The wearable heartbeat measuring device is accomplished by wearing a wrist-watch-like heart monitor device on the wrist. In one example, a method is provided for executing a re-imaging process for replacing an original image on an active system of a remote computer system with a new image. The prediction signal generation method controller also determines a motion vector and a reference picture for each respective target block by performing motion prediction. The output of the light modulator is a line image which may be scanned to form a two-dimensional image. The operation of an approach driving portion is controlled on the basis of the calculated approach driving conditions.