Spotting System for Binoculars and Telescopes

Europaisches Patentamt 0 348 566 J> European Patent Office Publication number: A1 Office europeen des brevets

0 Application number: 88305922.2 @) mt. ci.4 G02B 23/00

@ Date of filing: 28.06.88

@ Date of publication of application: 0 Applicant: Schneider, Richard T. 03.01.90 Bulletin 90/01 17 Alachua Highlands Alachua Florida 32615(US) @ Designated Contracting States: CH DE FR GB IT LI Applicant: Keates, Richard H. 456 West 10th Avenue Columbus Ohio 43210(US)

0 Inventor: Schneider, Richard T. 17 Alachua Highlands Alachua Florida 32615(US) Inventor: Keates, Richard H. 456 West 10th Avenue Columbus Ohio 43210(US)

0 Representative: Geldard, David Guthrie et al URQUHART-DYKES AND LORD Tower House Merrion Way Leeds West Yorkshire LS2 8PA(GB)

Spotting system for binoculars and telescopes.

@ An auxiliary spotting optical system for binocu- binocular until the target is within the field of view lars and telescopes includes an auxiliary objective indicator. Shifting the mirror to its second position lens proximate the principal objective lens, a princi- breaks the light path through the spotting system pal magnification system field of view indicator and and opens the principal magnification optical path, an image transfer arrangement between the field of and the target appears magnified to the power of-the view indicator and the ocular lens of the binocular to principal magnification system. ^ bridge the optical gap created between the image plane of the auxiliary objective lens and the focal Tl plane of the ocular lens to create an optical system ^delivering a 1x magnification to an observer with CD normal eyesight. A movable mirror in the optical and the ^Opath of the principal magnification system — \t. spotting system determines which optical system is 00 active. In its first position the mirror directs light 2 passing through the auxiliary objective lens, the field of view indicator, the image transfer arrangement to ©the ocular lens, and blocks the principal magnifica- g^tion optical path. The viewer is afforded a wide field HI of view without significant magnification with an indication of the area encompassed in the principal field of view. The user can move the magnification TV

Xerox Copy Centre EP 0 348 566 A1

SPOTTING SYSTEM FOR BINOCULARS AND TELESCOPES

BACKGROUND OF THE INVENTION a principal objective lens and an ocular lens defining a principal magnification optical path; (b) an auxiliary objective lens; (c) light diverting means This invention relates to telescopes and bin- comprising a mirror movable between a first and a oculars, and more particularly pertains to a novel 5 second position; and (d) actuation means adapted spotting system for such instruments which facili- to displace said mirror from said first position to tates locating the target and which permits instanta- said second position and from said second position neous shift to magnification of the target after it is to said first position; said movable mirror in said located. first position reflecting light passing through said Binoculars are usually provided with magnify- w auxiliary objective lens onto the focal plane of said ing capacities or power ranges of from 6x to 10x ocular lens to permit a substantially unmagnified and at the latter magnifying power the field of view view through said ocular lens and blocking said is fairly limited. Consequently, if one wants to lo- principal magnification optical path, and in said cate a target, e.g., an airplane in the sky or a buoy second position breaking said optical path through at sea, it usually means sighting through the bin- 75 said auxiliary objective lens and opening said prin- ocular and scanning the field of vision more or less cipal magnification optical path to permit the mag- randomly until the target is picked up. In some nified target image to be viewed through said ocu- cases the approximate general location of the tar- lar lens. get can be ascertained with the naked eye; how- The user first sights through the telescope or ever, one is still faced with then having to locate 20 binocular with the movable mirror in its first posi- the target through the binocular at the magnifying tion and the active light path through the spotting power. Since the field of view is limited, this can be system which comprises the auxiliary objective a difficult task especially in those instances where lens, and is thus afforded a wide field of view with the target is small or is moving. substantially no magnification. The user can then A zoom lens arrangement could be employed, 25 shift the mirror into its second position thereby the lower power being used first to sight the target breaking the light path through the spotting system and the magnifying power thereafter increased as and the active light path is through the principal desired. To achieve the desired magnification takes magnification system. time as the relative positions of the optical ele- Preferably the principal magnification optical ments in the zoom lens arrangement are changed 30 path has a fixed magnification of from 6x to 10x. to effect magnification. During this time the target The auxiliary lens desirably lies proximate to, and may have moved out of the field of view, neces- substantially coplanar with, the principal objective sitating relocation of the target. In addition zoom lens. lenses, because of their relatively sophisticated and Preferably a principal magnification optical path complex construction are expensive to manufac- 35 field of view indicator means is situated between ture, cannot stand up to rough handling and are said auxiliary objective lens and said ocular lens, susceptible to failure in severe or adverse use said field of view indicator means defining the area conditions. Further, such lenses are bulky and in- to be viewed through said principal magnification crease the weight as well as the cost of the binocu- optical path when said optical path through said lar. 40 objective lens and said field of view indicator Accordingly, it is desirable to provide a spot- means is broken. The user can thus move the ting system for binoculars and telescopes which binocular until the desired target is within the field facilitates target location and which will permit in- indicator, and on changing the position of the mov- stantaneous switching to the magnifying power able mirror the area in the field indicator will then once the target is spotted. 45 appear in the user's view magnified to the power of the principal magnification system.

OBJECTS AND SUMMARY OF THE INVENTION DESCRIPTION OF THE DRAWINGS 50 The invention seeks to provide a novel spotting system for binoculars and telescopes which facili- In the accompanying drawings, in which sev- tates target location and magnification of the target. eral embodiments of the invention are illustrated, According to the invention a telescope or bin- Fig. 1 is a partial sectional view of a conven- ocular comprises a barrel and, within the barrel, (a) tional prism binocular in which the present inven- EP 0 348 566 A1 tion is applied; the spotting system, comprising lens 30, the trans- Fig. 2 is an enlarged schematic of the optics fer lenses and the ocular lens 20. The focal length systems ofthe binocular of Fig. 1; and of the auxiliary lens 30 is equal to the focal length Fig. 3 is a schematic of an image transfer of lens 20. The lenses 32 and 34 are arranged so arrangement in accordance with an alternative em- 5 that the optical system composed of lenses 30, 32, bodiment of the present invention. 34 and 20 produces a 1x magnification to an ob- Corresponding reference characters indicate server with normal eyesight. A slight deviation from corresponding parts throughout the several views these criteria caused by the fact that the image of of the drawings. the auxiliary objective lens 30 might be at differing w locations depending on the distance to the viewed target will have the effect that said target viewed DETAILED DESCRIPTION OF THE INVENTION through the spotting system will be slightly magnified; however this will not detract from the present invention. A binocular incorporating the subject invention 15 Due to space limitations which will affect the is identified generally by the reference numeral 10 arrangement of parts within the binocular barrel 12, transfer lens. in Fig. 1 . As will become apparent as the descrip- it may be impractical to use a single tion proceeds, the spotting system of the present With continued reference to Fig. 2, a transfer lens invention is adapted for use in a conventional prism arrangement is shown as comprising a first transfer binocular. For the sake of brevity only those ele- 20 lens 32 and a second transfer lens 34 with a mirror ments of the binocular which are necessary for a 36 positioned therebetween to reflect the light at a full and clear understanding of the invention will be forty-five degree angle to assist in routing the light mentioned. In addition, it will be appreciated by path of the spotting system to the ocular lens. The those skilled in the art that the subject invention is transfer lenses 32 and 34 will also invert the image adapted for use in a conventional telescope and 25 and this can be rectified by a prism arrangement the terms binocular and telescope are used inter- 38 which functions in a manner similar to the prism changeably herein. arrangement in the principal magnification system. The prism binocular 10 includes two barrels 12 It should also be understood that the image trans- each- of which house the principal magnification fer arrangement could consist of a fiberoptics im- optics of the binocular principal magnifying optics 30 age conduit 39 (coherent fiberoptics bundle) in lieu system. The details of the construction of the spot; of the transfer lenses 32 and 34, and mirror 36 as ting system and the system's interaction with the shown in Fig. 3. principal magnification system of the binoculars A transparent plate 40 is positioned on the can be understood best with reference to Fig. 2, focal plane of the auxiliary objective lens 30. The wherein the principal magnification optical system 35 plate 40 bears indicia 42 to indicate to one sighting is identified generally by reference numeral 26 and through the spotting system the field of view at that includes the principal objective lens 14, prism sets instant of the principal magnifying system. The 16 and 18, and ocular lens 20 which function in the indicia may be simply a circle inscribed on the manner described above. plate, a color tinted disk or other conventional The auxiliary spotting system 28 includes an 40 means. auxiliary objective lens 30 of the same focal length A means is provided to allow the user to switch as the ocular lens 20 mounted at the front of the from the spotting system to the principal magnifica- binocular preferably in the same plane as and tion system almost instantaneously. The principal proximate the principal objective Lens 1 4. The aux- magnification system and the spotting system are iliary objective lens 30 has a relatively small diam- 45 configured so that a movable mirror 44 can be eter as compared to the principal objective lens 14 positioned in the light path of the principal mag- and will be equal to or only slightly greater than the nification system between the prisms 18 and the diameter of the ocular lens 20. The image created ocular lens 20 and in the light path of the spotting by the auxiliary objective lens 30 will appear be- system between the prisms 38 and the ocular lens tween one and two focal lengths (depending upon so 20. the distance to the target) behind said lens. Since An actuation mechanism 46 similar to one used the ocular lens 20 is in a relatively fixed position in singlelens reflex cameras is adapted to move the with respect to the lens 30 a gap exists between mirror 44 between first and second positions. With the image plane of the lens 30 and the focal plane mirror 44 in its first position (48 in Fig. 2) it ob- of the ocular lens 20. An image transfer arrange- 55 structs or blocks the light path through the principal ment is therefore utilized to bridge this optical gap, magnifying system. The operating or active light and may include one or more lenses of a suitable path is through the spotting system, i.e., through focal length so as to produce a 1x magnification of the auxiliary objective lens 30, plate 40, transfer EP 0 348 566 A1

lens 32, mirror 36, transfer lens 34, prisms 38, and said ocular lens and blocking said principal mag- off mirror 44 to the ocular lens 20. In this configura- nification optical path, and in said second position tion the user sighting through the binocular is af- breaking said optical path through said auxiliary forded a wide field of view without much magnifica- objective lens and opening said principal mag- tion. The field of view will include the principal field s nification optical path to permit the magnified target ofc view indicator to facilitate the location of the image to be viewed through said ocular lens. target. When the actuation mechanism is engaged, 2. A hand-held telescope or binocular as for example by pressing button 50, the mirror 44 claimed in claim 1 wherein the principal magnifica- moves into its second position (52 in Fig. 2) will tion optical path has a fixed magnification of from break the optical path through the spotting system, w 6x to 10x. and open the principal magnification optical path so 3. A hand-held telescope or binocular as it becomes the operating or active light path. The claimed in claim 1 or claim 2 wherein the auxiliary area seen in the field of view indicator in the lens lies proximate to, and substantially coplanar spotting system will now appear in view magnified with, the principal objective lens. to the power of the principal magnification system. 75 4. A telescope or binocular as claimed in any As noted above the actuation mechanism may one of the preceding claims further comprising a be of conventional construction well known to those principal magnification optical path field of view skilled in the art. It may be such button actuated as indicator means situated between said auxiliary ob- shown in which case the movable mirror 44 is jective lens and said ocular lens, said field of view normally in its first position and will move to its 20 indicator means defining the area to be viewed second position when the actuation button is through said principal magnification optical path pressed and remain there as long as the button when said optical path through said objective lens remains depressed. Alternatively, the movable mir- and said field of view indicator means is broken. ror may normally rest in its second position, mov- 5. A telescope or binocular as claimed in claim ing into the first position when the actuation button 25 4 wherein said field of view indicator means com- is depressed. prises a transparent plate within the focal plane of The spotting system discussed above need be said auxiliary objective lens and means on said provided in only one barrel of the binocular to the plate for identifying the area encompassed by said effective. Optionally, spotting systems can be pro- principal magnification optical path. vided in both barrels. 30 6. A telescope or binocular as claimed in claim Some advantages of the present invention evi- 5 wherein said identifying means is a circle in- dent from the foregoing description include a spot- scribed on said plate. ting system for binoculars which facilitates target 7. A telescope or binocular as claimed in claim location and which will permit instantaneous mag- 5 wherein said identifying means is a transparent nification of the target once located. 35 colored disk. As various changes can be made in the above 8. A telescope or binocular as claimed in any construction without departing from the scope of one of the preceding claims further including a the invention, it is intended that all matter con- transfer lens arrangement positioned intermediate tained in the above description or shown in the said auxiliary objective lens and said ocular lens accompanying drawings shall be interpreted as il- 40 and bridging the gap between the image plane of lustrative and not in a limiting sense. said auxiliary objective lens and the focal plane of said ocular lens to create an optical system delivering a 1x magnification to an observer with Claims normal eyesight. 45 9. A telescope or binocular as claimed in any 1. A hand-held telescope or binocular compris- one of claims 1 to 7 further including an image ing a barrel and, within the barrel, (a) a principal transfer arrangement comprising a fiber optics im- objective lens and an ocular lens defining a princi- age conduit positioned intermediate said auxiliary pal magnification optical path; (b) an auxiliary ob- objective lens and said ocular lens and bridging the jective lens; (c) light diverting means comprising a so gap between the image plane of said auxiliary mirror movable between a first and a second posi- objective lens and the focal plane of said ocular tion; and (d) actuation means adapted to displace lens to provide a 1x magnification to an observer said mirror from said first position to said second with normal eyesight. position and from said second position to said first 10. A telescope or binocular as claimed in any position; said movable mirror in said first position 55 one of the preceding claims further including reflecting light passing through said auxiliary objec- prisms in the optical path between said auxiliary tive lens onto the focal plane of said ocular lens to objective lens and said ocular lens and adapted to permit a substantially unmagnified view through correct inversion of the image. 00 00 EP 0 348 566 A1 0 o no OO * O 90 1<)

\A EP 0 348 566 A1

&o h-^

\h R-an

T— Zb Zb 42

/ PlancOfImagc\ 40 Acouiceo By \ /

Oejecnve LeisS A/\ -XIP7 I6

icq.2. European Patent Application Number J EUROPEAN SEARCH REPORT Office EP 88 30 5922

DOCUMENTS CONSIDERED TO BE RELEVANT with where Relevant CLASSIFICATION OF THE Categoryi~ ♦ „ .„ Citation of document indication, appropriate, of relevant passages to claim APPLICATION (Int. Cl. 4) A US-A-4 669 833 (M. MISE) 1-5,8 b Ud B ^/uu, n * Figures; column 1, lines 54-68; column 2, lines 1-6,23-28,53-60; column 4, lines 14-23,56-58 *

A PATENT ABSTRACTS OF JAPAN, vol. 8, no. 1,2 179 (P-295)[1616], 17th August 1984; & JP-A-59 72 416 (MINOLTA CAMERA K.K.) 24-04-1984 * Abstract *

A FR-A-1 474 156 (F. ARENE et al . ) 1 * Page 2, column 1, line 23 - column 2, line 40; figure 1 *

A US-A-4 548 481 (K. YAMADA) 1 * Column 6, lines 33-68; column 7, lines 1-52 *

A DE-A-3 318 Oil (C. ZEISS) 1 * * . Claims; figures technical fields • SEARCHED (IM. ci.4) A US-A-4 293 187 (I. ISHIBAI) 1 8 02 B 23/00 •Abstract; figures*

A FR-A-2 304 094 (SOCIETE D'OPTIQUE, 1 G 02 B 7/00 PRECISION ELECTRONIQUE & MECANIQUE - SOPELEM) * Whole document *

A PATENT ABSTRACTS OF JAPAN, vol. 6, no. 1 248 (P-160)[1126], 7th December 1982; & JP-A-57 144 519 (CANON K.K.) 07-09-1982 * Abstract *

The present search report has been drawn up for all claims Place of search Date of completion of the search Examiner I THE HAGUE 28-02-1989 WESBY P.B.

3 CATEGORY OF CITED DOCUMENTS T : theory or principle underlying the invention 3 E : earlier patent document, but published on, or a X : particularly relevant if taken alone after the filing date a Y : particularly relevant if combined with another D : document cited in the application g document of the same category L : document cited for other reasons 5 A : technological background t O : non-written disclosure & : member of the same patent family, corresponding p P : intermediate document document