This part is a kind of semiconductor called D2525P40.

Function of this product has Wavelength-Selected D2525P Isolated DFB Laser Module with PMF.

Manufacturers : Agere Systems

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Data Sheet March 2000 Wavelength-Selected D2525P Isolated DFB Laser Module with PMF Applications s Telecommunications — SONET/SDH OC-48/STM-16, OC-192/STM-64 — Extended and ultralong reach — Undersea systems — Dense WDM systems Digital video s Description The D2525P family of DFB laser modules is designed to be used with a lithium niobate external modulator (see Table 4). The laser module features a polarization-maintaining fiber (PMF) pigtail, enabling it to be directly connected to a modulator without the need of a polarization controller. The PMF maintains the polarization of the output light to a consistent orientation. This allows the D2525P to be used as a CW light source for systems requiring extremely low chirp such as undersea or 10 Gbits/s systems. The module contain [ ... ]

D2525P40 PDF Datasheet Download