1. A hand pattern switching apparatus which operates an object equipment based on the result of the image taken by an image pickup means for taking an image of movement of a hand, comprising: means for saving the image taken in a state where a hand does not exist in an image pickup area of the image pickup means, as an initial image data; differentiation means for obtaining a difference image data between an original image data, which is the image taken in a state where a hand exists in the image pickup area of the image pickup means, and the initial image data, to determine a part of the difference image data corresponding to a place close to a hand; luminance detection means for obtaining an average luminance of the original image data corresponding to the part of the difference image data in a place close to the hand obtained by the differentiation means; and processing means for performing binary processing of the original image data by a threshold value based on the average luminance obtained by the luminance detection means.