Laser pointer discussion. Read/write reviews of laser pointers and laser pointer companies. Learn about all types of laser pointers and lasers





Welcome to Laser Pointer Forums! If you are looking for a laser pointer or want to compare different laser pointer companies, you may want to check out the LPF Laser Pointer Company Database. The link will open in a new window for your convenience.








Green Laser Pointers by Category Blue Laser Pointers by Category Red Laser Pointers by Category
Yellow Laser Pointers by Category Violet Laser Pointers by Category Orange Laser Pointers by Category
Top Laser Pointers by Power - 1 Watt+ Top Laser Pointers by Power - 500mW+ Top Laser Pointers by Power - 250mW+
Laser Pointer Database High Power Laser Pointers Laser Pointer Diodes
Laser Technology Laser Pointer Parts Lasers by Wavelength
Top 10 Laser Pointer Companies Laser Pointer Company Database Visible Beam Laser Pointers


One laser store meets all your needs

























Go Back   Laser Pointer Forums - Discuss Laser Pointers > Lasers > Tutorials, Help & Repairs



LPF List of Laser Pointer Companies (link opens new window)



Reply
 
LinkBack Thread Tools Display Modes
Old 09-10-2008, 10:00 PM #1
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Hodad Hodad is offline
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Default Is my green laser "near TEM00" or TEM10

I was trying to measuring the beam diameter of a 532nm DPSS laser and I noticed that the beam was more oval shaped than round. I guess no beam is perfectly round but this one looked borderline TEM10.

I'm having to view the spot through a digital camera (I have ML7 safety glasses on order from a recent GB but they won't be here for a while). The spot faintly resembled the attached image from a gaussian chart . I can't tell for sure though as the brightness of the spot was making it hard for the camera to focus, etc. If I can ever get the settings right I'll post an actual photo.

Is there any other (or better) way to determine what mode beam I have?

Attached Thumbnails
Is my green laser "near TEM00" or TEM10-tem10.jpg  


Hodad is offline   Reply With Quote







LPF List of Laser Pointer Companies (link opens new window)







Old 09-10-2008, 10:09 PM #2
Class 2 Laser
 
Join Date: Sep 2007
Posts: 464
Rep Power: 14
darklandz is just really nicedarklandz is just really nicedarklandz is just really nicedarklandz is just really nice
darklandz darklandz is offline
Class 2 Laser
 
Join Date: Sep 2007
Posts: 464
Rep Power: 14
darklandz is just really nicedarklandz is just really nicedarklandz is just really nicedarklandz is just really nice
Default Re: Is my green laser "near TEM00" or TEM10

shine your laser through a magnifying glass or any focusing lens and if the projected dot matches that of the image, its running in TEM01 mode.
darklandz is offline   Reply With Quote
Old 09-10-2008, 10:10 PM #3
daguin's Avatar
Super Moderator
 
Join Date: Mar 2008
Location: Sunny Southern California
Posts: 16,636
Rep Power: 1432
daguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond repute
daguin daguin is offline
Super Moderator
daguin's Avatar
 
Join Date: Mar 2008
Location: Sunny Southern California
Posts: 16,636
Rep Power: 1432
daguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond repute
Default Re: Is my green laser "near TEM00" or TEM10

Quote:
Originally Posted by Hodad
I was trying to measuring the beam diameter of a 532nm DPSS laser and I noticed that the beam was more oval shaped than round. *I guess no beam is perfectly round but this one looked borderline TEM10.

I'm having to view the spot through a digital camera (I have ML7 safety glasses on order from a recent GB but they won't be here for a while). *The spot faintly resembled the attached image from a gaussian chart . *I can't tell for sure though as the brightness of the spot was making it hard for the camera to focus, etc. *If I can ever get the settings right I'll post an actual photo.

Is there any other (or better) way to determine what mode beam I have?
Shine it through a magnifying glass onto a fairly close , flat surface.

Peace,
dave

**EDIT** Ditto
__________________
How To Get Along In and Be Accepted in the Forum

If you got some value out of reading this forum, how about donating $2 to keep it going?
Click Here to donate

Love all, trust a few, do wrong to none.
-William Shakespeare
daguin is offline   Reply With Quote
Old 09-11-2008, 02:31 AM #4
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Hodad Hodad is offline
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Default Re: Is my green laser "near TEM00" or TEM10

Thanks, I'll try that tomorrow. I'm getting to tired to be safe tonight.

I just read some "heavy" ;D material from Melles Griot about "Real Beam Propagation" : and now I'm more confused than ever.

All I halfway understood was this:

"The need for a figure of merit for laser beams that can be used to determine the propagation characteristics of the beam has long been recognized. Specifying the mode is inadequate, because, for example, the output of a laser can contain up to 50% higher order modes and still be considered TEM00."


Apparently, it goes on to suggest, the M[sup]2[/sup] is a better figure of merit to determine the qualities of a laser beam.

But I thought M[sup]2[/sup] was just a measure of how round the beam was.....

The specs say this laser is supposed to be "near TEM00" and M[sup]2[/sup] : <=2.0. But in light of the quote above. What does that mean?

All I really want to know is do I have a good beam or a not so good beam? Is it single mode (one beam?) or multi-mode (more than one beam?)

Just when I thought I had a grip on understanding it

Sorry, I'm just expressing my frustration at not being able to make sense of it.
Hodad is offline   Reply With Quote
Old 09-12-2008, 12:00 AM #5
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Hodad Hodad is offline
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Default Re: Is my green laser "near TEM00" or TEM10

Here are the pics I took of the beam spot with and without the suggested magnifying glass.

I posted multiple pics to show any change in the beam. They were taken over a 5-10 minute period. Does anyone see anything other than "near TEMoo" ?

This one is with magnifying glass
Attached Thumbnails
Is my green laser "near TEM00" or TEM10-p9112186.jpg  
Hodad is offline   Reply With Quote
Old 09-12-2008, 12:08 AM #6
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Hodad Hodad is offline
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Default Re: Is my green laser "near TEM00" or TEM10

and another
Attached Thumbnails
Is my green laser "near TEM00" or TEM10-p9112187.jpg  
Hodad is offline   Reply With Quote
Old 09-12-2008, 12:13 AM #7
FrothyChimp's Avatar
Class 2M Laser
 
Join Date: Sep 2007
Posts: 977
Rep Power: 80
FrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond repute
FrothyChimp FrothyChimp is offline
Class 2M Laser
FrothyChimp's Avatar
 
Join Date: Sep 2007
Posts: 977
Rep Power: 80
FrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond reputeFrothyChimp has a reputation beyond repute
Default Re: Is my green laser "near TEM00" or TEM10

That's near TEM00. Near TEM00 means the Gaussian curve expected in a single transverse mode is clipped across the top in some manner. It could be level, have a small dip in it or angled.
__________________
The Frothy Chimp
Cynic Extraordinaire
Why yes, I am a rocket scientist

Good whiskey, fine cigars, long legged women and blues guitar.
That's what I like.

The strong shall stand, the weak shall fall by the wayside.
FrothyChimp is offline   Reply With Quote
Old 09-12-2008, 12:17 AM #8
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Hodad Hodad is offline
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Default Re: Is my green laser "near TEM00" or TEM10

and another
Attached Thumbnails
Is my green laser "near TEM00" or TEM10-p9112188.jpg  
Hodad is offline   Reply With Quote
Old 09-12-2008, 12:18 AM #9
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Hodad Hodad is offline
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Default Re: Is my green laser "near TEM00" or TEM10

and the last one with magnifying glass. This is the one I thought the beam might be starting to "split" in.
i'm looking at the brighest part in the center, notice how it seems to have a dip in it.

Maybe thats what you are talking about FC. Or have you seen this one yet?
Attached Thumbnails
Is my green laser "near TEM00" or TEM10-p9112189.jpg  
Hodad is offline   Reply With Quote
Old 09-12-2008, 12:19 AM #10
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Hodad Hodad is offline
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Default Re: Is my green laser "near TEM00" or TEM10

this is without magnifying glass
Attached Thumbnails
Is my green laser "near TEM00" or TEM10-p9112199.jpg  
Hodad is offline   Reply With Quote
Old 09-12-2008, 12:20 AM #11
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Hodad Hodad is offline
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Default Re: Is my green laser "near TEM00" or TEM10

and the last one, (no magnifying glass).

Sorry I didn't get them all up until now. I thought I could post multiple images in one but I guess not.
Attached Thumbnails
Is my green laser "near TEM00" or TEM10-p9112200.jpg  
Hodad is offline   Reply With Quote
Old 09-12-2008, 12:41 AM #12
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Hodad Hodad is offline
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Default Re: Is my green laser "near TEM00" or TEM10

Here's an image of the spot on thermal paper. This was done right in front of the aperture. looks like TEM01*
on the Laguerre-gaussian chart.

Attached Thumbnails
Is my green laser "near TEM00" or TEM10-thermal.jpg  
Hodad is offline   Reply With Quote
Old 09-14-2008, 08:27 AM #13
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Hodad Hodad is offline
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Default I guess this thread may be dead

I guess my thread is old.
Hodad is offline   Reply With Quote
Old 09-14-2008, 01:36 PM #14
daguin's Avatar
Super Moderator
 
Join Date: Mar 2008
Location: Sunny Southern California
Posts: 16,636
Rep Power: 1432
daguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond repute
daguin daguin is offline
Super Moderator
daguin's Avatar
 
Join Date: Mar 2008
Location: Sunny Southern California
Posts: 16,636
Rep Power: 1432
daguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond reputedaguin has a reputation beyond repute
Default Re: I guess this thread may be dead

Quote:
Originally Posted by Hodad
I guess my thread is old. *
You received the answer from FrothyChimp

Peace,
dave
__________________
How To Get Along In and Be Accepted in the Forum

If you got some value out of reading this forum, how about donating $2 to keep it going?
Click Here to donate

Love all, trust a few, do wrong to none.
-William Shakespeare
daguin is offline   Reply With Quote
Old 09-14-2008, 03:07 PM #15
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Hodad Hodad is offline
Class 1 Laser
 
Join Date: Jul 2008
Posts: 67
Rep Power: 10
Hodad is on a distinguished road
Default Re: I guess this thread may be dead

Quote:
Originally Posted by daguin
[quote author=Hodad link=1221084038/0#12 date=1221380854]I guess my thread is old.
You received the answer from FrothyChimp

Peace,
dave[/quote]

I know, and I was very happy about his confirmation that it was near TEM00. He has answered many of my questions and been of tremendous help to me. But I had not posted the latest image until after he responded with the answer.

BTW -thanks again FrothyChimp. You always come through!

Hodad 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











Loading








Green Laser Pointers by Category Blue Laser Pointers by Category Red Laser Pointers by Category
Yellow Laser Pointers by Category Violet Laser Pointers by Category Orange Laser Pointers by Category
Top Laser Pointers by Power - 1 Watt+ Top Laser Pointers by Power - 500mW+ Top Laser Pointers by Power - 250mW+
Laser Pointer Database High Power Laser Pointers Laser Pointer Diodes






Privacy Policy | Advertising Disclaimer | Terms of Use


 


All times are GMT. The time now is 01:50 PM.


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