The Watt Balance: An Experiment to Realize the New Definition of the Kilogram

The Watt balance is comparing mechanical and electrical powers. In a first step, the mechanical force on a test mass in the earth’s gravitational field is balanced with an electro-magnetic force using a current-carrying coil. In a second step, the coil is moved through the magnetic field, which induces a voltage. The precise knowledge of the electrical, gravitational and dynamical properties allows to infer the mass by using natural constants only, which allows to redefine the kilogram - instead of using the prototype mass in Paris. One requirement during the two phases of the experiment is the accurate determination of the position and angular orientation of the coil. This measurement is performed using the PICOSCALE Interferometer.

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PICOSCALE Interferometer Controller

The controller contains the laser, detection electronics and provides all data via several interfaces.

PICOSCALE Breakout Box

The Breakout Box allows convenient access to the versatile digital and analog in- and outputs.

PICOSCALE Environmental Module

Refractive index compensation for measurements in air is easily achieved with the Environmental Module.

PICOSCALE Temperature Box

Accurate measurements of temperatures for real-time compensation of thermal drifts.

Software and Graphical User Interface

The free and very open software eases the use of the PICOSCALE and makes your work very efficient.

PICOSCALE Firmware Modules

Convince yourself of the unique and powerful firmware modules of the PICOSCALE Interferometers
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