O P E R A T I O N S
Operating from the Front Panel
26
LDC-3700C Series
C H A P T E R
2
differed from the newly adjusted set point, the
LASER
display will revert to the
original display mode (
I
,
I
PD
, or
P
PD
).
Before the laser output is enabled, the power limit for the laser under test should
be set. In Constant Power mode, this is accomplished by setting a Power limit,
LIM
P
value. The LDC-3700C Controller uses the responsivity value entered to
calculate a power limit. This is a software limit only.
To set the Constant Power limit, use the
SELECT
push button in the
PARAMETER
/
LASER
section to select
LIM
P
. When the
LIM
P
is indicated by the
accompanying LED, the
LASER
display will indicate the limit set point in
mW
.
Press and hold the
SET
push button and rotate the adjust knob clockwise to
increase the limit set point value, or counterclockwise to decrease the limit set
point value. Set the limit to 1.50 mW. When the desired value is reached, release
the
SET
push button to store the new limit value.
The LIM P is the absolute limit of optical power, as detected by the unit via the
monitor PD feedback loop. In order for this limit to be meaningful, the monitor
photodiode responsivity (
CAL
PD
) must be adjusted correctly. This limit is a
software limit only. The LASER output is normally turned off if this limit is reached
(See LASer:ENABle:OUTOFF command in Chapter 4 for instructions on disabling
this function). The maximum
LIM P
value is 100.0 mW (LDC-3714C), 500.0 mW
(LDC-3724C), and 5000 mW (LDC-3744C).
Also, in constant power mode the LASER current limit and voltage limit values are
in effect. Refer to the discussion on page 8 which describes how to set these
limits.
Now the instrument is configured to operate in Constant Power Mode. In the
LASER
MODE
section, enable the output of the laser current source by
depressing the
OUTPUT
push button once. The accompanying led labeled
ON
will illuminate indicating that the laser output is on and current is being driven to
TEC
LAS
ADJUST
TE
LIM I
SAVE
CONST
GAIN
LIM T
HI
TEC
LIM I
CAL PD
LIM I
LIM P
RECALL
SET
SELECT
PARAMETER
LASER
Summary of Contents for LDC-3700C Series
Page 2: ......
Page 8: ...L I S T O F FIG U R E S vi LDC 3700C Series...
Page 10: ...L I S T O F TA B L E S viii LDC 3700C Series...
Page 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...
Page 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...
