• Journal of Astronomy and Space Sciences
• /
• v.18 no.3
• /
• pp.239-248
• /
• 2001

Far-ultraviolet IMaging Spectrograph (FIMS) is the main payload of the first Korean scientific satellite, KAISTSAT-4, which will be launched in 2002. Among the optical parts, parabolic cylinder mirror does not have any heritage from previous astronomical missions, so the manufacturing and testing process itself is a challenging issue. We describe the method of manufacturing and measuring of the off-axis parabolic cylinder mirror and our initial experiments to establish the entire manufacturing process. Using the method, the profile error can meet the specification of $lambda$ per cm which is closely related with the astronomical performances. In case of the surface roughness, temperature controlled pitch polishing reduces $R_{q}$ under 1 nm implying that scattering in the entire spectral range of FIMS is less than 2% of the incident UV light.

• The Bulletin of The Korean Astronomical Society
• /
• v.25 no.2
• /
• pp.75-75
• /
• 2000

• Bulletin of the Korean Space Science Society
• /
• 2000.10a
• /
• pp.75-75
• /
• 2000

No Abstract, See Full Text

• Publications of The Korean Astronomical Society
• /
• v.18 no.1
• /
• pp.87-95
• /
• 2003

FIMS (Far-ultraviolet IMaging Spectrograph) is the main payload of STSAT-1 satellite which was successfully launched on September 27, 2003. The optical system of FIMS consists of two sets of parabolic cylinder mirror, slit, ellipsoidal reflection grating, and baffle system. We designed two types of baffle system for the FIMS: FOV baffle and order baffle. FOV baffle in the mirror house controls the field of view, and the order baffle in the vacuum box blocks the rays reflected rays by different orders.

• Publications of The Korean Astronomical Society
• /
• v.19 no.1
• /
• pp.65-70
• /
• 2004

An imaging spectrograph concept optimized for extended far-ultraviolet emission sources is presented. Although the design was originally developed for FIMS aboard the first Korean science satellite STSAT-l launched on September 27, 2003, no rigorous theoretical background of the spectrograph design has been published. The spectrograph design employs an off-axis parabolic cylinder mirror in front of a slit that guides lights to a diffraction grating. The concave grating provides moderate spatial resolution over a large field of view. This mapping capability is absent in most astronomical instruments but is crucial to the understanding of the nature of a variety of astrophysical phenomena. The aberration theory presented in this paper can be extended to holographic gratings in order to improve the spatial as well as the spectral resolutions.

• Proceedings of the Optical Society of Korea Conference
• /
• 2001.02a
• /
• pp.86-87
• /
• 2001

Far-ultraviolet IMaging Spectrograph(이하 FIMS)는 2002년에 발사 예정인 과학위성 1호의 주 탑재체이며, 은하 주변에 분포한 고온의 가스에서 방출되는 자외선 영역 (short wavelength band ： 900-1150 $\AA$, long wavelength band ： 1335-1750$\AA$)의 방출선을 약 2$\AA$의 분광 분해능으로 관측하는 천문학적 목표를 가지고 있다 일반적인 망원경을 사용하는 대신 제한된 위성의 크기 내에서, 넓은 지역에 퍼져 있는 가스의 분포와 특성을 관측하는데 적합하도록, 그림 1과 같이 비축 포물 원통 반사경과 타원형의 substrate를 가진 회절 에돌이발 (grating)의 사용을 고안하였다. (중략)

• Journal of Astronomy and Space Sciences
• /
• v.17 no.1
• /
• pp.67-76
• /
• 2000

Far-ultraviolet IMaging Spectrograph(FIMS) is the main payload of the first Korean scientific satellite, KAISTSTA-4, which will be launched in 2002. The optical system of FIMS consists of parabolic cylinder mirror, slit, ellipsoidal reflection grating, and MCP to get spatial information as well as spectral information. Allowed ranges of manufacturing and positioning error are derived for each optical components to achieve the astronomical goals. In the procedure, graphical simplification is dedicated to understand sensitivity table and to derive range and precision of manipulation for each optical component. The result shows that precision of ${\mu}m$ for linear and of 2' for angular manipulation fulfills optical requirements.