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ArcticMyst Security by Avery

Laser "microscope"

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So i was playing with my laser, and went to view the dot about 100' away. A shadow of a mosquito could be seen in it, magnified many times. Due to the intense brightness of the light, some light went through the mosquito and it was slightly transparent.
 





Moptsp

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So the laser was right in front of the mosquito and you walked down to where the beam hit, and the enlarged image was the shadow? I imagine that could work well with laser light. Because of the more organized array of waves compared to a regular light source at which would make it quite blurry.

Cool. :)
 
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Amazed that you got a mosquito to sit still for you. You must have made buddies with him or bought him a :beer:.
They have always been mean to me. :(

As they say 'pics or it didn't happen'. I don't doubt, just want pics.
 

aXit

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If you suspend a drop of pond water (like hanging from an eyedropper) and direct a beam of light through the spherical section so it's enlarged and projected onto a screen, you can see bacteria moving around inside the drop.

Fun experiment.
 

Things

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Lasers work as microscopes because the light is coherent. With normal light, it'd hit the object and just merge back into a dot at the other end. With a laser, the light hits the object, but keeps going in a straight line. Try it with a piece of hair as well.
 
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Are you sure its not some kind of diffraction effect?

Shine a laser through a tiny hole, and you should get a ring on the other side, not just a dot.

Shine a laser beam over a tiny dot, you get a black ring with diffracted light in the center, not a complete shadow of the object.
 
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If you suspend a drop of pond water (like hanging from an eyedropper) and direct a beam of light through the spherical section so it's enlarged and projected onto a screen, you can see bacteria moving around inside the drop.

Fun experiment.

How do you know what you're seeing is bacteria?
 
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This was how sun spots were viewed before the advent of a sun lens. Think: pin hole camera, for an eclipse.
 
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How do you know what you're seeing is bacteria?

Why wouldn't there be bacteria? One drop can contain hundreds of bacteria and if the image was expanded enough it may be obvious that they are indeed bacteria and not just debris.

If you take the lens off a laser and just let the light diverge, then take a hair and put it right in front of the diode lens it, the shadow will be magnified to a few inches across as it is projected on a nearby wall. You'll get alot of diffraction effects but it's still very clear to make out what you're looking at.

-Tony
 
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It's possible to use a laser as microscope, of sorts.

Behold in the image below, a common 75 watt incandescent light bulb

micro_bulb.jpg


I've circled the 'A' in 'SYLVANIA', which will get magnified in the next image.

To create the image below I slightly defocused my red laser brick (~80-100 mW). Next shine the laser spot onto the bulb from 3-4 meters away. The reflected spot then travels 1-2 meters, just above the sofa. The 'A' is now magnified 1-2 feet across. The curvature of the bulb provides the magnification.

micro_A.jpg


In the images below I'm shining the laser of the surface of the bulb. The images represent the surface of the bulb where the laser hits it (a few mm per side spot) blown up to several feet across. The interference patterns represent ripples and irregularities in the surface of the bulb, greatly magnified.

interference5.jpg

interference.jpg

interference2.jpg

interference3.jpg

interference4.jpg


I like the idea of magnifying any critters in a drop of pond water. I may try this.
 
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