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QUANTiC™ incremental encoder system with RESM40 rotary (angle) ring


  • Operating rideheight tolerance ±0.2 mm
  • Digital output direct from the readhead
  • Readhead size: 35 x 13.5 x 10 mm
  • Resolutions to 50 nm
  • Speed up to 8 800 rpm
  • Excellent dirt immunity
  • Optical IN‑TRAC™ reference mark


  • Easy installation
  • No separate interface required
  • Compatible with the Advanced Diagnostic Tool ADTi-100 for easy fault finding, challenging installations and servicing
  • Low-profile ring with large internal diameter for easy integration
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What is QUANTiC?

The QUANTiC encoder series integrates Renishaw's filtering optics design and interpolation technology to create a high performance, super-compact, digital all-in-one incremental open optical encoder. QUANTiC encoder systems are easy to install with exceptionally wide installation and running tolerances, along with built-in installation and calibration functions. Further diagnostic information can be accessed by using the Advanced Diagnostic Tool ADTi‑100 and ADT View software during installation or for in‑field diagnostics and fault finding. Speeds up to 8 800 rpm can be achieved to meet the most demanding motion control requirements. The QUANTiC encoder offers resolutions down to 50 nm and a wide range of configurations, making optimisation easy and simple. Dynamic signal processing gives improved signal stability to achieve superior performance from your motion control system.

What is RESM40 ring?

RESM40 is a one-piece stainless steel ring with 40 µm pitch incremental graduations marked directly on the periphery, featuring the IN-TRAC optical reference mark. Two versions are available in a wide range of sizes (Ø52 mm to Ø550 mm): ‘A' section rings, which offer an impressive installed accuracy and feature a taper mount system, reducing the need for highly toleranced machined parts and eliminating eccentricity; and ‘B' section thin rings, which have low inertia and mass. Both 'A' and 'B' section rings have a large internal diameter for flexible integration. The non-contact format eliminates backlash, shaft wind-up (torsion) and other mechanical hysteresis errors that are inherent in traditional enclosed encoders.

Why choose this encoder system?

Easy installation

In OEM applications, machine build time is critical, as time saved in component installation allows shorter manufacturing lead times and ultimately higher profitability. The QUANTiC encoder series helps to fulfil this need with its wide set-up tolerances for an incremental product (yaw tolerance ±0.9° and rideheight tolerance ±0.15 mm) and integrated set-up LED on the readhead. With increased installation tolerances, production will benefit from a faster installation process, reduced overheads and an increase in throughput.

All purpose digital encoder system

QUANTiC is the encoder of choice because it combines high speed interpolation with impressive metrology performance, making it suitable for even the most demanding applications. The configurations available help the user optimise the speed and resolution of their system depending on their motion control requirements. Furthermore, the QUANTiC readhead works with both linear and rotary (angle) scales. It is quick and easy to install, making it particularly suitable for volume production.

High dirt immunity

The QUANTiC encoder system is highly immune to dirt and contamination due to several advanced design features. QUANTiC readheads incorporate Renishaw's well established filtering optics that average the contributions from many scale periods and effectively filter out non-periodic features such as dirt. Measurement signals are further enhanced by a range of electronic signal processing algorithms such as Auto Gain Control (AGC), Auto Offset Control (AOC) and Auto Balance Control (ABC). QUANTiC encoders also feature a third layer of signal filtering from a new detector design, which helps to eliminate non-harmonic signal frequencies that can occur due to contamination on the scale. These signal conditioning features combine to ensure low Sub-Divisional Error (SDE) and minimal signal variation over contamination.

Optional Advanced Diagnostic Tool ADTi-100

Advanced Diagnostic Tool ADTi-100

The QUANTiC encoder system is compatible with the Advanced Diagnostic Tool ADTi-100 and ADT View software. They provide comprehensive real-time encoder data feedback to aid more challenging installations and diagnostics. The intuitive software interface can be used for:

  • Remote calibration
  • Signal optimisation over the entire axis length
  • Readhead pitch indication
  • Limit and reference mark indication
  • Digital readout of encoder position (relative to the scale)
  • Monitoring the velocity against time graph
  • Exporting and saving data

Technical specifications

Measuring standard

One-piece low profile stainless steel ring. Standard ‘A' section with tapered internal diameter or low inertia ‘B' section rings available

Readhead size (LxHxW)

35 mm x 13.5 mm x 10 mm

Scale pitch

40 μm

Coefficient of thermal expansion at 20 °C15.5 ±0.5 µm/m/°C

Ring outer diameter

52 mm to 550 mm. For larger custom sizes, contact Renishaw

Line count

4 096 to 43 200 (depending on ring size)

Reference mark

Single IN-TRAC reference mark


Graduation accuracy

System accuracy

±3.97 to ±0.38 arc seconds (depending on ring diameter)

±4.6 to ±0.44 arc seconds (depending on ring diameter)

Maximum speed

8 800 rpm (for 52 mm diameter ring)

(See data sheet for details)

Sub-Divisional Error (SDE)

Typically <±80 nm for Ø <135 mm

Typically <±150 nm for Ø >135 mm

Dynamic signal control

Real time signal conditioning including Auto Gain Control (AGC), Auto Balance Control (ABC) and Auto Offset Control (AOC) for optimised performance across a range of operating conditions

Incremental signals

10 µm to 50 nm resolution

(See data sheet for details of angular resolutions)

Electrical connection

0.2 m, 0.5 m, 1 m, 1.5 m, 2 m and 3 m cable lengths with D-type connectors (9 and 15 pin) or circular in-line connector (12 pin)

0.5 m, 1 m, 3 m cable lengths with 14-way JST connector

Power supply

5 V -5%/+10%, typically <200 mA fully terminated

Vibration (operating)

100 m/s2 max at 55 Hz to 2 000 Hz, 3 axes

Shock (operating)

500 m/s2, 11 ms, ½ sine, 3 axes

Operating temperature

0 °C to +70 °C



* System accuracy is graduation error plus SDE. Graduation accuracy is the maximum difference between the angle measured by a single readhead and the true rotation of the encoder as graduated. Application disturbances such as eccentricity are not included.

Refer to data sheets for full details.


Data Sheets

White paper

  • White paper:  The accuracy of angle encoders White paper: The accuracy of angle encoders

Technical drawings


How it works

QUANTiC encoders feature the third generation of Renishaw's unique filtering optics that average the contributions from many scale periods and effectively filter out non-periodic features such as dirt. The nominally square-wave scale pattern is also filtered to leave a pure sinusoidal fringe field at the detector. Here, a multiple finger structure is employed, fine enough to produce photocurrents in the form of four symmetrically phased signals. These are combined to remove DC components and produce sine and cosine signal outputs with high spectral purity and low offset whilst maintaining bandwidth to beyond 500 kHz.

Fully integrated advanced dynamic signal conditioning, including Auto Gain, Auto Balance and Auto Offset Controls, ensures low Sub-Divisional Error (SDE) of typically <±80 nm for small rotary systems, typically <±150 nm for large rotary systems and <±80 nm for linear systems.

This evolution of filtering optics, combined with carefully designed electronics, provide incremental signals with wide bandwidth achieving a maximum speed of 8 800 rpm for rotary systems, 24 m/s for linear systems, with the lowest positional jitter (noise) of any encoder in its class. Interpolation is within the readhead, with fine resolution versions being further augmented by additional noise-reducing electronics to achieve jitter down to 2.73 nm RMS.

QUANTiC™ optical scheme with annotations

The IN-TRAC reference mark is fully-integrated in the incremental scale and is detected by a photodetector within the readhead. This unique arrangement also benefits from an automatic calibration routine that electronically phases the reference mark and optimises the incremental signals.