Zantiks MWP units delivered prior to January 2021 had the option of adding a light stimulation stand to act as both a diffusing stand and as an additional bright light source with brightness control. It is useful for optogenetic stimulation, or initiation of a startle response, and comes with an LED light source for a variety of different wavelengths including white, blue, and green (Please contact us to discuss your requirements).
There is a fairly even brightness across the light plate, and we have confirmed that the plate can stimulate zebrafish larvae and adult Drosophila. However, we recommend full validation of stimulation performance in different wells for your test animals.
For assembly instructions please refer to the MWP Introduction manual
Light stand
Here you will find instructions for operation of the light stand for the MWP Z1 units.
We are using a third party LED driver device which allows us to control the on/off and brightness of the LEDs from the ZANTIKS script and electronics. This allows the system to be fully integrated into the Zantiks experiments.
The LED driver is permanently powered from the 3 way connector plugged in as in the previous photo (CN4). CN4 each provides permanent 12V power, a 12V power source switched by relays controlled from Zanscript, and a ground connection. CN4 has power applied by default, and when power is provided here the plate will not be lit. When power is not applied then the LED will light as controlled by the voltage out from the 4th output of CN5. High voltages (10000 mv) keep the stand unlit, and low voltages (anything below about 4000mv) will have the stand at full power.
Script explanation
Below is a download for the demo script opto_stim.zs
Some key points to understand about this script include:
SET(VOLTAGE4, ON)
enables output of voltage on output 4 of CN5.
SET(VOLTAGE_LEVEL,10000)
sets the voltage at 10000mv, which leads to the stand being off. Lowering the voltage to below about 4000mv enables the system to be high power and the light will be at full brightness. Gradually increasing the voltage reduces the LED brightness.
ZCOMMAND("C1#0 P10 C1#1")
ZCOMMAND controls the relay and pauses. "C1#0" turns off the override so that the brightness is controlled by the voltage. "P10" delays (or Pauses) for 10ms. "C1#1" turns the override back on, so the stand is unlit. Increasing or decreasing "P" here will increase or decrease the time the light is on i.e. length of light flash.
The script produces a light sequence of pulses at increasing length, followed by a sequence of varying voltage where the LED changes from maximum brightness down to lights off.
Demonstration of the opt_stim.zs sample script for the light stand
Please note: the light stand can also be operated in the relay output CN3. Unlike CN4, which provides permanent power as a default, resulting in the plate being unlit, the default from CN3 is to provide no power, resulting in the plate being lit.
If you are using the CN3 relay, the above script will work exactly the same, except you will need to edit the ZCOMMAND in the script from "C1" to "C2" in order to control the relay when the connector is in CN3.
Script download
To download the opto_stim demo scripts as .zs files (file type Zantiks software reads), choose the Save File As option in the right-click dialogue box. Clicking on the script name hyperlink will open a read-only version of the script.
Script download: opto_stim.zs
Note: Try running it with the system plugged in to see how control can work for both length of stimulus (e.g., set by P10, P50) and for brightness (by varying the control voltage).
