So..  I've been meaning to give an update that shows a little history and some of my failures and what I did to get past them so far...  I'm still working on that.. :)  

I'm doing this update to show a bit to round the edges on what I have been doing...in the past few days..

As the previous couple posts show, I've been working on getting serial communications going.. I think I'm pretty satisfied with what I have..  It pretty much worked from the start, and there doesn't seem to be any packet loss....It could use some better handshaking and error correction, but that will come in time..

So, currently.. I just got everything running from the mini-itx power supply.. the power supply plugs into a mini-itx connector on the power controlBoard and it passes the 5v to the controlBoard, interfaceBoard, and the raspberryPi, etc..  I'll put some pictures up as possible.. 

In the meantime, here's a couple pictures of the laser emitter and power supply.. with the emitter seated into it's nice little case/mount...

A view with the bottom half of the case removed....

And a rear view showing the cooling fan...

Here is a couple pictures of the mirror mount that bolts to the face of the laser emitter...

Bottom half with mirror in place and simulated beam path...

The whole unit.. The printing supports have not been removed in this picture... but it doesn't look a whole lot different after they are removed.

Here is a photo of some of the optics... The important parts...the 522nm Short Pass filter and the 550nm Long Pass filter..  I'll post a photo of the actual filters soon.. I didn't have the gloves, etc. ready to remove them safely..  The other on the left is the surface mirror..which is in the image above...These all came from eBay.

The transmission graph for the 522nm Short Pass Filter..

The transmission graph for the 550nm Long Pass Filter..

And a quick photo of all of the boards in the case hooked up..  

So far....I have all of the boards (raspi, controlBoard, powerControlBoard, and interfaceBoard) running from the mini-ITX power supply... the raspi is running some test python code that cycles through a loop and sends commands to the controlBoard to move the cuvette tray back and forth, select the filter both with the stepper motors... It then cycles the cuvette and laser peltiers using the HBridge.. First it cools one side of the cuvette peltier, then heats it... and then it cools the ccd peltier...then repeats the whole thing.. Works great!  

I'm quite happy that the HBridge controlled peltiers worked out so well.. It proves to me that I will be able to maintain the temperature of the cuvette using a PID controller and PWM and the DS18B20 sensors.. All the code is up on gitHub!