Table 1. Examples of objective lenses.

Objective lens	10x air	20x multi	40x oil	63x glycerol	63x oil	100x oil
N.A.	0.4	0.75	1.3-1.4	1.3	1.4	1.4-1.46
W.D. (mm)	2.2-3.1	0.68	0.21-0.24	0.3	0.14-0.19	0.11-0.13
Immersion	-	Water/glycerol/oil	Oil	Glycerol	Oil	Oil
Lateral resolution	2 μm	0.5 μm	0.3 μm	0.25 μm	0.21 μm	0.2 μm
Confocal	+	+	+	+	+	+
Super-resolution	-	-	±	±	+	+
SeeDB2G	±	+	±	+	±	±
SeeDB2S	±	±	+	±	+	+
Suitable sample thickness	< 2 mm	< 1 mm	< 500 μm	< 500 μm	< 300 μm	< 200 μm