| 摘要 |
PURPOSE:To increase the effective area of material for optical recording medium of ROM type, DRAW type and E-DRAW type and to realize higher recording density, higher contrast and less error by forming the recording layer of step-like profiles. CONSTITUTION:A transparent substrate 1 comprising org. polymer material or glass is molded in a step-like shape by injection molding, etc. The angle 2 of the step is preferably 60 - 120 deg. which gives the effective area 2 - 1.15 time as large as the one without steps. The pitch 3 of the step and the width 4 of recording tracks are determined according to the optics of light source which generates a beam spot, and preferably >=1mum. Optical recording material 5 is then deposited thereon. Informations are recorded in bits 6 by optical, thermal or thermomagnetic method and reproduced with light perpendicular to the objective recording area. Therefore, reflected light from other steps do not influence on recording/reproducing, so that errors are largely reduced as well as no guideline is needed for tracking. |
