An optical parameter of an eye is detected using an image collection apparatus that collects an image presented by a fundus. An imaging apparatus adjusts an imaging parameter of an optical path between an eye and the image collection apparatus, wherein the image collection apparatus obtains a clearest image that satisfies a defined clarity criterion or condition. An image processing apparatus processes the clearest image to obtain an optical parameter of the eye. The image of the fundus is captured, and an imaging parameter known in the optical path when the clearest image is captured is found, so that a direction currently being watched by the eye and a distance between the eye and a focusing point can be obtained through optical calculation. Consequently, a position of the focusing point of the eye can be determined precisely for a wide range of concurrent applications for eye control interaction.
