Lens induced by stress in optical windows for high-pressure cells

Calculations are described of the elastic stress, strain, and surface displacement for a high-pressure optical window consisting of a transparent cylinder which is supported on a flat seat with an axial hole (Poulter window). Under pressure the window is compressed, and its outside surface bulges through the hole in the support. The net optical effect is to create a weak positive lens and to increase the axial optical thickness of the window.