A paper tray assembly for providing imaging media to an imaging apparatus, includes a base cassette and an insert cassette. The catheter accommodates, in addition to the customary instruments necessary to carry out its task, three ultrasound receivers that are mounted at a distance from one another on the tip of the catheter and are capable of detecting the arrival of scan signals of the ultrasound transducer. Each imaging system has separate pre-scan and post-scan optical assemblies. The outer frame is adapted to be installed in one of the wall and the cabinet and is rotatably attached to the inner frame whereby the inner frame may be pivoted such that the television is rotatable at least 180 degrees. In addition, an ink cartridge includes a space for receiving an ink and at least one air vent in which the air-permeable filter is provided.