Patent ID: 12197048

DESCRIPTION OF EMBODIMENTS

The following describes embodiments of the present invention with reference to the accompanying drawings. Note that elements that are the same or equivalent are indicated by the same reference signs in the drawings and description thereof is not repeated. Furthermore, hatching for indicating a section is omitted as appropriate for the sake of simplicity of the drawings. In the embodiments, an X axis, a Y axis, and a Z axis of a three-dimensional Cartesian coordinate system are indicated as appropriate for facilitating understanding of the drawings. The direction of the Y axis is an example of a left-right direction in the field of view of a wearer of an eyeglass lens1of the present invention. The left-right direction in the field of view of the wearer is a direction from the left eye toward the right eye of the wearer, for example. In the following, the left-right direction in the field of view of the wearer of the eyeglass lens1may be referred to simply as “left-right direction”. The direction of the Z axis is an example of an up-down direction in the field of view of the wearer of the eyeglass lens1of the present invention. The up-down direction in the field of view of the wearer is a direction perpendicular to the left-right direction, for example. In the following, the up-down direction in the field of view of the wearer of the eyeglass lens1may be referred to simply as “up-down direction”. Furthermore, in the embodiments, the term “up” in the up-down direction refers to a direction from the mouth toward the nose of the wearer and the term “down” therein refers to a direction from the nose toward the mouth of the wearer, for example.

First Embodiment

The eyeglass lens1according to a first embodiment of the present invention will be described with reference toFIGS.1A to11. An embodiment of the eyeglass lens1is described first with reference toFIGS.1A and1B.FIG.1Ais a front-side view of the eyeglass lens1of the first embodiment when the eyeglass lens1is viewed from the front side of the eyeglass lens1. The eyeglass lens1has two surfaces one of which is the front surface located away from a wearer of the eyeglass lens1.FIG.1Bis a cross-sectional view taken along a line IB-IB inFIG.1A. As illustrated inFIG.1A, the eyeglass lens1includes a polarizing part10and a non-polarizing part20. Note that the polarizing part10and the non-polarizing part20are indicated by dot patterns with different densities in the drawings for the sake of easily distinguishing between the polarizing part10and the non-polarizing part20. The eyeglass lens1is a lens to be used for eyeglasses. The eyeglass lens1is any of a polarizing lens, a solid color lens, a coated lens, a protective lens, and a bifocal lens, for example. Note that the eyeglasses will be described later with reference toFIG.12.

The polarizing part10is adjacent to the non-polarizing part20. Specifically, the polarizing part10is adjacent to the non-polarizing part20in a direction intersecting with a thickness direction D of the eyeglass lens1. That is, the polarizing part10and the non-polarizing part20do not overlap with each other in the thickness direction D. The thickness direction D is a direction along the optical axis of the eyeglass lens1, for example. Also, the thickness direction D of the eyeglass lens1is the same as the thickness direction of the polarizing part10or the thickness direction of the non-polarizing part20, for example. For example, the polarizing part10and the non-polarizing part20are injection molded so as to be adjacent to each other. The polarizing part10has a polarizing function. Specifically, the polarizing part10includes a base part11and a polarizing sheet12. As illustrated inFIG.1B, the base part11and the polarizing sheet12are located to face each other in the thickness direction D.

The base part11is a light transmitting member. The base part11transmits light entering the base part11independent of the presence or absence of a polarization component contained in the light. The base part11is made of a colored resin. Specifically, the colored resin contains a colorant. The color of the colored resin is a transparent color, for example. The term transparent color herein means being colored and transparent. Examples of the transparent color include transparent blackish colors, transparent brownish colors, and transparent dark blueish colors. The base part11is made of a material such as a synthetic resin. Examples of the synthetic resin include polycarbonate, polyamide, polyethylene terephthalate, triacetate, and polyurethane. The base part11is thermoplastic, for example.

The polarizing sheet12is a polarizing member. The polarizing sheet12is a layered sheet, for example. The polarizing sheet12blocks a specific polarization component contained in light entering the polarizing sheet12. The specific polarization component is S polarized light, for example. The polarizing sheet12has a thickness W3of 0.3 mm to 0.6 mm, for example.

The polarizing sheet12is processed into a shape corresponding to the outer contour of the eyeglass lens1in a process of preparing the polarizing sheet12. For example, the polarizing sheet12is processed to have a substantially circular shape or a substantial semicircular shape. Furthermore, in the process of preparing the polarizing sheet12, the polarizing sheet12is bent into a shape corresponding to the shape of a curve of a specific lens. For example, the polarizing sheet12is bent into an arc in cross section with a specific curvature so as to protrude in a direction from a side close to the wearer toward a side away from the wearer.

The polarizing sheet12prepared is put for example in a mold in an injection molding apparatus (not illustrated) in a process of putting the polarizing sheet12in the mold. The injection molding apparatus includes an injection section, a mold, a mold clamping section, and a controller, for example. The injection section includes a hopper, a cylinder, and a spray nozzle, for example.

When the colored resin is melted and injected into the mold in which the polarizing sheet12is put, a light transmitting member2formed of the non-polarizing part20and the base part11is injection molded so that the polarizing sheet12and the base part11are in face contact with each other. The light transmitting member2is a single solid member.

The polarizing sheet12is in face contact with the base part11in a non-separable manner. The polarizing sheet12and the base part11are fused at an interface therebetween to be integral in injection molding, for example. As a result, the polarizing sheet12is non-separable from the base part11. Thereafter, the eyeglass lens1is taken out of the mold.

The non-polarizing part20is adjacent to the polarizing part10. The non-polarizing part20is a light transmitting member. The non-polarizing part20transmits light entering the non-polarizing part20independent of the presence or absence of a polarization component contained in the light. The non-polarizing part20is made of a colored resin. Specifically, the colored resin contains a colorant. The color of the colored resin is a transparent color, for example. Examples of the transparent color include transparent blackish colors, transparent brownish colors, and transparent dark blueish colors. The non-polarizing part20is made of a material such as a synthetic resin. Examples of the synthetic resin include polycarbonate, polyamide, polyethylene terephthalate, triacetate, and polyurethane. The non-polarizing part20is thermoplastic, for example.

The base part11and the non-polarizing part20form the light transmitting member2that is a single solid member. As such, the light transmitting member2is made of a colored resin. Specifically, the colored resin contains a colorant. The color of the colored resin is a transparent color, for example. Examples of the transparent color includes transparent blackish colors, transparent brownish colors, and transparent dark blueish colors. The light transmitting member2is made of a material such as a synthetic resin. Examples of the synthetic resin include polycarbonate, polyamide, polyethylene terephthalate, triacetate, and polyurethane. The light transmitting member2is thermoplastic, for example. The colored resin is generated for example as a result of a colored pellet being melted to be plastic before being injected (loaded) into the mold. The colored pellet includes a pellet that is colored, a natural pellet, and a masterbatch, for example. After the colored resin is loaded into the mold in which the polarizing sheet12is put, the light transmitting member2is injection molded out of the colored resin so that the polarizing sheet12is in face contact with the base part11in a non-separable manner. This colors the inside of the light transmitting member2. Preferably, the light transmitting member2is colored uniformly as a whole. Furthermore, the polarizing sheet12and the light transmitting member2are fused at the interface therebetween to be integral.

The non-polarizing part20has a thickness W1greater than a thickness W2of the base part11. For example, the thickness W1of the non-polarizing part20is equal to a sum of the thickness W2of the base part11and the thickness W3of the polarizing sheet12. The thickness W1of the non-polarizing part20is 2.0 mm, for example. The thickness W2of the base part11is 1.4 mm, for example. The thickness W3of the polarizing sheet12is 0.6 mm, for example. The light transmitting member2is made of a colored resin, and the color density of the non-polarizing part20is accordingly in proportion to the thickness W1of the non-polarizing part20. Similarly, the color density of the base part11is in proportion to the thickness W2of the base part11. As such, the color density of the non-polarizing part20is higher than the color density of the base part11.

For example, a manufacturer of the eyeglass lens1determines a ratio between transmittance of the non-polarizing part20and transmittance of the polarizing part10based on at least one of the color of the colored resin, the color density of the colored resin, and the thickness of the light transmitting member2in the process of injection molding the light transmitting member2out of the colored resin. Examples of the color of the colored resin include blackish colors, brownish colors, and dark blueish colors. The color density of the colored resin depends on the color density of the colored pellet, for example. The thickness of the light transmitting member2includes the thickness W1of the non-polarizing part20and the thickness W2of the base part11. The transmittance is visible transmittance, for example. In the following, the “transmittance of the non-polarizing part20” may be referred to as “non-polarizing transmittance”, and the “transmittance of the polarizing part10” may be referred to as “polarizing transmittance”.

In the first embodiment, the polarizing sheet12is put in the mold and the light transmitting member2, which is a single solid member, is injection molded out of the colored resin. As a result of the injection molding, the thickness W1of the non-polarizing part20is greater than the thickness W2of the base part11and the polarizing sheet12is in face contact with the base part11in a non-separable manner. This eliminates the need to provide a bonding layer of for example a bonding material between the polarizing sheet12and the base part11. Thus, change in transmittance due to the presence of the bonding layer can be reduced. Furthermore, due to the light transmitting member2being made of a colored resin, the color density of the non-polarizing part20is in proportion to the thickness W1of the non-polarizing part20, for example. Similarly, due to the light transmitting member2being made of a colored resin, and the color density of the base part11is in proportion to the thickness W2of the base part11, for example. As such, the color density of the non-polarizing part20and the color density of the polarizing part10can be adjusted by adjusting the thickness W1of the non-polarizing part20and the thickness W2of the base part11, respectively. This can achieve accurate adjustment of the transmittance of each of the polarizing part and the non-polarizing part.

Furthermore, the light transmitting member2is made of a colored resin in the first embodiment. For example, the light transmitting member2is molded by loading the colored resin into the mold. Therefore, the light transmitting member2has an inside that is colored. As such, the light transmitting member2can be colored substantially uniformly as a whole. This can reduce color irregularity of the eyeglass lens1resulting from for example abrasion on the surface of the eyeglass lens1. Thus, change in transmittance of the eyeglass lens1due to color irregularity can be reduced.

Furthermore, in the first embodiment, the polarizing sheet12is processed into a shape corresponding to the shape of the outer contour of the eyeglass lens1and bent into a shape corresponding to the shape of the curve of the eyeglass lens1in the process of preparing. The light transmitting member2is molded along the polarizing sheet12in the process of injection molding the light transmitting member2. As such, the light transmitting member2can be easily molded according to the entire shape of the eyeglass lens1.

Furthermore, the ratio between the polarizing transmittance and the non-polarizing transmittance is determined based on at least one of the color of the colored resin, the color density of the colored resin, and the thickness of the light transmitting member2in the process of injection molding the light transmitting member2in the first embodiment. Therefore, the number of steps for manufacturing eyeglass lenses1with various ratios between the polarizing transmittance and the non-polarizing transmittance can be reduced.

Moreover, the polarizing sheet12has an outer periphery12A. The outer periphery12A includes for example a part of the outer periphery12A and the other part of the outer periphery12A, for example. In the following, the “part of the outer periphery12A of the polarizing sheet12” may be referred to as “first outer peripheral segment12A1” and the “other part of the outer periphery12A of the polarizing sheet12” may be referred to as “second outer peripheral segment12A2”. The first outer peripheral segment12A1once connected to the non-polarizing part20serves as a boundary with the non-polarizing part20, for example. The first outer peripheral segment12A1is linear in a direction intersecting with the up-down direction in the field of view of the wearer, for example. The direction intersecting with the up-down direction in the field of view of the wearer is the left-right direction in the field of view of the wearer, for example. In a case in which the first outer peripheral segment12A1is linear, the polarizing sheet12has a shape of a missing circle, for example. Note that the first outer peripheral segment12A1may have a curved shape or a bent line shape, for example.

In a case in which the polarizing sheet12has a shape of for example a missing circle, the non-polarizing part20has a shape of a missing circle. In other words, in a case in which the outer periphery12A of the polarizing sheet12is composed of for example the first outer peripheral segment12A1and the second outer peripheral segment12A2, the non-polarizing part20is in contact with the first outer peripheral segment12A1and out of contact with the second outer peripheral segment12A2. Accordingly, the non-polarizing part20can be set further wide in the first embodiment. As a result, the field of view through the non-polarizing part20is hardly limited. Furthermore, a viewer in contact with the wearer recognizing the boundary between the polarizing part10and the non-polarizing part20may have an impression that the shape of the non-polarizing part20contributes to high level of design of the eyeglass lens1as a whole. Accordingly, design quality of the eyeglass lens1can be increased.

Detailed configuration of the eyeglass lens1will be described next with reference toFIGS.2A and2B.FIG.2Ais a cross-sectional view taken along a line IIB-IIB inFIG.1A.FIG.2Bis an enlarged partial view ofFIG.2A.

As illustrated inFIG.2A, the light transmitting member2includes an upper part2A and a lower part2B and the non-polarizing part20is located adjacent to the polarizing part10in the lower part2B of the light transmitting member2. Specifically, the upper part2A of the light transmitting member2corresponds to the upper part of a field of view VF of the wearer. Also, the lower part2B of the light transmitting member2corresponds to the lower part of the field of view VF of the wearer. The field of view VF is a field of view from an eye EY of the wearer wearing the eyeglass lens1.

The non-polarizing part20is located below the polarizing part10in the up-down direction. That is, the first outer peripheral segment12A1of the polarizing sheet12is located at the lower part of the polarizing sheet12. Accordingly, light passing through the non-polarizing part20mainly enters the lower part of the field of view VF in the first embodiment. As a result, dazzling brightness at the upper part and the central part of the field of view VF can be reduced and the wearer can view the lower part of the field of view VF through the non-polarizing part20more brightly than through the polarizing part10. The non-polarizing part20transmits light independent of the presence or absence of a polarization component contained in light entering the non-polarizing part20. Therefore, the wearer can easily view a liquid-crystal display especially at hand.

As illustrated inFIG.2B, the polarizing sheet12includes a polarizing film12B, a first cover layer12C, and a second cover layer12D. The polarizing film12B, the first cover layer12C, and the second cover layer12D are layered.

The polarizing film12B is a polarizer, and extracts a polarization component from non-polarized light, for example. The polarizing film12B is formed for example in a manner that a resin having a hydroxy group, such as a polyvinyl alcohol resin, is extended uniaxially and immersed in for example an iodine-based compound or a dichromatic dye. The polarizing film12B has a first surface12B1and a second surface12B2that is opposite to the first surface12B1. The polarizing film12B is sandwiched between the first cover layer12C and the second cover layer12D.

The first cover layer12C and the second cover layer12D protect the polarizing film12B in the polarizing sheet12. The first cover layer12C and the second cover layer12D each are a protective film, for example. The first cover layer12C and the second cover layer12D are each made of a synthetic resin such as polycarbonate or polyamide. Each of the first cover layer12C and the second cover layer12D is colorless and transparent, for example.

The first cover layer12C covers the first surface12B1of the polarizing film12B. Specifically, the first cover layer12C has a first cover surface12C1and a second cover surface12C2opposite to the first cover surface12C1. The first cover surface12C1serves as the front surface of the polarizing sheet12in a direction from the base part11toward the polarizing sheet12, that is, a downstream surface. The second cover surface12C2and the first surface12B1of the polarizing film12B face each other in contact with each other. For example, the second cover surface12C2is in close contact with the first surface12B1.

The second cover layer12D covers the second surface12B2of the polarizing film12B. Specifically, the second cover layer12D has a third cover surface12D1and a fourth cover surface12D2opposite to the third cover surface12D1. The third cover surface12D1and the second surface12B2of the polarizing film12B face each other in contact with each other. For example, the third cover surface12D1is in close contact with the second surface12B2.

The base part11has a first base surface11A and a second base surface11B. The first base surface11A and the second base surface11B are opposite to each other in the thickness direction D of the eyeglass lens1. In the following, in the thickness direction D of the eyeglass lens1, a direction from the base part11toward the polarizing sheet12may be referred to as first direction D1and a direction from the polarizing sheet12toward the base part11may be referred to as second direction D2. Note that the first direction D1may for example be a direction from the rear surface toward the front surface of the eyeglass lens1or a direction from the wearer wearing the eyeglass lens1toward the eyeglass lens1.

The second cover layer12D is in face contact with the base part11. Specifically, the fourth cover surface12D2of the second cover layer12D is in face contact with the first base surface11A of the base part11. In a case in which the material of the base part11is polycarbonate, it is preferable that the material of the second cover layer12D is also polycarbonate, for example. That is, it is preferable that the second cover layer12D and the base part11are made of the same material. In the first embodiment, as a result of the second cover layer12D and the base part11being made of the same material, the second cover layer12D and the base part11are easily fused at the interface therebetween to be integral in injection molding of the light transmitting member2. As such, the polarizing sheet12and the base part11can be easily brought into face contact with each other.

Furthermore, the material of the first cover layer12C is preferably the same as the material of the second cover layer12D and the base part11in the first embodiment. As a result of the first cover layer12C, the second cover layer12D, and the light transmitting member2being made of the same material as above, the light transmitting member2and the polarizing sheet12can be easily fused at the interface therebetween. In addition, when the surfaces of the polarizing part10and the non-polarizing part20are coated with a hard layer as whole, the hard layer hardly separates from the first cover layer12C. The hard layer is a hard film provided by hard coating, for example. Therefore, various effects of coating on the eyeglass lens1can be exerted for a long period of time.

Moreover, the non-polarizing part20has a first non-polarizing surface20A and a second non-polarizing surface20B. The first non-polarizing surface20A and the second non-polarizing surface20B are opposite to each other in the thickness direction D of the eyeglass lens1. The first non-polarizing surface20A is the front surface of the non-polarizing part20in the first direction D1, that is, the downstream surface. The second non-polarizing surface20B is the rear surface of the non-polarizing part20in the first direction D1, that is, the upstream surface.

The second non-polarizing surface20B of the non-polarizing part20serves as one main surface of two main surfaces of the light transmitting member2in combination with the second base surface11B of the base part11. Specifically, the light transmitting member2has a first main surface2C and a second main surface2D opposite to the first main surface2C. The second non-polarizing surface20B of the non-polarizing part20serves as the second main surface2D of the light transmitting member2, which is the rear surface of the eyeglass lens1, in combination with the second base surface11B of the base part11. Preferably, the second non-polarizing surface20B and the second base surface11B are aligned with each other.

The first non-polarizing surface20A of the non-polarizing part20and the first cover surface12C1of the polarizing sheet12serve as the front surface of the eyeglass lens1in combination. The first non-polarizing surface20A and the first cover surface12C1are preferably aligned with each other. The first non-polarizing surface20A and the first cover surface12C1can be molded to be aligned with each other for example by injection molding the light transmitting member2with the polarizing sheet12put in the mold. In the first embodiment, as a result of the first cover layer12C and the non-polarizing part20being aligned with each other, design quality of the front surface of the eyeglass lens1can be increased. Furthermore, processing for various types of coating on the front surface of the eyeglass lens1can be facilitated. In particular, in a case in which the light transmitting member2and the first cover layer12C are made of the same material and the first cover layer12C and the non-polarizing part20are aligning with each other, the first non-polarizing surface20A of the non-polarizing part20and the first cover surface12C1are integrally fused easily in the process of injection molding the light transmitting member2. As a result, continuity between the first non-polarizing surface20A and the first cover surface12C1is increased.

An example of a method for determining a ratio between the transmittance of the polarizing part10and the transmittance of the non-polarizing part20will be described next with reference toFIGS.1A to3.FIG.3is a graph representation showing a relationship between categories of the transmittance of the polarizing part10and categories of the transmittance of the non-polarizing part20in the eyeglass lens1according to the first embodiment.

For example,FIG.3shows an example of various combinations of the transmittance of the polarizing part10and the transmittance of the non-polarizing part20for determination of the ratio between the transmittance of the polarizing part10and the transmittance of the non-polarizing part20. The horizontal axis indicates the transmittance (non-polarizing transmittance, unit: %) of the non-polarizing part20while the vertical axis indicates the transmittance (polarizing transmittance, unit: %) of the polarizing part10. Each transmittance is visible transmittance, for example. The transmittance is classified into a plurality of categories according to its level. For example, categories defined in International Organization for Standardization (ISO) or Japanese Industrial Standard (JIS) can be adopted to the categories. In an example, the plurality of categories include 5 categories defined in “ISO 8980-3:2013”.

For example, the manufacturer of the eyeglass lens1can determine a combination of the polarizing transmittance and the non-polarizing transmittance based on 4 categories out of the 5 different categories. The polarizing transmittance falls into any one of the 4 categories. The non-polarizing transmittance also falls into any one of the 4 categories. The 4 categories include a first category, a second category, a third category, and a fourth category.

The first category corresponds to “Category 1” defined in ISO. The first category corresponds to light shades, for example. A transmittance of in a range of greater than 43% and no greater than 80% falls into the first category, for example. In the following, the first category for a non-polarizing transmittance may be referred to as “first category CX1” and the first category for a polarizing transmittance may be referred to as “first category CY1” for the sake of convenience.

The second category corresponds to “Category 2” defined in ISO. The second category corresponds to intermediate shades, for example. A transmittance of in a rage of greater than 18% and no greater than 43% falls into the second category, for example. In the following, the second category for a non-polarizing transmittance may be referred to as “second category CX2” and the second category for a polarizing transmittance may be referred to as “second category CY2” for the sake of convenience.

The third category corresponds to “Category 3” defined in ISO. The third category corresponds to dark shades, for example. A transmittance of in a range of greater than 8% and no greater than 18% falls into the third category, for example. In the following, the third category for a non-polarizing transmittance may be referred to as “third category CX3” and the third category for a polarizing transmittance may be referred to as “third category CY3” for the sake of convenience.

The fourth category corresponds to “Category 4” defined in ISO. The fourth category corresponds to very dark shades, for example. A transmittance of in a range of greater than 3% and no greater than 8% falls into the fourth category, for example. In the following, the fourth category for a non-polarizing transmittance may be referred to as “fourth category CX4” and the fourth category for a polarizing transmittance may be referred to as “fourth category CY4” for the sake of convenience.

Note that the remaining category of the 5 categories other than the first category, the second category, the third category, and the fourth category corresponds to “Category 0” defined in ISO. “Category 0” corresponds to transparent or very light shades, for example. A transmittance of in a range of greater than 80% and no greater than 100% falls into “Category 0”, for example. The manufacturer of the eyeglass lens1may determine the combination of the non-polarizing transmittance and the polarizing transmittance based on the four categories and “Category 0”. In the following, a category for a non-polarizing transmittance corresponding to “Category 0” may be referred to as “category CX0” and a category for a polarizing transmittance corresponding to “Category 0” may be referred to as “category CY0” for the sake of convenience.

Examples of the combination to be determined in a process of determining the combination of the non-polarizing transmittance and the polarizing transmittance include combinations P1to P13. The combinations P1to P13include: a combination of the category CX0and the first category CY1; a combination of the category CX0and the second category CY2; a combination of the category CX0and the third category CY3; a combination of the category CX0and the fourth category CY4; a combination of the first category CX1and the first category CY1; a combination of the first category CX1and the second category CY2; a combination of the first category CX1and the third category CY3; a combination of the first category CX1and the fourth category CY4; a combination of the second category CX2and the second category CY2; a combination of the second category CX2and the third category CY3; a combination of the second category CX2and the fourth category CY4; a combination of the third category CX3and the third category CY3; and a combination of the third category CX3and the fourth category CY4. Note that it is preferable that the polarizing transmittance does not exceed the non-polarizing transmittance in each of the combinations P1to P13.

In the first embodiment, in a case in which the combination of the non-polarizing transmittance and the polarizing transmittance is for example the combination P9(combination of the second category CX2and the second category CY2), the combination P10(combination of the second category CX2and the third category CY3), or the combination P12(combination of the third category CX3and the third category CY3), the non-polarizing transmittance and the polarizing transmittance can be adjusted with accuracy and the eyeglass lens1can be suitable for general purpose. Furthermore, the non-polarizing part20can be inconspicuous relative to the polarizing part10. In particular, in a case with a combination in which the non-polarizing transmittance and the polarizing transmittance are substantially equal to each other in the eyeglass lens1, the non-polarizing part20can be further inconspicuous relative to the polarizing part10.

Moreover, in the first embodiment, in a case in which the combination of the non-polarizing transmittance and the polarizing transmittance is for example the combination P11(combination of the second category CX2and the fourth category CY4) or the combination P13(combination of the third category CX3and the fourth category CY4), the non-polarizing transmittance and the polarizing transmittance can be adjusted with accuracy and the eyeglass lens1can be suitable for various special purposes. Examples of the special purposes include applications for welding operations and purposes of protecting eyes from for example special ultraviolet rays or laser light beams.

Furthermore, in the first embodiment, in a case in which the combination of the non-polarizing transmittance and the polarizing transmittance is for example the combination P8(combination of the first category CX1and the fourth category CY4), a blight object and a dark object can be visually recognized even when the wearer is in a dark place. It becomes easy for example in an operation carrying out near a blast furnace to visually observe a bright blast furnace through the polarizing part10, visually observe a manual at hand through the non-polarizing part20in the dark, and visually observe a liquid-crystal display at hand through the non-polarizing part20. It also becomes easy for example to visually observe bright outside world through a window from a dark boat room and visually observe a liquid-crystal display of a smartphone at hand. In addition, the non-polarizing transmittance and the polarizing transmittance can be adjusted with accuracy and fashionable appearance owing to contrast between the shape of the polarizing part10and the shape of the non-polarizing part20can be appealed.

With an increase in transmittance of the non-polarizing part20, the boundary between the polarizing part10and the non-polarizing part20becomes conspicuous in the eyeglass lens1regardless of the combination of the category for the polarizing part10and the category for the non-polarizing part20. As such, the non-polarizing part20can be inconspicuous for the viewer in contact with the wearer by setting the transmittance of the non-polarizing part20to for example no greater than 50% in the first embodiment. By contrast, the contrast between the polarizing part10and the non-polarizing part20can be emphasized to the viewer by setting the transmittance of the non-polarizing part20to for example greater than 50% in the first embodiment.

The present invention will be further described based on an example with reference toFIG.4. However, the present invention is not limited to the following example. Note that experimental conditions were as follows.Six subjects performed a sensory test on a plurality of eyeglass lenses1.The subjects viewed each eyeglass lens1put on a table from the front side thereof, and evaluated in 3 levels. The subjects also viewed the eyeglass lens1reflected by a mirror in a state in which the eyeglass lens1is put in front of the eye, and evaluated in 3 levels. Respective scores on the 3 levels are 1, 2, and 3.The evaluation was performed on the eyeglass lenses1that each included any one of a plurality of polarizing sheets12with mutually different transmittances and any one of a plurality of light transmitting members2with mutually different transmittances in combination. The polarizing sheet12of each eyeglass lens1had a thickness of 0.6 mm, the base part11thereof had a thickness of 1.4 mm, and the non-polarizing part20thereof had a thickness of 2.0 mm.

FIG.4is a graph representation showing a relationship between the non-polarizing transmittance and conspicuousness of the boundary between the polarizing part10and the non-polarizing part20when each of eyeglass lenses of the example of the present invention is viewed from the front side thereof. The horizontal axis indicates the non-polarizing transmittance (unit: %) while the vertical axis indicates conspicuousness (unit: score) of the boundary between the polarizing part10and the non-polarizing part20when each of the eyeglass lenses1was viewed from the front side thereof. Black circles inFIG.4each indicate the average of the evaluation scores by the subjects for a corresponding one of the eyeglass lenses1.

As shown inFIG.4, the boundary between the polarizing part10and the non-polarizing part20became conspicuous as the non-polarizing transmittance was increased. For example, when the non-polarizing transmittance was no greater than 50%, the boundary was inconspicuous due to the fact that the score for conspicuousness of the boundary was at least 1.5, which is an intermediate value for conspicuous of the boundary. Therefore, it was confirmed that the presence of the non-polarizing part20was made inconspicuous to the viewer in contact with the wearer through the non-polarizing transmittance being set to 50% or less.

When the non-polarizing transmittance was greater than 50% by contrast, the boundary was conspicuous due to the fact that the score for conspicuous of the boundary was less than 1.5, which is the intermediate value for conspicuousness of the boundary. As such, it was confirmed that contrast between the polarizing part10and the non-polarizing part20was emphasized to the viewer in contact with the wearer through the transmittance of the non-polarizing part20being set to greater than 50%. Therefore, it was confirmed that fashionable appearance owing to contrast between the shape of the polarizing part10and the shape of the non-polarizing part20can be appealed.

Detailed configuration of the eyeglass lens1of the first embodiment will be described next with reference toFIG.5.FIG.5is a cross-sectional view of the eyeglass lens1according to the first embodiment. As illustrated inFIG.5, the eyeglass lens1may further include a reflective layer30. The reflective layer30covers the polarizing sheet12and the non-polarizing part20on the front side of the eyeglass lens1in the first direction D1, that is, the downstream side. That is, the reflective layer30is a layer coating the front surface of the eyeglass lens1. The reflective layer30reflects part of light entering the eyeglass lens1and transmits another part of the light. For example, the reflective layer30is a mirror coat layer. For example, the mirror coat layer is a blueish mirror coat layer (e.g., a blue mirror) or a silvery mirror coat layer (e.g., a silver mirror).

In the first embodiment, as a result of the reflective layer30being provided on the polarizing sheet12and the non-polarizing part20, the polarizing sheet12and the non-polarizing part20can be covered with the reflective layer30as a whole and the reflective layer30can reflect part of light. As s a result, the viewer in contact with the wearer hardly recognizes the boundary between the polarizing sheet12and the non-polarizing part20. Also, the edge of the non-polarizing part20can be further inconspicuous.

Furthermore, in the first embodiment, the ratio of the polarizing transmittance to the non-polarizing transmittance is preferably in a range from approximately 30% or more and approximately 70% or less, for example, as a range in which the boundary between the polarizing sheet12and the non-polarizing part20is especially unrecognizable to the viewer. For example, the ratio of the polarizing transmittance to the non-polarizing transmittance can be set within the range from approximately 30% or more and approximately 70% or less by adjusting the color density of the colored resin or adjusting the thickness of the light transmitting member2in the process of injection molding the light transmitting member2out of the colored resin with the polarizing sheet12put in the mold. The edge of the non- polarizing part20can be made effectively inconspicuous by setting the ratio of the polarizing transmittance to the non-polarizing transmittance to be in a range such as above.

An example of the present invention will be described next in detail with reference toFIG.6. However, the present invention is not limited to the following example. Note that experimental conditions were as follows.Six subjects performed a sensory test on a plurality of eyeglass lenses1.The subjects viewed each of the eyeglass lenses1put on a table from the front side thereof, and evaluated in 3 levels. The subjects also viewed the eyeglass lens1reflected by a mirror in a state in which the eyeglass lens1is put in front of the eye, and evaluated in 3 levels. Respective scores on the 3 levels are 1, 2, and 3.As to an eyeglass lens1not including the reflective layer30, the evaluation was performed on eyeglass lenses1that each included any one of a plurality of polarizing sheets12with mutually different transmittances and any one of a plurality of light transmitting members2with mutually different transmittances in combination. The polarizing sheet12of each eyeglass lens1had a thickness W3of 0.6 mm, the base part11thereof had a thickness W2of 1.4 mm, and the non-polarizing part20thereof had a thickness W1of 2.0 mm.As to an eyeglass lens1including the reflective layer30, the evaluation was performed also on eyeglass lenses1that each included one of two reflective layers in mutually different colors, any one of the polarizing sheets12with mutually different transmittances, and any one of the light transmitting members2with mutually different transmittances in combination. The two reflective layers30were a blue mirror and a silver mirror. The polarizing sheet12of each eyeglass lens1had a thickness W3of 0.6 mm, the base part11thereof had a thickness W2of 1.4 mm, and the non-polarizing part20thereof had a thickness W1of 2.0 mm.

FIG.6is a graph representation showing a relationship between the ratio of the transmittance of the polarizing part10to the transmittance of the non-polarizing part20and conspicuousness of the boundary between the polarizing part10and the non-polarizing part20when each of the eyeglass lenses1in the example of the present invention was viewed from the front side thereof. The horizontal axis indicates the ratio of the transmittance of the polarizing part10to the transmittance of the non-polarizing part20while the vertical axis indicates conspicuousness of the boundary between the polarizing part10and the non-polarizing part20when each eyeglass lens1was viewed from the front side thereof. The experiment was performed for each of a case of an eyeglass lens1including the reflective layer30and a case of an eyeglass lens1not including the reflective layer30. Circles, squares, and triangles inFIG.6each indicate the average of the evaluation scores by the subjects for a corresponding one of the eyeglass lenses1. Note that the circles indicate a case with a blue mirror while the squares indicate a case with the silver mirror in the case with the reflective layer30inFIG.6. Also, the triangles indicate the case without the reflective layer30.

As shown inFIG.6, when eyeglass lenses1were compared that had the same ratio of the polarizing transmittance to the non-polarizing transmittance in a range from approximately 30% or more and approximately 70% or less, the eyeglass lenses1including the reflective layer30had higher evaluation scores than the eyeglass lenses1not including the reflective layer30. Note that approximately 30% refers to a percentage including for example 28% as can be clear from the drawing. Also, approximately 70% refers to a percentage including for example 72% as can be clear from the drawing. As such, it was confirmed that the boundary between the polarizing part10and the non-polarizing part20was inconspicuous in the case with the reflective layer30than in the case without the reflective layer30when the ratio of the polarizing transmittance to the non-polarizing transmittance was in a range from approximately 30% or more and approximately 70% or less. It was additionally confirmed that the blue mirror was more inconspicuous than the silver mirror as the reflective layer30.

A further detailed configuration of the eyeglass lens1of the first embodiment will be described next with reference toFIGS.7A and7B.FIG.7Ais a front-side view of the eyeglass lens1when the eyeglass lens1is viewed from the front side thereof.FIG.7Bis a cross-sectional view taken along a line VIIB-VIIB inFIG.7A. As illustrated inFIGS.7A and7B, the polarizing sheet12may have a hole12E. Specifically, the hole12E corresponds to a cutout part of the polarizing sheet12. The non-polarizing part20is located in the hole12E. Specifically, the hole12E is formed in the polarizing sheet12in the process of preparing the polarizing sheet12. In an embodiment in which the polarizing sheet12has a hole12E, the non-polarizing part20is in contact with the hole12E of the polarizing sheet12, that is, the inner periphery of the polarizing sheet12, and out of contact with the outer periphery12A of the polarizing sheet12.

When the non-polarizing part20is located in the hole12E of the polarizing sheet12as above in the first embodiment, the ratio of the transmittance of the non-polarizing part20to the transmittance of the polarizing part10can be easily set so as to reduce dazzling brightness of light entering the non-polarizing part20. As a result, the wearer convenience can be further increased and the non-polarizing part20can become further inconspicuous.

A configuration of an eyeglass lens1according to a variation of the first embodiment will be described next with reference toFIGS.8A and8B.FIG.8Ais a front-side view of the eyeglass lens1of the variation of the first embodiment when the eyeglass lens1is viewed from the front side thereof.FIG.8Bis a cross-sectional view taken along a line VIIIB-VIIIB inFIG.8A. As illustrated inFIGS.8A and8B, the eyeglass lens1may further include a myopic part40. The myopic part40has refractive power for near view. The near view refers to a spot at the wearer's hand or a tabletop when the wearer is seated, for example. In detail, the myopic part40has a refractive power necessary to correct farsightedness caused by for example presbyopia. When the myopic part40is viewed in the second direction D2, the myopic part40has a shape of a missing circle, for example. Note that the myopic part40may be rectangular in shape, for example.

The myopic part40is located along the rear surface of the non-polarizing part20in the first direction D1, that is, on the second non-polarizing surface20B. For example, the myopic part40is molded to be disposed along the non-polarizing part20in the process of injection molding. For example, the myopic part40is molded as a single solid member together with the light transmitting member2. In the first embodiment, even if the wearer has presbyopia, the wearer can easily view a liquid-crystal display at hand while dazzling brightness can be reduced by the polarizing part10.

Note that althoughFIGS.8A and8Billustrate an embodiment in which the non-polarizing part20is in contact with the first outer peripheral segment12A1and out of contact with the second outer peripheral segment12A2, the myopic part40may be located along the non-polarizing part20even in the embodiment (FIGS.7A and7B) in which the polarizing sheet12has the hole12E. For example, the myopic part40may be located along the second non-polarizing surface20B of the non-polarizing part20across the hole12E.

An example of a manufacturing method of the eyeglass lens1will be described next with reference toFIGS.1A to9.FIG.9is a flowchart depicting a method for manufacturing the eyeglass lens1. Through the processes of Steps S101to Step S111being performed, the eyeglass lens1is manufactured. Details are as follows.

In Step S101, a combination of the transmittance of the polarizing part10and the transmittance of the non-polarizing part20is determined based on the 4 categories among the mutually different 5 categories. The routine proceeds to Step S103.

In the next Step S103, the polarizing sheet12is prepared. The routine proceeds to Step S105.

In the next Step S105, the polarizing sheet12is put in the mold. The routine proceeds to Step S107.

In the next Step S107, the colored resin is melted and injected into the mold in which the polarizing sheet12is put for injection molding of the light transmitting member2, which is a single solid member, so that the polarizing sheet12is in face contact with the base part11. The eyeglass lens1is taken out of the mold then. The routine proceeds to Step S109.

In the next Step S109, the surfaces of the polarizing part10and the non-polarizing part20are coated with a hard layer as a whole. The routine proceeds to Step S111.

In the next Step S111, the reflective layer30is coated on the polarizing sheet12and the non-polarizing part20on the front side of the eyeglass lens1in the first direction D1. The routine ends then.

Note that the processes of Steps S101, S109, and S111inFIG.9may be omitted.

Details of the process of preparing the polarizing sheet12will be described herein with reference toFIGS.1A to10.FIG.10is a flowchart depicting an example of the process of preparing the polarizing sheet12. Through the processes of Steps S1031to S1035being performed, the process of preparing the polarizing sheet12is performed. Details are as follows.

In Step S1031, the polarizing sheet12is processed into a shape corresponding to the outer contour of the eyeglass lens1. The routine proceeds to Step S1033.

In the next Step S1033, the polarizing sheet12is bent into a shape corresponding to a curve of a specific lens. The routine proceeds to Step S1035.

In the next Step S1035, the hole12E is formed in the polarizing sheet12. The routine ends then.

Note that the polarizing sheet12may be processed into a shape with the first outer peripheral segment12A1and the second outer peripheral segment12A2in the process of Step S1031among the processes depicted inFIG.10. In the above case, the process of Step S1035may be omitted.

The detailed description of the process of injection molding the light transmitting member2out of the colored resin will be described next herein with reference toFIGS.1A to11.FIG.11is a flowchart depicting an example of the process of injection molding the light transmitting member2out of the colored resin. Through the processes of Steps S1071and S1073being performed, the process of injection molding the light transmitting member2out of the colored resin is performed. Details are as follows.

In Step S1071, the colored resin is melted and injected into the mold in which the polarizing sheet12is put. The routine proceeds to Step S1073.

In the next Step S1073, the myopic part40is molded to be disposed along the non-polarizing part20. The routine ends then.

Note that the process of Step S1073may be omitted among the processes depicted inFIG.11.

Second Embodiment

Eyeglasses100including the eyeglass lenses1of the first embodiment will be described next with reference toFIG.1A to12.FIG.12is a perspective view of the eyeglasses100according to a second embodiment of the present invention when the eyeglasses100are viewed from the front side of the eyeglass lenses1. As illustrated inFIG.12, the eyeglasses100include eyeglass lenses1and a support110. The eyeglasses100are sunglasses, nearsighted glasses, farsighted glasses, bifocals, or a light-shielding tool, for example. Each of the eyeglass lenses1includes the polarizing part10and the non-polarizing part20. Furthermore, the eyeglass lens1may further include the reflective layer30(seeFIG.5) and/or further include the myopic part40(seeFIGS.8A and8B).

The support110supports the eyeglass lenses1. The support110supports the paired eyeglass lenses1, for example. Note that the support110may have a configuration to support a single eyeglass lens1. The support110includes a rim111, a bridge112, and a temple113, for example.

In the second embodiment, as a result of the eyeglasses100including the eyeglass lenses1and the support110, the eyeglass lenses1including the polarizing parts and the non-polarizing parts each with accurately adjusted transmittance can be easily worn.

Embodiments of the present invention have been described so far with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments and can be practiced in various ways within the scope without departing from the essence of the present invention. Furthermore, appropriate combination of elements of configuration disclosed in the above embodiments enables formation of various inventions. For example, some elements of configuration may be omitted from all the elements of configurations indicated in the embodiments. Additionally, elements of configuration in different embodiments may be combined as appropriate. The drawings are schematic illustrations that emphasize elements of configuration in order to facilitate understanding thereof, and properties such as thickness, length, number, and interval of each of the elements of configuration illustrated in the drawings may differ from the actual properties thereof in order that elements of configuration can be easily illustrated. In addition, the material, shape, dimension, and the like of each of the elements of configuration indicated in the embodiments are only examples and not limited specifically. They can be altered in various ways within the scope without departing from the configuration of the present invention.

(1) As describe with reference toFIGS.1A to12, the base part11and the non-polarizing part20are thermoplastic. However, the present invention is not limited thereto. It is only required that the base part11and the non-polarizing part20form the light transmitting member that is a single solid member made of a colored resin. For example, the base part11and the non-polarizing part20may be thermosetting. In a case in which the base part11and the non-polarizing part20are made of a thermosetting resin, a light transmitting member that is formed of the base part11and the non-polarizing part20and that is a single solid member made of a colored resin can be formed for example by compression molding.

INDUSTRIAL APPLICABILITY

The present invention is applicable to the fields of eyeglass lenses, eyeglasses, and eyeglass lens manufacturing methods.

REFERENCE SIGNS LIST

1eyeglass lens10polarizing part11base part12polarizing sheet2light transmitting member20non-polarizing partW1, W2thickness