4:45 PM - 5:00 PM
[PPS06-18] The Optical Performances of Multi-Band Camera (Flight Model) onboard SLIM
Keywords:Moon, SLIM, Spectroscopy
Smart Lander for Investigating Moon (SLIM) project aims to demonstrate a “pin-point” landing within a radius of 100 m on the lunar surface. It is planned to launch in FY2022.
SLIM is equipped with one science camera: Multi-Band Camera (MBC). Using MBC, we measure multiband spectra of rocks and soils around the landing site, SHIOLI crater, and determine the mineral composition, especially Mg# (= molar Mg / (Mg + Fe)). The MBC is composed of a Vis-InGaAs imaging sensor, a filter-wheel with 10 band-pass filters, a movable mirror for panning and tilting, and an autofocus system.
To examine the optical performance of the Flight Model of MBC (MBC-FM), the barium sulphate integrating sphere and monochromator at Tsukuba Space Center were used. In the exams using the integrating sphere, a flat light source was introduced from the integrating sphere to the field of view of the MBC, and the sensitivity and linearity data of all pixels against the input light intensity, exposure time, and detector temperature were obtained. The presence of stray light was also investigated. The transmittance spectra of the band-pass filters were measured using a monochromator, CT-25CDZ (Bunkoukeiki Co., Ltd.).
The linearities of all pixels for input light intensity, exposure time, and detector temperature was R2 ≧ 0.99, which is expected to obtain a calibration equation with 0.1 % accuracy. The stray light from outside the field of view was less than 1 %. And the transmittance of all bands was more than 80 %. Based on our results, in the case of observing dark mantle deposits (worst case), it is calculated that the signal-to-noise ratio of all bands is greater than 75 in one shot, and the signal-to-noise ratio of all bands is greater than 100 when integrated.
SLIM is equipped with one science camera: Multi-Band Camera (MBC). Using MBC, we measure multiband spectra of rocks and soils around the landing site, SHIOLI crater, and determine the mineral composition, especially Mg# (= molar Mg / (Mg + Fe)). The MBC is composed of a Vis-InGaAs imaging sensor, a filter-wheel with 10 band-pass filters, a movable mirror for panning and tilting, and an autofocus system.
To examine the optical performance of the Flight Model of MBC (MBC-FM), the barium sulphate integrating sphere and monochromator at Tsukuba Space Center were used. In the exams using the integrating sphere, a flat light source was introduced from the integrating sphere to the field of view of the MBC, and the sensitivity and linearity data of all pixels against the input light intensity, exposure time, and detector temperature were obtained. The presence of stray light was also investigated. The transmittance spectra of the band-pass filters were measured using a monochromator, CT-25CDZ (Bunkoukeiki Co., Ltd.).
The linearities of all pixels for input light intensity, exposure time, and detector temperature was R2 ≧ 0.99, which is expected to obtain a calibration equation with 0.1 % accuracy. The stray light from outside the field of view was less than 1 %. And the transmittance of all bands was more than 80 %. Based on our results, in the case of observing dark mantle deposits (worst case), it is calculated that the signal-to-noise ratio of all bands is greater than 75 in one shot, and the signal-to-noise ratio of all bands is greater than 100 when integrated.