Offset Coefficient Adjustment - Newport LDS1000 User Manual

LDS1000
In the second case, a low-pass digital selection is carried out which reduces
the noise.
The noise reduction evolves like the square root of the number N of avera-
ged samples, which is itself equal to the averaging time to acquisition per-
iod ratio.
The acquisition period is always equal to 0.5 msec (2 kHz).
The duration of the averaging is fixed by the integration constant that can
be parametered INTG.
Refer to the user's manual of the LDS sensor concerned.
4.4

Offset Coefficient Adjustment

The Yofs1, Yofs2, Zofs1 and Zofs2 coefficients are normaly set to zero
value.
When the reflected light is becoming low, because of poor reflectivity or
small mirror aperture, it is necessary to take into account the value of the
electronic offsets of the detector.
The LDS1000 Controller is designed to make this correction very easily, by
introducing offset coefficients into its memory.
The following procedure must be accomplished:
The values of offsets are reached when the instrument does not receive
any light.
In order to get these values, place a black screen in front of the exit
pupil of the instrument.
The requested values are then dispayed by the LDS1000 in the specific
test mode, described in chapter 7.3.
The first line gives Yofs1 and Yofs2.
The second line gives Zofs1 and Zofs2.
Take notes of these values and go to LDS1000 parameter setting, as
explained in chapter 7.4.
Controller for Laser Diode Sensors
=> (F5) =>
9
(F4) => (F2)
EDH0170FE1010 – 09/98