JPS6344204B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lens having a bonding function and configured to bond two or more lenses to each other, such as a bonded lens used in a lens system consisting of a plurality of lenses. It is something.

As is well known, in a lens system consisting of a plurality of lenses, a lens in which two or more lenses are cemented together is used. In such a cemented lens, for example, as shown in FIG. 1 (FIG. 1 shows an example of cementing two lenses), one first lens 1 is a concave lens, and the other second lens 2 is a convex lens. At the same time, mutual joint surfaces 1a and 2a
By forming them with the same radius of curvature, the joint surfaces 1a and 2a are configured to be joined in a close fit manner. Then, the joint surfaces 1a of the first and second lenses 1 and 2 formed as described above,
By interposing an adhesive (adhesive layer) 3 to 2a and pressing both lenses 1 and 2 in the optical axis direction, the lenses 1 and 2 are bonded together.

However, in the conventional configuration and bonding means as described above, no particular problem occurs when the cemented lenses 1 and 2 are glass lenses.
When both lenses 1 and 2 are made of plastic lenses, or when one of both lenses 1 and 2 is made of plastic lenses, the following problems occur.

That is, first of all, if both lenses 1 and 2 are plastic lenses, the mutual cementing surfaces 1a,
Depending on the properties of the adhesive 3 interposed between the lenses 2a and 2a, the bonding surfaces 1a and 2a may be eroded by the adhesive 3, and the bonding surfaces 1a and 2a may be roughened, causing the first and second lenses 1, Performance (function) of both lenses
A situation had arisen in which it was impossible to maintain the Also,
Even when the bonding surfaces 1a and 2a are bonded using the adhesive 3 which does not corrode them, the following problems occur. That is, when bonding two plastic lenses 1 and 2 together with the adhesive 3, it is necessary to press each lens 1 and 2 in the direction of the optical axis. A situation has arisen in which the shape of the lens 1 is deformed due to the pressing force so that the radius of the curve changes, and the adhesive 3 is solidified and bonded in the deformed state.
In this case as well, the curvature of the first lens 1 changes, resulting in the inability to obtain desired lens performance. In addition, variations in the adhesive layer occur due to changes in the shape of the first lens 1, and as a result, the adhesive 3 does not harden uniformly, resulting in a large asperity in the bonded lens system, and due to lens aberrations. There were also problems. Furthermore, even if the lens system bonded together via the adhesive 3 is normal, if a relatively large temperature change or humidity change is applied to the lens system, the adhesive layer 3 will change due to the shape change of each lens 1, 2. There was a problem in that the lenses peeled off and the lens performance as a bonded lens system could not be maintained.

Second, even when one of the lenses 1 and 2 is a plastic lens and the other side is a glass lens, there are the following problems similar to the case where both lenses are plastic lenses. That is, when an attempt is made to bond a glass lens 1 and a plastic lens 2 together via an adhesive 3, the adhesive 3 begins to shrink as it solidifies, and due to this shrinkage, the bonding surface 2a on the plastic lens 2 side A phenomenon occurs in which the surface shape changes significantly (changes in the radius of curvature and waviness and wrinkles appear on the joint surface).
Therefore, a laminated lens having desired lens performance could not be obtained. Furthermore, even if the changes in the bonding surface 2a during bonding are small, if the bonded lenses 1 and 2 are used under conditions where relatively large changes in temperature or humidity occur, these changes will cause the adhesive 3 to may peel off, or the surface shape of the adhesive 2a on the plastic lens 2 side may change significantly (this may be more than 10 times the amount of bonding), making it impossible to maintain the lens performance when bonded. There was a problem. Furthermore, depending on the properties of the adhesive 3, the joint surface 2a on the plastic lens 2 side may be eroded, and in this case as well, the desired lens performance cannot be obtained, which has been a problem.

The present invention was made in view of the problems in the prior art described above, and it is possible to configure a plurality of lenses so that they can be bonded together without intervening an adhesive in the lens body, and to ensure that the desired lens performance is achieved. By configuring it so that it can be retained, the various problems in the prior art described above are solved. Hereinafter, embodiments of the present invention will be described in detail using the drawings from FIG. 3 onwards.

Figures 3a and 3b show a side cross section of a lens having a bonding function according to the present invention. A lens 5 is shown, respectively. The inner surface 6a of the lens body 6 of the first lens 4 is formed to have the same radius of curvature as the outer surface 7a of the lens body 7 of the second lens 5, and both lenses 4 and 5 are arranged interchangeably as shown in FIG. When joined to each other, the inner surface 6a and outer surface 7a of each other
are configured to be joined in a tight fit.

A flange-shaped first lens support portion 6b is integrally provided on the outer peripheral portion of the lens body portion 6 of the first lens 4, and the inner surface portion 6c of this first lens support portion 6b has an appropriate depth. The recesses 8 are equally distributed in the circumferential direction (as long as the distribution is not biased, the distribution is not limited to equal distribution).

A flange-shaped second lens support part 7b similar to the first lens support part 6b is integrally provided on the outer peripheral part of the lens body part 7 of the second lens 5, and this second lens support part 7b A protrusion 9 that can be freely engaged with and detached from the recess 8 of the first lens 4 is integrally provided on the outer surface 7c of the lens. This protrusion 9
is elongated with a small diameter, and is designed to have elasticity. As shown in FIGS. 3b and 4, the outer surface portion 7c of the second lens support portion 7b is larger than the contact surface 7d of the second lens body portion 7 with the inner surface portion 6c of the first lens body portion 6. Therefore, as shown in FIG. 4, both lenses 4 and
5 is bonded, the outer surface portion 7c of the second lens 5
and the inner surface 6c of the first lens 4.
is beginning to form. Further, when both lenses 4 and 5 are joined so that the contact surfaces 7d and inner surfaces 6c are in contact with each other, the protrusion 9 is configured to be engaged with the recess 8, and therefore, A so-called play part 9a is formed in the protrusion 9 by the gap width H. The contact surface 7d is
As shown in FIG. 5, they may be provided on the entire circumferential surface of the second lens main body 7, or as shown in FIG. As long as the distribution is not biased, the structure is not limited to equal distribution). Furthermore, it is also possible to eliminate the contact surface 7d. In short, the contact surface 7d may have any configuration as long as it can position the first lens 4 and the second lens 5 when they are bonded together. Further, the shape of the protrusion 9 is not limited to a circular cross section as shown in FIGS. 5 and 6, but may be long in the circumferential direction as shown in FIG. 7, for example. Alternatively, the eighth
As shown in the figure, it may be formed to be long in the radial direction (radial direction), and may be arranged in a so-called radial manner. In short, the shape and number of projections 9 are not limited as long as the first lens 4 and second lens 5 can be reliably joined together.

The first lens 4 and the second lens 5 having the above configuration
This means that when they are joined together as shown in FIG. 4, they will not separate from each other through the adhesive (adhesive layer) 11 interposed between the protrusion 9 and the recess 8. It is configured to be fixedly joined.

In the above configuration, the operation and effects of the present invention will be explained. That is, according to the above configuration, the inner surface 6c of the lens support portion 6b in the first lens 4
Since a gap H is maintained between the lens support portion 7b and the outer surface portion 7c of the lens support portion 7b of the second lens 5 when the lenses 4 and 5 are bonded to each other, bonding pressure in the thrust direction (optical axis direction) is applied during bonding. Even if this gap width H
can absorb shape deformation in the thrust direction. Therefore, the bonding surfaces 6a, 7a of the lens bodies 6, 7 are not deformed by the bonding pressure during bonding, and the desired lens performance can always be maintained. Also, the temperature or humidity may change due to changes in usage conditions, and the lens body 6,
Even if the lens body parts 7 expand or contract in the radial direction, the deformation in the radial direction is absorbed by the action of the gap 10 and the protrusion part 9, so that the lens body parts 6, 7
No excessive force is applied to the Therefore,
Also in this case, the joint surface 6 of the lens body parts 6 and 7
a, 7a are not deformed, and the desired lens performance can always be maintained. Further, the present invention also provides a bonding surface 6a of the lens body portions 6 and 7,
Both lenses 4, without interposing adhesive to 7a.
5, so that there is no deformation of the bonding surface when the adhesive hardens or roughening of the bonding surface due to erosion by the adhesive, unlike in the prior art. Therefore, lenses 4, 5 according to the invention
According to the above, even if both lenses 4 and 5 are made of plastic lenses, or even if they are a cemented lens in which one is a plastic lens and the other is a glass lens, the desired lens performance can always be achieved. It is something that can be kept.

What is shown in FIG. 9 is a second embodiment of the present invention, in which a groove 12 is formed at the root portion of the protrusion 9, and the root portion of the protrusion 9 is formed into a small diameter portion. This is what I did. Note that the other configurations are the same as those shown in FIGS. 3 to 8, and will therefore be omitted.

According to the above configuration, even if the first lens 4 or the second lens 5 is deformed in the radial direction due to temperature change or humidity change, the protrusion 9 is easily deformed and the lenses 4 and 5 expand and contract. Since deformation can be absorbed, it is possible to prevent large shape changes, bond separation, stress, distortion, etc. that would occur in the lenses 4 and 5 during deformation, which is extremely convenient. Note that the other functions and effects are the same as those in the first embodiment, so their explanations will be omitted.

FIG. 10 shows a third embodiment of the present invention, in which a concave groove 13 is formed around the root of the protrusion 9 in the lens support 7b of the second lens 5. It is something. Note that the other configurations are the same as those shown in FIGS. 3 to 8, and will therefore be omitted.

According to the above configuration, similarly to the second embodiment shown in FIG. can absorb expansion and contraction deformation.
As a result, it is possible to prevent the occurrence of large shape changes, bond separation, stress, distortion, etc. that would occur when the lenses 4 and 5 are deformed, and the lens performance can be maintained normally. Regarding other actions and effects,
Since this is the same as the first embodiment, its explanation will be omitted.

What is shown in FIG. 11 is a fourth embodiment of the present invention, in which an engaging recess 8 and an engaging protrusion 9 are provided on each of the first lens 4 and the second lens 5.
It is configured by providing each of them.

The operations and effects of the above configuration are the same as those of the first embodiment, so their explanations will be omitted. Also, in the above configuration, FIG.
Of course, the configuration shown in FIG. 10 can be applied.

In addition to the above embodiments, the lens bodies 6, 7, recesses 8, protrusions 9, play areas 9 in each lens 4, 5
Of course, by configuring a with members made of different materials, it is possible to more effectively absorb changes in shape when the lenses 4 and 5 are deformed. In particular, in the case of a plastic lens, it can be double molded, and in the case of a glass lens, it can be outsert around the glass lens.

Further, in the above embodiment, an example was shown in which two lenses 4 and 5 are bonded to each other, but this is not limited to bonding two lenses, and in the case of bonding two or more lenses. It can also be applied to

As described above, the present invention allows the lens bodies of a plurality of lenses to be bonded to each other to be fixedly bonded to each other without intervening any adhesive, and also absorbs shape deformation of the lenses. Since the lens is constructed with a cavity for the purpose of the lens, even if each lens expands or contracts due to changes in temperature or humidity, the shape deformation can be easily absorbed. Therefore, even if the temperature and humidity change depending on the surrounding conditions in which the cemented lens is used, the specified lens performance can always be maintained.
The quality of the cemented lens can always be guaranteed stably.

[Brief explanation of drawings]

Figures 1a and b are side sectional views showing a cemented lens with a conventional configuration, and Figure 2 is a side sectional view showing its bonded state.
FIGS. 3a and 3b are side sectional views of a lens having a bonding function according to the present invention, FIG. 4 is a partially enlarged sectional view showing the lenses of FIGS. 3a and b in a bonded state, and
6, 7, and 8 are plan views showing embodiments of essential parts of the present invention, FIG. 9 is a partially enlarged side view showing a second embodiment of the invention, and FIG. 10. 1 is a partially enlarged side view showing a third embodiment of the present invention;
FIG. 1 is a side sectional view showing a fourth embodiment of the present invention. 4...First lens, 5...Second lens, 6,7
. . . Lens main body, 8 . . . Engagement recess, 9 . . . Engagement protrusion, 10 . . .

Claims (1)

[Scope of Claims] 1. In a plurality of lenses configured such that the cemented surfaces of the respective lens bodies are formed to have the same radius of curvature so that they can be freely joined, each of the lenses has a flange-like lens on the outer periphery of each of the lens bodies. A lens in which a supporting portion is integrally formed and a plurality of recesses or protrusions that can be freely engaged with each other are provided in each of the lens supporting portions, and the respective lens supporting portions are brought into contact with each other and the engaging recess is formed. A stepped portion is provided on at least one of the support portion and the lens support portion forming the engagement protrusion to form a gap around the engagement protrusion, and between the engagement recess and the engagement protrusion. By fixedly joining the lenses to each other through an adhesive interposed between the lenses and imparting elasticity to the engaging protrusion, the shape deformation in the thrust direction when the lenses are joined and during use are prevented. A lens having a bonding function, characterized in that it is configured to absorb shape deformation in the radial direction.