Mitsubishi ML520G71...Red Holy Grail or Flashlight Fail ??

[planters]

Badger,
Please resist the temptation and stop encouraging him.

Jon,
I do think this compressed knife edging could be applied to the 445s as well, if it works.

CD,
Moving the diode mounts around may prove useful because unlike the current state of the art with nearly parallel beams, as long as they are in roughly the same plane it does not matter where they intersect. But, with a focal point the two beams, call them the primary and the perpendicular, they will have to arrive and combine at a specific intersection point.

kiyoukan,
The FL of the cylinders will need to be optimized. Very short and although this will allow aggressive overlap it will require more precise alignment and probably re-focus of the composite primary each time a new perpendicular is added. Very long and the inherently, highly divergent beams will not reach a small enough spot size to allow useful overlap. I don't have a clue as to where to start.

[CDBEAM]

PT...I understand....YES..... Y translation for the LD mount my be demanded for the main and perpendicular beams to be brought in perfect focal relationship.

My work continues on the latest iteration of the Adjustable Diode Mount LDADM V7...work in progress. See pics. I assume the abillity to precisely adjust the LD remains a desireable option.

How to add on precise Y translation is challenging and will likely involve a 100 TPI position bolt !!! BEAM


Note: The build pics show the brass block with the center bore thru of 8.5mm. I still need to cut the block and machine the cut surfaces to produce the 12.7mm Clamping Segment and 12.7mm Component Segment. Work in Progress !!

[dsli_jon]

See if you can render up some grafix..

Oh yeah? Well, let's 'take it outside', fella.. http://www.photonlexicon.com/forums/...088#post227088
..cya there..

...sorry fer the extra, uh, 'pollution', Gents! ..carry-on with the fine werk...

PS - @ Sir Eric - indeed, we will watch this thread with keen interest, towards that end.. indeed, it's too-bad the amazing 'micro-FACs' are not more obtainable, ie: http://images.vertmarkets.com/crlive...7694F32/f2.gif - it would be great if we could rally a massive GB, once an 'ideal' lens could be spec'd / OEM-sourced.. Anyhoo.. back to the G71-channel..

j

[planters]

CD

I am assuming you are discussing the X/Y mount in passing and not as a beam positioning solution.

I do not want to discourage your development. But, the value of a diode adjustment prior to the 2mm collimator is to minimize a whole host of higher order aberrations in the down range beam and because of its short FL there is really very, very little DOF in its positioning to allow the beam to be redirected. Not unless the diode AND the collimator are both adjustable AND there would have to be a tilt adjustment as well, would this work. Because the Y adjustment for this knife edging operation is not required I still think a fine screw driven slide adjustment of the whole diode mount will be simpler. Or if the FL of the first compression cylinder is long enough to allow a little freedom in its position without introducing too many aberrations then the adjustment of this lens might be best. This lens will have to be adjusted in any case to fine tune far field focus.

[CDBEAM]

Yes...I am verifying that we still agree that the abillity to adjust the LD relative to a fixed collimation lens is a "stand alone" desireable abillity to minimizae abberations....and is not intended as a alternate to Y translation of the LD mount. The Y translation of the LD mount is an additional refinement needed for ..." Between C Lens " knife edging. After reading my above post again...Sorry for not making that clear.

BEAM

Note: Jon/8ull...Thanx for SA/FA thread....This is a difficult topic to grapple with....well....for me it is !!

[planters]

Been thinking....surprise. There may be a simplification/shortcut to the the growing,daunting task of alignment.

Start big then go small.
Although too bulky for a practical projector in the long run, imagine starting with the first collimator at 50mm FL. Now, and here is the $64,000 assumption, the profile of the vertical stripe will be narrower for 50mm before and 50mm after the focal point. It will certainly not be symmetrical about the focal point due to accumulating divergence, but narrower, and much narrower around the focal point. The next diode, the perpendicular, will have an identical 50mm collimator doing the same thing to its beam. When the two beams intersect they will have a significant depth of focus to meet within and be knife edged within. In this case, the depth of focus will be great enough to minimize or eliminate the need to fine tune diode mount position and even great enough to allow a second and maybe a third perpendicular to be added without any additional optics (other than their own 50mm compression cylinders). The distances between each of the compression cylinders and the down stream 50mm re-collimating cylinder have to be identical and this is accomplished by setting each subsequent diode mount/compression cylinder with an appropriate set back.

Such a long FL is a trade off against an even tighter vertical stripe and if too long it will not compensate for the divergence in the beam and in the extreme case will not even narrow the stripe before focus and will worsen spread after focus. I don't think that we are any where near there, however.

If workable, the requirement for a good tip/tilt, X and maybe Y knife mirror mount remains to take advantage of the thin vertical lines of these beams.
The correction optics after combining will still be needed, possibly unchanged.
I plan to test with these optics and I will add them to an order to Edmond tomorrow. Sometimes I feel like I must be one of their largest customers, me and Europe

[steve-o]

Edmund has a side-division called "Anchor optics" which is a cheaper "hobbiest" place to buy some of their stuff. The selection is not quite as large. Just a FYI for anyone ..

http://www.edmundoptics.com/company/anchor-optics

[planters]

I've used them. Good prices. A little iffy on selection and proportional on their quality, but a good option when trying to narrow down a solution experimentally.

I think I may have had too much coffee...

I think I have a solution to the Y adjustment issue as well as the conundrum of focal sweet spot vs module size; two stage knife edging. Place the first knife of each pair just after each compression cylinder and use it just for the benefit of one of its axis. The output, running at a right angle to the diode beam then will allow the equivalent of a "Y" adjustment. Furthermore, these first stage knifes can be placed much closer together than the diode mounts and will allow multiple perpendiculars to be added by the second stage "super knifes" within a small distance of each other.

There is a post in the buy/sell about knife PRISMS for 445s and a possible future GB for red. This might be a good idea. If the stripes are reduced to the level of a few hundred um or less the knife edge will have to be absolutely parallel to avoid loss and shadowing. Prisms will be easier to glue up on the mount with extremely precise alignment. And as Jon suggests, if their edges are superior to mirrors...well that's where all the magic is happening.

[planters]

A slight variation on the earlier design that I think will give more room to compensate for the effects of progressive divergence.

[kiyoukan]

Well planters i would love for someone else to try that setup.
I did and it drove me mad.
The spot that you are focusing on and so many other factors made it near impossible to get perfect.
If any of the c-lenses moved even a tiny bit they cause that point to move a good deal.
You need a rock solid setup even just to test.
In my tests i also had a very very hard time getting the beam to stay together it would be either together nearfeild and off far or the other way.
After so many hours and days of fighting it i decided that it was not going to be as stable.