input signal is controlled in accordance with the relation of the signal to the limits.
Further objects of the invention will become obvious from the accompanying drawings and their description.
~.~5~9()~3 BRIEF DESCRIPTION OF THE DRAWINGS
In tl~e drawings in which is shown the preferred embodiment of the inventio~, FIGS. la to le are examples of a variable colour bar graph display on which measured values and limits are simultaneously indicated.
FIG. 2 is a block diagram of a variable colour analog display voltmeter.
FIG. 3 is a simplified schematic diagram of a variable colour moving dot type voltmeter.
FIG. 4 is a cross-sectional view, taken along the line
4-4 in FIG. le, revealing internal structure of a portion of variable colour bar graph display device.
Throughout the drawings, like characters indicate like parts.
~L25~9~ 3 DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now, more particularly, to the drawings, in FIGS. la to le are shown examples of a variable colour bar graph display on which are indicated five different combinations of a measured value and limits. Considering the full scale to be 10 VoLts, each display element in bar graph display 11 represents 1 Volt step. Thus display element la represents 1 Volt, display element lb represents 2 Volts, display element lc represents 3 Volts, etc. It 10 would be obvious that the illustrated display may represent other scales of other quantities.
By referring to several illustrated examples, FIG. la simultaneously e~hibits acceptable measurement field from low limit 4 Volts to high limit 7 Volts, by illuminating display elements ld, le, lf, and lg in green colour, and measured value 1 Volt (below the low limit), by illuminating display element la in red colour. The rernaining display elements lb, lc, lh, li, and lj are extinguished. The red colour of the measured value indicates that it does not lie 20 within the limits.
FIG. lb exhibits the same limits and measured value 9 Volts ~above the high limit), by illuminating display element li in red colour, to indicate that the measured value does not lie within the limits.
FIG. lc exhibits the same limits and measured value 5 Volts, by illuminating display element le in yellow colour, to indicate that the measured value lies within the bounds of the limits.
FIG. ld exhib:its only a low measurement limit 8 Volts ~ '3~ .3 (thereby indicating that all higher values are acceptable), by i'lluminating display elements lh, li, and lj in green colour, and measured value 4 Volts, by illuminating display element l.d in red colour, to indicate that the measured value is not acceptable (not higher that the low limit).
FIG. le exhi.bits only a high measurement limit 3 Volts (thereby indicating that all lower values are accepta'ble), by il].uminating display elements la and lc in green colour, and measured value 2 Volts, by illuminating display element 10 lb in yellow colour, to indicate that the measured value is acceptable (lower that the high limit).
In FIG. 2 is shown a block diagram of a varia'ble colour analog voltmeter of the invention which includes an analog comparator 14, for comparing input signal Vin with reference values, and a display driver 15, for causing an analog indication of the input signal to be exhibited on a variable colour analog display 10, in a manner well understood by those skilled in the art. The invention resides i.n the addition of a limit colour control 13, for causing 20 measurement limits to be exhi'bited on the display 10 in a desired colour, and a value colour control 12, for controlling the colour of the exhibited analog indication in accordance with its relation to the limits. The analog voltmeter of the invention is thus capable of simultaneously exhibiting measured value, by analog indication, and its relation to predetermined limits, by colour.
Proceeding now to the detailed description, in FIG. 3 is shown a simplified schematic diagram of a variable colour bar graph voltmeter of the invention. The circuit employs a 30 commercially available dot display driver 16 which contains ~ 3()~3 a string of voltage comparators combined with a voltage reference network for detecting the level of an input signal Vin, app]ied to its input SIG IN, and for accordingly developing output drive signals to illuminate the appropriate display element for providing a linear analog indication of the level of the input signal. The voltmeter operates in a moving dot mode, ~hich is achieved 'oy leaving its MODE input open. The value of resistor 9n coupled to reference output pin REF OUT determines the LED current and therefore the brightness of the display.
Each display element of bar graph display device ll includes a pair of closely adjacent LEDs (light emitting diodes): a red LED 2 and green LED 3 which are adapted for producing a composite light signal of a variable colour.
The cathodes of all red LEDs 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, 2i, and 2j are respectively coupled to the outputs IED l, LED 2, LED 3, LED 4, LED 5, LED 6, LED 7, LED 8, LED 9, and LED lO of dot display driver 16. The cathodes of all green LEDs 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, and 3j are respectively coupled, via current limiting resistors 9a, 9b, 9c, 9d, 9e, 9f, 9g, and 9h, to the outputs QO, Ql, Q2, Q3, Q4, Q5, Q6, and Q7 of an 8-bit latch l9a and, via current limiting resistors 9i and 9j, to the outputs QO and Ql of a 2-bit latch l9b. The anodes of all red LEDs 2a to 2j and all green LEDs 3a to 3j are commonly coupled to a power source +VCC. Data representing predetermined low and high measurement l:;mits, defining the acceptable measurement field, may be stored in latches l9a, l9b by presenting the data to their inputs DO to D7 and by activating their latching inputs (not shown).
~ 7~)Y~
The operation of the analog voltmeter wil.l be explained on several examples. EXAMPLE la considers low measurement limit 4 Volts and high measurement limit 7 Volts. Data representing such limits may be stored in latches 19a, 19b by applying a low logic level to inputs D3, D4, D5, and D6 of latch l9a, and by applying a high logic level to all remaining inputs D0, Dl, D2, D7 of latch l9a and D0, Dl of latch l9b, and by activating latching inputs. As a result, outputs Q3, Q4, Q5, and Q6 drop to a low logic level. The current flows from the source +VCC, via green LED 3d and current ].imiting resistor 9d to output Q3, via green LED 3e and resistor 9e to output Q4, via green LED 3f and resistor 9f to output Q5, and via green LED 3g and resistor 9g to output Q6. As R consequence, green LEDs 3d7 3e, 3f, and 3g illuminateO The remaining green LEDs are extinguished because the remaining outputs of the latches are at a high logic level. Considering the measured va].ue of the input signal to be about 1 Volt, dot display driver 16 develops a low level at its output LED 1. The current flows from the source +VCC via red LED 2a to the output LED 1. As a result, red LED 2a illuminates. The overall effect is that display elements ld, le, lf, and lg illuminate in green colour, to indicate accep-table measurement field from 4 Volts to 7 Volts, and display element la illuminates in red colour, to simultaneously indicate measured value of the input signal (about 1 Volt), by position, and its relation to the limits, by red colour (meaning that it does not lie within the bounds of the limits), as viewed in FIG. la.
EXAMPLE lb considers the same measurement limits and measured value about 9 Volts. Dot display driver 16 develops ~579~3'3 in such case a low level at lts output LED 9. The current flows from the source +VCC via red LED 2i to the output LED
9 to cause red LED 2i to illuminate. The overall effect is that display elements ld, le, lf, and lg illuminate in green colour, to indicate acceptable measurement field from 4 Volts to 7 Volts, and display element li illuminates in red colour, to indicate that the measured value 9 Volts does not lie within the bounds of the limits, as viewed in FIG. lb.
EX~MPLE lc considers the same measurement limits and measured value about 5 Volts. Dot clisplay driver 16 develops in such case a low level at its output LED 5. The current flows from the source ~VCC via red LED 2e to the output LED
Throughout the drawings, like characters indicate like parts.
~L25~9~ 3 DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now, more particularly, to the drawings, in FIGS. la to le are shown examples of a variable colour bar graph display on which are indicated five different combinations of a measured value and limits. Considering the full scale to be 10 VoLts, each display element in bar graph display 11 represents 1 Volt step. Thus display element la represents 1 Volt, display element lb represents 2 Volts, display element lc represents 3 Volts, etc. It 10 would be obvious that the illustrated display may represent other scales of other quantities.
By referring to several illustrated examples, FIG. la simultaneously e~hibits acceptable measurement field from low limit 4 Volts to high limit 7 Volts, by illuminating display elements ld, le, lf, and lg in green colour, and measured value 1 Volt (below the low limit), by illuminating display element la in red colour. The rernaining display elements lb, lc, lh, li, and lj are extinguished. The red colour of the measured value indicates that it does not lie 20 within the limits.
FIG. lb exhibits the same limits and measured value 9 Volts ~above the high limit), by illuminating display element li in red colour, to indicate that the measured value does not lie within the limits.
FIG. lc exhibits the same limits and measured value 5 Volts, by illuminating display element le in yellow colour, to indicate that the measured value lies within the bounds of the limits.
FIG. ld exhib:its only a low measurement limit 8 Volts ~ '3~ .3 (thereby indicating that all higher values are acceptable), by i'lluminating display elements lh, li, and lj in green colour, and measured value 4 Volts, by illuminating display element l.d in red colour, to indicate that the measured value is not acceptable (not higher that the low limit).
FIG. le exhi.bits only a high measurement limit 3 Volts (thereby indicating that all lower values are accepta'ble), by il].uminating display elements la and lc in green colour, and measured value 2 Volts, by illuminating display element 10 lb in yellow colour, to indicate that the measured value is acceptable (lower that the high limit).
In FIG. 2 is shown a block diagram of a varia'ble colour analog voltmeter of the invention which includes an analog comparator 14, for comparing input signal Vin with reference values, and a display driver 15, for causing an analog indication of the input signal to be exhibited on a variable colour analog display 10, in a manner well understood by those skilled in the art. The invention resides i.n the addition of a limit colour control 13, for causing 20 measurement limits to be exhi'bited on the display 10 in a desired colour, and a value colour control 12, for controlling the colour of the exhibited analog indication in accordance with its relation to the limits. The analog voltmeter of the invention is thus capable of simultaneously exhibiting measured value, by analog indication, and its relation to predetermined limits, by colour.
Proceeding now to the detailed description, in FIG. 3 is shown a simplified schematic diagram of a variable colour bar graph voltmeter of the invention. The circuit employs a 30 commercially available dot display driver 16 which contains ~ 3()~3 a string of voltage comparators combined with a voltage reference network for detecting the level of an input signal Vin, app]ied to its input SIG IN, and for accordingly developing output drive signals to illuminate the appropriate display element for providing a linear analog indication of the level of the input signal. The voltmeter operates in a moving dot mode, ~hich is achieved 'oy leaving its MODE input open. The value of resistor 9n coupled to reference output pin REF OUT determines the LED current and therefore the brightness of the display.
Each display element of bar graph display device ll includes a pair of closely adjacent LEDs (light emitting diodes): a red LED 2 and green LED 3 which are adapted for producing a composite light signal of a variable colour.
The cathodes of all red LEDs 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, 2i, and 2j are respectively coupled to the outputs IED l, LED 2, LED 3, LED 4, LED 5, LED 6, LED 7, LED 8, LED 9, and LED lO of dot display driver 16. The cathodes of all green LEDs 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, and 3j are respectively coupled, via current limiting resistors 9a, 9b, 9c, 9d, 9e, 9f, 9g, and 9h, to the outputs QO, Ql, Q2, Q3, Q4, Q5, Q6, and Q7 of an 8-bit latch l9a and, via current limiting resistors 9i and 9j, to the outputs QO and Ql of a 2-bit latch l9b. The anodes of all red LEDs 2a to 2j and all green LEDs 3a to 3j are commonly coupled to a power source +VCC. Data representing predetermined low and high measurement l:;mits, defining the acceptable measurement field, may be stored in latches l9a, l9b by presenting the data to their inputs DO to D7 and by activating their latching inputs (not shown).
~ 7~)Y~
The operation of the analog voltmeter wil.l be explained on several examples. EXAMPLE la considers low measurement limit 4 Volts and high measurement limit 7 Volts. Data representing such limits may be stored in latches 19a, 19b by applying a low logic level to inputs D3, D4, D5, and D6 of latch l9a, and by applying a high logic level to all remaining inputs D0, Dl, D2, D7 of latch l9a and D0, Dl of latch l9b, and by activating latching inputs. As a result, outputs Q3, Q4, Q5, and Q6 drop to a low logic level. The current flows from the source +VCC, via green LED 3d and current ].imiting resistor 9d to output Q3, via green LED 3e and resistor 9e to output Q4, via green LED 3f and resistor 9f to output Q5, and via green LED 3g and resistor 9g to output Q6. As R consequence, green LEDs 3d7 3e, 3f, and 3g illuminateO The remaining green LEDs are extinguished because the remaining outputs of the latches are at a high logic level. Considering the measured va].ue of the input signal to be about 1 Volt, dot display driver 16 develops a low level at its output LED 1. The current flows from the source +VCC via red LED 2a to the output LED 1. As a result, red LED 2a illuminates. The overall effect is that display elements ld, le, lf, and lg illuminate in green colour, to indicate accep-table measurement field from 4 Volts to 7 Volts, and display element la illuminates in red colour, to simultaneously indicate measured value of the input signal (about 1 Volt), by position, and its relation to the limits, by red colour (meaning that it does not lie within the bounds of the limits), as viewed in FIG. la.
EXAMPLE lb considers the same measurement limits and measured value about 9 Volts. Dot display driver 16 develops ~579~3'3 in such case a low level at lts output LED 9. The current flows from the source +VCC via red LED 2i to the output LED
9 to cause red LED 2i to illuminate. The overall effect is that display elements ld, le, lf, and lg illuminate in green colour, to indicate acceptable measurement field from 4 Volts to 7 Volts, and display element li illuminates in red colour, to indicate that the measured value 9 Volts does not lie within the bounds of the limits, as viewed in FIG. lb.
EX~MPLE lc considers the same measurement limits and measured value about 5 Volts. Dot clisplay driver 16 develops in such case a low level at its output LED 5. The current flows from the source ~VCC via red LED 2e to the output LED
5 to cause red LED 2e to illuminate. As a result of internal blending of light signals emitted by green LED 3e and red LED 2e, the display element le illuminates in substantially yellow colourO The overall effect is that display elements ld, lf, and lg illuminate in green colour, to indicate acceptable measurement field from 4 Volts to 7 Volts, and display element le illuminates in yellow colour, to indicate that the measured value 5 Volts lies within the bounds of the limits, as viewed in FIG. lc.
E~MPLE ld considers only a low measurement limit 8 Volts, thereby indicating that all higher measured values are acceptable. Data representing such limit stored in latches l9a, l9b cause outputs Q7 of latch l9a and Q0, Ql of latch l9b to drop to a low logic level. The current flows from the source +VCC, via green LED 3h and resistor 9h to output Q7 of latch l9a, via green LED 3i and resistor 9i to output Q0 of latch l9b, and via green LED 3j and resistor 9j to output Ql of latch l9b. As a consequence, green LEDs 3h, ~ 3 3i, and 3j illuminate. The remaining green LEDs are extinguished because the remaining outputs of ]atch l9a are at a high logic level. Considering the measured value to be about 4 Volt, dot display driver 16 develops a low level at its output LED 4. The current flows from the source +VCC via red LED 2d to the output LED 4 to cause red LED 2d to illuminate. The overall effect is that display elements lh, li, and lj illuminate in green colour, to indicate acceptable measurement field from 8 Volts to 10 Volts, and display element ld illuminates in red colour, to indicate that the measured value 4 Volts does not lie within the acceptable field, as viewed in FIG. ld.
EXAMPLE le considers only high measurement limit 3 Volts, thereby indicating that all lower measured values are acceptable. Data representing such limit stored in latches l9a, l9b cause outputs Q0, Q1, and Q2 of latch 19a to drop to a low logic level. The current flows from the source +VCC, via green LED 3a and resistor 9a to output Q0, via green LED 3b and resistor 9b to output Q19 and via green LED
3c and resistor 9c to output Q2. As a consequence, green LEDs 3a, 3b, and 3c illuminate. The remaining green LEDs are extinguished because the remaining outputs of the latches are at a high logic level. Considering the measured value to be about 2 Volts, dot display driver 16 develops a low level at its output LED 2. The current flows from the source +VCC via red LED 2b to the output LED 2 to cause red LED 2b to illuminate. As a result of internal blending of light signals emitted by green LED 3b and red LED 2b, the display element lb illuminates in substantially yellow colour. The overall effect is that display elemen~s la and ~ 3~)~3 lc illuminate in green colour, to indicate acceptable measurement field from 1 Volt to 3 Volts, and display element lb illuminates in yellow colour, to indicate that the measured value 2 Volts lies within the acceptable field, as viewed in FIG. le.
The colour of the composite light signal may be adjusted by changing the value of resistor 9n in relation to the values of current limiting resistors 9a to 9j.
An important consideration has been given to physical arr~ngement of the light emitting diodes in the display elements, as illustrated in FIG. 4. In the display element lj, red LED 2j and green LED 3j are disposed on a support 4 in a light blending cavity 5j and are completely surrounded by transparent light scattering material 6. When forwardly biased, the LEDs 2j and 3j emit light signals of red and green colours, respectively, which are blended by passing through light scattering material 6, acting to disperse the light signals, to form a composite light signal that emerges at the upper surface of the display element lj. The colour of the composite light signal may be controlled by varying the portions of red and green light signals. In the display element li, red LED 2i and green LED 3i are similarly disposed in a light blending cavity 5i and may be similarly activated. In a similar fashion, red LED 2h and green LED
3h are disposed in a light blending cavity 5h, and red LED
2g and green LED 3g are disposed in a light blending cavity 5g.
The display elements lj to lg are optically separated from one another by opaque walls 7. Although not shown~ it will be appreciated that the remaining display elements are ~ ~ ~7 ~ 3 similarly optically separated. In the display element lj, the walls 7a and 7b have generally smooth inclined surfaces 8a and 8b defining an obtuse angle with the support 4 and deEi.ning a light blending cavity 5j therebetween. In the display element li, the inclined surfaces 8c and 8d of the walls 7b and 7c similarly define a light blending cavity 5i therebetween. In a slmilar fashion, the light blending cavity 5h is defined by inclined surfaces 8e and 8f of the walls 7c and 7d, and light blending cavity 5g is defined by inclined surfaces 8g and 8h of the walls 7d and 7e.
Although the walls and light blending cavities are shown to be of certain shapes and dimensions, it is envisi.oned that they may be modified and rearranged.
The invention may be now briefly summarized. The method was disclosed of simultaneously indicating a measured value and its relation to a predetermined limit, on a single variable colour analog display, by causing an analog indication of the measured value to be exhibited on the display and by controlling the colour of the indication in accordance with the relation of the measured value to the limit.
A variable colour analog voltmeter was disclosed that comprises a signal measuring device, variable colour analog display for providing an analog indication of the signal, and colour control for controlling the colour of the analog indication in accordance with the relation of the measured signal to a low and high predetermined limits. The field between the limits may be also exhibited on the display in a different colour.
It would be obvious that persons skilled in the art may ~57~ 3 resort to modifications in the construction of the preferred embodiment shown herein, without departing from the spirit of the invention as defined in the appended claims. It is contemplated that the principles of the invention may be also applied to numerous diverse types of display devices, such are liquid crystal, plasma devices, and the like.
~ 5~ .3 CORRELATION TABLE
This is a correlation table of reference characters, their descriptions, and examples of commercially available parts.
DESCRIPTION EXAMPLE
1 display element 2 red LED
3 green L,ED
4 support light blending cavity
E~MPLE ld considers only a low measurement limit 8 Volts, thereby indicating that all higher measured values are acceptable. Data representing such limit stored in latches l9a, l9b cause outputs Q7 of latch l9a and Q0, Ql of latch l9b to drop to a low logic level. The current flows from the source +VCC, via green LED 3h and resistor 9h to output Q7 of latch l9a, via green LED 3i and resistor 9i to output Q0 of latch l9b, and via green LED 3j and resistor 9j to output Ql of latch l9b. As a consequence, green LEDs 3h, ~ 3 3i, and 3j illuminate. The remaining green LEDs are extinguished because the remaining outputs of ]atch l9a are at a high logic level. Considering the measured value to be about 4 Volt, dot display driver 16 develops a low level at its output LED 4. The current flows from the source +VCC via red LED 2d to the output LED 4 to cause red LED 2d to illuminate. The overall effect is that display elements lh, li, and lj illuminate in green colour, to indicate acceptable measurement field from 8 Volts to 10 Volts, and display element ld illuminates in red colour, to indicate that the measured value 4 Volts does not lie within the acceptable field, as viewed in FIG. ld.
EXAMPLE le considers only high measurement limit 3 Volts, thereby indicating that all lower measured values are acceptable. Data representing such limit stored in latches l9a, l9b cause outputs Q0, Q1, and Q2 of latch 19a to drop to a low logic level. The current flows from the source +VCC, via green LED 3a and resistor 9a to output Q0, via green LED 3b and resistor 9b to output Q19 and via green LED
3c and resistor 9c to output Q2. As a consequence, green LEDs 3a, 3b, and 3c illuminate. The remaining green LEDs are extinguished because the remaining outputs of the latches are at a high logic level. Considering the measured value to be about 2 Volts, dot display driver 16 develops a low level at its output LED 2. The current flows from the source +VCC via red LED 2b to the output LED 2 to cause red LED 2b to illuminate. As a result of internal blending of light signals emitted by green LED 3b and red LED 2b, the display element lb illuminates in substantially yellow colour. The overall effect is that display elemen~s la and ~ 3~)~3 lc illuminate in green colour, to indicate acceptable measurement field from 1 Volt to 3 Volts, and display element lb illuminates in yellow colour, to indicate that the measured value 2 Volts lies within the acceptable field, as viewed in FIG. le.
The colour of the composite light signal may be adjusted by changing the value of resistor 9n in relation to the values of current limiting resistors 9a to 9j.
An important consideration has been given to physical arr~ngement of the light emitting diodes in the display elements, as illustrated in FIG. 4. In the display element lj, red LED 2j and green LED 3j are disposed on a support 4 in a light blending cavity 5j and are completely surrounded by transparent light scattering material 6. When forwardly biased, the LEDs 2j and 3j emit light signals of red and green colours, respectively, which are blended by passing through light scattering material 6, acting to disperse the light signals, to form a composite light signal that emerges at the upper surface of the display element lj. The colour of the composite light signal may be controlled by varying the portions of red and green light signals. In the display element li, red LED 2i and green LED 3i are similarly disposed in a light blending cavity 5i and may be similarly activated. In a similar fashion, red LED 2h and green LED
3h are disposed in a light blending cavity 5h, and red LED
2g and green LED 3g are disposed in a light blending cavity 5g.
The display elements lj to lg are optically separated from one another by opaque walls 7. Although not shown~ it will be appreciated that the remaining display elements are ~ ~ ~7 ~ 3 similarly optically separated. In the display element lj, the walls 7a and 7b have generally smooth inclined surfaces 8a and 8b defining an obtuse angle with the support 4 and deEi.ning a light blending cavity 5j therebetween. In the display element li, the inclined surfaces 8c and 8d of the walls 7b and 7c similarly define a light blending cavity 5i therebetween. In a slmilar fashion, the light blending cavity 5h is defined by inclined surfaces 8e and 8f of the walls 7c and 7d, and light blending cavity 5g is defined by inclined surfaces 8g and 8h of the walls 7d and 7e.
Although the walls and light blending cavities are shown to be of certain shapes and dimensions, it is envisi.oned that they may be modified and rearranged.
The invention may be now briefly summarized. The method was disclosed of simultaneously indicating a measured value and its relation to a predetermined limit, on a single variable colour analog display, by causing an analog indication of the measured value to be exhibited on the display and by controlling the colour of the indication in accordance with the relation of the measured value to the limit.
A variable colour analog voltmeter was disclosed that comprises a signal measuring device, variable colour analog display for providing an analog indication of the signal, and colour control for controlling the colour of the analog indication in accordance with the relation of the measured signal to a low and high predetermined limits. The field between the limits may be also exhibited on the display in a different colour.
It would be obvious that persons skilled in the art may ~57~ 3 resort to modifications in the construction of the preferred embodiment shown herein, without departing from the spirit of the invention as defined in the appended claims. It is contemplated that the principles of the invention may be also applied to numerous diverse types of display devices, such are liquid crystal, plasma devices, and the like.
~ 5~ .3 CORRELATION TABLE
This is a correlation table of reference characters, their descriptions, and examples of commercially available parts.
DESCRIPTION EXAMPLE
1 display element 2 red LED
3 green L,ED
4 support light blending cavity
6 light scattering material
7 opaque wall
8 inclined surface of wall
9 resistor
10 variable colour analog display
11 variable colour bar graph display
12 value colour control
13 limi.t colour control
14 analog comparator
15 display driver
16 dot display driver LM3914 19 8-bit latch 74F373
Claims (12)
1. A measuring device comprising:
signal measuring means;
analog display means including a plurality of side by side positioned variable colour display elements;
value control means for selectively illuminating a single one of said display elements corresponding by its position to a measured value of the signal; and colour control means for controlling the colour of the illuminated display element in accordance with the relation of said value of the signal to a predetermined limit.
signal measuring means;
analog display means including a plurality of side by side positioned variable colour display elements;
value control means for selectively illuminating a single one of said display elements corresponding by its position to a measured value of the signal; and colour control means for controlling the colour of the illuminated display element in accordance with the relation of said value of the signal to a predetermined limit.
2. A method of simultaneously indicating a measured value of a signal, a predetermined limit, and the relation of said value of the signal to said limit, on a single variable colour analog display means, by causing said limit to be exhibited on said display means in a first colour, and by causing an analog indication of said value of the signal to be exhibited on said display means either in a second or in a third colour in accordance with the relation of said value of the signal to said limit, said first, second, and third colours being respectively different.
3. A measuring device comprising:
signal measuring means;
variable colour analog display means for providing an analog indication of a measured value of the signal;
means for exhibiting a predetermined limit on said display means in a first colour; and colour control means for illuminating said analog indication either in a second or in a third colour in accordance with the relation of said value of the signal to said limit, said first, second, and third colours being respectively different.
signal measuring means;
variable colour analog display means for providing an analog indication of a measured value of the signal;
means for exhibiting a predetermined limit on said display means in a first colour; and colour control means for illuminating said analog indication either in a second or in a third colour in accordance with the relation of said value of the signal to said limit, said first, second, and third colours being respectively different.
4. A method of simultaneously indicating a measured value of a signal, a predetermined limit, and the relation of said value of the signal to said limit, on a single analog display means including a plurality of side by side positioned variable colour display elements, by illuminating in a first colour a single one of said display elements corresponding by its position to the value of said limit, and by illuminating either in a second or in a third colour a selective one of said display elements corresponding by its position to said value of the signal, in accordance with the relation of said value of the signal to said limit, said first, second, and third colours being respectively different.
5. A measuring device comprising:
signal measuring means;
analog display means including a plurality of side by side positioned variable colour display elements;
limit control means for selectively illuminating in a first colour a single one of said display elements corresponding by its position to the value of a predetermined limit; and value colour control means for selectively illuminating either in a second colour or in a third colour a single one of said display elements corresponding by its position to a measured value of the signal, in accordance with the relation of said value of the signal to said limit, said first, second, and third colours being respectively different.
signal measuring means;
analog display means including a plurality of side by side positioned variable colour display elements;
limit control means for selectively illuminating in a first colour a single one of said display elements corresponding by its position to the value of a predetermined limit; and value colour control means for selectively illuminating either in a second colour or in a third colour a single one of said display elements corresponding by its position to a measured value of the signal, in accordance with the relation of said value of the signal to said limit, said first, second, and third colours being respectively different.
6. A measuring device comprising:
signal measuring means;
variable colour analog display means for providing an analog indication of a measured value of the signal;
means for exhibiting predetermined low and high limits, defining an acceptable measurement field, on said display means in a first colour; and colour control means for illuminating said analog indication either in a second colour when said value of the signal does not lie within the bounds of said low and high limits or in a third colour when said value of the signal lies within the bounds of said low and high limits, said first, second, and third colours being respectively different.
signal measuring means;
variable colour analog display means for providing an analog indication of a measured value of the signal;
means for exhibiting predetermined low and high limits, defining an acceptable measurement field, on said display means in a first colour; and colour control means for illuminating said analog indication either in a second colour when said value of the signal does not lie within the bounds of said low and high limits or in a third colour when said value of the signal lies within the bounds of said low and high limits, said first, second, and third colours being respectively different.
7. A measuring device as defined in claim 6 wherein said third colour is obtained by blending said first and second colours.
8. A measuring device comprising:
signal measuring means;
analog display means including a plurality of side by side positioned variable colour display elements;
limit control means for selectively illuminating in a first colour a first one of said display elements, corresponding by its position to the value of a predetermined low limit, and a second one of said display elements, corresponding by its position to a predetermined high limit; and value colour control means for selectively illuminating a single one of said display elements corresponding by its position to a measured value of the signal either in a second colour when said value of the signal does not lie within the bounds of said low limit and said high limit or in a third colour when said value of the signal lies within the bounds of said low limit and said high limit, said first, second, and third colours being respectively different.
signal measuring means;
analog display means including a plurality of side by side positioned variable colour display elements;
limit control means for selectively illuminating in a first colour a first one of said display elements, corresponding by its position to the value of a predetermined low limit, and a second one of said display elements, corresponding by its position to a predetermined high limit; and value colour control means for selectively illuminating a single one of said display elements corresponding by its position to a measured value of the signal either in a second colour when said value of the signal does not lie within the bounds of said low limit and said high limit or in a third colour when said value of the signal lies within the bounds of said low limit and said high limit, said first, second, and third colours being respectively different.
9. A measuring device comprising:
signal measuring means;
variable colour analog display means for providing an analog indication of a measured value of the signal;
memory means for storing data representing the value of a limit, said memory means having a memory output indicative of the value of the stored data;
limit control means responsive to said memory output for selectively exhibiting the value of said limit on said display means in a first colour; and colour control means for illuminating said analog indication either in a second or in a third colour in accordance with the relation of said value of the signal to said limit, said first, second, and third colours being respectively different.
signal measuring means;
variable colour analog display means for providing an analog indication of a measured value of the signal;
memory means for storing data representing the value of a limit, said memory means having a memory output indicative of the value of the stored data;
limit control means responsive to said memory output for selectively exhibiting the value of said limit on said display means in a first colour; and colour control means for illuminating said analog indication either in a second or in a third colour in accordance with the relation of said value of the signal to said limit, said first, second, and third colours being respectively different.
10. A measuring device comprising:
signal measuring means;
variable colour analog display means for providing an analog indication of a measured value of the signal;
memory means for storing data representing a field between predetermined low and high limits, said memory means having memory outputs indicative of the values of the stored data;
limit control means responsive to said memory outputs for selectively exhibiting on said display means said field in a first colour; and colour control means for illuminating said analog indication either in a second or in a third colour in accordance with the relation of said value of the signal to said field, said first, second, and third colours being respectively different.
signal measuring means;
variable colour analog display means for providing an analog indication of a measured value of the signal;
memory means for storing data representing a field between predetermined low and high limits, said memory means having memory outputs indicative of the values of the stored data;
limit control means responsive to said memory outputs for selectively exhibiting on said display means said field in a first colour; and colour control means for illuminating said analog indication either in a second or in a third colour in accordance with the relation of said value of the signal to said field, said first, second, and third colours being respectively different.
11. A measuring device comprising:
signal measuring means;
analog display means including a plurality of side by side positioned variable colour display elements;
limit control means for selectively illuminating in a first colour certain of said display elements corresponding by their positions to a field between a predetermined low limit and a predetermined high limit; and value colour control means for selectively illuminating a single one of said display elements corresponding by its position to a measured value of the signal either in a second colour when said value of the signal does not lie within said field or in a third colour when said value of the signal lies within said field, said first, second, and third colours being respectively different.
signal measuring means;
analog display means including a plurality of side by side positioned variable colour display elements;
limit control means for selectively illuminating in a first colour certain of said display elements corresponding by their positions to a field between a predetermined low limit and a predetermined high limit; and value colour control means for selectively illuminating a single one of said display elements corresponding by its position to a measured value of the signal either in a second colour when said value of the signal does not lie within said field or in a third colour when said value of the signal lies within said field, said first, second, and third colours being respectively different.
12. A measuring device comprising:
signal measuring means;
analog display means including a plurality of variable colour display elements arranged in an array, each said display element including a first light source for emitting upon activation light signals of a first primary colour, second light source for emitting upon activation light signals of a second primary colour, and means for combining said light signals in each said display element to obtain a composite light signal of a composite colour;
value control means for providing on said display means an analog indication of a measured value of the signal by selectively activating a single one of said first light sources corresponding by a position in said array to said value of the signal, for illuminating it in said first primary colour;
memory means for storing data representing values of predetermined low and high limits;
limit control means responsive to said memory means for selectively activating certain of said second light sources corresponding by positions in said array to a field between said low and high limits, for illuminating said field in said second primary colour;
whereby said analog indication is illuminated either in said first primary colour when said value of the signal does not lie within the bounds of said low and high limits or in said composite colour when said value of the signal lies within the bounds of said low and high limits.
signal measuring means;
analog display means including a plurality of variable colour display elements arranged in an array, each said display element including a first light source for emitting upon activation light signals of a first primary colour, second light source for emitting upon activation light signals of a second primary colour, and means for combining said light signals in each said display element to obtain a composite light signal of a composite colour;
value control means for providing on said display means an analog indication of a measured value of the signal by selectively activating a single one of said first light sources corresponding by a position in said array to said value of the signal, for illuminating it in said first primary colour;
memory means for storing data representing values of predetermined low and high limits;
limit control means responsive to said memory means for selectively activating certain of said second light sources corresponding by positions in said array to a field between said low and high limits, for illuminating said field in said second primary colour;
whereby said analog indication is illuminated either in said first primary colour when said value of the signal does not lie within the bounds of said low and high limits or in said composite colour when said value of the signal lies within the bounds of said low and high limits.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/946,036 | 1986-12-24 | ||
| US06/946,036 US4812744A (en) | 1986-12-24 | 1986-12-24 | Variable color analog voltmeter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1257909A true CA1257909A (en) | 1989-07-25 |
Family
ID=25483862
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000553862A Expired CA1257909A (en) | 1986-12-24 | 1987-12-09 | Variable colour analog voltmeter |
Country Status (2)
| Country | Link |
|---|---|
| US (2) | US4812744A (en) |
| CA (1) | CA1257909A (en) |
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| US5066909A (en) * | 1990-01-30 | 1991-11-19 | Hewlett-Packard Company | Apparatus for testing an electronic circuit having an arbitrary output waveform |
| US5083456A (en) * | 1990-06-05 | 1992-01-28 | Colarelli Iii Nicholas J | Plate brake tester apparatus and method |
| US5230242A (en) * | 1990-06-05 | 1993-07-27 | Hunter Engineering Company | Plate brake tester apparatus and method |
| AU650865B2 (en) * | 1990-09-07 | 1994-07-07 | Caterpillar Inc. | Adaptive vehicle display |
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| EP0582622A4 (en) * | 1991-04-03 | 1996-03-06 | Magni Systems Inc | Adaptive graticule in a raster displayed waveform monitor |
| CA2071455A1 (en) * | 1991-10-16 | 1993-04-17 | Cary Lee Bates | Visually aging scroll bar |
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| US5369416A (en) * | 1992-06-17 | 1994-11-29 | Indikon Company, Inc. | Multi-color bargraph |
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| US5412312A (en) * | 1992-10-01 | 1995-05-02 | Snap-On Incorporated | Frequency and instantaneous voltage level meter |
| EP0631143A3 (en) * | 1993-06-28 | 1995-09-13 | Hitachi Electronics | Digital oscilloscope with flat panel colour display. |
| US5666129A (en) * | 1994-07-06 | 1997-09-09 | Level One Communications, Inc. | Electrical display elements for displaying multiple different conditions |
| US6216143B1 (en) | 1994-12-05 | 2001-04-10 | International Business Machines Corporation | Apparatus and method for generating animated color coded software traces |
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- 1986-12-24 US US06/946,036 patent/US4812744A/en not_active Expired - Lifetime
-
1987
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-
1988
- 1988-06-13 US US07/206,099 patent/US4868496A/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| US4868496A (en) | 1989-09-19 |
| US4812744A (en) | 1989-03-14 |
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