Micro G71 Build

[CDBEAM]

I thouht I would post a few pics of a build I just did for a fellow PL'er who wanted a very small G71 head. I used 5X cylinderical lenses to correct coupled with the 2.0mm fL collimation lens. Also because they are so small, I used a LSP adjustable LD mount. Nice tight geometry..... Footprint 42mm x 80mm. I think you would not want to work on anything smaller. These small optics are a PITA to position !!! BEAM

[taggalucci]

Looks nice and compact

These small optics are a PITA to position !!! BEAM

Do you mean the 2mm FLs, or the cyl lenses, or both?

[CDBEAM]

BOTH !!! The first cylinderical is about the size of a large grain of rice !!! That's a PITA... And the very short 2.0 mm fL collimation lens, while demanded by the G71 then requires the use on an adjustable mount !!! Good Luck trying to hit the centre without an adjustable X-Y !! It will NOT happen !! The G71 can be corrected....but there are requirements to do so !! Ah...but the 638 line is fine !! BEAM

[taggalucci]

I've been sitting on one of these g71s for a while now and eagerly await my cyl lenses from Kiyoukan. Seeing the progress and results you guys are getting is giving me photonic itchy feet!

Keep up the good work!

PS might need to procure your services for a couple of acrylic mounts for them Kiyoukan lenses.

[andyf97]

I thouht I would post a few pics of a build I just did for a fellow PL'er who wanted a very small G71 head. I used 5X cylinderical lenses to correct coupled with the 2.0mm fL collimation lens. Also because they are so small, I used a LSP adjustable LD mount. Nice tight geometry..... Footprint 42mm x 80mm. I think you would not want to work on anything smaller. These small optics are a PITA to position !!! BEAM

Duno why you bothered with Lasorbs on those diodes, the diodes are very safe without.

Like the idea of the optical mounts, very neat.

[CDBEAM]

Duno why you bothered with Lasorbs on those diodes, the diodes are very safe without.

Like the idea of the optical mounts, very neat.

Lasorbs= client requested. I did manage to smoke a G71 quite a while ago...careful when you fiddle with LD rotation !! You must position with power on ...but if a joint momentairly goes O/I = POOF/Magic Smoke !! DUH

Yea...Acrylic mounts DO make alignment MUCH easier !!! Clamping the optics = no epoxy....and with me, no epoxy = no fat fingers to get epoxy on the glass !! Yikes. BEAM

[polishedball]

Nice build, what kinda output power?

[CDBEAM]

440mW driven @ approx 575mA. If TE, could push alittle more.

[planters]

Firstly, nice little build. So, your doing contract work now, hmm. Anyway, I just received my lot of the GB correction optics and I discovered something interesting. If the first (neg) lens is positioned too far from the diode collimnator the resulting near field beam is too wide to fit a scanner ie greater than 5mm wide. However, even with a pretty tight quad arrangement that is exactly what I have to do. I solved this with a longer fl EO lens at -25mm FL and this gave me aprox. 75mm to work with and the divergence remains proportional to beam diameter; not better or worse.

I will absolutely have to use a spatial filter with these diodes. The centering operation that the adjustable diode mounts make possible just insures that the spot is symmetrical the wings remain (they just become more symmetrical too).

If they are well sinked they barely become detectably warm at 500ma. Do we have any data to suggest that we can push these a little to a lot harder if TEC cooled. If not, I have a cold cell that can run them down to -40C, but on the other hand they are all now mounted and aligned in my own nifty quad and I didn't order any spares, so this would be a bit of a hassle.. I now think that as they burn out I will replace them with P73's, so the opportunity may never occur.

[CDBEAM]

Thanx, It was a challenge to deliver such a small footprint !! Concerning the Cylinderical GB lenses, yes, there is not much room to slip in the knife edge mirror. Nice find on the EO lens.

It seems as there are ALWAYS trade-off's when working with optics !! And yes, even with masking there remains just a very small amount of vertical wings !!

I think holding the ambient below 25C will benift both the G71 and the P73. This remains to be tested out.

BEAM