1、Designation: E1936 03 (Reapproved 2011)Standard Reference Radiograph forEvaluating the Performance of Radiographic DigitizationSystems1This standard is issued under the fixed designation E1936; the number immediately following the designation indicates the year oforiginal adoption or, in the case of
2、 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 reference radiograph covers a series of test targetssuitable for evaluating, quantifying,
3、and documenting perfor-mance parameters of the radiographic digitization process orthe electronic image reconstruction process, or both. Thisreference radiograph can be used for visual and electronicanalysis of digitization systems. This is the first of three relatedstandards. Subsequent standards w
4、ill provide guidance on theuse of the test targets and recommended system performancelevels1.2 This reference radiograph provides a series of testtargets to provide a vehicle for the evaluation of spatialresolution, density contrast sensitivity, dynamic range, andspatial linearity as well as other a
5、spects of a digitizationsystem. The test targets are suitable for evaluating a digitiza-tion system with a spatial resolution down to ;1/1000 in. (25micrometres () a density contrast sensitivity down to 0.02optical density (OD), a density range of 0.5 to 4.5 OD, and afilm size capacity of 14 in. (35
6、5 mm) wide by 17 in. (431 mm)long.1.3 The values stated in inch-pound units are to be regardedas the standard, with the exception of the spatial resolutiontargets (6.2 and 6.7) which are stated in SI units.1.4 This standard does not purport to address the safetyconcerns, if any, associated with its
7、use. It is the responsibilityof the user of this standard to establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E1079 Practice for Calibration of Transmission Densitom-etersE1254 Guide for
8、Storage of Radiographs and UnexposedIndustrial Radiographic FilmsE1316 Terminology for Nondestructive ExaminationsE1411 Practice for Qualification of Radioscopic Systems2.2 ASME Standard:Section V,Article 2, MandatoryAppendix VI, Digital ImageAcquisition, Display, Interpretation and Storage forNucle
9、ar Applications32.3 ASTM Adjuncts:Standard Reference Radiograph for Evaluating the Perfor-mance of Radiographic Digitization Systems43. Terminology3.1 Definitions:3.1.1 Refer to Terminology E1316 for definitions of termsused in this guide.3.2 Definitions of Terms Specific to This Standard:3.2.1 conv
10、erging line pairsthe targets located on thereference radiograph that are used to determine the spatialresolution of the digitization system.3.2.2 parallel line pairsthe targets located on the refer-ence radiograph that are used in conjunction with the converg-ing line pairs to determine the spatial
11、resolution of thedigitization system.3.2.3 reference radiographthe single piece of industrialradiographic film containing all of the reference targets de-scribed in this document.3.2.4 scan lineit is a path that is one pixel high (vertical)by the number of pixels wide (horizontal), that is captured
12、bythe digitization system. The scan lines are added, one on top ofthe other, to electronically reproduce the physical (analog) datain the horizontal (film width) and vertical (film length) direc-tions on the display monitor.3.2.5 spatial linearitythe accuracy to which a digitizationsystem reproduces
13、 the physical dimension. It is assessed withina single scan line and from one scan line to the next (horizontaland vertical directions).1This reference radiograph is under the jurisdiction ofASTM Committee E07 onNondestructive Testing and is the direct responsibility of Subcommittee E07.02 onReferen
14、ce Radiological Images.Current edition approved Dec. 1, 2011. Published March 2012. Originallyapproved in 1997. Last previous edition approved in 2007 as E1936 - 03(2007).DOI: 10.1520/E1936-03R11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at
15、 serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American Society of Mechanical Engineers (ASME), ASMEInternational Headquarters, Three Park Ave., New York, NY 10016-5990, http:/www.asme.org.4Availa
16、ble from EPRI NDE Center, NDE Division, 1300 Harris Blvd., Charlotte,NC 28262.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.6 spatial resolutionit is measured as the minimumdistance detectable between two physically spaced line
17、s (see6.2 spatial resolution targets). It is determined by the samplingrate in physical two-dimensional space and the system un-sharpness.3.2.7 targetsthe physical patterns on the reference radio-graph that are used to evaluate the radiographic film digitiza-tion system.4. Significance and Use4.1 Th
18、is reference radiograph may be used to quantify theperformance characteristics of a radiographic digitization sys-tem or to provide periodic evaluations of a digitization systemin a production mode to verify that appropriate operatingcharacteristics are being maintained. This reference radiographpro
19、vides a means for verifying the performance of a digitiza-tion system in much the same way that the tests described inPractice E1411, provide for the verification of a radioscopicimaging system. It may be used to evaluate the performance ofa digitization system in accordance with the requirementscon
20、tained in ASME Section V, Article 2, Mandatory AppendixVI, or other documents invoking requirements of this referenceradiograph.4.2 This reference radiograph provides a tool that allows theuser to determine the performance of their radiographic digi-tization system. This reference radiograph may be
21、used, wherethere is no other applicable document, for establishing recordsof quality and acceptable levels of performance between thecognizant engineering organization and purchaser of inspectedcomponents. This reference radiograph does not provide guid-ance on use of the test targets or recommend s
22、ystem perfor-mance levels.5. Preparation of Reference Radiograph5.1 The optical densities specified in 6.3 and 6.4 of thisdocument are ascertained using densitometry equipment andtechniques in accordance with Practice E1079, and are sup-plied with the adjunct reference radiograph. Optical densitiesa
23、re recorded in the center 0.12 in. (3 mm) of each of the densitytargets in 6.3 and 6.4.5.2 Film DeteriorationRadiographic film is subject towear and tear from handling and use. The extent to which theimage deteriorates over time is a function of storage condi-tions, care in handling, and amount of u
24、se. Reference radio-graphic film is no exception and may exhibit a loss of imagequality over time. The reference radiograph should therefore beexamined each time it is used for signs of wear and tear,including scratches, abrasions, stains, and so forth. A referenceradiograph that shows signs of exce
25、ssive wear and tear, whichcould influence the interpretation and use of the referenceradiograph, should be replaced. A guide for the storage of thereference radiograph is described in Guide E1254.6. Description of Targets6.1 The reference radiograph has five types of targets thatmay be used to evalu
26、ate various parameters of the digitizationsystem. The targets are located within a background density of 3.0 OD. The reference radiograph is divided into three areaswith sizes of 8 in. (203 mm) by 10 in. (254 mm), 11 in. (279mm) by 14 in. (355 mm), and 14 in. (355 mm) by 17 in. (430mm). These have b
27、een created for digitization systems unableto accommodate film sizes up to 14 in. by 17 in. The referenceradiograph may be cut to custom fit a particular digitizationsystem and still contain all of the necessary targets within eachof these areas that are represented on the illustration in Fig. 1.6.2
28、 Spatial Resolution TargetsThese consist of three iden-tical groups of at least 6 converging line pairs. The targets havea maximum resolution of no less than 20 line pairs permillimetre (lp/mm) and a minimum resolution of no greaterthan 1 lp/mm. The three line pair groups are oriented in the 0,45, a
29、nd 90 positions. The maximum resolution is orientedtoward the corners of the reference radiograph, Referencemarks are provided to indicate spatial resolution at levels of 1,2, 3, 4, 5, 6, 7, 8, 9, 10, 15, and 20 lp/mm.6.3 Density Contrast Sensitivity TargetsThese consist of0.4 in. (1 cm) by 0.4 in.
30、fields centered in 1.6 in. (4 cm) by 1.6in. blocks of a slightly lower density. Two series of blocks willbe used, one block series with an optical density of 2.00 ODon a background of 1.95 OD, an optical density change of0.05. The second block series will have 3.50 OD on abackground of 3.40 OD, an o
31、ptical density change of 0.10.The relative density change is more important than the absolutedensity. These 2 block series are grouped in no less than sixareas on the reference radiograph.6.4 Stepped Density TargetsThese targets are to be used todetermine dynamic range and density contrast sensitivi
32、ty. Theyshall consist of a series of 0.4 in. (1 cm) by 0.4 in. blocks withdensities of 0.5 to 4.5 OD. There shall be no less than 13 blocksaligned in a row with the following approximate densities: 4.5,4.02, 4, 3.5, 3.02, 3, 2.5, 2.02, 2, 1.5, 1.02, 1, and 0.5 OD.These blocks are grouped in no less
33、than eight areas on thereference radiograph.6.5 Sharp Edge TargetEach stepped density target (cor-responding to 6.4) with the density 0.5 OD shall have sharpedges to the background of 3.0 OD. The unsharpness of thesharp edges shall be less than 10 micron (0.0004 in.). Thissharp edge shall be used to
34、 measure horizontal and vertical linespread functions by differentiation of step profiles. The nor-malized magnitude of the Fourier transform of a line spreadfunction yields the Modulation Transfer Function (MTF).6.6 Linearity TargetsThese targets provide 1.0 in. (25.4mm) units of measure. They shal
35、l be located in the horizontalas well as the vertical directions. The linearity targets, ormeasurement scale, divides the reference radiograph into threedistinct film sizes 8 by 10 in. (203 by 254 mm), 11 by 14 in.(279 by 355 mm), and 14 by 17 in. (355 by 430 mm).6.7 Parallel Line Pair TargetThis ta
36、rget consists of aparallel line pair gage with a resolution starting at no greaterthan 0.5 lp/mm and increases to a resolution of no less than 20lp/mm. This target may be used to determine spatial resolution.It is positioned near the center of the 8 by 10 in. (203 by 254mm) area on the reference rad
37、iograph.6.8 Additional targets may be located on the referenceradiograph as long as they do not interfere with the digitization,or interpretation, of the targets located in 6.2 through 6.7.E1936 03 (2011)2FIG. 1 Representation of the AdjunctE1936 03 (2011)37. Keywords7.1 density contrast sensitivity
38、; digitization; line pairs; ref-erence radiograph; spatial linearity; spatial resolution; systemevaluation; target; X-rayASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expres
39、sly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised,
40、 either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may at
41、tend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States.
42、 Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).E1936 03 (2011)4
