  The Solar Optical Telescope (SOT) aboard the Hinode satellite (formerly
called Solar-B) consists of the Optical Telescope Assembly (OTA) and the Focal
Plane Package (FPP). The OTA is a 50 cm diffraction-limited Gregorian
telescope, and the FPP includes the narrow-band (NFI) and wide-band (BFI)
filtergraphs, plus the Stokes spectro-polarimeter (SP). SOT provides
unprecedented high resolution photometric and vector magnetic images of the
photosphere and chromosphere with a very stable point spread function, and is
equipped with an image stabilization system that reduces the error to less than
0.01 arcsec rms. Together with the other two instruments on Hinode (the X-Ray
Telescope (XRT) and EUV Imaging Spectrometer (EIS)), SOT is poised to address
many fundamental questions about solar magneto-hydrodynamics. Note that this is
an overview, and the details of the instrument are presented in a series of
companion papers.
