METHOD AND APPARATUS FOR DETECTING THE MINIMUM GLIDE HEIGHT OF A FLYING HEAD AND FOR FOCUSING A LENS CARRIED ON A FLYING HEAD

摘要

A flying head comprises a lens which is movably affixed to the body having an air bearing surface. The flying head system may also comprise a focus sensor and focus controller. A method of focusing a laser beam is also claimed. Another aspect of the application is a flying head comprising a contact sensor having an electrical connection that carries a signal indicative of contact between the flying head and the recording medium. According to another aspect of the application a flying head comprises a lens affixed to a body, and an electric heater mounted to the body, which changes the focus of the lens when a current flows in the electric heater.