I N S T A L L A T I O N A N D O P E R A T I O N
Front Panel Controls
01_10
OMM-6810B
15
C H A P T E R
2
Zeroing
The 6810B and Optical Measurement Head should always be zeroed. Best
results are obtained in a dark environment, especially when power levels are low.
The procedure for zeroing the instrument is described below.
•
The beam from the optical source should be blocked at the source or turned off.
Note:
If a beam stop is used, it should be positioned as close to the source as possible to
allow the maximum collection of background "noise". If the entry aperture to the ILX
Optical Measurement Head is blocked instead, the zeroing function will not work properly.
This is especially true for low power applications or in areas of high background light.
•
If the LED above the DISPLAY ZERO button is illuminated, press the ZERO button once to
disable the existing compensation factors.
•
Press the DISPLAY ZERO button. While zeroing, the "0" digit walks across both displays
and the zero indicator flashes. When zeroing is complete the ZERO indicator is
illuminated. The process takes about 15 seconds.
•
Allow the optical source to enter the aperture of the head. Accurate power and/or
wavelength measurements should be displayed.
Note:
If the ambient environmental conditions change, e.g. the room lights are turned on or
off, the 6810B must be re-zeroed to maintain its accuracy.
•
Pressing the DISPLAY ZERO button again disables the compensating factors and the
ZERO indicator is turned off.
Power Display Units
The ZERO function is used to remove the effects that
ambient light has on the power and/or wavelength
measurement. Pressing the DISPLAY ZERO button when
the LED above the DISPLAY ZERO button is not on starts
the zeroing process. While zeroing, the "0" digit walks
across both displays and the LED above the ZERO button
flashes. The LED above the DISPLAY ZERO button
remains on after the zeroing process is completed. Pressing
DISPLAY ZERO when the LED above the button is
illuminated disables the effects of the zero.
The DISPLAY LOG/LIN button toggles the optical power
display between linear units (pW, nW,
W, mW, W) or
logarithmic units (dBm). If the instrument is in power
autoranging mode the power display autoranges the linear
power units and decimal point.