Arduino Laser Controller updated to v2!

I had a little bit of free time, so the time came to revisit an old project, the thorlabs-ldc-arduino. [panel] [GUI]. The plan is to include a second Thorlabs Laser Driver, the LDC500.

Laboratory upgrades

We bought a OSRAM 450nm laser diode from ebay, and installed it into a TCLDM9 head paired with an LDC500 driver. The old problem came up, that the laser driver is super, but it cannot communicate with the PC. I grabbed these images from the internet, to describe the problem:

Only two BNC connectors, one for setting laser current, the other is for checking the laser current.

Panel upgrades

The custom shield had to be updated:

  1. A BNC splitter is used to duplicate the MOD In.
  2. A new BNC connector is added (ADC-CTL OUT)

Code upgrades

The arduino and labview code can be found on github.

Arduino Changes:

  • Merged the the DHT branch with the master branch: I marked the parts which need to be commented out in case there is no DHT22 sensor an library.
  • Updated the code to include a second laser in read only mode. The read commands are incremented by one letter: [j? q? qa?]
  • Adjusted the linear coefficients to work better with two lasers.

Labview GUI Changes:

  • Labview 2014 version (no changes here).
  • Stripped the previous code from the Cobolt subVIs.
  • Introduced an initial delay, because there has to be a wait after the arduino is reset.
  • Replaced the setPower actuator to a setCurrent actuator.
  • Shortened some delays.

Known limitations

As the LDC500 does not have an ON/OFF input, when both controllers are turned on, both of them ar controlled at the same time (BNC slpitter). To overcome this, the user can switch off the LDC205 controller with the ON/OFF button on the GUI and control only the LDC500 driver. Or the user can turn off the LDC500 controller with the power button on the driver and it won’t interfere with the reactivation.

Note: We don’t use the two lasers at the same time, so for us it is not a problem.


Stepper Motor Controller a la Arduino

This is a relatively easy recipe, for beginners. The idea behind the project was that there was a need for fine stage control in the laboratory and a Thorlabs motorized actuator (like the old ZST25 or the newer ZST225B) + controller can be quite expensive. So I made my own Harder, Better, Faster, Stronger version.

Continue reading “Stepper Motor Controller a la Arduino”

Arduino controller for Thorlabs LDC200C Series

As my daily job is being a physics PhD student at the Advanced Optical Imaging Group, some good spin-off projects appear which can be released into the open source wilderness. The story starts with a 405nm diode laser, which we installed into a Thorlabs LDC205. The problem with this super controller that there is no RS232 or USB connectivity. Just 3 BNC connectors (1,2,3). As we want to computerize our dSTORM controls, the LDC has to be pimped…Current_Controller_A2-780 Continue reading “Arduino controller for Thorlabs LDC200C Series”