3.5 Constant power mode (CONST P)
LDC2xx / page 19
By pressing "ON" (L9) switch off the laser current.
Select constant power (CONST P) with "P" (L22).
Set the adjust knob (L10) completely to the left.
Switch on the output by pressi ng "ON" (L9). The LED "ON" (L8) lights up, the output
is activated and the current slowly increas es (about 1 s) to the value set with the
knob (L10).
With the knob (L10) you can cont inuously set the photodiode current "I
PD
" and thus
the optical power of the lase r diode until the laser current "I
LD
" reaches the selected
current limit "I
LIM
".
If the desired photodiode current "I
PD
" cannot be set exactly enough with the knob
(L10), the range of the knob (L10) can be adapted to the provided photodiode current
in wide ranges with the potentiometer "PD RANGE" (L24).
If no photodiode is connected or the polarity of the photodiod e is set wrong (refer to
chapter 3.3), the laser current "I
LD
" increases to the set current limit "I
LIM
" after the
output is switched on.
If the photodiode current "I
PD
" is interrupted in constant power mode, the laser
current "I
LD
" increases to the set current limit "I
LIM
".
If the injection current "I
LD
" is limited by the se lected current limit "I
LIM
" ripple and
noise do no longer correspond to the specific ations for normal operation. However,
the set maximum current "I
LIM
" cannot be exceeded.
If the connection to the laser diode is in
terrupted during operat ion the output is
switched off automatically. LED "ON" (L8) extinguishes , LED "OPEN" (L6) lights up
and a short beep is heard as warning.
If the output is switched on wh ile the interlock is closed and there is no laser diode
connected, at first the LED "ON" (L8)
lights up and the output is switched on.
Immediately afterwards the LDC2xx rec ognizes the missing of the laser diode,
switches the output off, the LED "ON" ( L8) extinguishes and the LED "OPEN" (L6)
lights up.
