Spectacle lens having continuously variable controlled density and fast response time

摘要: A spectacle lens comprises a liquid crystal layer and electrode assembly sandwiched between pair of identically curved glass plates layers polarization material on the outer surfaces plates. The optical density is controlled by applying across electrodes variable duty cycle voltage pulses having magnitude greater than threshold frequency at least as great critical flicker fusion eye. in response to ambient light intensity measured photocell. In order reduce time increase operating lifetime layer, tir-level (+V, 0, -V) rather bilevel 0) may be applied electrodes.