For the most productive incremental optical rotary encoder search, we recommend making your selections in the following order: Line Count, Commutation, Bore Size.

For custom line count/commutation/bore sizes please contact us and a sales engineer will help customize an optical encoder for your application.

Please refer to the bottom of this page for an introduction to incremental optical rotary encoders, and more information on the distinctions between rotary, incremental, and optical encoders.

QM35 EZ-Comm Optical Rotary Encoder

QM35 EZ-Comm Optical Rotary Encoder

Programmable Comm. Alignment
Incremental & Commutation
Full Complement Outputs
Bearingless Modular Design
Low Profile: Ø1.44" x 0.43" H
Standard JAE Connector

QML35 EZ-Comm Optical Rotary Encoder

QML35 EZ-Comm Optical Rotary Encoder

Programmable Comm. Alignment
Incremental & Commutation
Single Ended Outputs
Bearingless Modular Design
Low Profile: Ø1.44" x 0.43" H
Standard Berg (FCI) Connector

QM35 Optical Rotary Encoder

QM35 Optical Rotary Encoder

Incremental & Commutation
Full Complement Outputs
Low Profile: Ø1.44" x 0.43" H
Bearingless Modular Design
1 MHz Frequency Response
Standard JAE Connector

QML35 Optical Rotary Encoder

QML35 Optical Rotary Encoder

Incremental & Commutation
Single Ended Outputs
Low Profile: Ø1.44" x 0.43" H
Bearingless Modular Design
1 MHz Frequency Response
Standard Berg (FCI) Connector

QM22 Optical Rotary Encoder

QM22 Optical Rotary Encoder

Miniature Package Size:
Ø1.024" x 0.486" H
Full Complement Incremental
Single Ended Commutation
Bearingless Modular Design
Standard JAE Connector

QR145 Optical Rotary Encoder

QR145 Optical Rotary Encoder

Incremental & Commutation
Highly Customizable Options:
IP66 Sealed, 5-26V Operation,
High Temperature, etc.
Ø1.45" x 0.87" H
Flying Leads Cable

QR200 Optical Rotary Encoder

QR200 Optical Rotary Encoder

Incremental & Commutation
Bore Sizes Up To Ø0.625"
Highly Customizable Options:
High Temp, 5-26V Operation, etc.
Ø2.00" x 0.93" H
Flying Leads Cable

QDH20 Optical Rotary Encoder

QDH20 Optical Rotary Encoder

For Industrial Applications
IP66 & IP64 Sealing Standard
Size 20 & 25 Flange and Servo
Cable Gland or MS Connector
5-26V Operation Standard
Line Driver/Open Collector ABZ

QR12 Optical Rotary Encoder

QR12 Optical Rotary Encoder

Ø1.22" x 0.99" H
Highest Resolution Encoder
Sin/Cos or Digital Incremental
High Pole Count Commutation
Standard JAE Connector

LP12 Optical Rotary Encoder

LP12 Optical Rotary Encoder

Low Profile: Ø1.22" x 0.82" H
Highest Resolution Encoder
Sin/Cos or Digital Incremental
High Pole Count Commutation
Standard JAE Connector

HR12 Optical Rotary Encoder

HR12 Optical Rotary Encoder

HEDS/HEDM Compatible Mount
IP52 Sealed
Ø1.42" x 1.12" H
Sin/Cos or Digital Incremental
High Pole Count Commutation

JR12 Optical Rotary Encoder

JR12 Optical Rotary Encoder

Jam Nut Mounting
Size 15 Resolver Style
Ø1.22" x 1.03" H
Sin/Cos or Digital Incremental
High Pole Count Commutation

QR787 Optical Rotary Encoder Shaft Style

QR787 Optical Rotary Encoder Shaft Style

Incremental Solid Shaft
Potentiometer Replacement
Ø0.787" x 0.875" H
Optional 5-26V Operation
Male Pins or Ribbon Cable

QR787 Optical Rotary Encoder Blind Bore Version

QR787 Optical Rotary Encoder Blind Bore Version

Incremental Hollow Bore
Potentiometer Replacement
Ø0.787" x 1.23" H
Optional 5-26V Operation
Male Pins or Ribbon Cable

QR110 Optical Rotary Encoder

QR110 Optical Rotary Encoder

Size 11 Resolver Replacement
Incremental Solid Shaft
Ø1.062" x 0.813" H
Optional 5-26V Operation
Male Pins or Ribbon Cable

Incremental Optical Rotary Encoder Basics

Incremental optical rotary encoders, also known as shaft encoders, are electromechanical position feedback devices. The output data they generate provides information to control systems and allows them to determine position, speed, acceleration, deceleration and travel distance in motion control applications.

An optical encoder consists of the following components: a moveable disc, an LED (Light Emitting Diode) source, a photo detector and a signal processor that converts the analog waveforms to digital waveforms.

The encoder disc, or code wheel, has a pattern of spaces, called windows, on it. When the LED light passes through one side of the disc, the photodiode detects interruptions. The photodiode creates analog signals which are processed and digitized for use by external control devices.

What are Incremental Optical Rotary Encoders Used For?

Industrial and commercial applications that use optical rotary encoders include:

  • Aerospace & Defense
  • Automated Guided Vehicles (AGV)
  • Autonomous Mobile Robots (AMR)
  • Conveyor Applications
  • Elevators
  • Factory Automation
  • Galvanometer Scanners
  • Industrial Controls
  • Medical Devices
  • Off-Highway Vehicles
  • Oil & Gas
  • Passenger Rail
  • Pulp & Paper Mills
  • Robotics
  • Rotating Radar Platforms
  • Servo Motors
  • Steel Mills
  • Stepper Motors
  • String Potentiometers
  • Wood Processing

Learn more about optical encoder applications or contact us for help selecting the best encoder for your specific project.

Rotary Encoders

Rotary encoders, also known as shaft encoders, are electromechanical position feedback devices. The output data they generate provides information to control systems and allows them to determine position, speed, acceleration, deceleration, and travel distance in motion control applications.

They’re called rotary encoders because they measure how far something turns (like a servo motor shaft). This measurement of distance around an axis is called angular position.

For more detail, including a diagram, please visit our page about transmissive rotary encoders.

Incremental Encoders

An incremental encoder is a type of rotary encoder that indicates motion and direction. Incremental encoders work by generating A/B output signals based on a specific number of pulses per rotation. In this way, the angular motion of the shaft is converted into a code (encoded) to determine its position or motion.

Incremental encoders provide information about rotary motor speed and distance. They’re commonly used for industrial motion control applications.

To learn more about how incremental encoders work, visit our page with incremental encoder basics.

Rotary Encoders: Incremental vs. Absolute

An incremental rotary encoder is different from an absolute rotary encoder in the type of information it measures. Incremental encoders measure change in position. Absolute encoders indicate the absolute position, which is a designated starting point. Because the absolute or “zero” position of the shaft is recorded, an absolute encoder provides position data even after a power failure, or if the shaft moves while the encoder is turned off. Incremental encoders require a reset or reference position every time they’re turned on, to locate their position in rotation.

Optical Encoders

An optical encoder is a type of rotary encoder that uses an LED light source, a photodetector (light sensor), and a moveable disc with slotted openings to generate and count light pulses as the shaft turns. Optical encoders are used to measure position, velocity, and acceleration in a variety of applications.

Optical rotary encoders are extremely precise and offer higher resolution (accuracy), making them ideal for applications like machine tools, robotics and CMMs (coordinate measuring machines).

If you’d like to learn more, dive into the technical details behind how optical encoders work or explore:

Optical Incremental Encoder Sales & Support

Since 1989, Quantum Devices has been known for incremental encoder manufacturing innovation. Our full line of high performance encoders fits a wide variety of industries and applications. Buy rotary encoders online direct from our store. To find out which rotary encoder would be best for your specific application, or to request a custom configuration, contact Quantum Devices today.

Log In

Forgot Password?

Create an account

Create an account to gain access to all of our 3D models!

Create Account

Create an account to gain access to all of our 3D models!

Forgot Password