DE2624446A1 - OPTICAL SYSTEM - Google Patents

Description

262U46

r / rn
J3IPL.-I.VG. B, RCIIOMERUS

NG. H. ARENJDl ¹ Hannover, the 2 *. Mei ISE

3 HANNOVKB

'Ci NtOSTK. 21. TKf ₁ EFOJf 32 4911

Re: P 726 / em - Applicant: Pilkington P.E. Limited

Prescot Road Sto Helens Lancashire (England)

¹¹ optical system "

The invention relates to an optical system, and more particularly to an optical system for binoculars See.

In previously known systems for binocular vision, in which an observer with both eyes is magnified Sees an image of an object, the magnification is generally that the focal length necessary to achieve a high magnification is limited to a numerical one Leads lens aperture that is larger than the maximum achievable in the open air, i.e. 1.0, if the device should be of an acceptable size

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The invention is based on the object of providing an optical system for binocular vision in this way improve that with relatively small dimensions a particularly high magnification is made possible

According to the invention, the optical system for binocular vision consists of a magnifying one Collective lens with an optical axis and means for receiving light from the lens, with a pair of partially transparent / partially reflective contact surfaces between fixed parts are provided, the contact surfaces on opposite sides of the optical Axis are arranged and inclined to this. These means also contain a pair of reflective ones Faces located on opposite sides of the optical axis, each of which reflective surface is further away from the optical axis than the partially transparent / partially reflective contact surface this side, and parallel to a partially transparent / partially reflective interface is arranged so that it emits light rays

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to an observer who reflected them over the partially transmissive / partially reflective interface from the lens parallel to light rays that have been received by the lens and through the partially transmissive / partially reflective touch surface get to the observer · A binocular observer can therefore with each eye the enlarged infinite See image that is emitted from the lens by light coming directly from the corresponding part permeable / partially reflective contact surface and / or from the corresponding reflective Surface has been received o Preferably each reflective surface is parallel to the partial transparent / partially reflective contact surface arranged on the same side of the optical axis, and the partially permeable / partially reflective contact surfaces are inclined to the optical axis so that they are in the direction of the Converge lens

The lens can have a relatively short focal length, for example on the order of 25mm.

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The reflective surfaces are preferred totally reflective and can be provided with a totally reflective coating. The partially translucent / partially reflective Contact surfaces can have a coating of suitable transmissive / reflective Have properties.

These reflective surfaces and contact surfaces are expedient with a prism system provided, and the aforementioned means can in particular at least one pair of rhombic Contain prisms whose opposing surfaces are these surfaces and contact surfaces form. The term "rhombic" is to be understood (as in the common sense) as not limited to a hexahedral solid figure, (but not excluding this) their Areas parallelograms with sides of equal length are o The expression also includes a parallelepiped, for example one whose opposite edges are inclined at an acute angle and which has faces, the parallelograms are and their abutting sides are of different lengthso

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A pair of rhombic prisms can be interposed on opposite sides of the optical axis a three-sided prism be arranged, the contact surfaces between the Triangular prism and the inner surfaces of the rhombic prisms adjacent to the axis are partially transparent / partially are reflective and the outer surfaces furthest from the axis of the rhombic prisms are preferably totally reflective.

It can alternatively be arranged two pairs of rhombic prisms that two prisms one side and two on the other side of the optical axis, the two prisms cemented to each other on each side of the optical axis and the contact surfaces cemented to one another are partially transparent / partially reflective, and the outer surfaces of the outer prisms, d.ho the surfaces furthest away from the optical axis, preferably totally reflective are. The inner surfaces of the inner prisms, i.e. those closest to the optical axis. Surfaces can be totally reflective, or it can be between

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a three-sided prism attached to them, with the contact surfaces between the three-sided Prism and the inner prisms are partially transparent / partially reflective.

When a three-sided prism is sandwiched between rhombic prisms, one is preferred Cover plate attached along the optical axis passing through the center of the three-sided prism.

Preference is given to abutting prisms on opposite sides of the optical axis acute-angled vertices touching the optical axis, however, in practice the vertices can be beveled, and the prisms provided with the bevels can touch the optical axis. The surfaces of adjacent prisms which lie opposite the lens are preferably located in the same plane, so that the acute-angled vertices (or bevels) which the optical Touch the axis, lie next to each other.

Plane-concave lenses can be combined with the exit surfaces of the rhombic prisms, e.g. with

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these must be cemented. The unused faces of the rhombic prisms are preferred matted or blackened.

The system can contain means to deflect the light path and in particular a light deflecting one Prism in the light path between the lens components of the collective magnification lens to be attached to one or more deflections of the light path through the lens cause.

The optical system according to the invention will be explained on the basis of exemplary embodiments which are shown in the drawing o They show:

1 shows the schematic representation

a first embodiment,

2 shows the schematic representation

a second embodiment,

Figure 3 is a schematic representation _o

a third embodiment,

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Pig. 4a, 4b and 4c modifications of the embodiments of FIG. 1, 2 and 3,

5 shows a further embodiment,

and

Figo 6, 7 and 8 arrangements for deflecting the

Light path so

The embodiment according to Pig. I consists of a magnifying converging lens 1 with an optical one Axis 0 · A prism system 2 is arranged in front of the lens, which consists of a pair of rhombic prisms and 4, which are arranged on opposite sides of the axis 0 and the acute-angled Vertices are close to the lens and touch the optical axis, and their surfaces 5 and in front of the lens in a common plane normal to the optical axis o those against the optical axis Inner surfaces 7 and 8 which are inclined in the direction of the lens 1 and converge in the direction of the lens 1 have a partial axis transparent / partially reflective coating, while the outer surfaces 9 and 10 are parallel to the surfaces 7 and 8 and have a totally reflective coating.

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In the triangular space between the surfaces 7 and 8, a three-sided prism 13 is inserted, which is cemented to the prisms 3 and 4 ο This results in partially transparent / partially reflective contact surfaces between fixed parts, i.e. between the three-sided prism 13 and the rhombic prisms 3 and 4, all of these prisms being made of glass with the same refractive index. " In the center of the prism 13, a cover screen 14 can be provided, which lies along the optical axis, in order to prevent ghosting of bright objects which lie directly behind the observer and are reflected into his eyes.

In this system, light from lens 1 enters prisms 3 and 4, with some light passing through the Inner surfaces 7 and 8 pass through while other light passes from these surfaces to the outer surfaces 9 and 10 is reflected. As a special example, a light beam R. emerges from the lens 1 on one side of the optical axis 0 and parallel to it with normal incidence through the surface 5 in

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the prism 3 and then hits the surface 7. The beam is _{split at the surface 7 into a transmitted beam R 2} , which runs parallel to the axis O, and a reflected beam R_, which moves to the surface 9. The beam R ₃ is totally reflected on the surface 9, strikes the surface 11 parallel to the surface 5 with normal incidence and then exits the prism parallel to the beam R ₂ . A beam R. exiting the lens 1 on the opposite side to and parallel to the optical axis passes in the same way through the surface 6 into the prism 4 and becomes a beam R ₅ , which passes through the surface 8, and a beam R _ß split, which is reflected on the surface 8 and then on the surface 10 to finally exit through the surface 12.

It can be seen that each eye of a binocular observer can see an enlarged infinite image that is produced by the lens 1 either by looking directly through the corresponding prismatic surfaces 7 or 8 (as indicated by the rays R ₂ and R ₅ ) and / or by indirect means Look through

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the corresponding prism surfaces 9 or 10 and 7 or 8 (as indicated by the rays R ₃ and R _g ) is generated o

In the embodiment of FIG. 2, the prism system 2 in front of the lens 1 contains two pairs of thombic prisms 15, 16 and 18, 19 made of glass of the same refractive index. The two prisms 15 and 16 on one side of the optical axis are cemented to one another on a contact surface 17, and the two prisms 18 and 19 on the opposite side of the axis are cemented to one another in the same way on a contact surface 20. The combination prisms 15/16 thus formed and 18/19 are arranged in substantially the same manner with respect to the lens 1 as the corresponding prisms 3 and 4 of FIG _o. 1 On the contact surfaces 17 and 20, which are provided in particular on the inner surfaces of the outer prisms 15 and 19, partially transparent / partially reflective layers are attached.The inner prism surfaces 21 and 22 and the outer prism surfaces 23 and 24 have totally reflective coatings

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The surfaces of the outer prisms 15 and 19 which face the lens 1, ie the surface 28 of the prism 15 and the corresponding surface of the prism 19, are matted and blackened in order to avoid reflection _{or the like}

This arrangement creates multiple light paths through which the light emerging from the lens 1 can be directed through the prism system 2 to an observer. For example, a light beam R 1, which emerges from the lens 1 on one side and parallel to the optical axis 0 and enters the prism 16 through its surface 25 under normal incidence, is totally reflected on the fleece 21 towards the contact surface 17 At the contact surface, the beam is split into a reflected beam R _Q , which exits through surface 26 of prism 16, and a transmitted beam Rg, which is totally reflected by surface 23 and exits through surface 27 of prism 15. A ray R. _Q which emerges from the lens 1 parallel to the optical axis and enters under normal incidence through the surface 25 of the prism 16,

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but at a point closer to the optical axis than the entry point of the ray R ₇ , the surface 21 is totally reflected towards the contact surface 17. The beam is split at the contact surface into a reflected beam R ₁₁ , which is guided back to the surface 21, and a transmitted beam R ₁₂ , ^which, however, is absorbed by the matted and blackened surface 28. The beam R ₁₁ is totally reflected back at the surface 21 to the contact surface, where it is _{split into a reflected beam R 13} which exits through the surface 26 of the prism 16 and a transmitted beam R _{14 which} is totally reflected by the surface 23 and exits through the surface 27 of the prism 15. Corresponding beams R ₁₅ and R _18, which emerge at opposite sides of the optical axis are directed in the same way in the konbinierten 18/19 prisms and emerge as rays R ₁₆ * ^R i7 ^"R 21 ^R 22 * ^una from.

In addition to the specially described light paths, there are further multiple reflections and Transmission paths on, so that a binocular

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Observer with either eye can see the enlarged infinite image passing through the lens 1 all these light paths is given

The embodiment of the Pig _o 3 is basically the same as that of FIG. 2, with the exception that the inner prismatic surfaces 21 and 22 have a coating that is partially transparent and partially reflective (in contrast to the totally reflective coating of the embodiment according to FIG The space between the surfaces 21 and 22 is filled with a three-sided prism 29 made of glass of the same refractive index as the prisms 16 and 18 with which it is cemented, and provided with a cover 30, as already described with reference to FIG With this arrangement, a light beam R ~ ₃ (which corresponds to light beam R ₇ of Fig. 2) is split at surface 21 (which has a partially transmissive and partially reflective interface between solid parts) into a transmitted one Ray R_-, which continues its path parallel to the optical axis to the observer, and a reflected one

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Ray R ₃₅ which passes through the contact surface in order to be partially transmitted and partially reflected, as already described with respect to the ray R ~ der Pig 2 *

A beam Rp ₆ (corresponding to the ray R ₁₅ of Figo 2} is split in the same way on the surface 22 (which is a partially transmissive / partially reflective interface between fixed parts having) in a transit transmitted beam R ₃₇ and a reflected beam Rpft "

A system according to the invention can, for example a converging magnifying lens 21 of approximately 10x magnification, but with a numerical one Orifice smaller than 1.0, the pinch system 2 being sufficient for binocular vision effective size, e.g. of about 80mm, and a combined vision of all enlarged Allows images of an object observed through the lens, as described above o

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This advantageously distinguishes the system from known binocular systems that have a have a maximum magnification power of about 5.5 times, because the necessary to achieve this magnification necessary focal length for the system is a numerical aperture of about 1.0 at an acceptable one Requires a magnification of approximately 80 mm

The lens 1 can have a relatively short focal length, e.g. on the order of 25 mm.

The embodiments of FIGS. 1, 2 and 3 can be provided with eye reliefs (eye reliefs) in the case of a prism system 2 of approximately 80 mm width (which are determined by the maximum distance at which the full field of view can be seen), which in the same or a similar way as the conventional beam splitter, additional— Lenses (relay-lens) and ocular-binocular systems are designed or provided in addition to these For the embodiments of FIGS. 1 and 3, the eye relief can be chosen up to 80 mm or more (although this is generally reduced when a shutter 14 or 30 is used).

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For the embodiment of Figure 2, the _o eye relief can be about 35 mm (The eye relief is also dependent on the area specified by the magnifying lens 1 field of view.).

The embodiments described produce an obvious one due to the multiple light paths Weakening of the image seen. This weakening is greatest for the embodiment of FIGS. 3 and can be remedied, for example, by a night vision device using a highly effective reinforcement tube will.

The one required for the collective magnifying lens 1 Collecting accuracy is generally about 0.5 Mi Iiradians, which is required so that there is no "jump" occurs in the image position because the eye closes over a different V7eg through the prism system 2 see begins.

Thus, the final image generated by the whole lens prism system comes to lie in an acceptable distance from the observer, a pair of weak plano-concave lenses are cemented (of suitable thickness) with the exit faces of the prisms _o This is in relation to the

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Figures 1, 2 and 3 in the embodiments of Pig _o 4A ₁ 4B and 4C illustrates, in which the plano-concave lenses 31 are cemented to the coplanar exit surfaces of the corresponding prisms. 4A shows a lens 31 attached to surface 11 of prism 3 and a similar lens 31 cemented to surface 12 of prism 4, lenses 31 extending over three-sided prism 13, as shown. 4B shows a lens 31 cemented to the coplanar surfaces 26 and 27 of the prisms 15 and 16 and a like lens 31 cemented to the corresponding coplanar surfaces of the prisms 18 and 19. Fig. 4C shows a lens 31 cemented to the exit surface of prisms 15 and 16 and a similar lens 31 cemented to the exit surfaces of prisms 18 and 19, the lenses 31 in this case extending over the three-sided prism 29 extend. The plano-concave lenses 31 are preferably cemented to the prisms in order to avoid problems due to "ghosting".

The rhombic prisms can conventionally have apex angles of 35 ° and 145 °, although different Angles can also be chosen provided that any "ghosting" problems are taken into account.

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It is desirable to matt or blacken the unused surfaces of the prisms to make them visible Preventing ghosting o In situations where backward bright lights are inside the Prisms can be reflected, it is also desirable to provide eye cups (eye guards).

If desired, the adjacent prism vertices can be bevelled sharply so that the Prisms are brought closer together, creating the required diameter of the magnifying converging lens is reduced · This is shown in Fig. 5, according to which at the points of contact of the prisms on the optical axis 0 bevels 32 are provided o

In general, it is desirable that the lens be slightly larger than the entrance surfaces of the prisms, to avoid "blind spots" in the oblique field of view o The lens should also be proportionate have little vignetting in order to avoid changes in brightness occurring in the field of view.

The maximum field of view of the system is essentially limited by the maximum opening that can be produced for the magnifying lens and can, for example, be greater than 60 °. The embodiment of Fig _o 3

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allows the largest field of view that can be produced (but there is also the greatest reduction in image brightness).

If desired, the system can have one or more deflections that are in the magnification collective— Lens can be attached, as illustrated in FIGS. 6, 7 and, for example.

In Fig. 6, the magnifying collective lens consists of two lens components 33 and 34, between which a 45 °, 90 ° and 45 ° prism 35 is attached. This prism has a totally reflective surface 36, which deflects the light path by 90 in a known manner. The light emerging from the lens component 34 is then received by the prism system 2.

In Fig. 7 is a rhombic prism 37 with totally reflective opposing surfaces 38 and 39 connected between the lens components 33 and 34 and generates a double deflection of the light path, thereby causing a lateral shift.

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In FIG _o 8 is a 45 °, 90 °, connected 45 ° prism 40 in the optical path between the lens components 33 and 34 and effected by the total reflective surfaces 41 and 42 of a double deflection, whereby a reversal with lateral displacement of the direction of the Light path is obtained "

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Claims (1)

PATENT CLAIMS Optical system for binocular vision, characterized in that one is an optical Axis (0) having magnifying collective lens (l) with the light reception from the lens causing means is combined, in which between fixed parts a pair partially permeable, partially reflective contact surfaces is provided, which are arranged on opposite sides of the optical axis and inclined to it, this Means a pair of reflective ones located on opposite sides of the optical axis Contain surfaces, each of which is farther from the optical axis than that partially transparent / partially reflective contact surface located on the same side, and parallel to a partially transmissive / partially reflective Contact surface is arranged so that it reflects light rays towards an observer, which they over the partially transparent / partially reflective contact surface of 6098 51/0797 - 23 - 2624U6 received by the lens parallel to light rays received by the lens and through the partially transparent / partially reflective contact surface get to the observer. 2ο Optical system according to claim 1, characterized characterized in that each reflection surface parallel to the partially transmissive / partially reflective interface is arranged on the same side of the q ± iseh axis, with the partially permeable / partially reflective contact surfaces are inclined against the optical axis and in the direction of the lens {1) conver- giereno Optical system according to Claim 1 or 2, characterized in that the reflective Surfaces are provided with a totally reflective coating o 4. Optical system according to one of the preceding claims, characterized in that the - 24 - 809851/0797 ₂₄ _ 262U46 partially transparent / partially reflective contact surfaces with a coating are provided with transparent / reflective properties. 5 · Optical system according to one of the preceding claims, characterized in that the means for receiving light from the lens of at least one pair of rhombic ones Prisms exist. 6. Optical system according to claim 5 »characterized in that a pair of rhombic prisms on opposite sides of the optical axis with the interposition of one three-sided prism is arranged, the contact surfaces between the three-sided Prism and the inner surfaces of the rhombic prisms associated with the optical axis are partially transparent / partially reflective. 7. Optical system according to claim 6, characterized in that the of the optical axis 609851/0797 - 25 - 262U46 r.iri the most distant outer surfaces of the rhombic prisms are totally reflective. S. Optical system according to claim 51 thereby Indicates that when using two pairs of rhombic prisms two each Prisms are arranged on one side and two on the other side of the optical axis, the two prisms on each side of the optical axis cemented together and the cemented contact surfaces are partially transparent / partially reflective are. 9 .. Optical system according to claim 8, characterized in that the outer surfaces of the outer Prisms, i.e. the surfaces furthest away from the optical axis, totally reflective are. 10. Optical system according to claim 8 or 9 »characterized in that the inner surfaces the inner prisms, i.e. those of the optical 609851/0797 - 26 - The surfaces lying next to the axis are totally reflective. llo optical system according to claim 8 or 9, characterized in that between the inner surfaces of the inner prisms, (doh surfaces lying next to the optical axis) a three-sided prism is used is, the contact surfaces between the three-sided prism and the inner Prisms are partially transparent / partially reflective. 12. Optical system according to one of claims 6, 7 and 11, characterized in that A cover panel is attached along the optical axis in the center of the three-sided prism is. 13 · Optical system according to one of Claims 5 to 12, characterized in that acute-angled Vertices of abutting prisms on opposite sides of the optical axis touch the optical axis. 609851/07 _ 27 - < lh. Optical system according to one of Claims 3 to 12, characterized in that abutting prisms on opposite sides of the optical axis have beveled vertices which touch the optical axis. 15 optical system according to claim 13 or 14, characterized in that the surfaces of abutting prisms located in front of the lens lie in the same plane. 16. Optical system according to one of claims 5 to 151, characterized in that with dttfr '.' ~ Outer surfaces of the rhombic prisms plano-concave lenses are united. 17. Optical system according to one of claims 5 to 16, characterized in that the unused surfaces of the rhombic prisms are matted and are blackened. 18. Optical system according to one of the preceding claims, characterized by means for kinking of the light path. 609851/0797 - 28 - 262U46 19 · Optical system according to claim 18, characterized characterized in that the means for kinking the light path consist of a prism kinking the light, the arranged in the light path between lenses enkoniponent en the magnifying converging lens are un cause one or more kinks in the light path penetrating the lens. 609851/0797