IEC 62899-402-3:2021 pdf download

IEC 62899-402-3:2021 pdf download.Printed electronics – Part 402-3: Printability – Measurement of qualities – Voids in printed pattern using a two-dimensional optical image
1 Scope
This part of IEC 62899 specifies the optical measurement method for acquiring two-dimensional images of voids and obtaining the void-related attributes in the dried or cured printed patterns which are part of the electronic products in the field of printed electronics. The measurable voids using this document are limited to those that are distinguishable by the optical image measurement. NOTE In this document, void means an imperfection of pattern observed from a two-dimensional (2D) top-view.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 291, Plastics – Standard atmospheres for conditioning and testing
3 Terms, definitions and abbreviated terms
For the purposes of this document, the following terms and definitions apply. ISO and IEC maintain terminological databases for use in standardization at the following addresses: ISO Online browsing platform: available at https://www.iso.org/obp IEC Electropedia: available at http://www.electropedia.org/ 3.1 region of interest ROI area, inside defined boundaries, to be analysed 3.2 background area part of the area in the ROI that contains the background, excluding the patterned part 3.3 pattern area part of the area in the ROI that contains the patterned part, and which may include voids, excluding the background 3.4 void absence of ink in an area that should be inked
4 Atmospheric conditions for evaluation and conditioning
The standard atmosphere for evaluation (test and measurement) and storage of the specimen shall be a temperature of (23 ± 2) °C and relative humidity of (50 ± 10) %, conforming to standard atmosphere class 2 specified in ISO 291. For a plastic test piece which is a substrate with printed patterns, the standard atmosphere for evaluation (test and measurement) and storage of the specimen shall be a temperature of (23 ± 1) °C and relative humidity of (50 ± 5) %, conforming to standard atmosphere class 1 specified in ISO 291. Unless otherwise specified, the conditions shall be reported. If conditioning is necessary, the same standard atmosphere specified above shall apply.
5 Measuring methods and instruments
5.1Measuring instrument The measurement of voids in the pattern shall be carried out with an instrument that can obtain the image of the pattern. The repeatability and accuracy of the measuring instrument should be less than 10 % of the tolerance specification of the smallest dimension of the voids that the measurer wants to measure. In the measurement system, the image of the pattern should be converted to an image file. The image should include the pixel information without loss due to compression (e.g. causes of jpeg compression). The pixel dimension or resolution of the image is determined by agreement between the user and supplier; if not, the pixel dimension of the image should be less than half of the smallest dimension of the void that the measurer wants to measure. If working with the resolution instead of the pixel dimension, this requirement should be fulfilled accordingly.5.2 Preparation of specimen The measuring area of the specimen is determined by agreement between the user and supplier. The specimen should be kept flat during the measurement. The specimen to measure voids in the pattern necessarily contains the background area which does not have the pattern. 5.3 Measuring method The printed pattern has the form of a line or solid area and can have voids. For the measurement of voids in the pattern, the boundary between the printed area and the void is recognized and the number and area of the void are calculated using an appropriate software.