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Then glue the other prism to the KCP2 centering plate so that it is aligned with the prism already glued. There should be a 1 mm space between the two prisms, and a 1 mm gap between the back face of this second prism and the mount. Note the positioning of the KCP2 piece. This is the final position. Make sure that the mounted prism has some space to move wrt to the edge of the KCP2.
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Make sure the side of the prisms are both aligned to each other and the side of the polaris mount. There should be a 1 mm space between the two prisms, AND a 1 mm gap between the back face of this second prism and the mount. You can use washers as spacers (not shownsee below).
5) Attach one polaris mount to the RM1F cube. Attach this cube with the RS2M spacer to the BA2 baseplate, making sure the cube is orientated such that the corner of the polaris mount is over the center of the BA2. Attach the BA2 to the Optosigma rotation stage, sliding the BA2 so the end of the slots is flush against the screws.
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