کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5007835 | 1461699 | 2017 | 8 صفحه PDF | دانلود رایگان |
- A novel method of measuring local viscosity of fluid is proposed.
- Two-laser holographic optical tweezers and their applications are presented.
- A new method of measuring weak optical trap stiffness is described.
We report on a two-laser holographic optical tweezers setup and present its two major advantages over single-laser one. First, the trap stiffness of a weak trapping beam can be measured with a considerable accuracy. Second, a novel method of examining local viscosity of fluid is proposed. Both measurements are performed based on forcing the oscillations of a microscopic polystyrene bead placed between two optical traps. The two beams are generated by separate laser sources and therefore their trapping power can vary. Moreover, a stronger trap 'blinks', modulated by an electronic shutter. The blinking frequency can be precisely adjusted to the experimental conditions, which results in high accuracy of the measurements.
Journal: Optics and Lasers in Engineering - Volume 94, July 2017, Pages 82-89