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O P E R A T I O N S
Operating from the Front Panel
24
LDC-3700C Series
C H A P T E R
2
Automatic Shutoff Conditions for Laser Output
The following conditions automatically cause the instrument to disable the current
source output from the instrument:
•
LASER High Power Limit
•
LASER Interlock/Key Lock turned off
•
LASER Open Circuit or Voltage Limit
•
TEC High Temperature Limit Condition
Operating a Laser in Constant Power Mode, P
Suppose you want to operate a 3 mW laser in constant power at 1 mW. The
3700C Series Controller allows you to operate the instrument current source
driver in a Constant Power mode. In this mode, the controller drives current to the
laser to reach a set power value in mW. The control loop feedback parameter is
photodiode current which the controller converts to optical power via a user
defined photodiode responsivity number. If laser power changes due to internal or
environmental conditions, the controller will increase/decrease the current to the
laser to maintain the power set point. The following paragraphs detail the
instrument configuration in Constant Power Mode.
To set the LDC-3700C in Constant Power mode, select
P
in the
LASER MODE
section of the front panel by toggling the
SELECT
push button. Repeatedly
pressing the (
LASER
MODE
)
SELECT
switch cycles through the current (
I
), light
power (
P
), or high bandwidth current (
I
HBW
) control modes. The LED indicator
shows the selected mode.
Entering Photodiode Responsivity values
The photodiode responsivity,
CAL
PD
, is used to convert between photodiode
current and optical power of the laser diode. To enter the
CAL
PD
parameter,
select
CAL
PD
with the
SELECT
push button by toggling down past
LIM
P.
The
indicator becomes lit when
CAL
PD
is selected and the display indicates the
responsivity parameter in
A/mW (not annunciated). Rotate the adjust knob in the
ADJUST
section while holding the
(PARAMETER) SET
push button to enter a
ON
OUTPUT
I
HBW
P
I
SELECT
LASER MODE
Содержание LDC-3700C Series
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Страница 8: ...L I S T O F FIG U R E S vi LDC 3700C Series...
Страница 10: ...L I S T O F TA B L E S viii LDC 3700C Series...
Страница 78: ...RE M O T E O PE R A T I ON Command Syntax 62 LDC 3700C Series C H A P T E R 3...
Страница 150: ...C O M M A N D RE F E R E N C E Command Reference 134 LDC 3700C Series C H A P T E R 4...
Страница 176: ...C A L IB R A TI O N A N D TR OU BL E S HO O T IN G Troubleshooting 160 LDC 3700C Series C H A P T E R 5...