Abstract We report the construction of an optical tweezers system and the results of the trapping and the moving of living algal cells. Experimental study on trapping polystyrene spheres demonstrates the effects of the system parameters on the trap. The trapping forces on dielectric spheres are calculated using Ashkin's ray-optics model. The result shows that an objective with higher numerical aperture can build a more stable trap along axial direction than an objective with lower numerical aperture, though their transverse trapping forces are on the same order.
Received: 03 April 2000
Revised: 07 June 2000
Accepted manuscript online:
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.