Table 1.

Specifications of two OCT systems.

OCT system	Cutting (slice) direction	Area	Resolution	Observation
Proto 3(DT)	Vertical	Horizontal: 14 × 14 mm Vertical: 2.3 mm	Horizontal: 20 μm Vertical: 9 μm	Attachment between human cardiac cell sheets (Figure 2)
IVS-2000		Horizontal: 6.5 × 6.5 mm Vertical: 3.9 mm	Horizontal: 8.7 μm Vertical: 8.7 μm	Beatings of human cardiac cell sheets (Figures 3–5 and Supplementary Movies 2–4)