The setup for our data taking is rather complicated, because we use so many components. 

bulletA main apparatus is the spectrometer.  A driver that allows us to set a starting wavelength and a scan range controls it.  We are also able to choose a speed for the scan, but the spectrometer cannot scan much faster than 250 angstroms/minute. 
bulletThe other main component is of course the laser that we send into the spectrometer.  It is a diode laser and comes with two controls: a temperature dial and a current dial.  The temperature of the diode should stay between 10° and 30° Celsius.  Even then, we must take care not to stay on the higher temperature for long so that we do not fry the laser.
bulletThe output of the laser is controlled by varying the current and the temperature of the diode.  The devices used to accomplish this was an ILX Lightwave LDT-5412 Temperature controller and a Melles Griot Diode Laser Driver Series 200. 
bulletWe focus the laser into the diode by diffusing it with a board wipe (very crude, but effective) and sending it through two lenses.  The light then hits the very sensitive and expensive photomultiplier tube. 
bulletWe watch the picoammeter with great care to make sure the light going into the photomultiplier tube isn’t too intense.  If too much should go in, the tube could be ruined forever.
bulletWe monitor all of this through a Pasco interface, a data-taking device tied to the computer.  We put two channels into the device: one that takes the voltage reading and the other to tell us when the readings start and stop.
bulletThe power meter is used in measuring the power vs. current.
bulletNot included in the picture (for a good reason) is a fiber optic line that we tried using to measure wavelength vs. temperature.  Unfortunately we were not able to get enough light through the line.

 

 

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