Control Apparatus

Abstract

Information is displayed on a color cathode ray tube in a color that contrasts with a background color. This information may be optionally obliterated by causing the information and background to be displayed in the same color. Logic circuitry combines information and color data to control display color.

Description

THE INVENTION

The present invention is generally concerned with electronics and more specifically concerned with color displays and even more particularly in color transposition of information signals.

While the prior art contains many types of character displays or information displays, there has always been a problem of quickly generating the information from a blank screen or making the information stand out so that it is easily noticed at a prescribed time. As will be realized, a changing condition attracts the eye much more readily than a steady state condition. The present invention, in a preferred embodiment, illustrates the principle of changing color which is believed to be one of the more significant changes of information as far as being noticed by the eye is concerned.

In operation, the present invention displays information on a screen, cathode ray tube, or other display in the same color as the background material. Upon command, this information is changed to a color different from the background so that it will be readily noticeable and may be acted upon. An additional feature is that the information may always be displayed and merely changed from one color to another both of which colors are different from the background for additional emphasis.

Many situations are evident for use of such a display. On roadside signs, for instance, there is the need of stored information which would not be useful to the motorist in most instances. However, in conditions of ice or snow it may be desirable to display this information so that he may act accordingly, it may also be desirable to have one color for a particular caution or bit of information and a different color for more urgent notice. An example would be "Accident Ahead" in yellow letters where the accident was not serious and did not seriously impede traffic. However, the letters could be changed to red if there were a serious accident and traffic were impeded or virtually stopped. Other examples will readily appear to the minds of those skilled in the art.

It is, therefore, an object of this invention to provide improved display apparatus.

Other objects and advantages of the present invention will be apparent after a reading of the specification and appended claims in conjunction with the drawings wherein:

FIG. 1 is a block schematic diagram of a simple embodiment of the invention;

FIG. 2 is a presentation of signal levels at various points within FIG. 1;

FIG. 3 is a presentation of a possible display; and

FIG. 4 is an illustration of the type of signal presentation used in the present invention.

DETAILED DESCRIPTION

In FIG. 1 a first NOR circuit N1 which is labeled 10 has inputs A1 and C1. An output 12 of NOR circuit 10 is supplied to a NOR circuit N3 which is designated as 14 and has an output 16 supplying signals to a gate 18. A further NOR circuit N2 which is labeled 20 has inputs A2 and C2. An output 22 from NOR circuit 20 supplies further input signals to NOR circuit 14. A fourth NOR circuit 24 has inputs A1 and C1 while a fifth NOR circuit N5 or 26 has inputs A2 and C2. The outputs of NOR circuits 24 and 26 supply signals to a NOR circuit N6 designated as 28 via lines 30 and 32, respectively. An output 34 of NOR circuit 28 supplies signals through a gate 36 to a bias amplifier circuit 38 containing in this embodiment three channels operating from a single input through three amplifiers 38R, 38B and 38G to separate outputs. The outputs of bias amplifier circuit 38 are supplied to a cathode ray tube generally designated as 40 through a logic or OR circuit 42. The bias amplifier circuit 38 includes individually variable bias signals from a power supply 44 to the amplifiers 38R, 38B and 38G. Power supply 44 also supplies variable power signals to individual amplifiers 50R, 50B and 50G within a bias amplifier circuit 50 which receives signals from gate 18 and supplies signals to the OR circuit 42 antecedent CRT 40. CRT 40 is one example of a display which may be used in a 3-gun version for supplying as many as eight color hues on the display with the proper biasing and logic circuits.

FIG. 2 is a presentation showing signal levels as either a "zero" signal level or a "one" signal level at each of various points in FIG. 1. Each of columns D, E, F, and G have the same conditions for the colors C1 and C2 but different conditions for the control signals A1 and A2. As will be noted, the A signals are the complements of the corresponding A signals.

In FIG. 3 a display 75 is shown with the letters or information generally designated as 77 depicting the word "Fire" and the words generally designated as 79 depicting the word "Oil."

In FIG. 4 the letter F is broken up into many little bricks or bits of information and the individual bricks or information spaces illustrate the information presented by each of the "ones" supplied by the bias amplifiers 38 and 50 to the CRT 40. As will be noted, the letter F in this particular embodiment is 6 time slots long and 12 lines in height. This, of course, provides good definition and this amount of definition is not always required for a particular presentation.

OPERATION

As previously mentioned, the chart of FIG. 2 represents the voltage amplitudes at various places within the schematic diagram of FIG. 1. The A and C quantities appear at the inputs of the respective NOR circuits while the N quantities appear at the outputs of the respective NOR circuits. Under normal conditions, the A1 and A2 signals will be zero while the A1 and A2 signals will have a one output. As will be realized, a NOR circuit will provide an output only when there is no signal at either one or the other input. Thus, the ones obtained from the A signals prevent any transmission of signal through the particular NOR circuit. With A1 and A2 having zero signal, the color signals being supplied on C1 and C2 are then transmitted through the NOR circuits N3 and N6 and accordingly through the gate circuits 18 and 36 and bias curcuits 38 and 50 to the OR circuit portion 42 of the CRT 40. As will be noted, the C1 and C2 signals are complementary and are utilized to provide color signals to the CRT at complementary times. With only the two signals shown, the outputs from the bias amplifiers may be applied directly to one or the other of the three color guns. However, with more complicated versions wherein it may be desired to provide as an output any one of eight color hues, the signals would be applied to the OR circuit 42 at a level determined by the bias potentiometers 46 and 48. The OR circuit will activate the color guns in accordance with the voltage level supplied thereto to produce a particular color. Further, the OR circuit will be voltage sensitive and select only the highest of a plurality of voltages applied to it in the remote event that more than one level voltage signal is accidentally or intentionally applied thereto.

Thus, it will be realized that the circuitry is slightly more complex than necessary for a two or three color presentation but is based upon circuitry utilized in an eight color presentation wherein the biasing circuits and the OR circuits provide a preferred method of applying signals to the CRT 40.

In the beginning of the description of operation, the normal presentation was mentioned and this is shown in column D of FIG. 2. In this presentation there will be in the first brick or information space a color corresponding to signal C2 while in the second brick a color corresponding to C1. In the third and fourth bricks there will be color corresponding to C2 and in the fifth brick color corresponding to C1.

In column E a signal is applied at A1 which will provide a continuous signal at the output of NOR gate 14 and prevent the presentation of signals at the output of NOR gate 28. Thus, the CRT 40 will receive continuous signals from the bias circuit 50 at the levels set by the biasing amplifiers so that the entire presentation as far as is shown will be of a single color. As will be realized, the two color signals C1 and C2 are still applied to the NOR gates but are merely prevented from being transmitted to the CRT.

In column F the A2 signal is applied. This, of course, provides a continuous signal at the output of N6 and accordingly from the bias circuit 38 to the CRT 40. In this instance, none of the color signals will be transmitted through NOR circuit 14.

It may be determined from FIG. 2, column G that if both signals A1 and A2 are applied, the inverse of the signals will be applied at the outputs of NOR circuits 14 and 28 so that an inverse of colors of the presentation will appear at CRT 40. Thus, four possible presentations are obtainable with the simple two color circuit. One is the normal or preferred mode of presentation of a given color on a given background. The second is a presentation entirely in the color of the normal background. The third is the entire presentation in the normal color of the information. And finally the background and information colors can be reversed.

It may be determined from the previous discussion that the presentation of information as shown in FIG. 3 could have the background 75 in a given color, the word "Fire" in a second color and the word "Oil" in a third color. By merely applying a signal such as A1, assuming that C1 is the background color, the entire presentation would be of the background color and there would be no visible or active information. However, upon the removal of the A1 signal the word "Fire" would appear. Since the word "Oil" is at a different position in the presentation, the A1 signal would have to be applied continuously if it is desired that the word "Oil" should not appear either. However, the A1 signal can be timed to produce selective removal or appearance of a given word.

On the other hand, with a three color presentation and with additional circuitry for FIG. 1, the presentation may be designed such that supplying either one of two inputs would alter the color of one or the other of the words in FIG. 3 so that it would be the same as the background color. In this type of presentation there would be no timing involved since all the words of that given color would be changed to the background color.

While the present disclosure describes a simplified embodiment utilizing two colors, it will be realized by those skilled in the art from the above description of operation that the logic circuitry can be easily modified to provide as many as eight color hues and possibly more color hues upon a display such as a CRT. The logic circuitry may take many forms and for more than two colors will necessarily be somewhat more complex than that shown in FIG. 1.

Claims

1. Apparatus for visually presenting information comprising:

a cathode ray tube having a display surface on which a multicolor display can be generated;

input means for receiving first, second, third, fourth, fifth and sixth binary signals each having first and second states, of which the first and second signals are of opposite binary states, the third and fourth signals are of opposite binary states, the first, second, third and fourth signals are representative of the information to be presented, and of which the fifth and sixth signals are independently representative of the color in which the information is to be presented and the background color;

first, second, third and fourth NOR circuits, each having first and second inputs;

means for connecting said input means to the first and second inputs of said first, second, third and fourth NOR circuits so that the first and fifth signals are supplied to said first NOR circuit, the fourth and sixth signals are supplied to said second NOR circuit, the second and fifth signals are supplied to said third NOR circuit, and the third and sixth signals are supplied to said fourth NOR circuit;

first and second color control means for generating output signals suitable for producing distinct colors on the display surface of said cathode ray tube;

signal combining means for receiving the output signals of said first and second color control means and transmitting only a characteristic one of the output signals to said cathode ray tube;

a fifth NOR circuit having a pair of inputs;

means for connecting the outputs of said first and second NOR circuits to the inputs of said fifth NOR circuit;

a sixth NOR circuit having a pair of inputs;

means for connecting the outputs of the third and fourth NOR circuits to the inputs of said sixth NOR circuit; and

means for controlling said first and second color control means in response to signals produced by said fifth and sixth NOR circuits respectively, whereby said first and second color control means generate characteristic signals only at mutually exclusive times, and whereby the color of the information to be presented and the background color can be transposed, the information can be presented in the background color, or the background can be made the same color as the information by providing first and third binary signals of the same one of the first and second states, by providing the first binary signal of the first state and the third binary signal of the second state, or by providing the first binary signal of the second state and the third binary signal of the first state.