An imaging system, comprising: a laser light source; a differential splitting window to split the light emitted from the light source into a plurality of parallel beams; a sample container (330, 392)) comprising first, second and third layers (334, 336, 338) disposed on a substrate in touching relation, the layers (334, 336, 338) comprising first reflective surface at the first layer of the sample container, a second reflective surface between the first and second layers a third reflective surface between the second and third layers, and a fourth reflective surface between the third layer and the substrate; an objective lens positioned to focus light from the light source onto at least one of the second and third reflective surfaces (S2, S3) and to receive light reflected from the sample container; an image sensor comprising a plurality of pixel locations positioned to receive light reflected from the sample container; a first blocking structure positioned to block a reflection from the first surface from reaching the image sensor; and a second blocking structure positioned to block a reflection from the fourth surface from reaching the image sensor, the second blocking structure comprising a frame defining an aperture; first and second elongate structural members each comprising first and second ends, wherein the first and second elongate structural members are connected at their first ends to the frame at opposite sides of the aperture, wherein the first and second elongate structural members extend from the frame parallel to and in the same direction as one another, and an optically opaque blocking member positioned to extend between the respective second ends of the first and second elongate structural members, the optically opaque blocking member having triangular cross-section and a blocking face, wherein the second ends of the first and the second elongate structural members are tapered such that the edges at the second ends are angled, and wherein the blocking face is angled relative to a plane of the frame allowing for the blocking face to be placed adjacent to and at substantially the same angle as an adjacent beam splitter. a laser light source; a differential splitting window to split the light emitted from the light source into a plurality of parallel beams; a sample container (330, 392)) comprising first, second and third layers (334, 336, 338) disposed on a substrate in touching relation, the layers (334, 336, 338) comprising first reflective surface at the first layer of the sample container, a second reflective surface between the first and second layers a third reflective surface between the second and third layers, and a fourth reflective surface between the third layer and the substrate; an objective lens positioned to focus light from the light source onto at least one of the second and third reflective surfaces (S2, S3) and to receive light reflected from the sample container; an image sensor comprising a plurality of pixel locations positioned to receive light reflected from the sample container; a first blocking structure positioned to block a reflection from the first surface from reaching the image sensor; and a second blocking structure positioned to block a reflection from the fourth surface from reaching the image sensor, the second blocking structure comprising a frame defining an aperture; first and second elongate structural members each comprising first and second ends, wherein the first and second elongate structural members are connected at their first ends to the frame at opposite sides of the aperture, wherein the first and second elongate structural members extend from the frame parallel to and in the same direction as one another, and an optically opaque blocking member positioned to extend between the respective second ends of the first and second elongate structural members, the optically opaque blocking member having triangular cross-section and a blocking face, wherein the second ends of the first and the second elongate structural members are tapered such that the edges at the second ends are angled, and wherein the blocking face is angled relative to a plane of the frame allowing for the blocking face to be placed adjacent to and at substantially the same angle as an adjacent beam splitter.