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ArcticMyst Security by Avery

Blue ray focus and dot

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I know there are lots of other posts about focusing blue rays but it seams that to get a decent dot a few meters away I have to remove the metal cap and screw the plastic lens down inside the module. Is that the case with blue rays?

Another thing I noticed is when its focused I get a small tiny dot with a sort of rectangle under it, is that normal? and last thing, is it worth trimming the plastic part to let more light through?
 





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you may have not pressed that diode all the way in causing it kinda hard to get the focus correct

prh 803-t's are rectangular yep, and yea its worth trimming that plastic baby!!!!!!!!!

this is only my opinion ;D
 
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john lawson said:
you may have not pressed that diode all the way in causing it kinda hard to get the focus correct

prh 803-t's are rectangular yep, and yea its worth trimming that plastic baby!!!!!!!!!

this is only my opinion ;D

Theres no way the diode is going in the module any more, its level with the bottom of the module.

How should I trim the plastic? just make it like the opposite end? and does it really make much of a difference?
 

daguin

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It needs to be pressed in until it is recessed into the module, NOT "flush."

At the output you are working with, opening the back of the lens nut won't give you an apparent increase in brightness.  The small hole in the back of the lens nut helps to make the beam look more "round."

Oh yeah -- the "stuff" around the beam is normal for many of these diodes.

Peace,
dave
 
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daguin said:
It needs to be pressed in until it is recessed into the module, NOT "flush."

At the output you are working with, opening the back of the lens nut won't give you an apparent increase in brightness.  The small hole in the back of the lens nut helps to make the beam look more "round."

Oh yeah -- the "stuff" around the beam is normal for many of these diodes.

Peace,
dave

Really? I just assumed they were meant to be flush like red diodes... or that's how I have always done it. How can I get it inside like that? I just used the back end of the module as a press.
 

daguin

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lamborgini8 said:
[quote author=daguin link=1234649201/0#3 date=1234651237]It needs to be pressed in until it is recessed into the module, NOT "flush."
At the output you are working with, opening the back of the lens nut won't give you an apparent increase in brightness.  The small hole in the back of the lens nut helps to make the beam look more "round."
Oh yeah -- the "stuff" around the beam is normal for many of these diodes.
Peace,
dave
Really? I just assumed they were meant to be flush like red diodes... or that's how I have always done it. How can I get it inside like that? I just used the back end of the module as a press.[/quote]


Actually, red diodes SHOULD be pressed until they are recessed as well.  Fortunately for red diodes the focal length for them is farther away so the are still OK if they are not fully pressed into the module.  Violet diodes have a shorter focal length so the lens has to be closer to the diode to focus it up close

Different people use different "tools" to get the diode pressed in all the way.  Wannaburn made some.  Some people use the end of a 1/4" air hose fitting.  Some use the adjusting "screw" from a bicycle brake cable.  Some people have made their own.  You just need something that is hollow enough for the pins to fit up inside it and smaller than 5.6mm in diameter

Here's one of Rog's great drawings to show the idea
insert_LD_correctly.jpg


Peace,
dave
 
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I will post both pictures again...
It is worth noting that by pressing all the way in thermal contact with the module is greatly improved.

insertLDcorrectly.jpg


Regards rog8811
 

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Ah right, il see what I can find tomorrow.

Does the last half a millimeter make much a difference at all though?
 
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When you consider that around 10 degrees of lens rotation will take you through focus and out the other side pushing the LD in another mm will make a great deal of difference as that is more than a full turn of the lens.

Regards rog8811
 
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lamborgini8 said:
Ah right, il see what I can find tomorrow.

Does the last half a millimeter make much a difference at all though?


;)oh yea just ask my wife every mm counts :-X ;D ;D
 
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john lawson said:
[quote author=lamborgini8 link=1234649201/0#9 date=1234654472]Ah right, il see what I can find tomorrow.

Does the last half a millimeter make much a difference at all though?
 

;)oh yea just ask my wife every mm counts  :-X ;D ;D[/quote]

ROFLLLLLLL
 
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john lawson said:
you may have not pressed that diode all the way in causing it kinda hard to get the focus correct

prh 803-t's are rectangular yep, and yea its worth trimming that plastic baby!!!!!!!!!

this is only my opinion ;D

You can also pull the plastic part out instead of cutting it...Well at least mine did allow me to do it.

--hydro15
 




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