Figure 12.

Snapshots showing the stable trapping of yeast cells at an optical power of ≈15 mW, @980 nm by micro-lenses (A) 3A and (B) 2B, fabricated using photopolymerization laser power values of 10 $\mathsf{\mu }$W and 20 $\mathsf{\mu }$W, respectively. (A-I,II) After the laser is turned on and the micro-lens displaced to the right, the yeast cell moved towards the right ($+x$ direction) due to optical trapping. (A-III,IV) Then, the yeast cell is displaced towards the $-y$; (A-IV,V) $+y$ and (A-VI,VIII) $-x$ directions, by performing a similar assay. (B, I-VIII) Snapshots showing yeast cell displacements towards the $+x$, $-x$, $-y$ and $+y$ directions, due to trapping forces exerted by the lens 2B, respectively.