SBIR Phase I: Remotely Operated Vehicles (ROV) Mounted Sensor for Benthic Studies

9860528这项小型企业创新研究第一阶段项目将开发一种叶绿素荧光传感器，用于远程操作车辆(ROV)或拖曳雪橇平台。该传感器将对蓝色激发和红色荧光发射波长处的光束衰减的测量荧光信号进行校正。该传感器包含一个参考通道，用于现场测量这些波长下的总光束衰减系数。该传感器的一个独特功能是一个射频调制的蓝色发光二极管(LED)激励源，与频域检测电子设备相结合。这将允许使用光学测距技术准确地确定光学测量路径长度。测量的光程长度和衰减系数然后提供总的激发和荧光光束衰减。除了能够在大范围的水光学条件下确定校正的荧光强度外，该传感器还将测量叶绿素荧光寿命。这一特征是至关重要的，因为它将解决困扰着简单的叶绿素荧光强度测量用于生物量测定的最根本的问题，即由于体内叶绿素的荧光量子产率高度可变，所以叶绿素荧光强度不能与微藻生物量直接相关。预计将在生物海洋学研究和海洋环境监测的传感器中应用。除海洋应用外，其他潜在市场包括农业、水产养殖、鱼类养殖、植物基因工程、生物反应器的在线过程分析和林业。

9860528 This Small Business Innovation Research (SBIR) Phase I project will develop a chlorophyll fluorescence sensor for deployment on a remote operating vehicle (ROV) or towed sled platform. The sensor will correct the measured fluorescence signal for beam attenuation at the blue excitation and the red fluorescence emission wavelengths. The sensor contains a reference channel to measure in situ the total beam attenuation coefficients at these wavelengths. A unique feature of the sensor is a RF modulated blue light-emitting diode (LED) excitation source, coupled with frequency-domain detection electronics. This will permit accurate determination of the optical measurement pathlength with an optical ranging technique. Measured pathlength and the attenuation coefficients then provide total excitation and fluorescence beam attenuation. In addition to being able to determine the corrected fluorescence intensity over a wide range of water optical conditions, the sensor will measure chlorophyll fluorescence lifetime. This feature is critical because it will solve the most fundamental problem that plagues simple chlorophyll fluorescence intensity measurements for determination of biomass, i.e., that chlorophyll fluorescence intensity cannot be directly correlated to microalgal biomass because the fluorescence quantum yield of chlorophyll in vivo is highly variable. Applications are expected in sensors for biological oceanography research and for marine environmental monitoring. In addition to marine application, other potential markets include agriculture, aquaculture, fish farming, plant genetic engineering, on-line process-analysis in bioreactors, and forestry.