Santec OTF-930 - Features; Wavelength Range; Peak Search Function; Optical Power Monitor

Optical Tunable Filter OTF-930
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Features
The Peak Search function provides automatic searching and selection of the wavelength with the
greatest optical power. The function operates by sweeping the lter through a specied wavelength
range whilst continuously monitoring the optical power. On completion of the search the filter
automatically moves to the wavelength with greatest optical power. The Peak Search Function has
two modes. In the standard mode the OTF-930 sweeps through the specied wavelength range in
0.001nm steps. A peak is thus selected with high accuracy, and by selecting a suitable scan range the
function can even be used to select a single wavelength from a comb of signals. In addition, a Rapid
Mode can also be programmed. In Rapid Mode an initial course wavelength sweep is performed
at 1nm intervals and this is followed by a ne wavelength sweep in 0.001nm steps over a range of
±1nm from the detected peak. The Rapid Mode thus enables a rapid scan over a broad wavelength
range to be achieved whilst maintaining the high resolution and accuracy.
3.2. Peak Search Function
3.1. Wavelength Range
The OTF-930 can be supplid in a variety of factory preset congrations. Internally,the instrument has
two individual lter elements. These can be seleced to give an 80nm tuning range, or a 40nm tuning
range with two different lter types. The most common congraion is 80nm to cover the C and L
wavelength bands (1530-1570nm) as used in dense wavelength division multiplexed communication
systems.
Optical power monitoring is realized by tapping the optical signal using a coupler behind the lter
element and monitoring this using a photodetector. Compensation for the wavelength sensitivity of
the photodetector is carried out automatically.
3.3. Optical Power Monitor