JP2010224205A - Joined optical element and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a joined optical element which facilitates positioning of an optical base material and high shape accuracy of an optical surface. <P>SOLUTION: The joined optical element includes: two optical base materials 11 and 12 having contact parts 16<SB>1</SB>and 16<SB>2</SB>on the outside of an optical effective diameter D<SB>0</SB>; a resin layer 2 composed of energy curing resin 1 with which space 5 is filled after forming the space 5 by the two optical base materials 11 and 12 and the contact parts 16<SB>1</SB>and 16<SB>2</SB>; and an air layer 18 with which the outside of the optical effective diameter D<SB>0</SB>between the contact parts 16<SB>1</SB>and 16<SB>2</SB>and the resin layer 2 is filled. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a bonded optical element having a contact portion and a method for manufacturing the same.

  The technique of bonding two or more optical substrates through an energy curable resin is performed, for example, in order to realize optical performance (for example, improvement of chromatic aberration) that is difficult to achieve with only one optical substrate.

  Such a bonded optical element is manufactured by the following method. First, while positioning an uncured energy curable resin between two optical base materials, positioning of the two optical base materials (at least one of a vertical direction and a parallel direction with respect to the optical axis of the base materials) Correct the misalignment). Then, a joining optical element is manufactured by irradiating energy to uncured resin and making it harden | cure.

  However, in general, in order to position the two optical base materials, high accuracy is required for the manufacturing apparatus. For this reason, a method of providing a means for positioning on the optical substrate side has been proposed.

  For example, Patent Document 1 discloses a method in which optical bases are brought into line contact with each other on the outer periphery of the optical effective diameter of two optical bases to be bonded and positioned. Further, Patent Document 2 discloses a technique having a fitting portion that can be positioned by fitting each optical base material outside the optical effective diameter.

JP 2001-42212 A Japanese Patent Laid-Open No. 05-19104

  However, in patent document 1 and patent document 2, since the energy curable resin is sealed, the following problems occur. For example, as shown in FIG. 18, consider a state where two optical base materials 111 and 112 are in contact with each other at a contact portion 116. In this state, it is assumed that the energy curable resin 101 is interposed in the closed space between the two optical base materials 111 and 112 and energy is applied to the energy curable resin 101 to be cured as the resin layer 102. Then, when the resin layer 102 is cured, a volume shrinkage of several percent occurs. Therefore, the two optical base materials 111 and 112 are deformed as indicated by broken lines in the figure due to the volume shrinkage. This is because the optical base materials 111 and 112 are pulled with the shrinkage of the resin energy curable resin 101. As a result, there arises a problem that the surface shapes of the two optical substrates 111 and 112 are deteriorated.

  Further, even when the optical base materials 111 and 112 are not pulled by the shrinkage of the energy curable resin 101, the resin layer 102 is peeled from the bonding surface of the two optical base materials 111 and 112 during the curing of the energy curable resin 101. There also arises a problem that the desired optical performance cannot be obtained due to peeling. This tendency becomes remarkable when the volume of the resin layer 102 is large (in particular, when the thickness of the resin layer 102 in the direction parallel to the optical axis O is large).

  SUMMARY An advantage of some aspects of the invention is that it provides a bonded optical element having high optical base material positioning accuracy and optical surface shape accuracy and a method for manufacturing the same.

In order to achieve the above object, the present invention provides:
At least two optical substrates having contact portions outside the optical effective diameter;
A space is formed by the at least two optical base materials and the contact portion, and a lens layer made of an energy curable resin filled in the space;
And an air layer satisfying the outside of the effective optical diameter between the contact portion and the lens layer.

Further, in the above bonded optical element,
Of the at least two optical substrates, at least one of the opposing contact portions is preferably divided into a plurality of portions outside the effective optical diameter.

Further, in the above bonded optical element,
It is preferable that the air layer is formed in a ring shape.
Further, in the above bonded optical element,
It is preferable to have an air hole which makes the said air layer and external air communicate.

Further, in the above bonded optical element,
The contact portion is preferably formed on a rough surface having fine irregularities.
The present invention
Applying an energy curable resin on the optical surface of the first optical substrate having a contact portion outside the effective optical diameter;
Stretching the energy curable resin with a second optical substrate having a contact portion outside the effective optical diameter;
Contacting the contact part of the first optical substrate with the contact part of the second optical substrate so as to leave an air layer on the outer periphery of the energy curable resin;
And a step of curing the energy curable resin by irradiating energy.

In the above manufacturing method,
In the step of applying the energy curable resin, an amount of the energy curable resin required so that an outer periphery of the energy curable resin when the contact portion is brought into contact is between the optical effective diameter and the contact portion. Is preferably applied.

  According to the present invention, it is possible to provide a bonded optical element with high positioning accuracy of an optical base material and high shape accuracy of an optical surface, and a method for manufacturing the same.

FIG. 3 is a cross-sectional view of two optical substrates in the first embodiment. It is sectional drawing of the joining optical element formed by bonding together two optical base materials. FIG. 6 is a cross-sectional view of two optical substrates in the second embodiment. It is a figure which shows the external appearance of one optical base material. It is sectional drawing of the joining optical element formed by bonding together two optical base materials. FIG. 6 is a cross-sectional view of two optical substrates in the third embodiment. It is sectional drawing of the intermediate joining optical element formed by bonding together two optical base materials. It is sectional drawing of an intermediate joining optical element and an optical base material. It is sectional drawing of the joining optical element formed by bonding an intermediate joining optical element and an optical base material. FIG. 10 is a cross-sectional view of two optical substrates in the fourth embodiment. It is sectional drawing of the joining optical element formed by bonding together two optical base materials. It is a principal part enlarged view same as the above. FIG. 9 is a cross-sectional view of two optical substrates in a fifth embodiment. It is sectional drawing of the joining optical element formed by bonding together two optical base materials. FIG. 10 is a cross-sectional view of two optical substrates in a sixth embodiment. It is sectional drawing of the joining optical element formed by bonding together two optical base materials. It is A arrow view same as the above. Diagram of the shape change of the optical element when cured with the space filled with resin

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Embodiment 1]
FIG. 1 is a cross-sectional view of two optical substrates 11 and 12 to be bonded together. FIG. 2 is a cross-sectional view of the bonded optical element 10 formed by bonding two optical base materials 11 and 12 together.

In FIG. 1, the optical substrate 11 has a biconcave lens shape. The optical substrate 11 has a the mating surface 13 ₁ bonded with anti adhesion surface 14 _1. Bonding surface 13 _1, the approximate radius of curvature R1a has the aspherical shape of the R1a = 8 mm. Incidentally, the bonding surface 13 ₁ is not limited to the aspherical. For example, it may be a spherical shape (the same applies to other embodiments).

Moreover, anti-bonding surface 14 _1, the approximate radius of curvature R1b has an aspheric shape of R1b = 38mm. Incidentally, the anti-bonding surface 14 ₁ is not limited to be aspherical. For example, it may be a spherical shape (the same applies to other embodiments).

  Here, the “bonding surface” is the surface of the optical substrate that comes into contact with the energy curable resin, and the “anti-bonding surface” is the optical substrate that faces the bonding surface with the substrate interposed therebetween. It is the surface of the material.

This optical substrate 11 is a glass molded lens having a center thickness t ₁ of t ₁ = 0.8 mm and an outer diameter D ₁ of D ₁ = φ12.4 mm.
In the present embodiment, an optical glass material S-BSL7 (manufactured by OHARA INC.) Is used as the optical substrate 11. The optical substrate 11, the outer peripheral portion of the mating surface 13 ₁ bonded with an optical effective diameter D _0, and has a non-contact portion 15 _1. The non-contact portion 15 ₁ is formed in a plane extending in a direction perpendicular to the optical axis O. The outer periphery of the non-contact portion 15 _1, the contact portion 16 ₁ is formed. Here, the non-contact portion 15 ₁ is a plan zonal. However, the non-contact portion 15 ₁ is not necessarily planar and need not be plane extending in a direction perpendicular to the optical axis O. These points are the same in each embodiment described later.

The contact portion 16 ₁ is formed between an outer peripheral surface 11a of the non-contact portions 15 ₁ and the optical substrate 11. In this embodiment, the contact portion 16 ₁ is formed on a slope of 45 ° with respect to the optical axis O. The contact portion 16 ₁ is in contact with the other of the optical substrate 12 on attachment. The contact portion 16 ₁ is mirror-finished by polishing or the like.

In the present embodiment, the contact portion 16 ₁ was 45 ° slope with respect to the optical axis O, it is not limited thereto. For example, the inclination angle may be a value larger than 0 ° and smaller than 90 °. This also applies to each embodiment described later.

Next, the optical substrate 12 has a meniscus lens shape. The optical substrate 12, and a mating surface 13 ₂ anti bonded surface 14 ₂ paste. The bonding surface 13 _2, the approximate radius of curvature R2a has an aspheric shape of R2a = 6.4 mm. Incidentally, the bonding surface 13 ₂ is not limited to the aspherical. For example, it may be a spherical shape (the same applies to other embodiments).

Moreover, anti-bonding surface 14 _2, the approximate radius of curvature R2b has an aspheric shape R2b = 16 mm. Incidentally, the anti-bonding surface 14 ₂ is not limited to the aspherical. For example, it may be a spherical shape (the same applies to other embodiments).

The optical base 12 is a plastic molded lens having a center thickness t ₂ of t ₂ = 2.4 mm and an outer diameter D ₂ of D ₂ = φ12.4 mm.
In the present embodiment, a thermoplastic resin of PC (polycarbonate) resin (Iupizeta EP5000: manufactured by Mitsubishi Gas Chemical Co., Ltd.) is used as the optical substrate 12. The optical substrate 12, the outer peripheral portion of the bonding surface 13 ₂ has an optical effective diameter _{D 0} (see FIG. 2), it has a non-contact portion 15 _2. The non-contact portion 15 ₂ is formed by a plane extending in a direction perpendicular to the optical axis O. The outer periphery of the non-contact portion 15 _2, the contact portion 16 ₂ is formed. Here, the non-contact portion 15 ₂ is a plan of the ring-shaped. However, the non-contact portion 15 ₂ is not necessarily planar and need not be plane extending in a direction perpendicular to the optical axis O. These points are the same in each embodiment described later.

The contact portion 16 ₂ is formed between the outer circumferential surface 12a of the non-contact portion 15 ₂ and the optical substrate 12. In this embodiment, the contact portion 16 ₂ is formed on a slope of 45 ° with respect to the optical axis O. The contact portion 16 ₂ is in contact with the other of the optical substrate 11 on attachment. The contact portion 16 ₂ is mirror-finished by polishing or the like.

In the present embodiment, the contact portion 16 ₂ is set to 45 ° slope with respect to the optical axis O, is not limited thereto. For example, the inclination angle may be a value larger than 0 ° and smaller than 90 °. This also applies to each embodiment described later.

Thus, as shown in FIG. 2, the space between at the time when the optical substrate 11 and the optical substrate 12 is in contact with the contact portion ₁₆ 1, 16 _2, the mating surfaces 13 ₁ and the bonding surface 13 ₂ bonded ( Closed space) 5 is formed. As will be described later, the energy curable resin 1 is filled in the space 5.
The energy curable resin 1 forms a resin layer 2 as a lens layer.

Further, an air layer 18 is formed so as to fill between the contact portions 16 ₁ , 16 ₂ and the resin layer 2. The air layer 18 is formed on the outer peripheral side with respect to the optical effective diameter D ₀ of the cemented optical element 10. The air layer 18 is formed in an annular shape (or ring shape).

  In this case, the resin layer 2 made of the energy curable resin 1 causes volume shrinkage during curing. In the resin layer 2, sink marks are preferentially generated on the contact surface side with the air layer 18. The reason is that no stress that prevents the resin layer 2 from contracting acts from the air layer 18. The sink on the contact surface side with the air layer 18 can compensate for the volume shrinkage of the resin layer 2.

  In the present embodiment, the air layer 18 is uniformly formed over the entire circumference of the bonded optical element 10. Therefore, the above-mentioned sink is also generated uniformly over the entire circumference. For this reason, the stress accompanying the curing shrinkage of the resin layer 2 is also equalized. Thus, the deformation of the optical surfaces of the optical base materials 11 and 12 due to the stress during curing shrinkage is reduced.

Next, a bonding method will be described.
In Figure 1, the bonding surface 13 ₁ of the optical substrate 11, a desired discharge amount of the thermosetting resin as an energy-curable resin 1 by the supply device (not shown). As the energy curable resin 1, for example, an ultraviolet curable resin may be used instead of the thermosetting resin.

Next, the optical substrate 12 is moved closer to the optical substrate 11. Note that the optical substrate 11 may be moved closer to the optical substrate 12. At this time, the contact portion 16 1 of people each there outside the optical effective diameter D ₀ of the optical substrate 11, _12, 16 _2, to押延the thermosetting resin to be fitted to each other. These contact portions 16 _1, 16 ₂ are processed so that the resin layer 2 has a desired resin thickness (central resin thickness t ₀₎ by fitting together.

In the present embodiment, the bonding surfaces 13 ₁ and 13 ₂ are processed with high accuracy with respect to the coaxiality with respect to the optical axis O. Therefore, the optical axis O of the optical substrate 11 and the optical substrate 12 is configured to match by the contact portions ₁₆ 1, 16 ₂ of the optical substrate 11, 12 are fitted to each other.

Furthermore, the optical base materials 11 and 12 are positioned in a direction parallel to the thickness of the resin layer 2 (center resin thickness t _o ) and the optical axis O in a state where the contact portions 16 ₁ and 16 ₂ are fitted. It is determined. In the present embodiment, the discharge amount of the thermosetting resin is such that the diameter in the direction perpendicular to the optical axis of the resin layer 2 is equal to or greater than the optical effective diameter D ₀ . If the diameter in the direction perpendicular to the optical axis of the resin layer 2 is equal to or less than the optical effective diameter D ₀ , sink marks of the resin layer 2 may reach the optical surface and affect the optical performance.

Furthermore, the discharge amount of the thermosetting resin was set to a resin amount necessary for the air layer 18 to remain on the outer peripheral portion of the resin layer 2. In this way, the air layer 18 always remains on the outer peripheral portion of the resin layer 2.
The reason why the air layer 18 is left is to cause sinking preferentially from the contact surface side with the air layer 18 when the resin layer 2 shrinks in volume due to curing. As a result, the volume shrinkage of the resin layer 2 occurs exclusively at the contact portion with the air layer 18. Further, since the contact portion between the resin layer 2 and the air layer 18 is on the outer peripheral side of the optical effective diameter D ₀ , the optical characteristics are not affected.

The optical base material 11 and the optical base material 12 bonded together are put into a heating furnace while maintaining this state. And the optical base materials 11 and 12 were heated at 50 degreeC for 3 hours, and the resin layer 2 was hardened.
At this time, to increase the adhesion of the optical substrate 11 and the resin, the resin and the optical substrate 12, before bonding the substrates to each other, the bonding surface 13 ₁ of the optical substrate 11 was subjected to silane coupling treatment . Also, the bonding surface 13 ₂ of the optical substrate 12 after the hydrophilic treatment by UV ozone treatment was performed with a silane coupling treatment.

Thus, as shown in FIG. 2, the bonded optical element 10 formed by bonding the two optical base materials 11 and 12 had a center resin thickness t ₀ of t ₀ = 0.05 mm. Further, the resin thickness t _{3 in the} direction parallel to the optical axis O at the optically effective diameter D ₀ (D ₀ = φ8.8 mm) of the resin layer 2 was t ₃ = 0.5 mm.

  As described above, in the present embodiment, the resin layer 2 is cured with the annular air layer 18 formed on the outer peripheral portion of the resin layer 2. During this curing, the resin layer 2 undergoes volume shrinkage, but sink marks preferentially occur on the contact surface of the resin layer 2 with the air layer 18.

  Then, sink marks generated on the contact surface with the air layer 18 can compensate for the volume shrinkage of the resin layer 2. For this reason, the stress at the time of hardening shrinkage of the resin layer 2 hardly acts on the optical base materials 11 and 12. Therefore, it is possible to obtain the bonded optical element 10 with high optical surface shape accuracy.

Furthermore, since the air layer 18 is uniformly formed over the entire circumference of the cemented optical element 10, sink marks are also uniformly generated over the entire circumference. For this reason, the stress applied when the resin layer 2 contracts is uniformly applied while maintaining rotational symmetry. Thereby, the shape deterioration of the optical surface of the optical base materials 11 and 12 hardly arises. In this way, the bonded optical element 10 with high surface accuracy of the optical surface can be obtained.
[Embodiment 2]
FIG. 3 is a cross-sectional view of the two optical base materials 21 and 22 to be bonded together. FIG. 4 is a view showing the appearance of the optical base material 22. FIG. 5 is a cross-sectional view of the bonded optical element 20 formed by bonding two optical base materials 21 and 22 together.

  In FIG. 3, the optical substrate 21 is the same as the optical substrate 11 of the first embodiment. For this reason, the same components as those of the optical substrate 11 are denoted by reference numerals obtained by adding 10 to the reference numerals described in the first embodiment, and description thereof is omitted.

  Further, the optical substrate 22 is different from the optical substrate 12 of the first embodiment only in a part of the shape. For this reason, the same components as those of the optical substrate 12 are denoted by reference numerals obtained by adding 10 to the reference numerals described in the first embodiment, and description thereof is omitted.

FIG. 4 shows an external view of the optical base material 22 shown in FIG. 3 in a state where the optical base material 22 is rotated by 180 ° about the axis perpendicular to the optical axis O.
FIG 4 As is clear, the contact portion 26 ₂ of the optical substrate 22, is over the entire periphery not formed. That is, the contact portion 26 ₂ of the optical substrate 22, the circumference is divided equidistantly into the four contact portions ₂₆ 2 -1～26 ₂ -4.

The contact portion ₂₆ 2 -1～26 ₂ -4 respective inner surfaces (the side facing the optical axis O) is formed on a slope of 45 ° with respect to the optical axis O.
Thus, as shown in FIG. 5, the optical base 21 and the optical base 22 are in contact with each other at the contact portions 26 ₁ and 26 ₂ . Then, when the contact portions 26 ₁ and 26 ₂ come into contact with each other, a space 5 is formed between the bonding surface 23 ₁ and the bonding surface 23 ₂ . The space 5 is filled with the energy curable resin 1. Thus, the energy curable resin 1 forms a resin layer 2 as a lens layer.

Further, an air layer 28 is formed so as to fill between the contact portions 26 ₁ and 26 ₂ and the resin layer 2. The air layer 28 is formed on the outer peripheral side of the optical effective diameter D ₀ of the cemented optical element 20. Further, the air layer 28 is communicated with the outside air except for portions of the four contact portions ₂₆ 2 -1～26 ₂ -4. That is, the air layer 28 is not a closed space (open space).

  Moreover, when the resin layer 2 hardens | cures, the air layer 28 exists over the perimeter of the outer peripheral part. Then, sink marks are preferentially generated in the resin layer 2 on the contact surface side with the air layer 28. This is because, as described above, stress that prevents contraction does not act from the air layer 28. Thus, sink marks on the contact surface side with the air layer 28 compensate for the volume shrinkage of the resin layer 2.

Further, the air layer 28 communicates with the outside air, and even if the resin layer 2 contracts, the air can be replenished from the outside air. For this reason, the ease of sinking on the contact surface side with the air layer 28 increases when the resin layer 2 is cured. Moreover, the contact portion between the resin layer 2 and the air layer 28, nor affect the optical properties of the optical surface since the outer peripheral side of the optical effective diameter D _0.

For this reason, the deformation of the optical surfaces of the optical base materials 21 and 22 accompanying the stress at the time of curing shrinkage of the resin layer 2 is further reduced.
Next, since the bonding method is the same as that of the first embodiment, description thereof is omitted.

As shown in FIG. 5, the bonded optical element 20 formed by bonding the two optical base materials 21 and 22 has a center resin thickness t ₀ of t ₀ = 0.05 mm, as in the first embodiment. Met. The resin thickness t _{3 in the} direction parallel to the optical axis O at the optically effective diameter D ₀ (D ₀ = φ8.8 mm) of the resin layer 2 was t ₃ = 0.5 mm.

In the present embodiment, the air layer 28 on the outer periphery of the resin layer 2 communicates with the outside air instead of the closed space. For this reason, according to the present embodiment, the ease of sinking the contact surface with the air layer 28 when the resin layer 2 is cured further increases, and the volume shrinkage of the resin layer 2 is almost at the contact surface with the air layer 28. appear. Thus, the in the optical effective diameter D ₀ of the cemented optical element 20 effects not reach, bonding the optical element 20 can maintain a good optical performance.
[Embodiment 3]
FIG. 6 is a cross-sectional view of the two optical base materials 31 and 32 to be bonded together. FIG. 7 is a cross-sectional view of an intermediate bonded optical element 30 ′ formed by bonding two optical base materials 31 and 32 together.

In FIG. 6, an optical substrate 31 is substantially the same as the optical substrate 11 of the first embodiment. However, the contact portion 36 ₁ of the optical substrate 31 is different from the point that is formed on the rough surface having minute uneven portion (sand shear plane). For this reason, the same components as those of the optical substrate 11 are denoted by reference numerals obtained by adding 20 to the reference numerals described in the first embodiment, and description thereof is omitted.

The optical substrate 32 has a biconvex lens shape. The optical substrate 32 has bonded with the mating surface 33 _2, and a bonding surface 34 ₂ opposed through the optical substrate 32 in the bonding surface 33 _2. The bonding surface 33 _2, the approximate radius of curvature R2a has an aspheric shape of R2a = 6.4 mm.

Also, the mating surfaces 34 ₂ paste is approximated curvature radius R2b has an aspheric shape R2b = 9 mm. This optical substrate 32 is a plastic molded lens having a center thickness t ₂ of t ₂ = 4 mm and an outer diameter D ₂ of D ₂ = φ12.4 mm.

In the present embodiment, a thermoplastic resin of PC (polycarbonate) resin (Iupizeta EP5000: manufactured by Mitsubishi Gas Chemical Company, Inc.) is used as the optical substrate 32. The optical substrate 32 in the outer peripheral portion of the optical effective diameter _{D 0} mating surface 33 adhered with each (see FIG. 7) ₂ and the bonding surface 34 _2, bonding the other of the optical substrate at 31, 31 '(FIG. 8 Non-contact portions 35 ₂ and 35 ₃ that do not contact the reference). The non-contact portions 35 ₂ and 35 ₃ are formed on a plane extending perpendicular to the optical axis O.

Further, on the outer peripheral portion of the non-contact portion ₃₅ 2, 35 _3, and a contact portion ₃₆ 2, 36 _{3. On} the surfaces of the contact portions 36 ₂ , 363, rough surfaces (sand-slip surfaces) having fine uneven portions are formed. In the present embodiment, these contact portions 36 _2, 36 ₃ are formed on a slope of 45 ° with respect to the optical axis O.

Contact portion 36 ₂ of the bonding surface ₃₃₂ side, a portion in contact with the contact portion 36 ₁ of the other optical substrate 31 on attachment. (As will be described later, the mating surface 34 ₂ side of the contact portion 36 ₃ Paste is a portion in contact with the ₁ 'contact portion 36' of the other optical substrate 31 on attachment.)
In this embodiment, the contact portions 36 ₁ and the contact portion 36 ₂ is formed on the rough surface (sand shear plane), the contact surface between the contact portions 36 ₁ and the contact portion 36 ₂ of the fine concavo-convex portion It is the point contact state which contacts between convex parts. For this reason, the space 5 to be described later is in communication with the outside air via the contact surface.

Thus, as shown in FIG. 7, when the optical substrate 31, 32 are in contact with the contact portion ₃₆ 1, 36 _2, the space 5 between the mating surfaces 33 ₂ and Paste mating surface 33 ₁ bonded formed The The space 5 is filled with the energy curable resin 1. The energy curable resin 1 forms a resin layer 2 as a lens layer.

Further, an air layer 38 is formed so as to fill between the contact portions 36 ₁ and 36 ₂ and the resin layer 2. The air layer 38 is formed on the outer peripheral side than the optical effective diameter D ₀ of the intermediate cemented optical element 30 '. The air layer 38 is formed in an annular shape (or ring shape).

  In this case, as described above, the resin layer 2 undergoes volume shrinkage during curing. In addition, sink marks are preferentially generated in the resin layer 2 on the contact surface side with the air layer 38. The sink on the contact surface side with the air layer 38 can compensate for the volume shrinkage of the resin layer 2.

  Moreover, since the air layer 38 is formed in an annular shape, sink marks are uniformly generated over the entire circumference. For this reason, the deformation of the optical surfaces of the optical base materials 31 and 32 due to the stress accompanying the curing shrinkage of the resin layer 2 is reduced.

Next, a bonding method will be described.
The bonding surface 33 ₁ of the optical substrate 31, a desired discharge amount of the thermosetting resin as an energy-curable resin 1 by the supply device (not shown).

Next, the optical substrate 32 is moved closer to the optical substrate 31.
At this time, the thermosetting resin is stretched until the contact portions 36 ₁ and 36 ₂ outside the optical effective diameter D ₀ of the optical base materials 31 and 32 are fitted to each other. The contact portions 36 ₁ and 36 ₂ are processed so that the resin layer 2 has a desired resin thickness (center resin thickness t ₀ ) by fitting with each other.

In the present embodiment, the bonding surfaces 33 ₁ and 33 ₂ are processed with high accuracy with respect to the coaxiality with respect to the optical axis O. Therefore, the optical axis O of the optical substrate 31, 32 is configured to match by the contact portions ₃₆ 1, 36 ₂ of the optical substrate 31, 32 are fitted to each other.

Furthermore, the optical base materials 31 and 32 are determined in positions parallel to the thickness of the resin layer 2 and the optical axis O in a state where the contact portions 36 ₁ and 36 ₂ are fitted. In the present embodiment, the discharge amount of the thermosetting resin is such that the diameter in the direction perpendicular to the optical axis of the resin layer 2 is equal to or greater than the optical effective diameter D ₀ . If the diameter in the direction perpendicular to the optical axis of the resin layer 2 is equal to or less than the optical effective diameter D ₀ , sink marks of the resin layer 2 may affect the optical performance.

Further, the discharge amount of the thermosetting resin was set to a resin amount necessary for the air layer 38 to remain on the outer peripheral portion of the resin layer 2. Thus, the air layer 38 is always left on the outer peripheral portion of the resin layer 2.
As a result, the volume shrinkage of the resin layer 2 occurs exclusively at the contact portion with the air layer 38. The contact portion between the resin layer 2 and the air layer 38, nor affect the optical characteristics since the outer peripheral side of the optical effective diameter D _0.

The optical base material 31 and the optical base material 32 bonded together are put into a heating furnace while maintaining this state. And the optical base materials 31 and 32 were heated at 50 degreeC for 3 hours, and the resin layer 2 was hardened.
At this time, to increase the adhesion of the optical substrate 31 and the resin, the resin and the optical substrate 32, before bonding, bonding surface 33 ₁ of the optical substrate 31 was subjected to silane coupling treatment. Also, the bonding surface 33 ₂ of the optical substrate 32 after the hydrophilic treatment by UV ozone treatment was performed with a silane coupling treatment.

Thus, as shown in FIG. 7, the intermediate bonded optical element 30 ′ formed by bonding the two optical base materials 31 and 32 had a center resin thickness t ₀ of t ₀ = 0.05 mm. Further, the resin thickness t _{3 in the} direction parallel to the optical axis at the optical effective diameter D ₀ (D ₀ = φ8.8 mm) of the resin layer 2 was t ₃ = 0.5 mm.

  Next, FIG. 8 is a cross-sectional view of the intermediate bonding optical element 30 ′ and the optical base material 31 ′ to be bonded together. The intermediate bonding optical element 30 'is inverted upside down. FIG. 9 is a cross-sectional view of the bonded optical element 30 formed by bonding the intermediate bonded optical element 30 ′ and the optical base material 31 ′.

In FIG. 8, the optical substrate 31 ′ has a plano-concave lens shape. This optical substrate 31 ′ has a bonding surface 33 ₁ ′ and an anti-bonding surface 34 ₁ ′. The bonding surface 33 ₁ ′ has an aspherical shape with an approximate curvature radius R1a of R1a = 10 mm.

Further, the anti-bonding surface 34 ₁ ′ has a planar shape. This optical substrate 31 ′ is a glass molded lens having a center thickness t ₁ of t ₁ = 1.7 mm and an outer diameter D ₁ of D ₁ = φ12.4 mm. In the present embodiment, an optical glass material S-BSL7 (manufactured by OHARA INC.) Is used as the optical substrate 31 ′. This optical base material 31 ′ has a non-contact portion 35 ₁ ′ on the outer peripheral portion of the bonding surface 33 ₁ ′. The non-contact portion 35 ₁ ′ is formed on a plane extending perpendicular to the optical axis O. A contact portion 36 ₁ ′ is formed on the outer peripheral portion of the non-contact portion 35 ₁ ′.

This contact part 36 ₁ ′ is formed between the non-contact part 35 ₁ ′ and the outer peripheral surface 31 a ′ of the optical substrate 31 ′. In the present embodiment, the contact portion 36 ₁ ′ is formed on a slope of 45 ° with respect to the optical axis O. The contact portions 36 1 _'is in contact with the contact portion 36 ₃ of the other optical substrate 32 on attachment. The surface of the contact portion 36 ₁ ′ is finished to be a rough surface (sand-slip surface) having fine uneven portions.

Next, a bonding method will be described.
A desired amount of thermosetting resin as the energy curable resin 1 is discharged onto the bonding surface 33 ₁ ′ of the optical base 31 ′ by a supply device (not shown). Next, the optical substrate 32 of the intermediate bonding optical element 30 ′ is moved closer to the optical substrate 31 ′.

At this time, optical substrate 31 ', 32 contact portion 36 ₁ which is outside the optical effective diameter D ₀ of the' ₃₆₃ is to押延the thermosetting resin to be fitted to each other. The contact portions 36 ₁ ′ and 36 ₃ are processed so that the resin layer 3 has a desired resin thickness (center resin thickness t ₀ ) by fitting with each other.

Further, in the present embodiment, the bonding surface 33 ₁ ', 34 _2, coaxiality with respect to the optical axis O is processed with high precision. Therefore, optical substrate 31 'the optical axis of the optical substrate 32, optical substrate 31', the contact portions 36 ₁ of 32 ', so as to match by 36 ₃ are fitted to each other.

Further, the optical substrate 31 ', 32, the contact portions 31 ₁ of each', 36 in a state in _which the ₃ fitted, the position of the parallel direction and the perpendicular direction to the optical axis O of the resin layer 2 is determined. In the present embodiment, the discharge amount of the thermosetting resin is set such that the diameter with respect to the optical axis O of the resin layer 2 is not less than the optical effective diameter D ₀ . For optical effective diameter D ₀ or less, there is a fear that shrinkage of the resin layer 2 affects the optical performance.

Furthermore, the discharge amount of the thermosetting resin was set to a resin amount necessary for the air layer 39 to remain on the outer peripheral portion of the resin layer 2. In this way, the air layer 39 is always left on the outer peripheral portion of the resin layer 2.
While maintaining this state, the bonded optical base material 31 ′ and intermediate bonded optical element 30 ′ were placed in a heating furnace and heated at 50 ° C. for 30 minutes to cure the resin layer 3.

In addition, in order to raise the adhesiveness of optical base material 31 'and resin, resin, and optical base material 32, the bonding surface 33 ₁ ' of optical base material 31 'performed the silane coupling process before bonding. Also, the bonding surface 34 ₂ of the optical substrate 32 after the hydrophilic treatment by UV ozone treatment was performed with a silane coupling treatment.

Thus, as shown in FIG. 9, the bonded optical element 30 formed by bonding the optical substrate 31 ′ and the intermediate bonded optical element 30 ′ had a center resin thickness t ₀ of t ₀ = 0.07 mm. Further, the resin thickness t _{3 in the} direction parallel to the optical axis O at the optically effective diameter D ₀ (D ₀ = φ8.8 mm) of the resin layer ₃ was t ₃ = 0.2 mm.

According to the present embodiment, since each contact portion 36 ₁ , 36 ₂ , 36 ₃ , 36 ₁ ′ is formed on a rough surface having fine uneven portions, it corresponds to the volume increase of the air layers 38, 39 due to the occurrence of sink marks. air becomes liable to be compensated from the contact portions 36 ₁ and the like. For this reason, the shape deterioration of each bonding surface of the optical base materials 31, 32, 31 ′ could be further suppressed.
[Embodiment 4]
FIG. 10 is a cross-sectional view of the two optical base materials 41 and 42 to be bonded together. FIG. 11 is a cross-sectional view of a bonded optical element 40 formed by bonding two optical base materials 41 and 42 together. FIG. 12 is an enlarged view of a main part of FIG.

In FIG. 10, the optical substrate 41 has a concave meniscus lens shape. The optical substrate 41 has a the mating surface 43 ₁ bonded with anti adhesion surface 44 _1. Bonding surface 43 _1, the approximate radius of curvature R1a has the aspherical shape of the R1a = 12 mm.

Moreover, anti-bonding surface 44 _1, the approximate radius of curvature R1b has an aspheric shape of R1b = 20 mm.
This optical substrate 41 is a plastic molded lens having a center thickness t ₁ of t ₁ = 1 mm and an outer diameter D ₁ of D ₁ = φ20 mm.

In the present embodiment, a thermoplastic resin of PC (polycarbonate) resin (Iupizeta EP5000: manufactured by Mitsubishi Gas Chemical Co., Ltd.) is used as the optical substrate 41. The optical substrate 41, the outer peripheral portion of the bonding surface 43 ₁ has an optical effective diameter D _{0 (see} FIG. 11), has a non-contact portion 45 ₁ which is not in contact with the other optical substrate 42 on attachment Yes. The non-contact portion 45 ₁ is formed in a plane extending perpendicularly to the optical axis O.

Further, on the outer peripheral portion of the non-contact portion 45 ₁ has a first contact portion 46 _1. The first contact portion 46 ₁ is formed on the slopes of 30 ° with respect to the optical axis O. Furthermore, this first outer peripheral portion of the contact portion 46 _1, and has a second contact portion 47 _1.

Contact portion 47 ₁ of the second is formed in a plane extending perpendicularly to the optical axis O. These first and second contact portions ₄₆ 1, 47 ₁ is the other of the first and second contact portions ₄₆ 2, 47 ₂ and the portion which contacts the optical substrate 42 on attachment.

The optical substrate 42 has a biconvex lens shape. The optical substrate 42 has a the mating surface 43 ₂ bonded with anti adhesion surface 44 _2. The bonding surface 43 _2, the approximate radius of curvature R2a has an aspheric shape of R2a = 13 mm.

Moreover, anti-bonding surface 44 _2, the approximate radius of curvature R2b has an aspheric shape R2b = 80 mm.
This optical base material 42 is a plastic molded lens having a center thickness t ₂ of t ₂ = 5 mm and an outer diameter D ₂ of D ₂ = φ20 mm.

In the present embodiment, a thermoplastic resin of COP (cycloolefin polymer) resin (ZEONEX 480R: manufactured by Nippon Zeon Co., Ltd.) is used as the optical substrate 42.
The optical substrate 42, the outer peripheral portion of the bonding surface 43 ₂ has an optical effective diameter _{D 0} (see FIG. 11), and a non-contact portion 45 ₂ via a step surface 49. The step surface 49 is formed in a plane parallel to the optical axis O. The non-contact portion 45 ₂ is formed in a plane extending perpendicularly to the optical axis O.

This on the outer peripheral portion of the non-contact portion 45 _2, the first contact portion 46 ₂ is formed. Further includes a second contact portion 47 ₂ in the outer peripheral portion of the first contact portion 46 _2.
The first contact portion 46 ₂ is formed on the slopes of 30 ° to the optical axis O. The second contact portion 47 ₂ is formed in a plane extending perpendicularly to the optical axis O.

Thus, as shown in FIG. 11, the optical substrate 41 and the optical substrate 42 are in contact with each other at the first contact portions 46 ₁ and 46 ₂ and the second contact portions 47 ₁ and 47 ₂ , respectively. At this point, the closed space 5 between the mating surfaces 43 ₂ and Paste mating surface 43 ₁ paste is formed. The closed space 5 is filled with the energy curable resin 1. The energy curable resin 1 forms a resin layer 2 as a lens layer.

Further, as shown in FIG. 12, an air reservoir 48 is formed between the outer peripheral portions of the bonding surfaces 43 ₁ and 43 ₂ , the first contact portions 46 ₁ and 46 ₂ , and the non-contact portions 45 ₁ and 45 _2. It is formed in an annular shape. A part 2 a on the outer peripheral side of the resin layer 2 enters the air reservoir 48 with the air layer remaining.

Next, a bonding method will be described.
10, the bonding surface 43 ₁ of the optical substrate 41, a desired amount of ejecting ultraviolet curable resin as an energy-curable resin 1 by the supply device (not shown).

Next, the optical substrate 42 is moved closer to the optical substrate 41.
At this time, UV curing is performed until the first contact portions 46 ₁ and 46 ₂ and the second contact portions 47 ₁ and 47 ₂ outside the optical effective diameter D ₀ of the optical base materials 41 and 42 are fitted to each other. Stretch the mold resin. The first contact portions 46 ₁ and 46 ₂ and the first contact portions 47 ₁ and 47 ₂ are processed to have a desired resin thickness (center resin thickness t ₀ ) by fitting.

In addition, the first contact portions 46 ₁ and 46 ₂ and the second contact portions 47 ₁ and 47 ₂ are processed so that the coaxiality with respect to the optical axis O is highly accurate. Therefore, the optical axis O of the optical substrate 41 and the optical base 42, so as to match by the contact portions 46 1 of the optical substrate 41 and the optical substrate _42, 46 _2, etc. are fitted to each other Yes.

Further, the optical base materials 41 and 42 are determined so that their positions in the direction parallel to and perpendicular to the optical axis O of the resin layer 2 are determined in a state where the respective contact portions 46 ₁ and 46 ₂ are fitted. It has become.
In this embodiment, as shown in FIG. 11, the discharge amount of the ultraviolet curable resin, the diameter of the resin layer 2 was set to be optically effective diameter D ₀ or more.

Further, the discharge amount of the ultraviolet curable resin was set to an amount necessary for the air layer to remain in the air reservoir 48 at the outer peripheral portion of the resin layer 2. Thus, an air layer is formed on the outer peripheral portion of the resin layer 2.
The volume of the closed space 5 at this time can be accurately calculated at the design stage. On the other hand, the discharge amount of the ultraviolet curable resin may vary. Even in the case where variations occur as described above, as shown in FIG. 12, a part of the excess resin 2a is pushed out to the air reservoir 48, and the discharge amount is such that an air layer remains in the air reservoir 48. .

While maintaining this state, the ultraviolet lamp 4 irradiates ultraviolet rays from below the optical substrate 41 through the optical substrate 41. Irradiation of ultraviolet rays was performed for 80 seconds with an almost uniform illuminance distribution of 15 ± ² mW / cm ² . By this irradiation, the resin layer 2 is cured and becomes a lens layer.

In the present embodiment, a process for increasing the adhesion between the optical substrate 41 and the resin, and the resin and the optical substrate 42 is performed. That is, before bonding, bonding surface ₄₃ 1 of each of the optical substrate 41, 43 ₂ was subjected to a hydrophilic treatment by UV ozone treatment. Further, silane coupling treatment was then performed.

Furthermore, as shown in FIG. 11, the bonded optical element 40 formed by bonding the two optical substrates 41 and 42 has a center resin thickness t ₀ of t ₀ = 0.5 mm, and the optical efficiency of the resin layer 2 The resin thickness t _{3 in the} direction parallel to the optical axis O at the diameter D ₀ (D ₀ = φ15 mm) was t ₃ = 0.25 mm.

  According to the present embodiment, sink marks are preferentially generated on the contact surface with the air layer remaining in the air reservoir 48 on the outer peripheral side of the resin layer 2 when the resin layer 2 is cured. Due to this sink, volume shrinkage of the resin layer 2 occurs exclusively at the contact portion with the air reservoir 48. Furthermore, since the air reservoir 48 is formed uniformly over the entire circumference, sink marks are also uniformly generated over the entire circumference. For this reason, stress which is biased to the resin layer 2 is not generated.

In addition, according to the present embodiment, even if the discharge amount of the ultraviolet curable resin is large, the capacity of the air reservoir 48 is increased, so that the air layer of the air reservoir 48 can be reliably secured. . For this reason, a highly accurate resin discharge mechanism is not required, and the discharge mechanism can be simplified.
[Embodiment 5]
FIG. 13 is a cross-sectional view of two optical substrates 51 and 52 to be bonded together. FIG. 14 is a cross-sectional view of a bonded optical element 50 formed by bonding two optical substrates 51 and 52 together.

The optical substrate 51 has a concave meniscus lens shape. The optical substrate 51 has a the mating surface 53 ₁ bonded with anti adhesion surface 54 _1. Bonding surface 53 _1, the approximate radius of curvature R1a has the aspherical shape of the R1a = 12 mm.

Moreover, anti-bonding surface 54 _1, the approximate radius of curvature R1b has an aspheric shape of R1b = 20 mm.
This optical substrate 51 is a plastic molded lens having a center thickness t ₁ of t ₁ = 1 mm and an outer diameter D ₁ of D ₁ = φ20 mm.

In the present embodiment, a thermoplastic resin of PC (polycarbonate) resin (Iupizeta EP5000: manufactured by Mitsubishi Gas Chemical Co., Ltd.) is used as the optical substrate 51. The optical substrate 51, the outer peripheral portion of the bonding surface 53 ₁ has an optical effective diameter D _{0 (see} FIG. 14), has a non-contact portion 55 ₁ which is not in contact with the other optical substrate 52 on attachment Yes. The non-contact portion 55 ₁ is formed on a plane perpendicular to the optical axis O.

Further, the outer peripheral portion of the non-contact portion 55 ₁ has a first contact portion 56 _1. Contact portion 56 ₁ of the first is formed on a plane parallel to the optical axis O. Further, the outer peripheral portion of the first contact portion 56 _1, and has a second contact portion 57 _1.

Contact portion 57 ₁ of the second is formed in a plane perpendicular to the optical axis O. These first and second contact portions ₅₆ 1, 57 ₁ is the other of the first and second contact portions ₅₆ 2, 57 ₂ and the portion which contacts the optical substrate 52 on attachment.

The optical substrate 52 has a biconvex lens shape. The optical substrate 52 has a the mating surface 53 ₂ bonded with anti adhesion surface 54 _2. The bonding surface 53 _2, the approximate radius of curvature R2a has an aspheric shape of R2a = 13 mm.

Moreover, anti-adhesion surface ₅₄₂ is the approximate radius of curvature R2b has an aspheric shape R2b = 80 mm. This optical substrate 52 is a plastic molded lens having a center thickness t ₂ of t ₂ = 5 mm and an outer diameter D ₂ of D ₂ = φ20 mm.

In the present embodiment, a thermoplastic resin of PMMA (acrylic) resin (Delpet 80N: manufactured by Asahi Kasei Chemicals Corporation) is used as the optical substrate 52.
The optical substrate 52, the outer peripheral portion of the bonding surface 53 ₂ has an optical effective diameter _{D 0} (see FIG. 14), and a non-contact portion 55 ₂ via a step surface 59. The step surface 59 is formed on a surface inclined with respect to the optical axis O. Non-contact portion 55 ₂ is formed in a plane perpendicular to the optical axis O. Further, on the outer peripheral portion of the non-contact portion 55 _2, the first contact portion 56 ₂ is formed. Further includes a second contact portion 57 ₂ in the outer peripheral portion of the first contact portion 56 _2.

The first contact portion 56 ₂ is formed on the optical axis O and parallel planes. The second contact portion 57 ₂ is formed in a plane perpendicular to the optical axis O.
In addition, the non-contact portion 55 _2, the air hole 52a extending parallel to the optical axis O are formed. The air hole 52a communicates with the outside air after the optical substrate 51 and the optical substrate 52 are bonded together, and also communicates with an air reservoir 58 described later. Thereby, the air reservoir 58 does not become negative pressure.

Thus, as shown in FIG. 14, the optical base 51 and the optical base 52 come into contact with each other at the first contact portions 56 ₁ and 56 ₂ and the second contact portions 57 ₁ and 57 ₂ . At this point, the closed space 5 between the mating surfaces 53 ₂ and Paste mating surfaces 53 ₁ paste is formed. The closed space 5 is filled with the energy curable resin 1. The energy curable resin 1 forms a resin layer 2 as a lens layer.

Furthermore, between the bonding surface ₅₃ 1, 53 contact portion ₅₆ first outer circumference portion and the first of _2, 56 _2, the air reservoir portion 58 is formed in an annular shape.
Next, a bonding method will be described.

The bonding surface 53 ₁ of the optical substrate 51, a desired amount of ejecting ultraviolet curable resin as an energy-curable resin 1 by the supply device (not shown).
Next, the optical substrate 52 is moved closer to the optical substrate 51.

At this time, UV curing is performed until the first contact portions 56 ₁ and 56 ₂ and the second contact portions 57 ₁ and 57 ₂ outside the optical effective diameter D ₀ of the optical base materials 51 and 52 are fitted to each other. Stretch the mold resin. By contacting portion ₅₆ 1 of the first, 56 ₂ and the second contact portion ₅₇ 1, 57 ₂ are fitted, bonded optical element 50 is processed to have a desired resin thickness (central resin thickness _{t 0)} Has been.

In addition, the first contact portions 56 ₁ and 56 ₂ (and the second contact portions 57 ₁ and 57 ₂ ) are processed so that the coaxiality with respect to the optical axis O is highly accurate. For this reason, the optical axes O of the optical substrate 51 and the optical substrate 52 come to coincide with each other when the contact portions 56 ₁ and 56 ₂ of the optical substrate 51 and the optical substrate 52 are fitted to each other. Yes.

Further, the discharge amount of the ultraviolet curable resin is set to a resin amount necessary for the diameter in the direction perpendicular to the optical axis O of the resin layer 2 to be equal to or larger than the optical effective diameter D ₀ and for the air layer to remain in the air reservoir 58. . At this time, optical substrate 51 and the optical base 52 are fitted at the contact portion 56 _1, 56 _2, etc., it is a state where the position of the parallel direction and the perpendicular direction to the optical axis O of the resin layer 2 has been determined.

Thus, an air layer was formed on the outer peripheral portion of the resin layer 2.
The volume of the closed space 5 at this time can be accurately calculated at the design stage. On the other hand, the discharge amount of the ultraviolet curable resin may vary. Even when variations occur in this way, the discharge amount is set such that an excess air is pushed out to the air reservoir 58 and an air layer is formed.

While maintaining this state, the ultraviolet lamp 4 irradiates ultraviolet rays from below the optical substrate 51 through the optical substrate 51. Irradiation of ultraviolet rays was performed for 80 seconds with an almost uniform illuminance distribution of 15 ± ² mW / cm ² . By this irradiation, the resin layer 2 is cured and a lens layer is formed.

In the present embodiment, processing for increasing the adhesion between the optical base 51 and the resin, and the resin and the optical base 52 is performed. That is, before the bonding, the bonding surfaces 53 ₁ and 53 ₂ of the optical base materials 51 and 52 were subjected to hydrophilic treatment by ultraviolet ozone treatment. Further, silane coupling treatment was then performed.

As shown in FIG. 14, the bonded optical element 50 formed by bonding two optical base materials 51 and 52 has a center resin thickness t ₀ of t ₀ = 0.5 mm, and an optical effective diameter D of the resin layer 2. The resin thickness t _{3 in the} direction parallel to the optical axis O at ₀ (D ₀ = φ15 mm) was t ₃ = 0.25 mm.

According to this embodiment, the first contact portion 56 _1, 56 ₂ due to a plane parallel to the optical axis O, it is possible to improve the tilting direction of the bonded accuracy during bonding. That is, the two optical base materials 51 and 52 are not bonded in a wedge shape.

Furthermore, since the air layer and the outside air communicate with each other through the air holes 52a, the bonding optical element 50 can prevent the change in the internal pressure of the air layer caused by the environmental change (temperature change). In this way, peeling of the bonding surface due to environmental changes can be avoided.
[Embodiment 6]
FIG. 15 is a cross-sectional view of two optical substrates 61 and 62 to be bonded together. FIG. 16 is a cross-sectional view of a bonded optical element 60 formed by bonding two optical base materials 61 and 62 together. FIG. 17 is a view as seen from an arrow A in FIG.

  The optical base 61 is different from the optical base 51 shown in the fifth embodiment in that air holes (two places) 61a are provided. The air hole 61a has a rectangular cross section. However, the shape is not limited to a rectangular cross section.

  Moreover, the optical base material 62 has the same configuration as the optical base material 52 shown in the fifth embodiment. For this reason, in the optical base materials 61 and 62, the same components as those of the optical base materials 51 and 52 of the fifth embodiment are denoted by reference numerals obtained by adding 10 to the reference numerals, and description thereof is omitted.

Next, a method for bonding the optical substrate 61 and the optical substrate 62 will be described.
15, the bonding surface 63 ₁ of the optical substrate 61, a desired amount of ejecting ultraviolet curable resin as an energy-curable resin 1 by the supply device (not shown).

Next, the optical substrate 62 is moved closer to the optical substrate 61.
At this time, UV curing is performed until the first contact portions 66 ₁ and 66 ₂ and the second contact portions 67 ₁ and 67 ₂ outside the optical effective diameter D ₀ of the optical bases 61 and 62 are fitted to each other. Stretch the mold resin. The first contact portions 66 ₁ and 66 ₂ and the second contact portions 67 ₁ and 67 ₂ are processed so that the bonded optical element 60 has a desired resin thickness (center resin thickness t ₀ ) by fitting. Has been.

In addition, the first contact portions 66 ₁ and 66 ₂ (and the second contact portions 67 ₁ and 67 ₂ ) are processed so that the coaxiality with respect to the optical axis O is highly accurate. For this reason, the optical axes O of the optical base 61 and the optical base 62 coincide with each other when the contact portions 66 ₁ , 66 _2, etc. of the optical base 61 and the optical base 62 are fitted to each other. ing.

Further, as shown in FIG. 16, the discharge amount of the ultraviolet curable resin is larger than the optical axis O of the resin layer 2 and has a diameter perpendicular to or larger than the optical effective diameter D ₀ and an air layer remains in the air reservoir 68. The amount required for At this time, the optical base 61 and the optical base 62 are fitted with the contact portions 66 ₁ , 66 _2, etc., and the thickness of the resin layer 2 and the position in the optical axis O direction are determined.

Thus, an air layer was reliably formed on the outer peripheral portion of the resin layer 2. In this case, as shown in FIGS. 16 and 17, the air layer communicates with the air hole 61a. For this reason, the air layer communicates with the outside air and does not become negative pressure. Therefore, sink marks are preferentially generated in the resin layer 2 from the contact surface side with the air layer. Further, since the contact portion between the resin layer 2 and the air layer is on the outer peripheral side of the optical effective diameter D ₀ , this sink does not affect the optical characteristics.

While maintaining this state, the ultraviolet lamp 4 irradiates ultraviolet rays from below the optical substrate 61 through the optical substrate 61. Irradiation of ultraviolet rays was performed for 80 seconds with an almost uniform illuminance distribution of 15 ± ² mW / cm ² . By this irradiation, the resin layer 2 is cured and a lens layer is formed.

In the present embodiment, a process for increasing the adhesion between the optical base 61 and the resin, and the resin and the optical base 62 is performed. That is, before bonding, the bonding surfaces 63 ₁ and 63 ₂ of the optical substrates 61 and 62 were subjected to hydrophilic treatment by ultraviolet ozone treatment. Further, silane coupling treatment was then performed.

Furthermore, as shown in FIG. 16, the bonded optical element 60 formed by bonding the two optical substrates 61 and 62 has a center resin thickness t ₀ of t ₀ = 0.5 mm, and the optically effective resin layer 2 The resin thickness t _{3 in the} direction parallel to the optical axis O at the diameter D ₀ (D ₀ = φ15 mm) was t ₃ = 0.25 mm.

  According to the present embodiment, since two air holes 61a are provided on the side surface of the optical base 61, the influence on the optical surfaces of the optical bases 61 and 62 when the resin layer 2 is molded can be eliminated. . For this reason, it is possible to increase the accuracy of the optical surface shape of the optical substrates 61 and 62 themselves.

  Note that the shape and material of the optical base material and the type of resin described in each of the embodiments described above are not limited thereto.

DESCRIPTION OF SYMBOLS 1 Energy curable resin 2 Resin layer 2a Part on the outer peripheral side of resin layer 3 Resin layer 4 Ultraviolet lamp 5 Space 10 Bonding optical element 11 Optical base material 11a Outer peripheral surface 12 Optical base material 12a Outer peripheral surface 13 ₁ Bonding surface 13 ₂ Bonding surface 14 ₁ Anti-bonding surface 14 ₂ Anti-bonding surface 15 ₁ Non-contact portion 15 ₂ Non-contact portion 16 ₁ Contact portion 16 ₂ Contact portion 18 Air layer 20 Bonding optical element 21 Optical substrate 22 Optical substrate 23 ₁ Bonding surface 23 ₂ Bonding surface 24 ₁ Anti-bonding surface 24 ₂ Anti-bonding surface 25 ₁ Non-contact portion 25 ₂ Non-contact portion 26 ₁ Contact portion 26 ₂ Contact portion 28 Air layer 30 Bonding optical element 30 ′ Intermediate bonding optics Element 31 Optical substrate 32 Optical substrate 31 ′ Optical substrate 31a ′ Outer peripheral surface 33 ₁ Bonding surface 33 ₁ ′ Bonding surface 33 ₂ Bonding surface 34 ₁ Anti-bonding surface 34 ₁ ′ Anti-bonding Laminating surface 34 ₂ Laminating surface 35 ₁ Non-contact portion 35 ₁ 'Non-contact portion 35 ₂ Non-contact portion 36 ₁ Contact portion 36 ₁ ' Contact portion 36 ₂ Contact portion 38 Air layer 39 Air layer 40 Bonding optical element 41 Optical base material 42 optical substrate 43 ₁ bonding surface 43 ₂ bonding surface 44 ₁ anti-bonding surface 44 ₂ anti-bonding surface 45 ₁ non-contact portion 45 ₂ non-contact portion 46 ₁ first contact portion 46 ₂ first contact portion 47 ₁ 2nd contact part 47 ₂ 2nd contact part 48 Air accumulation part 49 Step surface 50 Bonding optical element 51 Optical base material 52 Optical base material 52a Air hole 53 ₁ Bonding surface 53 ₂ Bonding surface 54 ₁ Anti-bonding Matching surface 54 ₂ Anti-bonding surface 55 ₁ Non-contact portion 55 ₂ Non-contact portion 56 ₁ First contact portion 56 ₂ First contact portion 57 ₁ Second contact portion 57 ₂ Second contact portion 58 Air reservoir 59 Stepped surface 60 Bonded optical element 61 optical substrate 61a air hole 62 the optical substrate 63 ₁ bonded surface 63 ₂ bonding surface 64 _first reaction bonding surface 64 _second reaction bonding surface 65 ₁ non-contact portion 65 ₂ non-contact portion 66 ₁ a first contact portion 66 ₂ 1st contact part 67 ₁ 2nd contact part 67 ₂ 2nd contact part 68 Air reservoir part 69 Level surface 101 Energy curable resin 102 Resin layer 111 Optical base material 112 Optical base material

Claims (7)

Two optical substrates that are in contact with each other through the contact portion outside the effective optical diameter;
A lens layer made of an energy curable resin disposed between the two optical substrates;
An air layer formed between the optical substrate and the lens layer;
A bonded optical element comprising: 2. The bonded optical element according to claim 1, wherein, of the at least two optical substrates, at least one of the opposing contact portions is divided into a plurality of portions outside the effective optical diameter. . The cemented optical element according to claim 1, wherein the air layer is formed in a ring shape. The cemented optical element according to claim 2, further comprising an air hole that communicates the air layer with outside air. The bonded optical element according to claim 1, wherein the contact portion is formed on a rough surface having a fine uneven portion. Applying an energy curable resin on the optical surface of the first optical substrate having a contact portion outside the effective optical diameter;
Stretching the energy curable resin with a second optical substrate having a contact portion outside the effective optical diameter;
Contacting the contact part of the first optical substrate with the contact part of the second optical substrate so as to leave an air layer on the outer periphery of the energy curable resin;
And a step of curing the energy curable resin by irradiating energy. A method for producing a bonded optical element, comprising: In the step of applying the energy curable resin, a necessary amount of energy curable resin is applied so that an outer periphery of the energy curable resin when the contact portion is brought into contact is between the optical effective diameter and the contact portion. It applies. The manufacturing method of the joining optical element of Claim 6 characterized by the above-mentioned.

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