WO2007132833A1

WO2007132833A1 - Composite lens and method of producing the same

Info

Publication number: WO2007132833A1
Application number: PCT/JP2007/059923
Authority: WO
Inventors: Toshiaki Takano; Jun Murata
Original assignee: Panasonic Corporation
Priority date: 2006-05-16
Filing date: 2007-05-15
Publication date: 2007-11-22
Also published as: JPWO2007132833A1

Abstract

A composite lens and a method of producing such a lens, or more particularly, a composite lens where a second lens section is joined to a first lens section and a method of producing such a lens. The composite lens has enhanced optical characteristics. The composite lens (10) has the first lens section (11) having a lens surface (12) and also has the second lens section connected at the lens surface (12) to the first lens section (11) and having a lens surface (15) on the opposite side of the joint surface (16). The first and second lens surfaces (12, 15) have first and second positioning sections (12a, 15a), respectively. Further, the first positioning section (12a) is located at least on a straight line that is substantially in parallel with the optical axis and passes through the second positioning section (15a). Alternatively, the second positioning section (15a) is located at least on a straight line that is substantially in parallel with the optical axis and passes through the first positioning section (12a).

Description

Specification

Compound lens and manufacturing method thereof

Technical field

The present invention relates to a compound lens and a method for manufacturing the same, and to a compound lens in which a second lens unit is joined to a first lens unit and a method for manufacturing the same.

Background art

Conventionally, a composite optical element in which two or more optical parts are joined to each other is known. Some composite optical elements are disclosed in Patent Document 1! In some cases, a diffractive surface is formed on the joint surface or the surface of the composite optical element, and the composite optical element having such a diffractive surface is molded using the methods disclosed in Patent Documents 2 and 3. The

Patent Document 1: Japanese Patent Laid-Open No. 11-337818

Patent Document 2: JP 2004-126392 A

Patent Document 3: Japanese Patent Application Laid-Open No. 2004-240417

Disclosure of the invention

Problems to be solved by the invention

[0003] By the way, in the compound lens in which the second lens unit is bonded to the lens surface of the first lens unit, the second lens unit is bonded to the first lens unit so that the optical axes coincide with each other! Otherwise, there is a risk of deteriorating the optical characteristics of the compound lens.

[0004] The present invention has been made in view of efforts, and an object of the present invention is to provide a composite lens capable of improving optical characteristics and a method for manufacturing the same. Means for solving the problem

Each of the first, second, and third compound lenses of the present invention includes a first lens unit having a first lens surface, and a second lens unit joined to the first lens unit on the first lens surface. It is equipped with.

[0006] In the first compound lens, a first positioning portion exists on the first lens surface. The second lens unit has a second lens surface opposite to the first cemented surface where the second lens unit is cemented to the first lens unit, and the second lens surface includes a second lens surface. A positioning part exists. The first positioning portion is present at least on a straight line that is substantially parallel to the optical axis and passes through the second positioning portion.

[0007] That is, in the first compound lens, the first position on the straight line passing through the second positioning portion does not have to be completely overlapped with the second positioning portion in the optical axis direction. Force for which the determining part exists The second positioning part does not have to exist on a straight line passing through the first positioning part. Specifically, the first positioning part is formed in a ring shape centered on one point on the optical axis of the first lens part, and the second positioning part is centered on one point on the optical axis of the second lens part. And it may exist on a part of the circumference existing on the second lens surface.

[0008] In the second compound lens, a first positioning portion exists on the first lens surface. The second lens unit has a second lens surface opposite to the first cemented surface where the second lens unit is cemented to the first lens unit, and the second lens surface includes a second lens surface. A positioning part exists. The second positioning portion is present at least on a straight line that is substantially parallel to the optical axis and passes through the first positioning portion.

[0009] That is, in the second compound lens, the second position does not have to be completely overlapped with the first positioning portion in the optical axis direction. Force for which the determining part exists The first positioning part does not have to exist on a straight line passing through the second positioning part. Specifically, the second positioning part is formed in a ring shape centered on one point on the optical axis of the second lens part, and the first positioning part is centered on one point on the optical axis of the first lens part. And may exist on a part of the circumference existing on the first lens surface.

In the third compound lens, there are two first and second positioning portions on the first and second lens surfaces, respectively. The first optical unit has a third lens surface on the side opposite to the first lens surface, and the lens is positioned on the optical axis outside the lens with respect to the intersection of the third lens surface and the optical axis. Looking at the inside, one of the two first positioning parts exists on a straight line that faces from the viewpoint to one of the two second positioning parts. The other of the two lies on a straight line that faces from the viewpoint to the other of the two second positioning portions.

[0011] In the method for manufacturing a composite lens of the present invention, a second lens member is bonded to the first lens surface of the first lens member to manufacture a composite lens. Specifically, the first positioning part on the first lens surface Preparing the first lens member formed with (a), preparing the molding die for molding the second lens member (b), and the molten optical material used as the material of the second lens member A step (c) of setting a material on a molding die and pressing a first lens member on the set optical material. In the step (b), a molding die having a molding surface for molding the second lens surface of the second lens member and a molding positioning portion formed on the molding surface is prepared. In step (c), the first positioning portion is overlapped with the molding positioning portion in a direction substantially parallel to the optical axis of the first lens member, the first lens surface is brought into contact with the optical material, 1Press the first lens member onto the optical material in a direction approximately parallel to the optical axis of the lens member.

The invention's effect

According to the present invention, it is possible to improve the optical characteristics of the compound lens.

Brief Description of Drawings

1 is a cross-sectional view of a compound lens according to Embodiment 1, and FIG. 1B is a plan view of the downward force in FIG. is there.

[FIG. 2] FIG. 2 is a flowchart showing a method of molding a compound lens according to Embodiment 2 in (a) to (d).

[FIG. 3] FIG. 3 (a) is a cross-sectional view of the first and second positioning portions in Modification 1 of Embodiment 1, and FIG. 3 (b) shows the downward force in FIG. It is a top view.

[FIG. 4] FIG. 4 (a) is a cross-sectional view of another first and second positioning portion in Modification 1 of Embodiment 1, and FIG. 4 (b) shows the compound lens as well as the downward force in (a). It is a top view at the time.

[FIG. 5] FIG. 5 (a) is a cross-sectional view of still another first and second positioning portions in Modification 1 of Embodiment 1, and (b) is a view of the compound lens from below in (a). It is a plan view when

[FIG. 6] FIG. 6 (a) is a cross-sectional view of still another first and second positioning portions in Modification 1 of Embodiment 1, and (b) is a view of the compound lens from below in (a). It is a plan view when

[FIG. 7] FIG. 7 (a) is a cross-sectional view of still another first and second positioning portions in Modification 1 of Embodiment 1, and (b) is a view of the compound lens from below in (a). It is a plan view when FIG. 8 is a cross-sectional view of a compound lens according to Modification 2 of Embodiment 1.

FIG. 9 is a cross-sectional view of a compound lens according to Modification 3 of Embodiment 1.

FIG. 10 is a cross-sectional view of a compound lens according to Modification 4 of Embodiment 1.

FIG. 11 is a cross-sectional view of a compound lens according to Modification 5 of Embodiment 1.

FIG. 12 (a) is a cross-sectional view of the compound lens according to Embodiment 2, and FIG. 12 (b) is a plan view of the downward force compound lens in (a).

FIG. 13 (a) is a cross-sectional view of a compound lens according to Embodiment 3, and FIG. 13 (b) is a plan view when the downward force in (a) is viewed from the compound lens.

FIG. 14 is a cross-sectional view of a compound lens according to Embodiment 4.

FIG. 15 is a cross-sectional view of a compound lens according to Embodiment 5.

FIG. 16 is a cross-sectional view of a compound lens according to Embodiment 6.

FIG. 17 is a cross-sectional view of a compound lens according to Embodiment 7.

FIG. 18 is a cross-sectional view of a compound lens that is effective in Embodiment 8.

Explanation of symbols

[0014] 4 Wrinkle resin preform (optical material)

10, 20, 30, 40, 50, 60, 70, 80 Compound lens

11, 21, 31, 41, 51, 71 1st lens

12, 22, 32, 42, 52, 72 Lens surface (first lens surface)

12a, 22a, 32a, 42a, 52a, 72a 1st positioning part

13, 23, 33, 43, 53, 73 Lens surface (third lens surface)

14, 24, 34, 44, 54 Second lens

15, 25, 35, 45, 55 Lens surface (second lens surface)

15a, 25a, 35a, 45a, 55a Second positioning part

15b, 25b, 35b, 45b, 55b First uneven surface part (uneven surface part)

73a 3rd positioning part

91 Mold

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is as follows. It is not limited to the embodiment below.

[0016] Embodiment 1

FIG. 1 is a diagram illustrating a configuration of the compound lens 10 according to the first embodiment. FIG. 1 (a) is a schematic sectional view, and FIG. 1 (b) is a plan view of the compound lens 10 when the downward force in FIG. 1 (a) is also seen.

The compound lens 10 according to the present embodiment includes a first lens unit 11 and a second lens unit 14. The first lens unit 11 is an aspheric lens made of glass, and has two lens surfaces, that is, a lens surface (first lens surface) 12 and a lens surface (third lens surface) 13. The second lens unit 14 is made of grease and is bonded to the lens surface 12 of the first lens unit 11. Specifically, the second lens unit 14 is bonded to the lens surface 12 so that the optical axis thereof coincides with the optical axis of the first lens unit 11. As described above, since the optical axis of the first lens unit 11 and the optical axis of the second lens unit 14 coincide with each other, the compound lens 10 according to the present embodiment makes the optical axes coincide with each other. Compared with a compound lens that is joined without any problems, the optical characteristics (aberration, light transmittance, light condensing rate, etc.) of the compound lens can be improved.

[0018] The compound lens 10 that is helpful in the present embodiment is further shown. A first positioning portion 12a exists on the lens surface 12 of the first lens portion 11. The first positioning part 12 a indicates the position of the optical axis of the first lens part 11 on the lens surface 12, and exists on the optical axis of the first lens part 11. The second lens portion 14 has a lens surface (second lens surface) 15 on the side opposite to the first cemented surface 16, and the lens surface 15 has a second positioning portion 15 a. The second positioning portion 15 a indicates the optical axis position of the second lens portion 14 on the lens surface 15, and exists on the optical axis of the second lens portion 14. In the optical axis direction of the compound lens 10, the first positioning portion 12a and the second positioning portion 15a are arranged side by side. Thereby, in the compound lens 10, the second lens unit 14 is joined to the first lens unit 11 so that the optical axis thereof coincides with the optical axis of the first lens unit 11 without deviation.

In the present embodiment, the first and second positioning portions 12a, 15a are each convex in a semicircular cross section, and the most protruding portions are the optical axes of the first and second lens portions 12, 15, respectively. Preferably it is present above. Further, the first and second positioning portions 12a and 15a are formed in sizes and positions that do not affect the optical characteristics, respectively. It is preferable. Specifically, it is preferable that the size of the first positioning portion 12a on the lens surface 12 of the first lens portion 11 is about 100 μm, and the depth of the first positioning portion 12a is about 100 μm. It is preferable. The same applies to the second positioning portion 15a.

Further, in the compound lens 10 according to the present embodiment, an uneven surface portion (hereinafter referred to as “first uneven surface portion”) 15 b having a sawtooth cross section exists on the lens surface 15 of the second lens portion 14. Yes. The first concave convex surface portion 15b is a diffractive portion, and is present outside the second positioning portion 15a, and is present in a ring shape centered on one point on the optical axis of the composite lens 10. That is, on the lens surface 15 of the second lens portion 14, as shown in FIG. 1 (b), the second positioning portion 15a, the smooth smooth surface portion 15c, the first uneven surface portion 15b, and the smooth smooth surface portion 15c They exist in order from the axial center to the periphery, and exist in concentric circles centered on one point on the optical axis of the compound lens 10. As a result, in the compound lens 10 according to the present embodiment, the optical power differs between the first concave / convex surface portion 15b and the smooth surface portion 15c. Therefore, for example, light having a wavelength is incident on the first concave / convex surface portion 15b to be condensed. The light of the wavelength (≠ λ) is incident on the smooth surface 15c and condensed.

twenty one

it can.

[0021] As described above, in the compound lens 10 according to the present embodiment, the optical axis of the first lens unit 11 and the optical axis of the second lens unit 14 are aligned with each other. Unlike bonded composite lenses, it has excellent optical properties. Further, in the compound lens 10 that is effective in the present embodiment, since the optical power is different between the first uneven surface portion 15b and the smooth surface portion 15c, two lights having different wavelengths can be emitted.

[0022] FIGS. 2A to 2D are schematic cross-sectional views showing a molding process of the compound lens 10 that is useful in the present embodiment.

[0023] In the molding method of the composite lens 10 according to the present embodiment, the first lens member is molded through the steps shown in FIGS. 2 (a) and 2 (b), and then the FIGS. 2 (c) and 2 are used. Through the step shown in (d), the second lens member is bonded to the first lens member, and the composite lens 10 is molded. Specific examples are shown below.

First, as shown in FIG. 2 (a), a glass preform 1 and a molding apparatus are prepared. The glass preform 1 preferably has a shape very similar to the shape of the first lens part 11 after molding. The molding apparatus includes an upper die 81 and a lower die 82. The upper die 81 and the lower die 82 are Each has molding surfaces 81a and 83. The molding surface 81a of the upper mold 81 is smoothly formed so as to correspond to the lens surface 13 of the first lens unit 11. The molding surface 83 of the lower mold 82 is formed so as to correspond to the lens surface 12 of the first lens portion 11, and therefore, a concave portion 83a corresponding to the first positioning portion 12a is formed at the center of the surface. Then, the lower mold 82 is set with the molding surface 83 facing up, the glass preform 1 is set on the molding surface 83, and the upper mold 81 is set on the glass preform 1 with the molding surface 81 a facing down.

[0025] Next, the glass preform 1 is heated to near the glass softening temperature and pressed as shown in Fig. 2 (b), and the molding surfaces of the upper mold 81 and the lower mold 82 are respectively made of glass. Transfer to the surface of Preform 1. When pressing, the upper mold 81 may be pressed against the glass preform 1, and the lower mold 82 may be pressed against the glass preform 1, and the upper mold 81 and the lower mold 82 are pressed against the glass preform 1, respectively. Also good. Then, it is cooled. Accordingly, the first lens member that becomes the first lens portion 11 can be molded. In this way, the first lens member is formed using the press molding method V, and unlike the case where the first lens member is formed using a polishing method or a grinding method, the first lens member is formed by a single molding. Even if the lens surface is aspherical or when the first positioning portion is formed on the lens surface, it can be molded relatively easily by processing the mold. .

Next, as shown in FIG. 2 (c), a resin preform (optical material) 4 and a molding apparatus are prepared. The molding apparatus includes a lower mold (molding mold) 91, and the lower mold 91 has a molding surface 92. The molding surface 92 is formed so as to correspond to the lens surface 15 of the second lens portion 14, and therefore, a concave molding positioning portion 92a is provided at the center of the surface so as to correspond to the second positioning portion 15a. A convex concave portion 92b is formed on the outer side of the molding positioning portion 92a so as to correspond to the first concave and convex surface portion 15b, and the outer side of the convex concave portion 92b is formed smoothly. . Then, after setting the lower die 91 with the molding surface 92 facing upward, the molten resin preform 4 is set on the molding surface 92 and the first lens member is set on the resin preform 4. At this time, the first lens member is set on the lower mold 91 so that the molding positioning portion 92a overlaps the first positioning portion 12a in the optical axis direction of the first lens member. Thereby, the compound lens 10 can be molded by aligning the optical axis of the first lens member with the central axis of the molding surface 92. [0027] Then, pressing is performed as shown in Fig. 2 (d). At this time, since the resin is softer than the glass, the shape of the lens surface of the first lens member does not change even if the first lens member is pressed against the resin preform 4. Further, since the second glass preform 4 flows in accordance with the shape of the lens surface 12 and enters the uneven portion 92b of the molding surface 92, the shape of the uneven portion 92b is suitably transferred to the surface of the second glass preform 4. The In this way, the compound lens 10 which is effective in the present embodiment can be molded.

[0028] As described above, in the method of manufacturing the composite lens 10 according to the present embodiment, the first lens member is mounted on the lower mold so that the optical axis of the first lens member coincides with the central axis of the molding surface 92. Therefore, the compound lens 10 can be molded by aligning the optical axis of the first lens member with the optical axis of the second lens member.

[0029] Such a compound lens 10 can be mounted on an optical device such as an imaging device, an illumination device, and an optical disk recording / reproducing device. The imaging device is a device for photographing a subject, for example, a digital still camera or a digital video camera. The illumination device is a device for irradiating light to an object to be illuminated, for example, a projector. Optical disc recording / playback devices record digital versatile discs (hereinafter referred to as DVDs), compact discs (hereinafter referred to as CDs), Blu-ray discs (registered trademarks, hereinafter referred to as BDs (registered trademarks)), and the like. It is a device for playback. In general, DVD, CD, and BD (registered trademark) have different light source wavelengths for recording and playback, optical disc thickness, and the like. It is necessary to devise an optical system in order to be able to record / reproduce images. By using the compound lens 10 that is effective in this embodiment, an optical disk recording / reproducing apparatus compatible with multiple types of information recording media is realized. can do.

[0030] It should be noted that the shapes of the first and second positioning portions are not limited to the above description, and may be the shapes shown in a first modification described later. Further, the shape of the compound lens and the shape of the first uneven surface portion are not limited to the above description, and may be shapes shown in second to fourth modifications described later.

[0031] (First modification)

In the first modification, other shapes of the first and second positioning portions are shown. Figures 3 through 7 Both are diagrams showing other shapes of the second positioning portion. In any of the drawings, (a) is a view showing a cross section of the second positioning portion, and (b) is a plan view of the lens surface force of the second lens portion as viewed from the second positioning portion. In FIGS. 3 to 7, the description of the first positioning portion is omitted in order to avoid complication of the drawings. Therefore, the description of the first positioning portion is also omitted in the following.

[0032] As a modification when the second positioning portion is formed in a convex shape, as shown in FIGS. 3 (a) and (b), the second positioning portion 115a may be formed in a triangular cross section. As shown in FIGS. 4 (a) and 4 (b), the second positioning portion 125a may be a cross formed on the lens surface 125. At this time, it is preferable that the intersection of the cross exists on the optical axis of the second lens portion 124.

[0033] Further, the second positioning portion may be formed in a concave shape. For example, in FIGS. 5 (a) and 5 (b), the second positioning portion 135a is formed in a concave shape having a semicircular cross section. 6 (a) and 6 (b), the second positioning portion 145a is formed in a concave shape having a triangular cross section.

Further, in FIGS. 7 (a) and (b), the second positioning portion 155a is a convex cross formed on the lens surface 154, but the second positioning portion 155a shown in FIGS. 4 (a) and (b) 2 Unlike the positioning part 125a, the cross shafts have different lengths. Thus, if the second positioning portion 155a is asymmetric with respect to the optical axis of the second lens portion 154, the second positioning portion 155a indicates the xy direction in the second lens surface 155 of the second lens portion 154, As a result, the second lens member can be joined to the first lens member by matching the xy directions in the lens surface.

[0035] (Second modification)

FIG. 8 is a schematic cross-sectional view of a compound lens 210 that works on the second modification of the first embodiment. In the compound lens 210 that is effective in the present modification, the first lens portion 211 has a flat plate shape, and the first uneven surface portion 215b of the second lens portion 214 has a plurality of uneven portions having a stepped cross section. The first concavo-convex surface portion 215b is a diffractive portion formed on the lens surface 215 opposite to the first joint surface 216, as in the first embodiment.

[0036] Further, the first and second positioning portions 212a and 215a described in the first embodiment are formed in the compound lens 210 according to this modification. That is, the first positioning portion 212a is formed on the lens surface 212 of the first lens portion 211, and is on the optical axis of the first lens portion 211. Existing. Further, the second positioning portion 215a is formed on the lens surface 215 of the second lens portion 214, and exists on the optical axis of the second lens portion 214. The first positioning unit 212a and the second positioning unit 215a are arranged side by side in the optical axis direction.

[0037] (Third Modification)

FIG. 9 is a schematic cross-sectional view of a compound lens 220 that works on the third modification of the first embodiment. The compound lens 220 that is effective in this modified example has a structure that is very similar to the compound lens 210 described in the second modified example. The first uneven surface portion 225b of the second lens portion 224 is a lens array portion. . Specifically, a plurality of concave lenses are arranged on the first uneven surface portion 225b. The first uneven surface portion 225b is formed on the lens surface 225 of the second lens portion 224 as in the first embodiment, and the lens surface 225 exists on the opposite side of the first joint surface 226. Further, the first and second positioning forces 222a and 225a described in the first embodiment are formed on the compound lens 220.

[0038] (Fourth modification)

FIG. 10 is a schematic cross-sectional view of a compound lens 230 that works on the fourth modification of the first embodiment. The compound lens 230 that is useful in this modification has a configuration similar to that of the compound lens 10 described in the first embodiment, but the first uneven surface portion 235a of the second lens portion 234 is a phase step portion. Specifically, a plurality of phase step surfaces having a stepped cross section are formed on the first uneven surface portion 235a. The first uneven surface portion 235a is formed on the lens surface 235 of the second lens portion 234 as in the first embodiment, and the lens surface 235 exists on the opposite side of the first joint surface 236. Further, the composite lens 230 is formed with the first and second positioning portions 12a and 235a described in the first embodiment.

[0039] (Fifth Modification)

FIG. 11 is a schematic cross-sectional view of a compound lens 240 that works on the fifth modification of the first embodiment. The compound lens 240 that works well with the present modification has a configuration similar to that of the compound lens 10 described in the first embodiment, but the first uneven surface portion 245a of the second lens portion 244 is an antireflection portion. Specifically, a plurality of cone-shaped projections are formed on the first uneven surface portion 245a, and the cone-shaped projections are arranged at a pitch equal to or less than the wavelength of the light to be reflected. The first uneven surface portion 245a is the lens surface of the second lens portion 244 as in the first embodiment. The lens surface 245 exists on the opposite side of the first joint surface 246. Further, the first and second positioning l2a and 245a forces described in the first embodiment are formed on the compound lens 240.

<< Embodiment 2 of the Invention >>

FIG. 12 is a diagram illustrating a configuration of the compound lens 20 according to the second embodiment. FIG. 12 (a) is a schematic sectional view thereof, and FIG. 12 (b) is a plan view of the compound lens 20 as viewed from below in FIG. 12 (a).

[0041] In the complex lens according to the present embodiment, the positions and shapes of the first and second positioning portions 22a and 25a are different from those of the complex lens 10 of the first embodiment. Specifically, as shown in FIG. 12 (b), the first positioning portion 22a exists on the first lens surface 22, and is a ring centered on one point on the optical axis of the first lens portion 21. It is formed in a shape. The second positioning portion 25a is the second lens surface 25 and is present outside the first uneven surface portion 25b, and is formed in a ring shape centered on one point on the optical axis of the second lens portion 24. ing. This ring diameter is substantially the same as the ring diameter of the first positioning portion 22a. Therefore, when the inside of the lens is viewed from the lens surface 25 of the second lens unit 24, the first positioning unit 25a overlaps the second positioning unit 22a in the optical axis direction of the compound lens. Even with such a compound lens 20, when the second lens member is joined to the first lens member, the optical axes can be joined together.

[Embodiment 3 of the Invention]

FIG. 13 is a diagram illustrating a configuration of the compound lens 30 according to the third embodiment. FIG. 13 (a) is a schematic sectional view thereof, and FIG. 13 (b) is a plan view of the compound lens 30 as viewed from below in FIG. 13 (a).

[0043] In the composite lens 30 that is useful in the present embodiment, the positions and shapes of the first and second positioning portions 32a and 35a are different from those of the composite lens 10 in the first embodiment. Specifically, as shown in FIG. 13 (b), four first and second positioning portions 32a and 35a are provided. The four first positioning portions 32a, 32a,... Are provided on the circumference of the first circle around one point on the optical axis, and are arranged at equal intervals on the circumference of the first circle. ing. The same four second positioning parts 35a, 35a, ... are provided outside the first uneven surface part 35b. Are arranged so as to overlap the first positioning portions 32a, 32a,... In the optical axis direction of the compound lens 30 when viewed from the lens surface 35 of the second lens portion 34, respectively. Even in such a compound lens 30, the second lens member can be joined to the first lens member, and the optical axes can be joined to each other.

Note that the number of the first and second positioning portions is not limited to the above description in the present embodiment. In addition, the first and second positioning portions are either provided in the shape of a ring and V, while the remaining one is provided in a scattered manner on the circumference! / ,.

[0045] Also, when the first and second positioning portions are provided on the circumference of the lens, if they are arranged asymmetrically with respect to the optical axis of the composite lens, the xy direction in the lens surface Since the second lens member can be bonded to the first lens member by matching the two, it is preferable.

[Embodiment 4 of the Invention]

FIG. 14 is a schematic sectional view of the compound lens 40 according to the fourth embodiment.

[0047] In the composite lens 40 that is effective in the present embodiment, the relative positional relationship between the first positioning portion 42a and the second positioning portion 45a is different from that of the composite lens 10 in the first embodiment. Specifically, in the compound lens 40 that works according to the present embodiment, there are two first and second positioning portions 42a and 45a, respectively. The two first positioning portions 42a and 42a are present on the circumference of the first circle centered on one point on the optical axis of the first lens portion 41. The two second positioning portions 45a and 45a exist on the circumference of the second circle centered on one point on the optical axis of the second lens portion 44, and the diameter of the second circle is the diameter of the first circle. Bigger than.

[0048] When a viewpoint is placed on the optical axis and outside the compound lens 40 with respect to the intersection with the lens surface 43, and the inside of the compound lens 40 is viewed (from above in FIG. 14, the viewpoint is seen on the optical axis. 1) the first positioning part 42a exists on a straight line passing through the viewpoint and one of the second positioning parts 45a, and the other first positioning part 42a And the second positioning portion 45a on the other side. Even in such a compound lens 40, the second lens member can be joined to the first lens member with the optical axes thereof aligned with each other.

[0049] In the present embodiment, it is sufficient that two or more first and second positioning portions are provided. In addition, the first and second positioning portions are either provided in the shape of a angulation V, while the other one is provided in a dotted manner on the circumference! /. [Embodiment 5 of the Invention]

FIG. 15 is a schematic sectional view of the compound lens 50 according to the fifth embodiment.

In the composite lens 50 according to the present embodiment, an uneven surface portion (hereinafter referred to as “second uneven surface portion”) 52 b is also formed on the lens surface 52 of the first lens portion 51. The second uneven surface portion 52b is present at a position that does not overlap the first uneven surface portion 55b when the compound lens 50 is viewed from the lens surface 55 of the second lens portion. Therefore, when the inside of the compound lens 50 is viewed from the lens surface 55 of the second lens portion 54, the first and second positioning portions 52a and 55a exist at the center of the optical axis. Then, the second uneven surface portion 52b and the first uneven surface portion 55b are arranged in order, and the first uneven surface portion 55b and the second uneven surface portion 52b are concentrically centered on one point on the optical axis of the compound lens 50. ing. Therefore, for example, light having a wavelength is incident around the optical axis to be condensed, and light having a wavelength (≠ λ) is incident on the second uneven surface portion 52b to be condensed.

twenty one

Therefore, the light with the wavelength (≠ λ, λ) can be incident on the first uneven surface portion 55b and collected.

3 1 2

The

[Sixth Embodiment of the Invention]

FIG. 16 is a schematic sectional view of the compound lens 60 according to the sixth embodiment.

In addition to the first and second lens portions 11 and 14 described in the first embodiment, the compound lens 60 that works in the present embodiment includes a third lens portion 61. The third lens unit 61 is made of grease and is joined to the second lens unit 14 at the lens surface 15 of the second lens unit 14 and has a lens surface 62.

[0054] The lens surface 62 exists on the opposite side of the second cemented surface 63 where the third lens unit 61 is cemented to the second lens unit 14, and the third positioning unit 62a and the third uneven surface unit 62b. And have. Similar to the first and second positioning portions 12a and 15a, the third positioning portion 62a indicates the position of the optical axis of the third lens portion 61 on the lens surface 62, and is on the optical axis of the third lens portion 61. Therefore, it is aligned with the first and second positioning portions 12a and 15a in the optical axis direction.

Further, the third uneven surface portion 62b is a diffractive portion, like the first uneven surface portion 15b, and is formed on the periphery of the lens surface 62. When the compound lens 60 is viewed from the lens surface 62 of the third lens unit 61, the first, second, and third positioning units 12a, 15a, 62a are arranged in the optical axis direction at the center of the optical axis. Thus, the first uneven surface portion 15b and the third uneven surface portion 62b are formed in order from the center of the optical axis toward the periphery, and the first uneven surface portion 15b and the third uneven surface portion 62b are a point on the optical axis of the compound lens 60. It is arranged concentrically with the center.

[Embodiment 7 of the Invention]

FIG. 17 is a schematic cross-sectional view illustrating a configuration of a compound lens 70 according to the seventh embodiment.

[0057] The compound lens 70 according to the present embodiment is a lens in which the fourth positioning portion 73a is formed on the compound lens 50 according to the fifth embodiment. Specifically, the fourth positioning portion 73a is formed on the lens surface 73 of the first lens portion 71, and exists on the optical axis of the first lens portion 71 in the same manner as the first positioning portion 72a. Therefore, the first positioning portion 72a, the second positioning portion 45a, and the fourth positioning portion 73a are aligned in the optical axis direction of the compound lens 70.

If the fourth positioning portion 73a is also formed in the first lens portion 71 as described above, the tilt of the composite lens 70 can be controlled when the composite lens 70 is attached to the optical system.

[Embodiment 8 of the Invention]

FIG. 18 is a schematic sectional view of the compound lens 80 according to the eighth embodiment.

The compound lens 80 according to the present embodiment is a lens in which the fourth lens portion 81 is formed on the compound lens 70 of the seventh embodiment. Specifically, the fourth lens portion 81 is made of grease and is joined to the first lens portion 71 at the lens surface 73 of the first lens portion 71, and the lens surface on the opposite side to the third joint surface 83. 82. The lens surface 82 is formed with a fifth positioning portion 82a and a fourth uneven surface portion 82b, and the fourth uneven surface portion 82b is a diffractive portion in the same manner as the first uneven surface portion 45b.

[0061] The fifth positioning portion 82a, like the first positioning portion 72a and the second positioning portion 45a, indicates the position of the optical axis of the fourth lens portion 81 on the lens surface 82. Since it exists on the optical axis, it is aligned with the first positioning portion 72a and the second positioning portion 45a in the optical axis direction. Thus, the fourth lens unit 81 is joined to the lens surface 73 of the first lens unit 71 so that the optical axis thereof coincides with the optical axis of the first lens unit 71 and the optical axis of the second lens unit 44. Yes. Therefore, unlike the compound lens formed by shifting the optical axis and joining the three lens parts, the compound lens 80 that is effective in the present embodiment can prevent the deterioration of the optical characteristics. [Other Embodiments]

Embodiments 1 to 8 may have the following configuration.

[0063] The force that the lens surface of the first lens portion is aspherical may be a flat surface as described in the second and third modifications, or may be a spherical surface, a cylindrical surface, a ball striking surface, and a toric surface. It may be a surface.

[0064] Although the second, third, and fourth lens parts are each made of a resin, specifically, an energy-cured resin is a thermoplastic resin. The energy curable resin is, for example, a thermosetting resin, an ultraviolet curable resin, an electron beam curable resin, or the like, and is a resin that is cured by applying predetermined energy (heat, ultraviolet ray, electron beam, etc.). . For this reason, when molding the second lens part using energy-curing resin, set the molten resin on the uneven surface part of the lower mold and press the first lens part to apply the predetermined energy. Goodbye! For example, when the second lens portion is molded using an ultraviolet curable resin, it may be cured by irradiating with ultraviolet rays. Further, when the second lens part is molded using the thermoplastic resin, the molten resin may be set on the uneven surface part of the lower mold and cooled by pressing the force first lens part.

[0065] The materials of the first, second, third and fourth lens portions are not limited to the above materials. Any of the materials may be glass or resin. In addition, the first, second, third and fourth lens parts may be mixed with impurities without affecting the optical characteristics!

[0066] The force on the surface of the lens that is formed on one lens surface is two or more types on one lens surface.

[0067] In the first embodiment, the first and second positioning portions have substantially the same shape, but may be different from each other. Specifically, the first positioning part may be formed in a semicircular cross section, and the second positioning part may be formed in a triangular cross section. The sizes of the first and second positioning portions may be different from each other. Furthermore, one is formed in a convex shape and the other is formed in a concave shape!

Industrial applicability

[0068] As described above, the present invention can be mounted on an optical disc recording / reproducing apparatus. In addition, it can be mounted on imaging devices (such as digital still cameras and digital video cameras) and display devices (such as projectors).

Claims

The scope of the claims

[1] a first lens portion having a first lens surface;

A first lens surface that is cemented to the first lens portion, and a second lens portion having a second lens surface on the opposite side of the cemented surface;

The first and second lens surfaces have first and second positioning portions, respectively.

The composite lens according to claim 1, wherein the first positioning portion is present at least on a straight line substantially parallel to the optical axis and passing through the second positioning portion.

[2] a first lens portion having a first lens surface;

The compound lens, wherein the second positioning portion is present at least on a straight line substantially parallel to the optical axis and passing through the first positioning portion.

[3] The first positioning portion exists on the optical axis of the first lens portion,

3. The compound lens according to claim 1, wherein the second positioning portion exists on the optical axis of the second lens portion.

[4] The first positioning portion is present at least at a part of the circumference of the first circle existing on the first lens surface around one point on the optical axis of the first lens portion,

The second positioning portion is present on at least a part of the circumference of a second circle existing on the second lens surface centered on one point on the optical axis of the second lens portion, and the second circle 3. The compound lens according to claim 1, wherein a diameter of the lens is substantially the same as a diameter of the first circle.

[5] The first positioning portion is formed in a concave or convex shape on the first lens surface, and the second positioning portion is formed in a concave or convex shape on the second lens surface. The compound lens according to claim 1, wherein:

[6] In the first lens portion, a third positioning portion exists on the third lens surface opposite to the first lens surface, 3. The composite lens according to claim 1, wherein the third positioning portion is present at least on a straight line that is substantially parallel to the optical axis and that passes through the first positioning portion.

[7] An uneven surface portion is present on at least one of the first lens surface other than the first positioning portion and at least one portion of the second lens surface other than the second positioning portion. The compound lens according to claim 1, wherein:

8. The concavo-convex surface portion is at least one of a diffractive portion, a lens array portion having a plurality of convex or concave lens surface forces, a phase step portion, and a light reflection preventing portion. Compound lens.

[9] a first lens portion having a first lens surface;

There are two first and second positioning portions on the first and second lens surfaces, respectively.

When looking at the inside of the lens with the viewpoint on the optical axis outside the lens rather than the intersection of the third lens surface opposite to the first lens surface and the optical axis,

One of the two first positioning portions exists on a straight line that faces from the viewpoint to one of the two second positioning portions,

2. The compound lens according to claim 1, wherein the other of the two first positioning portions is present on a straight line that faces the other of the two second positioning portions from the viewpoint.

[10] A method of manufacturing a compound lens by bonding a second lens member to a first lens surface of a first lens member,

Preparing a first lens member having a first positioning portion formed on the first lens surface (a);

A step (b) of preparing a molding die for molding the second lens member;

A step (c) of setting a molten optical material to be a material of the second lens member on the molding die, and pressing the first lens member on the set optical material;

In the step (b), a molding surface for molding the second lens surface of the second lens member; Preparing a molding die having a molding positioning portion formed on the shape surface;

In the step (C),

After the first positioning portion is overlapped with the molding positioning portion in a direction substantially parallel to the optical axis of the first lens member and the first lens surface is brought into contact with the optical material, the first lens member A method of manufacturing a composite lens, comprising pressing the first lens member onto the optical material in a direction substantially parallel to the optical axis.