Abstract: The current invention substantially removes particulate waste materials or debris from the floptical medium after laser etching. A low-temperature gas containing ice crystals is applied at a predetermined angle while the floptical medium is being rotated to improve the cleaning effect. The temperature of the disk is maintained above freezing to maintain the cleaning effect.

Abstract: The current invention provides an apparatus and method of collecting waste materials produced during laser etching of a floptical medium without blocking access to the medium surface. The invention also improves collection efficiency by applying a uniform low-pressure air around the outer edge of the medium. Because the air pressure is applied around the edge, there is no necessity to coordinate a movement or timing of the current invention with respect to the laser etching unit.

Abstract: An apparatus and method for etching a point on the surface of a magnetic medium to reduce the reflectivity of the point and for verifying that proper etching occurred. A light source provides a collimated incident beam of light. The incident beam is focused to a point on the medium and a portion of the beam is reflected. The reflected beam is separated from the incident beam and the intensity of the reflected beam is measured. The measured intensity is compared to a threshold value and verification is indicated if the measured intensity exceeds the threshold value.

Abstract: A beam of light used to etch servo tracks on a magnetic disk is steered with an acousto-optical device to maintain the beam in concentrical patterns while mechanically moving the optics which generate the beam of light continuously radially of the disk.

Abstract: The intensity of a beam of light used to etch concentric servo tracks on a magnetic medium is adjusted with an acousto-optical device to maintain a substantially constant energy density delivered by the beam while the optics which generate the beam move radially of the disk.