ECDLs tune by fiddling with the operating temperature and they adjust within a range of like +/- 3nm, or something like that. Someday, tunable diode across the entire spectrum may be readily available.
At best you can get a tuneable ArKr laser which will have lines in blue, green, yellow, and red, but I think to get all the lines you need a double brewster tube with interchangeable HR and OC pairs.
Are Krypton Ion lasers tunable to ANY wavelength, or only those wavelengths it's capable of lasing at? I did not think these lasers were infinitely tunable, only tunable (more like selectable) to the lines available.
Conversely, ECDLs are be infinitely tunable within their (narrow) range of operation.
I welcome any feedback to help me get this right in me wee little head.
Sorry did not mean to imply they are tunable to any wavelength. They just have many, many lines through the visible spectrum, from UV through NIR. I think the highest gain ones have several lines in deep blue, central green, upper yellow, and red.
So, then how do you "tune" them to the different wavelengths. I'm probably in over my head on this one, but how else are you gonna learn? I'm assuming you have to turn off the power to go to the other wavelength.
We're still referencing an ArKr Ion laser here right? It normally produces all of the lines simultaneously. You either let them all out at once or you filter out the ones you don't want. One with an intravacity prism would have a prism inside the cavity which moves the line you want into alignment with the HR mirror so it gets more than single pass gain. This is normall called a Tunable ArKr laser as you tune the cavity to provide gain to the desired wavelength line. They are harder to produce than a standard multiline ArKr though. You don't turn them off to tune, there just isn't enough gain to get any real lasing when the prism is out of alignment, so you get no beam.
Ok. Can you tell me what an HR mirror is and is it similar to the mirror/ lens in a dvd player? Also, do you have a picture of diagram of what we are discussing?
Thanks
While I appreciate your thirst for knowledge and willingness to learn, we're reaching the point where it would take a large amount of effort (and time) on my part to explain the concepts and physics behind the operation of lasers. The short answer is no, it is not like any lens you have encountered before. Likewise, the ArKr laser is a gas laser about the size of a small counter top, not a portable device. Diode based lasers are only tunable over such a small range that the eye cannot tell the difference in color. Truly tunable lasers are very large systems.
Thanks for the reply. Sigh. Guess I'll have to get some books and read. Not that I'll ever get something that big, but it still is intresting to know. When I first stumbled upon this site it was just to do one build maybe 2, but know I am pre-planning several. And I'm also getting hooked on Flaminpyro's niche of pyrotechnics. Not enough time and money.
So what is the difference between a tunable laser system and a MEMS projector like the one below? i mean you are technically combing three RGB lasers, but hey its tunable....