445 vs 473

[Joshuan]

Hello everyone.

Sorry about the lame question, but what are the main differences between a 445nm and a 473nm? Also, which ones are used in projectors?

Thank you.

 

[Speedy78]

445 is blue and 473 is a sky blue. Tv projectors? 445nm

 

[Joshuan]

So true blue lasers are 445?

Where were 473 used?

 

[IsaacT]

True blue is closer to 473. 445 is very indigo in comparison. 473 might be used in spectroscopy or holography.

 

[ARG]

473nm was used in laser projectors before cheap 445nm came along as well.

 

[Kookapeli]

Um, 28 ???

 

[Things]

473nm looks a lot nicer than 445nm

 

[Joshuan]

445 on the left?

 

[hwang21]

Haha^ because 473nm is usually a DPSS process, it is costly, complex, and inefficient, so most projectors now use 445nm diodes. Before 445nm diodes, however, they were forced to use 473nm

EDIT: 473nm on the right

 

[Things]

Yep, looks almost violet when you put it next to 473nm.

 

[Trevor]

473nm looks a lot nicer than 445nm

...but 457nm (or 458nm if you prefer ArIon) is, IMO, the best blue out there.

Trevor

 

[nueces]

445 on the left?

Ummmm, I would say yes. %^)

 

[Joshuan]

Things, what power are those two you have?

 

[Things]

...but 457nm (or 458nm if you prefer ArIon) is, IMO, the best blue out there.

Trevor

Multiline argon is by far the best colour there is, but at least 473nm is practical

They were both around 20mW, the 445nm in my projector was turned down so it didn't wash out the image too much.

 

[EpicHam]

For a better comparison of colors .
I recommend once again.
THE ROHANHILL TOOL!!!
USE IT!
USE IT!
USE IT!!!!!

As for the 445nm to 473nm comparison.
445nm diodes are fabricated directly with InGaN semiconductors, which produce blue light without frequency-doubling. Giving you a royal blue laser.
473nm DPSS lasers is produced by frequency doubling of 946 nm laser radiation from a diode-pumped beta barium borate (BBO) or lithium triborate (LBO) crystal. Giving you a sky blue color.

Advantage and Disadvantages :
445nm diode lasers are a lot cheaper and more efficient.
445nm diode lasers are more drop resistant.
445nm lasers are commonly available and can be made using projector parts.

473nm DPSS are VERY expensive and the frequency doubling process results in efficiency in the low 5-6%
473 DPSS lasers cannot be dropped as shocks may misalign the crystals .
473nm lasers are rare and require fabrication by specialists.

 

[Things]

405nm lasers are from blu-ray players, 445nm is from projectors.