1. A method for determining an output value of a sensor of automation technology having a non-linear characteristic curve describing a functional relationship between an input variable and an output variable of the sensor, the sensor having a microprocessor for conducting calculations, the method comprising the step of: producing a characteristic curve K pointwise via a point set SP of calibration points P 1 -Pn and an expanded point set SP′ with additional help points H j ; said help points H j are obtained via, in each case, neighboring points of the point set SP P i+1 , P i+2 , P i+3 , P i+4 , these being obtained according to the following calculational specification carried out by the microprocessor: A. determining slopes m 1 , m 2 , m 3 of three line segments g 1 =P i+1 , P i+2 , g 2 =P i+2 P i+3 and g 3 =P i+3 P i+4 ; B. calculating slope mP i+2 =(m 1 +m 2 )/2 of a first help line h 1 ; C. calculating slope mP i+3 =(m 2 +m 3 )/2 of a second help line h 2 ; D. determining intersection S of the two help lines h 1 and h 2 , wherein the two help lines h 1 , h 2 pass through the points P i+2 , P i+3 , respectively; E. taking the intersection S as help point H j in an expanded point set SP′; and ascertaining the value of the output variable from the value of the input variable via an interpolation of at least two points of the expanded point set SP′ of the characteristic curve K.