Portal de Periódicos da CAPES

<title>High-density optical disk system using a solid immersion lens</title>

1995; SPIE; Volume: 2514; Linguagem: Inglês

10.1117/12.218721

1996-756X

Isao Ichimura, Kiyoshi Osato, Fumisada Maeda, Hideo Owa, Hiroshi Ooki, G. S. Kino,

Semiconductor Lasers and Optical Devices

A solid immersion lens (SIL) attached to a conventional objective could multiply the effective numerical aperture of an optical pick-up by a factor of refractive index n. A truncated hemispherical SIL (n equals 1.5) mounted on a slider, which was designed to follow the movement of the objective, kept good contact between the SIL and a disk substrate with a slight amount of air gap. Our simple configuration enabled the use of this method in an unsealed environment and extended the spatial cut-off frequency by 1.5 times. In addition, the combination with a second-harmonic generation green laser yielded high areal density optical data storage, six times that of current CD systems.