Abstract: The method of measuring positions is based on tracking an interference pattern which is generated when line grids is different line densities are superimposed. According to the present method the line grid of an optical scale is projected onto a line grid formed by a plurality of adjacently arranged diodes, whereby digital switching elements are allocated to the photodiodes and are integrated with same on a common substrate and which compare pair-wise the intensities of adjacent diodes. An absolute measuring of positions proceeds by an additional coding of the line grid of the scale. The method has use in linear as well as curvilinear (angular) measuring of positions.

Abstract: An electronic scale controlling a material feed generates a control signal as the material fed approaches a desired weight. An acoustic tone signal varying in accordance with the control signal and reaching a limiting value when the control signal signifies a zero difference between actual weight and desired weight lets an operator know that desired weight has been achieved.