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 > Optics



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



Reply
 
LinkBack Thread Tools Display Modes
Old 01-17-2011, 06:23 AM #1
Junior Member
 
Join Date: Dec 2010
Posts: 3
Rep Power: 0
jJack is on a distinguished road
jJack jJack is offline
Junior Member
 
Join Date: Dec 2010
Posts: 3
Rep Power: 0
jJack is on a distinguished road
Lightbulb Pinhole for laser diode

Hello, I am an active participant since 3 months now.
I am building a set-up to reduce my beam size from 3mm to 1 micron. I used a large combinations of lenses but always had issues in size. So i decided to use a 1 micron pinhole. I want to ask for an expertise to know if it works.
Should i converge the beam a little and then put the pinhole?

Thanks in advance


jJack is offline   Reply With Quote







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







Old 01-17-2011, 01:09 PM #2
LazyBeam's Avatar
Class 2 Laser
 
Join Date: Jun 2010
Posts: 446
Rep Power: 24
LazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant future
LazyBeam LazyBeam is offline
Class 2 Laser
LazyBeam's Avatar
 
Join Date: Jun 2010
Posts: 446
Rep Power: 24
LazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant future
Default Re: Pinhole for laser diode

Wha kind of power density do you need?
What kind of divergence?

The reason I ask is that you'll lose alot of power if you just attenuate the beam.

Lets assume you are using a 300mW beam with a diameter of 1mm. To simply shine that laser through a 1 micron hole would reduce your power by about factor of 1 milion (1 square millimeter is about 1 million times more area than 1 square micron). So you'd end up with a 300nW (nanowatt) beam.

Keep in mind that when you optically reduce beam size you also increase the divergnce of the beam because beam diameter and divergence are inversely proportional. A 1mm 0.5mrad beam (this is an excellent beam) entering a 1000X beam reducer will give a 1um exit beam but the divergence would be 500mrad. Every meter your micron beam travels, the diameter of the beam will diverge 500mm (terrible, like a flashlight). Also your lens contours would have to be crazy-accurate to produce beams around 1-3 wavelengths in diameter.

Also, you're starting to approch visible wavelength of light. 1 micron is 1000 nanomaters. As you approach the wavelength of your light you will begin to experience interesting phenominon with your light. Particularly, diffraction patterns will emmerge due to light displaying wave behavior as it passes throught apertures small relative to the wavelength of light.
__________________
Wicked Lasers - E1 Executive Fusion - 5mW - 532nm
Custom Build - Dual Power AW210 Pen Style Pointer - 40mW/180mW - 405nm (Click for Pics!)
Custom Build - SF-AW210 in $1 AA/14500 Host - 150mW - 405nm (Click for Pics!)
Custom Build - "AA" Pocket Host - 650mW - 445nm (almost complete) (Click for Pics!)

Last edited by LazyBeam; 01-17-2011 at 01:15 PM.
LazyBeam is offline   Reply With Quote
Old 01-17-2011, 03:28 PM #3
benmwv's Avatar
Class 3R Laser
 
Join Date: Sep 2010
Location: wv
Posts: 1,389
Rep Power: 152
benmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond repute
benmwv benmwv is offline
Class 3R Laser
benmwv's Avatar
 
Join Date: Sep 2010
Location: wv
Posts: 1,389
Rep Power: 152
benmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond reputebenmwv has a reputation beyond repute
Default Re: Pinhole for laser diode

I dont think divergence would be a problem because this is passing through a pin hole and not a beam reducer.

The set up he had used before with all the lenses would have definitely had that problem though.

You are right about the power, it will be greatly reduced.
benmwv is offline   Reply With Quote
Old 01-17-2011, 03:32 PM #4
LazyBeam's Avatar
Class 2 Laser
 
Join Date: Jun 2010
Posts: 446
Rep Power: 24
LazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant future
LazyBeam LazyBeam is offline
Class 2 Laser
LazyBeam's Avatar
 
Join Date: Jun 2010
Posts: 446
Rep Power: 24
LazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant futureLazyBeam has a brilliant future
Default Re: Pinhole for laser diode

What do you even do with a nanowatt range beam?

There's more excitation when I walk into a room full of women than there is involved with a nanowatt-scale laser... and I'm not a good looking guy.
__________________
Wicked Lasers - E1 Executive Fusion - 5mW - 532nm
Custom Build - Dual Power AW210 Pen Style Pointer - 40mW/180mW - 405nm (Click for Pics!)
Custom Build - SF-AW210 in $1 AA/14500 Host - 150mW - 405nm (Click for Pics!)
Custom Build - "AA" Pocket Host - 650mW - 445nm (almost complete) (Click for Pics!)
LazyBeam is offline   Reply With Quote
Old 01-17-2011, 03:46 PM #5
Cyparagon's Avatar
Class 4 Laser
 
Join Date: Sep 2007
Location: Wisconsin
Posts: 9,144
Rep Power: 9321
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: 9,144
Rep Power: 9321
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: Pinhole for laser diode

Quote:
Originally Posted by jJack View Post
I am building a set-up to reduce my beam size from 3mm to 1 micron.
Why? See sig.
__________________
A problem well stated is a problem half solved.
Cyparagon is online now   Reply With Quote
Old 01-17-2011, 04:28 PM #6
3zuli's Avatar
Class 2M Laser
 
Join Date: May 2009
Location: SVK
Posts: 811
Rep Power: 37
3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute
3zuli 3zuli is offline
Class 2M Laser
3zuli's Avatar
 
Join Date: May 2009
Location: SVK
Posts: 811
Rep Power: 37
3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute3zuli has a reputation beyond repute
Default Re: Pinhole for laser diode

do you need the beam to have 1um on the full length, or do you just need a spot with 1um diameter? in the second case, you need just a colimating lens and some accurate adjustment mount which will allow you to set the smallest spot size.
__________________
<< that's not me


some 5mW pointers
LPC-815 "mini labby" @ 350mA

SLD63518262 5mW 635nm
DX 5mW
DX 50mW
DX 30mW module in spirograph link
DX 50mW in modded LAS-7 spirograph link

445nm 800mW link
PHR-803T @ 105mA in DildaV2 kit link
3zuli is offline   Reply With Quote
Old 01-17-2011, 11:28 PM #7
Benm's Avatar
Class 4 Laser
 
Join Date: Aug 2007
Location: Netherlands
Posts: 7,440
Rep Power: 18210
Benm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond repute
Benm Benm is online now
Class 4 Laser
Benm's Avatar
 
Join Date: Aug 2007
Location: Netherlands
Posts: 7,440
Rep Power: 18210
Benm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond repute
Default Re: Pinhole for laser diode

A micron sized dot or beam waist?!

One micron is just under 2 wavelengths when working with 532 nm light, and will definitely give you interesting particle-wave duality effects, but not a micron-wide beam at all.

What actually would happen is this: The pinhole would act as a new point of origin for the beam coming out on the other side. This would be spread over almost a complete half sphere, with a gaussian distribution favouring the forward direction.

Optics may work to shrink a beam down to 10 microns or so at a given focal length, but beyond that things get complicated.

If you would state your goal with doing all this, perhaps we could provide some more insight.
Benm is online now   Reply With Quote
Old 01-18-2011, 02:46 PM #8
Junior Member
 
Join Date: Dec 2010
Posts: 3
Rep Power: 0
jJack is on a distinguished road
jJack jJack is offline
Junior Member
 
Join Date: Dec 2010
Posts: 3
Rep Power: 0
jJack is on a distinguished road
Default Re: Pinhole for laser diode

Commercially there are no laser sources with 1 micron and less than 1mw power, which is the target. The application is correctly for low power application.
So I bought a laser diode module with 3mw (best i could get), 0.203mrad divergence, 650nm wavelength and around 4 mm waist diameter at the tip of diode. I thought I can reduce its size to 1micron using lenses.
I simulated the beam in a software, reducing the size step by step in 3 stages. Since i have to maintain the divergence angle ... the smallest spot i could get and almost collimated was 10 micron.

The application is for MEMS devices which are of the order of 100microns in size.
The beam hits the device, reflects and strikes a detector. So its like a beam falls on the mirror at an angle and gets reflected. The reflected beam is made to strike a light detector. The total length of light travel, starting from the laser diode is estimated to be within 200 -300mm.

I like to thank for all the replies. But I am seriously working on this project for 3 months now and searching for help.
jJack is offline   Reply With Quote
Old 01-18-2011, 03:25 PM #9
Cyparagon's Avatar
Class 4 Laser
 
Join Date: Sep 2007
Location: Wisconsin
Posts: 9,144
Rep Power: 9321
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: 9,144
Rep Power: 9321
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: Pinhole for laser diode

1 micron is a stretch for a focal point. Making a beam that small is virtually impossible. If you only need it to be 1 micron at two points, you might be able to focus it twice instead.
__________________
A problem well stated is a problem half solved.
Cyparagon is online now   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 07:33 AM.


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