My Blu-ray wont focus!

[lazer]

I recentaly finished building my 100mw blu-ray running on a ddl driver set to 110ma. I was able to focus it and burn stuff. I am using an acrylic lens. But Today when I tried to light a match I tried to focus it and as the dot got smaller it turned into a rectangle. Once it was a rectangle I could not get the laser to focus to a smaller pinpoint size dot for burning. The dot now stays about 2 mm big and won't burn. :'(

How do I get it to focus right it was working fine the day before? :-/

 

[daguin]

I recentaly finished building my 100mw blu-ray running on a ddl driver set to 110ma.  I was able to focus it and burn stuff.  I am using an acrylic lens. But Today when I tried to light a match I tried to focus it and as the dot got smaller it turned into a rectangle.  Once it was a rectangle I could not get the laser to focus to a smaller pinpoint size dot for burning.  The dot now stays about 2 mm big and won't burn. :'(  

How do I get it to focus right it was working fine the day before? :-/

Sounds like something "moved." Have you unscrewed the lens to see if something is loose or if the spring is caught up on something?

Peace,
dave

 

[lazer]

Yes this would make sense since I had removed the lens then replaced it before turning it on........I did check to make sure the spring was not in the way after it quit focusing right.

 

[daguin]

Yes this would make sense since I had removed the lens then replaced it before turning it on........I did check to make sure the spring was not in the way after it quit focusing right.

Is the back of the lens "opened" up?

Peace,
dave

 

[lazer]

No it is the before picture. The small hole is facing the laser diode.

 

[daguin]

No it is the before picture.  The small hole is facing the laser diode.

Open up the back. There may be something inside the lens nut.

Also, while you have the lens out, shine the light on a wall, close enough to be able to see the unfocused "circle" of light and slowly spin the laser while it is still pointing at the wall. Does the light "change"? If not, try GENTLY tapping the laser to see if the light changes. What we're trying to ascertain is if the window is broken or loose.

Peace,
dave

 

[Elyk456]

I recentaly finished building my 100mw blu-ray running on a ddl driver set to 110ma.  I was able to focus it and burn stuff.  I am using an acrylic lens. But Today when I tried to light a match I tried to focus it and as the dot got smaller it[highlight] turned into a rectangle[/highlight].  Once it was a rectangle I could not get the laser to focus to a smaller pinpoint size dot for burning.  The dot now stays about 2 mm big and won't burn. :'(  

How do I get it to focus right it was working fine the day before? :-/

I am using an Aixiz module, Im not sure if you are, but I have noticed a rectangle on mine, but thats after I burnt out the diode, its only and Led now...but I do notice a rectangle.

 

[sevaspeto]

So I was hooking up a phr803 in an Aixiz to a lab power supply the other day and noticed that at any current < 10ma makes a rectangle and wont focus it. Also part of the rectangle also appears to be white. but as soon as it gets above 10ma or so it changes to a dot. not sure if that helps but it might be of interest, it could also be a mode shift of some sort.

 

[jnrpop]

[quote author=lazer link=1231650851/0#2 date=1231651395]Yes this would make sense since I had removed the lens then replaced it before turning it on........I did check to make sure the spring was not in the way after it quit focusing right.

Is the back of the lens "opened" up?

Peace,
dave[/quote]

Hi , is it best to open up the back of the acrylic lense or doesnt it really matter???
Ive opened up one but couldnt really c see a difference in the beam at night.
That was with dodgi batteries though!

 

[lazer]

The light dose not change.

I am using an axiz module with acrylic.  

The laser is only set to 110ma. How could it have burnt out. I found a thrad a while ago where Daguin said that at 110ma violet diodes should last a long time.

 

[CRFultz]

There are so many variables that can effect the lifespan of a diode. There are no guaranties. Are you sure it's dead? Have you checked voltage? Did a solder connection come loose? For it to work then not could stem from incorrect amperage or maybe something loose, or maybe battery voltage/ connection.

If you have the means, check the draw and see what it's consuming. Maybe the drop across the diode would help diagnose the problem.

 

[daguin]

The light dose not change.
I am using an axiz module with acrylic.  
The laser is only set to 110ma.  How could it have burnt out.  I found a thrad a while ago where Daguin said that at 110ma violet diodes should last a long time.

Does it "look" bright if you shine it on a white piece of paper or a white shirt?  Without a Laser Power Meter, it is VERY difficult to estimate the output of a laser.  You only reported the change in "shape" and that it wouldn't burn.  Has the output changed significantly?  Does it "appear" to you to be MUCH dimmer?

There are MANY things that could make the diode "burn out" before "its time."

If it was overheated during soldering
OR if it was subjected to an ESD
OR if it was subjected to a significant impact
OR if it was overheated while removing the PCB and ribbon cable
OR if one of the pins got twisted or pushed in slightly
OR if there was an intermittent disconnection of the diode
OR if it shorted out somewhere
OR several other potential problems

Hi , is it best to open up the back of the acrylic lense or doesnt it really matter???
Ive opened up one but couldnt really c see a difference in the beam at night.
That was with dodgi batteries though!

You cannot "see" the difference.  It CAN be measured with a Laser Power Meter however.


Peace,
dave

 

[lazer]

So it probably burnt out  :'( but I can still see the beam at night  I will check the connections and voltage ect.  How do I check draw? The voltage across the diode is 4.24 volts

 

[daguin]

So it probably burnt out  :'( but I can still see the beam at night  I will check the connections and voltage ect.  How do I check draw? The voltage across the diode is 4.24 volts

If you can still "see" the beam, you are VERY sensitive to 405nm light, or the diode is a longer wavelength, or there is alott of "stuff" in the air where you are, or it is not blown.

If you are only getting 4.2V across the diode it is NOT getting enough voltage. Give it at least 5V and see what happens. What is the battery/driver combination you are using? Have you checked ALL of the electrical connections? Clean anywhere that an electrical connection exists in the unit (threads, springs, battery, etc.) Also check for any shorts. Finally re-check your solder joints.

Peace,
dave

 

[lazer]

Im using alkiline ddl driver combo.  I just resoldered everything and checked the connections.  I can't get the ddl driver to give 5v its only giving 4.23. :-/  I think the diode is definetly dead though because it was working fine two days ago. :'(

I want to build a new blu-ray laser ;D what current should I run it at? This laser died at 110ma :'( What current should I run my new laser at. I plan to get the diode from the person who sells them for $12. whats there user name? I think I will try a flexdrive with the new laser im going to build

 

[Elyk456]

Im using alkiline ddl driver combo.  I just resoldered everything and checked the connections.  I can't get the ddl driver to give 5v its only giving 4.23. :-/  I think the diode is definetly dead though because it was working fine two days ago. :'(

I had the exact same thing happen to me when I was running my Phr at 120mA. I used it for probably 5-10 minutes of ON time, over the 48 hours. From what I understand, PHRs are all very different, some withstand 150-200mA and some die at 110. Your taking a chance of the diode dieing pretty much anywhere over 100mA. Again, thats just from different things I have read, I COULD be wrong.

I want to build a new blu-ray laser ;D  what current should I run it at?  This laser died at 110ma :'(  What current should I run my new laser at.  I plan to get the diode from the person who sells them for $12.  whats there user name?  I think I will try a flexdrive with the new laser im going to build

I used a flexdrive on mine at 120mA and it died out. I plan on running my new one at 100mA, which I feel will be alot safer, but again, it still even has a chance of burning out at 100mA. There are alot of users in buy sell and trade that sell Phr cheap. Some that I see off the bat are, $10 here: http://www.laserpointerforums.com/forums/YaBB.pl?num=1231587816 and $13.50 here: http://www.laserpointerforums.com/forums/YaBB.pl?num=1228038791



If you want to get a flexdrive, you can buy them directly from Andrew here : http://hacylon.case.edu/ebay/laser_diode/Micro_FlexDrive.php


I don't know if you want to use the same host / heatsink, but if you want to start completely over, you can do a dorcy build and get a darkhorse heatsink. A very good guide written by Hvnsent can be found here: http://www.i-hacked.com/content/view/272/94/