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CNI PGL-III-M 671nm 150mw *DPSS* Mini-review - PICS

aryntha

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Well, bear with me guys as this is my first review... Some other folks (hey Cmak) specifically asked for this review so I'd figure I'd do my best.

The reason I call this a "mini review" is that I don't own my own LPM yet; I have access to one at a local college campus. (I believe this one is overspec, and I will update the review once I can take it down and test it.)

INTRO:

Some people may ask -- what's the big deal about reviewing a 150mW red laser? Well... This one is a bit unique. This laser is DPSS, as in - frequency doubled, not a direct diode. Its operation is similar to 532nm DPSS lasers, using an 808nm IR pump diode; going through ND:YVO4 - the 1342nm IR line is doubled to 671nm red. (Whereas 532nm green is doubled 1064nm IR; Similarly, 594nm DPSS is summed 1342+1064nm.)

The result of this is a beam quality similar to that of the green 532nm DPSS lasers we're used to: A round, gaussian, clean TEM00 beam, low divergence, and a pinpoint beam diameter.

Manufacturer: CNI
Host: PGL-III-M
Frequency: 671nm
Power: 150mW Rated (Likely higher.)
Mode: TEMoo
Modulation: Pulsed - (Rated 2000hz, but measured 850hz.)
FDA Features: No.
Beam diamter: ~1mm.
Rated divergence: 1.0-1.2 mrad (very good)
Power source: 1x 18650 LiIon

Price: $599, negotiated, but direct quote from CNI is >$1000! (?!?)

The price on this laser, as directly quoted from CNI, and as we've discussed in several other threads in the forum, seems to be a bit inflated -- or perhaps just a product of low demand. The actual cost to manufacture this laser likely shouldn't be much more than a green DPSS laser; the process is just as straightforward (unlike the summing used in yellows.) I'm under the impression that the price I paid was a bit of a 'one time deal', but I'm hoping a group buy could yield this kind of pricing.

THE HOST:

Most people here are likely familiar with the PGL-III-M form factor, also seen as Dragonlasers' "Spartan" packaging. But for completion's sake I'll certainly review the host.

SIDE VIEW


It has a typical "clicky" endcap, which can use a bit of lubrication or DeOxit to make it screw on smoothly. It's a bit 'crunchy' to begin with. Clicky action is "constant on/constant off", however as far as I know, CNI does offer a 'momentary' clicky endcap. There is no battery rattling, and the clicky action is very solid - typical of CNI's quality standards. The laser is rather heavy and solid feeling in your hand; much more substantial than the "maglite" it may resemble.

FRONT VIEW


Here we have the front view of the laser, with the endcap removed. The endcap holds a thin IR filter -- it appears to be rather fragile, so I'd stay away from it and try to avoid having to clean it. As we can see looking into the uncapped laser, the construction is typical of DPSS lasers, with the final lens mounted/epoxied to the round aperture. Not something you normally see in a red laser. During normal operation there should be no reason to remove this cap.

CHARACTERISTICS:

Now for some characteristics of this unique red laser. The comparison metric here will be with the o-Like 650nm "New Style Dilda" laser; this particular one which was measured at 212mW. Note the apparent brightness between the two seems to be almost identical - which is why I believe the CNI DPSS 671nm is outputting more than the rated 150mW.

SHORT DISTANCE BEAM COMPARISON


Here are the beam spots at only three inches or so. On the left is the o-Like, on the right the CNI DPSS. (These "star patterns" emerging from the spots were not actually evident; this is an artefact of the camera's aperture being stopped down and focusing on a point source - you're seeing the shape of the aperture formed by the six blades in the lens.) The first thing that's noticed is that the exit diameter of this red laser's beam is MUCH smaller than any direct-diode red laser. Where the o-Like's beam diameter on aperture exit is around 4mm, the CNI DPSS is sub-1mm.

LONGER DISTANCE BEAM COMPARISON


Here are the beam spots at approximately 25 feet, on a white wall. What's noticeable here is the cleanliness of the beam compared to the o-Like direct diode. (The o-Like was focused as fine as I could get it; the CNI DPSS is non-focusable, but did an admirable job anyhow.) "Wings" and "rings" are common artefacts in the beam of a direct-diode laser; this can be seen on the left in the o-Like's beam. On the right, we see a nearly perfectly gaussian, round, clean spot with no funny business. The beam quality is almost as good as a HeNe laser. (Note that the 'ghost spots' to the left of the o-Like and to the right of the CNI DPSS are due to internal reflections between elements of the camera lens -- they were not actually there.)

BEAM SPOT CLOSEUP


Another view of the DPSS beam, showing how clean it is.

PULSED PROFILE


Like most 473nm DPSS lasers, this laser is a pulsed system. CNI stated 2000hz, but this image was taken at 1/50th of a second, showing 17 pulses. This measures out at 850hz. Either way, the effect is very striking and almost "electric" when the laser is moved around. When the laser is still, there's no perceptual flicker. To me this is just another point in its column for uniqueness -- there aren't very many bright, pulsed red lasers around. The sort of 'buzzing' effect this gives visually when moved is pretty attractive. Combined with the attention-getting deep red (but still VERY bright) color of the beam, it definitely would turn heads.

DAYLIGHT OUTDOOR SHOT


Just to drive home the point that this is not a dim laser, and how good the divergence is, this is a shot across the yard at about 100ft, zoomed in with my camera. Notice the beam is still circular, and the spot is very visible in daylight.

BURNING:

Well, there's always someone who wants to know, "Yeah, but how does it burn?" -- The answer? Surprisingly well. Another reason why I need to get this measured, as I still think it is more than 150mW.

SIMPLE BURNING


With a non-focusable red laser, you'd think it might be tough to get stuff to burn. Not so with this laser. Any dark surface it's pointed at begins to smoke within 1-2 seconds. No need to adjust how you're holding it, or hold it still. It burns VERY well, honestly better than the o-Like 212mW, which is a curious aspect. This makes me wonder if there is a good amount of IR content in the beam. There IS an IR filter, but either this is quite overspecced (perhaps evidenced by its apparent brightness equal to that of a 212mw 650nm, while at 671nm) - or there is some IR content in the beam. In any case, it's a real champ of a burner.

LIGHTING MATCHES


"Can it light matches?" -- easily. I didn't even have a very steady hand during this shot, holding the laser next to my camera's lens, trying to hold the whole setup steady. I managed to get the beam onto the head of the match from about 3 feet away here, figuring I was too far away. Not so much. The match lit about 1.5 seconds after getting the beam on the head of the match. This was a blue matchhead. Red may give you more trouble. But this laser handled the job, no problem.

BEAMSHOTS

Here are some beamshots -- I'll likely add more as I take them, but some in-room ones with minimal smoke is a good start.

These shots were taken after lighting 2-3 matches and letting them smoke out.

ROOM LIGHT


Here's an example comparing the o-Like's beam (left) to the CNI DPSS (right). The thickness of the beams are likely due to focus issues and where the camera's autofocus decided on. In reality, they are thinner. Something interesting to remark: The DPSS's beam seems just a slight bit "pinker" than the o-Like's in the camera shot. However, in actuality, this is somewhat inverted - To the eye, the o-Like diode appears more orangeish (even at 650nm) whereas the CNI DPSS appears a deep, 'rich', 'pure' cherry red. It does not appear dimmer - mostly just "redder". But I have to wonder why the camera shows the beam as more "pink', again possibly due to IR content, but I'm not sure.

Note, I also have to remark that in addition to the "redness" of 671nm, it seems to me that the output from the DPSS laser is much more monochromatic. Close up, looking at the spots and beams, compared to the DPSS 671nm, side by side, the o-Like 650nm diode appears "more like LED light" than the DPSS beam does. As if it has more frequency components. (The 'laser speckling/scattering/grainyness' appearance is much more evident in the DPSS. The Diode light seems more 'smooth'.)

DARK ROOM SHOT


And here's a beamshot comparison in a darkened room. Again, sorry about the focus issues -- I'm still getting a hang of beamshots.. But here, while the beams are a bit widened due to camera shake - what IS evident is this "camera-sees-it-as-pinker" phenomenon with the DPSS laser on the right. The beams certainly look different and are different both on camera and to the eye.

... I will likely add more beamshots (outdoor, etc) here when I can; but its 1:38 AM right now and I wanted ot at least get some of the characteristics of this laser out to folks who were interested in it!

OUTDOOR NIGHT BEAM VISIBILITY


A question that I've seen asked often is, "Is the beam visible outside in the sky at night?" -- The answer to this is, yes, absolutely. Looking in the direction that the laser is emitting (usually the hardest direction to see the beam from) - the red beam can absolutely be seen in the night sky. Pointing it off of my back deck in the picture above, the PGL-III-M-671 is being shined onto a mountainside across the valley, about 600ft away (estimated) - onto a patch of snow that hasn't melted yet. (which is why you see the bright red spot at its target.) -- The camera was about five feet to the right of the beam, so that's why it looks like the beam is actually being pointed towards the camera -- it isn't. This is looking "in the direction of the emission of the beam" in the clear night air. The beam is absolutely visible, with no perceptible fog in the sky. (The same scene with some daylight (Note - Different lasers in this shot! Not the CNI DPSS!) can be seen in my old Orion HV thread here - where you can see the snow patch that forms below the trees; thats where this laser is targeting in this shot. )

CONCLUSION:

Overall, I'm really happy that I got this laser. It's a bit of a rare specimen, and it's certainly a heck of a break from your normal diode PHR or Dilda.

The color of it, the pulsed aspect, beam profile, divergence, build quality, and uniqueness of process definitely makes a great addition to my collection. If anyone wants a REALLY high quality red laser, I'd strongly recommend this one -- if we can get them for a cheaper price. I believe we could, if interest was there. Though there may not be that many people looking for a DPSS red laser.

(Hopefully this first quick review was an interesting read, at least!)



Thanks,
Aryntha
 
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Gryphon

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Sweet Review! I always did like the thin beams you get with a dpss setup
 

RA_pierce

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Great review. Can't wait to see some power tests.

I think that there should not be any IR in the beam.
CNI's IR filters are pretty good. If there is any IR in the beam, it will certainly not be measurable.

I think that the pinkish hue of the 671nm laser on camera may be due to the longer wavelength.
780nm and 808nm appear pinkish or purplish on most cameras I have used.

As a side note, I think the Dilda is closer to 655nm. On the diode spec sheets for the LOC and LCC diodes we use, they are both listed as 655nm.
 

x90z75ek

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Very good review!
I had no idea 655nm and 671nm would be that different in color.
I would expect this laser to be at least 240mW since it's almost as bright as a 212mW 655nm.
 

aryntha

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It certainly burns better than the Dilda, even though the beam cannot be focused to nearly as fine a point. So I'm leaning towards this. It's a very bright laser.
 

Meatball

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It would be interesting to see a 635nm unit lined up next to this PGl and a 655nm LOC. The "red" bandwidth is much larger than I normally think of it as.
 

aryntha

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Meatball,

I've got a 635nm PGL (Orion) - but its ~350mW and multimode, so I don't know if it'd be a fair or "apples to apples" comparison.

I can post any requested pics you may want though.
 
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Wow, sweet dude, I just now saw this review! I would like one of these as well, though maybee in the PGL III A or C host instead, but really cool and very unique. Belive it or not red is actually one of my favorite wavelenghts, I like it much more than green, though not as much as 473nm and probably 589nm(once I see it that is)
 

aryntha

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Would have LOVED to get it in a -C, but the price was just too ridiculous. Either way, one of my favorite lasers, really, the way "red should be". I'll try to get some divergence ratings and follow up here this week.

Also planning on doing an overview of my Novalux 488 DPSS here soon.
 
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Man, I gotta say, you have one AMAZING collection, if you ever put your lasers on display somewhere i'd pay to go see them....:D
 

DJNY

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:bumpit: cause I like this review so much

and I´m sure some of the newer members haven´t seen it yet :D
 
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532 with Envy

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This is a great review! I didn't see it before.

You've got yourself a pretty rare laser there. Although I don't think I would spend that kind of change on one, I am finding myself a bit jealous.:shhh:
 




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