A hybrid imaging apparatus comprising • a magnetic resonance imaging, MRI arrangement having an RF resonator structure and a gradient coil system with a longitudinal axis (z), • an emission tomography, ET arrangement having a detector device comprising a photosensor and a circuit board arrangement with at least one readout circuit board on which an ET electronics is arranged, • an internal shielding device (7, 7a, 7b, 7c) for mutually shielding the ET electronics of the ET arrangement and the RF resonator structure of the MRI arrangement, wherein the photosensor is arranged, in relation to the longitudinal axis, radially inside the circuit board arrangement and radially outside the RF resonator structure, wherein vias (12a, 12b, 12c) are provided in the shielding device (7, 7a, 7b, 7c), wherein • the internal shielding device is integrated in the photosensor and the photosensor is provided with vias through the internal shielding device that is integrated in the photosensor, or • the internal shielding device is integrated, in relation to the longitudinal axis (z), radially outside the photosensor in at least one sensor circuit board of the circuit board arrangement and the at least one sensor circuit board is provided with the vias for signal and supply lines, or • the internal shielding device is integrated, in relation to the longitudinal axis (z), radially outside the photosensor in readout circuit boards of the circuit board arrangement, wherein electrically conducting circuit board layers of the readout circuit boards form the inner shielding device or are part of the inner shielding device and the vias are provided in sensor circuit boards and the readout circuit boards, and characterized in that an RF filter is integrated in the inner shielding device (7, 7a, 7b, 7c) or the circuit board arrangement. • a magnetic resonance imaging, MRI arrangement having an RF resonator structure and a gradient coil system with a longitudinal axis (z), • an emission tomography, ET arrangement having a detector device comprising a photosensor and a circuit board arrangement with at least one readout circuit board on which an ET electronics is arranged, • an internal shielding device (7, 7a, 7b, 7c) for mutually shielding the ET electronics of the ET arrangement and the RF resonator structure of the MRI arrangement, wherein the photosensor is arranged, in relation to the longitudinal axis, radially inside the circuit board arrangement and radially outside the RF resonator structure, wherein vias (12a, 12b, 12c) are provided in the shielding device (7, 7a, 7b, 7c), wherein wherein the photosensor is arranged, in relation to the longitudinal axis, radially inside the circuit board arrangement and radially outside the RF resonator structure, wherein vias (12a, 12b, 12c) are provided in the shielding device (7, 7a, 7b, 7c), wherein • the internal shielding device is integrated in the photosensor and the photosensor is provided with vias through the internal shielding device that is integrated in the photosensor, or • the internal shielding device is integrated, in relation to the longitudinal axis (z), radially outside the photosensor in at least one sensor circuit board of the circuit board arrangement and the at least one sensor circuit board is provided with the vias for signal and supply lines, or • the internal shielding device is integrated, in relation to the longitudinal axis (z), radially outside the photosensor in readout circuit boards of the circuit board arrangement, wherein electrically conducting circuit board layers of the readout circuit boards form the inner shielding device or are part of the inner shielding device and the vias are provided in sensor circuit boards and the readout circuit boards, and