Read-out of a read-only super-resolution optical disc with a Si mask

A novel read-only super-resolution optical disc structure (substrate/mask layer/dielectric layer) is proposed in this paper. By using a Si thin film as the mask layer, the recording pits with a diameter 380nm and a depth 50nm are read out on the dynamic measuring equipment; the laser wavelength α is 632.8nm and the numerical aperture is 0.40. In the course of reproduction, the laser power is 5mW and the rotation velocity of the disc is 4m·s^-1. The optimum thickness of the Si thin film is 18nm and the signal-to-noise ratio is 32dB.