Structural Analysis of Optics
Typical structural designs in most industries are governed by failure due to stress—either yield, ultimate, or fatigue. An optical structure’s performance is usually determined by distortions or displacements rather than stress—leading to stiffness-limited design. Most mirrors or lenses have distortion requirements measured in fractions of wavelengths of light. At this level of distortion, the stresses are usually quite small. Similarly, optical systems typically have tight optical beam-pointing requirements, or tight image motion requirements, which keep stresses in metering structures low. To predict the behavior of optical structures to the level of their performance specifications, analyses must have a high degree of accuracy. Thus, analysis techniques or assumptions commonly used in other industries may not be appropriate for optics.