Progressive differential push-pull method for dual-layer blu-ray disc recording. - Hironori Nakahara; Kenya Nakai; Toshiya Matozaki; Nobuo Takeshita (IEEE Trans. Consumer Electron., 2010)

Fast adjustment method of spherical aberration and focus offset by elliptic equation. - Y. Kanatake; Toshiya Matozaki; Nobuo Takeshita (ICCE, 2013)