JPH0565325B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a wrench that can easily manufacture a mold for molding a lenticular lens sheet with high precision, which is used when manufacturing a lenticular lens sheet one by one by a pressing method or the like. The present invention relates to a method for manufacturing a mold for molding a cyular lens sheet.

A lenticular lens is a lens shaped like the side surface of a cylinder. For example, a lenticular lens sheet in which lenticular lenses are arranged side by side refracts parallel light rays in one direction (e.g., vertical direction) and condenses them. It is something that works.

In recent years, by taking advantage of the effects of lenticular lens sheets and appropriately combining them with other lenses, they are often used in projection-type television screens that project images from the back and are viewed from the front. This is because it is difficult to make large cathode ray tubes for televisions due to manufacturing constraints, and from a macroscopic perspective, technology is needed to give the screen the required performance by changing the microscopic shape of the plastic sheet on the flat plate. This is because they have improved.

By the way, when manufacturing such lenticular lens sheets continuously by melt extrusion method etc., it is normal to use a roll-shaped mold for shaping. could be manufactured relatively easily by using a lathe etc. and devising a cutting tool. However, in order to manufacture lenticular lens sheets one by one, a roll mold cannot be used, and a flat mold must be used.
By using a flat mold, lenticular lens sheets of various shapes can be manufactured by changing the mold.
This method is more suitable for producing a wide variety of products than the melt extrusion method using a roll mold.

However, although plate-shaped molds can be manufactured using a cutting machine that can cut flat plates, the dimensions that can be cut by the cutting machine are limited, and there is no advantage of using a general-purpose lathe. The present invention solves the above-mentioned drawbacks of the prior art.The present invention solves the above-mentioned drawbacks of the prior art.The present invention is directed to forming a convex lens and a concave lens by rotating a cylinder in which a cut material layer is provided by plating on the side surface of a cylindrical base body through a release layer. A lenticular device characterized in that an inverted shape is formed by cutting so that each lens is connected at a tangent to each lens, and convex lenses and concave lenses are arranged alternately, and then the cut material layer that has already been cut is peeled off. The present invention relates to a method of manufacturing a mold for molding a lens sheet. In this case, the release layer may be a silver-plated layer, and the cutting material layer may be a copper-plated layer.

Hereinafter, the manufacturing method of the present invention will be explained in detail with reference to the drawings.

First, as shown in FIG.
A peelable cutting material layer 2 is provided on the side surface of the cutting material. A typical example is copper ballad plating when producing a gravure printing plate, where the copper plating layer becomes the cutting material layer 2. The cutting material layer 2 may be made of a metal other than copper; in the case of copper, an iron cylinder is plated with silver to form a release layer, and a copper plating layer is provided on the release layer. Even in the case of other metals, the cutting material layer can be peeled off via an appropriate peeling layer. In addition, synthetic resins can also be used as the material for the cutting material layer.

Next, by cutting the surface of the cutting material layer 2 while rotating the cylinder 3, reverse shapes of convex lenses and concave lenses are provided so as to be arranged alternately.

Figure 2 schematically shows the state of cutting, in which the cutting tool 4 of the desired shape is cut while rotating the cylinder 3.
This is an example of cutting in a spiral shape by feeding the material in the direction of the arrow (from the left side to the right side in the drawing).

In addition to the shape of the cutting tool shown by 4 in Figure 2,
It is also possible to use a shape as shown in FIG. 3a or a combination of two as shown in FIG. 3b.

Regardless of the shape of the cutting tool used, when cutting while feeding the cutting tool, in order for the protrusions and recesses on the mold surface to connect smoothly, the protrusions on the mold and the adjacent recesses must be placed at a position where their tangent lines coincide. It is necessary that they are connected so that they can be spliced together. By doing this, the refraction of light will change continuously in each part of the lens sheet, and the joints between the cut parts will be smooth and continuous.

After cutting, the cutting material layer on the cylinder surface is peeled off, and then the peeled off cutting material layer is preferably pressed to flatten it.

FIG. 4 shows an example of the pressing method, in which the peeled cutting material layer 2' is flattened by passing it through a three-roll combination of rolls 5, 6 and 7. Since the convex part of the cutting material layer 2' is a mold for a concave lenticular lens, the top part of the convex part has a relatively smooth curved surface, and the pressure applied to the level of flattening is virtually impossible. , the top of the convex portion will not collapse. For reference, if a cut material layer that has been cut into a shape as shown in FIG. 5 is similarly pressed, the convex portions will be crushed, which is not preferable.

The mold obtained as described above can be used as a mold for pressing, casting of synthetic resin, etc., and can be used in combination with molds of other shapes to manufacture various lens sheets.

According to the method of the present invention, a mold for molding a lenticular lens sheet can be easily created using a lathe,
By changing the cutting tool, it is possible to create molds for lenticular lens sheets having various pitches and refractive performances.

[Brief explanation of the drawing]

Figures 1, 2, and 4 are explanatory diagrams showing the manufacturing method of the present invention, Figure 3 is an explanatory diagram showing another example of the cutting tool used, and Figure 5 is a reference diagram. . 1... Cylindrical base, 2... Cutting material layer,
3...Cylinder, 4...Bite, 5-7...Roll.

Claims (1)

[Claims] 1. While rotating a cylinder in which a cutting material layer is provided on the side surface of a cylindrical base by plating through a release layer, each lens is formed into an inverse shape of a convex lens and a concave lens. A method for producing a mold for molding a lenticular lens sheet, characterized in that the mold is formed by cutting so that convex lenses and concave lenses are connected on tangent lines and are arranged alternately, and then the cut material layer that has already been cut is peeled off. 2. Manufacturing a mold for molding a lenticular lens sheet according to claim 1, wherein the peeling layer is a silver plating layer, and the cutting material layer is a copper plating layer. Law.