A respirator 15 has a harness 10 that allows the respirator body 20 to be conveniently disposed beneath a wearer’s chin when not in use. The liquid crystal display device includes a first substrate and a second substrate opposed to the first substrate by way of liquid crystals, and a sealing material formed outside the display area where a plurality of pixels are formed. The method also includes examining the preceding and succeeding fields for motion at a locus of a current pixel to be interpolated. A control unit judges on the basis of the operation rate of the processor collected by the monitoring unit and the control information stored in the control information memory unit whether it is necessary to modify the performance or not and controls to modify the performance of the processor on the basis of the judged result.