Old 03-01-2011, 09:11 PM #1
Fivos's Avatar
Class 1 Laser
 
Join Date: Sep 2010
Location: Athens, Greece
Posts: 54
Rep Power: 8
Fivos is on a distinguished road
Fivos Fivos is offline
Class 1 Laser
Fivos's Avatar
 
Join Date: Sep 2010
Location: Athens, Greece
Posts: 54
Rep Power: 8
Fivos is on a distinguished road
Post Laser Divergence Info

Laser Divergence Calculator
Example of an almost accurate aligned laser. A 473nm 50mw laser..
Divergence: 1.2mrad


Hope you liked my project...
__________________________________________________ _________________
Warning: VERY BAD ENGLISH...



Last edited by Fivos; 03-01-2011 at 09:14 PM.
Fivos is offline   Reply With Quote


















Old 03-01-2011, 09:49 PM #2
Cyparagon's Avatar
Class 4 Laser
 
Join Date: Sep 2007
Location: Wisconsin
Posts: 9,292
Rep Power: 199036
Cyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond repute
Cyparagon Cyparagon is online now
Class 4 Laser
Cyparagon's Avatar
 
Join Date: Sep 2007
Location: Wisconsin
Posts: 9,292
Rep Power: 199036
Cyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond repute
Default Re: Laser Divergence Info

I like working with ones better. Here's something a little more simple. If a laser diverges 1mm in 1m, the tangent of the angle would be equal to 1/1000:

tan θ = 1/1000
θ = arctan(0.001)
θ = 0.0009999 = 0.001rad = 1mrad

Follow the steps backward to see that 2mrad just means it diverges 2mm for every meter.
__________________
A problem well stated is a problem half solved.
Cyparagon is online now   Reply With Quote
Old 03-01-2011, 10:34 PM #3
DrSid's Avatar
Class 3R Laser
 
Join Date: Jul 2010
Location: Olomouc, Czech Republic
Posts: 1,516
Rep Power: 153
DrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond repute
DrSid DrSid is offline
Class 3R Laser
DrSid's Avatar
 
Join Date: Jul 2010
Location: Olomouc, Czech Republic
Posts: 1,516
Rep Power: 153
DrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond repute
Default Re: Laser Divergence Info

Doing arctan of angles bellow 1 degree is redundant. It results in almost the same number.
__________________
200mw (35mw compared) FocalPrice cheap green AA - Review
500mw (estimated) 445nm Minimalistic Orange Emos Direct Drive. Thread
1500mw (estimated) 445nm Jayrob's Solarforce L2P. Review
DrSid is offline   Reply With Quote
Old 03-01-2011, 11:15 PM #4
chipdouglas's Avatar
Class 3B Laser
 
Join Date: Dec 2008
Location: Riverside, California
Posts: 4,011
Rep Power: 1444
chipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond repute
Send a message via Yahoo to chipdouglas
chipdouglas chipdouglas is offline
Class 3B Laser
chipdouglas's Avatar
 
Join Date: Dec 2008
Location: Riverside, California
Posts: 4,011
Rep Power: 1444
chipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond reputechipdouglas has a reputation beyond repute
Send a message via Yahoo to chipdouglas
Default Re: Laser Divergence Info

Quote:
Originally Posted by DrSid View Post
Doing arctan of angles bellow 1 degree is redundant. It results in almost the same number.

I am probably the worst person at math here but if the numbers are "almost" the same, how is it redundant?
i'm not being a smart ass. just looking for an explanation.
__________________
IN A CONSTANT STATE OF PICNIC

I AM THE STATUS QUO

ARE YOU A NEW MEMBER, OR EVEN MORE, ARE YOU NEW TO ONLINE FORUMS... READ THIS
LASER POINTER FORUM ETIQUETTE


for pot modding facts click below

http://laserpointerforums.com/f51/pot-modding-faqs-40510.html
chipdouglas is offline   Reply With Quote
Old 03-02-2011, 12:35 AM #5
DrSid's Avatar
Class 3R Laser
 
Join Date: Jul 2010
Location: Olomouc, Czech Republic
Posts: 1,516
Rep Power: 153
DrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond repute
DrSid DrSid is offline
Class 3R Laser
DrSid's Avatar
 
Join Date: Jul 2010
Location: Olomouc, Czech Republic
Posts: 1,516
Rep Power: 153
DrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond repute
Default Re: Laser Divergence Info

Quote:
Originally Posted by chipdouglas View Post
I am probably the worst person at math here but if the numbers are "almost" the same, how is it redundant?
i'm not being a smart ass. just looking for an explanation.
It's redundant for most uses .. the difference is too small. For laser divergence for example it's irrelevant if it is 0.001 or 0.00997.
So if you make one measurement of beam diameter at large distance, all you need for divergence is size/distance (both in same units, result in radians).
__________________
200mw (35mw compared) FocalPrice cheap green AA - Review
500mw (estimated) 445nm Minimalistic Orange Emos Direct Drive. Thread
1500mw (estimated) 445nm Jayrob's Solarforce L2P. Review
DrSid is offline   Reply With Quote
Old 03-02-2011, 01:35 PM #6
Fivos's Avatar
Class 1 Laser
 
Join Date: Sep 2010
Location: Athens, Greece
Posts: 54
Rep Power: 8
Fivos is on a distinguished road
Fivos Fivos is offline
Class 1 Laser
Fivos's Avatar
 
Join Date: Sep 2010
Location: Athens, Greece
Posts: 54
Rep Power: 8
Fivos is on a distinguished road
Default Re: Laser Divergence Info

I didn't know. I'll do some more tests....Thanks...
Fivos is offline   Reply With Quote
Old 03-02-2011, 09:55 PM #7
Cyparagon's Avatar
Class 4 Laser
 
Join Date: Sep 2007
Location: Wisconsin
Posts: 9,292
Rep Power: 199036
Cyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond repute
Cyparagon Cyparagon is online now
Class 4 Laser
Cyparagon's Avatar
 
Join Date: Sep 2007
Location: Wisconsin
Posts: 9,292
Rep Power: 199036
Cyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond reputeCyparagon has a reputation beyond repute
Default Re: Laser Divergence Info

Good point, Dr. Sid. I was going to add that, but I forgot.



You'll see that for values close to zero, the graph of tangent is virtually linear. That is to say y ≈ x.
tan θ ≈ θ

The same is true of sine.
__________________
A problem well stated is a problem half solved.

Last edited by Cyparagon; 03-02-2011 at 09:57 PM.
Cyparagon is online now   Reply With Quote
Old 03-02-2011, 10:22 PM #8
DrSid's Avatar
Class 3R Laser
 
Join Date: Jul 2010
Location: Olomouc, Czech Republic
Posts: 1,516
Rep Power: 153
DrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond repute
DrSid DrSid is offline
Class 3R Laser
DrSid's Avatar
 
Join Date: Jul 2010
Location: Olomouc, Czech Republic
Posts: 1,516
Rep Power: 153
DrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond reputeDrSid has a reputation beyond repute
Default Re: Laser Divergence Info

I use different explanation. And that is: what does radian actually mean ? Well .. it measures the 'arc'. If you take pie section of radius 1, its curved side will be of the same length as the angle of the pie in radians. Full circle will be 2*pi.
Now imagine very thin pie section .. it's clear that the curvature has little effect on the length of the side opposite to the angle. Also as the central angle gets small, the other two angles are getting close to 90 degrees. So all height of the triangle, length of the arc, and length of the side opposing the central angle are becoming very similar .. and equal to angle in radians itself.
__________________
200mw (35mw compared) FocalPrice cheap green AA - Review
500mw (estimated) 445nm Minimalistic Orange Emos Direct Drive. Thread
1500mw (estimated) 445nm Jayrob's Solarforce L2P. Review
DrSid is offline   Reply With Quote
Reply





Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

























Privacy Policy | Advertising Disclaimer | Terms of Use


 


All times are GMT. The time now is 08:57 AM.


Powered by: vBulletin
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO
Privacy Policy | Advertising Disclaimer | Terms of Use
Copyright (C) 2017 Laser Pointer Forums, LLC