Canon has filed a patent for an eye-controlled focus system that can ascertain the position of your eye’s gaze to determine where to place your AF point.
The technology is actually fairly similar to a feature used in Canon’s old film cameras, as Canon News points out.
According to the patent it uses light sources to illuminate the sight of your pupil, while a half mirror enables the image sensor to monitor your eye’s position.
The patent text explains:
In addition, a display element 10 composed of a liquid crystal or the like for displaying a captured image, a display element driving circuit 11 for driving the display element 10, and an eyepiece 12 for observing a subject image displayed on the display element 10 are provided. Has been placed. Reference numerals 13a to 13b denote light sources for illuminating the photographer’s eyeball 14 for detecting the direction of the line of sight from the relationship between the elephant and the pupil reflected by the cornea reflection of the light source conventionally used in a single-lens reflex camera or the like. The infrared light emitting diode is disposed around the eyepiece 12. The illuminated eyeball image and the image by corneal reflection of the light sources 13a to 13b are transmitted through the eyepiece lens 12, reflected by the light splitter 15, and the eyeball lens in which the photoelectric element array of the CCD ridge is arranged two-dimensionally by the light receiving lens 16. An image is formed on the image sensor 17. The light receiving lens 16 positions the pupil of the photographer’s eyeball 14 and the image sensor 17 for the eyeball in a conjugate imaging relationship. The line-of-sight direction is detected by a predetermined algorithm, which will be described later, from the positional relationship between the eyeball imaged on the eyeball image sensor 17 and the corneal reflection of the light sources 13a to 13b.