Patent No. 4616261 Method and apparatus for generating subliminal visual messages

 Patent No. 4616261  Method and apparatus for generating subliminal visual messages (Crawford, et al., Oct 7, 1986)

ASSIGNEE: Stimutech, Inc., Ann Arbor, MI

Abstract

A system for generating a subliminal message during the display of a normal television program on a television receiver utilizes a personal computer to generate an RF carrier modulated with video signals encoding the subliminal message. The computer runs under the control of an application program which stores the subliminal message and also controls the computer to cause it to generate timing signals that are provided to a single pole double-throw switch. The source of the normal television program and the video output of the computer are connected to the two switch inputs and the switch output is connected to the television receiver antenna system. The timing signals cause the switch to normally display the conventional television program and to periodically switch to the computer output to generate the subliminal message. The video output of the computer includes horizontal and vertical synchronizing signals which are of substantially the same frequency as the synchronizing signals incorporated within the normal program source but of an arbitrary phase.

Notes:

FIELD OF THE INVENTION

This invention relates to a method and apparatus for causing the generation of a subliminal message superimposed on a supraliminal program being displayed on a television receiver.

BACKGROUND OF THE INVENTION

A substantial body of scientific evidence exists to support the proposition that a human subject may be influenced by visual messages generated at intensity and duration levels sufficiently low that they are not consciously perceived by the subject. U.S. Pat. Nos. 3,060,795 and 3,278,676 disclose a variety of systems adapted to display a supraliminally perceptible visual image having a subliminally perceptible message superimposed thereon. These patents disclose motion picture and television systems for displaying conventional programs along with secondary visual signals that have such low levels of intensity and/or duration that they are not consciously perceptible by a human observer but are capable of impressing themselves upon the subconscious mind of the observer to influence behavior.

The systems disclosed in these patents as well as the subsequent subliminal visual message system disclosed in U.S. Pat. No. 4,006,291 all involve arrangements wherein both the source of the supraliminal program signal and subliminal message signal are under control of the system's operator. In the motion picture version disclosed in U.S. Pat. No. 3,060,795, a pair of separate motion picture projectors employ mechanism connecting them so that they operate in synchronism to generate the supraliminal program signal and the superimposed subliminal mesasge. In the television versions disclosed in the above-noted patents, pairs of television cameras are used to generate the two signals and their outputs are synchronized to provide a combined signal suitable for use directly by a television receiver or for radio transmission to remote receivers.

The highly specialized apparatus required for these prior art systems has severely limited their application. If a subliminal mesasge system could be formed with readily available equipment, such as a home television receiver, which could use conventionally broadcast programs as the supraliminal program source, it would have great utility for impressing the observer with subliminal message that might educate the observer or direct him or her toward desirable action.

SUMMARY OF THE INVENTION

The present invention is accordingly directed toward a method and apparatus for superimposing subliminally perceptible messages on a conventional television receiver which is displaying normal program sources derived from broadcast or cable TV, a video record or the like. The system is intended to be attached to an entertainment television receiver without the necessity of any mechanical or electrical modification of the television set. It utilizes as its primary components apparatus often available in the home for other purposes.

Broadly, the present invention provides means for generating a video signal encoded with a subliminal message and horizontal and vertical synchronizing signals which are of substantially the same frequency as those forming part of the supraliminal signal source connected to the receiver but have an artibrary phase with respect to the supraliminal synchronizing signal. The present invention further contemplates a single pole double-throw RF switching device having inputs from the supraliminal program source and the subliminal message source and having an output to the television receiver. The switch is controlled so that it normally is connected to the supraliminal program source causing the receiver to display that program under control of the horizontal and vertical synchronizing signals forming part of the program composite signal. At regular intervals the switch is controlled to disconnect the program source from the television receiver and supply the subliminal signal with its independent synchronizing signals. The subliminal signal may be applied to the receiver for as little as 500 microseconds, but, in the preferred embodiment, it is generated for the time required to display one full raster field on the television screen, normally about 1/60th of a second. During this time, the synchronization generators of the television receiver are under the control of the synchronizing signals forming part of the subliminal program source and will switch the phase of the generated raster scan to match these new synchronizing signals. The subliminal message will, therefore, be generated on the TV screen during one raster scan or field.

In order to assure synchronization of the vertical and horizontal synch signals as well as synchronization of color signals, AFG and AGC, display of the subliminal message is delayed from one to 24 picture fields following switching off from the supraliminal program source. During this delay, a completely black or blue field is displayed so that the synchronization is not perceived by the viewer. The delay is not visually objectionable and does not negatively affect the device as a subliminal generator.

In the preferred embodiment of the present invention a subliminal video signal is generated by a general purpose computer, preferably of the "home" or "personal" type, running an application program which causes repeated generation of the subliminal video message, once for each raster field, at the video output of the computer. The application program also causes the generation of two-level switching signals for the antenna switch and also synchronizes display of the subliminal program material with vertical retrace signals so that the program material or "message" is displayed at a predetermined position in each picture field. In one embodiment of the invention, which will subsequently be disclosed in detail, the application program for the computer takes the form of a module, including a read-only memory (ROM), adapted to be connected to the computer. The module may also contain a bistable switching device (flip-flop) for generating the timing signals. Alternatively, the application program may make use of a flip-flop and an output port available on the computer to generate the timing signals. The application program stored in the ROM causes the computer to generate logic level signals which are applied to the flip-flop and cause it to provide a higher power output switching signal. This switching signal is coupled to the RF switch, along with the subliminal RF signal, and controls its operation.

In an alternative embodiment of the invention, the subliminal message is not encoded in the application program but the application program allows the computer operator to input to the computer the particular subliminal message that is to be displayed.