Optical miniature rotary encoders working with diffractive encoder disk made of plastic
Encoders – also referred to as rotary encoders – detect the angular position in rotational movements and are used in a broad spectrum of applications in areas such as automation, robotics, and equipment manufacturing
Our approach uses a diffractive encoder disk made of plastic instead of an encoder disk made of glass. In this case, the signals are read out by a compact optics module in a reflective arrangement. This allows this functional principle to be perfectly implemented for miniature encoders.
State-of-the-art, high-resolution optical rotary encoders generally use cost-intensive encoding disks made of glass, and require complex adjustment at installation. In contrast, through the suitable design of illuminating or readout optics, our rotary encoder can be installed without complex adjustment. The innovative rotary encoder concept enables development of incremental, as well as absolute coded systems. For the production of the encoder disk, we rely on the manufacturing processes of CD production; optical phase lattice structures in the sub-micrometer range are produced on the measuring element.
Our know-how lies in the development and design of customer-specific applications for which no standard solutions are available. This allows tasks such as implementing extremely miniaturized optical encoders of only a few millimeters in diameter and also hollow shaft encoders. Starting with the idea and design of the coding and the optical path, the optical elements, such as lenses, diaphragms, diffractive elements, etc., are also manufactured in house. Laser diodes, LEDs, photo diodes, and chips for the signal processing are selected according to the requirements and procured for mounting the optics modules. The subsequent characterization and calibration of the optics modules or encoders also belongs to the service spectrum.