摘要:
A fiber optic probe system includes a fiber optic probe and a carrier cable coupled to the probe. The carrier cable includes an excitation fiber for receiving excitation light and supplying a portion of the excitation light to the fiber optic probe, a return fiber for receiving detected light from the probe, and a directional coupler coupling the excitation fiber with the return fiber. The directional coupler is situated near an end of the carrier cable which is closest to the probe. A plurality of these fiber optic probes can be multiplexed using a plurality of carrier cables, each cable having a respective excitation fiber for receiving excitation light and supplying the excitation light to a respective one of the plurality of fiber optic probes.
摘要:
A sensitive chemiluminescence immunoassay method for field detection of the presence or the amount of low chlorinated biphenyl compounds in a solution is disclosed. The assay has a five minute analysis time and a working range of detection as low as about 1 part per billion chlorinated biphenyl. Kits for the detection of chlorinated biphenyls are disclosed.
摘要:
The end region of a fiber optic sensor is tapered by suspending a fiber in a container. Etchant is added to the container at a controlled rate in order to etch a taper into the fiber. The taper size and shape are controlled by the selection of the size and shape of the container, as well as by the rate of adding etchant to the container.
摘要:
In an embodiment of the invention, an apparatus includes a reticle having a frontside including a pattern to be imaged onto a semiconductor wafer, a thin film located over a backside of the reticle to form a global convex shape and to reduce friction when sliding on a chuck, and the chuck having a topside to which the backside of the reticle conforms.
摘要:
In an embodiment of the invention, an apparatus includes a reticle having a frontside including a pattern to be imaged onto a semiconductor wafer, a thin film located over a backside of the reticle to form a global convex shape and to reduce friction when sliding on a chuck, and the chuck having a topside to which the backside of the reticle conforms.
摘要:
An optical sensor system includes a housing having an open end; first and second windows situated in the housing; a fastener for situating the first window closer to the open end than the second window and permitting an air exchange between a sensing region and the second window; a hermetic seal between the second window and the housing; and an optical sensor situated between the second window and a wall of the housing such that the air exchange does not occur inside the optical sensor. The first and second windows can include materials selected from the group consisting of sapphire, quartz, and glass; the optical sensor to be protected can include silicon carbide; and the sensing region can include a combustion region. If the sensing region includes a combustion region, the first window is situated at a location in the housing sufficiently near enough to the combustion region to vaporize hydrocarbons in the vicinity of the first window, and the second window is situated a location sufficiently far enough from the combustion region so that the hermetic seal remains stable.
摘要:
An optical radiation detector, such as a silicon carbide photodiode ultraviolet radiation detector, is employed for real time, noninvasive monitoring and diagnosis of combustion dynamics in gas turbine engines. The SiC photodiode responds to flame ultraviolet emission, and a Fast Fourier Transform spectrum analyzer peak acoustic frequency components of the detector signal as indicators of systematic gas pressure vibrations related to combustion. The combustion may be modified in accordance with the monitored acoustic frequency components.