A smart contact lens (400) for detecting a ratiometric change in an incident light (126) intensity is provided, including one or more, preferably concentric, rings (410-1, 410-2, . . . , 410-N) of a liquid crystal display, LCD, type, each ring being operable between a state having a lower attenuation of light and a state having a higher attenuation of light; a circuit (420, 100, 101) for detecting a ratiometric change in an incident light intensity; and a controller (430) configured to operate the one or more rings based on an intensity of an incident light and to, as a response to the circuit (420, 100, 10 101) detecting a ratiometric change in the intensity of the incident light from a higher intensity state to a lower intensity state indicating that at least a beginning of a blinking of an eye of a user has occurred, initiate a re-polarization of the one or more rings. A method of operating the smart contact lens and various uses of the circuit are also provided.