JP2005338869A - Method for positioning and fixing two or more lenses in lens barrel and optical equipment applying the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for positioning a lens by which positional relation between the lenses optically or physically facing each other is decided by superposing a plurality of lenses in an optical axis direction while making them abut on each other, and to provide optical equipment applying the method. <P>SOLUTION: A lens barrel 4, a 1st lens 1 being at least two or more lenses housed in the lens barrel and having a conical surface 1b with an optical axis 10 as center at the rib inner wall part of the edge outer periphery part, and a 2nd lens 2 having a conical surface 2a engaged with the conical surface 1b with the optical axis 10 as center at the rib outer wall part of the edge outer periphery part are prepared. The 1st lens 1 is inserted in the lens barrel and positioned in the optical axis direction by abutting on a receiving surface 4a in the lens barrel, and the 2nd lens 2 is inserted in the lens barrel 4 and positioned in the optical axis direction with respect to the optical axis by making the conical surface 1b of the 1st lens 1 abut on the conical surface 2a of the 2nd lens 2. Then, the 2nd lens 2 is fixed in the lens barrel 4, for example, with an adhesive 5 in the vicinity of the insertion part of the lens barrel 4. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a lens positioning method capable of determining a positional relationship between optically or physically facing lenses by overlapping a plurality of lenses in contact with each other in the optical axis direction, and the positioning More specifically, the optical apparatus to which the method is applied, and at least two or more lenses are brought into contact with each other in the optical axis direction through a common conical surface, and the optical axis between the two or more lenses and the optical axis direction And an optical apparatus in which these two or more lenses are positioned and held in an optical system barrel.

  When positioning a plurality of lenses in the lens barrel, conventionally, the distance in the optical axis direction of each lens is provided in the vicinity of the lens edge, for example, by bringing the plurality of lenses into contact with each other in the optical axis direction at the periphery. The position of the optical axis in each lens is determined by contact with a flat surface or contact with a marginal contact. In this case, it is determined by the inner diameter of the lens barrel that is in contact with the inner surface of the lens barrel, or the optical axis adjusted between the lenses in advance is pasted together and placed in the lens barrel. The distance in the optical axis direction is aligned.

  FIG. 4 is a cross-sectional view of a main part of a conventional optical lens barrel in which mutual lenses are bonded in advance and placed in the lens barrel. In the figure, reference numerals 1 and 2 denote lenses bonded in advance. The lens 1 has edge surfaces 1a and 1c perpendicular to the optical axis 10 and a surface 1b parallel to the optical axis 10 on the outer periphery. The lens 2 has an edge surface 2a perpendicular to the optical axis. Reference numeral 4 denotes a part of a lens barrel that holds the lens 1 and has a receiving surface 4 a of the lens 1. Before the lenses 1 and 2 are inserted into the lens barrel 4, the positions of the lenses are adjusted in advance, and the edge surface 1c of the lens 1 and the edge surface 2a of the lens 2 are bonded to each other with an adhesive. The contact surface 1 a of the lens 1 to which the lens 2 is bonded is in contact with the receiving surface 4 a in the optical axis direction of the lens barrel 4, and the outer peripheral surface 1 b of the lens 1 is fitted to the inner diameter 4 b of the lens barrel 4. .

  FIG. 5 is a cross-sectional view of a main part of a conventional optical barrel having a marginal contact structure, in which 1 and 2 are glass lenses, and 4 is a part of a barrel holding the lenses 1 and 2. It is. The lenses 1 and 2 have surfaces 1a and 2a parallel to the optical axis 10 on the outer peripheral portion, respectively, and the lens barrel 4 also has surfaces 4a and 4b parallel to the optical axis 10 by fitting these portions. The center of the lens 1 and the lens 2 is configured to coincide with the optical axis 10. Further, the lens 1 has a wide-angle marginal contact portion 1b smaller than 180 degrees, and this portion abuts on the curved surface portion of the lens 2, and the distance between the lens 1 and the lens 2 is determined.

  FIG. 6 is a cross-sectional view of the main part of the optical system barrel that determines the positional relationship between the lenses using a barrel. In the figure, 1 and 2 are lenses, and the lens 1 is a cover surface perpendicular to the optical axis 10. The lens 2 also has a surface 1b parallel to the optical axis, and the lens 2 also has an edge surface 2a perpendicular to the optical axis 10, and has a surface 2b parallel to the optical axis on the outer periphery. Reference numeral 4 denotes a part of a lens barrel that holds the lenses 1 and 2, and includes a receiving surface 4 a of the lens 1 and a receiving surface 4 c of the lens 2. The lens 1 is engaged with the outer peripheral surface 1b and the inner peripheral surface 4b of the lens barrel 4, and the lens 2 is engaged with the outer peripheral surface 2b and the inner peripheral surface 4d of the lens barrel 4, respectively. The center is configured to coincide with the optical axis 10. When the lenses 1 and 2 are incorporated in the lens barrel 4, the edge surface 1 a of the lens 1 and the receiving surface 4 a of the lens barrel 4 are in contact with each other, and the edge surface 2 a of the lens 2 and the receiving surface of the lens barrel 4 are in contact. 4c is in contact, and this determines the positional relationship between the lenses 1 and 2.

  In the optical system barrel shown in FIG. 4, when lenses of different materials are bonded together, the linear expansion coefficient is different, and therefore the lens may be broken or the lens curved surface may be distorted when the environmental temperature changes.

  In the optical system lens barrel shown in FIG. 5, it is necessary to maintain the accuracy of the marginal contact portion and the outer periphery of each lens and the accuracy of the inner diameter of the lens barrel. In addition, when the lens is held in contact with a marginal contact or the like, stress tends to concentrate on the marginal contact portion, so the lens formed of a relatively low rigidity material such as plastic in the optical system of the marginal contact structure. However, there is a problem that the lens surface is distorted and the optical performance deteriorates even if the accuracy of the outer periphery of each lens and the accuracy of the inner diameter of the lens barrel are maintained. It was necessary to form.

  Further, in the optical system lens barrel shown in FIG. 6, since the outer diameter of the lens and the inner diameter of the lens barrel are engaged to perform positioning in the direction perpendicular to the optical axis, the accuracy of the outer periphery of each lens is also increased. It is necessary to keep the precision of the edge thickness and the precision of the inner diameter of the lens barrel. In order to determine the positional relationship of the lenses that align the optical axes of a plurality of lenses and face each other, a mirror is used at each lens positioning part. It is necessary to maintain accuracy in the component parts composed of two types of the inner diameter accuracy of the cylinder and the outer diameter accuracy of the lens.

  The present invention has been made in view of the above-described circumstances, and determines the positional relationship of a plurality of lenses overlapping in the optical axis direction of the next stage if at least one lens position is determined in a lens barrel. And an optical apparatus using the method.

  The invention according to claim 1 is a first lens having a lens barrel and two or more lenses housed in the lens barrel, and having a conical surface centered on the optical axis at the rib inner wall portion of the outer periphery of the edge. And a second lens having a conical surface that engages with the conical surface with the optical axis as a center at a rib outer wall portion of the outer peripheral portion of the edge, and the first lens is inserted into the lens barrel and the mirror Abutting on the receiving surface in the tube and positioning in the optical axis direction, and then inserting the second lens into the lens barrel and connecting the conical surface of the first lens and the conical surface of the second lens The surface is brought into contact with the optical axis and positioned in the optical axis direction, and then the second lens is fixed to the barrel.

  The invention of claim 2 comprises a lens barrel and two or more lenses inserted and arranged in the lens barrel, and the first lens is a conical surface centered on the optical axis on the rib inner wall of the outer periphery of the edge. And the second lens has a conical surface centered on the optical axis and engaged with the conical surface on the rib outer wall portion of the outer periphery of the edge, and the conical surface of the first lens and the second lens The conical surface comes into surface contact and is housed in the lens barrel, and the second lens is fixed to the lens barrel.

  The invention of claim 3 is the invention of claim 2, further comprising a third lens having a conical surface centered on the optical axis at the rib outer wall portion of the outer periphery of the edge, and the second lens is the conical surface. The rib inner wall portion of the outer peripheral portion has a second conical surface that engages with the conical surface of the third lens on the side opposite to the side where the third conical surface is provided, and the second conical surface is the third conical surface. The third lens is fixed to the lens barrel in place of the second lens, while being in surface contact with the conical surface of the lens and housed in the lens barrel.

  According to a fourth aspect of the invention, in the second or third aspect of the invention, the first lens abuts on the receiving surface of the barrel only in the optical axis direction and has a clearance in the radial direction. It is.

  According to a fifth aspect of the present invention, in the invention according to any one of the second to fourth aspects, the conical surface is provided in a part, a plurality of locations, or the entire circumference of the edge of the lens in the circumferential direction. It is a feature.

  The invention of claim 6 is characterized in that, in the invention of any one of claims 2 to 5, the second lens or the third lens is fixed to the inner wall of the lens barrel with an adhesive. is there.

  According to the lens positioning method of the present invention, a lens having a conical surface centered on the optical axis is brought into contact with the receiving surface in the lens barrel on the rib inner wall portion of the outer periphery of the edge, and then the interior of the lens barrel is By inserting the next stage lens having a conical surface centered on the optical axis into the rib outer wall of the outer edge of the edge, the positional relationship between the optical axis between the lenses and the distance in the optical axis direction can be determined simultaneously. Position adjustment between the lenses and accuracy of the inner diameter of the lens barrel can be eliminated, and deterioration of the optical performance of the lens can be prevented even in a fixing method using an adhesive or the like.

  In the optical apparatus to which the optical system positioning method of the present invention is applied, the first lens is positioned inside the lens barrel in contact with the receiving surface of the lens barrel, and the next lens is the first lens. Are positioned inside the lens barrel in contact with the conical slope of the outer peripheral portion of the edge in the optical axis direction, and are fixedly bonded to the lens barrel by an adhesive at the insertion site of the lens barrel. These lenses can be easily incorporated into a lens barrel that holds these lenses, and these lenses are positioned and fixed with high reliability without causing deterioration of optical performance.

  The present invention relates to a method for positioning and fixing two or more lenses in a lens barrel, more specifically, a positioning method between lenses in an optical system barrel, and an optical system barrel to which the positioning method is applied. A lens positioning method in an optical system barrel having at least two or more lenses in contact with each other in the optical axis direction, wherein the lens is inserted into the barrel, and the lens is placed in the barrel The lens is placed in contact with the receiving surface and positioned in the optical axis direction, and the lens in the next stage is contacted with this lens to position the optical axis of the lens facing each other and the distance in the optical axis direction. The positions of the lenses are held by being fixed by an adhesive or welding in the vicinity, or by pressing the outer peripheral part of the edge of the last stage lens with an elastic body in the optical axis direction.

  FIG. 3 is a view for explaining the rib surface on the outer periphery of the edge to which the present invention is applied. In the figure, 10 is an optical axis, 11 is a cone centered on the optical axis 10, and 12 is a surface of the cone 10. In the present invention, the two lenses are brought into contact with each other via a part 12 of the surface of the cone 10 to simultaneously adjust the optical axes of two or more lenses and the distance in the optical axis direction. It is what I did.

  FIG. 1 is a cross-sectional view of a principal part for explaining the first embodiment of the present invention. In the figure, reference numerals 1 and 2 denote lenses made of synthetic resin, and reference numeral 4 denotes a lens barrel for holding the lenses 1 and 2. The lens 1 has a surface 1b of a cone 11 centered on the optical axis 10 on the rib inner wall of the outer periphery of the edge, and the lens 2 is the same as the lens 1 centered on the optical axis 10 of the rib outer wall of the outer periphery of the edge. A surface 2 a of the cone 11 is provided, and the surfaces 1 b and 2 a that are the cones of each other are in surface contact with each other and are contained in the lens barrel 4. Reference numeral 5 denotes an adhesive for fixing the lens 2 and the lens barrel 4. As shown in FIG. 1, the lens 1 and the lens barrel 4 have a surface 1a of the lens 1 and a receiving surface 4a of the lens barrel 4 only in the optical axis 10 direction. It abuts and has a slight clearance in the direction perpendicular to the optical axis 10 (radial direction).

  As the lens positioning and holding method in the above embodiment, first, the lens 1 is inserted into the lens barrel 4 from the right side of the lens barrel 4, and then the next stage lens 2 is similarly inserted into the lens barrel 4 from the right side of the lens barrel 4. Insert into. At this time, if the lenses 1 and 2 are fitted or pressed into the lens barrel 4 at the outer periphery thereof, the lenses 1 and 2 are likely to be deformed. Therefore, the outer diameter of the lenses 1 and 2 is the inner diameter of the lens barrel 4. It is set smaller. For this reason, when the lenses 1 and 2 are inserted into the lens barrel 4 in that order and a load is applied to the edge of the edge of the lens 2 from the right in the figure, the receiving surface 1b of the lens 1 is restricted to the receiving surface 2a of the lens 2. Then, the lens 1 moves in a direction perpendicular to the optical axis 10 and the centers of the lenses 1 and 2 are aligned with the optical axis 10. Then, the state shown in FIG. 1 is obtained by injecting the adhesive 5 into the insertion portion of the lens barrel 4 and fixing the outer periphery of the lens 2 and the lens barrel 4.

  According to the lens positioning and holding as described above, the lens 1 is not directly fixed to the lens barrel 4 by the adhesive 5 or the like, but is sandwiched between the conical slope 2a of the edge portion of the lens 2 and the receiving surface 4a of the lens barrel 4. Therefore, the position does not shift. In addition, since the lens 1 is not bonded and the bonded portion of the lens 2 is provided at a portion away from the lens portion at the surface distance, the lens 2 can be prevented from being deformed due to the shrinkage of the adhesive 5. There is. Therefore, the lens 2 is pulled by the shrinkage at the time of curing of the adhesive 5, and the optical performance is not deteriorated by shifting its position. The lens barrel 4 has a receiving surface 4 a that is a surface 1 a perpendicular to the optical axis 10 of the lens 1, and the receiving surface 4 a is formed on a surface that is perpendicular to the optical axis 10.

  According to the positioning method between the lenses as described above, the lenses can be connected to each other only by inserting the first-stage lens and the next-stage lens into the lens barrel in that order without engaging the lens barrel. It is possible to determine the optical axis and distance of the lens, and it is not necessary to stick each other's lens directly or to maintain the inner diameter accuracy of the lens barrel side, and it is possible to position the optical axis and the positional relationship between the lenses simultaneously with high accuracy. An effect is obtained.

FIG. 2 is a cross-sectional view of a main part for explaining a second embodiment of the present invention, in which 1, 2, 3 are lenses made of synthetic resin, and 4 is a lens barrel holding the lenses 1, 2, 3. It is. Lens 1 has a conical 11 ₁ surface 1b around the optical axis 10 to the rib inner wall of the flange outer peripheral portion, the lens 2, the optical axis 10 as the center to the rib outer wall of the flange outer peripheral portion, the lens 1 It has the same cone 11 _first surface 2a and, and on the opposite side of said surface 2a, has a conical 11 ₂ face 2b around the optical axis 10 to the rib inner wall of the flange outer peripheral portion, the lens 3 Like the lens 2, the rib inner wall portion of the outer peripheral portion has a surface 3 a of the cone 11 ₂ centered on the optical axis 10 and the inner peripheral portion has a surface 3 b of the cone 11 ₃ centered on the optical axis 10. Have. The lenses 1, 2, and 3 are accommodated in the lens barrel 4 so that the surfaces that form the cones of the edges contact each other.

  In FIG. 2, the lens 1 and the lens barrel 4 are in contact with the surface 1 a of the lens 1 and the receiving surface 4 a of the lens barrel 4 only in the direction of the optical axis 10, and have a slight clearance in the direction perpendicular to the optical axis 10. . As a lens positioning and holding method in the present embodiment, first, the lens 1 is inserted into the lens barrel 4 from the right side of the lens barrel 4, and then the next stage lenses 2 and 3 are respectively inserted from the right side of the lens barrel 4. It inserts in the lens-barrel 4 in order. At this time, if the lenses 1, 2, 3 are fitted or pressed into the lens barrel 4 at the outer periphery, the lenses 1, 2, 3 are likely to be deformed. Is set smaller than the inner diameter of the lens barrel 4. For this reason, when the lens barrel 4 is fixed and a load is applied to the outer peripheral portion of the edge of the lens 3 from the right side, the lenses 1 and 2 are regulated by the receiving surface 4a of the lens barrel 4 and the edge inclined surface 3a of the lens 3. , 3 coincide with the optical axis 10. Then, the state shown in FIG. 2 is obtained by injecting the adhesive 5 into the insertion portion of the lens barrel 4 and fixing the outer peripheral portion of the lens 3 and the lens barrel 4.

  According to the lens positioning and holding configuration as described above, the lenses 1 and 2 are not directly fixed to the lens barrel 4 by the adhesive 5 or the like, but the conical slope 3a at the edge of the lens 3 and the receiving surface 4a of the lens barrel 4. The position is not shifted because it is sandwiched between the two. The lenses 1 and 2 are not bonded, and the bonding portion of the lens 3 is provided at a portion away from the lens portion in terms of the surface distance, so that the lens 3 can be prevented from being deformed by the shrinkage of the adhesive 5. effective. Therefore, the lens 3 is pulled by the shrinkage when the adhesive 5 is cured, and the position thereof is not shifted and the optical performance is not deteriorated. As shown in FIG. 2, the lens barrel 4 has a receiving surface 4 a of a surface 1 a perpendicular to the optical axis 10 of the lens 1, and the receiving surface 4 a is formed on a surface perpendicular to the optical axis 10. . In this way, by providing a conical inclined surface with the optical axis as the center on the inner and outer peripheral portions of the ribs of the lens edge, a plurality of lenses can be contacted in multiple stages, and the optical axis and the positional relationship between the lenses can be determined simultaneously.

  According to the lens positioning in the optical system barrel shown in each of the above-described embodiments, a plurality of lenses can be easily incorporated into the barrel, and the last stage of the incorporated lenses is attached to the barrel. Even if it is fixed by, etc., it can be positioned and fixed with high reliability without causing deterioration of optical performance. In addition, the positioning of such a configuration can be used for an optical apparatus such as a photographic camera or an optical measuring instrument.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made in actual product development, and the number of lenses incorporated in the lens barrel. Can be further increased.

It is principal part sectional drawing for demonstrating Example 1 of the lens-barrel to which this invention was applied. It is principal part sectional drawing for demonstrating Example 2 of the lens-barrel to which this invention was applied. It is a figure for demonstrating the conical surface (rib surface) used for the lens positioning method by this invention. It is principal part sectional drawing of the conventional optical system lens barrel which mutually affixed the lens in advance and made it fit in a lens barrel. It is principal part sectional drawing of the conventional optical system barrel which has a marginal contact structure. It is principal part sectional drawing of the optical system barrel which determines the positional relationship of a mutual lens using a barrel.

Explanation of symbols

1, 2, 3 Lens 4 Lens barrel 5 Adhesive 10 Optical axis 11, 11 ₁ , 11 ₂ , 11 ₃ Conical surface

Claims (6)

  A lens barrel, two or more lenses housed in the lens barrel, the first lens having a conical surface centered on the optical axis at the rib inner wall portion of the outer periphery of the edge, and the rib of the outer periphery of the edge A second lens having a conical surface that engages with the conical surface about the optical axis is prepared on the outer wall, and the first lens is inserted into the lens barrel so as to contact the receiving surface in the lens barrel. Then, the second lens is inserted into the lens barrel, and the conical surface of the first lens and the conical surface of the second lens are brought into surface contact with each other. And positioning the two or more lenses in the lens barrel, wherein the second lens is fixed to the lens barrel.   The lens comprises a lens barrel and two or more lenses inserted and disposed in the lens barrel. The first lens has a conical surface centered on the optical axis on the rib inner wall of the outer periphery of the edge. The lens has a conical surface centered on the optical axis and engaged with the conical surface on the rib outer wall portion of the outer periphery of the edge, and the conical surface of the first lens and the conical surface of the second lens are in surface contact with each other. An optical apparatus housed in the lens barrel, wherein the second lens is fixed to the lens barrel.   3. The optical apparatus according to claim 2, further comprising a third lens having a conical surface centered on the optical axis at a rib outer wall portion of the outer peripheral portion of the edge, wherein the second lens is provided with the conical surface. A rib conical surface engaging with the conical surface of the third lens on the rib inner wall portion of the outer periphery of the edge on the side opposite to the side where the conical surface is located, and the second conical surface is a conical surface of the third lens And an optical device in which the third lens is fixed to the lens barrel in place of the second lens.   4. The optical apparatus according to claim 2, wherein the first lens contacts the receiving surface of the barrel only in the optical axis direction and has a clearance in the radial direction.   5. The optical apparatus according to claim 2, wherein the conical surface is provided in a part, a plurality of locations, or the entire circumference of the lens in a circumferential direction of the lens. 6. The optical apparatus according to claim 2, wherein the second lens or the third lens is fixed to an inner wall of the barrel with an adhesive.

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