CN111948796A

CN111948796A - Lens device and method for manufacturing lens device

Info

Publication number: CN111948796A
Application number: CN202010410711.1A
Authority: CN
Inventors: M·格恩; P·利贝特劳特; S·施伦克尔
Original assignee: Xueli Optical Fiber Co ltd
Current assignee: Xueli Optical Fiber Co ltd
Priority date: 2019-05-16
Filing date: 2020-05-15
Publication date: 2020-11-17
Anticipated expiration: 2040-05-15
Also published as: DE102019112981B3; CN111948796B

Abstract

The invention relates to a lens device (1) for a rigid endoscope, comprising a tubular optics carrier (2), for example a system tube, and at least one lens (3), which is arranged in the optics carrier (2). The lens (3) is fixed within the optical component carrier (2) by means of at least one axial stop (10). The axial stop (10) is formed by deformation of the optical component carrier (2).

Description

Lens device and method for manufacturing lens device

Technical Field

The invention relates to a lens arrangement having at least one lens and a tubular optical component carrier, in which the lens is arranged.

Background

Such lens devices are known and are used, for example, in rigid endoscopes.

In the prior art, for example, system tubes are known as optical component carriers, into which one or more lenses are inserted. Between the lenses, so-called spacer sleeves are provided which hold the lenses in the desired position.

It has been found that the production of such a system pipe is very costly because, on the one hand, the spacer sleeve has to be produced with very high precision, but is very small in size and very thin-walled, and, on the other hand, because the spacer sleeve has to be pushed through the entire system pipe into its working position.

In the known lens arrangement, a further disadvantage is that the spacer sleeve shears the light path and thus vignetted the image.

Disclosure of Invention

It is therefore an object of the present invention to simplify the manufacture of a lens arrangement.

This object is solved by a lens arrangement according to claim 1 and a method according to claim 13.

According to the invention, the optical component carrier has at least one axial stop for the lens, wherein the stop is formed by at least one deformation of a wall of the optical component carrier.

The advantage of the invention is that the spacer sleeve can be completely dispensed with. This saves on the manufacturing costs of the spacer sleeve.

A further advantage of this configuration of the stop is that one end of the optical component carrier can always be considered as a reference line for the position of the stop. In this way, the tolerances inevitably present in the individual spacing rings do not add up. The position of a lens is not dependent on the position of an adjacent lens, but each lens is defined by the reference line. In principle, each lens therefore has the same and independent positional tolerances.

Another advantage is that there is no image vignetting based on the missing spacer sleeve.

Finally, it is advantageous if the wall in the region of the contact area of the lens body is not deformed. But only between the lenses. In this way no radial forces act on the lens and/or no stresses are formed in the lens body.

In one embodiment, it may be expedient to form axial stops before and after the lens, respectively, so that the lens is fixed in the axial direction of the optical component carrier.

In one embodiment, the stop is formed as a material edge of at least one region of the wall of the optical component carrier that is deformed inward in the use position. In this way, the position of the stop can be defined independently of the degree of deformation.

In one embodiment, the region to be deformed is delimited by two, in particular parallel, slits extending in the axial direction or in the circumferential direction at a distance from one another.

In order to maintain the stability of the optical device carrier, it is advantageous if the region to be deformed is delimited in the circumferential direction.

In one embodiment of the invention, the region to be deformed is connected to the remaining material of the optical component carrier at both ends of the slot. The slits thus define tabs which are inwardly deformable or deformed. In this embodiment, the slot is preferably oriented in the circumferential direction, so that the edge defined by the slot forms a stop.

In a further embodiment of the invention, the region to be deformed is connected to the remaining material of the optical component carrier only at one end of the slot. The slits thus define tongues which are inwardly deformable or deformed. In this embodiment, the two parallel slots can be oriented axially or circumferentially, since in each case one defined slot edge forms a stop.

In an advantageous embodiment, the stop is formed by at least two, preferably at least three, circumferentially distributed, in particular uniformly distributed, regions to be deformed. In this way, with a simultaneously stable optical device carrier, lenses can be arranged efficiently.

In this case, it can be advantageous if the regions of the different stops are arranged offset from one another in the circumferential direction, i.e., rotationally offset. The stability of the optical device carrier can thereby be improved.

Axial stop requirement: the lenses are placed one after the other in the optical device carrier. The stops must be produced in steps before and/or after the insertion of the lens.

In an advantageous alternative embodiment, the region to be deformed is deformed outwardly in the production position of the optical component carrier and inwardly in the use position.

In this way, an optical component carrier can be produced which already has all the regions to be deformed. This deformation is carried out after the lens has been inserted in order to form a stop.

In one embodiment, the regions are pressed inward in such a way that the optical component carrier is pushed into the enveloping system tube.

In a further embodiment, in the area of the lens body, in the use position of the lens, a fastening opening is formed in a wall of the optical component carrier, through which fastening opening a material-locking fastening of the lens is formed or can be formed. In this way, the lens can be fixed in its position, for example with an adhesive or by welding. Since the fixing openings are shown on the circumference of the lens body, fixing is possible without the risk of, for example, adhesive entering the field of view of the lens.

In one embodiment, the optical device carrier has at least one lens holder. The lens holder may have a stopper portion for an axial direction of the lens. Such a lens holder is integrated in or connected to the optical component carrier. The lens holder can be formed, for example, by a circumferential edge in the inner circumference of the optical component carrier or by one or more projections. Preferably, the lens holding portion is not formed by deformation of the optical device carrier.

In an expedient embodiment, the at least one lens is arranged coaxially in the optical component carrier. In this way, the axial orientation of the plurality of lenses can be realized particularly simply, as a result of which the lens arrangement can be produced more simply and more inexpensively.

Preferably, the optics carrier is designed as a system tube and can be used in an endoscope in this way.

In one embodiment, the optics carrier can be placed in a system tube, in particular an endoscope.

It is expedient if the optical component carrier is made of metal (in particular if it is used as a system tube) or plastic.

The method according to the invention for producing a lens arrangement with an optical component carrier and at least one lens is characterized in that the optical component carrier is deformed in order to form an axial stop for the lens.

It is advantageous here that the wall in the region of the lens body that bears against it is not deformed. But only axially between the lenses. In this way no radial forces act on the lens and/or no stresses are formed in the lens body.

In one embodiment, for each lens, the stop is produced by deformation of the wall before and/or after the lens is inserted. In this way, the arrangement of the lenses in the lens arrangement can be processed in sequence. Depending on the distance of two adjacent lenses, one stop may be used for both lenses. However, two stops can also be formed when the distance between the two lenses is large.

In one embodiment, the stop is produced by an inwardly directed thermoplastic or plastic deformation of a region of a wall of the optical component carrier. The material of the optical component carrier can be relied upon here, by means of which deformations can be produced.

In one embodiment, the stop is formed by a material edge of at least one region of the wall of the optical component carrier which is deformed inward in the use position. Such a material edge has the advantage that the axial position can be determined more precisely.

It is expedient if the region to be deformed can be delimited in the circumferential direction.

In one embodiment, the deformation region is formed by two, in particular parallel, slits extending in the axial direction or in the circumferential direction at a distance from one another.

The slots can be introduced in different ways, for example by milling or drilling. However, it is particularly advantageous if the slits are produced by laser cutting or etching.

The region defined by the slit may be deformed inwardly in order to form a stop.

In one embodiment, first all slits for all regions to be deformed are introduced into the optical component carrier. They are then deformed in turn before and/or after the lens is inserted.

In one embodiment, the region to be deformed is connected to the remaining material of the optical component carrier only at one end of the slot. The tongue thus formed can be deformed inwards in order to form a stop.

In one embodiment, the region to be deformed is connected to the remaining material of the optical component carrier at both ends of the slot. The tabs so formed may be deformed inwardly.

In principle, one stop can be formed by only one deformation region. However, it is expedient if a stop is formed by at least two, preferably at least three, circumferentially distributed, in particular uniformly distributed, regions to be deformed.

In one embodiment, the region to be deformed is deformed outward in the production position of the optical component carrier. Before and/or after the insertion of the lens, said regions can be deformed inwardly in order to form stops for the lens. It is possible here for the deformation to be elastic in the inward direction, so that disassembly is also possible.

In particular, the region is deformed inward by introducing the optical component carrier into the enveloping tube. The regions are pressed through the tube from the outside to the inside. In this case, it is possible for the enveloping tube to be made of a different material than the optical component carrier.

In one embodiment, the deformation is produced by means of a special tool which loads the circular tube wall of the optical component carrier from the radially outside.

In one embodiment, the optic carrier is made of plastic. The deformation can also be carried out by point-by-point or targeted heat input or supply.

In another embodiment, the optic carrier may be made of a shape memory alloy, particularly a metal. The deformation can be carried out by a targeted or overall heat treatment.

Drawings

The invention will be explained in detail below with the aid of the figures according to preferred embodiments.

Wherein:

figure 1 shows a lens arrangement according to the prior art,

figure 2 shows a part of a longitudinal section of a lens arrangement according to the invention,

figure 3 shows a top view of the lens arrangement of figure 2,

figure 4 shows a side view of the lens arrangement of figure 2,

figure 5 shows an oblique view of another lens device according to the invention with a fixed opening,

figure 6 shows a part of a longitudinal sectional view of the lens arrangement of figure 5,

figure 7 shows a top view of the lens arrangement of figure 5,

figure 8 shows a detail of a longitudinal section through a lens arrangement according to the invention with two additional lens receptacles,

figure 9 shows a part of a longitudinal sectional view of a lens arrangement according to the invention with an enveloping system tube,

figure 10 shows a part of a longitudinal sectional view of a lens arrangement according to the invention with an enveloping system tube,

fig. 11 shows a side view of a system pipe according to the invention for elucidating tolerance dimensions, an

Fig. 12 shows a flow chart of a method according to the invention.

Detailed Description

Fig. 1 shows a lens arrangement 1 according to the prior art. The lens device 1 has an optical component carrier 2, which is designed here as a system tube. The optical component carrier 2 is tubular. Three lenses 3 are arranged in the optical component carrier 2, wherein a spacer ring 4 is arranged between the lenses 3, around which spacer ring the axial position of the lenses 3 is defined. The rod lens is here exemplarily formed as lens 3, but the invention is applicable without exception to all lens forms.

The position of the third lens 3 is obtained by adding the sizes L1 to L4, for example. It is clear from this that the tolerances of the lengths of the spacer ring 4 and the lens 3 are accumulated. It is almost impossible to determine the absolute position of the lens. Thereby generating aberrations.

Also in the following embodiments, the lenses 3 are shown as rod lenses, respectively. However, the present invention is not limited to rod lenses in any way. However, the form of the lens is not important to the present invention. Rather, the teachings of the present invention can be used in all lens forms without modification.

Fig. 2 to 4 show a lens device 1 according to the invention with a tubular optical component carrier 2. Although only one lens 3 is shown in the illustrated part, a plurality of lenses 3 may be present. According to the invention, the optical device carrier 2 has a deformable region 5 in the form of an inwardly deformed tongue. As can be seen in fig. 4, the region 5 to be deformed is defined by two parallel axially oriented slits 6. The region 5 to be deformed has an additional slit 7 extending in the circumferential direction at one end of the axial slit 6. The region 5 to be deformed is thereby connected to the wall 8 of the optical component carrier 2 at only one end. The tongues 9 thus formed are deformed inwards.

The cut edge of the circumferentially extending slit 7 of the tongue 9 forms an axial stop 10 for the lens 3. Preferably, the lens 3 is coaxially arranged in the optical device carrier 2. This can be ensured, for example, by the diameters of the lens 3 and the optics carrier 2 being optimally matched to one another, i.e. the diameter of the lens is only slightly smaller than the inner diameter of the optics carrier 2. Since the lens 3 therefore does not fall over, such a tongue 9 is sufficient as a stop 10.

The coaxial arrangement of the lenses 3 has the additional advantage that: the optical axes of the respective lenses 3 coincide with each other. Thereby reducing optical aberrations.

In this embodiment, however, it is also easily possible to provide a plurality of, in particular two or three, stops for the lenses, which are distributed uniformly over the circumference.

Fig. 5 to 7 show a second lens arrangement 1 according to the invention. The optical component carrier has an axial stop 10 for the lens 3. The stop is, however, formed by three regions 5 to be deformed, which are distributed uniformly over the circumference. Each region 5 to be deformed is delimited by two parallel slots 7 extending in the circumferential direction. This forms an inwardly bent web 11 in each case. As can be seen in fig. 7, the cut edge of the slot 7 forms an axial stop 10.

The optical component carrier 2 has, however, in addition a fastening opening 12 in the wall 8. The fixing opening 12 is axially spaced apart from the stop 10 and is located in the region of the lens body of the lens. In this example, an adhesive 13 is introduced into the fastening opening 12, which adhesive forms a cohesive connection with the outer circumference of the lens 3.

Even in this embodiment, the number of stops is not mandatory, but can vary. By an optimal matching of the diameters of the lens 3 and the optics carrier 2, the lens 3 is coaxially oriented even in this embodiment. There is thus no risk of tipping over, so that even only one stop would be sufficient.

Fig. 8 shows a lens arrangement 1 similar to that of fig. 6, with three lenses 3. In this embodiment, the optical component carrier 2 has a first lens receptacle 14 which is formed by a circumferential first edge 15_1 on the inner circumference of the optical component carrier 2 and forms an axial stop for the first lens 3_ 1. The optical component carrier 2 has a second lens receptacle 14 for the second lens 3_2, which is likewise formed by a second edge 15_2 that surrounds the inner circumference of the optical component carrier 2, but the diameter of the first edge 15_1 is smaller than the diameter of the second edge 15_ 2.

An axial stop 10 according to the invention is formed between the second lens 3_2 and the third lens 3_3 by deforming the optical component carrier 2. The second lens 3_2 and the third lens 3_3 bear axially against the stop 10. The third lens 3_3 is fixed here as in fig. 6 by means of an adhesive 13 through a fixing opening.

In fig. 8 it is again clearly visible that the lens 3 is arranged coaxially with the optics carrier 2. The three optical axes of the lens thus coincide with the axis 17 of the optics carrier 2. Thereby, aberrations caused by misalignment of the lens 3 can be avoided at least.

In all the embodiments shown so far, the lenses 3 are preferably inserted into the optical component carrier 2 step by step and in succession. In front of and/or behind each individual lens, the respective stop is then first formed by deformation. Only after this is the other lens processed. All regions to be deformed 5 can be produced first by the slits. The actual deformation is however performed sequentially.

Fig. 9 shows a lens arrangement 1 according to the invention with an optics carrier 2 and in this example three lenses 3.

The optical component carrier 2 has three stops 10, which are each formed by a deformable region 5. In the embodiment shown, the deformable region 5 is formed as a web 11 by two slits 7 extending in the circumferential direction. In this case, however, the webs 11 are initially deformed outward in the production position, wherein the webs 11 have a convex shape in this example.

In this production position, all lenses 3 can be inserted first. The deformation of the tabs 11 is achieved in this embodiment by pushing the optics carrier 2 into the enveloping tube 16 of the endoscope, for example the system tube.

Figure 9 shows the enveloped tube 16 of the half push sleeve. As can be seen from this, the ends of the enveloping tube 16 press inwards against the outwardly projecting tabs 11. Here, the tab 11 is folded from its convex shape to its concave shape. The axial stop 10 is formed by one of the circumferentially extending slot edges of the web.

Fig. 10 shows a lens device 1 similar to fig. 9. The region 5 to be deformed is however designed as a tongue 9 which engages only on one side. The tongue has an outward plastic deformation. Said deformation ensures that the tongues 9 are elastically bent inwards by pushing into the enveloping tube 16. The circumferentially extending slit edge then forms a defined stop 10 for the lens.

Fig. 11 shows a lens device 1 having two deformable regions 5 which are each formed by two slits 7 extending in the circumferential direction. The stops 10 are each delimited by a gap edge. The advantage of the invention is that the two stops 10 are fixed with respect to one end of the optical component carrier 2. Possible tolerances in the dimensions L6 and L7 are therefore the same and independent of the position and number of lenses 3. The tolerances thus always act only on the respective lens 3 and not on the other lenses when the deformable region 5 is produced or when the deformation itself occurs. Each lens 3 is thus absolutely fixed with respect to the optical device carrier. Aberrations, which are generated by incorrect lens spacings, can thereby be avoided.

In principle, a material-locking fixation of the individual lenses 3 can always be possible and can be independent of the deformed embodiment.

Fig. 12 shows a flow chart of the method according to the invention. In an optional first step S1, all regions to be deformed 5 are first established in the optical device carrier. Depending on the application, this step can be dispensed with.

In the placing step S2, the lens is first placed in the optical device carrier. An axial stop for the lens is then produced in a deformation step S3 by deforming the respective deformable region. Depending on the application, the deforming step S3 may also be performed before the step S2 is performed.

It is then tested in a test step S4 whether all lenses have been placed in the optical device carrier. If so, the method ends in S5. Otherwise, optionally proceed to step S2 or deformation step S3.

List of reference numerals

1 lens device

2 optical device carrier

3 lens

4 spacer ring

5 deformable area

6 axially oriented slits

7 slits extending in circumferential direction

8 wall

9 tongue piece

10 axial stop

11 contact piece

12 fixed opening

13 adhesive

14 lens housing part

15 surrounding edge

16 enveloped tube

17 axis of rotation

18 deformation part

S1 producing a region to be deformed

S2 embedding step

S3 deforming step

S4 test procedure

S5 ends

Claims

1. Lens arrangement (1) having at least one lens (3) which is arranged in a tubular optics carrier (2), characterized in that the optics carrier (2) has at least one axial stop (10) for the lens (3), wherein the stop (10) is formed by at least one deformation of a wall (8) of the optics carrier (2).

2. Lens arrangement (1) according to claim 1, characterized in that the stop (10) is formed as a material edge of at least one region (5) of the wall (8) of the optical component carrier (2) which is deformed inward in the use position.

3. Lens device (1) according to one of the preceding claims, characterized in that the region (5) to be deformed is delimited in the circumferential direction.

4. Lens device (1) according to one of the preceding claims, characterized in that the region (5) to be deformed is delimited by two, in particular parallel, slits (6, 7) extending in the axial direction or in the circumferential direction at a distance from one another.

5. A lens device (1) as claimed in claim 4, characterized in that the region (5) to be deformed is connected to the remaining material of the optical component carrier (5) at one or both ends of the slits (6, 7), respectively.

6. Lens arrangement (1) according to one of the preceding claims, characterized in that the stop (10) is formed by at least two, preferably at least three, circumferentially distributed, in particular uniformly distributed, regions (5) to be deformed or deformed.

7. Lens device (1) according to one of the preceding claims, characterized in that the region (5) to be deformed is deformed outwardly in the production position of the optics carrier (2) and inwardly in the use position, which can be reached or is reached, in particular, by placing the optics carrier (2) in the enveloping tube (16).

8. Lens arrangement (1) according to one of the preceding claims, characterized in that in the region of the lens body in the use position of the lens body there is formed a fixing opening (12) in the wall (8) of the optical component carrier (2), by means of which fixing opening a cohesive fixing of the lens has been formed or can be formed, in particular by means of an adhesive (13).

9. Lens arrangement (1) according to one of the preceding claims, characterized in that the optics carrier (2) has at least one lens holder (14), in particular the lens holder is formed by at least one projection or edge (15) on the inner circumference of the optics carrier (2).

10. Lens arrangement (1) according to one of the preceding claims, characterized in that the lens (3) is arranged coaxially in the optical component carrier (2).

11. Lens device (1) according to one of the preceding claims, characterized in that the optical component carrier (2) is constructed as a system tube or can be inserted into a system tube (16).

12. Lens device (1) according to one of the preceding claims, characterized in that the optical component carrier (2) is made of metal or plastic.

13. Method for manufacturing a lens arrangement (1), in particular according to one of the preceding claims, having an optics carrier (2) and at least one lens (3), characterized in that the optics carrier (2) is deformed (S3) in order to form an axial stop (10) for the lens (3).

14. Method according to claim 13, characterized in that a stop (10) is produced for each lens (3) by deformation of the wall (8) before and/or after insertion of the lens (3).

15. Method according to claim 13 or 14, characterized in that the stop (10) is produced by an inwardly directed thermoplastic, plastic or elastic deformation of the region (5) of the wall (8) of the optical component carrier (3).

16. Method according to one of claims 13 to 15, characterized in that the stop (10) is formed by a material edge of at least one region (5) of the wall (8) of the optical component carrier (2) which is deformed inward in the use position.

17. Method according to one of claims 13 to 16, characterized in that the region (5) to be deformed is delimited in the circumferential direction.

18. Method according to one of claims 13 to 17, characterized in that the deformed region (5) is formed by two, in particular parallel, slits (6, 7) extending in the axial direction or in the circumferential direction at a distance from one another, in particular the slits (6, 7) being produced by laser cutting or etching.

19. Method according to one of claims 13 to 18, characterized in that the region (5) to be deformed is connected to the remaining material of the optical component carrier (2) at one or both ends of the slot (6, 7) respectively.

20. Method according to one of claims 13 to 19, characterized in that the axial stop (10) is formed by at least two, preferably at least three, circumferentially distributed, in particular uniformly distributed, regions (5) to be deformed.

21. Method according to one of claims 13 to 20, characterized in that the region (5) to be deformed is deformed outwardly in a production position of the optical component carrier (2) and inwardly in a use position, in particular the production position is transferred into the use position by placing the optical component carrier (2) into the enveloping tube (16).