THORLABS MC2000, Руководство по эксплуатации

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Optical Chopper System
18488-D02 Rev G, September 24, 2012 Page 9 www.thorlabs.com
Part 4. Basic Operation
4.1. Internal Reference Operating Mode
The MC2000 is most often used in the internal reference mode where the chopping speed is set
internally.
1. Turn the MC2000 power on. The LCD display will show the Thorlabs logo and firmware
revision number before changing to the top-level menu list. The display will then show the
current menu, menu options, and operating status of the unit. By turning the front panel control
knob, different menu items can be highlighted. Push the control knob to select the highlighted
item.
2. Set the MC2000 parameters to the following for quick internal operation:
•
Blade – (MC1F10)
•
Ref. In – (INTERNAL)
•
Freq. – Set to the desired frequency
•
Phase – Set to the desired phase
•
Harm N – Set the N harmonic to 1
•
Harm D – Set the D harmonic to 1
3. Highlight and select Run Mode. The unit will adjust its speed and lock onto the set speed within
a few seconds.
Note that all menu parameters can be changed in standby mode, while only frequency, phase and N/D
harmonic parameters can be changed in run mode. The unit always powers up in standby mode.
4.2. External Reference Mode
This mode allows the user to control the chopper blade with a logic-level external reference signal.
1. To enable external reference mode, attach a TTL or CMOS logic level reference signal to the
‘EXT REF INPUT’ BNC on the front panel. Turn the MC2000 power on.
2. Set the MC2000 parameters to the following for quick external operation:
•
Blade – (MC1F10)
•
Ref. In – (EXTERNAL)
•
Freq. – Set to the desired frequency
•
Phase – Set to the desired phase
•
Harm N – Set the N harmonic to 1
•
Harm D – Set the D harmonic to 1