OPTICAL COORDINATE INPUT DEVICE

摘要

PURPOSE:To prevent the titled device from detection of light other than that irradiated by a light pen by arranging a filter having a light emitting body absorbing area between a picture display device and an optical waveguide. CONSTITUTION:The filter 6 is arranged between the optical waveguide 6 and the display 2. Light having wavelength less than about 600nm out of that emitted from a picture element 12 on the display 2 is absorbed by the filter 16, a fluorescent substance 14 is not emitted and a photodetecting means 10 decides only the position irradiated by the light pen 4.