Abstract: A system and method indicate capability for detecting methane leaks inside buildings. This approach provides the ability to detect methane behind high efficiency coated windows and can extract methane concentration (rather than concentration-path length product CL). Lock-in imaging technologies can facilitate lower laser transmitter power. A field deployable, hand held prototype sensor for use in remote sensing a appropriate standoff distances can support operational testing. Distance infrared imaging of methane is feasible. Fully characterized real time image of a methane cloud offers operational advantages in accuracy and safety as compared to current sensors.

Abstract: A system and method indicate capability for detecting methane leaks inside buildings. This approach provides the ability to detect methane behind high efficiency coated windows and can extract methane concentration (rather than concentration-path length product CL). Lock-in imaging technologies can facilitate lower laser transmitter power. A field deployable, hand held prototype sensor for use in remote sensing a appropriate standoff distances can support operational testing. Distance infrared imaging of methane is feasible. Fully characterized real time image of a methane cloud offers operational advantages in accuracy and safety as compared to current sensors.

Abstract: A system and method indicate capability for detecting methane leaks inside buildings. This approach provides the ability to detect methane behind high efficiency coated windows and can extract methane concentration (rather than concentration-path length product CL). Lock-in imaging technologies can facilitate lower laser transmitter power. A field deployable, hand held prototype sensor for use in remote sensing a appropriate standoff distances can support operational testing. Distance infrared imaging of methane is feasible. Fully characterized real time image of a methane cloud offers operational advantages in accuracy and safety as compared to current sensors.

Abstract: An open circuit voltage photodetector comprises a photovoltaic device including a photovoltaic junction, and a transistor. The photovoltaic device is connected to the gate terminal of the transistor to input an open circuit voltage of the photovoltaic device to the gate terminal. An array of such photodetectors and a readout integrated circuit forms an image sensor. In a photodetection method, an open circuit voltage is generated in a photovoltaic device in response to illumination by incident radiation, and the open circuit voltage is applied to a gate terminal of a transistor to modulate a channel current flowing in a channel of the transistor. A readout electronic circuit may be fabricated with an extra transistor, and a photovoltaic device disposed on the readout electronic circuit and electrically connected to apply an open circuit voltage of the photovoltaic device to a gate of the extra transistor.

Abstract: An open circuit voltage photodetector comprises a photovoltaic device including a photovoltaic junction, and a transistor. The photovoltaic device is connected to the gate terminal of the transistor to input an open circuit voltage of the photovoltaic device to the gate terminal. An array of such photodetectors and a readout integrated circuit forms an image sensor. In a photodetection method, an open circuit voltage is generated in a photovoltaic device in response to illumination by incident radiation, and the open circuit voltage is applied to a gate terminal of a transistor to modulate a channel current flowing in a channel of the transistor. A readout electronic circuit may be fabricated with an extra transistor, and a photovoltaic device disposed on the readout electronic circuit and electrically connected to apply an open circuit voltage of the photovoltaic device to a gate of the extra transistor.

Abstract: A system and method indicate capability for detecting methane leaks inside buildings. This approach provides the ability to detect methane behind high efficiency coated windows and can extract methane concentration (rather than CL). Lock-in imaging technologies can facilitate lower laser transmitter power. A field deployable, hand held prototype sensor for use in remote sensing a appropriate standoff distances can support operational testing. Distance infrared imaging of methane is feasible.

Abstract: A concentrator photovoltaic solar cell array for terrestrial use for generating electrical power from solar radiation including a central support which is rotatable about its central longitudinal axis, a support frame carried by, and rotatable with respect to, the central support about an axis orthogonal to said central longitudinal axis, and a solar array mounted on the support frame. The solar cell array includes a plurality of Fresnel concentrator lenses and multijunction III-V compound semiconductor solar cells each producing in excess of 10 watts of DC power. An actuator is provided for rotating the central support and the support frame so that the solar cell array is maintained substantially orthogonal to the rays of the sun as the sun traverses the sky.

Abstract: A concentrator photovoltaic solar cell array for terrestrial use for generating electrical power from solar radiation including a central support which is rotatable about its central longitudinal axis, a support frame carried by, and rotatable with respect to, the central support about an axis orthogonal to said central longitudinal axis, and a solar array mounted on the support frame. The solar cell array includes a plurality of Fresnel concentrator lenses and multijunction III-V compound semiconductor solar cells each producing in excess of 10 watts of DC power. An actuator is provided for rotating the central support and the support frame so that the solar cell array is maintained substantially orthogonal to the rays of the sun as the sun traverses the sky.