Berkeley Nucleonics' Model 645 ARB function generator is used with an atomic force microscope (AFM) to determine the properties of materials.
An AFM can resolve distances in factions of a nanometre and map surfaces on an atomic scale.
In addition, it can measure nanoscale contacts as well as measure forces in liquids and molecules.
An AFM consists of a probe mounted on a cantilever with a laser and a photodetector to measure the probe's deflection.
The probe deflection is measured by a laser.
The laser beam is reflected from the probe and the light is converted into an electrical signal by the photodiode.
The user can get an image of a surface by moving the probe across the examined surface and measuring the deflection of the cantilever at each location.
This is usually done with the probe tip in contact with the surface.
An AFM is also operated in a non-contact mode, where frequency and amplitude modulation are common.
Often, users look at changes in oscillation frequency or phase of oscillation when operating in a non-contact mode.
In this particular application, BNC's Model 645 ARB function generator is used with the AFM's Z-Piezo to indent materials and to subsequently measure the materials' mechanical properties.
Piezoelectric material expands and contracts when a voltage is applied.
In this application, the material is biological and the swept frequency helps to determine the material's frequency response.
AFM applications monitor oscillation frequency, amplitude and phase to give more information.