A crankshaft or connecting-rod bearing assembly of an internal combustion engine includes a bearing journal configured to function as a bearing inner ring, and a bearing outer ring surrounds the bearing journal. To the cryostats 117 an emergency demagnetizing unit 120 for attenuating magnetic field and a measurement unit 121 for monitoring helium liquid level belong, and signal cables therefor are connected to an inner circuit of the static magnetic field generating magnet 102 via a filter circuit 122. A fast response lens array pair is aligned with a fast response spatial light modulator, and synchronized to provide first and second sets of images with first and second respective directionalities to provide first and second sets of respective optical windows. Each connector column may contain multiple types of connector struts having varying circumferential spans.