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First of all,
I gonna use a <30mW Laser, to not burn your eyes use Laser-safety-goggles and become sure no one get harmed by your actions. While working on the tweezer it's safer not to wear an metallic or reflective stuff and use anodized tools.
A few more details on this development, I have built up that construction in recent weeks at the University of Tübingen for the beginner training in physics. This structure will cost quite a lot of money but who can afford it will surely have a lot of fun with it.
In this structure, polystyrene beads are used as colloids. Since the diameter is much larger than the wavelength of the laser I will add only the geometric explanation of optical tweezers.
The distances between the individual optical elements are only of secondary importance. But I will explain every part of what is important in the beam path as the laser beam and look lost.
I know this instruction is not very good but with your help and some time it will be helpfull.
I gonna use a <30mW Laser, to not burn your eyes use Laser-safety-goggles and become sure no one get harmed by your actions. While working on the tweezer it's safer not to wear an metallic or reflective stuff and use anodized tools.
A few more details on this development, I have built up that construction in recent weeks at the University of Tübingen for the beginner training in physics. This structure will cost quite a lot of money but who can afford it will surely have a lot of fun with it.
In this structure, polystyrene beads are used as colloids. Since the diameter is much larger than the wavelength of the laser I will add only the geometric explanation of optical tweezers.
The distances between the individual optical elements are only of secondary importance. But I will explain every part of what is important in the beam path as the laser beam and look lost.
I know this instruction is not very good but with your help and some time it will be helpfull.
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Signing UpStep 1The Theory of Everything...
... not really everything, but everything about our experiment. So first of all, we need an understanding of light, in our case, we do not need a wave properties thus extends the idea of photons and the geometric optics from perfect.
Suppose the photons are moving along the steel. The residence is located Probability for a photon in the center and the highest falls in the form of a binomial distribution, more or less. So we have many photons in the center and outward circular symmetrical less.
Now, a photon hits our test particles and is broken in our particles. If a particle is deflected wid which has a momentum change zurfolge, this momentum change causes a force on the refracting medium.
In the center are the photon balance (around it) and it has no force on the particle in the x or y direction, but strength in the beam direction will be repealed by the glass.
Now, if a particle is not exactly in the center then creates a force imbalance. Where more photons are incident (as a center detail) results in a greater momentum change and thus tension toward the center than on the side with lower photon intensity (number). The particle is thus pulled into the center.
As these forces are very small, only a few pico-Newton, we have no relation to everyday. But in a force-free system such as ours, these forces are superior, therefore the particle can be captured with the laser and move.
Suppose the photons are moving along the steel. The residence is located Probability for a photon in the center and the highest falls in the form of a binomial distribution, more or less. So we have many photons in the center and outward circular symmetrical less.
Now, a photon hits our test particles and is broken in our particles. If a particle is deflected wid which has a momentum change zurfolge, this momentum change causes a force on the refracting medium.
In the center are the photon balance (around it) and it has no force on the particle in the x or y direction, but strength in the beam direction will be repealed by the glass.
Now, if a particle is not exactly in the center then creates a force imbalance. Where more photons are incident (as a center detail) results in a greater momentum change and thus tension toward the center than on the side with lower photon intensity (number). The particle is thus pulled into the center.
As these forces are very small, only a few pico-Newton, we have no relation to everyday. But in a force-free system such as ours, these forces are superior, therefore the particle can be captured with the laser and move.
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Cool setup and looks like something out of the TV show, big bang theory..... but have no clue what your goal is.....
In our case d>\lamda we just need a transperent particel.
In your introduction, it would be very useful to provide some of the theory and purpose behind optical tweezers. Explain a bit about why they are used, how they work (in particular the focusing waist), and how to control them. Then start with Step 1 on the materials and assembly instructions.
In your final step, it would be really great if you able to connect a small video camera to your microscope, and upload a few pictures showing your tweezers in action.
The two drawings you've included are annotated in German. Because they are images, rather than text, users cannot easily run them through online translators. Could you provide in the text a translation to English of the terms involved, or a more detailed explanation of the drawings, for the many readers who are not already familar with the science?
A small note about terminology. In American English, the term "breadboard" refers to an electronic protoyping unit, with many holes spaced at 0.1-inch (2.54 mm) intervals and electrically connected. I believe that you are refering to an optical bench or optical table for this project.