I have a couple of questions about violet lasers diodes. I don't want to start multiple threads, so I'm condensing them into one topic.
1. How common are multi-mode 405 nm diodes nowadays? I was under the impression that violet laser diodes are generally single-mode as that's what optical drives require, but I've seen a few multi-mode diodes elsewhere. For example, Thorlabs sells a 400 mW 404 nm diode that's multi-mode, and Laserglow's Electra Pro series are also multi-mode per the specs. Some of the reviews for high-powered violet lasers also mention a large beam diameter, which suggest they could be multi-mode as well.
2. Per above: if the more powerful 405 nm lasers still use single-mode diodes, then why do they have such large beam diameters? Aren't lasers with shorter wavelengths supposed to have better beam specs?
3. Are high-powered single-mode diodes made exclusively by Blu-Ray drive manufacturers, and if so, are they patented? I looked at some of the online catalogs, and the single-mode 405 nm diodes only go up to 150 mW or so.
1. How common are multi-mode 405 nm diodes nowadays? I was under the impression that violet laser diodes are generally single-mode as that's what optical drives require, but I've seen a few multi-mode diodes elsewhere. For example, Thorlabs sells a 400 mW 404 nm diode that's multi-mode, and Laserglow's Electra Pro series are also multi-mode per the specs. Some of the reviews for high-powered violet lasers also mention a large beam diameter, which suggest they could be multi-mode as well.
2. Per above: if the more powerful 405 nm lasers still use single-mode diodes, then why do they have such large beam diameters? Aren't lasers with shorter wavelengths supposed to have better beam specs?
3. Are high-powered single-mode diodes made exclusively by Blu-Ray drive manufacturers, and if so, are they patented? I looked at some of the online catalogs, and the single-mode 405 nm diodes only go up to 150 mW or so.
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