THORLABS LEDD3 Series, Руководство по эксплуатации

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15 Operating the LEDD3
© 2009 Thorlabs
3.1.2
Operation Modes
Only if one of the three operation modes (Constant Current, Internal Modulation or
External Control) is selected the LED can be enabled /switched on.
It is possible to leave the active mode when the LED is switched on and enter the
main menu. However, the LED has to switch off before you can enter another
operation mode. This can be done while the main menu is selected by pressing the
LED button.
Constant Current Mode
The 'Constant Current Mode' provides a constant non-modulated LED current. The
current can be set directly with the multi-control knob. No confirmation is necessary.
The 'Ok' button has no functionality within this mode. The LED is switched on or off
with the LED button. The LED current can be changed when the LED is off as well as
when it is in operation. This allows to increase or reduce the brightness of the LED.
The current limit is displayed at the bottom of the screen.
Return to the main menu with the 'ESC' button.
Figure 6 Constant Current Mode
Internal Modulation Mode
This mode can be used to apply a sine wave modulation to the LED with a defined
frequency.
The 'Internal Modulation Mode' features three settings: current, frequency and
modulation depth. The first parameter is the DC component. The frequency can be
set between 10MHz and 100MHz in steps of 0.1MHz. The modulation depth
describes the relation between constant and variable component.
Figure 7 Internal Modulation Mode
To change the settings select one of the parameters using the multi-control knob and
press the 'Ok' button. The corresponding screen appears and the value for the
current, the frequency or the modulation depth can be adjusted with the multi-control