Hello all, Alex here. I remember seeing in a thread a few days back a thread on what are some of the Pros & Cons about "Common" Wavelengths.
I haven't seen any post on this so I decided to take a crack at this, hope you enjoy :beer:
405nm
Picture:
100mW-405nm-Violet-Purple-Blue-Laser-Module-Focused-Dot-M405D10031670_1 | Flickr - Photo Sharing!
Pro's
- Is a stable wavelength, which means you do not have to worry about temperature affecting performance as much as
532nm
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Laser diodes are stable. 405nm as a wavelength is not "stable." Because the emission comes directly from a laser diode, the output tends to be stable despite temperature changes.
- Only wavelength which somewhat "Changes Color", if 405nm is aimed on white surfaces it turns
blue.
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It's called fluorescence. If you're going to write a "guide" you NEED to know that.
- Can be used to write on Glow-in-the-dark materials
-
GITD materials are "charged" by UV. Because 405nm photons are near UV, they have enough photon energy to work.
Con's
- This wavelength being at the end of the spectrum will not appear BRIGHT AT ALL
-
Brightness also has dependence on power. Holding power constant, 405nm will be much less visible than wavelengths closer to the center of the visible spectrum.
- Cannot be had in huge amounts of powers, MAX 2W.
-
Yes it can. It's just very expensive. That is a very important distinction.
445nm
Picture:445nm | Flickr - Photo Sharing!
Pro's:
- Can be had at incredible amounts of power for cheap
-
This depends on someone's concept of "incredible." Perhaps mentioning that up to over 3W can be had for just a few hundred dollars would work better.
- Is the best wavelength for burning/lighting combustible materials
-
405nm is the best commonly available wavelength to burn with, holding power constant. This is due to the photon energy inherent to shorter wavelengths. Similarly, 355nm would "burn" better than 405nm, holding power constant. Additionally, materials don't have to be strictly "combustible" to be marked by lasers.
- Have beautiful beams
-
That's kind of subjective, isn't it?
Con's:
- (Even thought not noticeable) have an ugly rectangular aperture beam
532nm
Picture:1mW-532nm-Green-Laser-Module-Single-DotM532D131660_1 | Flickr - Photo Sharing!
Pro's:
- Brightest wavelength out of them all
-
Brightest wavelength than others in this guide (holding power constant), yes. But not of the whole spectrum.
- Easiest wavelength to observe a beam at
-
That may not be true depending on the power. This is another "holding power constant" statement that can be misleading.
- Has a nice, clear circular dot
-
That depends on the quality of the laser. Cheap Chinese pointers often have messy dots that change shape as different transverse modes come and go. By saying this, you might lead a newcomer to buy a laser that will disappoint them, because the dot does not live up to "circular."
Con's
- Can be highly unstable, temperature will easily affect power output
-
If not thermally stabilized, yes.
- Can easily be damaged
-
Due to the fragility of the alignment. Might want to mention that.
- Price rapidly climbs as output of unit increases $$$$
-
It starts climbing earlier. Every wavelength has a power at which the price starts to skyrocket.
650nm
Picture:red-laser-module-5mw-focusable-650nm-dot-798974-Gallay | Flickr - Photo Sharing!
Pro's:
- Most readily available wavelength for purchase(can be found everywhere)
-
Indeed!
- Can be had at high powers for cheap
-
This depends entirely on your concept of high power. This needs clarification.
- Highly stable
-
Laser diodes are stable. 650nm is not inherently stable. There are DPSS options for 650nm that invalidate this statement.
Con's:
- Worst wavelength for burning/lighting(Some materials)
-
Of this list, perhaps. It is not the "worst" of all wavelengths...
Thank you for reading, this is just a quick, fast easy thread for new users who may be deciding on which wavelength is best for them.
Like always, it all depends on what you will be using you're laser for, different wavelengths will excel in different domains.
Like always, if you feel this need any re-adjustments, please do not hesitate to write a post below and I will get to it as quickly as possible :beer:
