A method and apparatus to automatically control the timing of an image acquisition by an imaging system in developing a correlation model of movement of a target within a patient. The compressor has a piston that moves reciprocally relative to a cylinder to alternately compress air in opposed chambers. and in an inert gas or vacuum atmosphere with an oxygen partial pressure PO2 in a range ofPO2\u2266105\xd7exp {\u22127. All lines in a slice have spans associated with identical sources. In the so-constituted biosensor, a colored component in the inspection target solution can be faded by the bleaching reagent, so that the color in parts other than a reactive area is reduced in consequence, whereby a visual judgment is possible and a more accurate measurement result in which a reading error by a measuring device is extremely suppressed can be obtained. A plurality of optical fibers are inserted through the plurality of openings in the first faceplate and the plurality of openings in the second faceplate.