Neurotechnology Research Systems
© Plexon Inc
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The current is then manually set to 300mA and the light output at the end of the implant is
measured with a light meter. This will compensate for any losses at each optical connection as well
as any variability between LED modules. A similar calibration can be performed for lasers except
that the light output will be converted to a voltage.
If LASER is the output device, selecting Power (mW) as the output mode will bring up Voltage
Output Limit and Light Power fields. You need to manually enter the maximum voltage (usually
5000) and the corresponding power measured at full voltage.
If LED is the output device, the maximum current is determined by the LED Type. The user only
needs to enter the measured light power at full current. If the LED Type is set to Custom, both
Current Output Limit and measured Light Power at the maximum current need to be entered.
As a voltage example for lasers, put 40mW as the power at 5V. Next request 20mW of light in
Manual mode and measure the actual voltage being output on an oscilloscope. You will see that it is
2.5V (5V*20mW/40mW).
7
GUI Function Reference
7.1
Status
The status of a given channel is either Not Ready or Ready. Until a pattern for a channel has been
defined, the status bar will say Not Ready and the start button for that channel will be grayed out.
Digital inputs to that channel will have no effect until the status changes to Ready.
7.2
Output Device
There are two choices in the drop down menu for Output Device:
1. LED
2. LASER
Whenever one of the LED choices is selected, the controller will output a current. Selecting one of
the Laser modes will output a voltage. This voltage is intended to be used to control a laser with an
analog control signal.
7.3
Output Mode
When the output device is set to LED, the output mode can be set to either Current (mA) or Power
(mW). If Power is selected, the power delivered at the Current Output Limit must be manually
entered. Note that when using one of the pre-configured Plexon LED modules, the current limit is
shown next to the wavelength in the LED Type window.
When the output device is set to Laser, the output mode can be either Voltage (mV) or Power (mW).
If Power is selected, the power delivered at the Voltage Output Limit must be entered.