“…However, only two-dimensional (2D) patterns can be obtained. Some optical microscopes with three-dimensional (3D) measurement capability, such as confocal (Masters, 2005), optical coherence tomography (Dubois et al, 2002, 2008), angle deviation (Chiu et al, 2007, 2011), differential interference contrast (Goldberg & Burmeister, 1986; Murphy, 2001), total internal reflection fluorescence (Axelrod, 1989, 2001), scanning near-field (Roy & Knigh, 2010), second-harmonic-generation (Yazdanfar et al, 2004; Yoshiki et al, 2007), etc., are useful for observing images of biological samples. Although most of their resolutions are admissible, the scanning method cannot observe a large area in short time and the algorithms of 3D imaging calculation are typically very complex and computationally intensive.…”