Differences

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--- d2:laser_controller [2020/12/01 19:30] – Michael Radunsky
+++ d2:laser_controller [2021/06/10 21:20] – external edit 127.0.0.1
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 ==== Description: ====
-The laser controller has two temperature controllers capable of sub-mK stability(( Sub-mK stability requires a proper thermal design and proper tuning of the temperature controller to the thermal plant. If you did not purchase a D2-100 Diode Laser with your Laser Controller, please read the section on tuning the temperature controller.)) and a 200 mA or 500 mA precision current source based on the Libbrecht-Hall(( Libbrecht and Hall, A Low-Noise, High-Speed Current Controller, Rev. Sci. Inst. 64, pp. 2133-2135 (1993).)) circuit.  The laser controller is designed for very fast current modulation via the servo input enabling high-speed servo control of the laser's frequency.  The current servo input can accommodate input frequencies over 10 MHz and is limited by  the 1 kΩ input impedance. Additionally, an RF port is available for higher frequency modulation.
+The laser controller has two temperature controllers capable of sub-mK stability((Sub-mK stability requires a proper thermal design and proper tuning of the temperature controller to the thermal plant. If you did not purchase a D2-100 Diode Laser with your Laser Controller, please read the section on tuning the temperature controller.)) and a 200 mA or 500 mA precision current source based on the Libbrecht-Hall(( Libbrecht and Hall, A Low-Noise, High-Speed Current Controller, Rev. Sci. Inst. 64, pp. 2133-2135 (1993).)) circuit.  The laser controller is designed for very fast current modulation via the servo input enabling high-speed servo control of the laser's frequency.  The current servo input can accommodate input frequencies over 10 MHz and is limited by  the 1 kΩ input impedance. Additionally, an RF port is available for higher frequency modulation.
 <WRAP center round important 60%>The range of pole settings for the T2 temperature control loop (diode temperature control) for D2-105 Laser Controllers with Serial Number 2675 and higher (Temperature Control Board Serial Number 6987 and higher) have been modified to allow the user to more easily control a low thermal mass laser assembly such as a Photodigm TOSA.  Please use the appropriate instructions in the "Tuning the Temperature Controller" section of this manual for your Laser Controller and laser type.
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 <WRAP center round important 60%>The range of pole settings for the T2 temperature control loop (diode temperature control) for D2-105 Laser Controllers with Serial Number 2675 and higher (Temperature Control Board Serial Number 6987 and higher) have been modified to allow the user to more easily control a low thermal mass laser assembly such as a Photodigm TOSA.  Please use the appropriate instructions below for your Laser Controller.
+If you purchased the -FL option for your D2-105, then the T1 loop has the same available pole settings as the T2 loop of controllers with Serial Number 2675 and higher.
 </WRAP>
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 //NOTE: Depending on the thermal design, nested temperature loops can fight each other, causing oscillations and instability. If you observe this, you will need to reduce the gain and/or increase the time-constants on the slower stage. //
-===Tuning Temperature Loop for Photodigm Mercury Lasers===
+===Tuning Temperature Loop for Photodigm Mercury Lasers if you have an older D2-105===
+If you have a D2-105 with S/N 2674 or lower (PCBs with S/N 6986 and lower), then you may still be able to tune the parameters of the loop to stably control the temperature of the TOSA by following the protocol below:
 If you are using the D2-105 laser controller to drive a Photodigm Mercury laser in a TOSA package, the following may be helpful as a starting point for setting the thermal control loop parameters.((Courtesy of [[http://www.photodigm.com|Photodigm]]))  Refer to <imgref side_adjustb>.