JP3004262U - Polarized lens for sunglasses - Google Patents

Abstract

(57) [Summary] [Purpose] To increase the impact strength of polarized lenses for sunglasses,
It is to improve safety for users. [Structure] A spherical transparent acrylic lens 3 is attached to the outer surface of the spherical polarizing film 2, and a spherical transparent polycarbonate lens 4 is attached to the inner surface of the polarizing film 2 for sunglasses. The polarizing lens 1 is configured.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improved polarized lens for sunglasses.

[0002]

[Prior art]

 A polarized lens is often used as a lens for sunglasses. This type of conventional polarizing lens is a so-called cemented lens, and glass or highly transparent plastic lenses are cemented as lens elements on both sides of the polarizing film. For this reason, when a strong impact is applied to the polarized lens from the outside, the polarized lens is easily broken, and the debris of the lens element at the time of breaking easily causes an accident such as damage to the eyes and face of the user. Under such circumstances, sunglasses lenses are required to have high safety.

[0003]

[The purpose of the device]

 Therefore, an object of the present invention is to increase the impact strength of this type of polarized lens for sunglasses and enhance the safety for the user.

[0004]

[Solution of the device]

 Based on the above-mentioned object, the present invention attaches a spherical transparent acrylic lens to the outer surface of a spherical polarizing film, and a spherical transparent polycarbonate lens to the inner surface of the polarizing film. It constitutes a polarized lens for sunglasses.

[0005]

【Example】

 FIG. 1 shows a polarized lens 1 for sunglasses of the present invention, and FIG. 2 shows an enlarged cross section thereof. The polarized lens 1 for sunglasses of the present invention comprises a spherical transparent acrylic lens 3 and a polycarbonate lens 4 each having a curvature similar to that of the polarizing film 2 on the outer surface and the inner surface of the spherical polarizing film 2 and a transparent adhesive 5 respectively. It is configured by pasting together.

The polarizing film 2 is, for example, a thin film of polyvinyl alcohol, and is polarized by a polarization process. That is, the thin film of polyvinyl alcohol is dipped in the iodine solution while being stretched. At this time, the iodine solution is a mixed solution of dichroic iodine and an alcohol solution, and the thin film of polyvinyl alcohol is dipped in the mixed solution while being stretched, and the process proceeds to the drying step. . In this process, tension is applied to the polyvinyl alcohol thin film, so that the chain molecules are in a parallel state and iodine is uniformly attached to the thin film. Iodine crystals are adsorbed on the thin film chain molecules in a regular array, and impart dichroism, that is, polarizability. After drying, the polarizing film 2 is molded into a spherical surface with appropriate curvature for sunglasses while applying appropriate heat. When the polarizing lens 1 is colored, it is advantageous to color it by immersing it in a coloring dye in the polarization processing step of the polarizing film 2.

The acrylic lens 3 is formed in a spherical shape by a transparent acrylic resin on the inside with a curvature substantially the same as that of the polarizing film 2. Acrylic resin is mechanically tough, is thermally stable after molding, and is not easily deformed, but has the possibility of dispersion fracture due to strong external impact. When it is necessary to correct the visual acuity, the acrylic lens 3 having a high refractive index is formed as a meniscus concave lens or a meniscus convex lens. The polycarbonate lens 4 is made of a polycarbonate resin and is formed into a spherical surface with a curvature attached to the inner surface of the polarizing film 2.

The acrylic lens 3 is attached to the outer surface of the spherical polarizing film 2, that is, the surface on the object side with an adhesive 5, and the polycarbonate lens 4 is inside the polarizing film 2, that is, on the eyepiece side. The surface is attached with an adhesive 5. In the process of bonding these, the adhesive 5 is applied to the acrylic lens 3 and the polycarbonate lens 4 substantially at the center of the bonding surface side. When the acrylic lens 3 and the polycarbonate lens 4 sandwich the polarizing film 2 and are pressed in the bonding direction, the adhesive 5 spreads from the center of the polarizing film 2 toward the outer peripheral edge, Even without air bubbles, it diffuses evenly on the bonding surfaces and fixes them together.

Here, the polycarbonate resin is tough, stable to heat and light, and has excellent impact strength. Therefore, even if a strong impact is applied from the outside, the polycarbonate resin does not break into fine fragments and does not cause any sharp cracks. Do not disperse and destroy. Therefore, when a strong impact is applied to the polarized lens 1 for sunglasses, the eyepiece side of the polycarbonate lens 4, that is, the polarized lens 1, that is, the part of the wearer's eyes does not disperse and break, so that the wearer is protected from damage by debris. Will be protected. If the polarizing film 2 is colored, even if interference occurs between the polarizing film 2 and the polycarbonate lens 4 due to the optical path difference, the interference fringes are visible from the outside, that is, from the objective side of the acrylic lens 3. Since it disappears, the effect of interference fringes can be suppressed to a low level.

[0010]

[Effect of device]

 The present invention provides the following unique effects. A polycarbonate lens is attached to the eyepiece side of the polarized lens for sunglasses, and it does not disperse and break due to a strong external impact, so eye damage due to debris can be prevented in advance. In addition, since a mechanically stable and strong acrylic lens is attached to the outer surface of the polarizing film, a polarizing lens that is stable against heat and external force and has no distortion even when framed is obtained.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view of a polarized lens for sunglasses according to the present invention.

FIG. 2 is an enlarged sectional view of a part of the polarized lens for sunglasses of the present invention.

[Explanation of symbols]

 1 Polarized lens for sunglasses 2 Polarized film 3 Acrylic lens 4 Polycarbonate lens 5 Adhesive

Claims (1)

[Scope of utility model registration request] 1. A spherical transparent acrylic lens (3) is attached to the outer surface of a spherical polarizing film (2), and a spherical transparent polycarbonate lens (is attached to the inner surface of the polarizing film (2). 4) A polarized lens for sunglasses (1), which is obtained by bonding together 4).