Overview
IEC 62496-2-4:2013 is an international standard developed by the International Electrotechnical Commission (IEC) focusing on optical circuit boards (OCBs). This standard defines a basic test and measurement procedure for assessing optical transmission in OCBs without input/output (I/O) fibres. The method prescribed uses direct illumination of the optical input ports and captures the emitted optical intensity from output ports through an area image sensor. By evaluating the relative optical losses compared to a control sample, the test determines if an optical circuit board passes or fails quality criteria.
The core advantage of this standard’s test method is the elimination of complex alignment processes between launch fibres and OCBs, permitting a more efficient, uniform, and reliable inspection process.
Key Topics
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Direct Illumination Testing
IEC 62496-2-4 specifies that the input ports of the OCB are uniformly illuminated over an area larger than the core to avoid the need for launch fibre alignment.
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Optical Intensity Monitoring Using Area Image Sensors
Two-dimensional array sensors such as CCD or CMOS capture the radiance of the output ports, enabling high-resolution imaging and intensity measurement.
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Calculation of Excess Optical Loss
The test calculates relative optical losses by comparing the total detected optical intensity of the sample with that of a known control sample, offering a quantitative pass/fail evaluation.
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No Input/Output Fibre Requirement
The test targets optical circuit boards without attached fibres, enhancing testing efficiency for surface or end-face input/output designs.
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Measurement Conditions and Equipment Setup
Includes specifications on light source systems, observation optics, data processing units, and sample holding mechanisms, ensuring repeatability and accuracy of results.
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Image Processing and Data Analysis
Procedures for capturing images, binarization for port range detection, and calculation of summed pixel intensity form an essential aspect of the evaluation process.
Applications
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Quality Assurance for Optical Circuit Boards
Manufacturers can employ this test to verify that OCBs meet optical transmission standards before integration into larger optical communication systems.
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Production Line Inspection
The standard facilitates quick and repeatable pass/fail results, ideal for inline testing and maintaining consistent manufacturing quality control.
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Non-Contact Inspection of OCBs
Since fibre alignment is unnecessary, this method is beneficial for testing boards with delicate surfaces or complex geometries where physical fibre coupling is impractical.
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Evaluation of Optical Losses in Photonic Components
The standard helps in diagnosing loss factors in OCBs, contributing to overall system performance optimization in optical communication networks.
Related Standards
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IEC 62496 Series
Part of the umbrella series covering basic test and measurement procedures for optical circuit boards, with additional parts addressing different configurations and test methods.
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IEC 60068-1: Environmental Testing
Normatively referenced for environmental conditions during testing, ensuring robustness and reliability of test results under controlled environments.
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Other IEC Fibre Optics Standards
Coordination with IEC Technical Committee 86 standards, which govern testing of fibre optic components and systems, to maintain harmonization across optical testing protocols.
Keywords: optical circuit board test method, OCB optical transmission testing, area image sensor optical measurement, IEC 62496-2-4, optical loss measurement, non-contact optical testing, fibre-free optical board inspection, optical quality assurance, IEC optical standards, photonic device testing.