Posted on February 13, 2017 - ( views)
Lock-in amplifiers were invented in the 1930’s and commercialized in the mid 20th century as electrical instruments capable of extracting signal amplitudes and phases in extremely noisy environments. They employ a homodyne detection scheme and
low-pass filtering to measure a signal’s amplitude and phase relative to a periodic reference.
A lock-in measurement extracts signals in a defined frequency band around the reference frequency, efficiently rejecting all other frequency components. The best instruments on the market today have a dynamic reserve of 120 dB , which means they are capable of accurately measuring a signal in the presence of noise up to a million times higher in amplitude than the signal of interest. This document provides a quick introduction to the principles of lock-in amplification and explains the most important measurement settings. The lock-in detection technique is described both in the time and in the frequency domain. Moreover, details are laid out on how signal modulation can be exploited in order to improve on signal-to-noise ratio (SNR) while keeping acquisition time low. Finally, recent innovations are discussed and the state of the art is described.
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Optimized for testing discrete components, dielectrics, solar cell and semiconductors, as well as bioimpedance monitoring and microfluidic applications
It provides a comprehensive solution for pulsed measurement protocols, by integrating signal generation and detection into a single box
Available in two versions covering the frequency range DC to 500 kHz and DC to 5 MHz (an upgrade from 500 kHz to 5 MHz is possible later).
With an integrated data and web server
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