Multi-element prescription lenses with eye-tracking

A method comprising:

• receiving, from an optical sensor, information about light reflected off an eye of a user, wherein the light is directed to the optical sensor by a doublet lens comprising:
• a proximal lens configured to transmit light toward an eye of a user;
• a distal lens that is configured to, in combination with the proximal lens, correct for at least a portion of a refractive error of the eye of the user;
• and
• a selective transmission interface that:
• couples the proximal lens to the distal lens;
• transmits light within a passband range of wavelengths that comprise at least a portion of a visible spectrum of light;
• and
• is at least partially non-transmissive outside the passband range;
• detecting, based on the information about the light reflected off the eye of the user, a gaze of the user;
• and
• in response to detecting the gaze of the user, changing a state of an optical system worn by the user, wherein the optical system comprises the optical sensor and the doublet lens, wherein the selective transmission interface is configured to reflect at least a portion of an infrared spectrum of light such that infrared light reflected from the eye of the user is diverted toward the sensor.