The Wide-Angle Polarimetric Camera (PolCam) is installed on the Korea’s lunar orbiter, Danuri, which launched on August 5, 2022. The mission objectives of PolCam are to construct photometric maps at a wavelength of 336 nm and polarization maps at 461 and 748 nm, with a phase angle range of 0◦–135◦ and a spatial resolution of less than 100 m. PolCam is an imager using the push-broom method and has two cameras, Cam 1 and Cam 2, with a viewing angle of 45◦ to the right and left of the spacecraft’s direction of orbit. We conducted performance tests in a laboratory setting before installing PolCam’s flight model on the spacecraft. We analyzed the CCD’s dark current, flat-field frame, spot size, and light flux. The dark current was obtained during thermal / vacuum test with various temperatures and the flat-field frame data was also obtained with an integrating sphere and tungsten light bulb. We describe the calibration method and results in this study.

Introduction
Wide-Angle Polarimetric Camera
    Requirements and Specifications
    Concept of Operation
Calibration Test and Result
    Dark Current
    Flat-Field Frame
    Light Flux Estimation
    Focus Adjustment
Summary
Acknowledgments
References

• Sungsoo S. Kim(Humanitas College, Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea, Department of Astronomy and Space Science, Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea) Corresponding author
• Chae Kyung Sim(Exploration Science Project Group, Korea Astronomy and Space Science Institute, Daejeon 34055, Republic of Korea)
• Dukhang Lee(Exploration Science Project Group, Korea Astronomy and Space Science Institute, Daejeon 34055, Republic of Korea)
• Yuriy G. Shkuratov(Astronomical Institute of Kharkiv, V.N. Karazin National University, Kharkiv 61022, Ukraine)
• Gorden Videen(Space Science Institute, 4750 Walnut Street, Suite 205, Boulder CO 80301, United States)
• Vadym Kaydash(Astronomical Institute of Kharkiv, V.N. Karazin National University, Kharkiv 61022, Ukraine)
• Bonju Gu(Satellite Technology Research Center, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea)
• Bongkon Moon(Exploration Science Project Group, Korea Astronomy and Space Science Institute, Daejeon 34055, Republic of Korea)
• Kyung-In Kang(Satellite Technology Research Center, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea)
• Young-Jun Choi(Exploration Science Project Group, Korea Astronomy and Space Science Institute, Daejeon 34055, Republic of Korea, Department of Astronomy and Space Science, University of Science and Technology, Daejeon 34055, Republic of Korea)
• Minsup Jeong(Exploration Science Project Group, Korea Astronomy and Space Science Institute, Daejeon 34055, Republic of Korea)