Abstract: An eraser for an electronic blackboard. System whose erasing area is variable according to the size and accuracy of the figure to be erased. The eraser includes a main unit carrying a small area erasing unit, and a large area erasing unit which is detachably engaged to the main unit. Detectors installed in the main unit detect when the eraser is touched on the surface of the board, and/or that the large area erasing unit is being used, and send an appropriate signal to the system controller.When the system controller receive the signal, it blanks the memories corresponding to the area covered by the erasing units and erases the corresponding area of figures displayed on the display unit.

Abstract: An apparatus for storing unused felt pens for use in an electronic input board system includes a plurality of pen loaders. In systems in which multiple color information is written on the electronic board, colored felt pens are provided and one of these color felt pens is replaceably mounted in a pen holder. In order to prevent drying out of ink, the unused felt pens are sealed with a cap which is positioned within each pen loader. When a felt pen is loaded into the pen holder to write a letter or a graphic pattern of a selected color, a switch detects which felt pen has been selected for loading in the pen holder, and the system identifies the color of the pen. The apparatus maintains the points of unused felt pens airtightly sealed within the cap to protect them against drying out of ink, while allowing a single-handed operation for loading/unloading a felt pen into/from the pen holder without staining the operator's fingers, clothes, etc. with ink.