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Updated: Jun 26, 2026

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
Development of a switched integrator amplifier for high-accuracy optical measurements
John Mountford1, Geiland Porrovecchio, Marek Smid
1National Physical Laboratory, Hampton Road, Teddington, Middlesex, United Kingdom. john.mountford@npl.co.uk
Abstract:
In the field of low flux optical measurements, the development and use of large area silicon detectors is becoming more frequent. The current/voltage conversion of their photocurrent presents a set of problems for traditional transimpedance amplifiers. The switched integration principle overcomes these limitations. We describe the development of a fully characterized current-voltage amplifier using the switched integrator technique. Two distinct systems have been developed in parallel at the United Kingdom's National Physical Laboratory (NPL) and Czech Metrology Institute (CMI) laboratories. We present the circuit theory and best practice in the design and construction of switched integrators. In conclusion the results achieved and future developments are discussed.
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