Polygon mirror Drum

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Polygon mirror Drum

Postby Harry Dalek » Sat Nov 26, 2022 10:56 pm

I have always been a fan of Alan Shorts NBTV work in the newsletters ,getting close to a good 30 years now and i always liked the way he thinks the designs using the polygon mirror drums idea.

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Pretty much a finite number of straight line segments connected to form a closed polygonal chain so like standard mirror drum with out the slight mirror tilt for each mirror here they are all the same and light spot all light lines should over lap ,(my mirror drum really need to double count 43 or 44 mirrors) pretty much the size of my mirrors and what fitted on my drum used what i had ! more the better for this system and i will be using something else for framing side of it ,thinking still what i will do here .

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The motor side adjusted again with what i had for the pulley belt

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Felt like a little mechanical work and so looking into similar design with pretty much as always what i have laying around i did buy these mirrors a number of years ago for a future mirror drum .

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Well onto construction the problem with all mirror drums is how to mount the mirrors and stopping them flying off the drum ! ,here the mirrors have a paper plastic glue backing so rather easy to mount the strip of mirrors around the drum so next was stopping them flying off with centrifugal force ,i used 2 pulley belts to hold the mirrors in place ,since i just need a thin mirror strip not much of the mirrors are needed viewable i put 2 strips of mirrors just because they fitted and holds the mirrors on the drum better than a single strip .
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Last edited by Harry Dalek on Sun Nov 27, 2022 8:31 am, edited 1 time in total.
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Harry Dalek
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Re: Polygon mirror Drum

Postby Harry Dalek » Sat Nov 26, 2022 11:50 pm

Here testing with a quick laser knock up just to see how the mirrors are lining up , any thing under the mirrors to throw the mirrors off ...Never glue under them !

BTW i am using a scrapped U matic video drum from the early 70s for the drum and another video head for the spacer on the motor side .



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The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5364
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: Polygon mirror Drum

Postby Harry Dalek » Sun Nov 27, 2022 7:13 pm

Today i was working on screen and laser position same on the framing side either going with a rocking mirror or rotating 4 sided little drum, so lot more to do but idea coming together .
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The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5364
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: Polygon mirror Drum

Postby Harry Dalek » Fri Dec 02, 2022 3:29 pm

This is a learning exercise here to see if i can get a working proof of concept ,tried similar ideas in the past with far fewer line mirrors .
Looking into my screen i noticed its not 100% flat so as a screen gives a slight wavy effect to the raster line nothing to worry to much about but live and learn .
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So mounted the laser today ,i was thinking of trying a luxeon or a bank of them and seeing if i could focusing it but it would of made the project much longer laser is so much easier on the optics side



Now that's the concept over with for the wanted scanning movements
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The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5364
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia


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