Abstract: An audio visual story-telling toy projects pictures on a surface such as a ceiling or a wall while a story recorded on an audio cassette is played. The toy is a small, self-contained unit which includes a tape player and a synchronized picture strip projector. The toy includes an insertable, removable cartridge containing film with picture frames sequenced to correspond to the story on the tape.

Abstract: A video art electronic system for drawing and coloring on a conventional color television video monitor includes a first joystick for drawing and a second joystick for coloring. The operation is in real time and is simple enough for a child to operate.

Abstract: A five stage background filter circuit 10 is disclosed which is capable of responding to background radiation changes at speeds which are from one to two orders of magnitude faster than conventional prior filters. The invention utilizes a cross scan multiplexing technique in combination with filter circuitry depicted in schematic overview in FIG. 1. Circuit 10 includes a differential amplifier 12, a sample and hold device 14, a responsivity corrector 16, a recursive filter 18, and a background subtractor 20. Output signals 11 from a focal plane array of detectors (shown in FIG. 3) are passed through impedance matching input resistors 12a,b to an amplifier. A sample and hold circuit 14a cyclically selects and stores a signal received from first stage 12. The detector outputs are then normalized by responsivity corrector stage 16 which employs a digital-to-analog converter 16a and random access memory 16c.