To measure the chemical impedance at complex frequencies, a frequency response analyzer, known as the digital version of the lock-in amplifier, is used to make the frequency sweep easier to use.
Tensile tests are to be carried out when evaluating the strength of metallic materials. In order to detect small changes in metal cracks or shape, you can measure the AC resistance of sample (called AC potential method).
The metal detector measures the small change in the sensor's transfer function with a lock-in amplifier.
The corrected DC current of the lock-in amplifier is equal to the DC current flowing through it. The current can be measured by measuring the output of the lock-in amplifier.
Methods for measuring electrons emitted from the surface of a sample include Vacuum Ultraviolet Photoelectron Spectroscopy (UPS), X-ray Photoelectron Spectroscopy (XPS) and so on.
In the laser phase-locked system, the most crucial part is the use of lock-in amplifier to achieve the test gas, reference gas two-way detection, or even to achieve the measured gas, reference gas and laser background three-way detection.
Photo Acoustic Spectroscopy (PAS) is an analytical instrument with a mechanism similar to that of a secondary quantum optical spectrometer.
Spectral measurement system built by a lock-in amplifier and a chopper, only measures the light intensity with a modulated frequency, so as to avoid the influence of other external noise, which can achieve the detection of low light with high precision.
Constant current charging and discharging method, also known as timing potential method. Its basic working principle is to charge and discharge the tested electrode under constant current conditions, record the change rule of its potential with time, and then study the electrode's charging and discharging performance and calculate its actual specific capacity.
In 2017, Jinfeng Jia and Canhua Liu of Shanghai Jiaotong University published an article entitled "Development of in situ two-coil mutual inductance technique in a multifunctional scanning tunneling microscope" article, reporting the development of in situ two-coil mutual inductance technique in a multifunctional scanning tunneling microscope.
