SMD-04B

Metrology and precision 3-channel Encoder module

Key Features

Accurate Encoder Performance
- High resolution 20 µm track period
  - 1270 LPI (Lines per Inch) / 50 Lines per mm
  - Quadrature output is 5080 LPI / 200 Lines per mm
- Low noise A/B analog and digital Z (index) outputs
  - Low distortion Lissajous curve reduces cyclical errors and improves interpolation repeatability and accuracy
- Lower assembly & manufacturing costs
  - Proven reliability and long lifetime
  - Small footprint and 1.0mm package height fits within existing hardware
  - Optimized OEIC and optics design for easier mounting alignment

Typical Applications

Metrology, CMM
Laser optical axis control
Assembly machines
Measuring instruments
Precision rotary and linear encoders
Stages, Actuators
Robotics

The SMD-04B is a miniature, reflective optical incremental encoder head with 3-Channel outputs (2 analog A/B plus Digital Z index)

The SMD-04B is the building block for maximizing resolution and accuracy with interpolation.

Combined with a 20µ period scale there are 50 periods per mm/1270 periods per inch. Quadrature differential A& B outputs are 4x 200 counts per mm/ 5080 per inch.

SMD-04B low-noise high-precision analog output signals maximize accuracy and enables high bit ADC interpolation into picometer resolution.

A unique LED receptor provide wider tolerance to misalignment, YAW, external contamination and humidity.

Footprint is 5.4x4.3mm and package height 1.0mm with nominal 0.5mm gap to scale for overall height 1.5mm from PCB to scale.

20µm Resolution and Interpolation
Encoding	Imperial		Metric
Encoding	LPI (lines per inch)	Resolution	LPM (lines per mm)	Resolution
×1	1270 LPI	0.787 mils	50 LPM	20µm
Quadrature A-B ×4	5080 LPI	0.197 mils	200 LPM	5µm
With external ADC 12-bit Interpolation	20,807,680 LPI	0.0000481 mils	819,200 LPM	0.0012207µm
With external ADC 16-bit Interpolation	332,922,880 LPI	0.00000300625 mils	13,107,200 LPM	0.07629375nm