Method for continuously controlling color of display device

• US 6,310,590 B1
• Filed: 08/11/1999
• Issued: 10/30/2001
• Est. Priority Date: 01/15/1986
• Status: Expired due to Fees

• Current Assignee: Texas Digital Systems, Inc. (NCR Voyix Corporation)
• Original Assignee: Texas Digital Systems, Inc. (NCR Voyix Corporation)
• Inventors: Havel, Karel
• Primary Examiner(s): Jankus, Almis R.
• Assistant Examiner(s): AWAD, AMR A
• Application Number:
  US09/372,298
• Time in Patent Office: 811 Days
• Field of Search: 345/82, 345/83, 345/150, 345/87-104, 345/589, 345/593, 313/500, 313/501, 324/96, 324/115, 257/89, 257/90
• US Class Current: 345/83
• CPC Class Codes: G01R 13/02 for displaying measured electric variables in digital form
• CPC Class Codes: G01R 13/26 Circuits for controlling the intensity of the electron beam or the colour of the display
• CPC Class Codes: G01R 13/405 using a plurality of active, i.e. light emitting, e.g. electro-luminescent elements, i.e. bar graphs
• CPC Class Codes: G01R 15/125 for digital multimeters
• CPC Class Codes: G09G 3/14 Semiconductor devices, e.g. diodes

Abstract

A method for continuously controlling color of a display device comprises the steps of receiving three sets of data respectively representing the portions of three primary colors, accumulating three counts in accordance with the data, respectively, and setting three bistable devices for the respective durations of the accumulating. The outputs of the three bistable devices are coupled for respectively energizing three buses, to which the light emitting diodes of three primary colors are connected in accordance with their colors, for controlling the portions of the light signals of the primary colors emitted therefrom.

Claims

1. A method for continuously controlling color of a variable color display device, which includes a plurality of display areas arranged in a pattern for exhibiting, upon selective activation, a plurality of display units, each said display area including a first light emitting diode for emitting, when forwardly biased, light signals of a first primary color, a second light emitting diode for emitting, when forwardly biased, light signals of a second primary color, and means for combining said light signals in said display area to obtain a light signal of a composite color, the method comprising:

repeatedly defining a cycle by developing a start signal at the beginning of each said cycle;

receiving n-bit data representing in value the portions of a first primary color, where n is an integer having value at least 2;

developing an end signal timed, in relation to said start signal, in accordance with the value of said data;

activating a selective plurality of said display areas for exhibiting a selected display unit;

developing a stable signal of a first logic level in response to said start signal and a stable signal of an opposite logic level in response to said end signal;

applying a first control signal, in accordance with said stable signal of said first logic level, for forwardly biasing said first light emitting diodes in the activated display areas, and

applying a second control signal, in accordance with said stable signal of said opposite logic level, for forwardly biasing said second light emitting diodes in the activated display areas.

2. A method for continuously controlling color of a variable color display device, which includes a plurality of display areas arranged in a pattern for exhibiting, upon selective activation, a plurality of display units, each said display area including a first light emitting diode for emitting, when forwardly biased, light signals of a first primary color, a second light emitting diode for emitting, when forwardly biased, light signals of a second primary color, and means for combining said light signals in said display area to obtain a light signal of a composite color, the method comprising:

repeatedly defining a cycle by developing a start signal at the beginning of each said cycle;

receiving n-bit data representing in value the portions of a first primary color, where n is an integer having value at least 2;

developing an end signal timed, in relation to said start signal, in accordance with the value of said data;

activating a selective plurality of said display areas for exhibiting a selected display unit;

developing a true output and a complementary output, said true output being set in response to said start signal and reset in response to said end signal, and said complementary output being in the opposite condition;

applying a first control signal, in accordance with said true output, for forwardly biasing said first light emitting diodes in the activated display areas; and

applying a second control signal, in accordance with said complementary output, for forwardly biasing said second light emitting diodes in the activated display areas.

3. A method for continuously controlling color of a variable color display device, which includes a plurality of display areas arranged in a pattern for exhibiting, upon selective activation, a plurality of display units, each said display area including a first light emitting diode for emitting, when forwardly biased, light signals of a first primary color, a second light emitting diode for emitting, when forwardly biased, light signals of a second primary color, and means for combining said light signals in said display area to obtain a light signal of a composite color, the method comprising:

repeatedly developing a first start signal and a second start signal;

receiving first n-bit data representing in value the portions of a first primary color and second n-bit data representing in value the portions of a second primary color, where n is an integer having value at least 2;

developing a first end signal timed, in relation to said first start signal, in accordance with the value of said first n-bit data;

developing a second end signal timed, in relation to said second start signal, in accordance with the value of said second n-bit data;

activating a selective plurality of said display areas for exhibiting a selected display unit;

developing a first stable signal of a first logic level in response to said first start signal and another signal in response to said first end signal;

developing a second stable signal of a first logic level in response to said second start signal and another signal in response to said second end signal;

applying a first control signal, in accordance with said first stable signal of said first logic level, for forwardly biasing said first light emitting diodes in the activated display areas, and

applying a second control signal, in accordance with said second stable signal of said first logic level, for forwardly biasing said second light emitting diodes in the activated display areas.

4. A method for continuously controlling color of a variable color display device, which includes a plurality of display areas arranged in a pattern for exhibiting, upon selective activation, a plurality of display units, each said display area including a first light emitting diode for emitting, when forwardly biased, light signals of a first primary color, a second light emitting diode for emitting, when forwardly biased, light signals of a second primary color, and means for combining said light signals in said display area to obtain a light signal of a composite color, the method comprising:

repeatedly defining a cycle by developing a start signal at the beginning of each said cycle;

receiving n-bit data representing in value the portions of a first primary color, where n is an integer having value at least 2;

accumulating, in response to said start signal, a count proportional to the value of said data, and developing, when the count is accumulated, an end of count signal;

activating a selective plurality of said display areas for exhibiting a selected display unit;

developing a stable signal of a first logic level in response to said start signal and a stable signal of an opposite logic level in response to said end of count signal;

applying a first control signal, in accordance with said signal of said first logic level, for forwardly biasing said first light emitting diodes in the activated display areas; and

applying a second control signal, in accordance with said signal of said opposite logic level, for forwardly biasing said second light emitting diodes in the activated display areas.

5. A method for continuously controlling color of a variable color display device, which includes a plurality of display areas arranged in a pattern for exhibiting, upon selective activation, a plurality of display units, each said display area including a first light emitting diode for emitting, when forwardly biased, light signals of a first primary color, a second light emitting diode for emitting, when forwardly biased, light signals of a second primary color, and means for combining said light signals in said display area to obtain a light signal of a composite color, the method comprising:

repeatedly defining a cycle by developing a start signal at the beginning of each said cycle;

receiving n-bit data representing in value the portions of a first primary color, where n is an integer having value at least 2;

accumulating, in response to said start signal, a count proportional to the value of said data, and developing, when the count is accumulated, an end of count signal;

activating a selective plurality of said display areas for exhibiting a selected display unit;

developing a true output and a complementary output, said true output being set in response to said start signal and reset in response to said end of count signal, and said complementary output being in the opposite condition;

applying a first control signal, in accordance with said true output, for forwardly biasing said first light emitting diodes in the activated display areas; and

applying a second control signal, in accordance with said complementary output, for forwardly biasing said second light emitting diodes in the activated display areas.

6. A method for continuously controlling color of a variable color display device, which includes a plurality of display areas arranged in a pattern for exhibiting, upon selective activation, a plurality of display units, each said display area including a first light emitting diode for emitting, when forwardly biased, light signals of a first primary color, a second light emitting diode for emitting, when forwardly biased, light signals of a second primary color, and means for combining said light signals in said display area to obtain a light signal of a composite color, the method comprising:

repeatedly developing a first start signal and a second start signal;

receiving first n-bit data representing in value the portions of a first primary color and second n-bit data representing in value the portions of a second primary color, where n is an integer having value at least 2;

accumulating, in response to said first start signal, a count proportional to the value of said first n-bit data, and developing, when the count is accumulated, a first end of count signal;

accumulating, in response to said second start signal, a count proportional to the value of said second n-bit data, and developing, when the count is accumulated, a second end of count signal;

activating a selective plurality of said display areas for exhibiting a selected display unit;

developing a first stable signal of a first logic level in response to said first start signal and another signal in response to said first end of count signal;

developing a second stable signal of a first logic level in response to said second start signal and another signal in response to said second end of count signal;

applying a first control signal, in accordance with said first stable signal of said first logic level, for forwardly biasing said first light emitting diodes in the activated display areas; and

applying a second control signal, in accordance with said second stable signal of said first logic level, for forwardly biasing said second light emitting diodes in the activated display areas.

7. A method for controlling color of a variable color display device, which includes a plurality of display areas arranged in a pattern for exhibiting, upon selective activation, a plurality of display units, each said display area including a first light emitting diode for emitting, when forwardly biased, light signals of a first primary color, a second light emitting diode for emitting, when forwardly biased, light signals of a second primary color, means for combining said light signals in said display area to obtain a light signal of a composite color, each said light emitting diode including a first terminal and a second terminal, all said first terminals being of the same polarity, and all said second terminals being of the same polarity, opposite of the polarity of said first terminals, means for decoding including a decoder input and a plurality of decoder outputs coupled to said first terminals of said light emitting diodes in accordance with their positions in said pattern, a first bus to which said second terminals of all said first light emitting diodes are commonly coupled, and a second bus to which said second terminals of all said second light emitting diodes are commonly coupled, the method comprising:

repeatedly defining a cycle by developing a start signal at the beginning of each said cycle;

receiving n-bit data representing in value the portions of a first primary color, where n is an integer having value at least 2;

developing an end signal timed, in relation to said start signal, in accordance with the value of said data;

decoding, by receiving at said decoder input an input code defining a selected display unit, and by producing at said decoder outputs, in response to said input code, selective decoder output signals for selecting certain of said display areas;

developing a stable signal of a first logic level in response to said start signal and a stable signal of an opposite logic level in response to said end signal;

energizing said first bus, in accordance with said stable signal of said first logic level, for forwardly biasing certain ones of said first light emitting diodes, in accordance with said decoder output signals; and

energizing said second bus, in accordance with said stable signal of said opposite logic level, for forwardly biasing certain ones of said second light emitting diodes, in accordance with said decoder output signals.

8. A method for controlling color of a variable color display device, which includes a plurality of display areas arranged in a pattern for exhibiting, upon selective activation, a plurality of display units, each said display area including a first light emitting diode for emitting, when forwardly biased, light signals of a first primary color, a second light emitting diode for emitting, when forwardly biased, light signals of a second primary color, means for combining said light signals in said display area to obtain a light signal of a composite color, each said light emitting diode including a first terminal and a second terminal, all said first terminals being of the same polarity, and all said second terminals being of the same polarity, opposite of the polarity of said first terminals, means for decoding including a decoder input and a plurality of decoder outputs coupled to said first terminals of said light emitting diodes in accordance with their positions in said pattern, a first bus to which said second terminals of all said first light emitting diodes are commonly coupled, and a second bus to which said second terminals of all said second light emitting diodes are commonly coupled, the method comprising:

repeatedly defining a cycle by developing a start signal at the beginning of each said cycle;

receiving n-bit data representing in value the portions of a first primary color, where n is an integer having value at least 2;

developing an end signal timed, in relation to said start signal, in accordance with the value of said data;

decoding, by receiving at said decoder input an input code defining a selected display unit, and by producing at said decoder outputs, in response to said input code, selective decoder output signals for selecting certain of said display areas;

developing a true output and a complementary output, said true output being set in response to said start signal and reset in response to said end signal, and said complementary output being in the opposite condition;

coupling said true output for energizing said first bus, for forwardly biasing certain ones of said first light emitting diodes, in accordance with said decoder output signals; and

coupling said complementary output for energizing said second bus, for forwardly biasing certain ones of said second light emitting diodes, in accordance with said decoder output signals, when said complementary output is in its set condition.

9. A method for controlling color of a variable color display device, which includes a plurality of display areas arranged in a pattern for exhibiting, upon selective activation, a plurality of display units, each said display area including a first light emitting diode for emitting, when forwardly biased, light signals of a first primary color, a second light emitting diode for emitting, when forwardly biased, light signals of a second primary color, means for combining said light signals in said display area to obtain a light signal of a composite color, each said light emitting diode including a first terminal and a second terminal, all said first terminals being of the same polarity, and all said second terminals being of the same polarity, opposite of the polarity of said first terminals, means for decoding including a decoder input and a plurality of decoder outputs coupled to said first terminals of said light emitting diodes in accordance with their positions in said pattern, a first bus to which said second terminals of all said first light emitting diodes are commonly coupled, and a second bus to which said second terminals of all said second light emitting diodes are commonly coupled, the method comprising:

repeatedly developing a first start signal and a second start signal;

receiving first n-bit data representing in value the portions of a first primary color and second n-bit data representing in value the portions of a second primary color, where n is an integer having value at least 2;

developing a first end signal timed, in relation to said first start signal, in accordance with the value of said first n-bit data;

developing a second end signal timed, in relation to said second start signal, in accordance with the value of said second n-bit data;

decoding, by receiving at said decoder input an input code defining a selected display unit, and by producing at said decoder outputs, in response to said input code, selective decoder output signals for selecting certain of said display areas;

developing a first stable signal of a first logic level in response to said first start signal and another signal in response to said first end signal;

developing a second stable signal of a first logic level in response to said second start signal and another signal in response to said second end signal;

energizing said first bus, in accordance with said first stable signal of said first logic level, for forwardly biasing certain ones of said first light emitting diodes, in accordance with said decoder output signals; and

energizing said second bus, in accordance with said second stable signal of said first logic level, for forwardly biasing certain ones of said second light emitting diodes, in accordance with said decoder output signals.