Патент USA US2404302код для вставки
July>16y1946~ E. H. LAND ¿TAL 2,404,302A RANGE FINDER Filed April 22,1943- _ » ¿im)y BY ' ' INVENTORS. m i Patented July 16, 1946 2,404,302 UNITEDJ STATES PATENT 2,404,302 RANGE FINDER Edwin H.' Land, Cambridge, Mass., and> Dexter P:` Cooper, Jr., Washington, D.` C., assig'nors` to. Polaroid Corporation, Cambridge, Mass., acor poration. of. Delaware Application April 22, 1943, Serial No. 484,005 (Cl'. 88-226lî 5`. Claims. 1 ~ A 2 drawing, housing lo of. .any desired size and shape isprovided» with. a pair ot mirrors orv other This invention relates to a new and improved range iinderand reticles, therefor.4 ~ reiiecting surfaces L2 adapted _to receiveV light It is; one object of the invention te provide. a range- finder comprising means for impressing from in front of the instrumentthrough. thawin optical, indicia~ the field'l oí View at-a prede termined apparent distance from the-instrument and therebyY de.tern'iiningy the distance of objects both. to providean effectively enlarged interocular distance or increased sterecscopieeiîect, Vand also dows or apertures atl 4. This arrangement serves ’ to limitthe- ñ'eld oí view to an- area substantially Another obiectl is to provide a range. ñnder of the above characteristics. wherein a. plural ity of optical indicia aree impressed upon the in front of thel instrument. Associated with, mir 11ers. l1 isa. pair of transparentmirrors l5 each> of ñeld of viewp each at predetermined~ different ap- . mirrors t2 and t@` reñectittowards one of eye. in; said field from thev observer. e which4 is adapted to Vreceive light from one of parent distances> from»` the instrument. pieces I6.. stereoscopic image»y or images: of optical, indicia with the. result thathis right eye will receive lig-ht from right-hand. mirrorsV L?. and. 1.5„ andhisÃleft eye. will .simultaneously receive light fromleft Anobserver employing this range ñnde'r'will A further object. is. to prov-ide, a range finder of; the above characteristics; wherein thev desired 15 look simultaneously throughboth of eyepieces i6 are produced4 byY meansoi one or more pairs of light-polarizing indicia- elements, marks or. the hand. mirrors L2. and l5.AV Itis to be understood combination. with» means for. collimating the light 20 that mirrorsy li and mirrors l2 should he soposi tioned- *as td enable. an Aobserver employing the traversing said indicia elements, and means for instrument’to see.. substantially the same field insuring: that each. eye of the observer see only with .eacn eye.v Suchfajstructura. except fior the one image» in. each of» said pairs. ~ use ot transparent. mirrors l5 instead of wholly A. still further object is to provide. a new reti cle-adapted for. use in- a, range finder of theV above 25. reflecting surfaces, is. standard inthe construc tion of, range finders. of the. class ofl the present characteristics and comprising a stereoscopic inventiom Its. effect and; purpose is to increase light-polarizing'printhaving oneor more pairs of the. effective. interocul'ar Adistance of the observer right-eye and left-eye polarizing indicia elements, to thedi'stance between mirrors l2., and thus.` to marks. or the like, of. kopposite polarization char like, of opposite polarization characteristics in acteristics, the indicia elements `comprising each of, saidY pairs being positionedat >predeterminedly differentl distances apa-rt in order thatan observer ai increase considerably the. stereoscopic acuity of. his vision as applied. to the field. The indicia-forming apparatus of. this embodi.- ` ment .of the invention is illustrated. in detailin o may fuse» them to. form» a. series ofi stereoscopic Figs. 2 and 3,` and may conveniently be located images, each of. which will appear to lie at a fr: Llo within an extended portion [8 of housing l0.` It _ different distance from- the observer. Other objects and advantages willV in part to be apparent and inA part be pointed out in the course of thev follow-ing- description of one or ' more» embodiments `of the invention, which are given as non-limiting examples,4 in connection with the» accompanying drawing, in which; Figure 1 is aV plan. view oft a housing suitable for a range iinder constituting an' embodiment> of the invention.; Fig. 2 illustrates diagrammatieally and in plan the optical elements employed4 in one embodi ment of~ the invention; . ' comprises a reticle. 2_0L of particular characteristics - to be .described in detail hereinafter, alight source 2'2- of any desired typeÄ and a relatively large. lens 24,01' other device for collimating the rays ema nating from source 22 andl traversing reticle 20. The terrnfreticle.” as. it is used herein and in . the claims is to, be understood as` having. the meaning. commonly accorded` thereto in. the range finder art., and it isi-._Q bey considered as. including any means' in the optical system of. the instru " ment for' producing visible indicia such, ,for ex ample, as a line., a dot or acircle. or otherfigure. In the preferred embodiment, of the present Fig. 3 is an enlargedV diagrammatic view illus trating a stereoscopic, light-polarizing printsuit invention, reticle 20 comprises alight-polarizing able for> use asy a reticle in the range finder of stereoscopic print of the. type. shown and de- Y the invention; and. Fig. ‘iv is aside- view, similar to Fig. 2,v illus scribed in Patent. No„ 2,203,687.. More. specifical trating diagrammatieally a. modification of the plastic material having reproduced4 thereon 'by invention. meansof. light-polarizing. areas a series. of stereo » 1y, it. may comprise a sheet .25- of a transparent In the formy of the invention illustrated in the 55 scopiß pairs of images comprising right-eye im 2,404,302 Y 4 nearer lens 24 than the focal pla-ne of the lens, the series of reticle images will appear to lie ages, indicia elements, marks or the like, A, B, C, D, having their transmission axes parallel, for example, to arrow26, and left-eye images, indicia elements, marks or the like, A', B', C', D', having in the field nearer to the instrument .than when the reticle is Within the focal plane 0f the lens. All such modifications embody the essentials of the invention, and are accordingly to be con their transmission axes at right angles to arrow 26, as represented by arrow 28.V _ yA suitable material for use as the base sheet in. Y producing reticle 20 is polyvinyl galcohol, and in one embodiment of the invention reticle 20 may comprise a sheetl 25 of said material having strued as coming, within the sGODe thereof. f It will'now be apparentthat inïiall cases the range finder of the invention will be so cali« brated that the series of reticle marks will ap the molecules on one surface thereof oriented 'j n'fpear to lie at known distances from the in parallelto arrow 25 and themolecules onY the i. strument. An observer using the device may therefore compute .the approximate distance’of other surface thereof oriented parallel'to arrow 2li. Alternatively, reticle ZO‘may/comprise a com-< , objects in the field b’y their relation in space posite sheet 25 formed by bonding two mólecu ' . tothe apparent positions of the images. larly oriented layers of polyvinyl alcohol ltogether ’ It will f be apparent,V furthermore, that the invention Y with their directions of molecular orientationrel-- ,-. ` vcontemplates the employment of any useful num atively perpendicular. Such a sheet is shown andI , ber of reticle images, although the essential re described, for example, in U. S. Patent No. 2,289, '115. Images A, B, C, etc. maybe produced by quirements thereof are fulfilled if only a single 20 dyeing or staining the molecularly oriented sur stereoscopic pair of images, for example CC', isu'se'd. faces of' the :polyvinyl alcohol'sheet'fwith a suit able ldiehi‘oie dye or stain, suchïfor example asa ' f " ~ - - " ' It Ashould be >understood that indicia elements,Y marks or the? like, A, B, C‘, etc.- in f‘ reticle 20 may take any ofymany forms;V For exampla'lríy r solutionf off'iodine- andl an iodide. Y thefoperation 1of the invention,V >reticle 20 a' preferred case said indicia elements may com-' prise Ynon-polarizing .light-transmitting outlines in an> otherwise uniformly light-polarizing sheet, is „ positioned substantially ,in the'focal plane ofY lens Y21|,”and elements 3l] >comprise polariz ers arranged sothat each eye Yof the observer will see, onlynitsrproperv set of the images of and in this case ¿said indicia elements will ap pearas outlines of light superimposedupon the ñeld. Another example mayv comprise 4the con-verse of~this case, with said indicia elements ` reticle 20. Y Thus, right-eye polarizer 30 may have its V‘axis parallel to arrow 28 and left-eye po larizer may have its Vaxis parallel to arrow 26. ' >When reticle/20 is viewed through eye-pieces formed as light-polarizing outlines in an other wise non-polarizing light-transmitting sheet,VV and ' -|6 and, polarizers 431)„ the observer will see only inthis case said'indicia elements will appear as a single set'- of rstereos_co’pic images AA', BB', CC',vand DD', each of whichwill appear to black outlines Vsuperimposed upon the ñeld. In either of said examples, each of said indicia lie atja different vertical' plane in> space ow elements may comprise a' solid areaV rather- than in_g .tothevarious .amounts by' which the com-j.l ponent images of thestereoscopicpairsare lat-' erally'oñ‘set. The elements ¿of stereoscopic pair apparent to those skilled in the art, and are f AA' areV illustrated. as >being substantiallyv su perimposedfand thestereoscop-ic image formed ~ therebywill Vvappear to lie farthest fromjthe ob an- outline." Still further alternatives will be 40 tobe Yunderstood asi coming within the scope h_erœóf’v~ , v. _, ì . .Y Aireticle of the _type 4shown in Fig. 3 is par ticularly useful with‘moving _targets or when the range finder itselfv is moving towards the tar servermwhile stereoscopicimage DD' lwill ap pear nearest 'to the observer, CC_"the next, and 45 get. V"For example, it may be assumed that a range finder using reticle 20 is installed kin' a BB' farthest awayjwith the exception of AA'. tank or airplane approaching a target and that 1 It will be understood thatthe relative 'lateral it is desiredtohold _ñre until the rangeV is,y for displacement .of Athe two indicia elements form example,i200 yards.Y /In Ythis case, indicia ele-l ingjeach of the stereoscopic pairs in reticle 20 will besuch that the stereoscopic images formed 50 ments D and D'vvillY initiallyrbe so oiîsetrwith thereby will appear to lie'at known distances ` respect to eachother that the range of thef'api parentposition of the stereoscopic image formed fromïthe instrument._ 'Said distances may ‘in therebywill be 200 yards. Similarly, the stereo-A turnbe determined in a variety of ways. If, scopic image CC' may appear to lie at 300 yards ,for'exampla mirrors I5 are at right angles to each. other and parallel to their `associated mir 65 and the stereoscopic image'lBB' may appear to rors.v l2,»reticle image AA' will appear to lie atfinñnity with respect to space, with reticle images BB', CC' and DD' progressively nearer the instrument in_theV ñeld. If, however; mir lie at 400 yards. , Therefore, as the tank'or plane _ approaches the ' target, the gunner will know that he should ‘prepare to fire when- theï ap-` parent position of ima-ge BB' ¿coincides with the rors Vl5 are Vat right angles to eachother and 60 target, should aim when the apparent position of image CC' 'coincides Áwith the target," and mirrors `>I2 are atan angle of lessV than„90 de should fire when the `'apparent'positionY of im greestoeach other, or vice versa, reticle image age DD' coincides with the target. It is par AA’„wil1 ,appearv to Alie nearerrin _space than in# ticularly useful, for example, in an'airplane to utilize only a single stereoscopic pair of indicia spondingly nearer. í'I'he-y actuall ranges of said elements in reticle 20 whoseapparent position apparentjpositions will> be dependent in each will _lie at the known' range which is the maxi-v caseupon the,V b‘ase line Aof the device, i. e. the mum for accurate ñre for the weapons in con distance ‘between mirrors I2. ' ' ¿Although it ‘is _, preferred to place reticle' 201 , . nection with the range ñnder being used. , ' substantially within the focal plane of lens Y2t, 70 It will be understood that the above-described this arrangement ~is not essential, and it is pos embodiment of the invention is given only by ,sible- to `obtain further variation of the rela'-> tionship between the reticle images and the iìeld by changing'.V therelative positions of reticle 20 ' and lens 24. If', for eXample, reticleíZll, is slightly way ,ofv illustration, and that it maybe modified ' to a considerable degree without departing from within vthe scope of theinvention. VTo'afconsid erable extent the construction of the range find m4043302 6 5 ers: of the» inventiony is `»determined' by the lpurpose for which they are intended-_> 'For example, `mir rors A I 2‘ andir Hiv are .usedl asl illustratedi in Figs.> 1 andE 2'1 for the purpose ofvincreasing the range of the'l instrument »and its accuracy at vincreased ranges. However, thisV construction may be mod ified if the instrument is designed for use at rela tively shorter' rang-es,> il e. ofthe order of 100 yards or less. Fer'such-short ran-ges it may be desirable scopic pair is»V visible when viewed' inl light. polar izedfi‘n aplane'at 90°' to said» ñrst named> plane; a. light. sourceA positioned on 'the side of- said' reticle most.; `distant'- from saidl viewingv means, light from said sour-ee being' transmitted throughÍ said reticle, collimator means- positi'oned between said reticle and said 'viewing means ata location out of saidÍ imageforming meansi for collimating. ‘light’4 passing through .the reticlel and to rely only upon the human interocular, and 10 directing a portion thereof to one of said viewing means and another portion to the other of said Fig. 4 illustrates diagrammatically a modification of the invention suitable for such use. One. eye of the observer is indicated at 40 as viewing the held through a single transparent mirror 42, and viewing means, and analyzing means in the field of each viewing means between said reticle- and said viewing means whereby only one indicia ele ment of each stereoscopic pair is observable through one viewing means and only the other reticle 45, lens 46 and a pair of analyzers 48, one indicia element of each stereoscopic pair is ob for each eye of the observer. Many other modi servable through the other viewing means. flcations will doubtless be apparent to those 3. In a range ñnder having a left-eye and a skilled in the art, and are to be construed as com_ 20 right-eye viewing means through which an ob ing within the scope of the invention. server looks when viewing an object to be ranged It is also to be understood that the following and means for increasing the interocular of the claims are intended to cover all the generic and observer, in combination, a reticle positioned in speciñc features of the invention herein described, the field of said viewing means, said reticle being and all statements of the scope of the invention which, as a matter of language, might be said 25 formed of transparent material having predeter mined areas therein which are rendered light po to fall therebetween. larizing and which form groups of indicia ele What is claimed is: ments, pairs of indicia elements in the different 1. In a range finder having a left-eye and a groups being spaced apart for stereoscopic com-v right-eye viewing means through which an ob server looks when viewing an object to be ranged 3f). bination when viewed stereoscopically, the spac ing between the stereoscopic pairs of indicia ele and means for increasing the interocular of the ments in the diiîerent groups being different'and observer, in combination, a reticle positioned in of magnitudes to cause the stereoscopically com the field of said viewing means, said reticle being bined indicia elements in each diiferent group to formed of transparent material having predeter-l ' mined areas therein which are rendered light 35 appear in said held at predetermined but differ ent apparent distances from lthe range iinder polarizing and which form at least two indicia when viewed stereoscopically through said view elements spaced with respect to each other. to pro ing means, said areas forming said indicia ele vide a stereoscopic pair which can be fused when the reticle system comprises light source 44, viewed stereoscopically, the spacing between said indicia elements forming a stereoscopic pair being of a magnitude to cause the fused indicia ele ments to appear in said ñeld at a predetermined apparent distance from the range finder when viewed through said viewing means, said areas being predeterminedly polarized so that only one 45 of said indicia elements of a stereoscopic pair is ments being predeterminedly polarized so that only one indicia element of each stereoscopic pair is visible when viewed in light polarized in a pre determined plane and only the other indicia ele ment of each stereoscopic pair is visible when viewed in light polarized in a plane at 90° to said first named plane, and analyzing means in the ñeld of each viewing means between said reticle and said viewing means whereby only one indicia element of each stereoscopic pair is observable through the left-eye viewing means and only the visible when viewed in light polarized in a prede termined plane and only the other of such stereo scopic pair of indicia elements is visible when viewed in light polarized in a plane at 90° to said 50 other indicia element of each stereoscopic pair is observable through the right-eye viewing means. first named plane, and analyzing means in the 4. A reticle for a binocular range ñnder, com ñeld of each viewing means between said reticle prising transparent material which is capable of and said viewing means whereby only a different being rendered light-polarizing when in `a molec indicia element of a stereoscopic pair is observ ularly oriented condition by Vthe incorporation able through each Viewing means. therein of a dichroic material, said reticle mate 2. In a range iinder having means for forming rial having the molecules thereof in at least one a left-eye image and a right-eye image of an ob predetermined area substantially oriented in a ject being ranged and also having individual left predetermined direction and the molecules there eye and right-eye viewing means which are opti of in at least a second predetermined area sub cally aligned respectively with said left-eye and stantially oriented in a direction substantially at right-eye image forming means and through 90° to said first named direction and also having a which an observer looks simultaneously with his dichroic material incorporated in each yof said left eye and his right eye for viewing said respec areas, each predetermined area forming at least tive images, in combination, a reticle positioned one of a stereoscopic pair of indicia elements, the in the field of said-viewing means, said reticle be , ing formed of transparent material having prede termined areas therein which are rendered light polarizing and which form at least two indicia elements spaced with respect to each other to pro vide a stereoscopic pair which can be fused when k viewed stereoscopically, said areas being prede terminedly polarized so that only one indicia ele corresponding elements of each pair being spaced apart by a predetermined distance for stereo scopic combination to appear in a plane located at a predetermined apparent distance from an observer when viewed stereoscopically by said observer. _ 5. A reticle for a binocular range finder, com prising transparent material having predeter- ' ment of a stereoscopic pair is visible when viewed in light polarized in a predetermined plane and mined light-polarizing areas provided vtherein only the other indicia elementV of such stereo which form a plurality of groups of indicia ele 2,404,302 , . 7 8 . ments, pairs `of indicia elements in’each group being vspaced apart for stereoscopic combination when viewed stereoscopically, the spacing between the indicia elements in different groups being Vdif transmissionaxis of a light-polarizing area form ing one of the indicia elements of each stereo scopi@V pair being substantially at 90° to the trans mission axis of a lightèpolarizing area forming ferent and of a magnitude such that stereoscopic pairs of indicia elements in the different groups appear in planes located at different and prede termined apparent distances from an observer the other element of each stereoscopic pair of Who isV viewing the reticle stereoscopically, vthe DEXTER P. COOPER, Jn. ï indicia elements, Y ' EDWIN H. LAND.