FOCUS ERROR COMPENSATION CONTROL SYSTEM FOR COMPENSATING AUTOMATICALLY FOCUS ERROR IN PROCESS FOR CHANGING MAGNIFYING POWER

摘要

PURPOSE: A focus error compensation control system for compensating automatically a focus error in a process for changing magnifying power is provided to shift accurately a magnifying lens to a corresponding magnifying power position by compensating the focus error generated from the process for changing magnifying power after controlling a focus of the magnifying lens. CONSTITUTION: A memory(104) is used for storing a high magnifying power position and a low magnifying power position and storing a focus error compensation algorithm to shift a magnifying lens to a corresponding magnifying power position in a process for changing magnifying power. An input unit(102) receives magnifying power change data and a focus control distance. A control unit(100) receives the magnifying power change data from a user, outputs a focus correction value from the focus error compensation algorithm of the memory, compensates automatically the focus control distance on the basis of the focus correction value, and shift accurately the magnifying lens to the corresponding magnifying power position.