1、Designation: E1936 03 (Reapproved 2011)1Standard 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 o
2、f 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.1NOTEReference source information was updated editorially in November 2014.1. Scope1.1 This reference radi
3、ograph covers a series of test targetssuitable for evaluating, quantifying, 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
4、systems. This is the first of three relatedstandards. Subsequent standards will 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
5、contrast sensitivity, dynamic range, andspatial linearity as well as other aspects 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 (
6、OD), a density range of 0.5 to 4.5 OD, and afilm size capacity of 14 in. (355 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
7、does not purport to address the safetyconcerns, if any, associated with its 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:2E
8、1079 Practice for Calibration of Transmission Densitom-etersE1254 Guide for Storage of Radiographs and UnexposedIndustrial Radiographic FilmsE1316 Terminology for Nondestructive ExaminationsE1411 Practice for Qualification of Radioscopic Systems2.2 ASME Standard:Section V, Article 2, Mandatory Appen
9、dix VI, Digital ImageAcquisition, Display, Interpretation and Storage forNuclear Applications32.3 ASTM Adjuncts:Standard Reference Radiograph for Evaluating the Perfor-mance of Radiographic Digitization Systems3. Terminology3.1 Definitions:3.1.1 Refer to Terminology E1316 for definitions of termsuse
10、d in this guide.3.2 Definitions of Terms Specific to This Standard:3.2.1 converging 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
11、used in conjunction with the converg-ing line pairs to determine the spatial resolution of thedigitization system.1This reference radiograph is under the jurisdiction ofASTM Committee E07 onNondestructive Testing and is the direct responsibility of Subcommittee E07.02 onReference Radiological Images
12、.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 serviceastm.org. For
13、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.Copyright ASTM International,
14、 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2.3 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 numbe
15、r of pixels wide (horizontal), that is captured 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 a
16、ccuracy to which a digitizationsystem reproduces the physical dimension. It is assessed withina single scan line and from one scan line to the next (horizontaland vertical directions).3.2.6 spatial resolutionit is measured as the minimumdistance detectable between two physically spaced lines (see6.2
17、 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 This refere
18、nce 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 radiographprovides a m
19、eans 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 requirementscontained in
20、 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 used, whe
21、rethere 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 system per
22、for-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 densitiesare record
23、ed 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 storageconditions, care in handling, and amount of use. Referen
24、ceradiographic film is no exception and may exhibit a loss ofimage quality over time. The reference radiograph shouldtherefore be examined each time it is used for signs of wear andtear, including scratches, abrasions, stains, and so forth. Areference radiograph that shows signs of excessive wear an
25、dtear, which could influence the interpretation and use of thereference radiograph, should be replaced. A guide for thestorage of the reference radiograph is described in GuideE1254.6. Description of Targets6.1 The reference radiograph has five types of targets thatmay be used to evaluate various pa
26、rameters 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 been created fo
27、r 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 Spatial Resol
28、ution 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, and 90 position
29、s. 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. fields centere
30、d 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 optical density
31、 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 sensitivity. Theyshall
32、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 than eight are
33、as on thereference radiograph.6.5 Sharp Edge TargetEach stepped density target (corre-sponding 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 measure horiz
34、ontal 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).E1936 03 (2011)126.6 Linearity TargetsThese targets provide 1.0 in. (25.4mm) units of measure. They s
35、hall be located in the horizontalas well as the vertical directions. The linearity targets, ormeasurement scale, divides the reference radiograph into threeFIG. 1 Representation of the AdjunctE1936 03 (2011)13distinct film sizes 8 by 10 in. (203 by 254 mm), 11 by 14 in.(279 by 355 mm), and 14 by 17
36、in. (355 by 430 mm).6.7 Parallel Line Pair TargetThis target 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
37、the 8 by 10 in. (203 by 254mm) area on the reference radiograph.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 6.7.7. Keywords7.1 density contrast sensitivity; digitizati
38、on; 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 expressly advised
39、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, either reap
40、proved 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 attend. If you
41、 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. Individual
42、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 Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 03 (2011)14
