JP2000326418A - Production of resin bonding type lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a method for producing a resin bonding type lens wherein when a glass lens coated with a resin liq. is turned reversely and is fed into a mold, there exists no possibility of sagging down of the resin liq. and time for a process wherein the resin liq. is filled into a specified shape is shortened and there exists no possibility of generating fine bubbles. SOLUTION: After a specified amt. of resin liq. 2 is fallen down on the surface of a glass lens 1 and before the above described lens is arranged in such a way that the face coated with the resin liq. of the glass lens 1 is faced to the mold face of a mold 14b, a process wherein gas is jetted from the central part of a chuck 11 to spread the resin liq. 2 and a recessed part is formed at the central part of the resin liq. 2, is added.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a resin-bonded lens in which a resin layer having a desired surface shape is formed on the surface of a spherical lens as a base material.

[0002]

2. Description of the Related Art Conventionally, in order to manufacture an aspherical lens using glass as a material, high-precision grinding and polishing are required, and a long processing time is required, resulting in poor production efficiency and not suitable for mass production. There was a problem. As another manufacturing method, a direct press method of hot-pressing a glass material using a mold heated to a high temperature is known. In this method, although high-precision processing can be performed, a glass material to be applied is used. However, there is a problem that the diameter that can be processed is limited to a small one, and the cost is high because the apparatus is expensive. On the other hand, resin lenses can be manufactured in large quantities by using injection molding, etc., so the cost per lens can be reduced, but they are more susceptible to temperature and humidity, and compared to glass. Therefore, there is a problem that optical performance fluctuates.

Therefore, in order to make up for the disadvantages of both the glass material lens and the resin material lens and to solve the above problems,
A resin-bonded lens in which a resin layer having an aspheric shape is bonded to a surface of a spherical glass lens serving as a base material has been developed, and is widely used in video equipment. A method for manufacturing such a resin-bonded lens is disclosed in JP-A-8-244128. FIG. 5 is a sectional view showing the manufacturing method. First, as shown in FIG. 5A, the spherical glass lens 1 is placed so that the main plane is horizontal, and a predetermined amount of an ultraviolet-curable resin liquid 22 is applied drop-wise to the center of the surface.
Next, as shown in FIG. 5B, the spherical glass lens 1 is
The mold 2 is inverted in the vertical direction from the state of FIG.
3 and is placed on the upper surface of the seal mold 25 by the positioning mechanism 26 so as to be supported in the contact area.
Then, as shown in FIG.
The sealing liquid 25 is pushed down so that the resin liquid 22 applied on the surface of the glass 1 has a predetermined thickness from the surface of the glass 1 to fill the resin liquid 22 into the metal mold. After that, the resin liquid 22 is cured by irradiating ultraviolet rays by ultraviolet irradiating means 24, and after curing, the resin molding layer is peeled off from the interface with the mold 23 to obtain a desired resin-bonded lens.

[0004]

However, in the above-described conventional manufacturing method, when the glass lens 1 coated with the resin liquid 22 is turned over and supplied to the seal mold 25, the viscosity of the resin liquid 22 is increased. Has a problem that the liquid drips down due to its own weight. In addition, the resin liquid 22
Even if the liquid does not droop, it hangs down in an icicle-like manner, so that it takes time in the step of filling the resin liquid 22, and there is also a problem that fine bubbles are involved and defects occur frequently.

Accordingly, the present invention provides a method of manufacturing a resin-bonded lens in which the resin liquid 22 does not droop, the time for the step of filling into a predetermined shape is reduced, and fine bubbles are not generated. The purpose is to do.

[0006]

In order to solve the above problems and achieve the object, according to the first aspect of the present invention, a predetermined amount of a resin liquid is dropped on a lens surface, and the resin liquid application surface of the lens is molded in a mold. The lens is disposed so as to face a surface, and the mold and the lens surface are relatively moved so that the space between the mold surface and the lens surface is a design value, and the resin liquid is molded. After filling the inside, the resin liquid is cured, and the cured resin molding layer is separated from an interface with a mold. In the method for manufacturing a resin-bonded lens, a predetermined amount of the resin liquid is dropped on the lens surface. After that, before disposing the lens so that the resin liquid application surface of the lens faces the mold surface, a step of spreading the resin liquid in advance is added.

According to a second aspect of the present invention, in the method for manufacturing a resin-bonded lens according to the first aspect, a fluid pressure is used for the means for spreading the resin liquid. According to a third aspect of the present invention, in the method for manufacturing a resin bonded lens according to the second aspect, the fluid is air.

According to a fourth aspect of the present invention, in the method for manufacturing a resin-bonded lens according to the second aspect, the fluid is an inert gas.

[0009]

In the present invention, since the resin liquid applied to the lens surface is spread out before the lens inversion, the resin liquid hardly sags even if it flows due to its viscosity in a short time after the lens inversion. Even if it hangs down, the shape of the resin liquid is not an icicle shape but a bell shape, so that it does not take a long time to fill the mold in the next step, and no fine bubbles are involved. (Claim 1) Further, it can be easily implemented by using the pressure of a fluid as the means for spreading, particularly air as the fluid. (Claims 2 and 3) In the case where the resin liquid applied to the lens surface is anaerobic, the use of an inert gas can be carried out without causing a curing failure. (Claim 4)

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. The method for producing a resin-bonded lens according to the present invention includes a first step of dropping a resin liquid on a surface of a glass lens as a base material, a second step of previously spreading the resin liquid that has been dropped and applied, A third step of installing the lens on the mold such that the resin liquid application surface of the lens faces the mold surface, and a space between the mold surface and the lens surface is designed to be a designed value. A fourth step of relatively moving the lens and the mold to fill the mold with the resin liquid applied to the glass lens on the mold, and a fifth step of curing the filled resin liquid. And a sixth step of separating the resin molding layer from the interface with the mold.

The mold used in the embodiment of the present invention is composed of a seal mold and a molding mold, and an ultraviolet curable resin is used as a resin applied to the lens surface. less than,
The respective steps will be described with reference to the drawings. FIG. 2 shows a spherical glass lens (hereinafter referred to as a lens) 1 with a resin liquid 2
FIG. 5 is a partial side view (partially sectional view) showing a first step of dropping a droplet. First, the lens 1 as a base material is placed on the receiving base 31, and the space formed by the receiving base 31 is set to a negative pressure, whereby the lens 1 is held. The receiving table 31 is installed on a moving member (not shown), and can be arranged directly below the discharge section 32 of the resin liquid application device by moving the moving member. The discharge part 32 can be moved up and down by a pneumatic cylinder 33 and a linear guide 34, and drops the resin liquid 2 in a state where the resin liquid 2 is lowered to the vicinity of the lens 1. At this point, the resin liquid 2 has a small mountain shape at the center of the lens 1 although it depends on the viscosity of the resin liquid 2. After the end of the dropping, the discharge unit 32 is raised, and the lens 1 is offset from the application position of the resin liquid application device by the moving member together with the cradle 31 to complete the first process.

FIG. 1A is a partial side view (partially sectional view) showing a second step of expanding the resin liquid 2 dropped on the lens 1. First, the reversing chuck 11 descends and comes into contact with the outer periphery of the lens 1. In this state, the chuck 11
A gas that pushes and spreads the hill-shaped resin liquid 2 is blown out from the central portion. The resin liquid 2 is applied to the lens 1 by gas pressure.
It spreads along the surface shape, and a depression is formed at the center as shown in the figure.

Next, a third step of arranging the lens 1 in the mold 14 so that the surface of the lens 1 coated with the resin droplet faces the mold surface of the molding die 14b will be described. First, FIG.
In this state, the negative pressure in the space between the lens 1 and the cradle 31 is released to release the lens 1 from the cradle 31. Further, a space defined by the reversing chuck 11 and the lens 1 is provided in a flow path different from the gas blowing hole in the second step.
A negative pressure is applied to the lens 1 (not shown) to hold the lens 1 on the reversing chuck 11. Then, the reversing chuck 11 is moved up, and is turned 180 degrees by the rotary actuator 12 in the vertical direction.
The lens 1 is inverted to a state where the lens 1 is at a position drawn by a two-dot chain line in FIG. The chuck 11 in an inverted state
, The forming chuck 13 descends and contacts the lens 1 to release the negative pressure in the space between the reversing chuck 11 and the lens 1. On the other hand, by making the space formed by the forming chuck 13 and the lens 1 a negative pressure,
Is released from the reversing chuck 11 and the forming chuck 13
Is held in the state. In this state, the forming chuck 13
Rises and is moved directly above the mold 14 by a moving member (not shown), and the molding chuck 13 is lowered while holding the lens 1 to bring the lens 1 into contact with the upper surface of the seal mold 14a. The forming chuck 13 is a gimbal mechanism (not shown).
The lens 1 is uniformly supplied on the seal mold 14a, and is supplied to the mold so that the application surface of the lens 1 faces the mold surface of the molding mold 14b as shown in FIG. 1C. You.

Next, the space between the mold surface of the molding die 14b and the surface of the lens 1 is set to a design value.
And the mold 14b are relatively moved to fill the mold with the resin liquid applied to the glass lens on the mold.
Step will be described. FIG. 3 is a cross-sectional view showing a state where the resin liquid 2 on the surface of the lens 1 is filled in a predetermined shape. The lens 1 is aligned with the mold 14 by the alignment mechanism 15 while being held by the molding chuck 13.
The forming chuck 13 also has an alignment mechanism (not shown), and is aligned with the lens 1. After the alignment is completed, the sealing die 14a together with the forming chuck 13 holding the lens 1 is lowered to a predetermined position. At this time, the resin liquid 2 applied to the surface of the glass lens 1 is filled in the mold by the molding die 14b having a desired surface shape on the die surface. After a certain period of time has elapsed in this state, the negative pressure between the forming chuck 13 and the lens 1 is released, the forming chuck 13 opens the lens 1, and moves to the reversing chuck side by the moving member (not shown).

Next, the fifth step of curing the filled resin liquid will be described with reference to FIG. FIG. 4 is a cross-sectional view showing a step of irradiating the filled resin liquid 2 with ultraviolet rays to cure the resin liquid 2. The ultraviolet irradiation means 51 is moved onto the mold 14b by a moving member (not shown), and is lowered until the mask 52 of the irradiation means 51 comes into contact with the lens 1. The opening diameter of the mask portion 52 does not match the diameter of the desired region. If the resin liquid 2 is irradiated with ultraviolet rays in a state where the area outside the lens 1 is masked, even if the resin liquid in the area hardens and contracts, the decrease in the volume of the resin due to the contraction is caused by the uncured resin liquid outside the area. Is supplied. Resin liquid 2
Since the diameter of the luminous flux of the ultraviolet light to be irradiated is affected by the curvature and the refractive index of the lens 1, the opening diameter of the mask portion 52 is set in consideration of these factors. After the irradiation of the ultraviolet rays in the desired area is completed, the mask portion 52 is removed, and the entire surface of the resin liquid 2 is again irradiated with the ultraviolet rays.

After the resin liquid 2 has hardened, a release part (not shown)
As a result, a sixth step of separating the resin molding layer from the interface with the mold 14 is performed. The material of the ultraviolet-curable resin liquid used in the present invention can be appropriately selected from epoxy resins, unsaturated polyester resins, urethane resins, urethane acrylate resins, modified acrylic resins, and the like.
In addition, the resin is not limited to the ultraviolet curable resin,
There is no problem even if a thermosetting resin is used. In addition, not only ultraviolet rays but also electron beams, γ rays, α rays and the like may be used as energy rays.

[0017]

As described above, according to the present invention, since the resin liquid applied to the lens surface is spread beforehand before inversion of the lens, the resin liquid does not drip and the yield rate is improved. Also, since the shape of the resin liquid that hangs down from the lens surface is improved, the time required for the step of filling the resin liquid into a predetermined shape is shortened, and the yield rate is improved because fine bubbles are not involved when filling the mold. There is also an effect.

[Brief description of the drawings]

FIG. 1 is a partial side view showing a step of supplying a glass lens having a resin liquid on its surface to a mold in a method of manufacturing a resin-bonded lens according to the present invention.

FIG. 2 is a partial side view showing a step of dropping and applying a resin liquid to a glass lens surface in the method of manufacturing a resin-bonded lens according to the present invention.

FIG. 3 is a cross-sectional view showing a state in which a resin liquid on a lens surface is filled into a predetermined shape in a method for manufacturing a resin-joint lens according to the present invention.

FIG. 4 is a cross-sectional view illustrating a step of irradiating a filled resin liquid 2 with ultraviolet rays to cure the resin liquid 2 in the method of manufacturing a resin-bonded lens according to the present invention.

FIG. 5 is a process chart showing a conventional method for manufacturing a resin-joined lens.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Glass lens 2, 22 ... Resin liquid 11 ... Reversing chuck 12 ... Rotary actuator 13 ... Molding chuck 14 ... Die 14a, 25 ... Seal type 14b, 23. ..Molds 24,51 ... Ultraviolet irradiation means 15,26 ... Positioning mechanism 31 ... Receiving table 32 ... Discharge unit 33 ... Pneumatic cylinder 34 ... Straight guide 52 ... Mask part

Claims (4)

[Claims] 1. A predetermined amount of a resin liquid is dropped on a lens surface, and the lens is disposed so that a resin liquid application surface of the lens faces a mold surface. After moving the mold and the lens surface relative to each other so that the space becomes a design value, filling the mold with the resin liquid, curing the resin liquid, and setting the cured resin molding layer to the mold. In a method for manufacturing a resin-bonded lens, comprising a step of peeling off from an interface, a predetermined amount of a resin liquid is dropped on a lens surface, and then the lens is supplied so that a resin liquid application surface of the lens faces a mold surface. A method of manufacturing a resin-joint type lens, wherein a step of spreading the resin liquid is added before performing the method. 2. The method for manufacturing a resin-bonded lens according to claim 1, wherein a fluid pressure is used as a means for spreading the resin liquid. 3. The method for manufacturing a resin-bonded lens according to claim 2, wherein the fluid is air. 4. The method for manufacturing a resin-bonded lens according to claim 2, wherein the fluid is an inert gas.