A new miniaturized absolute gravimeter has recently been developed to aid in the acquisition of absolute gravity for geophysical investigations and survey applications. The new instrument is much smaller than previous absolute gravimeters and can acquire data at a much higher rate. This technology will enable the development of a new generation of land, marine, and airborne absolute gravimeters.
The absolute gravimeter is based upon a direct measurement of the acceleration of a test body in free-fall using a very precise laser interferometer. A small reflective test-body is launched into the air for about 7 cm and tracked using a precise laser over its symmetric rise&fall path of over 200 ms. These individual measurements can be repeated very quickly, at a rate of 2 throws/second.