O-like 400mw Crown Upgrade Review / Questions

[stanzal]

Hey guys,

I recently received a crown upgrade 400mw green laser from O-like. Shipping was super fast even with regular mail (not DHL or EMS) - Susie sent the laser out Monday July 16th and it got to me in Ohio exactly a week later on Monday the 23rd. Not bad.

First impressions: the laser is very bright. The beam can be seen in a well-lit room and is fairly bright outside at night, but not mind-blowingly so. Divergence seems decent, although it's definitely not as good as the Power Rock 100mw that a friend of mine owns. I'm quite sure that the laser is brighter than the Power Rock, but without an LPM I'm unable to test exactly by how much.

That said, I have a couple questions regarding the laser. Although I know this has been asked a few times before, is there any way I might be able to estimate the power of this laser without an LPM, and without having another green laser handy for comparison (my friend with the 100mw won't be around for a few months)? The only other laser I currently own is a 2.5W 445nm Yob build which I must say is incredibly bright and burns like the best of them. Big props to Yobresal for building such a little monster. I'm pretty sure that comparing my new greenie to the 2.5W would be a highly inaccurate way to estimate its power though... just fyi, the Yob build seems considerably brighter.

Lastly, I've noticed that my laser is relatively inconsistent power-wise. About 1-2 seconds after the laser turns on, it dims considerably - the power appears to get quite a bit weaker than it was in the beginning - and then gets brighter again after a couple seconds. The problem is, the laser never really stabilizes. The longest I've kept it on is roughly a minute, and the power is constantly fluctuating throughout this time period. I took a look at the unfocused dot through my glasses and noticed considerable mode hopping that continues well passed typical "warm up" time. I understand that cheap high-powered greenies are not expected to be very stable, but mine seems particularly bad. I'm currently using the stock battery in the laser, and will consider trying to grab an IMR as recommended in a previous thread to see if that alleviates the problem. Not so sure that it will though.

I've attached a few pictures of the laser along with a couple of my Yob build and a video of the mode hopping. Any help would be appreciated in determining if this laser is up-to-spec or if I it might be worth going through the hassles to try to get a replacement.

:thanks:

video: http://www.youtube.com/watch?v=M-D61PODhwQ&feature=youtu.be

FYI this was filmed on maybe 3/4 filled batteries. I'd been using the laser for roughly the last 10 minutes or so so it was slightly "warmed up."

 

[InfinitusEquitas]

Hi, and welcome to the forum.

Unfortunately there is no way to accurately gauge laser power without a laser power meter. Differences of 100mW+ can be impossible to spot without a reference point even.

You are in california. There are a number of vets who also live there... most of them would be willing to LPM the laser for you, so long as you cover return shipping. I would offer, but I'm on the other side, and kind of super busy right now.

In terms of mode hopping, there is nothing to be done, except to focus the laser to infinity, and ignore it. For pointer purposes, it's not a huge problem.

As far as power jumping up and down, you are on the right track... get yourself a pair of decent IMR batteries and see if the problem is as bad. That laser really should never be used with a shitty xxxxFire battery imo.

 

[stanzal]

Thanks InfinitusEquitas for the welcome and quick reply.

Good to know that it's practically impossible to gauge power without a power meter. I figured that was the case but just wanted to make sure. The main reason I was concerned about the mode hopping was because I thought that that might be the cause of the massive power swings I was experiencing - I had heard, for instance, that different modes can allow different levels of brightness and thus the mode hopping could have been making the "flickering" I had been experiencing.

Just ordered a couple IMR 18650's online. I'll post an update when I receive them to let you know if they've helped.

Also, does anyone know of any beam expanders that will fit onto this laser? (the head is 24mm wide)

 

[2100]

Hi Stanzal, just got my 400mW O-like i think i ordered nearly the same time as you did.

Yeah, initially it did flicker quite a bit. I do not have a LPM but i have a light meter. I am into flashlights much more than lasers and the usual thing to do with flashlights is a ceiling bounce in a corridor with white walls (if you have patience you can do a light integrating sphere). Seems like a ceiling bounce can be surprisingly accurate with lasers actually as the light meter's response is extremely fast compared to a LPM (mine is about 0.2s response time), and of course the "beam" of the laser is pretty much the same.... for flashlights you'd have to contend with spill/differing hotspot sizes. Still it gives you a pretty accurate figure. Actually output differences of less than 20% is literally impossible to tell apart unless you are doing direct A-B comparisons.

My copy draws 2.31A without the tailcap in the way but i think the tailcap would have no issue handling this. I have the O-like 100mW with integrated beam expander and another cheapie HJ-301 greenie.

If I use the O-like 100mW as a reference, it gets me 5.0 on the meter. The HJ-301 is about 2.7 (very stable). Initially with a total runtime of less than 5 mins cumulative, I got readings in the region of 26.0 but now then best i can get is 21.0 range. It does dip a wee bit sometimes to like 15.0 (I presume that'd be ~ 300mW), but generally gives me a decently stable reading after like 20 sec of turn on @ 18-19.0. So the power is right there.

I guess there could be a burn-in factor at play here as well? Can't tell much as mine is still new.

BTW the light meter is absolutely insensitive to near IR. That doesn't tell you much, just that the O-like 400mW beam is not that much significantly more IR than the 100mW.

PS. The mode-hopping/flickering is not a big problem - i read someone's expensive Jetlaser is doing the same thing so i was aware of that before the purchase. And some copies might be more stable than others, i guess? For that kind of price i can't complain and am happy that the power is more or less there.

 

[2100]

BTW for batteries i have a whole myriad of high-end cells, mid end cells, low end cells. As long as they can do > 2A on the meter, i guess it does not matter much when they are fully charged. IMRs are probably overkill, but since you've ordered them then they are ok. A mid-end cell like the XTAR 2600mAh 18700 (its a protected cell) easily gives you 45 mins of total fun time before dropping below 2.3A threshold.

 

[stanzal]

Hey 2100, thanks for the reply - that light meter idea seems pretty intriguing - might need to pick a meter up at some point and give it a try. The main way that I've been trying to judge the power of my laser is by seeing how much it lights up a room when pointed at a white wall. At night it certainly has no problem lighting up a whole room which leads me to believe that it's at least close to spec (my old 100mw definitely couldn't do this). This is also the main way that I've detected the flickering - the brightness of the room changes a fair amount due to the laser's power swings... then again I'm not sure if the amount by which the room's brightness changes is directly proportional to the amount that the laser itself is changing in power, if that makes sense. A couple of the pictures in my OP depict the brightness fairly well, if not exagerating it a bit.

Anyway, my IMR's came in the mail yesterday. As you said, they don't seem to make a huge amount of difference to the naked eye (probably would if I had an LPM, though)... it seems like the flickering has gotten a little bit better but it's definitely still there.

Sounds like you got a nice up-to-spec, if not a little overspec, laser. I feel like mine is probably up to spec, but I guess it's impossible to be sure w/o some type of test. Not expecting anything too overspec, though - I figure with their 500mw offering, o-like would be cashing in on the tremendously over-spec 400mw's anyway by selling them as 500's.

Hi Stanzal, just got my 400mW O-like i think i ordered nearly the same time as you did.

Yeah, initially it did flicker quite a bit. I do not have a LPM but i have a light meter. I am into flashlights much more than lasers and the usual thing to do with flashlights is a ceiling bounce in a corridor with white walls (if you have patience you can do a light integrating sphere). Seems like a ceiling bounce can be surprisingly accurate with lasers actually as the light meter's response is extremely fast compared to a LPM (mine is about 0.2s response time), and of course the "beam" of the laser is pretty much the same.... for flashlights you'd have to contend with spill/differing hotspot sizes. Still it gives you a pretty accurate figure. Actually output differences of less than 20% is literally impossible to tell apart unless you are doing direct A-B comparisons.

My copy draws 2.31A without the tailcap in the way but i think the tailcap would have no issue handling this. I have the O-like 100mW with integrated beam expander and another cheapie HJ-301 greenie.

If I use the O-like 100mW as a reference, it gets me 5.0 on the meter. The HJ-301 is about 2.7 (very stable). Initially with a total runtime of less than 5 mins cumulative, I got readings in the region of 26.0 but now then best i can get is 21.0 range. It does dip a wee bit sometimes to like 15.0 (I presume that'd be ~ 300mW), but generally gives me a decently stable reading after like 20 sec of turn on @ 18-19.0. So the power is right there.

I guess there could be a burn-in factor at play here as well? Can't tell much as mine is still new.

BTW the light meter is absolutely insensitive to near IR. That doesn't tell you much, just that the O-like 400mW beam is not that much significantly more IR than the 100mW.

PS. The mode-hopping/flickering is not a big problem - i read someone's expensive Jetlaser is doing the same thing so i was aware of that before the purchase. And some copies might be more stable than others, i guess? For that kind of price i can't complain and am happy that the power is more or less there.

 

[2100]

Hi Stanzal, well I have a light meter is because of my flashlight hobby so that's just a coincidence. A LPM is still second to none (correct tool for the job) but i guess it wouldn't show the flickering up as number as much as the light meter. (just check out some of the LPM photos. Also it is much noticeable on a ceiling bounce rather than "looking at the dot reflection 10m away...careful here of any reflection).

I guess other than having a meter of any sort beats the naked eyes. But yes a ceiling bounce shows it great. What i know from the flashlight hobby is that the eyes get overloaded by photos after a certain threshold and the pupils' size actually compensates. We get this in high powered flashlights of say > 1500 lumens reflected on a white wall.....

I have done more tests, i used a Sanyo 2600 (UR18650) unprotected @ 4.23V slightly overcharged and it got me 2.45A which is the highest i ever got. The Sanyo 2600 unprotected is reputed to have very low internal resistance hence giving that slight boost. Even the Panasonic unprotected 3100mAh (the NCR18650A) gives me some 2.41A only @ 4.23V. I used another lousier battery at 2.3A.
So with these few cells i put them on a ceiling bounce test on the light meter AND with the Uni-T UT58E w/4-inch 18awg leads as the switch thus measuring current in real-time. What i found is that there is no direct correlation between tailcap current draw and output.

What i found is that the output stabilises after like 15 seconds....it is well over 20.0 (ie 400mW as referenced)....i get 21.x and sometimes 22.x. So it's good.

And even with the tailcap replaced, everything's good and seems that the tailcap switch is not a limiting factor. For flashlights, in some powerful direct-drive lights, some lousier switches are the limiting factor once it comfortably gets over 3 amps.

 

[2100]

And of course I think most important of all is to enjoy the laser.

 

[honeyx]

You guys really should meter your lasers with an LPM rather than with a light meter by guessing which value is refering to 400mW. This is like holding a finger into the air, guessing the temperature and the speed of the wind to make a conclusion to how much solar activity our sun has today.

As long you didn´t meter your lasers and have no exact values for each weavelength to compare with, this will be just pure speculation. Also. The readings of a light meter do not have to be linear like for example 20.0 = 400mW and 40.0 = 800mW.

I also find it a bit strange a 2500mW 445nm Laser is brighter than a 400mW greenie. Oh well, I might be wrong on this, because I acutally do not own a 2500mW blue laser, but by replacing my laserdiode and driver in my 1W laser and getting 1.5W afterwards, it didn´t get much brighter than before. My 500mW greenie is still waaay brighter than the 1.5W blue one.

So either my eyes are just not that sensitive to blue, or the laser on the picture above is simply not near 400mW.

400mW 532 vs. 2500mW 445

 

[2100]

You guys really should meter your lasers with an LPM rather than with a light meter by guessing which value is refering to 400mW. This is like holding a finger into the air, guessing the temperature and the speed of the wind to make a conclusion to how much solar activity our sun has today.

As long you didn´t meter your lasers and have no exact values for each weavelength to compare with, this will be just pure speculation. Also. The readings of a light meter do not have to be linear like for example 20.0 = 400mW and 40.0 = 800mW.

I also find it a bit strange a 2500mW 445nm Laser is brighter than a 400mW greenie. Oh well, I might be wrong on this, because I acutally do not own a 2500mW blue laser, but by replacing my laserdiode and driver in my 1W laser and getting 1.5W afterwards, it didn´t get much brighter than before. My 500mW greenie is still waaay brighter than the 1.5W blue one.

So either my eyes are just not that sensitive to blue, or the laser on the picture above is simply not near 400mW.

400mW 532 vs. 2500mW 445

I understand what you are talking becuase i have done it with 405s and the meter do not measure well with those. Light meters are extremely sensitive to 532. All my figures are with 532s hence that is why i dare to post the figures and I have never posted such figures with my 405s. I can only make reference to the O-like 100mW with beam expander. We do this all the time with different tints in LEDs (from 7 series to 1 series in the tint chart).
All in all, any info is better than no info ie "with the eyes only" or "with the camera". It is not going to be horrendously off.

With my experience of several hundred readings before with nearly 100 lights of varying tints (efficiency of various tints /emitters is well known and documented), the scale down there is pretty indicative, that's the best i can do.

Unfortunately i don't think i'd want to spend 200 bucks shipped for a LPM just for that so-called 10mW or even 50mW of accuracy/resolution. That 350mW vs 450mW (22%) isn't going to be really visibly different, of course for some that matters like day and night as i'd have seen in the flashlight world. (I have seen folks wanting to return stuff for 10% - granted those are dedicated throwers)

Basically what i can say is that when you see it flicker and goes down in power for that 0.1s during initial warm up period, you see the corresponding drop on the meter even for that split second, it's not giving horrendously wrong figures.

 

[2100]

OT a bit and I thought it'd be interesting for the junkies : There was a "survey" done on light meters. Check out the green LEDs. Yes there is perhaps quite a significant variance, but that's for between meters. But i guess in this example the difference in power is 400% on paper, i am able to confirm that on the meter (coincidental or not, i don't know) but not sure what is happening in true life.

Light Meter Benchmark Testing – CPF style


Not sure if there is anything similar done for the LPMs, and anyway is there an official calibration standard? (from what i see, only 2 or 3 models that are affordable being used here)

PS. I also have a HJ-301 that i got for 30 bucks from Manafont, i just know that it's pretty much dimmer than both the O-like 100 and 400mW, and registers correspondingly on the ceiling bounce.

 

[2100]

One last post for those who are after high current/discharge/low internal resistance cells, if you are after such a thing for your high powered 445 builds and are not using 26650/32650. Other than the IMRs, you can go for the Panasonic CGR18650CH, this is like a near-IMR kind of capability but with more capacity. Aparently this cell is safe for use without PCB protection.

Test of Callies Kustoms 2250mAh (Grey)

You can get them from Callies Kustoms/intl-outdoor, just do a google, the info is readilty available from budgetlightforum.

 

[stanzal]

I agree with what you said about the 2.5w 445 vs the 400mw 532. I was expecting the 400mw to be a fair amount brighter. That said, the actual dot of the 532 might very well be brighter than the dot of the 445. I think the 445 could be lighting up the room more in part due to how much bigger the dot is (it has absolutely horrible divergence with a G-2 lens). When shown into the sky, the beams have similar levels of brightness, with maybe a small edge to the 445...

Also, I'm not quite sure how much I trust the brightness meter in terms of our actual human perception of the light. For one, within a specific wavelength, the meter shows a direct linear relationship between power and brightness, ie. a 400mw 532 laser is 4x brighter than a 100mw 532, whereas it's commonly assumed that it would only be perceived to 2x brighter.

Anyway, I figure I'll just try to get it LPM'd. Might try to find someone to LPM it for me, as that would save me some $$...

You guys really should meter your lasers with an LPM rather than with a light meter by guessing which value is refering to 400mW. This is like holding a finger into the air, guessing the temperature and the speed of the wind to make a conclusion to how much solar activity our sun has today.

As long you didn´t meter your lasers and have no exact values for each weavelength to compare with, this will be just pure speculation. Also. The readings of a light meter do not have to be linear like for example 20.0 = 400mW and 40.0 = 800mW.

I also find it a bit strange a 2500mW 445nm Laser is brighter than a 400mW greenie. Oh well, I might be wrong on this, because I acutally do not own a 2500mW blue laser, but by replacing my laserdiode and driver in my 1W laser and getting 1.5W afterwards, it didn´t get much brighter than before. My 500mW greenie is still waaay brighter than the 1.5W blue one.

So either my eyes are just not that sensitive to blue, or the laser on the picture above is simply not near 400mW.

400mW 532 vs. 2500mW 445

 

[2100]

I agree with what you said about the 2.5w 445 vs the 400mw 532. I was expecting the 400mw to be a fair amount brighter. That said, the actual dot of the 532 might very well be brighter than the dot of the 445. I think the 445 could be lighting up the room more in part due to how much bigger the dot is (it has absolutely horrible divergence with a G-2 lens). When shown into the sky, the beams have similar levels of brightness, with maybe a small edge to the 445...

Also, I'm not quite sure how much I trust the brightness meter in terms of our actual human perception of the light. For one, within a specific wavelength, the meter shows a direct linear relationship between power and brightness, ie. a 400mw 532 laser is 4x brighter than a 100mw 532, whereas it's commonly assumed that it would only be perceived to 2x brighter.

Anyway, I figure I'll just try to get it LPM'd. Might try to find someone to LPM it for me, as that would save me some $$...

Hey man, it'd be great for you to meter "the current batch". I am in Asia and it'd probably take 50 bucks to send it to and fro from the USA.

Anyway as a ex-hobbyist + professional photographer, basically your picture is all blown-out or "clipped", what i can see is that your blue has a bigger hotspot than the greenine. That's the short explanation.

Pictures + on-screen comparison is even worse than using the lux meter/LPM.
Even if the data is non-clipped, you'd have to contend with the in-cam procession (saturation matters followed by WB) plus your monitor setting and performance.
For the same beamshot picture with such monochromatic beams, my normal TN is different from my S-IPS and is different from LED TN.
This more or less explains why for some pictures you see on Laserpointerforums, a 445nm might look like a 405nm from another picture, but for others a 445 looks like a 445. Bayer CMOS/CCDs just do not capture these magenta/violet/blue hues nicely.



PS. The light meter that flashlight folks use measures lux or simply speaking intensity of the light. I'll try to focus all 3 greenies to say 6 inch diameter hotspot for all of them and measure the intensity. That'd be another set of data. A lux meter is not sensitive to near-IR, the LPM is...so you'd have to contend with the slight variation % of IR leak between the diodes but it should not be much unless you really have a bad one.

Anyway one of my forum pal shared this, damn cool!

 

[2100]

There are quite a few graphs found here at LPF, but here's a vid.

 

[2100]

I have a 1.2W and 1.8W 445nm, and yes the 400mW is brighter for the beam.

The lux meter shows about 4X difference in green light, but visually the dot is not even 2X brighter between the 100mW and 400mW.....at least for me even at 10-20m distances (i was talking about pupil size earlier on). If you put them side by side very close to each other then maybe so. We experience this with flashlights as well and it's actually a well-known phenomenon. But big difference in beam visibility, of coz.