Disclosed is a wearable optical devices for a human subject, comprising: a transparent lens; a wearable frame configured to maintain the lens in front of an eye of a human subject; a transparent pixelated active optical element where the pixels of the active optical element have an optical property with a changeable value; an eye tracker; and a controller configured to set a value for an optical property of the pixels of the active optical element so as to create an image mask through which at least some of the light reaching the feye passes through, thereby modifying the image formed on the retina of the first eye.