Spectacle lens evaluation method

Abstract

The purpose of the present disclosure is to provide a spectacle lens evaluation method capable of evaluating brightness of a field of view through a spectacle lens which includes an anti-reflection film. A spectacle lens evaluation method according to the present disclosure is an evaluation method for a spectacle lens comprising: a spectacle lens base material having a first main surface and a second main surface; and an anti-reflection film disposed on the first main surface and / or on the second main surface of the spectacle lens base material. The method comprises: a step for, when an angle formed by an optical axis of the spectacle lens base material and entry light entering from the first main surface side is set as an angle θ, performing prescribed reflectance measurement for a plurality of angles in a range of 0-60° as said angle θ; a step for calculating a TAR (θ) and a TID (θ), which are differences in prescribed transmittances for each angle set as the angle θ; a step for obtaining a value X by summing M1 (θ) values, each of which is the product of said TAR (θ) and a prescribed DC (θ); a step for obtaining a value Y by summing M2 (θ) values, each of which is the product of said TID (θ) and said DC (θ); and a step for calculating a specific parameter obtained by dividing the value X by the value Y.

Description

Eyeglass lens evaluation method

[0001] The present disclosure relates to a method for evaluating eyeglass lenses.

[0002] Various studies have been conducted on spectacle lenses. For example, Patent Document 1 describes a spectacle lens in which low refractive index layers and high refractive index layers are alternately laminated on a substrate as an antireflection film.

[0003] International Publication No. 2021 / 060554

[0004] The present disclosure provides a method for evaluating a spectacle lens comprising a spectacle lens substrate having a first principal surface and a second principal surface, and an anti-reflection coating disposed on at least one of the first principal surface and the second principal surface of the spectacle lens substrate, the method comprising the steps of performing reflectance measurement 1, reflectance measurement 2, reflectance measurement 3, and reflectance measurement 4 (described later) at a plurality of angles θ in a range of 0 to 60°, and measuring a transmittance T １ (θ) and the transmittance T ２ (θ) and the difference T ＡＲ (θ), and the transmittance T expressed by 100 and equation (2) Ｓ (θ) and the difference T ＩＤ (θ), and calculating T at each angle θ ＡＲ (θ) and the following D Ｃ (θ) and M １ (θ) is calculated, and M at each calculated angle θ is calculated. １ (θ) to obtain the value X, and T at each angle θ ＩＤ (θ) and D Ｃ (θ) and M ２ (θ) is calculated, and M at each calculated angle θ is calculated. ２ (θ) to obtain a value Y; and calculating a specific parameter obtained by dividing the value X by the value Y.

[0005] FIG. 1 is a cross-sectional schematic diagram for explaining reflectance measurement 1 and reflectance measurement 2 in the eyeglass lens evaluation method. FIG. 2 is a cross-sectional schematic diagram for explaining reflectance measurement 2 and reflectance measurement 4 in the eyeglass lens evaluation method. FIG. 3 is a cross-sectional schematic diagram of eyeglasses using an eyeglass lens subjected to the eyeglass lens evaluation method of the present disclosure when worn. FIG. 4 is a cross-sectional view of one embodiment of an eyeglass lens subjected to the eyeglass lens evaluation method of the present disclosure.

[0006] The spectacle lens evaluation method of the present disclosure will be described in detail below. The spectacle lens evaluation method is required to be able to evaluate the brightness of the field of view through a spectacle lens including an anti-reflection coating in a bright environment. The spectacle lens evaluation method of the present disclosure is capable of evaluating the brightness of the field of view through a spectacle lens including an anti-reflection coating. In this disclosure, the term "to" is used to mean that the numerical values ​​before and after it are included as the lower and upper limits. In this disclosure, the refractive index refers to the refractive index at the e-line unless otherwise specified.

[0007] <Method for Evaluating Spectacle Lenses> The method for evaluating spectacle lenses of the present disclosure is a method for evaluating spectacle lenses comprising a spectacle lens substrate having a first principal surface and a second principal surface, and an anti-reflection coating disposed on at least one of the first principal surface and the second principal surface of the spectacle lens substrate. The spectacle lens evaluation method of the present disclosure includes a step of performing reflectance measurement 1, reflectance measurement 2, reflectance measurement 3, and reflectance measurement 4 (to be described later) at a plurality of angles θ in the range of 0 to 60°, where θ is the angle formed between the optical axis of the spectacle lens substrate and incident light incident from the first principal surface side (hereinafter also referred to as the "reflectance measurement step"). The spectacle lens evaluation method of the present disclosure also includes a step of measuring a transmittance T １ (θ) and the transmittance T ２ (θ) and the difference T ＡＲ (θ), and the transmittance T expressed by 100 and the above formula (2) ２ (θ) and the difference T ＩＤ The spectacle lens evaluation method of the present disclosure also includes a step of calculating the T (θ) at each of the angles θ (hereinafter also referred to as a "transmittance calculation step").ＡＲ (θ) and D Ｃ (θ) and M １ (θ) is calculated, and the M １ (θ) to calculate the value X (hereinafter also referred to as the "value X calculation step"). ＩＤ (θ) and the above D Ｃ (θ) and M ２ (θ) is calculated, and the M ２ (θ) to obtain a value Y (hereinafter also referred to as a "value Y calculation step"). The spectacle lens evaluation method of the present disclosure also includes a step of calculating a specific parameter obtained by dividing the value X by the value Y (hereinafter also referred to as a "specific parameter calculation step"). Each of the above steps included in the spectacle lens evaluation method of the present disclosure will be described below. Note that detailed aspects of the spectacle lens to be subjected to the spectacle lens evaluation method of the present disclosure will be described in detail later.

[0008] [Reflectance Measurement Step] The spectacle lens evaluation method of the present disclosure includes a reflectance measurement step. In the reflectance measurement step, when the angle between the optical axis of the spectacle lens substrate and incident light incident from the first principal surface side is defined as angle θ, the following reflectance measurement 1, reflectance measurement 2, reflectance measurement 3, and reflectance measurement 4 are performed at a plurality of angles in the range of 0 to 60° as angle θ. Reflectance Measurement 1: Incident light is incident from the first principal surface side of the spectacle lens at the angle θ, and the reflectance R １ Reflectance measurement 2: Incident light is incident from the first principal surface side of the spectacle lens at the angle θ, and the reflectance R ２ Reflectance measurement 3: Incident light is incident from the first principal surface side of the eyeglass lens substrate at the angle θ, and the reflectance R Ｓ１ Reflectance measurement 4: Incident light is incident from the first principal surface side of the eyeglass lens substrate at the angle θ, and the reflectance R (θ) on the second principal surface side of the eyeglass lens substrate is measured. Ｓ２(θ) is measured. １ (θ), reflectance R ２ (θ), reflectance R Ｓ１ (θ) and reflectance R Ｓ２ The unit of (θ) is %.

[0009] Reflectance measurements 1 and 2 will be described with reference to the drawings. FIG. 1 is a cross-sectional schematic diagram illustrating the measurement of reflectance by irradiating incident light onto a spectacle lens. FIG. 1 illustrates a state in which incident light L1 is incident on a spectacle lens 10. The spectacle lens 10 includes a spectacle lens substrate 20 having a first principal surface S1 and a second principal surface S2, a first anti-reflection coating 18a disposed on the first principal surface S1 side of the spectacle lens substrate 20, and a second anti-reflection coating 18b disposed on the second principal surface S2 side of the spectacle lens substrate 20.

[0010] In Fig. 1, incident light L1 is incident from the first principal surface S1 side of the spectacle lens substrate 20 so that the angle it forms with the optical axis of the spectacle lens substrate 20 is θ. When incident light L1 is incident on the spectacle lens 10, reflected light RL1 is generated on the first principal surface S1 side (first anti-reflection coating 18a side) of the spectacle lens 10, and reflected light RL2 is generated on the second principal surface S2 side (second anti-reflection coating 18b side) of the spectacle lens 10. In reflectance measurement 1, the reflectance R １ That is, in reflectance measurement 1, the reflected light RL1 in FIG. 1 is measured, and the reflectance R １ Similarly, in reflectance measurement 2, the reflectance R on the second main surface S2 side of the spectacle lens 10 is measured at a plurality of angles in the θ range of 0 to 60°. ２ That is, in the reflectance measurement 2, the reflected light RL2 in FIG. 1 is measured, and the reflectance R ２ (θ) is measured.

[0011] Reflectance Measurement 3 and Reflectance Measurement 4 will be described with reference to the drawings. Fig. 2 is a cross-sectional schematic diagram showing how incident light is incident on a spectacle lens substrate to measure reflectance. Fig. 2 shows a state in which incident light L2 is incident on a spectacle lens substrate 20. The spectacle lens substrate 20 has a first principal surface S1 and a second principal surface S2.

[0012] 2, incident light L2 is incident from the first principal surface S1 side of the eyeglass lens substrate 20 so that the angle it forms with the optical axis of the eyeglass lens substrate 20 is θ. When incident light L2 is incident on the eyeglass lens substrate 20, reflected light RL3 is generated on the first principal surface S1 side of the eyeglass lens substrate 20, and reflected light RL4 is generated on the second principal surface S2 side of the eyeglass lens substrate 20. In reflectance measurement 3, the reflectance R Ｓ１ That is, in the reflectance measurement 3, the reflected light RL3 in FIG. 2 is measured, and the reflectance R Ｓ１ Similarly, in reflectance measurement 4, the reflectance R on the second main surface S2 side of the spectacle lens substrate 20 is measured at a plurality of angles in the range of θ from 0 to 60°. Ｓ２ That is, in the reflectance measurement 4, the reflected light RL4 in FIG. 2 is measured, and the reflectance R Ｓ２ (θ) is measured.

[0013] The reflectance measurements 1 to 4 can be performed by known methods. For example, the reflectance measurements 1 to 4 may be performed using a known reflectance measuring device, or may be calculated by performing an optical simulation based on the refractive index of the material constituting the eyeglass lens substrate and the refractive index of the material constituting the anti-reflection coating.

[0014] Furthermore, the reflectance measurements 1 to 4 are each performed at a plurality of angles θ in the range of 0 to 60°. That is, the reflectance measurements 1 to 4 are each performed at two or more angles in the range of θ in the range of 0 to 60°. As the angle θ for performing the reflectance measurements 1 to 4, it is preferable to select at least two angles in the range of 0 to 10°, and further to select at least one angle in the range of more than 10° and not more than 60°. It is more preferable to select at least 0°, 2°, 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, and 60° as the angle θ. The reflectance measurements 1 to 4 are each performed at the same value of θ. By performing the reflectance measurements 1 to 4 while changing the angle θ as described above, the reflectance on the first principal surface side of the eyeglass lens, the reflectance on the second principal surface side of the eyeglass lens, the reflectance on the first principal surface side of the eyeglass lens substrate, and the reflectance on the second principal surface side of the eyeglass lens substrate can be obtained at each angle θ.

[0015] [Transmittance Calculation Step] The spectacle lens evaluation method of the present disclosure includes a transmittance calculation step. In the transmittance calculation step, the transmittance T １ (θ) and the transmittance T ２ (θ) and the difference T ＡＲ (θ), and the transmittance T expressed by 100 and the above formula (2) ２ (θ) and the difference T ＩＤ (θ) is calculated using the formula (1) T １ (θ) = 100 - R １ (θ)-R ２ (θ) Formula (2) T ２ (θ) = 100 - R Ｓ１ (θ)-R Ｓ２ (θ) R in the above formula (1) and formula (2) １ (θ), R ２ (θ), R Ｓ１ (θ) and R Ｓ２ The values ​​obtained in the reflectance measurements 1 to 4 performed in the reflectance measurement step are used for (θ). １(θ) represents the transmittance of the spectacle lens at each of the angles θ. ２ (θ) represents the transmittance of the spectacle lens at each of the angles θ. １ (θ), transmittance T ２ (θ), T ＡＲ (θ) and T ＩＤ The unit of the value of (θ) is %.

[0016] Above T ＡＲ (θ) is the transmittance T １ From (θ), the transmittance T ２ (θ) is subtracted from the ＡＲ (θ) is calculated by the following formula (3): ＡＲ (θ) = T １ (θ)-T ２ (θ) where transmittance T １ The value of (θ) is generally determined by the function of the anti-reflection coating. ２ (θ) is larger than T ＡＲ (θ) generally takes a positive value. ＡＲ (θ) is understood to be the value of the transmittance improved by the anti-reflection film at each of the above angles θ.

[0017] Above T ＩＤ (θ) is calculated by the following formula (4): ＩＤ (θ) = 100 - T ２ (θ) Also, T calculated in the transmittance calculation step ＩＤ (θ) is understood to be the value of the transmittance improved by an ideal anti-reflection film that reduces the reflection generated by the spectacle lens substrate to zero at each of the above angles θ.

[0018] [Value X Calculation Step] The spectacle lens evaluation method of the present disclosure includes a value X calculation step. In the value X calculation step, the T ＡＲ (θ) and D Ｃ (θ) and M １ (θ) is calculated, and the M １(θ) to obtain the value X. That is, the value X is obtained by summing the reflectance measurements 1 to 4 above, １ , ..., and θ ｎ (n is a natural number of 2 or more), it can be calculated by the following formula (X1).

[0019]

[0020] Above D Ｃ (θ) represents the number of cone cells corresponding to the angle θ. Ｃ (θ) represents the number of cone cells of a wearer who responds to light in a direction parallel to the light incident on the spectacle lens from the angle θ when the optical axis of the eye of the wearer of the spectacle lens is aligned with the optical axis of the spectacle lens substrate. Ｃ (θ) will be explained with reference to the drawings.

[0021] Fig. 3 is a cross-sectional schematic diagram of eyeglasses using eyeglass lenses evaluated using the eyeglass lens evaluation method of the present disclosure when worn. Note that Fig. 3 omits the eyeglass frame and illustrates only one of the eyeglass lenses included in the eyeglasses. Fig. 3 is also a cross-sectional schematic diagram taken along a plane perpendicular to the height direction of the eyeglass wearer. In Fig. 3 , incident light L3 is incident on the eyeglass lens 10. The incident light L3 is incident perpendicular to the surface of the eyeglass lens 10 and is parallel to the normal to the tangent plane at the point where it intersects with the surface of the eyeglass lens. Note that the anti-reflection coating included in the eyeglass lens 10 is not shown in Fig. 3 .

[0022] Here, the optical axis of the wearer's eye 30 (shown by a dotted line in FIG. 3 ) coincides with the direction of incidence of the incident light L1. Note that FIG. 3 illustrates only the crystalline lens 32 and retina 34 of the eye 30, and does not show other components of the human eye. Such incident light L3 passes through the spectacle lens 10, enters the eye 30, and reaches area CA of the retina 34 through the crystalline lens 32. In the retina 34, cone cells are distributed in large numbers near the optical axis of the eye 30, and this area is shown as area CA in FIG. 3 . On the other hand, in the retina 34, rod cells are concentrated in areas other than area CA, and this area is shown as area RA in FIG. 3 .

[0023] Cone cells are generally responsible for color vision and vision in bright places, while rod cells are responsible for vision in dark places. Therefore, in bright places, light incident on area CA, such as incident light L3, is more easily perceived as a light stimulus. On the other hand, incident light L5 incident from an oblique direction relative to the optical axis of the eye 30 passes through the crystalline lens 32 and reaches area RA of the retina 34. Since incident light L5 from such a direction is sensed in area RA, where many rod cells are present, it tends to be less easily perceived as a light stimulus than incident light L3. Note that incident light L5 and incident light L4 are parallel. In other words, by measuring the reflectance of incident light L4 incident on the spectacle lens 10 at a predetermined angle relative to the optical axis of the spectacle lens 10, it is possible to evaluate the effect of incident light L5, which is light incident on the eye 30 through the spectacle lens 10 and which is incident at the same predetermined angle relative to the optical axis of the eye 30 as the incident light L4.

[0024] From the above, it can be said that the smaller the angle θ, the more easily light is incident on the area shown by area CA in Fig. 3 in bright light, and the more easily it is perceived as a light stimulus. That is, for light incident on the spectacle lens 10 from the angle θ, it enters the eye 30 at the angle θ with respect to the optical axis of the eye 30 and reaches the retina 34, so it can be said that the brightness of light that the wearer can perceive differs depending on the value of the angle θ, depending on the density of cone cells that react to light incident from the angle θ. Here, in the value X calculation step, D Ｃ (θ) and the above T ＡＲ It is believed that by multiplying this by (θ) and calculating the sum (value X), it is possible to evaluate the brightness of the field of view through the eyeglass lenses in a bright environment.

[0025] In addition, D Ｃ The specific values ​​for each angle θ are as shown in Table 1 below.

[0026]

[0027] Here, angles θ other than those shown in the table above Ｘ D in Ｃ The value of (θ) is the angle θ ＸD at the angle θ closest to Ｃ (θ) and the angle θ Ｘ D at the second closest angle θ Ｃ For example, if the angle θ is 6°, the closest angle θ in the table above is 5°, and the second closest angle θ is 10°. Ｃ (θ) value of 20000 and D at 10° Ｃ When linearly interpolated using the value of 5000 for (θ), the value is 17000 (pieces / mm ２ ) is calculated as shown in the above table. Ｃ (θ) corresponds to the number of cone cells in a typical retina of the human eye. The values ​​listed in the table above correspond to the density of cone cells on the temple side of the eye and are based on the 1935 study by Osterberg (Topography of the layer of rods and cones in the human retina, Volume 6 of Acta ophthalmologica: Supplementum, GA Osterberg, 1935).

[0028] [Value Y Calculation Step] The spectacle lens evaluation method of the present disclosure includes a value Y calculation step. In the value Y calculation step, the T ＩＤ (θ) and the above D Ｃ (θ) and M ２ (θ) is calculated, and the M ２ (θ) to obtain the value Y. That is, the value Y is obtained by summing the reflectance measurements 1 to 4 above, １ , ..., and θ ｎ (n is a natural number of 2 or more), it can be calculated by the following formula (Y1).

[0029]

[0030] Above D Ｃ (θ) is the same as that explained in the value X calculation step.

[0031] [Specific Parameter Calculation Step] The spectacle lens evaluation method of the present disclosure includes a specific parameter calculation step. In the specific parameter calculation step, a specific parameter is calculated by dividing the value X by the value Y. As described above, the T ＩＤ (θ) is understood to be the value of transmittance improved by an ideal anti-reflection coating, and is the T used to calculate the value X. ＡＲ (θ) is understood to be the value of transmittance improved by the anti-reflection coating. Therefore, the specific parameter (value X / value Y) can be said to be the improvement rate of transmittance improved by the anti-reflection coating, taking into account the characteristics of the human eye. Here, since the transmittance of eyeglass lens substrates is usually high, the performance of the anti-reflection coating can be said to have a significant impact on the brightness of the field of view through the eyeglass lens. Therefore, the specific parameter (value X / value Y) can be said to be an index of the brightness of the field of view through the eyeglass lens in a bright environment, as evaluated by the eyeglass lens evaluation method of the present disclosure.

[0032] The specific parameter takes a value between 0 and 1. It is considered that the closer the value of the specific parameter is to 1, the brighter the field of view through the eyeglass lens. Therefore, for example, by calculating the specific parameter for each of a plurality of eyeglass lenses, comparing and evaluating the specific parameters, and selecting eyeglass lenses that exhibit higher specific parameters, it is possible to provide eyeglass lenses that provide the user with a brighter field of view. The specific parameter may be multiplied by a predetermined coefficient. The predetermined coefficient can be set as appropriate, and examples include 0.01, 0.1, 10, 100, 1000, and 10000.

[0033] Some or all of the steps of the above-described spectacle lens evaluation method may be performed by a processing device, such as a known computer.

[0034] <Eyeglass Lens> The eyeglass lens used in the eyeglass lens evaluation method of the present disclosure has an eyeglass lens substrate and an anti-reflection coating. Figure 4 is a cross-sectional view of one embodiment of an eyeglass lens used in the eyeglass lens evaluation method of the present disclosure. The eyeglass lens 10 shown in Figure 4 includes, in this order, a first anti-reflection coating 18a, an eyeglass lens substrate 20, and a second anti-reflection coating 18b. The eyeglass lens substrate 20 has a first main surface and a second main surface, which are not shown in Figure 4. The eyeglass lens substrate 20 includes, in this order, a hard coat layer 16a, a primer layer 14a, a substrate 12, a primer layer 14b, and a hard coat layer 16b.

[0035] 4, the first antireflection film 18a and the second antireflection film 18b typically have a high refractive index layer and a low refractive index layer. The total number of high refractive index layers and low refractive index layers is preferably two or more, more preferably four or more, even more preferably six or more, and particularly preferably eight or more. There is no particular upper limit on the total number of high refractive index layers and low refractive index layers, but from the viewpoint of productivity, it is preferably 14 or less, more preferably 12 or less. Furthermore, the first antireflection film 18a may include layers other than the low refractive index layer and the high refractive index layer (for example, an antistatic layer, which will be described later).

[0036] In Fig. 4, the spectacle lens substrate 20 includes a primer layer 14a, a primer layer 14b, and a hard coat layer 16a and a hard coat layer 16b, but these components are optional and may be omitted. Also, in Fig. 4, the spectacle lens 10 includes a first antireflection coating 18a and a second antireflection coating 18b, but either the first antireflection coating 18a or the second antireflection coating 18b may be omitted. The spectacle lens 10 shown in Fig. 4 may have a water- and oil-repellent layer on the side of the first antireflection coating 18a opposite the substrate 12 side and on the side of the second antireflection coating 18b opposite the substrate 12 side.

[0037] Hereinafter, the configurations included in the spectacle lens subjected to the spectacle lens evaluation method of the present disclosure, and the configurations that may be included, will be described.

[0038] [Substrate] The substrate is a member that supports the anti-reflection film. The type of substrate is not particularly limited, and examples include ordinary substrates composed of plastic, inorganic glass, etc., with plastic substrates being preferred in terms of excellent handleability. The type of plastic (so-called resin) contained in the plastic substrate is not particularly limited, and examples include (meth)acrylic acid ester resins, thiourethane resins, allyl resins, episulfide resins, polycarbonates, urethane resins, polyesters, polystyrene, polyethersulfone, poly-4-methylpentene-1, and diethylene glycol bisallyl carbonate resins (CR-39). Of these, thiourethane resins, episulfide resins, and diethylene glycol bisallyl carbonate resins are preferred.

[0039] The type of plastic substrate is not particularly limited, but examples thereof include embodiments having a convex surface and a concave surface. More specifically, examples include a finished lens in which both the convex surface and the concave surface are optically finished and molded according to a desired power, a semi-finished lens in which only the convex surface is finished as an optical surface (spherical surface, rotationally symmetric aspherical surface, progressive surface, etc.), and a lens in which the concave surface of a semi-finished lens is processed and polished according to a wearer's prescription.

[0040] The thickness of the plastic substrate is not particularly limited, but is often about 1 to 30 mm from the viewpoint of ease of handling. The refractive index of the plastic substrate is not particularly limited, but is often 1.50 or higher, preferably 1.60 to 1.80, and more preferably 1.60 to 1.74. Furthermore, the plastic substrate does not have to be colorless as long as it is translucent, and may contain an ultraviolet absorber and a dye that absorbs light in a specific wavelength range from the ultraviolet to the infrared region. Furthermore, the plastic substrate may contain additives such as a bluing agent, a light stabilizer, and an antioxidant.

[0041] [Primer Layer] The spectacle lens may include a primer layer. The primer layer is preferably disposed between the substrate and the hard coat layer. When a primer layer is disposed between the substrate and the hard coat layer, it improves the adhesion of the hard coat layer to the substrate and improves the static load or impact strength of the spectacle lens having an anti-reflection film disposed on the hard coat layer. The material constituting the primer layer is not particularly limited, and known materials can be used, for example, resins are mainly used. The type of resin used is not particularly limited, and examples include polyurethane resins, epoxy resins, phenolic resins, polyimide resins, polyester resins, bismaleimide resins, and polyolefin resins, with polyurethane resins being preferred. The primer layer may also contain components other than the resin. Examples of the other components include oxide fine particles of at least one metal selected from Si, Al, Sn, Sb, Ta, Ce, La, Fe, Zn, W, Zr, In, and Ti, or composite oxide fine particles thereof, hydrolyzable silicon compounds and / or their hydrolyzed condensates, conductive fillers, and surfactants.

[0042] The method for forming the primer layer is not particularly limited, and known methods can be used, such as a method of applying a primer layer-forming composition containing a predetermined resin onto a substrate and, if necessary, performing a curing treatment to form a primer layer. The method for applying the primer layer-forming composition is not particularly limited, and examples thereof include the method exemplified by the method of applying a hard coat layer-forming composition to a substrate, which will be described later. The thickness of the primer layer is not particularly limited, but is preferably 0.3 to 2 μm.

[0043] [Hard Coat Layer] The eyeglass lens may include a hard coat layer. The hard coat layer is preferably disposed between the substrate and the anti-reflection film, and is a layer that imparts scratch resistance to the substrate. The hard coat layer preferably exhibits a pencil hardness of "H" or higher according to the test method defined in International Standard ISO 15184 and Japanese Industrial Standard JIS K5600, which was created based on this international standard.

[0044] As the hard coat layer, a known hard coat layer can be used, for example, an organic hard coat layer, an inorganic hard coat layer, or an organic-inorganic hybrid hard coat layer. For example, in the field of eyeglass lenses, an organic-inorganic hybrid hard coat layer is commonly used.

[0045] The hard coat layer preferably contains a polymer of a polymerizable monomer (a polymer obtained by polymerizing a polymerizable monomer) and / or a condensate of a hydrolyzable organosilicon compound. The polymerizable monomer is not particularly limited, but examples thereof include (meth)acrylates having at least one group selected from the group consisting of phosphate groups and sulfonic acid groups, silsesquioxanes having radical polymerizable groups, polyfunctional acrylates, compounds having multiple epoxy groups, and silsesquioxane compounds having oxetanyl groups. Note that (meth)acrylate refers to acrylate or methacrylate. The hydrolyzable organosilicon compound is not particularly limited, but examples thereof include organosilicon compounds having epoxy groups.

[0046] The hard coat layer may also contain inorganic components such as metal oxide fine particles. The type of metal oxide fine particles is not particularly limited, and examples include known metal oxide fine particles. Examples of metal oxide fine particles include fine particles of at least one metal oxide selected from Si, Al, Sn, Sb, Ta, Ce, La, Fe, Zn, W, Zr, In, and Ti. Among these, in terms of ease of handling, metal oxide fine particles are preferably fine particles of oxides containing Si (silicon oxide fine particles), oxides containing Sn (tin oxide fine particles), oxides containing Zr (zirconium oxide fine particles), or oxides containing Ti (titanium oxide fine particles). The metal oxide fine particles may contain only one of the above-mentioned metals (metal atoms) or two or more metals (metal atoms). Although Si (silicon) is sometimes classified as a semimetal, in the present disclosure, Si is considered to be included in the metals.

[0047] The hard coat layer is preferably formed using a hard coat layer-forming composition containing a polymerizable monomer. The hard coat layer-forming composition may contain, in addition to the polymerizable monomer, the metal oxide fine particles, other components, and a solvent. Examples of other components include a radical polymerization initiator, a cationic polymerization initiator, and a curing catalyst. Other components may also include various additives, such as UV absorbers, antioxidants, coating modifiers, light stabilizers, antioxidants, color inhibitors, dyes, fillers, and internal mold release agents, which are added as needed. The solvent may be water or an organic solvent. The type of organic solvent is not particularly limited, and examples include alcohol-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, hydrocarbon-based solvents, halogenated hydrocarbon-based solvents, amide-based solvents, sulfone-based solvents, and sulfoxide-based solvents.

[0048] A method for forming a hard coat layer using a hard coat layer-forming composition includes applying the hard coat layer-forming composition to a substrate (or a primer layer) to form a coating film, and then subjecting the coating film to a curing treatment such as light irradiation treatment and heat treatment. As the curing treatment, either one of light irradiation treatment and heat treatment may be performed, or both may be performed. When both are performed, the light irradiation treatment and heat treatment may be performed simultaneously, or one may be performed first and then the other. After forming the coating film, a drying treatment such as heat treatment may be performed, if necessary, to remove the solvent from the coating film.

[0049] The method for applying the composition for forming a hard coat layer is not particularly limited, and includes known methods (e.g., dipping coating, spin coating, spray coating, inkjet coating, and flow coating). The thickness of the coating film to be formed is not particularly limited, and a thickness that will result in a predetermined hard coat layer thickness is appropriately selected.

[0050] The conditions for the light irradiation treatment are not particularly limited, and appropriate conditions are selected depending on the type of polymerization initiator used. The type of light used for light irradiation is not particularly limited, but examples include ultraviolet light and visible light. Examples of light sources include high-pressure mercury lamps. The cumulative light amount used for light irradiation is not particularly limited, but from the viewpoints of productivity and curability of the coating film, it is preferred to use a light amount of 100 to 3000 mJ / cm. ２ is preferred, and 100 to 2000 mJ / cm ２ The conditions for the heat treatment are not particularly limited, and the optimum conditions are selected depending on the type of polymerization initiator used. The heating temperature is preferably 30 to 100°C, and the heating time is preferably 5 to 360 minutes.

[0051] The thickness of the hard coat layer is not particularly limited, but is preferably 1 μm or more, more preferably 3 μm or more, and even more preferably 10 μm or more. The upper limit of the thickness can be, for example, 30 μm or less. The thickness is an average thickness, and the measurement method is to measure the thickness at any five points on the hard coat layer and calculate the arithmetic average.

[0052] The hard coat layer may contain additives such as a bluing agent, a light stabilizer, and an antioxidant.

[0053] [Anti-reflection film] The spectacle lens includes an anti-reflection film. An anti-reflection film is a layer that has the function of preventing reflection of incident light. Specifically, an anti-reflection film has low reflectance characteristics (broadband low reflectance characteristics) over the entire visible range of 380 to 780 nm.

[0054] The anti-reflection film preferably includes a high refractive index layer and a low refractive index layer. In the anti-reflection film, the high refractive index layer and the low refractive index layer are preferably arranged alternately. That is, when the anti-reflection film includes two high refractive index layers and two low refractive index layers, it is preferable that a low refractive index layer is arranged between two high refractive index layers, and a high refractive index layer is arranged between two low refractive index layers. As will be described later, an antistatic layer (e.g., SnO ２Indium tin oxide (ITO) is indium tin oxide, and indium oxide (In ２ O ３ ) and tin oxide (SnO ２ ) is a mixture of

[0055] The high refractive index layer is preferably a layer having a refractive index of 1.60 or more. The high refractive index layer preferably contains at least one oxide selected from the group consisting of titanium, zirconium, aluminum, niobium, tantalum, and lanthanum. Among these, the high refractive index layer is preferably made of zirconium dioxide (ZrO ２ The high refractive index layer may contain two or more materials.

[0056] The low refractive index layer is preferably a layer having a refractive index of less than 1.60. The low refractive index layer preferably contains at least one selected from the group consisting of silicon oxide, calcium fluoride, and magnesium fluoride. In particular, the low refractive index layer preferably contains silicon dioxide (SiO ２ The low refractive index layer may contain two or more materials.

[0057] The total number of high refractive index layers and low refractive index layers in the antireflection film and preferred embodiments thereof are as described above.

[0058] In the antireflection film, the layer disposed closest to the plastic substrate may be a low refractive index layer or a high refractive index layer.

[0059] For example, the thickness of each of the high refractive index layers is preferably 5 to 200 nm, more preferably 5 to 150 nm, and even more preferably 8 to 100 nm, and the thickness of each of the low refractive index layers is preferably 10 to 500 nm, more preferably 15 to 450 nm, and even more preferably 20 to 200 nm.

[0060] Preferred embodiments of the antireflection film are exemplified below. In the embodiment (embodiment 1) in which the antireflection film is composed of, in order from the substrate side, a first high refractive index layer, a first low refractive index layer, a second high refractive index layer, a second low refractive index layer, a third high refractive index layer, a third low refractive index layer, a fourth high refractive index layer, and a fourth low refractive index layer, each layer is preferably in the following embodiment. First high refractive index layer: Material: ZrO ２ , thickness: 5 to 15 nm First low refractive index layer Material: SiO ２ , Thickness: 40 to 60 nm Second high refractive index layer Material: ZrO ２ , Thickness: 10 to 20 nm Second low refractive index layer Material: SiO ２ , Thickness: 100 to 200 nm Third high refractive index layer Material: ZrO ２ , Thickness: 5 to 15 nm Third low refractive index layer Material: SiO ２ , Thickness: 20 to 40 nm Fourth high refractive index layer Material: ZrO ２ , Thickness: 40 to 80 nm Fourth low refractive index layer Material: SiO ２ , thickness: 70 to 110 nm

[0061] In the case of an embodiment (embodiment 2) in which the antireflection film is composed of, in order from the substrate side, a first high refractive index layer, a first low refractive index layer, a second high refractive index layer, and a second low refractive index layer, each layer is preferably in the following embodiment: First high refractive index layer: Material: ZrO ２ , Thickness: 10 to 20 nm First low refractive index layer Material: SiO ２ , Thickness: 10 to 30 nm Second high refractive index layer Material: ZrO ２ , Thickness: 60 to 100 nm Second low refractive index layer Material: SiO ２ , thickness: 60 to 100 nm

[0062] The method for producing the anti-reflection film is not particularly limited, and examples thereof include dry methods such as vacuum deposition, sputtering, ion plating, ion beam assisted deposition, and CVD.

[0063] The anti-reflection film contains, in addition to the high refractive index layer and the low refractive index layer, SnO ２ The layer may further include a SnO layer or an ITO layer. ２ The SnO layer and the ITO layer can function as an antistatic layer.２ The positions of the SnO layer and the ITO layer are not particularly limited, and may be between the high refractive index layer and the low refractive index layer. ２ The thickness of the ITO layer or the ITO layer can be appropriately set, but is preferably 3 to 20 nm, more preferably 3 to 10 nm. In addition, when an antistatic layer is provided in the above-mentioned embodiment 1, it is preferable to provide the antistatic layer between the fourth high refractive index layer and the fourth low refractive index layer, and a preferable material for the antistatic layer is SnO. ２ and the preferred thickness is 3 to 10 nm.

[0064] [Water- and oil-repellent layer] The eyeglass lens may include a water- and oil-repellent layer. In particular, it is preferable that the eyeglass lens has a water- and oil-repellent layer as the outermost layer. The water- and oil-repellent layer reduces the surface energy of the eyeglass lens, improving the anti-fouling function of the eyeglass lens and improving the slipperiness of the eyeglass lens surface, which in turn improves the abrasion resistance of the eyeglass lens.

[0065] The material constituting the water- and oil-repellent layer is not particularly limited, and examples thereof include fluorine-containing compounds (compounds containing fluorine atoms) and silicon-containing compounds (compounds containing silicon atoms). Among these, the water- and oil-repellent layer preferably contains a fluorine-containing compound, and more preferably contains at least one selected from the group consisting of fluorine-substituted alkyl group-containing organosilicon compounds, their hydrolysates, and their hydrolyzed condensates. The material constituting the water- and oil-repellent layer may be used alone or in combination of two or more.

[0066] The organosilicon compound containing fluorine-substituted alkyl group is the organosilicon compound that contains alkyl group in which part or all of hydrogen atom is replaced by fluorine atom, and has hydrolyzable group.Here, the hydrolyzable group is the group that is directly bonded to silicon atom and can proceed hydrolysis reaction and condensation reaction, for example, alkoxy group, halogen atom, acyloxy group, alkenyloxy group and isocyanate group.It should be noted that when a plurality of hydrolyzable groups are directly bonded to one silicon atom, they can be the same or different.

[0067] The hydrolyzate of a fluorine-substituted alkyl group-containing organosilicon compound refers to a compound obtained by hydrolyzing the hydrolyzable groups in a fluorine-substituted alkyl group-containing organosilicon compound. The hydrolyzate may be one in which all of the hydrolyzable groups are hydrolyzed (complete hydrolyzate) or one in which only a portion of the hydrolyzable groups are hydrolyzed (partial hydrolyzate). In other words, the hydrolyzate may be a complete hydrolyzate, a partial hydrolyzate, or a mixture thereof. The hydrolyzed condensate of a fluorine-substituted alkyl group-containing organosilicon compound refers to a compound obtained by hydrolyzing the hydrolyzable groups in a fluorine-substituted alkyl group-containing organosilicon compound and condensing the resulting hydrolyzate. The hydrolyzed condensate may be one in which all of the hydrolyzable groups are hydrolyzed and the hydrolyzate is completely condensed (complete hydrolyzed condensate), or one in which only a portion of the hydrolyzable groups are hydrolyzed and a portion of the hydrolyzate is condensed (partial hydrolyzed condensate). In other words, the hydrolyzed condensate may be a complete hydrolyzed condensate, a partial hydrolyzed condensate, or a mixture thereof.

[0068] The method for forming the water- and oil-repellent layer is not particularly limited and can be selected as desired depending on the materials used, the desired performance, thickness, etc. Examples include a method in which a water- and oil-repellent layer-forming composition containing a fluorine-substituted alkyl group-containing organosilicon compound is applied to a substrate and cured as needed, and a dry method. Coating methods include, for example, dip coating, roll coating, bar coating, spin coating, spray coating, die coating, and gravure coating. Curing treatments include, for example, light irradiation treatment, heat treatment, and water vapor contact treatment. Water vapor contact treatments include, for example, contact with air controlled at a humidity of 50 to 90% RH. The above curing treatments may be performed in combination. Examples of dry methods include the same methods as those used for the antireflective coating described above.

[0069] The thickness of the water- and oil-repellent layer of the spectacle lens is not particularly limited, but is preferably 5 to 35 nm. If the thickness is within the above range, the spectacle lens will have excellent water- and oil-repellent properties.

[0070] The spectacle lenses evaluated by the spectacle lens evaluation method of the present disclosure are suitable for use as lenses for spectacle lenses. Examples of spectacle lenses include spectacles having a known spectacle frame and spectacle lenses, and examples of spectacle frames include those having a pair of lens frames on which spectacle lenses for the right eye and the left eye are respectively attached, and temples for hanging the spectacle frame on the wearer's ears.

[0071] The above-mentioned embodiments will be explained in more detail below with reference to examples and comparative examples, but the present disclosure is not limited to these examples in any way.

[0072] <Simulation> The characteristics of the eyeglass lenses having the configurations of the examples were evaluated by software simulation. More specifically, the eyeglass lenses having the configurations of the examples shown below were constructed on software (optical thin film design software ThinFilmView (Nary Software), hereinafter also referred to as "TFV"), and the reflectance at a predetermined angle of incidence θ was calculated. The refractive index of air was set to 1.00 in the calculation.

[0073] Spectacle lenses having the configurations shown in Table 2 below were constructed on the TFV. The refractive indices shown in Table 2 below are refractive indices at 507 nm.

[0074]

[0075] The reflectance measurement process described above was carried out at angles of θ=0°, 2°, 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, and 60°. Specifically, for the spectacle lens having the above configuration, the reflectance (reflectance R １ (θ) and reflectance R ２ (θ)) was calculated using TFV, and reflectance measurements 1 and 2 were performed. Next, a model of only the substrate was constructed, and the reflectance (reflectance R Ｓ１ (θ) and reflectance R Ｓ２ (θ)) was calculated using TFV, and reflectance measurements 3 and 4 were performed.

[0076] Subsequently, the transmittance calculation step was carried out according to the procedure described above. Specifically, the reflectance (reflectance R １ (θ) and reflectance R ２ (θ) and reflectance R Ｓ１ (θ) and reflectance R Ｓ２ (θ)), T １ (θ) and T ２ (θ) is calculated, and T ＡＲ (θ) and T ＩＤ (θ) was calculated. Next, the value X calculation step and the value Y calculation step were performed in the above-described procedure, and further, the specific parameter calculation step was performed to calculate the specific parameter. Table 3 below lists the specific parameter values ​​multiplied by 100. Note that the D Ｃ For (θ), the values ​​shown in Table 1 above were used.

[0077] Furthermore, as Example 5, specific parameters were calculated using the same procedure as above for a configuration including only the substrate. Table 3 below lists values ​​obtained by multiplying the calculated specific parameters by 100.

[0078] <Evaluation> In a daylight environment, subjects were asked to evaluate the brightness of the field of view through the spectacle lenses. More specifically, subjects were asked to evaluate the brightness of the field of view through the spectacle lenses using the following procedure. First, the external light environment outside a window was observed from indoors through the spectacle lenses of Examples 3, 4, and 5. When observing the external light environment through each spectacle lens, the spectacle lens that appeared to be the brightest was rated as A, the spectacle lens that appeared to be the second brightest as B, and the spectacle lens that appeared to be the third brightest as C. There were three subjects. The evaluation results are shown in Table 3.

[0079]

[0080] From the results shown in Table 3, it was confirmed that the ranking of the values ​​obtained by multiplying the specific parameter by 100 corresponds to the ranking of spectacle lenses that are perceived as bright. In other words, it was confirmed that the brightness of the field of view through spectacle lenses including an anti-reflection coating in a bright environment can be evaluated based on the magnitude of the specific parameter calculated using the spectacle lens evaluation method of the present disclosure.

Claims

1. A method for evaluating a spectacle lens comprising a spectacle lens substrate having a first principal surface and a second principal surface, and an anti-reflection coating disposed on at least one of the first principal surface and the second principal surface of the spectacle lens substrate, the method comprising the steps of: performing reflectance measurement 1, reflectance measurement 2, reflectance measurement 3, and reflectance measurement 4 at a plurality of angles in the range of 0 to 60 degrees, where θ is the angle formed between the optical axis of the spectacle lens substrate and incident light incident from the first principal surface side; and measuring a transmittance T １ (θ) and the transmittance T ２ (θ) and the difference T ＡＲ (θ), and the transmittance T ２ (θ) and the difference T ＩＤ (θ), and calculating the T ＡＲ (θ) and the following D Ｃ (θ) and M １ (θ) is calculated, and the M １ (θ) to obtain a value X; and ＩＤ (θ) and the D Ｃ (θ) and M ２ (θ) is calculated, and the M ２ (θ) to obtain a value Y, and calculating a specific parameter by dividing the value X by the value Y. Reflectance measurement 1: Incident light is incident from the first principal surface side of the spectacle lens at the angle θ, and the reflectance R on the first principal surface side of the spectacle lens is measured. １ Reflectance measurement 2: Incident light is incident from the first principal surface side of the spectacle lens at the angle θ, and the reflectance R (θ) on the second principal surface side of the spectacle lens is measured. ２ Reflectance measurement 3: Incident light is incident from the first principal surface side of the eyeglass lens substrate at the angle θ, and the reflectance R (θ) on the first principal surface side of the eyeglass lens substrate is measured. Ｓ１ Reflectance measurement 4: Incident light is incident from the first principal surface side of the eyeglass lens substrate at the angle θ, and the reflectance R (θ) on the second principal surface side of the eyeglass lens substrate is measured. Ｓ２ (θ) is measured using the equation (1) T １ (θ) = 100 - R １ (θ)-R ２ (θ) Formula (2) T ２ (θ) = 100 - R Ｓ１ (θ)-R Ｓ２ (θ) Said D Ｃ (θ) represents the number of cone cells corresponding to the angle θ.

2. The method for evaluating a spectacle lens according to claim 1, wherein the anti-reflection film is disposed on the first principal surface and the second principal surface of the spectacle lens substrate.

3. The method for evaluating eyeglass lenses according to claim 1 or 2, wherein at least two angles are selected in the range of 0 to 10 degrees as the angle θ, and at least one angle is selected in the range of more than 10 degrees and not more than 60 degrees.

4. The method for evaluating a spectacle lens according to any one of claims 1 to 3, wherein the angle θ is selected from the group consisting of at least 0°, 2°, 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, and 60°.

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