cylindrical lens pair vs anamorphic prisms?

[catalanjo]

Hmmm... I just cannot believe.....we have been " stuck " on this MM 63193 Red....ALL this time....and nothing new....for what 2+ years....wow !!

Not necessarily .. see http://www.photonlexicon.com/forums/...D-638nm-1200mW

Maybe a RED herring, (pun intended), with double emitter width as Phillip suspects, ...but until someone tests it properly to demonstrate this detail, since Hitachi often makes good stuff, there is still a glimmer of hope.

Cheers

[catalanjo]

I think you are spot on mate!
Reading that, makes all the long winded earlier posts worthwhile.
Best of luck with the build.
Cheers
PS. Optics plate would be better without any fins absorbing heat from the surrounding air .

[catalanjo]

In CPC ...(no shipping charge above £10)... you can get UK mains plugs (among other things) with fuse,switch and neon on the plug itself (incredibly useful)
Cheers

[catalanjo]

I got one more question...What causes the laser beam to "Twist" in mid air...at the module its coming out vertical but 20m away and its horizontal?

The beam come out of the bare diode as an expanding oval (elliptical) shape, with one axis expanding much faster than the other. This gives rise to the denomination of "fast" and "slow" axis.
I the fast axis is in the vertical plane (advisable if cylinder lenses are to be used later to correct the beam shape) then the slow axis is horizontal.
When the beam goes through the first (collimating) lens both axis are affected by the same amount by this aspheric lens which is symmetrical about the beam centre axis so that it can be focused to achieve the smallest possible vertical spot (image) at long distance.
This has the unfortunate effect of over correcting the horizontal slow axis so that it focuses to a vertical line very close to this first lens, and from there on, starts spreading horizontally whereas the vertical originally fast axis is now almost parallel. This means that the vertical small line close to the diode stays small in the vertical plane but gets progressively wider in the horizontal plane.
When you put a cylindrical lens pair (or a prism pair) in the beam path, the initially very thin line is made fatter allowing it to be focused at distance at the cost of larger beam width close up.

This crossing over geometry only seems mysterious due the the fact that it initiates so close to the first lens as to make it almost invisible to the naked eye since it is very very intense at that point and produces too much glare to distinguish what is happening. This also gives rise to many people misunderstanding the denominations of "fast" and "slow" axis since they rarely see the beam without the first collimating lens and therefore the names appear to describe the opposite to what they can see, making them forget the existence of the collimating lens and assuming fast and slow axis to be the opposite of what is being described by others who ARE aware of the effect of the first lens.

Hope this helps!
Cheers

[catalanjo]

Yes, but this is just the laser diode without the collimator lens.
cheers

[kecked]

Nice job. Looks like your moving along. I think you will have a nice unit very soon. Then like a nuke the task is shrinking it down as small as possible. I was able thanks to a lot of help to bundle an entire 30k (506 3mm) 500mw projector in a 6" cube including supplies and drivers and optics. The optics deck fits in 1/4 the palm of my hand and includes all mirrors and dichro. This was made for me. I didn't make it. I'd give the name of the person on here that did it but I don't want to post it unless they want me to so they don't get 1000 emails. If they see this and want to post they will.

Anyway good job you nailed it.

[ZeroPoint]

Funny you should mention liquid cooling, I was just thinking about doing something like that with a projector. My computer is liquid cooled so i figured the same tech can be applied to projectors. AlphaCool might be worth checking out in the future for custom liquid cooling loops.

Edit: I forgot the alphacool website is german. Aquatuning.us would be the site I was referring to in english.

[catalanjo]

I've decided Im going to take this module apart and start again but this time with a single diode and proper cooling(a single TEC with the cpu cooler) I cant afford liquid cooling right now but hopefully this will work this time

The CPU cooler you are using IS liquid cooling ! ....not only that, but it is currently the most advanced version of liquid cooling available, using crude nano technology and "state" induced liquid transport (heat pipes)! This is a similar method that our planet uses very effectively as temperature regulation of its surface. (although without the "tubes" but making use of its rotation.

However your cooler, has been designed for a certain common type of computer structure, (therefore allowing it to be cheap), and as I pointed out earlier, this makes it a bitch to fit into a projector.... in fact you probably will have to design the projector to fit the cooling system instead of the other way around.

This isn't as silly as it sounds since efficient cooling, is much more dependent on overall structural positioning, than electronics, or even optics.

Cheers

[planters]

However your cooler, has been designed for a certain common type of computer structure, (therefore allowing it to be cheap), and as I pointed out earlier, this makes it a bitch to fit into a projector.... in fact you probably will have to design the projector to fit the cooling system instead of the other way around.

This isn't as silly as it sounds since efficient cooling, is much more dependent on overall structural positioning, than electronics, or even optics.

This is at the root of why many of us build our projectors rather than buy a finished, run of the mill projector. If you explore these opportunities for better cooling, over driving and optical enhancement, you may spend as much or more than you would if you bought some cheep Chinese projector.

More than half the fun (for me anyway) is the thinking about, the designing and experimenting with these systems that allow you to extend beyond the current state of the art. It is similar to building your own high performance gaming comp or hot rodding a muscle car.

You might want to find the best, least expensive liquid cooling system and design the optical layout around this allowing for whatever beam manipulation you would want, provide room for the power system such as power supplies and drivers and lastly...get the lasers.

[dkumpula]

I fully agree, Planters. I couldn't begin to build a rig as exotic as yours, but each of the ~13 builds I have completed to date is something unique and not swapable with anything sold by any professional at any price. I truly enjoy building and then playing with the fruits of my labor.

David