タイトル | Two-Photon-Absorption Scheme for Optical Beam Tracking |
本文(外部サイト) | http://hdl.handle.net/2060/20110003007 |
著者(英) | Ortiz, Gerardo G.; Farr, William H. |
著者所属(英) | California Inst. of Tech. |
発行日 | 2011-01-01 |
言語 | eng |
内容記述 | A new optical beam tracking approach for free-space optical communication links using two-photon absorption (TPA) in a high-bandgap detector material was demonstrated. This tracking scheme is part of the canonical architecture described in the preceding article. TPA is used to track a long-wavelength transmit laser while direct absorption on the same sensor simultaneously tracks a shorter-wavelength beacon. The TPA responsivity was measured for silicon using a PIN photodiode at a laser beacon wavelength of 1,550 nm. As expected, the responsivity shows a linear dependence with incident power level. The responsivity slope is 4.5 x 10(exp -7) A/W2. Also, optical beam spots from the 1,550-nm laser beacon were characterized on commercial charge coupled device (CCD) and complementary metal-oxide semiconductor (CMOS) imagers with as little as 13.7 microWatts of optical power (see figure). This new tracker technology offers an innovative solution to reduce system complexity, improve transmit/receive isolation, improve optical efficiency, improve signal-to-noise ratio (SNR), and reduce cost for free-space optical communications transceivers. |
NASA分類 | Man/System Technology and Life Support |
レポートNO | NPO-46063 |
権利 | Copyright, Distribution as joint owner in the copyright |
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