Kodak has Hevised and demonstrated an optical data recording medium using stretched polymeric sheet as a substrate for a coated dye-polymer laser recording. layer. The recording layer is protected by a second stretched, polymeric sheet, parallel to, and 250 pm away. from, the recording sheet- The two sheets are held in tension by an annular metal rim. A plastic centering hub is bonded, to the center of the sheets to allow removal and recentering of the recording medium, (called a sealed disk. assembly - SDA). The SDA is designed to be pulled down over two concentric, annular reference surfaces on the drive platen. The recording sheet stretches to take on the plane defined by the two reference surfaces. Performance data will be presented, on vertical planarity of the recording surfaces, recentering capability, track shape fidelity, and results of temperature and humidity conditioning.