An optical assembly incorporating a wedge-shaped optically transparent prism, a 45 degree right isosceles triangular prism which has two thin film coated surfaces, a rhomboidal prism attached to the triangular prism, a second, smaller 45 degree right isosceles triangular prism attached to one end face of the rhomboidal prism and two planoconvex lenses attached to the combination of the rhomboidal and second triangular prisms is mounted within a housing. All of the optical components are cemented to the adjacent component utilizing a transparent optical cement to form an integral unit. Data and servo detector assemblies and a diode laser light source are mounted on the external surfaces of the housing to form a stationary optical assembly which provides the following functions: generates a collimated beam of light whose power output may be modulated electronically to perform read, write and erase functions; generates an electrical data signal derived from a portion of a returning light beam; and generates suitable electrical error signals for servomechanical control of radial and axial motion of a focused light spot on information storage media.