Electronic display having segments wherein each segment is capable of selectively illuminating two colors

• US 4,488,149 A
• Filed: 02/26/1981
• Issued: 12/11/1984
• Est. Priority Date: 02/26/1981
• Status: Expired due to Fees

• Current Assignee: William A. Givens Jr
• Original Assignee: William A. Givens Jr
• Inventors: Givens, William A. Jr.
• Primary Examiner(s): Curtis, Marshall M.
• Application Number:
  US06/238,553
• Time in Patent Office: 1,384 Days
• Field of Search: 340/715, 340/762, 340/782, 340/701, 340/702, 340/703, 340/704
• US Class Current: 345/46
• CPC Class Codes: G09G 3/14 Semiconductor devices, e.g. diodes

Abstract

An electronic display including a first light emitting diode emitting a first color when biased in the forward direction, a second light emitting diode emitting a second color when biased in the forward direction, and means to selectively bias one of the first and the second light emitting diodes in the forward direction so the electronic display emits one of the first and the second colors.

Claims

1. An electronic display, comprising:

a segment, comprising;

a first light emitting diode having a cathode and an anode and emitting a first color when biased in the forward direction;

a second lignt emitting diode having a cathode and an anode and emitting a second color when biased in the forward direction, the cathode of the first light emitting diode being connected to the anode of the second light emitting diode and the anode of the first light emitting diode being connected to the cathode of the second light emitting diode;

means connected to the segment for selectively biasing one of the first and the second light emitting diodes in the forward direction, said means being connected to the common connection between the anode of the first light emitting diode and the cathode of the second light emitting diode and being connected to the common connection between the cathode of the first light emitting diode and the anode of the second light emitting diode, and said means selectively applying a bias to the common connection between the anode of the first light emitting diode and the cathode of the second light emitting diode and applying a negative bias to the common connection between the cathode of the first light emitting diode and the anode of the seocnd light emitting diode to bias the first light emitting diode in the forward direction, and said means selectively applying a positive bias to the common connection between the cathode of the first light emitting diode and the anode of the second light emitting diode and applying a negative bias to the common connection between the anode of the first light emitting diode and the cathode of the seocnd light emitting diode to bias the second light emitting diode in the forward direction;

a color control providing a color signal, the color control signal being connected to and applied at the common connection between the anode of the first light emitting diode and the cathode of the second light emitting diode; and

an inverting buffer receiving the color control signal and providing an inverted output signal, the inverted output signal being connected to and applied at the common connection between the cathode of the first light emitting diode and the anode of the second light emitting diode, the first light emitting diode being forward biased in the high state of the color control signal and the second light emitting diode being forward biased in the low state of the color control signal; and

wherein the means for selectively biasing one of the first and the second light emitting diodes is defined further to include;

a tri-state non-inverting buffer receiving the color control signal and providing an output signal connected to and received at the common connection between the anode of the first light emitting diode and the cathode of the second light emitting diode, the tri-state non-inverting buffer having a control input and providing a high impedance output signal in response to receiving a signal at the color control input in the low state and providing an output signal having the same state as the received signal in response to receiving a signal at the control input in the high state; and

wherein the means for selectively biasing the first and the second light emitting diodes is defined further as applying the signal to the control input of the tri-state non-inverting buffer.

2. An electronic display, comprising:

a plurality of segments arranged for displaying predetermined indicia, each segment comprising;

a first light emitting diode having a cathode and an anode and emitting a first color when biased in the forward direction; and

a second light emitting diode having a cathode and an anode and emitting a second color when biased in the forward direction, the cathode of the first light emitting diode being connected to the anode of the second light emitting diode and the anode of the first light emitting diode being connected to the cathode of the second light emitting diode; and

means connected to the segment for selectively biasing one of the first and the second light emitting diodes in the forward direction, said means selectively forward biasing a selected one of the first and the second light emitting diodes of selected ones of the segments for displaying predetermined indicia, said means comprising;

a four bit binary to seven segment decoder for receiving a four bit input binary code indicating a predetermined indicia, the decoder providing output signals in a predetermined state in response to receiving the four bit binary code;

a color control providing a color control signal;

a plurality of inverting buffers, each inverting buffer receiving the color control signal and providing an inverted output signal, the inverted output signal of each inverting buffer being connected to the common connection between the cathode of the first light emitting diode and the anode of the second light emitting diode of one of the segments; and

a plurality of tri-state non-inverting buffers, each non-inverting buffer receiving one of the output signals provided by the decoder at a control input and each non-inverting buffer providing an output signal having a high impedance in response to receiving a signal at the control input in the low state and each non-inverting buffer providing an output signal having the same state as a received input signal in response to receiving a signal in the high state at the control input, each non-inverting buffer receiving the color control signal and providing an output signal having the same state as the received color control signal when receiving a signal in the high state at the control input, the output signal of each non-inverting buffer being connected to and received at the common connection between the anode of the first light emitting diode and the cathode of the second light emitting diode of one of the segments.

3. An electronic display, comprising:

a plurality of segment arranged for displaying predetermined indicia, each segment comprising;

a first light emitting diode having a cathode and an anode and emitting a first color when biased in the forward direction; and

a second light emitting diode having a cathode and an anode and emitting a second color when biased in the forward direction, the cathode of the first light emitting diode being connected to the cathode of the second light emitting diode;

means connected to each segment for selectively forward biasing selected ones of the first and the second light emitting diodes of selected ones of the segments by applying a logic potential to the common connection between the cathodes of the first and the second light emitting diodes, said means comprising;

a four bit binary to seven segment decoder for receiving a four bit input binary code indicating a predetermined indicia, the decoder providing output signals in a predetermined state in response to receiving the four bit input binary code;

a color control providing a first color control signal and a second color control signal;

a plurality of AND gates, each AND gate receiving the first color control signal and one of the output signals provided by the decoder and providing an output signal in the high state in response to receiving the first color control signal in the high state and receiving the decoder output signal in the high state, the output signal provided by each AND gate being connected to the anode of the first light emitting diode of one of the segments; and

a plurality of AND gates, each AND gate receiving the second color control signal and one of the output signals provided by the decoder and providing an output signal in the high state in response to receiving the second color control signal in the high state and receiving the decoder output signal in the high state, the output signal provided by each AND gate being connected to the anode of the second light emitting diode of one of the segments.

4. An electronic display, comprising:

a plurality of segments arranged for displaying predetermined indicia, each segment comprising;

a first light emitting diode having a cathode and an anode and emitting a first color when biased in the forward direction; and

a second light emitting diode having a cathode and an anode and emitting a second color when biased in the forward direction, the cathode of the first light emitting diode being connected to the cathode of the second light emitting diode;

means connected to each of the segments for selectively biasing one of the first and the second light emitting diodes in the forward direction, the segments being arranged for displaying predetermined indicia by forward biasing a selected one of the first and the second light emitting diodes of selected ones of the segments, said means comprising;

a four bit binary to seven segment decoder for receiving a four bit input binary code indicating a predetermined indicia, the decoder providing output signals in a predetermined state in response to receiving the four bit input binary code;

a color control providing a second color control signal;

an inverter receiving the second color control signal and providing an inverted output signal, the inverted output signal being a first color control signal;

a plurality of AND gates, each AND gate receiving the first color control signal and one of the output signals provided by the decoder and providing an output signal in the high state in response to receiving the first color control signal in the high state and receiving the decoder output signal in the high state, the output signal provided by each AND gate being connected to the anode of the first light emitting diode of one of the segments; and

a plurality of AND gates, each AND gate receiving the first color control signal and one of the output signals provided by the decoder and providing an output signal in the high state in response to receiving the second color control signal in the high state and receiving the decoder output signal in the high state, the output signal provided by each AND gate being connected to the anode of the second light emitting diode of one of the segments.

5. An electronic display, comprising:

a plurality of segments arranged for displaying predetermined indicia, each segment comprising;

a first light emitting diode having a cathode and an anode and emitting a first color when biased in the forward direction; and

a second light emitting diode having a cathode and an anode and emitting a second color when biased in the forward direction, the anode of the first light emitting diode being connected to the anode of the second light emitting diode and the segments being arranged for displaying predetermined indicia by forward biasing a selected one of the first and the second light emitting diodes of selected ones of the segments;

means connected to each of the elements for selectively biasing one of the first and the second light emitting diodes in the forward direction, comprising;

a four bit binary to seven segment decoder for receiving a four bit input binary code indicating a predetermined indicia, the decoder providing output signals in a predetermined state in response to receiving the four bit input binary code;

a color control providing a first color control signal and a second color control signal;

a plurality of AND gates, each AND gate receiving the first color control signal and one of the output signals provided by the decoder and providing an output signal in the low state in response to receiving one of the first color control signals and the decoder output signal in the low state, the output signal provided by each AND gate being connected to the cathode of the first light emitting diode of one of the segments; and

a plurality of AND gates, and AND gate receiving the second color control signal and one of the output signals provided by the decoder and providing an output signal in the low state in response to receiving one of the second color control signals and the decoder output signal in the low state, the output signal provided by each AND gate being connected to the cathode of the second light emitting diode of one of the segments.

6. An electronic display, comprising:

a plurality of segments arranged for displaying predetermined indicia, each segment comprising;

a first light emitting diode having a cathode and an anode and emitting a first color when biased in the forward direction; and

a second light emitting diode having a cathode and an anode and emitting a second color when biased in the forward direction, the anode of the first light emitting diode being connected to the anode of the second light emitting diode; and

means connected to each of the segments for selectively biasing one of the first and the second light emitting diodes of selected ones of the segments by applying a logic high potential to the common connection between the anodes of the first and the second diodes, the segments being arranged for displaying a predetermined indicia by forward biasing selected ones of the first and the second light emitting diodes of selected ones of the segments, said means comprising;

a four bit binary to seven segment decoder for receiving a four bit input binary code indicating a predetermined indicia, the providing output signals in a predetermined state in response to receiving the four bit input binary code;

a color control providing a second color control signal;

an inverter receiving the second color control signal and providing an inverted output signal, the inverted output signal being a first color control signal;

a plurality of AND gates, each AND gate receiving the first color control signal and one of the output signals provided by the decoder and providing an output signal in the low state in response to receiving one of the first color control signals and the decoder output signal in the low state, the output signal provided by each AND gate being connected to the cathode of the first light emitting diode of one of the segments; and

a plurality of AND gates, each AND gate receiving the second color control signal and one of the output signals provided by the decoder and providing an output signal in the low state in response to receiving one of the second color control signals and the decoder output signal in the low state, the output signal provided by each AND gate being connected to the cathode of the second light emitting diode of one of the segments.

7. An electronic display, comprising:

a plurality of segments arranged for displaying predetermined indicia, comprising;

a first light emitting diode having a cathode and an anode and emitting a first color when biased in the forward direction; and

a second light emitting diode having a cathode and an anode and emitting a second color when biased in the forward direction, the segments being arranged for displaying predetermined indicia by forward biasing a selected one of the first and the second light emitting diodes of selected ones of the segments, the cathode of the first light emitting diode being connected to the anode of the second light emitting diode and the anode of the first light emitting diode being connected to the cathode of the second light emitting diode;

means connected to each of the segments for selectively biasing the first and the second light emitting diodes in the forward direction, comprising;

a four bit binary to seven segment decoder for receiving a four bit input binary code indicating a predetermined indicia, the decoder providing output signals in a predetermined state in response to receiving the four bit input binary code;

a color control providing a color control signal;

an inverting buffer receiving the color control signal and providing an inverted output signal, the inverted output signal being connected to the common connection between the cathode of the first light emitting diode and the anode of the second light emitting diode of each of the segments; and

a plurality of tri-state non-inverting buffers, each non-inverting buffer receiving one of the output signals provided by the decoder at a control input and each non-inverting buffer providing an output signal having a high impedance in response to receiving a signal at the control input in the low state and each non-inverting buffer providing an output signal having the same state as a received input signal in response to receiving a signal in the high state at the control input, each non-inverting buffer receiving the color control signal and providing an output signal having the same state as the received color control signal when receiving a signal in the high state at the control input, the output signal of each non-inverting buffer being connected to and received at the common connection between the anode of the first light emitting diode and the cathode of the second light emitting diode of one of the segments.