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: a means for saving the image taken in the state that a hand does not exist in the image pickup area of the image pickup means, as an initial image data; a differentiation means for obtaining a difference image data between an original image data that is the image taken in the state that a hand exists in the image pickup area of the image pickup means, and the initial image data; a luminance detection means for obtaining an average luminance in a place close to a hand based on the image data of a place close to a hand obtained by the differentiation means; and a processing means for performing binary processing of the original image data by a threshold value based on the average luminance calculated by the luminance detection means.