Heather Panic -- Slice scope 1

Rotation 1 Report November 8, 2010

Heather Panic

During the first rotation period I worked on two projects in the Van Hooser lab.

Project 1: Optics and illumination for a new fluorescence microscope rig

The first project was to build a prototype of the illumination and optics system for a new fluorescence microscope. The microscope will use a combination of LED illumination and an ultraviolet laser, and Prof. Van Hooser explained to me how optical glass could be used to combine the beams from the various light sources into a single light source.

I looked up the excitation and emission spectra for the fluorophores that the Van Hooser lab expects to use. Using this information, I selected the LED lights that were closest to the excitation spectra of the fluorophores, excitation filters to further narrow the LED light spectra, and emission filters to select the wavelengths emitted from the fluorophores. I also selected dichroic mirrors to combine the beams of the LEDs, to direct the illumination towards the sample, and to direct the light from the sample towards the camera.

After the LEDs, optic glass, and optic 'cage' mounting parts arrived, I assembled and tested the LED illumination.

Project 2: Galvo mirrors

The beam of the ultraviolet laser for the microscope will be steered with a 2 axis galvo mirror system. I removed the galvo motors from their original mount and assembled them into a cage mount so that they could be aligned with the other optics.

The galvo motors should be controlled from a computer. I installed a National Instruments input/output board in a server computer and hooked the board up to a BNC connector box. I created a Matlab program to move the motors, although I was only successful in moving a single motor at a time.

Other activities

During this rotation period, I also had the opportunity to observe some lab techniques, thanks to members of the Katz and Turrigiano labs. They allowed me to watch a perfusion, the creation of slices, and a cell patching procedure.

Email thread with Thor labs:

From: heather panic <heather.panic@gmail.com>

Date: Mon, Nov 8, 2010 at 4:01 PM

Subject: Re: Problem with Galvo Mirrors

To: Tech Support <TechSupport@thorlabs.com>

Hi there,

When I use NI MAX I can control one of the two mirrors at a time with no problem. I do not see a way to use MAX to move them both at the same time.

I can also use an oscilloscope and the Matlab code to see that the output of the from the DAQ card is correct for both outputs.

The only problem is that when I hook up both mirrors and use the Matlab code then only one mirror works. Is it possible that there is some grounding issue?

Thanks

Heather Panic

On Mon, Nov 8, 2010 at 3:56 PM, Tech Support <TechSupport@thorlabs.com> wrote:

Hello Heather,

I don’t have the DAQ card you have here, but your MATLAB code looks alright to me without test the real hardware. Can you try using the NI MAX(Measurement and Automation software) to output analog voltages to control both of the mirrors and see what happens? If the you can control the mirrors by using MAX, then the mirrors and the DAQ card are both fine. If not, you may want to examine both your code again and try another DAQ card.

In any case, Thorlabs’ Galvo mirror seems fine since the Galvo mirror only needs two analog voltage inputs and the two control channels are independent.

Wei Wang, PhD

Tech Support

Thorlabs

435 Route 206

Newton, NJ 07860

Email: wwang@thorlabs.com

Phone: (973) 300 3000

From: heather panic [mailto:heather.panic@gmail.com]

Sent: Friday, November 05, 2010 5:02 PM

To: Tech Support

Subject: Re: Problem with Galvo Mirrors

Hello,

Thanks for your reply. I'm attaching the matlab code that I was using. We have a NI M series 6259 daq board.

Best,

Heather Panic

On Fri, Nov 5, 2010 at 2:43 PM, Tech Support <TechSupport@thorlabs.com> wrote:

Hello Heather,

The Galvo mirror system is mostly likely fine. The problem may be related to your programing. How did you push the data and trigger? What kind of NI DAQ are you using? Would you mind sharing your code so I can take a look?

Best,

Wei Wang, PhD

Tech Support

Thorlabs

435 Route 206

Newton, NJ 07860

Email: wwang@thorlabs.com

Phone: (973) 300 3000

From: heather panic [mailto:heather.panic@gmail.com]

Sent: Friday, November 05, 2010 10:17 AM

To: Tech Support

Subject: Problem with Galvo Mirrors

Good morning,

I work at the Van Hooser lab at Brandeis University. We recently bought a 2D galvo mirror system from Thorlabs and I am having difficulties driving the two mirrors.

We have a PC running Matlab, that sends control voltages out through a National Instruments output board. I have checked the output signals at this stage, and I can see that there are two correct output signals, each one a sine wave of +10 to -10 V.

When I hook up the signal to the mirror driver boards, however, only one of the mirrors moves. I can swap the cables and the other mirror will then move, so both of the driver boards and the galvo motors themselves work fine. The problem is just that they will not both work at once. Is there some issue related to grounding that I am not taking into account?

Best regards,

Heather Panic