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



Are these just different names for the same type of laser?

Ben321

New member
Joined
Apr 7, 2021
Messages
17
Points
3
I've seen some blue laser pointers that claim 445nm, others claim 447nm, while others 450nm. Are these all actually refering to the same technology of laser diode, but the sellers are being imprecise and just rounding the numbers differently? 447 rounded to the nearest 5 would be 445, while 447 rounded to the nearest 10 would be 450. Are all of these laser pointers (regardless of what the company is advertizing them as) actually using a 447nm laser diode? Or are these actually 3 different wavelengths of laser diodes?
 



CurtisOliver

Well-known member
LPF Site Supporter
Joined
Jun 12, 2015
Messages
7,254
Points
113
Laser diodes are typically +/- 5nm. So a 445, will usually be in anywhere between 440 to 450nm. They are the same technology but won't necessarily be the same laser diode. When it comes to diodes, they can only be taken to 1nm resolution when spectrographed. Diode wavelength also naturally shifts with input current and operating temperature.
 

Encap

Well-known member
Joined
May 14, 2011
Messages
6,097
Points
113
Yes they are all direct diode lasers. No, wavelenghts are not just names the are wavelenghts.
Different wavelengths are not they result of resellers rounding off anything.
That is just a daydream/imagining of someone who doesn't know what they are talking about. lol

"Technology" is just a category/type of laser. Like Gasoline or Diesel Engines are different catagories of engine.
Example: Direct Diode or DPSS --different technology lasers

There are different diodes makers, different diodes, different wavelengths, different availability, different outputs, different prices .

If you want to see diodes are available for hobby pointer builders generally. See reliable resource and reseller of new unused diodes DTR here: https://sites.google.com/site/dtrslasershop/home/diodes
Look here at listing of over 10,000 different diodes, modules, and systems : https://www.laserdiodesource.com/
 
Last edited:

Ogskylr

New member
Joined
Apr 12, 2021
Messages
14
Points
3
I've seen some blue laser pointers that claim 445nm, others claim 447nm, while others 450nm. Are these all actually refering to the same technology of laser diode, but the sellers are being imprecise and just rounding the numbers differently? 447 rounded to the nearest 5 would be 445, while 447 rounded to the nearest 10 would be 450. Are all of these laser pointers (regardless of what the company is advertizing them as) actually using a 447nm laser diode? Or are these actually 3 different wavelengths of laser diodes?
They are all the same color to the human eye I believe, though there seems to be a slight variance, I have a advertised 445 and 450 and the 450 is a bit more royal blue than 445 UV.
 

Encap

Well-known member
Joined
May 14, 2011
Messages
6,097
Points
113
They are all the same color to the human eye I believe, though there seems to be a slight variance, I have a advertised 445 and 450 and the 450 is a bit more royal blue than 445 UV.
Except he didn't ask anything about "color"and you didn't address any aspect of his question.
Nobody cares what you did or did advertise or sell on eBay and to say "450 is more royal blue than 445 UV" is preposterous, nonsensical, and misleading.

In pretty clear English he asked 445nm 447nm and 450nm. Are they actually different wavelengths or just rounded off nm numbers and are there actually 3 different wavelengths and 3 laser diodes different from each other or are all of them the same 447nm just named differently?

Please don't troll post nonsense and misinformation for attention or whatever reasons when you don't know what you are talking about. It misleads and misinforms other guests and members who see and read LPF posts.
445nm is not a UV wavelength.
Ultraviolet radiation lies between visible light and X-rays. The UVR spectrum ranges from 10nm to 400nm and the commonly discussed portion "Ultraviolet" UV is between 100nm and 400nm divided into three bands: UVA (315-400 nm) UVB (280-315 nm) UVC (100-280 nm).

"The electromagnetic spectrum of ultraviolet radiation (UVR), defined most broadly as 10–400 nanometers, can be subdivided into a number of ranges recommended by the ISO Standard ISO-21348"
From: https://en.wikipedia.org/wiki/Ultraviolet
 
Last edited:




Top