Abstract: A device that uses a laser beam to access data stored on an optical disk is disclosed. The laser beam is confined in a thin film optical waveguide having electrodes mounted onto the surface of the waveguide. The electrodes are arranged to form a coarse adjustment section, which adjusts the beam's direction to coincide with the data track of the optical disk to be accesses, and an electro-optic focus, which focuses the beam onto the surface of the optical disk. The electrodes are selectivity supplied with voltages from a control circuit. When the electrodes are energized, the index of refraction of the waveguide is altered, causing the beam direction and focus to be adjusted so as to coincide with and become focused onto the data track. After reflection off the data track, the beam impinges upon an array of photodetectors. The photodetectors provide a feedback signal to the control circuit which is used to continually adjust the beam direction and focus as the optical disk is read.

Abstract: A device that uses a laser beam to access data stored on an optical disk is disclosed. The laser beam is confined in a thin film optical waveguide having electrodes mounted onto the surface of the waveguide. The electrodes are arranged to form a coarse adjustment section, which adjusts the beam's direction to coincide with the data track of the optical disk to be accessed, and an electro-optic focus, which focuses the beam onto the surface of the optical disk. The electrodes are selectively supplied with voltages from a control circuit. When the electrodes are energized, the index of refraction of the waveguide is altered, causing the beam direction and focus to be adjusted so as to coincide with and become focused onto the data track. After reflection off the data track, the beam impinges upon an array of photodetectors. The photodetectors provide a feedback signal to the control circuit which is used to continually adjust the beam direction and focus as the optical disk is read.