DIN 32877-2000 Optoelectronic measurement of distance profile and form《距离、轮廓和形式的光电测量》.pdf

1、Ref. No. DIN 32877 : 2000-08English price group 10 Sales No. 011010.04DEUTSCHE NORM August 200032877Continued on pages 2 to 14. No part of this translation may be reproduced without the prior permission ofDIN Deutsches Institut fr Normung e.V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has th

2、e exclusive right of sale for German Standards (DIN-Normen).Optoelectronic measurement of form,profile and distanceTranslation by DIN-Sprachendienst.In case of doubt, the German-language original should be consulted as the authoritative text.ICS 17.040.30Optoelektronische Abstands-, Profil- und Form

3、messungIn keeping with current practice in standards published by the International Organization for Standardization(ISO), a comma has been used throughout as the decimal marker.ForewordThis standard has been prepared by Technical Committee Geometrische Produktspezifikation und -prfungof the Normena

4、usschuss Technische Grundlagen (Fundamentals in Technology Standards Committee).AmendmentsThis standard differs from the February 1992 edition of DIN 32877, the March 1995 edition of DIN V 32936-1,and the December 1995 edition of DIN V 32936-2 in that it has been revised in form and substance.Previo

5、us editionsDIN 32877: 1992-02; DIN V 32936-1: 1995-03; DIN V 32936-2: 1995-12.1 ScopeThis standard specifies requirements for and the verification of optoelectronic systems used for the meas-urement of form, profile and distances.2 Normative referencesThis standard incorporates, by dated or undated

6、reference, provisions from other publications. Thesenormative references are cited at the appropriate places in the text, and the titles of the publications arelisted below. For dated references, subsequent amendments to or revisions of any of these publicationsapply to this standard only when incor

7、porated in it by amendment or revision. For undated references, thelatest edition of the publication referred to applies.DIN 1319-1 Basic concepts in metrology General conceptsDIN 1319-2 Basic concepts in metrology Terminology relating to the use of measuring instrumentsDIN 1319-3 Basic concepts in

8、metrology Evaluating measurements of a single measurand and expres-sion of uncertaintyDIN 5401 Balls for rolling bearings and general industrial useDIN 17350 Tool steel Technical delivery conditionsSupersedes DIN 32877,February 1992 edition,DIN V 32936-1, March 1995edition, and DIN V 32936-2,Decembe

9、r 1995 edition.Page 2DIN 32877 : 2000-08DIN 55350-13 Terminology in quality assurance and statistics Concepts relating to the accuracy of testmethods and measurement resultsDIN EN 573-3 Aluminium and aluminium alloys Chemical composition and form of wrought products Part 3: Chemical compositionDIN E

10、N 10027-2 Designation systems for steel Numerical systemDIN EN 60068-2-6 Basic environmental testing procedures Part 2: Tests Test Fc: Sinusoidal vibration(IEC 68-2-6 : 1995 + Corr 1995)DIN EN 60068-2-27 Basic environmental testing procedures Part 2: Tests Test Ea and guidance: Shock(IEC 68-2-27 : 1

11、987)DIN EN 60529 Degrees of protection provided by enclosures (IP code) (IEC 60529 : 1989 + A1 : 1999)DIN EN 60825-1 Safety of laser products Part 1: Equipment classification, requirements and users guide(IEC 60825-1 : 1993)DIN EN 61326 Electrical equipment for measurement, control and laboratory us

12、e EMC requirements(IEC 61326-1 : 1997 + IEC 61326-1/A1 : 1998 + IEC 61326-1/A2 : 2000)DIN EN ISO 4288 GPS Surface texture: Profile method Rules and procedures for the assessment ofsurface texture (ISO 4288 : 1996)DIN EN ISO 11145 Optics and optical instruments Lasers and laser-related equipment Term

13、inology,symbols and units of measure for the specification and testing of lasers and laser assem-blies (ISO 11145 : 1994)International vocabulary of basic and general terms in metrology (VIM)1)3 ConceptsFor the purposes of this standard, the concepts defined below apply, in addition to those defined

14、 in DIN 1319-1to DIN 1319-3, DIN EN ISO 11145, and the International vocabulary of basic and general terms in metrology(VIM).3.1 General concepts3.1.1 Optoelectronic measuring systemMeasuring system consisting of a light source, sensor, signal processor and controller.NOTE: The optical system may co

15、nsist of several physically separated units (e.g. a sensor and controllerconnected by a cable).3.1.2 Light sourceAll components required to produce the necessary beam pattern for the relevant procedure and measuringrange.EXAMPLES: Laser source, laser optics, shutters, grids, mirror scanners, laser d

16、iode controllers.3.1.3 Beam patternThe distribution of the radiation produced by a light source over time and space within the measuring range.EXAMPLES: Measuring spot, arrangement of measuring spots in a line, measuring line.3.1.4 Signal processorAll components needed to process the measured signal

17、s, giving the measurand and producing the results.EXAMPLES: Linearisation module, receiver electronics for sensor, filters.3.1.5 ControllerAll components needed to control an optoelectronic system and communicate with external systems or de-vices.EXAMPLES: Microcontroller, data storage unit, digital

18、 input/output, interfaces.3.1.6 Incident beamThat part of the beam which is reflected off the test object surface, then detected by the photodetector in thesensor and imaged on the receiver.3.1.7 Dynamic range of incident beamRange of radiant power of incident beam within which specifications are fu

19、lfilled.1) Obtainable from Beuth Verlag GmbH, Burggrafenstrae 6, 10787 Berlin, Germany.Page 3DIN 32877 : 2000-083.1.8 Limit of irradianceMaximum value of the irradiance due to ambient light at which the limits of error specified for the system arenot exceeded.3.1.9 Measuring frequencyFrequency of th

20、e updated measured value at the system output.3.1.10 Maximum trigger frequencyFrequency at which the measured value can be updated by means of an external trigger signal at the systemoutput.3.1.11 Cut-off frequency for change in measurandFrequency up to which a sinusoidal change in the measurand can

21、 be transmitted without the limits of error beingexceeded.3.1.12 Trigger delayThe delay between the time the trigger signal is produced and the subsequent start of the measurement.3.1.13 Response delayThe delay between the time the trigger signal is produced and the output of the measured value.3.2

22、Concepts related to triangulation and focus methods3.2.1 Measuring spotIrradiation which is produced by the light source and is focused on the surface of the test object.3.2.2 Centre distanceDistance between the reference plane of the sensor and the centre of its measuring range (see figures 1 and 2

23、).3.2.3 Cut-off frequency for change in incident beamFrequency up to which the limits of error are not exceeded for a constant measurand and a change in the incidentbeam equal to 95 % of the dynamic range.3.2.4 Jump response at interfaceTime passing between the first change in the measured value by

24、10 % of the value obtained on one side of thetransition zone of the cylinder (see subclause 6.3.7) when it is at rest, and the point in time at which a measuredvalue which differs by 10 % from this value at rest is obtained on the other side of the transition zone.3.2.5 Cut-off angleMaximum angle be

25、tween the averaged normal to the test object surface and the incident beam at which thelimits of error are not exceeded.3.2.6 RepeatabilityAbility of a measuring instrument to provide closely similar indications for repeated applications of the samemeasurand under the same conditions of measurement

26、(from VIM, 5.27).3.2.7 Temporal repeatability (triangulation method)Repeatability of results obtained under repeatability conditions where the position of the measuring spot on thetest object does not change.3.2.8 Spatial repeatability (triangulation method)Repeatability of results obtained under re

27、peatability conditions where only the lateral position of the measuringspot on the test object changes, but not the distance between the test object and the reference plane of thesensor.3.2.9 Linearity error (triangulation method)Deviation of the measured value from the true value where the effects

28、of temporal and spatial repeatability arereduced by averaging.3.3 Concepts related to shadowgraph and laser scanning methods3.3.1 Working distanceDistance between the sensor and the test object measuring surface.Page 4DIN 32877 : 2000-083.3.2 Measuring distanceDistance between the light source and t

29、he surface of the test object.3.3.3 Scanning widthThe width of the beam used to evaluate results (in shadowgraph method), or the diameter of the beam measuredat the point where the beam is perpendicular to the lens system (in laser scanning).4 Principle of methods4.1 GeneralThe methods described her

30、e are non-contact methods. The measurement signal is registered and processedeither as a digital or analogue signal, producing either a digital or analogue result.4.2 Triangulation and focus methodsWith the triangulation method a beam is directed at the test object surface, producing a measuring spo

31、t. Partof the back-scattered radiation is imaged in a predetermined direction on a receiver, producing a signalcharacterizing the current position of the measuring spot within the measuring range. This signal thus is ameasure of the distance between the spot and a defined reference plane on the sens

32、or, or in the case of multi-dimensional measurements, the distance between the spot and a reference coordinate system. Annex A de-scribes multi-dimensional triangulation measurement.NOTE 1: For test objects having an optically smooth or reflective surface, the received light may not besufficient for

33、 building a measurement signal. Depending on the objects geometry, scattering and vignettingmay occur, which can have an effect on the measured result. These secondary reflections occur primarilyin measurements of inside edges and should be taken into consideration in the evaluation and presentation

34、of results.NOTE 2: The size or shape of the spot can change within the measuring range. Causes for this includea) characteristics of the light source (e.g. focusing optics);b) geometric or optical characteristics of the test object surface (e.g. inclination, volumetric scattering);c) characteristics

35、 of the transmission medium (e.g. ambient atmosphere).With static triangulation, the position of the spot image on the receiver is used to determine distance. There areno moving components. The basic principle of static triangulation is shown in figure 1.Figure 1: Principle of static triangulation11

36、 Light source12 Beam formation optics13 Centre distance14 Measuring beam15 Centre of measuring range16 Triangulation angle at centre distance17 Diffuse reflection18 Receiver19 Imaging optics10 Reference plane11 Incident beam12 End of measuring range13 Measuring range14 Beginning of measuring range15

37、 Test objectPage 5DIN 32877 : 2000-08Static triangulation can be supplemented by the use of multiple receivers, a moving beam or moving receiveroptics.Triangulation is normally used for measurements with a span of 1 mm to 100 mm on a diffuse reflective surface.With the focus method a collimated ligh

38、t beam is projected onto the surface of the test object. The optics canbe moved and continuously tracked so that the focus of the beam is always on the test object surface (seefigure 2). The displacement of the optics is measured, giving the distance between the sensor and the testobject.The focus m

39、ethod is normally used where the span is smaller than 1 mm. Because the spot diameter is about1 m, the surface roughness of the test object has an influence on test results.1 Light source 17 Movable optics2 Beam splitter 18 Centre distance3 Receiver 19 Measuring range4 Graduated scale for distance m

40、easurement 10 Test object5 Sensor 11 Beam angle6 Stationary opticsFigure 2: Principle of focus method4.3 Shadowgraph methodWith the shadowgraph method (as shown in figure 3), either the shadow of the test object is registered by thereceiver (diode array or photodetector), or the difference between l

41、ight and dark at the edges of the object areimaged on the receiver by means of an optical system. The length of the shadow corresponds to the objectdimensions. Either parallel or non-parallel light can be used.A variant of the shadowgraph method is laser scanning. Here a collimated beam (e.g. laser

42、beam) is projectedat a rotating mirror which then directs the beam through an optical system parallel to the laser source (seefigure 4). A second optical system focuses the beam onto a receiver, which converts the beam into an electronicsignal. The duration of the interruption, determined by the ang

43、le of rotation of the mirror, gives the dimensionsof the test object.Page 6DIN 32877 : 2000-081 Light source 6 Measurement plane2 Test object 7 Sensor3 Parallel light 8 Measuring distance4 Imaging optics 9 Working distance5 ReceiverFigure 3: Principle of shadowgraph method with parallel light5 Requi

44、rementsDepending on the measurement method used, the manufacturer is to provide the technical data and measuringequipment parameters listed in table 1. Additional information may be provided. Verification of the parameterswhich influence uncertainty of measurement is to be carried out as specified i

45、n clause 6.1 Light source 17 Lens2 Test object 18 Mirror3 Laser 19 Measuring distance4 Imaging optics 10 Sensor5 Receiver 11 Measurement plane6 Motor 12 Working distanceFigure 4: Principle of scanning methodPage 7DIN 32877 : 2000-08Table 1: Measuring system parametersNo. Parameter Unit Remarks1 Meth

46、od of measurement 2 Measuring range/span mm 3 Centre distance mm 4 Working distance mm 5 Limits of error m See DIN 1319-1.6 Linearity error for measuring range % See subclause 6.4.2 for verification.7 Repeatability temporal m spatial mExpressed as repeatability standard de-viation or repeatability l

47、imit (as inDIN 55350-13).8 Cut-off angle Orientation of sensor is to be given.Cut-off frequency for change in measurand9 change in incident beamHz May also be expressed as jump response.10 Measuring frequency Hz, kHz 11 Maximum trigger frequency Hz 12 Trigger delay s 13 Scatter of trigger delay s 14

48、 Response delay ms 15 Relevant information on laser source See DIN EN 60825-1.16 Characteristic dimensions of beam pattern atbeginning, middle and end of measuring range For 1D triangulation (e.g. the diameter ofmeasuring beam, or for elliptical beams,length of both semi-axes).17 Position of beam re

49、ferred to sensor coordi-nates To be expressed, for example, as diame-ter of enveloping cylinder or angle.18 Stability of measuring spot position , mm Give angle and lateral deviation fromcentre of measuring range.19 Limit of irradiance due to ambient light at im-aging optic planemW/mm2Detailed information on spectrum andspatial distribution, as well as details overtime may be necessary.20 Warm-up time min 21 Temperature coefficient m/C 22 Data output Give information on interface.Controller Trigger input E.g. opto-