Characterization Machine Documentation
18 Channel Devices
These devices are becoming well understood and are relatively straight forward. If this is your first testing experience, start here.
Previous Work
The steps to get the device to the testing stage are as follows:
Wiki Page Created
Polishing
Device Pictures Taken
Metricon Reading Completed
Wire Bonded
Impedance Matching Completed
Prism coupling
Choose the appropriate mounting stage and attach the mounting bracket to the characterization machine.
Center the device on the mount and lower the mounting screws to hold the device in place.
Choose the correct prism (TE for X cut devices, TM for Y cut devices)
Clean both the prism and the sample
Dry mount the prism to the sample applying pressure until finger tight. (DO NOT Over Tighten as you will break the sample or prism.)
Check for the rainbow reflection under white light of the wet spot.
Place the mount in the characterization machine.
18 Channel Device Parameters
These are just close approximations you will always need to fine tune.
| | Red | Green | Blue |
| Laser Voltage | 5V | 5.5V | 6.5V |
| Angular Reading | 354° | 357° | 5° |
| Center Frequency | 450 MHz | 480 MHz | 550 MHz |
Alignment
Now that you have mounted the device you are ready to align the machine. Using the table in the section before do the following:
Connect the RF cable to the Transducer you wish to test.

Power on the Laser to the appropriate voltage.
Check the polarization (adjust for least light transmitted through a horizontal polarizor).
With the adjustable aperture all the way open rotate the sample and position it to the correct angular reading.
Adjust the XY stage and rotation stage until waveguiding in the desired mode is achieved. It should look like the picture on the right.
Set RF generator to the correct center frequency. (Verify that is is outputting a signal and that the amplifier is on)
Move the platform vertically until you see deflected light.
Manually scroll through frequencies to verify that the light truly is deflected light.
Close the aperture and fine tune your adjustments.
Take a picture of the coupled light in the sample and a short video of the sweep of deflected light.
Automatic Testing
Now that you have a working device it is time to collect some data. Do the following:
Verify the polarizor on the power wand is properly oriented.
Place the power wand so that it is aligned with the edge of the device and centered vertically.
Rotate the linear actuator until the marker reads 90. degrees.
Record the “Sample Number”, “Transducer”, “Mode”, “Laser Voltage”, “ “Wand Offset from Zero”, “Distance to Detector”, “Wand Angle Reading”, and any notes in the Labview program.
Set the test parameters in the correct fields.
Close the Black Box.
Make sure the “Output to File” button is pushed.
Hit Run
Good results look like this:
Once you have finished testing all colors and modes run it through the Matlab code to compare results.
Congratulations! You're done.