@inproceedings{oai:jaxa.repo.nii.ac.jp:00008157,
 author = {今仁, 和武 and Imani, Kazutake},
 book = {第22回宇宙エネルギーシンポジウム　平成14年度, The 22nd ISAS Space Energy Symposium March 12, 2003},
 month = {May},
 note = {In order to drive space probes at high speed around solar system, interstellar region and the nearby stars, photon driven sails have been studied to develop solar light sail, laser and microwave sails. The sail acceleration a, which speed is to be near light speed at high temperature, is a function of the temperature T(K), area mass M(kg/sq m) and optical properties (emittance epsilon, reflectance rho and absorptance alpha), namely, a = 2.27 x 10(exp -15) epsilon(rho + 1)/alpha T(exp 4)/M. The temperature of solar sail, which is driven by concentrated solar beam from three reflectors at the Earth or Lagrange point, becomes approximately 180 C, and aluminum alloy reflector can be used. The temperature of laser sail driven by the laser beam on the rear surface of the moon becomes over 1,000 C, and the relatively smaller sail of deep space probes should be made of carbon fiber which is ion-plated by platinum. Nagaura Laboratory developed a new manufacturing process of quartz resonators featuring to make two-steps concave parts on the surface of the piezoelectric blank by using the conventional chemical etching method as the first step and making thinner typically 7 micrometers on another surface of the blank by the reactive ion etching as the second step. The typical reactance-frequency diagram of AE cut is measured that the primary resonance is approximated 212 MHz with the negligible spurious peaks. As the fundamental frequency is inversely proportional to the quartz thickness, thinner device as 1.5 micrometer will resonate near 1 GHz. The solar energy can be converted to electricity by thermal cycle generator or photovoltaic cell. The current solar cell array will be available for microwave beam tube transmitter with stacks of Magnetrons and TWT amplifiers in high conversion efficiency over 50 percent. For a required power density on axis of I, with transmitter diameter d, transmitter power P, microwave wavelength lambda, a maximum usable range of x is obtained to be x = 0.46 d/lambda times the square root of p/I. As the practical frequency for microwave devices is about 10 GHz (0.03 m), the beam intensity of 10 kW/sq m will be got by 1 km antenna with 1 GW transmitter at 5,000 km. When the microwave beam can be concentrated, the sail acceleration is approximately 1 gee, and the space probe will approach light speed in one year., 資料番号: AA0045915007},
 pages = {31--35},
 publisher = {宇宙科学研究所, The Institute of Space and Astronautical Science (ISAS)},
 title = {太陽発電とGHz級振動子によるマイクロ波セイル},
 year = {2003}
}