RG2/RG4 encoder series
Not recommended for new designs
What are RG2 and RG4 ?
RG2 and RG4 are the names given to the range of incremental encoder products that read 20 µm and 40 µm pitch scale types, as detailed in the links below:

Gold plated tape
Scale name | Accuracy | Scale pitch | Coefficient of thermal expansion | Supplied length
| Readhead compatibility |
RGS ![]() | ±15 µm/m | 20 µm/40 µm | Thermally mastered to substrate by use of end clamps | Up to 50 m (>50 m contact Renishaw) |
Glass spar
Scale name | Accuracy | Scale pitch | Coefficient of thermal expansion | Supplied length
| Readhead compatibility |
RGS40-G ![]() | ±4.2 µm/m | 40 µm | ~8 µm/m/°C | Up to 1.01 m |
Stainless steel tape with track option
Scale name | Accuracy | Scale pitch | Coefficient of thermal expansion at 20 °C | Supplied length | Readhead compatibility |
RTLR40 with optional FASTRACK™ ![]() | ±15 µm/m | 40 µm | 10.1 ±0.2 µm/m/°C
| Up to 10 m |