Butterworth Filters
Refine signal, providing the flattest possible frequency in the passband, with a monotonic response.
See Also: Bessel Filters
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Product
2-Port Optical Tunable Filter
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Optoplex's Tunable Optical Filter, also known as Optical Tunable Filter or Tunable Bandpass Filter, is an integrated module, consisting of micro optics and electronics. When receiving a stream of optical signals of a plurality of wavelengths from the Input-Port (IN), the 2-port tunable optical filter directs a selected channel to the Output-Port (OUT). The selected channel can be varied (tuned) within the operating wavelength (frequency) range by a remote command sent through the built-in control PCB and firmware.
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Product
Gas Filter Correlation CO Analyzer
Model T300U
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Teledyne Advanced Pollution Instrumentation
The Model T300U Trace-level CO analyzer has been developed specifically to address the challenges of low level monitoring as required, for example, in the US NCore network. Using IR absorption with a Gas Filter Correlation Wheel, the T300U is designed to allow ultra-sensitive CO measurements while still meeting the requirements for use as a US EPA compliance analyzer.The optical bench is enclosed in a temperature controlled oven, dramatically decreasing instrument noise and drift. The objective and field mirrors in the sample cell are gold plated to maximize signal to noise performance, while a temperature-controlled Nafion dryer on the inlet minimizes water interference caused by ambient humidity changes. Periodically, the T300U seamlessly corrects its baseline by routing the sample through a heated catalytic CO scrubber. This Auto Reference function corrects zero drift and reduces the effect of interferences.

