"635nm" vs 650nm

[aryntha]

So, DJ - interested to know... Was this 30mW from China definitely *NOT* 635nm, as compared to the AtlasNova?

 

[DJNY]

So, DJ - interested to know... Was this 30mW from China definitely *NOT* 635nm, as compared to the AtlasNova?

Yes I´m sure it is not 635nm.
You can read Robin´s statement if you want to:

Hi Robin,


I´ve tested the "30mW 635nm" intensively the last days. I give you the chance to know the results before I write my review on laserpointerforums.

I can tell you that this laser failed at the power output and wavelength tests. First of all I was wondering that there was no visible difference between my 50mW 650nm and the 30mW 635nm. I´ve done several tests, for example shooting the two lasers along a wall and with steam.

The next test was with a diffraction grating. As you know, the further the space between the dots, the higher the wavelength. Once again, no difference.

I did the same test with a 200mW 650nm red and a 5mW 635nm Atalsnova. There was a clear difference and the 5mW real 635nm was much more visible than your 30mW "635nm".


As a last resort I did the power teston my HLPM II I. I noticed an average output of around 16,3mW and it peaks at 17,2mW.


After I write the review I want to send you the laser back and ask for a refund, because the laser isn´t the laser you promised me.


Best Regards,
phi

Dear phi,



We are very surprised on your test results,but we have some objections on the results.



1)the light of 635nm wavelength is lighter than 650nm based on the same output power,but our 635nm is 30mw,and your 650nm is 50mw.

That is to say,it is possible that 635nm 30mw of light is nearer than 650nm 50mw.

2)Diffraction grating have a large tolerance,the wavelenth of 635nm and 650nm have +-10nm wavelength tolerance,so the actual wavelength fall on a point on the random,it is possible the actual wavelength is nearer for 635nm and 650nm.But diffraction grating did not find this.

3)Due to the temperature and battery capacity is different,and the tolerance of your test equipment is large,so the output power you tested is not exact, the actual output power of our 635nm 30mw red pointer should be >23.5mw.



Please test it again!



Best regards!



Robin Meng

Shanghai Sail Laser Technology Co., Ltd.

 

[daguin]

So, DJ - interested to know... Was this 30mW from China definitely *NOT* 635nm, as compared to the AtlasNova?

Yes I´m sure it is not 635nm.
You can read Robin´s statement if you want to:

Although it is hard to discern in isolation, once you have a 635nm shining next to 650nm, the difference is easy to see. Sorry that company is giving you the run-around.

Peace,
dave

 

[aryntha]

DJ,I'd perhaps suggest to Robin that there has been a mixup. Maybe suggest that by mistake, a 650nm was sent to you in error?

Perhaps she could send you a pointer that she is SURE is "30mW, 635nm" ?

Who knows. Maybe a diode, a label, or a bin or batch number got mixed up somewhere. Give her that opportunity, suggest it, maybe it's the truth, even.

 

[cmak]

man the thing about the red end of the spectrum is that there are SO many different diodes and so much variation in them that they tend to all practically blend together at times. Just to name a few common configs, there are 656nm, 660nm, and 671nm DPSS modules; 635nm, 640nm, and 655nm DID lasers; and even more variants the closer you get to IR. The biggest issue however is that the DID's have a HUGE amount of variation in the exact wavelength so sometimes you get "freak" diodes where 635nm can be around 643nm, and 640nm can be around 632nm, and 655nm can be around 648nm, and then try figuring out which is which without an LPM.

and if that wasn't enough, most of the aforementioned (635nm, 640nm, 655nm, 671nm-DPSS) lasers are widely available and in portable/pen form.

peace & thanks
-cmak

 

[DJNY]

I don´t know why so many people say that the eye isn´t able to distinguish red from this clear tangerine. Maybe it is a problem of the older generation that their eye isn´t so sensible for color deviations any longer!?

 

[aryntha]

I don't think color acuity goes away with age. Focus/contrast/nightvision, yes... But some people do have color issues to begin with.

i've always been able to see that difference between 650 and 635 pretty easily. Though I did have a friend over who couldn't tell the difference between my 612, 635 and 650. I find that kind of odd.

 

[Cyparagon]

I bought a 635 pointer from ebay a few years ago. Turned out the seller saw on the label "635-670nm" and just listed it as 635.

 

[daguin]

I don´t know why so many people say that the eye isn´t able to distinguish red from this clear tangerine. Maybe it is a problem of the older generation that their eye isn´t so sensible for color deviations any longer!?

I don't think color acuity goes away with age. Focus/contrast/nightvision, yes... But some people do have color issues to begin with.

i've always been able to see that difference between 650 and 635 pretty easily. Though I did have a friend over who couldn't tell the difference between my 612, 635 and 650. I find that kind of odd.

As the eye ages, the cornea becomes more "yellow." This does effect color perception. This could cause a slight "orangeing" of red. However, for us, it is really only a problem in the violet (bluray) range. Yellow blocks violet :cryyy:

Peace,
dave

 

[kingdave2357]

I just bought one of those 635nm atlasnova's cant wait to add it to the collection

 

[Raybo]

As the eye ages, the cornea becomes more "yellow." This does effect color perception. This could cause a slight "orangeing" of red. However, for us, it is really only a problem in the violet (bluray) range. Yellow blocks violet :cryyy:

Peace,
dave

Dave,

My "old" eyes are quite different, I have no problem with the cooler colors but the warmer colors (especially red) just play heck with my eyes.

I'll try to image a compairision with my 650 and 635 for your viewing pleasure.

Ray

 

[DJNY]

I´m quite sure that I have this laser: http://www.cnilaser.com/PDF/GLP-640.pdf
Even if it isn´t 635nm, it is a nice, heavy, good looking laser + I really like the case of this laser.

 

[DJNY]

BTW does anyone know something about this diode: RLT635-500-TO3, 635 nm, 500 mW, mm, TO3

 

[daguin]

http://www.roithner-laser.at/All_Datasheets/Laserdiodes/RLT635-500-TO3.pdf

Big, wide, multi-mode beam with huge divergence, in a TO3 package

Dave,

My "old" eyes are quite different, I have no problem with the cooler colors but the warmer colors (especially red) just play heck with my eyes.

I'll try to image a compairision with my 650 and 635 for your viewing pleasure.

Ray

I would say your situation is more caused by your being a man than being older. Men are far more likely to experience some measure (mild to severe) of color blindness than women. Actually, compared to women, ALL men are color blind The red/green color blindness is very prevalent, especially in milder forms. This may just be the first time in your life that you had a situation where you noticed it

Hmmmm . . . . I wonder if this is one of the reasons that males are more impressed with lasers than women. Women see a much more color rich environment than men. Maybe the intensity of laser light allows men to see something that women "see" all the time . . . . . :thinking:

Peace,
dave

 

[Benm]

Any such yellowing must be quite severe to interfere with color perception though.

Our eyes have a auto-white-balance mechanism builtin, since the sensitivey for reach of the color receptors is regulated by their respective activation. I'm sure we are all familiar with this - if you play with red lasers in a dim environment for while, you'll notice that afterwards things look greenish, and red objects appear dull. This compensation normally happens over a span of a few minutes, perhaps 10 or 20 in extreme cases.

When people wear colored contact lenses (to change apparant eye color) they also adapt to the filtering quite quickly and will see things in normal color after a short period of time.

 

[cmak]

thanks for the wonderful insight, Dave; that's quite interesting and I never really thought that maybe females have different perceptions of color than males do...

peace & thanks
-cmak