TONiC™ UHV incremental encoder system with RSLM20 linear scale
Features
- Readhead size: 35 x 13.5 x 10 mm
- Resolutions to 1 nm
- Speed up to 10 m/s
- Analogue or digital outputs
- Ultra-low Sub-Divisional Error (SDE): typically <±30 nm
- Optical IN-TRAC™ reference mark
Benefits
- Ultra-High Vacuum (UHV)
- High accuracy spar scale
- Super-compact encoder with dynamic signal conditioning for improved motion control
- Diagnostic kit to assist challenging installations and aid system optimisation

What is TONiC UHV?
TONiC UHV brings Renishaw's super-compact, non-contact encoder system to Ultra-High Vacuum applications offering customers improved motion control.
TONiC offers speeds up to 10 m/s and, combined with the Ti interface, resolutions down to 1 nm for both linear and rotary applications. TONiC systems are quick and simple to install with wide set-up tolerances and calibration at the push of a button. TONiC's dynamic signal processing gives improved signal stability with ultra-low Sub-Divisional Error of typically <±30 nm to help realise superior motion control performance.
What is RSLM20 scale?
RSLM20 is a stainless steel spar scale featuring 20 µm pitch and a variety of IN-TRAC optical reference mark options, including regularly spaced for customer selection or single reference at the centre or close to the end.
It is comparable to fine pitch glass scales and offers a total accuracy (including slope and linearity) better than ±4 µm over a 5 m length. It can also be coiled for simple storage and handling yet once uncoiled behaves as a spar scale.
System designers can choose between specially formulated adhesive tape or mechanical clips to suit mounting requirements. Both mounting methods allow for independent thermal expansion to that of the substrate.
Why choose this encoder system?
Ultra-High Vacuum (UHV)
TONiC UHV readheads take standard TONiC outstanding performance and deliver it in a readhead that has been designed and constructed using UHV compatible materials and processes making it suitable for UHV conditions down to 10 -10 Torr.
The range of TONiC UHV encoders and accessories are constructed from vacuum-compatible materials and adhesives to give low outgassing rates and proven clean residual gas analysis (RGA) making them suitable for many applications including wafer handling / testing, scientific instruments, spectroscopy, vacuum inspection equipment and many more.
Combines rugged reliability with higher accuracy
The TONiC RSLM20 system offers the convenience, ruggedness and ease of use of a tape scale yet offers a higher accuracy than glass scales making it ideal for long length, high performance axes.
Ultimate reliability and performance in a compact size
For ultimate reliability and consistent performance TONiC readheads incorporate third-generation filtering optics, tuned for even lower noise (jitter) and now further enhanced by dynamic signal processing including Auto Gain Control and Auto Offset Control. This combination – all incorporated inside the readhead - provides signals of unrivalled purity and ultra-low Sub-Divisional Error of just ±30 nm. The result is smoother velocity control for improved scanning performance, increased positional stability which in turn helps minimise the heat build-up in motors inside the vacuum; essential parameters for vacuum applications all in a compact readhead.
Quicker and easier installation
A set-up LED on the readhead gives a visual indication of signal size and an optional diagnostic kit allows remote checking of the system performance when the readhead is concealed within the machine. Calibration of the reference mark and incremental signals is done at the push of a button with no mechanical adjustment or additional diagnostic tools. The IN-TRAC customer-selectable optical reference mark is embedded in the incremental scale for compact dimensions and simplified alignment. This yields a reference mark output that is bi-directionally repeatable to unit of resolution over the full operating temperature and speed range.
Interface options
TD (dual resolution) interface
- Selectable dual-resolutions quadrature output.
- Ideal for applications that require high speed movement combined with finer precision motion.
DOP (dual output) interface
- Provides simultaneous digital quadrature and 1 Vpp signals.
- Designed for applications requiring one or more operations to be synchronised with a motion axis.
Optional diagnostic kit

TONiC diagnostic software can be used to optimise the installation of TONiC encoders and provide a quick and comprehensive system calibration. The software must be used in conjunction with the TONiC diagnostic hardware which can be purchased from Renishaw using part number A-9411-0011. The hardware is connected to the PC via the USB cable (provided in the kit) or in-line with the customers' electronics.
Find out all about the TONiC diagnostic kit.
Technical specifications
Measuring standard | RSLM20: high accuracy stainless steel spar scale Also available with end reference mark as RSLE20, and with selectable reference mark as RSLC20 |
Readhead size (LxWxH) | 35 mm x 13.5 mm x 10 mm |
Scale pitch | 20 μm |
Coefficient of thermal expansion at 20 °C | 10.1 ±0.2 μm/m/°C |
Accuracy grade at 20 °C | ±1.5 μm up to 1 m, ±2.25 μm up to 2 m, ±3 μm up to 3 m, ±4 μm up to 5 m, calibration traceable to international standards |
Reference mark | IN-TRAC reference mark Various reference mark position options, see data sheet for details |
Limit switches | Dual or single limits (select at time of order) |
Scale length | 80 mm to 5 m |
Maximum speed Analogue Digital | (See data sheet for details) Up to 10 m/s at -3 dB Up to 10 m/s |
Sub-Divisional Error (SDE) | Typically <±30 nm |
Dynamic signal control | Real time signal conditioning including Auto Gain Control (AGC) and Auto Offset Control (AOC) for optimised performance during operation |
Incremental signals Analogue Digital | 1 Vpp (20 μm period) Resolutions from 5 μm to 1 nm |
Electrical connection | 0.5 m, 1 m, 1.5 m, 3 m, 5 m and 10 m cable lengths with mini connector (connects direct to TONiC interface) |
Power supply | 5 V ±10%, <100 mA (analogue system), <200 mA (digital systems) (unterminated) |
Readhead power consumption | <100 mA |
Vibration (operating) | 100 m/s2 max @ 55 Hz to 2 000 Hz |
Shock (non-operating) | 1 000 m/s2, 6 ms, ½ sine |
Operating temperature (system) | 0 °C to +70 °C |
Bake-out temperature (non-operating) | 120 °C (Readhead and scale only) |
Sealing | Readhead: IP20 Interface: IP20 |
Cable construction | Tinned copper braided single screen, FEP core insulation |
Refer to data sheets for full details.