Optical Tweezers

Optical tweezing and trapping

A highly focused laser beam creates a force attracting particles to the centre of the beam. This electric field gradient, typically in the order of piconewtons, can be used to trap and manipulate microscopic particles and is particularly useful for biological single cell manipulation. The single cell can be held in the beam waist, the point which forms the centre of the beam for further analysis such as IR or Raman spectroscopy. By trapping a number of particles in different laser beams inter molecular forces can be investigated.

The laser used for optical tweezing and trapping can be a range of different wavelengths, but it is common to use the Infrared region when working with biological samples to reduce absorption of light energy that can cause cell heating. The laser should however have a good beam quality with an M2 close to unity and a high pointing stability to maintain the position of the focus and beam waist. 

Many of Laser Quantum’s lasers are suited to optical tweezing and trapping as they all have M2 close to unity, with a high degree of pointing stability. Additionally single mode fibre coupling is available on all the lasers to enable easy integration and positioning of the beam output.

  • opus - High powered 532 and 1064nm (10W)
  • ventus – Compact design with good beam quality. Available in both 532nm and 1064nm options
  • finesse - Very high power, especially when more than one beam is needed to create multiple traps

Available Products