638 vs 650nm visual doubth

[laserdelic]

Im preparing a .5~1W RGV system, and Im douthing between using 638nm @300mw or 650x2 @250mw.

As stated here, the visual power should be approx the same, only varing the hue in the output. Is that orangish really almost double visually potent than 650 reds?

 

[Cyparagon]

Yes, 638 is exceptionally brighter. By the way, DVD diodes aren't 650, they're at least 660nm and usually higher. I've measured some at 666nm.

638 is not orange, ~610 is orange. Most red LEDs peak somewhere between 620 and 635.

 

[laserdelic]

Excelent. Thank you Cyparagon.

For the 635nm@300mw Im thinking in one brand new mitsubishi. For the 650 option was thinking in lpc-825´s, but I think I´ll go for the mitsu, even more if you tell me it goes 660nm and beyond.

 

[justinjja]

Seen this?

This is from an LPC-826

 

[jeffreythe00]

Which 635's do you plan on using? Multimode or single mode?

 

[laserdelic]

Nice charts, Justin, very informative. Definititely 638nm, probably the mitsu@300mw that costs around 50$

Didn´t even know exist multi and single mode. Are we talking about 2 "filaments" encapsulated in 1 can?. Pros and cons?. The inexpensive is a plus in this building.

Thank you guys.

 

[midias]

Nice charts, Justin, very informative. Definititely 638nm, probably the mitsu@300mw that costs around 50$

Didn´t even know exist multi and single mode. Are we talking about 2 "filaments" encapsulated in 1 can?. Pros and cons?. The inexpensive is a plus in this building.

Thank you guys.

The mitsu diode is multimode and has really bad divergence.

 

[jeffreythe00]

The advantage of using 650 diodes over a 300mw mitsu is. The 300mw Mitsubishi diodes are multi mode and the beam spreads out over a large distance which is not ideal if you plan on doing animated shows.

If you are just doing beam shows. 635 is fine as you won't notice the red much.

 

[laserdelic]

Is intended for building a RGV proyector, so divergence could be a problem. I was so close to buy it... The divergence issue comes from the dual mode technologie in general or from the mitsu oranges in particular?.

Are there another red (638?) ones with a good price/visibility relationship?. I know these are a lot of questions

 

[DTR]

The 300mW are most commonly used in projectors but with correction optics to tame the output. There is a lot of info in this thread and common setups.
Mitsubishi ML520G71...Red Holy Grail or Flashlight Fail ??

Alternatively both Mitsu and Opnext have single mode 635's but they are a little lower power in the 100-180mW range. The more economical 110mW Mitsubishi's I stock.