Chad said:
We don't want to dumb it down too much... not everyone who's new to lasers is new to electronics.
Styro - I put both of those in there because I wanted to cover all the bases... I noticed a few things that you didn't mention in your topic. I knew about Ohm's law, that's why I put the thing about voltage spikes in there. And I really don't see why BL shouldn't be on the good companies list, because there sure aren't any BAD reviews about them, and we all trust Blue and Spyro.
Just food for thought.
I'm not saying BL shouldn't be on the good companies list, I'm saying it shouldn't be on the great companies review list just yet. There are no bad reviews on lasergreen.com or greenlaserbeam.com either
You're right about saying that not all new people to the lasers are also new to electronics. I know I was, but there are a lot of people that have a lot of electronic experience behind them so I think we should leave the thing about voltage spikes in there.
Okay, here is the latest FAQ! This page will become huge with future edits. Should I post this in the General section now? We can always edit it from there.
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Title: Basic FAQ - Read before posting!
Here is a list of frequently asked questions made by newer members of these forums. Please, before asking questions, read this list, and search the forum before posting. There is a 99% chance your question has already been answered before, so search around before asking questions.
Getting Started
What is a laser?
"Laser" is an acronym that stands for "Light Amplified by the Stimulated Emission of Radiation" For the technical stuff regarding lasers, read
Sam's Laser FAQ for a good idea of what lasers are and how they work. Don't worry, you don't need to know all of the technical info to get started in the laser hobby.
What do "mW" and "nm" mean?
mW stands for milliwatt, a measure of energy. nm stands for nanometer, a measure of length. In lasers, mW is used as a unit to describe the power of lasers. Basically the higher the power, the brighter the dot and beam will be. Also, with more power comes more burning capability. nm refers to the wavelength of the laser. Wavelength can basically be thought of as a very specific color. Common wavelengths you will see here are 405nm (violet), 473nm (blue), 532nm (green), 593.5nm (orange/yellow), and 650-670nm (red).
This is a good illustration of the visible spectrum.
What else can I do with a laser besides burning stuff?
Here are some great examples of other cool tricks you can do with lasers besides just burning stuff:
Spirograph
Scanner
Liquid Sky
Time Tunnel
And this is just the beginning of what lasers can do!
Your First Lasers
I want to buy my first laser, what one should I get?
This is a difficult question. It depends on YOUR wants and needs, and chances are that we don't have a clue what those are. Basically, there are three well-known companies that are extremely reliable, and will never disappoint: Nova Lasers (
www.novalasers.com ), Optotronics (
www.optotronics.com ), and Laserglow (
www.laserglow.com ). Between those three, you should be able to find what you need for a relatively low price.
Keep in mind, though, that there are many more companies that can't be trusted to give you anywhere near what you pay for. The most common company is Wicked Lasers/TechLasers. They are infamous for selling overpriced, underspec lasers. They market to people who have no experience with lasers, and that tactic is what's kept them alive for so long.
In addition, read over
this topic. Many other questions are answered there.
Okay, I just got a laser, what batteries should I use?
For pen style units that take AAAs, alkaline batteries are at the bottom of the best batteries list. The voltage of them sags after little use, and they die quickly in a high power consuming unit like a laser. Rechargeable batteries usually work the best, Eneloop AAAs by Sanyo are arguably the best ones. For maximum performance from your laser, you also can buy expensive lithium AAA batteries, but after buying these for a while you will realize they do take a good chunk out of your laser budget!
For lithium batteries, especially rechargeables, make sure you only buy batteries from respected brands. Cheap knock-offs have been known to explode either in the charger or in the device that is using them, so invest a few extra dollars in good batteries when you buy them.
DealExtreme?
For a first laser, DealExtreme (DX for short) is a nice choice. They offer a lot of lasers with different outputs, the 5mW is known to be good for presentations, nice and stable. If you just want to see a bright beam at night, you should go with the 30mW one. The lasers at DX are not the best quality, but their great prices make up for this. There are some bad lasers sold at DX though, read around the forum to see which ones they sell are good and which ones are bad.
But what's the deal with the "True" ones?
The "True" green laser pointers from DX are the ones which have a
NewWish brand diode, which are known to be more reliable than the generic ones used on the non-true laser pointers. If you want to be safe, go with the True Green 30mW. And contrary to popular belief, the "true" series of their green lasers 50mW and under DO have IR filters.
What about Kaidomain?
KD for short, it is a lot like DX, the 50mW CR2 green laser that they offer is known to be a good buy. Their 30mW option is said to be the same as the True 30mW from DX (although the first is cheaper).
DIY Laser Questions
DIY Lasers are a common interest around here, and there are many things you need to know before endeavoring to build one.
How do I build a burning red laser?
You need to buy a laser diode and build a driver to power your diode. A great driver you can make at home is found
here.
Once you buy a diode and make a driver,
this is a very good tutorial for slapping it all together.
I'm new to electronics, and I don't know how to make a driver. Help!
A member here made a great video walk through on making a driver.
Check it out.
Where do I buy burning red laser diodes?
For burning red laser diodes,
this is your best bet to start off with. Buy a couple of them, as you will find yourself making mistakes that could kill your first diode. It's always good to have backups. You can also buy a bunch of other parts you need to build laser with at that site, including DIY laser diode Driver kits, modules to heatsink and focus your laser diodes, and more.
You can also buy DVD burners, and salvage the diode from them. This option, although more expensive, is a good way to get more powerful diodes than the ones offered in the store above.
I saw KipKay's laser flashlight hack, can I have some help?
DO NOT follow KipKay's laser flashlight hack. In that video, KipKay hooks the laser diode directly up to the batteries with no current regulation at all. One of the biggest "no-nos" in the DIY laser hobby is too hook a laser diode directly up to batteries. This is why KipKay's laser hack doesn't work: there is a difference between light bulbs and Laser Diodes. Light bulbs are controlled by the the voltage, that's why the bulb itself is working so well directly on the batteries. Laser diodes, however, aswell as other semiconductors, are controlled by the current. So, if you try to feed a LD directly on to the batteries, there is nothing that controls that current. Let's say that the LD need 3.0v, 200mA to operate and you hook it up to the batteries (3.0v), will it work? Yes it will, but with even the slightest change in temperature will make the LD require less voltage and a HUGE amount of current will flow through it, and kill it.
Here's an example: LD = 2.9v, batteries = 3.0v = dead LD.
I need a driver but I don't want to build my own. Where can I buy some?
The
AMC7135 may be a good choice for you. It's small, cheap, and easy to use. Also, sometimes there are group buys for small drivers, so check out the Group Buys section for good drivers.
Safety Questions
Do I really need eye protection?
Yes, technically for anything over 5mW you need goggles for. Goggles usually run around $50 a pair, but you have to realize that your eyes are worth more than whatever you pay for goggles. One unlucky hit in the eye with almost any laser and you will have a permanent blind spot. A saying you will hear around here is "You can only look into a high powered laser twice, once with each eye". This is because it only takes a tiny fraction of a second to blind yourself or severely damage your eyes.
Can I use sunglasses or Welding Goggles for at least some laser protection?
No. This is a common misconception. All sunglasses/welding masks will do is make your pupils dilate, which makes the potential for damage much greater. Need a demonstration?
Watch this short clip.
Browsing the Forum
All of the abbreviations and terms are confusing me, what do they mean?
LD = Laser Diode
DDL's Circuit = Daedal's Circuit, a great laser diode driver that Daedal, a member here, developed.
WL = Wicked Lasers, one of the first companies to sell high powered lasers in pen size. Does not have a good reputation around here because they are known to send out underspec units.
LG = LaserGlow, a company that sells a wide variety of lasers.
TL = Techlasers, a branch of Wicked Lasers.
SenKat Diode, or SenDiode = A laser diode equivalent to the red laser diode found in 16x DVD burners.
DX = DealExtreme, a company based in China that sells many, many gadgets at cheap prices. They sell mediocre green lasers at great prices.
KD = Kaidomain, a company that sells a wide variety of products, including cheap green lasers.
Dilda-Lazor = A 200mW red pen-sized laser sold by the company DealExtreme. This name was given to this laser by spyrorocks because it resembles, well, you know. :
LC = Laser Community, Forum operated by Wicked Lasers. Most people here don't enjoy LC because they ban you if you say anything bad about WL or if you mention another laser company.
CNI = A manufacturer of a bunch the lasers we use. Most of the time this is used as "CNI pen" Which is a high powered green laser in a pen style. An example of a CNI pen is Nova Laser's X-Series.
This FAQ was written by styropyro, Chad, nikokapo, and FireMyLaser.
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