subject: Digital Led Writing Board [print this page] Conventionally, these types of LED writing board have included boards, as illustrated in laid-open Japanese Patent Application KOKAI No. 7-90214, in which letters, characters and pictures are written on the LED writing board using a LED writing tool. When all the information produced by the LED writing tool is to be erased, the surface of the LED writing board is wiped with a wiping tool soaked with a cleaning liquid such as water, taking advantage of a chemical reaction for erasing the letters, etc.
A digital computer LED writing board of the present invention is mainly based on the piezo-electric characteristics of a soft film piezo-electric material such as Polyvinyliden Fluoride (PVDF) with a thickness approximately 30 um (even thinner than that of a common paper). A uniquely designed LED writing board of high resolution constructed of such material together with necessary detection circuits connected to a computer forms a device suitable for LED writing or drawing the characters or graphs with a common LED writing instrument (pencil, ball pen) and storing them into a memory or displaying them on a screen, or printing out in their original patterns without any change.
Based on the above discussion on the digital computer LED writing board of the present invention, the fine electrode lines by groups of high, low soft piezoelectric film are disposed perpendicularly to each other to combine insulation film, resilient pad and protective film in performing the scanning and detection by groups within scanning, detection circuits to form a computer LED writing board of high resolution, in which a common LED writing instrument can be used to write or draw directly, while the character tracig and groups signal can be read in their original form and to achieve a goal of having all written or drawn stored in a memory, or displayed on a screen, or printed out accurately with their fidelity. The present invention of computer LED writing board has a complete new and inventive design with highly practical value.
In this connection, the digital computer LED writing board of this invention is essentially a LED writing faceplate of high resolution constructed with a soft film piezoelectric material. It is suitable for LED writing or drawing conveniently with a common LED writing instrument with the character tracing and/or graphic forms thus produced input in a high fidelity to a computer memory for storage or for a display on the screen, or for printing out, so as to achieve a goal of having a handLED writing or graphic form reproduced completely in its original form.
