An optical reading subassembly for an automated immunochemistry analyzer, comprising: an optical pipette configured to aspirate a sample from a cuvette as part of a chemistry process on an automated analyzer; a bifurcated fiber optic bundle; an opaque optics box, which mates in a light tight manner with the optical pipette, with a common end and an emission end of the bifurcated optical fiber bundle, with a drain tube, and with a multi-pin electrical power/signal connector; a fluorescence excitation light source; characterized in that the bifurcated fiber optic bundle includes one leg which is connected to the fluorescence excitation light source, and another leg (1214, 1215) which is connected through a series of emission optical filters to a fluorescence detection port of the optics box, and whose common end is connected to the optics box so that it can efficiently illuminate and thereby excite a fluorescent sample in a tip of the optical pipette and simultaneously collect a portion of the emission light from that fluorescent sample; wherein the optical reading subassembly further comprises: a drain port, which allows droplets of fluid from the pipette tip to be removed from the optics box, without introducing stray light into the box; an optical detector with enough dynamic range to measure both fluorescence and luminescence signal from the samples; and a shutter mechanism, which can move the optical detector between a luminescence reading position, a fluorescence reading position, and an optically dark position. an optical pipette configured to aspirate a sample from a cuvette as part of a chemistry process on an automated analyzer; a bifurcated fiber optic bundle; an opaque optics box, which mates in a light tight manner with the optical pipette, with a common end and an emission end of the bifurcated optical fiber bundle, with a drain tube, and with a multi-pin electrical power/signal connector; a fluorescence excitation light source; characterized in that the bifurcated fiber optic bundle includes one leg which is connected to the fluorescence excitation light source, and another leg (1214, 1215) which is connected through a series of emission optical filters to a fluorescence detection port of the optics box, and whose common end is connected to the optics box so that it can efficiently illuminate and thereby excite a fluorescent sample in a tip of the optical pipette and simultaneously collect a portion of the emission light from that fluorescent sample; wherein the optical reading subassembly further comprises: a drain port, which allows droplets of fluid from the pipette tip to be removed from the optics box, without introducing stray light into the box; an optical detector with enough dynamic range to measure both fluorescence and luminescence signal from the samples; and a shutter mechanism, which can move the optical detector between a luminescence reading position, a fluorescence reading position, and an optically dark position. a drain port, which allows droplets of fluid from the pipette tip to be removed from the optics box, without introducing stray light into the box; an optical detector with enough dynamic range to measure both fluorescence and luminescence signal from the samples; and a shutter mechanism, which can move the optical detector between a luminescence reading position, a fluorescence reading position, and an optically dark position.