Optical Machines

Abstract

To provide a small-sized optical instrument that can stably guide the movement of a pair of lenses.SOLUTION: An optical instrument has: a pair of lenses L2L, L2R that are arranged separated from each other in a first direction and movable in a second direction; a male screw member 14 that is rotatable at a fixed position in the second direction; a rotational operation member 13 that is rotationally operated by a user to rotate the male screw member; a female screw member 16 that is screwed with the male screw member and is moved in the second direction with respect to a base member 12 in conjunction with the rotation of the male screw member; and moving members 3, 17 that hold the pair of lenses and move in the second direction together with the female screw member. The male screw member and the female screw member are screwed with each other to guide the movement of the moving members in the second direction. The optical instrument has guide parts that guide the movement of the moving members in the second direction, at positions where a second plane including the central axis of the male screw member passes orthogonal to a first plane including the respective optical axes of the pair of lenses, or at positions along the second plane.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an optical instrument such as a pair of lenses, such as a pair of binoculars. [Background technology]

[0002] In the optical device as described above, a mechanism is provided in which a pair of left and right lenses are held integrally by a moving member and the moving member is moved by rotating a screw member so that there is no difference in the amount of movement when the pair of left and right lenses are moved in the optical axis direction during focusing, etc. In this mechanism, as also disclosed in Patent Document 1, linear guide parts for guiding the moving member in the optical axis direction without backlash to the left and right are provided in front of the screw member (on the object side) at multiple locations separated from each other in the optical axis direction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4054405 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if a plurality of linear guide portions are disposed apart from one another in the optical axis direction, it is difficult to reduce the size of the optical device in the optical axis direction.

[0005] The present invention provides an optical device that is compact and that stably guides a moving member that holds a pair of lenses in the optical axis direction. [Means for solving the problem]

[0006] An optical device according to one aspect of the present invention is an optical device having a pair of lenses arranged apart from each other in a first direction and movable in a second direction perpendicular to the first direction, and includes a base member, a first screw member rotatable at a fixed position in the second direction, a rotation operating member that is rotated by a user to rotate the first screw member, a second screw member that screws into the first screw member and moves in the second direction relative to the base member as the first screw member rotates, and a movable member that holds the pair of lenses and moves integrally with the second screw member in the second direction. A guide portion is provided which includes a guide groove portion provided in the moving member and a guide member provided in the base member and engages with the guide groove portion, and which guides the movement of the moving member in a second direction relative to the base member. The guide portion is disposed on a second plane which is perpendicular to a first plane which includes the optical axes of the pair of lenses and which includes the central axis of the first screw member, between the central axis of the first screw member and the first plane. A holding portion is provided at a position away from the guide portion in the first direction, which guides the movement of the moving member in the second direction and holds the moving member to the base member. is. The holding portion is In the second direction The guide portion is disposed on the rotating operation member side. When viewed from a direction perpendicular to the first plane, at least a part of the guide portion is disposed in a region overlapping with the pair of lenses in the second direction. It is characterized by: Effect of the Invention

[0007] According to the present invention, it is possible to realize a compact optical device in which a moving member that holds a pair of lenses is stably guided in the optical axis direction. [Brief description of the drawings]

[0008] [Figure 1] 1 is a perspective view showing the appearance of binoculars (optical apparatus) according to an embodiment of the present invention. [Diagram 2] FIG. [Diagram 3] FIG. 3 is a cross-sectional view of the binoculars of FIG. [Figure 4] FIG. 3 is a cross-sectional view of a focus mechanism in the binoculars. [Diagram 5] FIG. [Figure 6] FIG. [Figure 7] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 shows the appearance of binoculars as an optical instrument according to an embodiment of the present invention. The binoculars have a pair of left and right objective optical systems, a pair of left and right erecting optical systems, and a pair of left and right eyepiece optical systems. In this embodiment, left and right correspond to the left eye and right eye observing the binoculars, respectively. In this embodiment, the object side observed by the binoculars is also called the front side, and the observer (user) side is also called the rear side.

[0010] In FIG. 1, the optical axis OL of the left objective optical system and the optical axis OR of the right objective optical system are parallel to each other. FIG. 1 shows a state in which the distance between the optical axis OL and the optical axis OR is the same as the distance between the optical axis EL of the left eyepiece optical system and the optical axis ER of the right eyepiece optical system. In the following description, the optical axes OL and OR of the objective optical systems are referred to as the objective optical axis, and the optical axes EL and ER of the eyepiece optical systems are referred to as the eyepiece optical axis. The direction in which the optical axes OL and OR (EL and ER) are spaced apart is referred to as the left-right direction (first direction), and the direction in which each optical axis extends is referred to as the optical axis direction (second direction). In the directions perpendicular to the optical axis direction and the left-right direction, the upper side of the binoculars in the upright position as shown in FIG. 1 is referred to as the upper side, and the lower side is referred to as the lower side.

[0011] The front cover 31 houses the left and right objective optical systems and holds the left and right protective glasses L1L, L1R at its front end. The main body 10 is integrated with the front cover 31 by screws (not shown), and houses a focus mechanism and an interpupillary distance adjustment mechanism (described later), and supports the left and right eyepiece units 9L, 9R, each of which includes an erecting optical system and an eyepiece optical system.

[0012] Figure 2 shows the optical and mechanical configurations on the left side when the binoculars in the state shown in Figure 1 are cut along a plane including the objective optical axis OL and the eyepiece optical axis EL. Here, the optical and mechanical configurations on the left side will be explained, but the optical and mechanical configurations on the right side are the same, and some of the components on the left side that have reference characters ending in L are given reference characters ending in R in parentheses to indicate that they are components on the right side.

[0013] The objective optical system is composed of a protective glass L1L and an objective lens L2L. The erecting optical system is composed of a Polo II prism L3L. The eyepiece optical system is composed of an eyepiece lens L4L.

[0014] The front lens barrel 1L holds an objective lens L2L, which is held by a fixed barrel 2L via an eccentric roller (not shown). The fixed barrel 2L is attached to an objective table 3, and is fixed to an objective lens L2L so as to be perpendicular to the objective optical axis OL. Mounting Surface 3a with screws 4. The front lens barrel 1L has its parallel decentering and inclination adjusted with respect to the fixed barrel 2L so that the objective optical axis OL coincides with the eyepiece optical axis EL via the Polo II prism L3L by the rotation of the decentering rollers.

[0015] In the eyepiece unit 9L, the eyepiece tube 5L holds the eyepiece lens L4L. The prism holder 6L holds the Polo II prism L3L. The eyepiece holder 7L holds the eyepiece tube 5L. The prism holder 6L and the eyepiece holder 7L are integrated with screws so that the Polo II prism L3L and the eyepiece lens L4L are positioned in a predetermined positional relationship. The holding mechanism and adjustment mechanism for the Polo II prism L3L will be described later.

[0016] The rubber eyecup 8L covers the eyepiece tube 5L. The observer places his / her face against the rubber eyecup 8L to observe an object. To connect the eyepiece tube 5L to the eyepiece holder 7L, a male helicoid thread is formed on the outer peripheral wall of the eyepiece tube 5L, and a female helicoid thread is formed on the inner peripheral wall of the eyepiece holder 7L. Diopter adjustment is possible by rotating either the left eyepiece tube 5L or the right eyepiece tube (not shown) around the eyepiece optical axis and moving it in the optical axis direction.

[0017] The main body 10 supports the left and right eyepiece units 9L, 9R rotatably around the objective optical axes OL, OR, respectively, and also supports a focus mechanism that moves the left and right objective lenses L2L, L2R in the optical axis direction to perform focusing according to the observation distance. The main body 10 is made of metal because it requires high rigidity and precision. The main body 10 is formed with an opening 10L coaxial with the left objective optical axis OL, and an opening (not shown) coaxial with the right objective optical axis OR. A cylindrical portion 6La provided on the left prism holder 6L is rotatably fitted into the left opening 10L, and a cylindrical portion of the left prism holder is rotatably fitted into the right opening as well.

[0018] Fig. 3 shows a cross section of the binoculars taken along line III-III in Fig. 2, illustrating the interpupillary distance adjustment mechanism. The left and right interlocking plates 11L, 11R are connected to the peripheral portions of the cylindrical portions 6La, 6Ra of the prism holders 6L, 6R with screws, respectively, and can rotate integrally with the prism holders 6L, 6R, and have gear portions 11La, 11Ra for interlocking the rotation of the prism holders 6L, 6R with each other. The interlocking plates 11L, 11R also have a number of arms 11Lb, 11Rb, respectively, that generate a biasing force in the optical axis direction. The arms 11Lb, 11Rb sandwich the main body 10, generating a biasing force to press the prism holders 6L, 6R against the main body 10.

[0019] The gears 11La and 11Ra mesh with each other, allowing the rotation of the left and right eyepiece units 9L (6L, 7L) and 9R (6R, 7R) to be linked with each other. The eyepiece optical axes EL and ER are decentered by a predetermined amount with respect to the objective optical axes OL and OR by the left and right Polo II prisms L3L and L3R, respectively, so that the distance between the eyepiece optical axes EL and ER changes when the eyepiece units 9L and 9R rotate. This makes it possible to adjust the pupil distance to match the distance between the eyepiece optical axes EL and ER to the distance between the observer's left and right eyes.

[0020] Fig. 4 shows a cross section of the focusing mechanism taken along line IV-IV in Fig. 3, and Fig. 5 shows the entire focusing mechanism. Fig. 6 shows the focusing mechanism in an exploded view. The objective base member 12 is fixed to the main body 10 with screws (not shown). As described above, the focusing plate 17 is connected to the objective stage 3 that holds the objective lenses L2L and L2R via the fixed cylinders 2L and 2R. The focusing plate 17 and the objective stage 3 are movable members that are supported and guided by a guide mechanism (described later) relative to the objective base member 12 so as to be movable in the optical axis direction.

[0021] The rear end wall portion 17c of the focus plate 17 is bent upward, and an opening is formed in the rear end wall portion 17c. (First screw member) A feed screw 14 serving as a rotation operation member is inserted so as to extend in the optical axis direction. A focus operation dial 13 serving as a rotation operation member is connected to the rear end of the feed screw 14 by a screw 15 so as to be rotatable together with the feed screw 14. The focus operation dial 13 and a stopper plate 25 attached near the front end of the feed screw 14 sandwich the main body 10, thereby preventing movement of the focus operation dial 13 and the feed screw 14 in the optical axis direction. This allows the focus operation dial 13 and the feed screw 14 to rotate at fixed positions in the optical axis direction.

[0022] A female screw member that is disposed on the outer periphery of the feed screw 14 and has a female screw portion that screws into the male screw portion of the feed screw 14 (Second screw member)The drive nut 16 serving as the focus plate 17 is fixed to the focus plate 17 with a screw 18. When the observer rotates the focus operation dial 13 to rotate the feed screw 14, the drive nut 16 is driven in the optical axis direction by the screw-in action of the drive nut 16 and the feed screw 14, and the focus plate 17 and the objective stage 3 move in the optical axis direction. As a result, the left and right objective lenses L2L, L2R move in the optical axis direction, and focusing according to the observation distance is performed.

[0023] As described above, the objective stage 3 has an objective mounting surface 3a formed so as to be perpendicular to the objective optical axes OL and OR, and further has a focus mounting surface 3b parallel to the objective optical axes OL and OR above the objective mounting surface 3a. Focus connectors 3c protruding upward are provided on both the left and right sides of the focus mounting surface 3b. The focus connectors 3c are inserted into elongated holes 12a formed on both the left and right sides of the objective base member 12 so as to extend in the optical axis direction, and are connected to the focus plate 17 by screws 19. The objective base member 12 has a sliding surface 12b parallel to the O plane as a first plane including the objective optical axes OL and OR.

[0024] A guided groove portion 17a is formed in one location in the optical axis direction in a portion of the focus plate 17 forward of the feed screw 14, i.e., at a position (or a position along the F surface) that is perpendicular to the O surface and that serves as a second surface including the center axis of the feed screw 14. On both the left and right sides of the guided groove portion 17a sandwiching the F surface, guided surfaces that extend in the optical axis direction along the F surface are formed. A guide shaft portion of a guide member 20 is fitted into the guided groove portion 17a. On the left and right sides of the guide shaft portion, guide surfaces that come into line contact or surface contact with the left and right guided surfaces of the guided groove portion 17a are formed. At this time, the guide shaft portion may be press-fitted into the guided groove portion 17a.

[0025] The guide member 20 is fixed to the objective base member 12 by screws 22, with a leaf spring 21 serving as an elastic member having a rectangular frame shape sandwiched between the guide member 20 and the focus plate 17. The guide member 20 and the guided groove portion 17a form a guide portion.

[0026] Further, through grooves 17b extending in the optical axis direction are formed in the left and right rear portions of the focus plate 17 that are separated from the guided groove portion 17a on both sides in the left-right direction and overlap with the area in the optical axis direction where the feed screw 14 is provided. The shaft portion of the holding member 26 is inserted into each through groove portion 17b. A gap is provided between the shaft portion of the holding member 26 and the two surfaces on both the left and right sides of the through groove portion 17b. The holding member 26 is fixed to the objective base member 12 by screws 23, with a leaf spring 21 sandwiched between the holding member 26 and the focus plate 17. As a result, the objective base member 12 and the holding member 26 hold the focus plate 17 movably in the optical axis direction. The holding member 26 and penetration The groove portion 17b constitutes a holding portion.

[0027] Each leaf spring 21 generates a biasing force that presses the focus plate 17 against the sliding surface 12b of the objective base member 12. As a result, the focus plate 17 always slides on the sliding surface 12b during focusing.

[0028] The material of the feed screw 14 is metal, and the material of the drive nut 16 is resin. The thread pitch of the female thread of the drive nut 16 is set slightly smaller than the thread pitch (lead) of the male thread of the feed screw 14. As a result, the male thread of the feed screw 14 and the female thread of the drive nut 16 are screwed together in a press-fit state. For example, the thread pitch of the feed screw 14 is 4.65 mm, while the thread pitch of the drive nut 16 is 4.50 mm. Since the thread pitches of the feed screw 14 and the drive nut 16 are different from each other in this way, the inclined surface of the thread of the feed screw 14 and the inclined surface of the thread of the drive nut 16 are pressed into contact with each other. At this time, the thread of the resin drive nut 16 is slightly deformed by the thread of the metal feed screw 14. As a result, the drive nut 16 not only converts the rotation of the feed screw 14 into a movement in the optical axis direction with almost no backlash in either the optical axis direction or the left-right direction, but is also guided in the optical axis direction by the feed screw 14. That is, the movement of the focus plate 17 integrated with the drive nut 16, the objective stage 3, and the left and right objective lenses L2L, L2R in the optical axis direction is guided.

[0029] If the thread pitch of the feed screw and the drive nut were the same, it would be possible to convert the rotation of the feed screw into movement in the optical axis direction, but the drive nut would not be able to be guided in the optical axis direction due to a certain amount of play in the left-right direction.

[0030] On the other hand, in this embodiment, the movement of the focus plate 17, the objective table 3, and the left and right objective lenses L2L, L2R in the optical axis direction is guided by the engagement of the guide portion (the guide member 20 and the guided groove portion 17a) described above. That is, the movement of the focus plate 17, the objective table 3, and the left and right objective lenses L2L, L2R in the optical axis direction is guided at two points, the position of the drive nut 16 and the position of the guide portion, which are separated from each other in the optical axis direction. This makes it possible to reduce backlash in the left and right direction of the focus plate 17, the objective table 3, and the left and right objective lenses L2L, L2R, compared to the case where only the drive nut 16 is guided by the feed screw 14.

[0031] Furthermore, by providing the leaf springs 23 at positions away from the guide groove portions 17a on both the left and right sides, it is possible to prevent the focus plate 17, the objective table 3 and the left and right objective lenses L2L, L2R from displacing in a direction perpendicular to the objective optical axes OL, OR as the posture of the binoculars changes, thereby preventing the objective optical axes OL, OR from displacing.

[0032] 7 shows a view from above. As shown by hatching in this figure, the guide member 20 arranged in front of the feed screw 14 is arranged in a region where at least a part of it overlaps with the objective lenses L2L, L2R in the optical axis direction when viewed from above. This shortens the length of the focus mechanism in the optical axis direction, and also shortens the length of the feed screw 14 arranged to protrude upward from the O surface in the optical axis direction.

[0033] With the above configuration, it is possible to realize a compact pair of binoculars in which the left and right objective lenses L2L, L2R can be stably moved in the direction of the optical axis.

[0034] In this embodiment, the guide portion is formed by the guided groove portion 17a and the guide member 20, but a guide portion of another configuration may be used as long as it has a guide function in the optical axis direction. The same applies to the holding portion formed by the through groove portion 17b and the holding member 26.

[0035] In this embodiment, the leaf springs 21 are disposed in the guide portions (17a, 20) and the holding portions (17b, 23), but they may be disposed in other positions.

[0036] Furthermore, in this embodiment, the case where only one guide portion is provided at one location forward of the feed screw 14 in the optical axis direction has been described. However, it is also possible to arrange two or more guide portions side by side in the left-right direction at the above-mentioned one location. For example, two guide portions may be provided along (sandwiched between) the F surface at the same location in the optical axis direction.

[0037] The embodiments described above are merely representative examples, and various modifications and alterations are possible for each embodiment when implementing the present invention. [Explanation of symbols]

[0038] L2L, L2R A pair of objective lenses 3 Objective 10. Main Unit 12 Object base member 13 Focus control dial 14 Lead screw 16 Drive nut 17 Focus Plate 17a Guided groove portion 20 Guide member

Claims

1. 1. An optical instrument having a pair of lenses spaced apart from each other in a first direction and movable in a second direction perpendicular to the first direction, A base member; a first screw member rotatable at a fixed position in the second direction; a rotation operation member that is rotated by a user to rotate the first screw member; a second screw member that is screwed into the first screw member and moves in the second direction relative to the base member when the first screw member rotates; a moving member that holds the pair of lenses and moves in the second direction together with the second screw member, a guide portion including a guide groove portion provided on the movable member and a guide member provided on the base member and engaging with the guide groove portion, the guide portion guiding the movement of the movable member in the second direction relative to the base member; the guide portion is disposed on a second plane including a central axis of the first screw member and perpendicular to a first plane including the optical axes of the pair of lenses, and between the central axis of the first screw member and the first plane, a holding portion that guides the movement of the movable member in the second direction and holds the movable member on the base member is provided at a position away from the guide portion in the first direction; the holding portion is disposed on the rotation operation member side with respect to the guide portion in the second direction, An optical device, characterized in that, when viewed from a direction perpendicular to the first plane, at least a portion of the guide portion is disposed in an area that overlaps with the pair of lenses in the second direction.

2. 2. The optical device according to claim 1, wherein a thread pitch of the first screw member and a thread pitch of the second screw member are different from each other to guide the movement of the moving member in the second direction.

3. 3. The optical device according to claim 1, wherein the guide portion is provided at one location on the object side of the first screw member in the second direction.

4. 4. The optical device according to claim 1, wherein the first screw member is made of a metal, and the second screw member is made of a resin.

5. an elastic member that generates a biasing force that presses the moving member against the base member; 5. The optical device according to claim 1, wherein the elastic member is held by the holding portion.

6. the first threaded member is a male thread, 6. The optical device according to claim 1, wherein the second screw member is an internal screw.

7. 3. The optical device according to claim 2, wherein a slanted surface of the thread of the first screw member and a slanted surface of the thread of the second screw member are in pressure contact with each other.

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