Inside DADI Factory - Part 2: How Absolute Encoder Disks Are Inspected for Angle Measurement
Before an absolute encoder disk moves into surveying instrument assembly, DADI engineers inspect the component under a microscope. The inspection shown here focuses on visible surface condition and the definition of the etched code pattern used in the instrument's angle-measurement system.
What Is an Absolute Encoder Disk Used For?
In DADI surveying instruments, the absolute encoder disk is part of the angle-measurement system. Its encoded pattern is read by the instrument to determine angular position. Because the disk forms part of this measurement chain, its visible surface condition and code definition are checked before assembly.
Figure 1. Microscopic inspection of a DADI absolute encoder disk before surveying instrument assembly.
How Is the Encoder Disk Inspected?
The engineer examines the encoder disk through an industrial microscope. In the factory process shown here, the inspection focuses on two visible factors: the condition of the optical surface and the clarity of the etched code pattern.
The disk surface is checked for visible dust, smudges and other contamination before the component proceeds to assembly.
The microscopic code pattern is examined for clear line definition before the disk moves forward in the production process.
Why Does This Inspection Matter for Angle Measurement?
The encoder disk is part of the instrument's angular-position sensing system. Inspecting it before assembly helps identify visible contamination or unclear code features before the component is installed. This step supports a more controlled starting condition for subsequent assembly, calibration and quality inspection.
What Is Checked Under the Microscope?
The factory process documented here is a visual component-level inspection. The microscope allows the engineer to examine details that are difficult to assess with the unaided eye, including small areas of contamination, surface marks and the definition of the etched code lines.
DADI Engineering Note
The factory image on this page documents a real component-inspection step inside DADI's angle-measurement manufacturing process. It shows an engineer using a microscope to inspect an absolute encoder disk before assembly.
The available record documents the inspection method and visible inspection targets shown here. It does not provide a numerical surface-defect tolerance, code-line tolerance or final angular-accuracy result, so those values are not claimed on this page.
Which DADI Instruments Use Absolute Angle Encoding?
DADI uses absolute angle-reading technology in surveying instruments including total stations and electronic theodolites. The encoder disk is therefore one component within the broader angle-measurement architecture used by these instrument categories.
Frequently Asked Questions
What is inspected on an absolute encoder disk?
The factory process shown here checks the disk's visible surface condition and the definition of its etched code pattern under a microscope.
Why is a microscope used?
A microscope allows the engineer to examine small areas of contamination, surface marks and code-line definition that are difficult to evaluate with the unaided eye.
Is the encoder disk developed by DADI?
Yes. In this factory process, DADI identifies the absolute encoder disk as a self-developed component used in its angle-measurement system.
Does microscopic inspection alone determine the final angular accuracy?
No. Encoder-disk inspection is one component-level quality step. Final angular performance also depends on assembly, axis geometry, calibration and other inspection procedures.
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