The difference between 637nm&650nm Red

[Song]

Hi,
Bla bla bla bla.....

Pictures:



637nm Red is 1W, and 650nm is 1.3W.


PS: this is not SPAM -_-, just give you a visual for the 637nm and 650nm red.

[gottaluvlasers]

Song-

this is actually an EXCELLENT visual post!!! thank you. Its amazing HOW much brighter and "cleaner" the 637 is.

Thank You.

-Marc

[flecom]

man if I could only win the lotto

[142laser]

The difference is 13 nm by the new math... cameras don't tell the whole story either...the eye is not linear.

[lloyd33]

A camera may not interpret the light the same way as a human eye,
but I think this gives a pretty clear picture (no pun intended) of who
the obvious winner is.

[buffo]

Agreed. Even if you disregard the color difference, it is obvious which one has the better beam specs.

Adam

[laserist]

except that too can be an artifact of the camera lens...

Agreed. Even if you disregard the color difference, it is obvious which one has the better beam specs.

Adam

[Bradfo69]

I'm not certain, I understand why you're saying the 637 has better beam specs or, is "cleaner". Yes, it's definately a lot brighter, even with less power but, to me, and maybe I don't fully understand, the 650 appears to have a smoother look without all the orange fringe around it. The "width" of the 650 as compared to the width of the whitish center of the 637 is bigger, yes. I'll grant you that but, I guess my definition of clean leans toward the 650. Guess I need to be better edjukated.

[andy_con]

the 660 open can diodes are single mode with a small emitter, just the same as 637 diodes. therefore the beams specs are the same

its the brightness thats very different

[buffo]

the 660 open can diodes are single mode with a small emitter, just the same as 637 diodes. therefore the beams specs are the same

The picture doesn't show a 660 nm open can diode, Andy.

The title says "difference between 637 nm & 650 nm red". No one ever mentioned 660 nm...

I agree that 660 nm and 637 nm do have similar beam characteristics. But 650 nm diodes have *MUCH* larger emitters, which gives them that characteristic fat beam that is very evident in the picture. Also, the higher power 635 nm reds share this trait.

The apparent brightness is a separate issue.

And Brad: the "halo" you see around the 637 nm red is an artifact of the camera. It doesn't look like that in real life.

We have done side-by-side tests at previous LEM's (both FLEM's and SELEM's) between 635 nm, 642 nm, 650 nm, and 660 nm reds, and the beam spec difference is always the first thing people notice. Less obvious is the apparent brightness issue, and least noticeable is the color difference, at least to most people.

Adam