Blue frenzy hits the holographer too

[Colin Kaminski]

I have studied what is going on a little today. The other thing that is quite exciting about this as people are buying these projectors new, removing the blue lasers and then have nothing to do with the DLP chip and circuit! I am trying to buy one now. Multiplex here we come!

[wler]

I have studied what is going on a little today. The other thing that is quite exciting about this as people are buying these projectors new, removing the blue lasers and then have nothing to do with the DLP chip and circuit! I am trying to buy one now. Multiplex here we come!

There are people who bought 10 projectors, I guess there would be plenty of unneeded materials around - check in particular the group buys at PL.

This is cazy - engineers spent efforts in designing these projectors, a lot of high tech parts go into manufacturing them, and then they are bought like crazy so that some stores are sold out already, however just for ripping out the diodes. No wonder if single pieces of those cost thousands of $....

I guess that won't go on for long, I can image these projectors being pulled out soon and perhaps others are built from which one cannot easily remove the diodes any more. One reason is that now hundreds of such diodes are in hands of those balloon poppers who built 1W pointers with them, and it is just a matter of time until something serious happens and then this may be heavily regulated.

[DJ Mathson]

Would it still be possible to run the dlp chip without the blue diodes, the LEDs and optics and get a working image to project?

[Jem]

Multiplex here we come!

Hi Colin

Not quite sure what you mean. What can you do with the salvaged parts that has relevance to holography?

Jem

[Colin Kaminski]

You can use the chip to make a real image. If you feed it a series of images that were taken from a moving camera or of a moving object you can record a series of stereograms. The chip is much better than a LCD for projecting the images. In theory, one needs only a computer, the DLP hardware and a way of moving a slit past the film. I have never tried it because I was not willing to pay $3000 for the DLP development system.

[BobH]

I've also heard of problems with the blue light degrading the phosphor some way. Not only are "balloon poppers" buying them to harvest the lasers, Wicked Lasers are doing it to and offering a nearly 1W handheld laser at 445nm on their site for about $200. :naughty:

I have to admit that I bought one because it's such a big step in lasers per se, and I want to show the progression of lasers per se as a commercial (now consumer) product in my collection of them. And what red-blooded laser lover can resist 1W of 445nm blue coming out of a flashlight? :drool: :drool: :drool: :naughty: :naughty: :naughty: :shhh: :shhh: :shhh:

[DJ Mathson]

And what red-blooded laser lover can resist 1W of 445nm blue coming out of a flashlight?

I can´t really understand the excitement over laser pointers. Or, maybe I can, but personally I lost interest after my first 5 mW 655 nm laser pointer. And that one I bought for holographic purposes. Now, big lab style lasers, or gas lasers, that´s another deal...

Though I love that these 445 nm diodes have hit the market and trickled down to the hobbyists, I fear that they will cause trouble and new legislations will follow.

[dave battin]

I have to admit that I bought one because it's such a big step in lasers per se, and I want to show the progression of lasers

Bob was that a diode you bought or casio
projector ?

[BobH]

I'll not use the word "pointer" for a Class 4 handheld laser. That's like using the word "toothpick" to describe a jackhammer. And I agree with you about pointers. But I felt compelled to get one of these consumer products built with harvested lasers. I bought the laser, not the projector. I want to use it to show how far lasers have progressed. I think they'll be restricted or pulled from the market and I wanted one for my collection. I swear I'll not pop a single balloon with it! :naughty: :shhh:

[a_k]

Hello wler,

Thanks a lot for bringing this interesting LD to our attention. It's incredible how quickly this high power and very affordable LD has become available. I look forward to testing them too.

I was very intrigued that single longitudinal mode operation was possible at all with a multi emitter LD. In this type of LDs each emitter usually operates on its own and different frequency if they are not synchronised e.g. with a feedback common to all emitters, as done by Ondax with their VBGs etc. I don't assume that these LDs come with a built in VBG. The only feedback would be from the LDs window (+ from the collimator). I wonder if this non-selective feedback could be sufficient for a synchronous operation of all emitters. The alignment of the window would need to be extremely accurate for this to be possible and i'm not sure this is the case.

I wonder what supports the assumption that this LD is identical with Nichia's NDB7352, which comes in a 9mm can. The characteristics given in Nichia's data sheet show very large ranges of variation, like threshold current between 150mA and 300mA, wavelength between 440nm and 455nm, ratio of beam divergence angles between 1:2 and 1:6, efficiency slope between 0.8A/W - 1.8A/W. This data could fit almost any LD with similar power and in my view is not of much use for the identification of an LD from unknown origin.

It's a pitty the LD did not perform well in your preliminary ECDL test. Let us hope the performance can be improved. I'm looking forward to your further tests, hoping that the capability for single mode operation is typical for this kind of LDs and not an exception.

Thanks a lot for sharing your experiences.

Ahmet