The prime purpose of the optical component-to-mount interface is to hold the component (here a prism or small mirror) with minimal self-weight distortion in its proper position and orientation within the optical instrument. This implies the application of mechanical constraints, i.e., external forces that limit component motions in the normal gravity environment, when the temperature changes, or when external mechanical disturbances occur. How these constraints should be applied is the first topic considered in this chapter. The advantages of semi-kinematic mounting techniques are explained. We then explore how the applied forces may cause stresses and birefringence to develop within the component. The generalizations on mounting stresses given here are the subjects of more detailed, quantitative discussions in Chapters 5 and 8. The chapter closes with brief considerations of cost and manufacturability of the components and their mounts.
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