The infrared monochromatic image of corona was reported in 1975. The Solar Infrared electric field observing and researching was proposed in 1986 and infrared solar magnetic field observing was suggested in 1987. These observing data describes various states of solar atmosphere. To varying degrees, compared with traditional system, near infrared system have its special characteristics.
In this paper, we present a vacuum solar telescope with a near-infrared (at 8438 angstrom ~ 10830 angstrom) filter system which is designed to measure the solar electric field and monochromatic image in Huairou workstation of Beijing Astronomical Observatory (BAO). The vacuum optical telescope will be consist of a primary mirror in 35cm Diameter, a Gregorian mirror, two vacuum windows, a collimating lens and an imagine lens. The filter with polarizing analyzer will be consist of two pre-filters, one liquid crystal analyzers, a universal birefringent filter which spectral range is in 8000 angstrom ~ 11000 angstrom and pass-band 0.25 angstrom at 10830 angstrom. The birefringent filter and the optical system of the telescope are described in details. We expect to achieve an electric field observing system, two-dimensional monochromatic image observational system of corona. It also can be turned across the spectral line to obtain line profiles of two-dimensional of the field.