ASTM_D_7310_-_21.pdf

Designation:D731021Standard Practice forDefect Detection and Rating of Plastic Films Using OpticalSensors1This standard is issued under the fixed designation D7310;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice intends to provide standardized ap-proaches and criteria for the observation and reporting ofdefects in various types of plastic film,by means of an opticalscanning system.Scope includes the in situ inspection ofdefects in films fabricated for specific applications after prepa-ration of a suitable film from plastic resin.1.2 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.NOTE1There is no known ISO equivalent to this standard.1.3 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsE456 Terminology Relating to Quality and StatisticsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE2587 Practice for Use of Control Charts in StatisticalProcess Control3.Terminology3.1 DefinitionsFor definitions of terms that appear in thispractice relating to plastics,refer to Terminology D883.3.2 Definitions of Terms Specific to This Standard:3.2.1 defectfor the purpose of this practice any entity inthe film that is large enough to be detected by an optical sensorand is either polymeric in nature or caused by degradation,external contamination,undispersed additives or pigments,orsimilar sources.3.2.1.1 DiscussionIn Appendix X1,some types of defectsare shown(cross-linked material,un-molten polymer,pin-holes).The defects can be classified in three groups:3.2.1.1 gelparticle of plastic material in the film matrixnot blended with the matrix and often acting as a miniaturelens.Several types of gels exist.3.2.1.2 contaminationany particle in or on the film matrixaffecting irradiated light differently than the matrix(dirt,insects,oxidized additives or material,catalyst residues,solidparticles,metallic particles,undispersed pigments or additives,etc.).3.2.1.3 structural defectvisual deviation not caused bygels or contaminations,for example,air bubbles,wrinkles,dielines,film holes,sharkskin,arrowheads.3.2.2 pixel3.2.2.1 in a picturesmallest element of an image that canbe individually processed by a video display system or aphysical point in a raster image.3.2.2.1 DiscussionThe greater the number of pixels perarea,the higher the resolution.3.2.2.2 in a camerasmallest single photo-electrical detec-tor element of the camera sensor.3.2.3 effective pixel sizeactual size of the individual pixelsin the analyzed image.3.2.3.1 DiscussionThe effective pixel size of the opticalsystem is determined by the physical pixel size of the sensorand a magnification factor caused by the lens of the camera.3.2.4 resolution3.2.4.1 imagethe detail an image holds,also called pixeldensity.3.2.4.1 DiscussionHigher resolution means more imagedetail,often expressed in pixels per inch or dots per inch.3.2.4.2 cameraresolution of the sensor:the sheer numberof pixels on the sensor;the amount of detail that a camera cancapture,measured in pixels(for example,4k-camera).1This practice is under the jurisdiction ofASTM Committee D20 on Plastics andis the direct responsibility of Subcommittee D20.19 on Film,Sheeting,and MoldedProducts.Current edition approved Sept.1,2021.Published September 2021.Originallyapproved in 2007.Last previous edition approved in 2020 as D7310-20.DOI:10.1520/D7310-21.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.13.2.5 optical resolutiondescribes the ability of an imagingsystem to resolve detail in the object that is being imaged.3.2.5.1 DiscussionIt is t