LUNA’s Log Detector is a useful photodiode amplifier designed to measure low light levels, down to -85 dBm and produce linear logarithmic electrical signal. It come with two or four channel options. The LPD 100 is particularly suited to perform high dynamic range power measurements in closed loop related applications.
Figure 1 : LPD 100 (-90 dB) Log Detector
For example, in polarization tracking, specifically when trying to track to a minimum light level, where generating a reliable tracker feedback signal could be a challenging problem. High Dynamic Range Power Measurements in Closed Loop-Related Applications Luna designed the LPD-100 by utilizing a newer log amp design with a large dynamic range and fast response. Below is an example of the new LPD-100 Logarithmic Detector detecting over 10 decades of optical power from four or two analog outputs.
Figure 2 : High Dynamic Range Power Measurements in Closed Loop-Related Applications
KEY FEATURES :
• Calibrated from < -85 dBm to >10 dBm
• Response up to 4 MHz
• Single buffered analog (SMA) voltage output
• Compact size
• Modular design
APPLICATIONS :
• TE/TM Polarization Alignment
• PIC Testing
• Polarization Tracking