Optical Tweezers

Optical Tweezers

Resources

• [1] Directions on how to use a QPD in an optical tweezer setup.
• [2] Here are some slide prepping instructions from Berkeley.

Our own setup

• Here's how we did our Slide Set-Up.

Using NI Vision Assistant

• [3] Image Acquisition/Saving Images
• [4] How to track the microspheres in NI Vision Assistant using pattern matching.

Our calculations using Brownian Motion

• 2.56 micrometer spheres
  • 4.6 mW Beam [5]

Calculating Trap Forces Using Stokes' Drag Force

• Beam Power (mW)	Escape Velocity (microns/second)	Trap Force (pN)
  5.5	20.57	0.88
  8.5	33.49	1.44
  11.7	40.00	1.72
  15.3	62.60	2.69
  19.0	84.71	3.64
  23.0	110.77	4.76

• File:Http://i105.photobucket.com/albums/m234/Brian Perrett/TrapForceMeasurementGraph1 zps502a6eea.png