SOFT( So–––lar F––lare T––elescope So_larF_lareT_elescope ) installed at BOAO(Bohyunsan Optical Astronomy Observatory) is purposed for observing solar active regions using four refractors on single mount with a 400"×300" 400"×300" field of view: Two refractors with a diameter of 15cm(f15) are observe the white light and Hα Hα , and the other two refractors with a diameter of 20cm(f8) are observe the magnetic field distribution and Doppler shifts at the solar chromosphere. Three Lyot filters, one of the most important observational instruments, are installed on the optical rails for VMG, LMG, and Hα Hα that possible to very narrow pass band observation under high precision stability of temperature. From the combination of KD*P and quarter wave plate in the Lyot filter possible observe the magnetic fields strength and doppler shifts by using the characteristics of polarization components. In this paper, we introduce the basic characteristics, optical system, and monitor system of the SOFT.

We have analyzed 223 data of the daily sunspot observations during the period of January 1 to December 31 in 1996 and present the daily relative sunspot numbers. During the 1996, the preliminary annual average of the relative sunspot numbers found to be 8.8 based on 3.7 distinct spots in a single group for 0.6 spot groups According to the appearance of 123 spot groups, our analysis shows that the mean life time of spot group is about 5 day and 5.8 hours. The proper conversion factor of the Korea Astronomy Observatory(KAO) derived from a comparison of one thousand one hundred and eighty observational sunspot numbers from 1992 to 1996 with those of international sunspot numbers is determined to be 1.17 instead of 0.97 which is in use.

Data acquisition system mounted on the Solar Flare Telescope at Bohyunsan Optical Astronomy Observatory is briefly described. The system is made up with CCD cameras, an image processor, a PCI-type PC and a SUN workstation. The image processor, MVC 150/40 comprises a variable scan acquisition module, an image manager and a binary correlator computational module. A typical polarization image of a sunspot is presented to demonstrate performance of the system.