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 > Laser Shows



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



Reply
 
LinkBack Thread Tools Display Modes
Old 10-27-2010, 02:59 PM #129
sltvm2007's Avatar
Class 1 Laser
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
sltvm2007 sltvm2007 is offline
Class 1 Laser
sltvm2007's Avatar
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
Default Re: Homemade Scanning Laser Color Projector/TV

You just adjust the max value of the current to be the Imax of the laser diode.

If the video signal becomes too high somewhere while experimenting, power supply will fail to supply current greater than Imax. It is that simple.

After finding the critical values of all parameters you may replace yor source with a constant Vcc.

Sorry, English is not my mother language. Maybe I cannot express myself correctly.

Edit: The current limitting power supply in that picture is not a DDL. It can deliver any current below the limitting value to the circuit

picture is on page5 post 124



Last edited by sltvm2007; 10-27-2010 at 04:08 PM.
sltvm2007 is offline   Reply With Quote







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







Old 10-27-2010, 09:13 PM #130
Class 2M Laser
 
Join Date: May 2009
Posts: 955
Rep Power: 1542
LSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond repute
LSRFAQ LSRFAQ is offline
Class 2M Laser
 
Join Date: May 2009
Posts: 955
Rep Power: 1542
LSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond repute
Default Re: Homemade Scanning Laser Color Projector/TV

[QUOTE=sltvm2007;808221]Reply to kingbower and dasraiser


Contrary to the common belief, DPSS green lasers are susceptible to high speed analog modulation.

Not quite right at all.

Only at very low powers, on the order of a few mW. Only in lasers where the pump diode is so small, it sees a infinite heat sink.

Steve
LSRFAQ is offline   Reply With Quote
Old 10-27-2010, 09:22 PM #131
Class 2M Laser
 
Join Date: May 2009
Posts: 955
Rep Power: 1542
LSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond repute
LSRFAQ LSRFAQ is offline
Class 2M Laser
 
Join Date: May 2009
Posts: 955
Rep Power: 1542
LSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond reputeLSRFAQ has a reputation beyond repute
Default Re: Homemade Scanning Laser Color Projector/TV

quote

Contrary to the common belief, DPSS green lasers are susceptible to high speed analog modulation.

end quote.

Not quite right at all.

Only at very low powers, on the order of a few tens of mW. Only in small DPSS lasers where the pump diode is so small, it sees a infinite heat sink and thus does not shift in wavelength much, and where thermal distortion in the ND:Yag is low. Because he is showing video, he has a moderately constant average power and the laser is somewhat thermally stable. If he had to wrench the diode from blanked to full on at high powers, he would see the same modulation problems the rest of us have.

In other words, it does not scale to large scale displays beyond a few tens of milliwatts.


As for the power supply,

What he is trying to say is he has a constant current driver with good compliance and then mounts a series modulating transistor in the cathode of the diode. He is then lucky that he is operating in the moderate current, some what linear regions with his diodes. You then have to very carefully adjust the base current of the transistor to get it in its linear region. Fine for a one off in the lab, but hell to manufacture commercially.

No emitter degeneration, no feedback, no Miller effect compensation, and if you looked at the diode current on a scope, its ringing like mad. If you try this, keep the cables VERY short and the currents to the diode low. If you want to do it better, place the transistor in shunt across the laser diode, with a small series RC for degeneration in the emitter lead, and invert the video. This way the constant current source does not see wild fluctuations and is less likely to spike, ring, or oscillate.


Steve

Last edited by LSRFAQ; 10-27-2010 at 09:31 PM.
LSRFAQ is offline   Reply With Quote
Old 10-27-2010, 09:53 PM #132
Member
 
Join Date: Feb 2010
Posts: 31
Rep Power: 0
kingbowser is on a distinguished road
kingbowser kingbowser is offline
Member
 
Join Date: Feb 2010
Posts: 31
Rep Power: 0
kingbowser is on a distinguished road
Default Re: Homemade Scanning Laser Color Projector/TV

These are the problems I was talking about ;-)

The modulation of green lasers is far from simple. What is the maximum output of the green laser you used for the previous screen shots?
kingbowser is offline   Reply With Quote
Old 10-28-2010, 08:26 AM #133
sltvm2007's Avatar
Class 1 Laser
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
sltvm2007 sltvm2007 is offline
Class 1 Laser
sltvm2007's Avatar
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
Default Re: Homemade Scanning Laser Color Projector/TV

Reply to dasraiser:

I forgot to say, if there is any built in elecronics in your green laser, such as DDL, you should take it out.

There is a picture of the lasers below, used in this scanner :

For some pictures and more info:
http://laserpointerforums.com/member...laser-scanner/

Homemade Scanning Laser Color Projector/TV

Kuntman's Color Projector/ TV:
YouTube - Laser TV - Projector (no-MEMS, no AOM)

3D Visual Effect by Kuntman's Scanner:
YouTube - 3D Visual Effect (Kuntman's Scanner, Laser Projector/TV)

Videos:
YouTube - homemade laser projector tv (no-MEMS, no-AOM)

YouTube - laser tv (without MEMS)
Attached Thumbnails
Homemade Scanning Laser Color Projector/TV-green-lasers.jpg  

Last edited by sltvm2007; 10-28-2010 at 09:04 AM.
sltvm2007 is offline   Reply With Quote
Old 10-29-2010, 05:56 AM #134
Member
 
Join Date: Feb 2010
Posts: 31
Rep Power: 0
kingbowser is on a distinguished road
kingbowser kingbowser is offline
Member
 
Join Date: Feb 2010
Posts: 31
Rep Power: 0
kingbowser is on a distinguished road
Default Re: Homemade Scanning Laser Color Projector/TV

What is the maximum power you feed the green laser? When you plan to add the blue (or violet) channel? In these days the 445 nm blue ones from Casio projector are quite simple to find, and a 405 nm one I think would do it too.
kingbowser is offline   Reply With Quote
Old 10-29-2010, 08:10 AM #135
sltvm2007's Avatar
Class 1 Laser
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
sltvm2007 sltvm2007 is offline
Class 1 Laser
sltvm2007's Avatar
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
Default Re: Homemade Scanning Laser Color Projector/TV

Quote:
Originally Posted by kingbowser View Post
What is the maximum power you feed the green laser?
what do you mean by ''feed in max power''?
Are you asking about the video amp?
sltvm2007 is offline   Reply With Quote
Old 10-29-2010, 09:32 AM #136
Member
 
Join Date: Feb 2010
Posts: 31
Rep Power: 0
kingbowser is on a distinguished road
kingbowser kingbowser is offline
Member
 
Join Date: Feb 2010
Posts: 31
Rep Power: 0
kingbowser is on a distinguished road
Default Re: Homemade Scanning Laser Color Projector/TV

Yes, how many milliwatts you are using
kingbowser is offline   Reply With Quote
Old 10-29-2010, 06:30 PM #137
sltvm2007's Avatar
Class 1 Laser
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
sltvm2007 sltvm2007 is offline
Class 1 Laser
sltvm2007's Avatar
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
Default Re: Homemade Scanning Laser Color Projector/TV

Video amp of that green laser circuit was designed and made by one of my students when I was working for the university. Nevertheless, I have a look at the board. There used NE592 as a video amp and it drives a transistor (BC 140) with a small heatsink. You may estimate the input power from the datasheet of these components.

But before experimenting, you need a high speed XY scanner synchronized to the video. Otherwise you have no means to see what is going on.

The common belief ''green lasers cannot be modulated'' comes mainly from the lack of such an instrument. You cannot find the critical values of the parameters shown in that diagram, unless you are monitoring the image scanned by a suitable projector. Because that parameters all depend on the characteristics of a particular laser.

At the beginning you may see no sign of modulation. But when you come closer to the critical values a blurred image will appear. And the rest will follow immediately.
sltvm2007 is offline   Reply With Quote
Old 10-31-2010, 06:02 AM #138
Member
 
Join Date: Feb 2010
Posts: 31
Rep Power: 0
kingbowser is on a distinguished road
kingbowser kingbowser is offline
Member
 
Join Date: Feb 2010
Posts: 31
Rep Power: 0
kingbowser is on a distinguished road
Default Re: Homemade Scanning Laser Color Projector/TV

So you are saying that if you use a fast mpdulation you won't have the problems of the "slow" modulation? It's interesting.
kingbowser is offline   Reply With Quote
Old 10-31-2010, 08:57 AM #139
sltvm2007's Avatar
Class 1 Laser
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
sltvm2007 sltvm2007 is offline
Class 1 Laser
sltvm2007's Avatar
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
Default Re: Homemade Scanning Laser Color Projector/TV

Reply to kingbowser and LASERFAQ,

That may be right: What is imposible in slow modulation somehow turns out to be possible in fast modulation. Perhaps the answer is hidden in the physics of the crystal. As noted by LASERFAQ :
''...where thermal distortion in the ND:Yag is low. Because he is showing video, he has a moderately constant average power and the laser is somewhat thermally stable.''

Let me try to make this point clear:
In order to see what happens, consider a square wave modulation: At low frequencies, average power calculated in successive time intervals ''t'' (1 ms for instance) will not be equal (constant), if ''t'' is smaller than the period ''T'' of the square wave. ( ''t'' is assumed to be long enough that the temparature of the crystal undergoes great fluctuations during that period.)

But if we increase the frequency of the square wave so that ''T'' becomes very small than ''t'', average power calculated in succesive time intervals of ''t'' become almost equal.

In our case ''T'' is in the order of 0.1microseconds. And hence, the crystal can be considered thermally stable, provided that video content does not undergo drastic changes.

It is clear that, same explanation does apply to the modulation of green lasers of any power. Therefore fast modulation of green lasers is no way limitted to 0.1 mW range. Avatar of the present thread is an evidence of this. That picture was taken from an image of dimensions 20x30 cm performed on a screen 35 cm away from the scanner by a 50 mW green laser . And in the video in youtube you may see that the image is still visible under 200 watt spot lights!

Last edited by sltvm2007; 10-31-2010 at 08:00 PM.
sltvm2007 is offline   Reply With Quote
Old 11-09-2010, 09:03 PM #140
Bionic-Badger's Avatar
Class 4 Laser
 
Join Date: Oct 2007
Location: Oregon, USA
Posts: 5,478
Rep Power: 1792
Bionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond repute
Bionic-Badger Bionic-Badger is online now
Class 4 Laser
Bionic-Badger's Avatar
 
Join Date: Oct 2007
Location: Oregon, USA
Posts: 5,478
Rep Power: 1792
Bionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond reputeBionic-Badger has a reputation beyond repute
Default Re: Homemade Scanning Laser Color Projector/TV

Sorry if this has been explained, but your diagrams show the mirror strip for the fast axis, but what are you using for the slow axis?
Bionic-Badger is online now   Reply With Quote
Old 11-12-2010, 12:32 PM #141
sltvm2007's Avatar
Class 1 Laser
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
sltvm2007 sltvm2007 is offline
Class 1 Laser
sltvm2007's Avatar
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
Default Re: Homemade Scanning Laser Color Projector/TV

Slow axis is not critical, any galvo can be used for the slow axis.
The simplest one is a high torque galvo, driven sinusoidally with a suitable time delay and flyback blanking.

For some pictures and more info:
http://laserpointerforums.com/member...laser-scanner/

Homemade Scanning Laser Color Projector/TV

Kuntman's Color Projector/ TV:
YouTube - Laser TV - Projector (no-MEMS, no AOM)

3D Visual Effect by Kuntman's Scanner:
YouTube - 3D Visual Effect (Kuntman's Scanner, Laser Projector/TV)

Videos:
YouTube - homemade laser projector tv (no-MEMS, no-AOM)

YouTube - laser tv (without MEMS)

Last edited by sltvm2007; 11-25-2010 at 04:41 AM.
sltvm2007 is offline   Reply With Quote
Old 12-01-2010, 11:09 AM #142
sltvm2007's Avatar
Class 1 Laser
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
sltvm2007 sltvm2007 is offline
Class 1 Laser
sltvm2007's Avatar
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
Default Re: Homemade Scanning Laser Color Projector/TV

New scanner finished.
Attached Thumbnails
Homemade Scanning Laser Color Projector/TV-kuntman-s-scanner2.jpg   Homemade Scanning Laser Color Projector/TV-kuntman-s-scanner3.jpg   Homemade Scanning Laser Color Projector/TV-kuntman-s-scanner1.jpg  
sltvm2007 is offline   Reply With Quote
Old 12-08-2010, 09:14 PM #143
sltvm2007's Avatar
Class 1 Laser
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
sltvm2007 sltvm2007 is offline
Class 1 Laser
sltvm2007's Avatar
 
Join Date: Apr 2009
Posts: 63
Rep Power: 9
sltvm2007 is on a distinguished road
Send a message via ICQ to sltvm2007
Default Re: Homemade Scanning Laser Color Projector/TV

Block Diagram for the Electronic Circuit

Electonic circuit consists of the following parts:

Synch. separator
Divide by 2 circuits
Delay lines
RGB separator
Video amplifiers
Flyback blanking
Laser drivers
Filters
Vertical mirror driver
Horizontal mirror driver
Attached Thumbnails
Homemade Scanning Laser Color Projector/TV-block-diagram.jpg  

Last edited by sltvm2007; 12-08-2010 at 09:27 PM.
sltvm2007 is offline   Reply With Quote
Old 12-20-2010, 04:35 AM #144
zmr zmr is offline
Junior Member
 
Join Date: Dec 2010
Posts: 3
Rep Power: 0
zmr is on a distinguished road
zmr zmr is offline
Junior Member
 
Join Date: Dec 2010
Posts: 3
Rep Power: 0
zmr is on a distinguished road
Default Re: Homemade Scanning Laser Color Projector/TV

Hi, SLTVM,

What do you mean by blanking? Blanking what?
zmr is offline   Reply With Quote
Reply

Tags
camera, laser, lidar, projector, scan





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


LinkBacks (?)
LinkBack to this Thread: http://laserpointerforums.com/f47/homemade-scanning-laser-color-projector-tv-32628.html
Posted By For Type Date
Homemade Laser Projector - ImageStack This thread Refback 10-04-2015 11:11 PM
UV with an Xbox sled - Build Your Own SLA/SLS This thread Refback 06-24-2015 05:32 AM
teknolojik-forum.com Site Overview This thread Refback 05-19-2015 03:57 AM
Homemade Scanning Laser Color Projector/TV - Laser Pointer Forums - Discuss Laser Pointers This thread Refback 05-11-2015 09:38 AM
Build Your Own SLA/SLS ? View topic - UV with an Xbox sled This thread Refback 11-29-2014 09:44 PM
Build Your Own SLA ? View topic - UV with an Xbox sled This thread Refback 02-10-2014 07:07 AM
Laser Sintering Patent to Expire? This thread Refback 08-31-2013 06:31 AM
Cyclops - A Sideways step on DIY SLA idea This thread Refback 08-25-2013 09:32 AM
diy_3d_printing_and_fabrication : Messages : 4238-4299 of 7802 This thread Refback 01-04-2013 09:41 PM
???????? ?????????. - ?????? ?? DIYProjector.info - ???????? 25 This thread Refback 08-14-2012 01:22 AM
diy_3d_printing_and_fabrication : Messages : 4238-4299 of 5686 This thread Refback 04-26-2012 08:12 AM
Homemade Laser Projector - Page 2 This thread Refback 01-20-2012 08:59 AM
diy_3d_printing_and_fabrication : Messages : 4238-4284 of 4288 This thread Refback 01-07-2012 10:50 AM
SVETELEKTRO • Laser projector This thread Refback 09-30-2011 07:58 PM
Scannig Laser Projector - Science Forums This thread Refback 06-22-2011 08:27 AM
Homemade Scanning Laser Color Projector/TV This thread Refback 06-10-2011 08:55 AM
Son Mesajlar This thread Refback 06-08-2011 08:34 PM
Teknolojik Forum: Ev Yapm Taramal Renkli Lazer Projektr/ TV This thread Refback 06-08-2011 05:02 AM
Ev Yap?m? Taramal? Renkli Lazer Projektör/ TV This thread Refback 06-07-2011 06:17 PM
scanning laser projector/tv This thread Refback 05-24-2011 10:14 PM
Frum - Zobrazi tmu - Laser projector - Svet Elektroniky This thread Refback 05-22-2011 08:02 AM
laser projection tvs - results 3-b-s This thread Refback 05-15-2011 08:17 PM
Hacked Gadgets :: View topic - High Speed Analog Modulation of Green Lasers This thread Refback 04-26-2011 03:02 PM
Kuntman's Laser Projector on Vimeo This thread Refback 04-16-2011 07:24 AM
Homemade Projector TV / Computer - Cheap Bulbs - w/ Adapter ( Windsor Region ) $150.00 Classified Ad - Windsor, Ontario Movies For Sale | Inetgiant Windsor, Ontario Free Advertising Website This thread Refback 03-28-2011 01:35 AM
ma kuntman (sltvm2007) on Twitter This thread Refback 03-10-2011 02:35 AM
High Speed Analog Modulation of Green Lasers This thread Refback 02-25-2011 09:05 AM
Untitled document This thread Refback 02-24-2011 07:58 PM
Hacked Gadgets :: View topic - Homemade Scanning Laser Color Projector/TV This thread Refback 02-20-2011 03:45 PM
Der Weg zum Diy Laser-Beamer .. This thread Refback 02-10-2011 09:45 AM
Homemade Laser Projector This thread Refback 02-09-2011 10:36 AM










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 01:00 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