New 1 watt O-like DPSS red laser

[AAlasers]

Hi everyone, interesting find:
1W/1000mW DPSS Red laser module [OL-R-1W] - $369.99 : Welcome to O-Like.com, Your source for laser products

Doesn't it seem impractical to make a 1W 650 red with 4mrad? Why not combine 4 250mw diodes, or more realistically, use the new 638nm diode?
Either way, it looks quite interesting, someone should buy one and make a review.

Input is appreciated,

AAlasers

 

[Grix]

Almost all high-powered reds have flashlight divergence. Also I don't think this is really DPSS.

 

[millirad]

The whole idea of having a 1W red is thrilling, until you look closely at those specs. Yeah, someone who knows if this is really a DPSS let us know. It's intriguing. Susie?

 

[Xtrm2Rick]

i wonder how they got 650nm with dpss, also wouldn't dpss give way better beam spec's then they state on their site?

sounds more like a multi-mode diode or a few diodes combined..

 

[goninanbl00d]

If it tastes like a duck, quacks like a duck, and waddles like one, it's probably a duck.

Now, if it were DPSS it'd be either 660 or 671nm. Nor would it have the 4mRad divergence, and horrible beam diameter at aperture.

PBSing diodes would be impractical- you just can't fit the optics required into such a small module. It can be done for a larger module, but it gets to a point where it's just no longer practical to keep throwing diodes at it. Besides, two single-mode diodes combined would give identical beam specs to a single diode.

Besides, once you get past two diodes, you're going to have to knife-edge. Knife-edging without telescopics results in a messy beam that looks like something a poorly-aligned DPSS cavity would poop out on a rainy day. Knife-edging also involves sensitive alignment, and that just adds build complexity, bringing up the price even further.

As for the new 638nm diodes? You ain't getting that power for free. These are multi-emitter, multi-mode diodes. These diodes have beam specs that make 445nm multimode diodes look good. Even with correctional optics you still end up with horrible divergence and a poor beam profile.

What this *is*, however, is a 1W C-mount diode in a heatsink assembly, along with some basic correctional optics and a collimating lens.

That's how they got so much power down into such a small size. You really can't get much better, 3mRad is usually the minimum divergence with these.

 

[HIMNL9]

Anyway, one thing is strange, in the specs .....

"Over heat protect
LD heat sink temperature gets to 32℃，LD power cut off ,cooling performs Best .
When LD heat sink temperature drops to normal working temperature .LD power restart "

Which normal diode requires a overheating cutoff at 32 C ? ..... at this temperature, any 1W diode is normally considered "cold" .....

 

[villalaser]

Anyway, one thing is strange, in the specs .....

"Over heat protect
LD heat sink temperature gets to 32℃，LD power cut off ,cooling performs Best .
When LD heat sink temperature drops to normal working temperature .LD power restart "

Which normal diode requires a overheating cutoff at 32 C ? ..... at this temperature, any 1W diode is normally considered "cold" .....

From snoctony
1000mw 650nm laser diode C-mount /To-3 package - eBay (item 120653852408 end time Dec-29-10 06:47:27 PST)

Parameter: Sn650T1000mw
CW output power(Mw): 1000
Peak wavelength(nm): 650+/-10
Spectral width(nm):[FONT=&#23435]≤2.5[/FONT]
[FONT=&#23435]Threshold current(mA):[FONT=&#23435]≤1450[/FONT][/FONT]
[FONT=&#23435][FONT=&#23435]Operating current(mA):[FONT=&#23435]≤2500[/FONT][/FONT][/FONT]
[FONT=&#23435][FONT=&#23435][FONT=&#23435]Operating voltage:[FONT=&#23435]≤2.5[/FONT][/FONT][/FONT][/FONT]
[FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435]Slope efficiency(W/A):[FONT=&#23435]≥0.9[/FONT][/FONT][/FONT][/FONT][/FONT]
[FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435]wavelength temperature coefficienc(nm/[FONT=&#23435]℃):0.25[/FONT][/FONT][/FONT][/FONT][/FONT][/FONT]
[FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435]Beam divergency(deg):42x10[/FONT][/FONT][/FONT][/FONT][/FONT]
[FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435]Emitting area([FONT=&#23435]μm):200x1[/FONT][/FONT][/FONT][/FONT][/FONT][/FONT]
[FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435]Operating Temperature:10~25℃[/FONT][/FONT][/FONT][/FONT][/FONT]
[FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435]Storage Temperature: -10~60℃[/FONT][/FONT][/FONT][/FONT][/FONT]
[FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435][FONT=&#23435]Lifetime(h):10000[/FONT][/FONT][/FONT][/FONT][/FONT][/FONT]

 

[Cyparagon]

Look at the SIZE of that beam. It's not DPSS, and probably not 650 either. I'd put my money on 660.

 

[HIMNL9]

From snoctony .....

..... Operating Temperature:10~25℃ .....

Uhm, i understand this for single mode, holography emitters, cause the wavelenght and modality changes when the temperature change, so for a similar delicate application field is normal ..... but i doubt that this particular diode can be 1W single-mode holography diode ..... not with a 200x1 emitter, and not for 450$, at least (but i can be always wrong, in this )

 

[Grix]

and probably not 650 either. I'd put my money on 660.

Manufacturers generally call all high-powered reds 650nm, even if they really are around 655-660nm.

 

[Benm]

Well, the wavelength is often stated 650 +/- 10 nm, so it would be within spec at 660 nm. But i'm quite sure this is not a dpss laser. Not only are the beam specs bad, 650 also is not a dpss wavelength at all.

The only commercially viable dpss red line is 671 nm, but thats pretty dim for a give power. There are 660 and 656 dpss lines available, but they are expensive.

 

[Emc2]

It's most likely a square beam, the divergence is probably not all that bad. High power red lasers usually have a square spot instead of a round one. The red laser systems that Jack sells at Optotronics have square beams, I think that is so because of four red diode lasers merged into one beam.

Todd

 

[HIMNL9]

The "squared" beam make me think about a multimode diode, yes ..... if you see, those diodes have a rectangular shaped beam from the emitter, with the fast axis very large, but using a FAC lens, you can get a "squared" image, squeezing the fast axis to the same divergence of the slow one (usually, you get a square made with stripes, from the multi emitter) ..... so, yes, also the focused beam can be squared, if a big frontal lens is used (so-called fat beam )

Also, about the divergence, 42 x 10 degrees ? ..... anyone have ever seen a DPSS with similar fast and slow axis ? (especially considering that in a labby unit, the fast axis is always corrected, before shoot the beam in the nonlinear crystals ?)

So, now i'm confused ..... but yes, it smells always more as a diode

 

[goninanbl00d]

It's most likely a square beam, the divergence is probably not all that bad. High power red lasers usually have a square spot instead of a round one. The red laser systems that Jack sells at Optotronics have square beams, I think that is so because of four red diode lasers merged into one beam.

Todd

Yes, it's a square beam profile. At aperture, it's a rectangle, but it quickly becomes a near-square after you give it some distance and let both axes diverge.

It's not like the 445s, they only give one divergence value. This either means they've got inbuilt correctional optics or they're quoting the divergence value for the less-divergent of the two axes.

The reason why they have square or rectangular beam profiles aren't because they're multiple diodes combined.

Combining two diodes creates a beam profile identical to the worse of the two diodes combined.

Combining 4 or more creates either an oval or round beam profile, depending on the telescopic lenses used on the final output.

These modules use a single multi-emitter, multi-mode diode.

That's why they have horrible divergence and even-worse beam specs.

EDIT: HIMNL9, you can't physically get such a demented output from a NLO or a gain medium. Even if it were running in TEMwtf, it wouldn't nearly as divergent, nor as regular.

 

[HIMNL9]

EDIT: HIMNL9, you can't physically get such a demented output from a NLO or a gain medium. Even if it were running in TEMwtf, it wouldn't nearly as divergent, nor as regular.

Yes, that i was meaning ..... never seen a DPSS with similar characteristics .....

 

[Cyparagon]

Well, the wavelength is often stated 650 +/- 10 nm, so it would be within spec at 660 nm.

That's not how specs work. If I tell you they're 650, and 98% of them are >658, I need to rethink my rating. It is supposed to be on a normal distribution.

All of the "650nm" lasers I've measured are >655nm. One was 663nm. That is a big difference in brightness.