Contact-type measuring sensors vs optical sensors

May 13, 2016 Product Notices

Contact-type measuring sensors vs optical sensors

Contact-type measuring sensors, often also referred to as tactile sensors or contact sensors, are ideal for rough industrial environments where the surfaces to be measured are likely to be contaminated by oil, coolants, grease, fat, water, or dust. Optical sensors are not able to measure contaminated surfaces accurately, while contact-type measuring sensor can. However, what may be problematic with contact-type measuring sensors is the mechanical lateral load. The lateral load reduces the lifetime considerably and affects the measuring accuracy. With the new contact-type measuring sensor HG-S, Panasonic launches a solution to this problem that is suited to the industry's needs.

Enhanced mechanical stability

The stability has been enhanced thanks to highly precise plain bearings. The spindle stopper has been designed and positioned in such a way  that the impact on the glass scales is minimized. Another advantage is the fact that glass has a very low coefficient of thermal expansion, which means the resolution will not be affected within the whole range of operating temperature. Conventional contact-type measuring sensors have a typical lifetime of approx. 1 million lateral loads, whereas the HG-S series has a lifetime of 100 million lateral loads, which is one hundred times as long. Thanks to the CMOS technology, measurements are performed with a resolution of 0.1µm and a measurement accuracy of 1µm.

Absolute position detection

Applications in industrial plants tend to focus on productivity and this is why absolute position detection is preferred over incremental position detection. Absolute position detection allows reliable measurements without mechanical zero position runs.


The DIN-rail mountable amplifier has a response time of only 3ms. The 2-line digital display with the integrated graphical indicator are easy to read. One master unit can be connected to up to 15 slave units. The connection allows to copy settings to other units and to collect measuring results. Another bonus is that less wiring is needed.