DE2829191A1 - DEVICE FOR IMAGE STABILIZATION FOR A STABILIZED OPTICAL DEVICE WITH AN IMAGE UPRATING PRISMA - Google Patents

Description

The invention relates to stabilized optical devices and, more particularly, to stabilized monocular optical devices with an image erecting prism that is on the optical axis of the lens and the ukular is arranged.

Stabilized optical systems have been used in monocular optical devices such as monocular telescopes, around optical systems with a larger magnification (e.g. a magnification of more than 7) to be able to use in conditions in which otherwise husky movements and movements of the vehicle the received images were so perturbed that they are meaningless will. Typical uses are on the lord of a ship, one

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BANK: DRESDNER BANK, HAMBURG, 4 030 44 «(BLZ 200 800 00) · POST CHECK: HAMBURG 147807-200 ■ TELEGRAM: SPECHTZIES

ORIGINAL INSPECTED

Reconnaissance aircraft, in land vehicles and the like. Even though As the description extends to "monoculars" it should be understood that such systems are not restricted to telescopes can also be used in cameras and binoculars such as binoculars.

Although some initial systems stabilized with respect to the objective lens system, it has been since It has long been noticed that a stabilized element between the objective and the eyepiece is effective, is the most satisfactory element for stabilizing.

An objective lens or an objective lens system leads to Generation of an image (reversal and reversal of the image) with the collimated light emanating from a distant object is recorded. To get the picture back in a suitable state

1 b , it is necessary to provide one or more elements which also lead to an inversion and reversal of the image. This could be achieved by a different lens system. There are also systems of mirrors and prisms that do this. Various solutions were used in earlier devices; Most satisfactory approaches use an optically aligned image erecting prism, such as one described in an article by Lavid B.! 'raser entitled "Design of a Low Cost, Hifh Magnification, Passively Stabilized Monocular , the

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Stedi-Eye (construction of a cheap, passively stabilized monocular with high magnification, the Stedi-Eye) " carries and in

August
SPIE Proceedings, Volume 39 »/ 1973. Such a prism is also described in U.S. Patent 4,013,339 entitled "Optical Image Stabilizing System" by Kunio Ando et al. Both of these documents form part of the disclosure of the present application.

Techniques for stabilizing optical devices have moved from the gyro-stabilized central afocal device Mark Systems Model 1610 to programmed stabilization converted using hydrostatic techniques, up to the use of springs and bearings to produce mostly tuned ones and damped isolators, to the axially oriented inertial stabilization systems shown in U.S. Patent 4,013,339 are.

Although the various techniques are successful to some extent, the most successful are large, cumbersome and expensive.

The object of the invention is therefore to create an improved stabilization mechanism for an image-erecting element, which is included in the aligned optical system, the

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stabilized marriage at a distance from the optical Imaging path is arranged, whereby its shortening is enabled, in the conventional gyroscopic parts which do not have through openings as in US Pat. No. 4,013,339.

The solution according to the invention consists in a device for image stabilization for a stabilized optical device with an image erecting prism, which is arranged in the housing of the device on the optical axis between the objective and the eyepiece is, in that a gimbal ring or frame is rotatably mounted in the housing so that its ITormal with respect to the optical Axis is pivotable that the image erecting prism is pivotable about an axis intersecting the optical axis so on the gimbal is attached that it is pivotable about an axis forming an angle with the pivot axis of the Ilardan ring, that a Gyroscope, the axis of which is parallel to the optical axis, is pivotally connected to the gimbal that a secondary connecting element pivotable with the gyroscope and the prism

whereby
is bound, / the points of connection with the points of connection on the gimbal form a parallelogram, and that the gimbal form an outer gimbal element and the gyroscope and the prism form inner gimbal elements for maintaining the stabilized axial alignment of the image-erecting prism.

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According to the invention, a combination of elements is used in order to achieve a shorter than previous systems to obtain an optical imaging system, the imaging system being a lens with a wide field of view, a Pechan roof prism, which is stabilized by a mechanism located at a distance from the optical axis is, and an eyepiece with a diverging lens, which is arranged in front of the actual image plane, in order to increase the focal length Shorten without shortening the interpupillary distance, and with a field lens to compensate for the field curvature having.

A preferred embodiment of the invention includes a system for stabilizing an image erecting prism, which is arranged axially between an objective and an eyepiece, the stabilizing mechanism itself, however, on an axis which is parallel to the optical axis. The prism is gimbaled to a yoke, which itself is gimbaled to a gyroscope. Las prism and the gyroscope are linked so that the prism is accurate the same movements in elevation or azimuth as the gyroscope performs.

The image erecting prism is preferably a Pechan roof prism, that in the converging light from the lens and

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acts in front of the image plane. The lens not only has a relatively long focal length (e.g. 10 times the focal length of the eyepiece), but also a wide field of view.

The entire optical imaging system is further shortened by the eyepiece, which has a diverging lens in front of the image plane has to send diverging light to the field lens of the eyepiece. In this way the eye candy can be kept long enough, however, a further shortening of the focal length of the eyepiece and a reduction in scope the curvature of field that occurs with large diameter lenses used in wide field optics will.

The invention is described below, for example, using an advantageous embodiment with reference to the accompanying drawings. Show it :

Fig. 1 is a cross-sectional side view of a preferred one Embodiment of the invention}

Fig. 2 is an oblique view to illustrate the inversion effect of a Pechan prism

Fig. 3 is an oblique view to show the reverse side

the effect of the rooftop on a Priemaj

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4 is an enlarged cross-sectional view of the gyroscope and related parts of the embodiment of Fig. 1j

Figure 5 is an end view in cross section of the embodiment shown in Figure 1; and

FIG. 6 shows a schematic view of the optical components of the eyepiece of the embodiment shown in FIG. 1.

In Fig. 1 is a cross-sectional side view of the invention stabilized monocular shown. The housing of the monocular has many precision parts that are typically manufactured by casting and machining techniques and assembled in accordance with well known methods. Even though Many parts are shown, not all parts are identified because the assembly procedure for those parts is well known.

Generally speaking, however, the housing 10 has an objective lens system 12 and an ocular lens system 14, both of which are centered on an optical axis 16. Each of these Lens system is attached so that it cannot move laterally away from the axial location, although, as is typical, the eyepiece lens system can be moved axially around the image

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to focus precisely. The lens 12 includes a glass front cover or filter 18 and three optical ones Lenses 20, 22 and 24. As shown, lenses 20 and 24 are positive lenses and lens 22 is a diffusing line. Together they can be used as a "triplet" with good imaging properties in the remote from the axis The range and the required focal length, although in any given system the focal length and the imaging properties can be larger or smaller or worse or better. The good imaging properties in the area distant from the axis are necessary so that the instrument has a viewing angle of 6.5 more apparent at all times Has movement due to the disturbance cone of ί 6.5 of the prism. The objective lens system must therefore be a whole Capture the field of view at an angle greater than 19.

The precision ocular lens system 14 includes six lenses a; the purpose of these lenses will be described in more detail below.

Between the objective lens system 12 and the ocular lens system 14 is an image-erecting element in FIG. 14 on the optical axis

26th
Shape of a Pechan roof prism / arranged. In order to better understand the effect of a Pechan roof prism, reference is now made to FIGS. 2 and 3.

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OOPY

halves having opposing diagonal surfaces making angles of 45 degrees with the input surface of the half-prism closest to the object and the output surface of the half-prism closest to the image. The air gap between these surfaces is typically 2 mm wide. In the non-roofed Pechan prism, the light is reflected 5 times before it emerges on the same axis on which ee entered the prism, namely from the diagonal surface of the first prism, the silvered outer surface of the first half-prism, the Output surface of the first into the second half prism, the output surface of the second half prism and upwards and from the upper inclined surface to the input surface ^ν "'θ.βΒ second half prism and finally from the output surface of the second half prism the incoming image is turned upside down. For reasons which will be described more clearly below, however, it is also necessary to carry out a page reversal of the image. It is well known that for this purpose a roof can be added to one of the half prisms, such as the one in Fig 3 to obtain a sixth reflective surface and Bowohl reversing as well as side reversing the Image to achieve. In this case, the top of the roof is arranged on the upper sloping surface of the outlet element or second half-prism. This reversing and page turning is possible

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COPY

known as image erection. Bas Pechan roof prism can expediently referred to as a "bildaufrichtend.es prism" which has a strong shortening effect due to its folded configuration.

In the present system, the prism is arranged in front of the image plane of the objective lens system and therefore works with converging light. It does not lead to any additional enlargement or reduction and has no effect on the effective focal length. Because of its index of refraction however, the prism has an elongating effect on the rear focal length of the objective lens system.

The description of the construction shown in Fig. 1 will now be continued. Bas prism 26 is to some extent fragile and therefore in a cast prism mount attached, which also allows the connection of the prism for inertial stabilization. First is an outer gimbal or frame 30 attached perpendicular to the housing 10 via bearings. These bearings enable the main cardan ring 30 to perform a pivoting movement about an axis in the azimuth direction. Bas prism 26 is with the outer cardan ring 30 on the optical axis at a point 34, which is in the middle between the nodal point of the objective lens system and the nodal point of the ocular lens system is arranged, such as

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this will be described more clearly below. This connection at point 34 enables the prism 26 to perform a rotary motion in relation to the elevation angle. The nominal mobility of the prism 26 is i 6.5 ° from the center away in both azimuth and elevation directions, although less or more freedom of movement can be provided if so desired.

The gyroscope 36 is attached to the outer gimbal ring 30 connected to a location which is a distance from the optical axis 16 and is parallel with that axis, wherein the junction point 38 is directly above the point 34 so that a line from point 38 to point 34 ^ ei of this embodiment would be perpendicular to the optical axis 16.

A secondary connector 40 connects the gyroscope or the hotorkardan element 36 with the casting that the Priema 26 encloses, via pivot points 42 and 44 that point 44 in relation to point 34 and. the Point 42 is axially aligned with respect to point 38. In fact, it is not necessary. It is necessary, however, that points 42 and 44 form a parallelogram with points 38 and 34 form. It can now be seen that as the gyroscope 36 rotates about point 38, the prism 26 rotates about one same amount will spin because of the connection that goes through

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the secondary connector 40 is created. Just like that the gyroscope 36 cannot rotate about point 32 without that the prism 26 rotates by the same amount.

4 is a cross-sectional view of the gyroscope 36 shown in more detail. The portion of the gyroscope that is connected to the outer gimbal 30 is the motor gimbal 36, which is connected to the motor gimbal housing 48 with bolts and is separated from the axis of rotation 52 by bearings 51, which is connected to the armature 54. The commutator of the motor is indicated by the reference numeral 56 and the brush assembly the reference numeral 58 denotes. The wheel-shaped rotating The main mass 60 of the gyroscope is essentially a large flywheel connected to the axis of rotation.

With this wheel-shaped rotating main mass 60 is connected a precession disk 62 made of aluminum, which is spherical and has a large central opening; Has. A magnet 4, which can be either a permanent magnet or an electromagnet, has a core 66 , the entire structure having slots into which the disc 62 penetrates when the gyroscope 36 is pivoted.

It is well known that when a gyroscope moves off axis should be, it strives to create a reaction movement in the

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Execute an angle of 90 to the applied force. To counteract this reaction, it is necessary to provide a specially designed precession element. The precession element is designed so that when the disk 62 cuts into the magnetic field of the magnet 64, a force is generated which is proportional to the eddy currents that are formed in the precession disk.

Due to the laws of precession, the gyroscope requires damping in order to dissipate hutation energy.

Previously known systems in which a loss coupling with damping are provided between gyroscopic components and a stabilized element, reduce such nutation disturbances very strong, but have the disadvantage of causing delayed caching or misalignment of the established Cause element. During scanning observations or the like, the element therefore easily floats or moves away from the axis. This is the case with the present Construction avoided by the rigid coupling of the gyroscopic components and the stabilized element is effected by the connecting element 40. Nutation dampening is achieved by the damping flywheel 68, which is with the outer gimbal ring 30 is connected. The main mass of the flywheel is connected by bolts to a ring of energy-absorbing vinyl polymer with a large damping coefficient,

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the connection by means of bolts 70 at a number is made of bodies that are arranged in a spoke shape are. The ring is connected to a surface of the gimbal ring 30 via a washer 72 and bolts 74. Camp 76 allow the mass of the flywheel to move freely to and fro without changing the center of gravity.

The locking mechanism can also best be explained in connection with FIG. A bolt or pin 78 that pushed outwardly from frame 80 along the axis of gyroscope 36 is, cooperates with the inner tapered surface 82 of a piston 84 which fits over the pin. The cone-shaped Area reduces in its center to a hole that mates with the bolt. A rocker arm 86 operates the piston, the position shown being the locked position. It should be noted that when locked, the gyroscope is held mechanically so that its axis is parallel to the optical axis. The spring 88 exerts a slight inward movement directed gate tension on the piston 84. The entire locking mechanism is fastened to the housing 10 with bolts 90.

The locking mechanism can be actuated by pressing a push button 91 unlock the gyroscope.

Balance weights 92 are provided and about a nut mounted on a threaded bolt 96. Electric Leads 98 provide electrical connection from the printed circuit

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Circuit card 100 for the power supply to the gimbal element of the rotary motor j The battery connection is established by wires 9Ö

en

posed. The wires or connection / 98 go through point contacts 104 at a number of locations therethrough, although other means of supplying electrical power may be provided to get to the motor of the gyroscope. The on-off push button is denoted by the reference numeral 1O6.

In a typical embodiment, full operating speed will be approximately 25 nautical miles. reached after switching on. The starting torque is approximately 0.0092 Fm (1.5 in.oz.). The unit requires 1.6 watts of power on a 10-ToIt input and requires three 4.5 volt batteries.

In this version, the entire arrangement is through various smocks gufa sealed that are shown but not fully described. However, the arrangement is once sealed, it is pressurized through a drain valve 100.

The eyepiece lens assembly 14 is housed in its own housing 110 which has a pin 112 movable within a slot in the casting 115 actuated by the focus 114 for the eyepiece. The ocular lens system is protected by an eye shield 118 to which the eye of the

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BAD GRIGJNAL

User is created . By, the Aug-enab shield 118 is a complete cover against the forehead of the user to provide protection against reflection and glare due to the fact that it surrounds the eye, and around the
To create means by / the entire arrangement can be brought into a fixed position relative to the user. In Fig. 5, the shape of the outer gimbal 30 and secondary connector 40 is shown more fully. To prevent the prism from moving relative to the gyroscope, the bearings are preloaded or preloaded at the pivot points about points 42 and 44.

Also in Fig. 5 is the optimal electrical feed-through connection shown at contact IO4.

The ocular lens arrangement according to the invention is schematically shown in FIG. 6 shown. In precision eyepieces, six or more lenses are commonly used. Hit the in conjunction with the However, some particular advantages are achieved in the stabilized optical system just described Arrangements according to the prior art are not available. These advantages are achieved through the arrangement of the diverging lens 126 and the field lens 128 received.

The dashed location I30 is the location for the image plane that results from the objective lens system and which is still slightly displaced by the refractive properties of the prism.

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It can be seen that placing the field lens in the conventional location without the benefit of lens 126 would not have the desired effect of flattening the field curvature of the system, which is required because of the wide field of view properties of the lens quite large field lens. In addition, in order to obtain a magnification of the order of 1.6 times the magnification of the ocular lens system, a rather strong diverging lens is required. By arranging the diverging lens directly in front of the original image plane (in the direction of the objective lens system), both requirements are met. In addition, the effective focus is not so shortened that an unreasonably short eye relief is obtained
even if further magnification is effected by the additional lenses of the system.

To improve the relationship of the lenses in the ocular lens system

to understand the lens system is designed so that the distance between the user's eye and the final surface of the lens of the eyepiece, measured along the optical axis, is greater than the focal length of the eyepiece B. As a result of this relationship, a such eyepiece can also be used by people who wear glasses, to use a large eye shield and the like without it being necessary to narrow the field of view under these conditions.

Bas wide-angle ocular lens system essentially has four components that are axially aligned with each other and

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that have gaps between them, the first component has a diffusing effect and is placed in front of the real image projected through a lens inserted into In connection with the eyepiece. So a real picture is only formed after the light rays have passed through the diverging lens have passed through. The second component is the real image at the location or in the neighborhood of the same arranged and has a collecting effect for the light, the third and fourth components also have Collecting effect on the light.

The various components of the ocular lens system are structured as follows:

The first component consists of two lenses, one of which, preferably the first lens, which eats the lens next , has a collecting whirlcun ^ for light. The first lens can also comprise a meniscus converging lens, the concave surface of which is directed towards the objective. The second lens of the first component is a double concave lens. The first and second lenses of this first component can be glued together.

The second component consists of a single light-gathering lens, the surface of which is directed towards the eye has a smaller radius of curvature than the surface facing the lens.

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The third component consists of two lenses glued together, whereby the lens directed towards the objective has a diffusing effect Has. ! This lens is constructed as a lieniscus lens, the concave surface of which is directed towards the eye. The second Third component lens is a double convex lens.

The fourth component consists of a single light-collecting Meniscus lens, the concave surface towards the eye is directed.

Typically, with V / ei two-angle eyepieces bein JilrfLe-Jyp, an eye relief is achieved which is only ΰ.7 times the effective focal length of the eyepiece. I-iib the execution .; sforrn, which was described in connection with: FIG. G , however. an eye relief of 1o sin with an effective !:. : reuawei ie from I6j5 EM · achieved. This makes a wide-angle miniature. The distance between the eyes is reached, which is an iakfeor 1.09 firöi'er than the effective focal length.

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ORIGINAL INSPECTED

Claims (1)

Claims 1. _{Device for Bildstabilisierun ft} for a stabilized optical device with a biidaufrichtendeu prism, which is arranged in the housing of the device on the optical axis between the lens and eyepiece, characterized in that wet in the housing (lü) a gimbal ring or frame (JO) rotatable is attached in such a way that its normal is pivotable in üezug * on the optical axis (16) that the image erecting prism (26) is attached to the gimbal ring (30) so that it can pivot about an axis (34) intersecting the optical axis (16), that it is pivotable about an axis forming an angle with the pivot axis (32) of the gimbal ring (30), that a gyroscope (36), the axis of which is parallel to the optical axis (16), is pivotably connected to the gimbal ring (30) is that a secondary connection element (40) is pivotable with the gyroscope (36) and deiii whereby
Prism (26) is connected, / the connection points (42, 44) with the connection points (34 »38) on the cardan ring (30) form a parallelogram, and that the cardan ring (30) is an outer cardan element and 809883 / 0.9., 3S BANK: iDHESDNER BAWK, HAMBUBG, 4030448 (BLZSOOiOOOO) POST CHECK: HAMBURG 147607 ^ 200 TELEGRAM: SPECHTZ1E3 ORIGINAL INSPECTED the ijyrsoskop (36) and the prisoia (2c) inner i.'ardarielemente amn maintaining the stabilized axial alignment of the üildnufrichtenden i'-rismge (26). 2. liünrlci; turif, according to claim 1, characterized in that £ · e k e ti η!? draws that the cardan bearing; of the "iTLsmati (2ö) at a place (34) which eats in the middle between the junction of the lens (12) and the junction of the Gkulars (I4) is arranged. _>. Device according to claim 1 or 2, characterized e g denotes that the Erect image Frisma (26) is a Lechan-roof prism (Techan roof prism). 4. Kinrichtunf. according to any one of claims 1 to J, characterized f. · e k e η η a e i c h η e t that a precession element is provided iat that an aluminum caeibe (b2) me. a * taittip / en ^ 5 üffnunf; which is attached to the rotating main mass (tO) of the gyroscope, and has a magnet (o4), which rests on the housing Mj) and so for receiving the edges of the disk (62) who'xi that Gyroscope (36) is rotated away from its axis, is provided with a slot that eddy currents through the Lelativbevra ^ un ^ ·. between the disk (62) and the Ua ^ net (64) creates weave through which a force is exerted to center the OyrcE-icops (26). 8XJ98S3 / 09 3 8 OInspected copy 282019.1 f'hivm .. ', IWj ( ¹ Ii t.iiipct, iit ι / us [ι, ic >, <■ 1 Ms ι \ , ο ».im ■ ί (r> l · f η ii ζ ρ i C Ii υ et, Λ.ν- · <■. ( Οι "i- ¹ 'f'cl e ι' ■ 't ■: <· ίι, ·: ϊ · - rjiirj chtun en before / -. Erpt" ii bIiH , dif e? i τ ■ r-. ι.-ο '] r.pn (7ij "ΐ ·' ^ ji. f jriiu j .'IfU-. es ι den kef ei ί t'riu en κ · ίΊ ( ^ c) niifv; i nrn, · ^; ο · τ uj'h ¹ J ι i '(ii. with ti j-es Lc- 1' rum recording dec Lolzi-ns Γί ^! / v ^ 'joijt, wofi cntvjeder der "olzen (7 ^ / or the ^ ef.oli ^ .vmi, · c ifil (· .;; j π jic-hscr ^ 'iclitiinp: in it dein iiyroHl'op (J ¹ ') vc-rbuji ^ p "j £ i: πτ ·> _π _ l« i the other Veil in / icliflenrd chturv nc vprrcliiebbHr Jt-t, (ϊ.τ! '. the gyroscope (3l-) aiechaniHcJi aireiiisrbar iai. 1i t>. Establishment naoli claim ^l j , dadurcli fe. <E ι η - draws that the movable part (7 ^ i ¹ ^ - 'in iiici-turif zum (iyoskop iederbelaatet ir? t, veun the part ^ 7 ^, ¹ J «'' j si · firiner arrestierenden iDtellunf; int. 7 »Finrichtuur according to one of the'claims 1 bia (> , through this 1 '"/ t i'. c- η η 2 eic Ii η et that a JjMiupiunirBKcJiviuiii'rad ((J ^- O v.irfeseliCK is that with the lLardaniinf, (; Ii. Device according to claim 7, characterized by the fact that the damper has an unrnschwun, wheel an enrr ^ ieab- Ί'μ Morbierendets vinyl polymer with a high umpfun; akoei f i '/ inside, over which the Iiauptinasse (6ü ) of the Lichwurifjradeö and the I iirdanririf (3Ci) are connected. 8 0 ° ι ° ^p Π / 0 9 3 8 COPY ΐ BAD ORIGINAL 9. Stabilized optical device with a bildaufriehtenden prism, aas in the housing of the device on the optical axis between the lens ^ναϊ ^ eyepiece is arranged, characterized in that the lens (12) and the eyepiece (Η) firmly connected to the housing (1O) are that the input and output surfaces of the prism (26) are perpendicular to the optical axis (16), that the prism (26) is freely movable in relation to the angle of elevation when the housing (10) is moved, and that a gyroscope (36 ) is provided, which is arranged outside the optical axis (16) and connected to the prism (26) so that it can be rotated through a common angle with the same to achieve an inertial stabilization of the elevation angle. 10. Apparatus according to claim 9 1, characterized in that that a gimbal connection (32) between the housing (1O) and both the prism (26) and the gyroscope (36) to achieve a common rotary movement about an axis which is perpendicular to the optical axis (16) to achieve an inertial azimuth stabilization is provided. 11. Apparatus according to Anepruch 9 or 10, characterized in that the image erecting prism (26) is a Pechan roof prism is. 809883/0938 12. Device according to one of claims 9 to 11 »characterized in that the objective (12) in connection with the eyepiece (14) achieves an approximately 10-fold magnification with a respective field angle of approximately 6.5 ° . 13 · Device according to one of claims 9 to 12, 'thereby characterized in that through the image erecting prism (26) a movement of + 6.5 with respect to both the elevation angle as well as in relation to the azimuth executable is. 14. Device according to one of claims 9 to 13, characterized characterized in that the lens (12) has three Lenses (20, 22, 24) for eliminating the field curvature Having angles of more than 9 from the axis to achieve a total field of view of 19.5 °. 15 · Device according to one of claims 9 to 11, characterized characterized in that the gyroscope axis is parallel to the optical axis (16) and that the objective (12) is three Lenses (20, 22, 24) for eliminating the field curvature at angles of more than 9 deviations from the axis and that at the same time an eyepiece (14) is provided with six elements is, so that a magnification of about 10 times with an image field of 6.5 ° is achievable. . 5 _ BAD ORiGSNAL 809883/0938 16. Device according to one of claims 9 to 15 , characterized
characterized in that through the eyepiece (I4) a
The ratio of the eye distance to the focal length of about 1.09 is achieved so that an optical vertex distance of about 24 cm (9 »5 inches) from the anterior vertex to the pupil plane at the exit is achieved. 8 0 9883/0938