`
`EXHIBIT
`1003
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`1003
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`3,533,702
`F, HocK ETAL
`Oct. 13, 1970
`MULTI-PURPOSE OPTICAL MEASURING DEVICE FOR DETERMINING
`THE POSITION OF AN OBJECT IN TWO COORDINATES
`Filed April 19, 1966
`2 Sheets-Sheet 1
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`Fig. I
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`UTILIZATION
`MEANS
`IM
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`IN VENTOR
`FROMUND HOCK, KARL LANG, HERIBERT LIYISSEM
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`3,533,702
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`F. HocK, ETAL
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`I
`Oct. 13, 1970
`MULTI-PURPOSE OPTICAL MEASURING DEVICE FOB DETERMINING
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`1 THE POSITION OF AN OBJECT IN TWO COORDIMTES' v
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`Filed April 19, 1966-
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`2 Sheets-Sheet 2
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`7
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`FROMUND HOCKY
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`INVENTOR ‘
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`'
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`q
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`.,
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`-.'KARL“LANG
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`HERIBERT" LUESSEM
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`I
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`ATTORNEY
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`United States Patent 0"
`too
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`3,533,702
`Patented Oct. 13, 1970
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`1
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`3,533,702
`MULTI-I’URPOSE OPTICAL MEASURING DEVICE
`FOR DETERMINING THE POSITION OF AN OB
`JECT IN TWO COORDINATES
`Fromund Hock, Wetzlar, Karl Lang, Atzbach, Kreis
`Wetzlar, and Heribert Liissem, Braunfels, Kreis Wetz
`lar, Germany, assignors to Fa. Ernst Leitz G.m.b.H.
`Filed Apr. 19, 1966, Ser. No. 543,575
`Claims priority, application Germany, Apr. 24, 1965,
`L 50,566; Aug. 18, 1965, L 51,411
`Int. Cl. G01b 11/00
`U.S. Cl. 356-—167
`
`13 Claims
`
`ABSTRACT OF THE DISCLOSURE
`An optical measuring device which scans images of two
`oblong illuminated scanning marks along non-parallel
`paths on an object/to be located or positioned, each
`mark being scanned parallel to itself. The images are re
`?ected from the object onto an index carrier having inter
`secting index lines parallel to the re?ected images of the
`scanning marks. Signals resulting from the modulation of
`the scanning marks by passing over the index lines are
`utilized to measure the position of the object with respect
`to the device, or to operate servo means for positioning the
`object.
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`BACKGROUND OF THE INVENTION
`This invention relates to a multi-purpose optical meas
`uring device for determining the position or the move
`ment of an object in two coordinate directions simul
`taneously.
`DESCRIPTION OF THE PRIOR ART
`In the prior art there are a number of measuring de
`vices for determining the position of a reference mark
`place on an object to be positioned, e.g., the carriage
`of a machine tool. These instruments make use of a
`beam of light which is caused to oscillate by means of
`a de?ector and impinges on a reference mark, such as a
`scale graduation. The error signal for control of a posi
`tion servo is obtained by comparison of the different
`times which elapse between the respective crossings of
`the reference mark. An example of such a device is shown
`and described in my US. Pat. No. 3,254,227. A disad
`vantage of these instruments is that they can only be
`used to determine position along one of the two coordi
`nate axes of the plane perpendicular to the optical axis of
`the device.
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`SUMMARY OF THE INVENTION
`
`Accordingly it is an object of the invention to provide
`a multi-purpose optical measuring instrument which can
`readily be adapted by one having ordinary skill in the art
`to the determination of the position or the movement of
`an object in two coordinate axes of a plane perpendicu
`lar to the instrument’s axis, for the determination of the
`angle of objects inclined to the instrument’s axis7 for the
`measuring of curvature, and for the determination of the
`eccentricity of revolving shafts in two coordinates.
`Brie?y, the subject matter of the present invention com
`prises a mnlti-purpise optical measuring device for visual
`and/or photoelectric determination of the position of
`measuring marks relative to two coordinate axes in one
`plane. The device is characterized in that at least two
`oblong scanning marks (e.g., optical slits or mirrors)
`are provided which are not parallel to each other. The
`light transmitted from these marks, or elongated light
`transmitting means, passes through an optical system com
`prising at least one objective and one *beam splitter and,
`after re?ection from the object to be measured or from
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`a re?ector which cooperates with said object, and after
`passing again through said objective and said beam split—
`ter, is projected upon an index carrier. The indices of that
`carrier consist of intersecting lines which run parallel to
`the images of the scanning marks. Means are also pro
`vided for the separation of signals corresponding to the
`measurements in the two coordinate directions, those
`means are placed adjacent to the index carrier in the di
`rection of the impinging light for the evaluation of the
`measuring result. The identi?cation of the portion of the
`optical output signal corresponding to one or the other of
`said scanning marks may be achieved in different ways.
`For instance, it is possible to move the scanning marks
`with a different frequency than that with which the in
`dex carrier is moved. However, it is also possible to
`distinguish between said portions 'by using polarizing
`means or dilferent colors. According to one embodiment
`of the invention the scanning marks may be placed in such
`a way that one of them extends parallel to the direction
`of their movement. In this case the movement of the in
`dex carrier will be performed in the direction of the
`image of the other mark.
`vIt is further possible to place the scanning marks, or
`elongated light transmitting means, in such a way that
`the direction of movement of the scanning diaphragm is
`parallel to the bisecting line of the angle subtended by
`the marks. In one special embodiment the scanning marks,
`or elongated light transmitting means, consist of two nar
`row mirrors, each one rotatable in its plane independently
`from the other, which lie close together and are illumi
`nated. The corresponding index carrier consists of two
`discs provided with lines for indices. The discs are placed
`close to each other in the direction of light travel and are
`pivotably mounted. Adjusting means serve to transmit any
`rotational movement of the carriers of the scanning
`marks in a synchronous manner to the index carrier. This
`device makes it possible to adjust the instrument over a
`wide range, of angles between the two measuring co
`ordinates.
`DESCRIPTION OF THE DRAWING
`The manner in which the invention may be carried out
`will now be explained with reference to the attached
`drawings by way of different forms of embodiment. In the
`drawings
`FIG. 1 shows a device in which the coordinates of
`measurement subtend a ?xed angle,
`FIG. 1a is a perspective view of an embodiment of
`a detail of FIG. 1.
`FIG. 2 shows a device in which the coordinates of
`measurement subtend a variable angle,
`DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`In FIG. 1 a light source 10 illuminates via a condensor
`11 a movable diaphragm 12 provided with an aperture
`112 serving as a scanning mark. The scanning mark aper
`ture 112 consists of two slotlike apertures 112a and 11212
`which are inclined to each other by 90°. The diaphragm
`is operated by a driving unit 111 to oscillate with a
`frequency h in the direction of the scanning mark aper
`ture 11212. The light rays emerging from the luminous
`scanning mark aperture 112 of the diaphragm pass via a
`beam splitter 13 and an objective 14 onto a re?ector 100
`which by way of example has the shape of a sphere
`and has a re?ective coating on its outside. As pointed out
`hereinabove, many re?ector arrangements may be pro
`vided for use with the device of the present invention by
`those having ordinary skill in the art and knowledge of
`the present disclosure. The sphere is positioned so that
`its center 100' coincides with the image plane of objec
`tive 14. Rays re?ected from the surface of this sphere
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`3,533,702
`travel backwards through objective 14 and, via the beam
`thereon cannot be made perpendicular to the planes of
`splitter 13, project images of the scanning mark apertures
`mirrors 204 and 205, nor nearly so. The carriers of the
`scanning marks as well as the carriers of the indices are
`112a, 1121) on an index carrier 16 which is provided with
`mounted in set-rings 215, 216 and 217, 218 respectively
`the indices 115a, 115k. For these indices, lines are used
`which are provided with a scale. The latter can be used
`which intersect at the same angle as the scanning mark
`to adjust the scanning marks and the indices to the same
`apertures 112a, 1121). The index carrier is movable in the
`angle.
`direction of the indices 115a. It oscillates with a frequency
`Adjacent to the index carrier in the direction of the light
`f2 which is dilferent from the frequency f1 and has no
`a beam splitter 210 is placed which permits observation of
`higher harmonic wave in common with frequency h. To
`the result of the measurement by means of an eyepiece
`this end the index carrier is provided with a driving unit
`211 and at the same time permits the registering of the
`110. The image of the index plane of carrier 16 is ob
`result of the measurement photoelectrically. To this end
`served by means of an eyepiece 18 and ‘by means of an
`a prism 221 is arranged next to the beam splitter 210 in
`other beam splitter 17. It may also be passed on to a
`the direction of emerging .light; said prism separates the
`photoelectric transducer 19 to the output terminals of
`measuring signals according to their color and transmits
`which two evaluation devices such as tuned ampli?ers
`the signals originating at the scanning mark 204 to a
`113, 114 are connected; one of these evaluation devices
`photoelectric transducer 212 While at the same time it
`reacts to a signal of frequency (2n+1)f1, whereas the
`transmits the signals originating at the scanning mark
`other one reacts to a signal of frequency (2n+1)j‘2.
`205 to a photoelectric transducer 213. Of the signals ob
`The operation of this embodiment is as follows:
`tained in this way from the photoelectric transducer use
`A lateral displacement with respect to the axis of op
`20
`is made in utilization means which are known in the art
`tical elements 11, 13 and 14 of the sphere center 100
`and for this reason need not be described in detail.
`causes the image of the scanning mark to be also laterally
`From the embodiments described it will be readily un
`displaced and the image appears displaced on the index
`derstood how a separation of the signals originating at the
`carrier 16 in accordance with the power of the objective
`respective scanning marks may be achieved by using light
`14. Since aperture 112a is perpendicular to the indices
`of different colors. Such a separation, however, may also
`11511, the oscillation of the diaphragm 12 produces no
`be achieved by using different frequencies of alternating
`light modulation at the index carrier 16 by interaction
`intensity or by polarisation of the light coming from the
`with indices 1151). The image of the scanning mark aper
`scanning marks.
`ture 112a will, however, be modulated by the indices
`Since certain changes may be made in the above con
`11511 at the frequency ]‘1 and its harmonics. Modulation
`of the light originating from the scanning mark aperture
`structions without departing from the scope of the inven
`tion, it is to be understood that all matter contained in
`‘1121; at frequency f2 and its harmonics is caused by the
`the above description or shown in the accompanying draw
`indices 11512 when index carrier 16 oscillates in the indi
`ings is to be interpreted as illustrative, and not in a limit
`cated direction at a frequency f2.
`ing sense.
`For a scanning mark a luminous element may be used,
`It is to be understood that the following claims are in
`the radiation from which is not thermally stimulated.
`tended to cover all of the generic and speci?c features of
`To this end, a luminous semi-conductor may be used
`the invention herein described, and all statements of the
`which has two inclined PN-junctions which may either
`be cyclically moved either synchronously or independently
`scope of the invention which, as a matter of language,
`might be said to fall therebetween.
`from each other. The slots 112a, 11% and the elements
`What we claim is:
`10 and 11 of FIG. 1 are substituted here by the PN
`1. A multi-purpose optical measuring device for deter
`luminous semiconductors 1120, 112d mounted on a
`mining the position of an object in two coordinate direc
`plate 12’.
`tions, comprising: a plurality of means acting as light
`FIG. 2 shows an instrument with a slightly different
`sources transmitting a constant light ?ux and having at
`construction which may be used for measurement along
`least two thin elongated, non-parallel, cyclically moving
`coordinates subtending a selectable angle. A light source
`201 illuminates the scanning marks via a polariser 200,
`light transmitting means; at least two index means; a mov
`able carrier means, carrying said index means, each of
`condensor 202, a beam splitter 203 with a quarter wave
`plate 203'. The beam splitting plane of the beam splitter
`said index means corresponding to one of said light trans
`mitting means; an optical system comprising a ?rst beam
`is designed as a polariser. The scanning 'marks 204, 205
`splitter and an objective lens, said optical system ‘directing
`consist of narrow mirrors which are rotatable in their
`light transmitted by said light transmitting means onto
`own planes and placed as closely together as possible in
`said object and directing light re?ected from said object
`the direction of the light. They have different re?ecting
`qualities with regard to color (red and green). They are
`onto said index carrier means, the light thus directed
`from each of said light transmitting means to its corre
`oscillated in unison in the direction of the arrow by
`sponding index means cooperating with the correspond
`means not shown. The narrow mirrors serve as scanning
`ing index means to produce modulated light signals, means
`marks and rays re?ected from them pass through quarter
`for detecting said modulated light signals and means for
`Wave plate 203', beam splitter 203, another quarter plate
`producing from said detected modulated light signals elec
`20 " and objective 206 on to the re?ector 207. This re?ec
`trical signals which are a function of the position of said
`tor is provided with two ?elds of lines 207', 207", and
`object in each of said coordinate directions; separating
`each one of which lies in the direction of a measuring
`means for separating said electrical signals into at least
`coordinate and parallel to a scanning mark image.
`two signals each corresponding to one of said transmitting
`Re?ector 207 may be an object to be positioned
`means respectively; and utilization means for utilizing the
`or located by the device of the invention, or an auxiliary
`separated signals.
`device adhered thereto either temporarily or permanently.
`2. A measuring device as claimed in claim 1 including
`Index lines 207', 207" cause a modulation of the im
`means for selecting the coordinate directions de?ned by
`pinging light rays. The modulated light rays re?ected from
`said light transmitting means at the will of the operator.
`the surface of this re?ector travel backwards through the
`3. A measuring device as claimed in claim '1 in which
`elements 206, 203", 203 and project the images of the
`said light transmitting means comprise semiconductor
`scanning marks on an index carrier 220. This index carrier
`elements including light transmitting PN-junctions.
`is formed by two transparent discs; each one has a ?eld of
`4. A measuring device as claimed in claim 1 in which
`lines 208 and 209 respectively and both are mounted in
`said light transmitting means are jointly cyclically moved
`dependently and pivotably as close together as possible
`in a direction perpendicular to the major dimension of
`with the line bearing sides facing each other.
`one of them, and said carrier means is cyclically moved in
`Each disc is arranged in such a way that the lines
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`3,533,702
`11. A measuring device as claimed in claim 10‘ com
`a direction perpendicular to the major dimension of the
`prising optical means mounted in the way of the partial
`other one of them.
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`light beam ‘for visually observing the position of said
`5. A measuring device as claimed in claim '1 in which
`object in the coordinate system of said index means.
`said light transmitting means are jointly cyclically moved
`12. A measuring device as claimed in claim 1, said
`along a line bisecting the angle between the major dimen
`beam splitter and objective interposed underneath said
`sions of said light transmitting means.
`light transmitting means in initial position in axial align
`'6. A measuring device as claimed in claim 1 in‘ which
`ment with said light transmitting means and said object,
`said light transmitting means comprise narrow mirrors
`said beam splitter having means to split a beam of light
`placed close together and rotatably mounted in their re
`into a ?rst light beam directed toward said object and to
`spective planes, said carrier means comprises two trans
`send the light beams returned from the object inclined to
`parent discs having light obstruent lines for index means,
`said discs being placed close together and being rotatably
`said ?rst light beam.
`13. A measuring device as claimed in claim '12, further
`mounted, and means for synchronous adjustment of said
`comprising a second beam splitter generating a visual
`mirrors and said transparent discs.
`beam in alignment with said ?rst beam splitter’s second
`7. A measuring device as claimed in claim 1, said light
`light beam, said second beam splitter further generating‘
`transmitting means comprising a source of light and a
`diaphragm, said diaphragm having coplanar slots, said
`an optical beam inclined to said visual beam.
`coplanar slots being two divergent intersecting slots; said
`diaphragm in an inoperative ready to start position being
`interposed in axial alignment between said source of
`light and said beam splitter.
`I8. A measuring device as claimed in claim 7, and a
`condensing lens interposed between said source of light
`and said diaphragm in said axial alignment.
`9. A measuring device as claimed in claim 1, said ob
`ject being a mirror.
`10. A measuring device as claimed in claim 1, further
`comprising a second beam splitter mounted in alignment
`with said index means, said second beam splitter being
`adapted to split the light beam re?ected by the object into
`a ?rst partial beam for visual observation and a second
`partial beam for photoelectric scanning.
`'
`
`References Cited
`UNITED STATES PATENTS
`2,775,158 12/ 1956 Mitchell __________ __> 350“--1O
`3,322,953
`5/ 1967 Zuckerbraun ______ __ 2‘50—235
`FOREIGN PATENTS
`l/1948 Sweden.
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`125,912
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`RONALD L. WIBERT, Primary Examiner
`J. ROTHENBERG, Assistant Examiner
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`250—237; 356—169
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`US. Cl. X.R.