Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers



Laser Pointer Store

Greetings from Florida

jerry

New member
Joined
Nov 24, 2008
Messages
16
Likes
0
Points
0
Hello Laser Pointer Forums community!  I recently joined because of all of the excellent content I saw while browsing here, and because of my sudden interest in lasers :D.  I would also like to say props for having such an organized, helpful, and straightforward community ;D

My Laser Background:
I am now declaring lasers a new hobby of mine ;).  When I was a kid I had a little red key chain laser when they were still expensive and becoming popular.  I thought it was the coolest thing ever, but wished it did more than shine light really far.  I eventually heard about these green laser pointers that are so bright that you could see the beam, which made me really want one.  Back then they were hundreds of dollars and I couldn't really afford them.  Over the years I occasionally heard a thing or two about lasers.  At some point I saw videos of people popping balloons and lighting matches with lasers, but I still didn't get back into them.

Now, years later, green lasers are much cheaper.  Thanks to some friends of mine playing with cheap red lasers, I decided to buy one.  The other day I bought a green laser pointer from Amazon.com for $20.  It's 20mW and goes pretty far.  It feels cheap though because the button wiggles a lot and the brightness is inconsistent (probably because of the button).  I started doing lots of laser research after I bought mine.  Remembering some laser experiments on instructables.com, I went there and saw Kipkay's videos.  He made it seem very easy to make a powerful laser (for cheap).  Don't worry, I know now that his tutorials oversimplify the process (not to mention the skipped steps); his videos simply encouraged me to look into building my own laser for cheap.  I eventually found this forum, which has a wealth of information for the laser noob.  I read the FAQ, some intro threads, and basically familiarized myself with the aspects of building a DIY laser.  


Here's what I've gathered, plus questions (please correct me if something is wrong):
- A DIY laser generally consists of a host (like a flashlight) which has a housing, a driver circuit, and batteries inside.
- The housing has the laser diode and the lens, which is used to focus the light coming from the diode
  - The 2 main housings used are the Aixiz and Meredith.  Each can have an acrylic lens or a glass lens.  Acrylic lenses produce a tighter beam, while a glass lens produces a stronger beam.  The
    Meredith modules are of higher quality than the Aixiz.
  - Can both Aixiz and Meredith modules be focused with a knob on the front?  It looks like only the Meredith can (based on pictures I've seen).
- The driver circuit regulates the voltage and current flowing into the diode from the batteries.  This prevents the diode from burning up, and keeps the laser output the same as the battery life drains.
  - How do you make the driver small enough to fit in a flashlight?  I saw a picture of one on jayrob's site but the driver guide by Daedal doesn't show it all compact like that.
- Some colors like green, blue (i mean real blue 473nm), orange, yellow, and others use DPSS lasers instead of diodes.  These lasers use infrared diodes with crystals that modify the wavelength.  They
    need IR filters to filter out the excess IR leaking.  Where can I buy these DPSS lasers?  I want to make a blue laser at some point (if it's a realistic goal, I don't really know) but I haven't found
    anywhere to buy them.  I have a feeling they're expensive.

- What purpose does Amperage serve?  I see a lot of talk of mA, and I don't know what significance its value has on the laser's power.
- Is there any place to get cool laser warning stickers?  I think it would be cool to put one on a DIY.
- Are there any good ways to incorporate a locking mechanism (like a safety)?
- Sorry if this is a dumb question:  Does an ultraviolet beam (or close to UV like 405nm) have adverse effects on the skin like the sun's rays?  I don't want to inadvertently give anyone skin cancer or something.
- Do laser diodes heat up when in use? If so, how can I prolong its life and keep it from overheating?

I look forward to the lasers I'm planning on building, and to being a part of this community.
 

Elektrotechniker

Well-known member
Joined
Nov 10, 2008
Messages
4,254
Likes
176
Points
63
Hey Jerry. Welcome to the community  :) Glad to hear that one more person joined the forums. Personally, I wish you good luck with your experience here and I think you will succeed in building your own laser because, you seem to have a lot of fun with laser poiners :)
 

kristopher

New member
Joined
Oct 25, 2008
Messages
128
Likes
1
Points
0
jerry said:
  - Can both Aixiz and Meredith modules be focused with a knob on the front?  It looks like only the Meredith can (based on pictures I've seen).
Both have adjustable focus.

  - How do you make the driver small enough to fit in a flashlight?  I saw a picture of one on jayrob's site but the driver guide by Daedal doesn't show it all compact like that.
Surface mount components.  These are really small, so you can fit the whole circuit on a board the size of a quarter (or dime!)

- Some colors like green, blue (i mean real blue 473nm), orange, yellow, and others use DPSS lasers instead of diodes.  ... Where can I buy these DPSS lasers?
Check the buy/sell section - there are several for sale now.  There are also several companies that sell them (see laserglow for one).  The stickies in the buy/sell forum will help you see which companies are good.
 I want to make a blue laser at some point (if it's a realistic goal, I don't really know) but I haven't found anywhere to buy them.  I have a feeling they're expensive.
Yes, most components can be found on Ebay.  There are several forum members getting ready to build a green (least complex DPSS).  I'd try that first before you try a blue (more expensive, extremely difficult!)

- What purpose does Amperage serve?  I see a lot of talk of mA, and I don't know what significance its value has on the laser's power.
Most laser diodes operate in current mode where the current is fixed (not the voltage).  Think of the drivers as current sources, not voltage sources.  So, current most often relates to a power output (at a particular temperature, etc).  Often you will see power vs current graphs.  More current, more power until the diode dies!

- Is there any place to get cool laser warning stickers?  I think it would be cool to put one on a DIY.
Check the buy/sell.  There are a couple of forum members that sell them.

- Are there any good ways to incorporate a locking mechanism (like a safety)?
You can have two switches.  One is a key and the other a button.  Then the key has to be on AND the button pushed.  There are other ways as well.

- Does an ultraviolet beam (or close to UV like 405nm) have adverse effects on the skin like the sun's rays?  I don't want to inadvertently give anyone skin cancer or something.
UV, Vis, and IR can all cause skin problems.  Remember, mW is mW!  You ever heard the joke about which weighs more, a ton or stones or a ton of feathers?  Yeah, they are both the same. true UV and IR are dangerous (IMO) because you cannot see them.  Be careful!

- Do laser diodes heat up when in use?  If so, how can I prolong its life and keep it from overheating?
All diodes heat up some when laseing.  If you want a diode to last a long time, don't run it at the "max" mA value, but a more conservative (60%?) and also use heat sinks.  Phowa hungry forum members will recommend running at max power, but only for 10 seconds at a time or something like that.

Hope I covered your questions.

Welcome!
 
Joined
Mar 25, 2008
Messages
215
Likes
2
Points
0
Err... I don't know if that was intentional or not, but five posts in a row saying the same thing is spamming...
 

daguin

New member
Joined
Mar 29, 2008
Messages
16,636
Likes
624
Points
0




Top