  In this paper a new method for spotsize-measurement for singlemode optical
components is presented. Based from the classical farfield-method where the
measurements are made circular, the mounting of the used rotary stages and the
long measurement time are great disadvantages. In this paper a new planar
method is described which overcomes these problems. Based on the measurement of
a singlemode fiber in accordance with ITU Recommendation G.652 the efficiency
is demonstrated and discussed.
