Filter member and lens

Abstract

To improve the appearance of both a display and an object.SOLUTION: A filter member included in a member worn by a user comprises a base material and one or more types of absorption dyes dispersed in the base material. The transmission spectrum of the filter member includes: a first valley where a first minimum wavelength is located within a range A1 of 400nm or more and 450nm or less; a second valley where a second minimum wavelength is located within a range A2 of 540nm or more and 600nm or less; and a third valley where a third minimum wavelength is located within a range A3 of 680nm or more and 800nm or less. The maximum value of transmittance in a range B1 of 350nm or more and 400nm or less is at least 2.5 times the transmittance at a first peak wavelength. The maximum value of transmittance in a range B2 of 450nm or more and 540nm or less is at least 3 times the transmittance at a second peak wavelength. The maximum value of transmittance in a range B3 of 600nm or more and 680nm or less is at least 1.6 times the transmittance at a third peak wavelength.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a filter member and a lens.

Background Art

[0002] Patent Document 1 discloses a color adjustment filter for a display. The color adjustment filter adjusts the color tone of the display by containing an absorption dye.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a filter member and a lens that can improve the visibility of both a display and an object.

Means for Solving the Problems

[0005] The filter member according to one aspect of the present invention is a filter member provided in a member worn by a user, and includes a base material and one or more absorption dyes dispersed in the base material. The transmission spectrum of the filter member has a first valley in which a first minimum wavelength is located within a range of 400 nm or more and 450 nm or less, a second valley in which a second minimum wavelength is located within a range of 540 nm or more and 600 nm or less, and a third valley in which a third minimum wavelength is located within a range of 680 nm or more and 800 nm or less. The maximum value of the transmittance of the filter member within a range of 350 nm or more and 400 nm or less is 2.5 times or more the transmittance of the filter member at the first minimum wavelength, the maximum value of the transmittance of the filter member within a range of 450 nm or more and 540 nm or less is 3 times or more the transmittance of the filter member at the second minimum wavelength, and the maximum value of the transmittance of the filter member within a range of 600 nm or more and 680 nm or less is 1.6 times or more the transmittance of the filter member at the third minimum wavelength.

[0006] The lens according to one aspect of the present invention is a lens for glasses, sunglasses, or goggles including the filter member according to the above aspect.

Advantages of the Invention

[0007] According to the filter member and the lens of the present invention, it is possible to improve the visibility of both the display and the object.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6A

Figure 6B

Figure 7A

Figure 7B

Figure 8A

Figure 8B

Figure 9

DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, the filter member and the lens according to the embodiment of the present invention will be described in detail with reference to the drawings. Note that each of the embodiments described below shows a specific example of the present invention. Therefore, the numerical values, shapes, materials, components, arrangements and connection forms of the components, steps, order of steps, etc. shown in the following embodiments are merely examples and are not intended to limit the present invention. Therefore, among the components in the following embodiments, the components not described in the independent claims are described as optional components.

[0010] Also, each figure is a schematic diagram and is not necessarily drawn precisely. Therefore, for example, the scales in each figure do not necessarily match. Also, in each figure, substantially the same configuration is denoted by the same reference numeral, and overlapping explanations are omitted or simplified.

[0011] In addition, in this specification, terms indicating the relationship between elements, terms indicating the shape of elements, and numerical ranges are not expressions representing only strict meanings, but are expressions meaning substantially equivalent ranges, for example, including differences of about several percent. Also, when used together with a numerical value, "about" means a range of ±1% of the numerical value, but in some cases, it may mean a range of ±2%, ±3%, or ±5%.

[0012] In addition, in this specification, ordinal numbers such as "first" and "second" do not mean the number or order of components, unless otherwise specified, but are used for the purpose of avoiding confusion and distinguishing between components of the same type.

[0013] (Embodiment) [Filter Member and Lens] First, the configuration of the filter member and lens according to the embodiment will be described with reference to FIGS. 1 and 2.

[0014] FIG. 1 is an external perspective view of glasses 1 including a lens 10 having a filter member according to the present embodiment, and FIG. 2 is a diagram showing the configuration of a work system 100 including the lens 10 according to the present embodiment.

[0015] The glasses 1 shown in FIG. 1 include two lenses 10. The two lenses 10 are a left-eye lens and a right-eye lens, respectively. The optical characteristics of the two lenses 10 are the same as each other. For example, when transmitting incident light, the lens 10 includes a filter member that absorbs a part of the light and emits it. The lens 10 may not have the functions of focusing and diverging light. The specific configuration of the filter member included in the lens 10 will be described later.

[0016] The glasses 1 are an example of a member worn by the user U. Specifically, the glasses 1 are glasses for the work system 100 as shown in FIG. 2. That is, the glasses 1 are an example of a wearable product used, for example, when viewing the display 110. Alternatively, the glasses 1 may be glasses for vision correction or so-called novelty glasses.

[0017] The work system 100 shown in FIG. 2 is a system for causing the user U to perform a predetermined work. The predetermined work is work using the display 110. Specifically, the predetermined work is so-called desk work, play such as video games, e-Sports, etc. Alternatively, the predetermined work may be creation or editing of content such as documents, illustrations, images, videos, or office work. Alternatively, the predetermined work may be viewing or watching images or moving images such as photos.

[0018] As shown in FIG. 2, the work system 100 includes a lens 10, a display 110, and a lighting device 120. The lens 10 is a lens for glasses, but may be a lens for sunglasses or goggles. Specifically, the lens 10 is used for the glasses 1 worn by the user U. The work system 100 is constructed, for example, in an indoor space where sunlight (natural light) enters through a window. In the indoor space, there are arranged foliage plants 130 and furniture and equipment (not shown).

[0019] The display 110 is a display device that displays images or videos. The display 110 is, for example, a liquid crystal display device or an organic EL (Electroluminescence) display device. A liquid crystal display device generally includes a light source that emits white light. The light source includes, for example, a white LED (Light Emitting Diode). The white LED includes, for example, a blue LED and a yellow phosphor. The yellow phosphor emits yellow light by wavelength-converting a part of the blue light emitted from the blue LED. The combined light of the blue light that has not been wavelength-converted and the yellow light becomes white light. Note that the display 110 may be a display device including light-emitting elements corresponding to each of RGB.

[0020] The lighting device 120 is a device that illuminates an indoor space. As shown in FIG. 2, the lighting device 120 is, for example, a ceiling light attached to the ceiling, and emits white light toward the floor surface (downward). The lighting device 120 may be a downlight, a spotlight, or a lighting device installed on a wall or a floor.

[0021] The lighting device 120 includes, for example, white LEDs. The white LED includes a blue LED and a yellow phosphor. The yellow phosphor emits yellow light by wavelength-converting a part of the blue light emitted from the blue LED. The combined light of the blue light that has not been wavelength-converted and the yellow light becomes white light.

[0022] The user U works in an illumination environment by the white light from the lighting device 120 and / or in an illumination environment by the sunlight incident from the window. The user U may look at the display 110 or may look at an object other than the display 110, such as documents placed on a desk or the potted plant 130. When looking at the display 110, light emitted from the display 110 enters the user U's eyes through the glasses 1 (lens 10). When looking at an object other than the display 110, reflected light of the white light from the lighting device 120 and / or the sunlight by the object enters the user U's eyes through the glasses 1.

[0023] In this way, the object seen by the user U changes according to the situation, and the light incident on the eyes of the user U also changes. Therefore, it is required that the filter member not only improves the appearance of the display 110 but also improves the appearance of objects other than the display 110. Note that improving the appearance of the display 110 means expanding the color gamut of the display 110. Also, improving the appearance of objects other than the display 110 means enhancing the color of the object and / or enhancing the whiteness of a white object by increasing the color temperature of white.

[0024] The vividness of color can be represented by the FCI (Feeling of Contrast Index) of the transmitted light when equal-energy white light passes through the filter member. The FCI is an index indicating that the higher the numerical value, the higher the color reproducibility and the more vividly the color of the object can be reproduced. The whiteness can be represented by the chroma value of the transmitted light when equal-energy white light passes through the filter member. The chroma value can be used as an index indicating that the lower the numerical value, the whiter, that is, the higher the whiteness of a white object.

[0025] In FIGS. 1 and 2, the glasses 1 including the lens 10 are illustrated as an example of a wearable product, but the wearable product including the lens 10 is not limited to the glasses 1. For example, the wearable product including the lens 10 may be sunglasses or goggles. The wearable product including the lens 10 may be a dedicated product for a game system or a general-purpose product used in daily life other than games.

[0026] Here, the work system 100 constructed in the indoor space is shown, but it is not limited thereto. The display 110 may be attached to the outer wall of a building or the like, and the user U may be a person who is outside and not performing any particular work.

[0027] [Filter member] Subsequently, the specific configuration of the filter member included in the lens 10 will be described.

[0028] In addition, in this embodiment, the lens 10 is the filter member itself, but is not limited thereto. The lens 10 may include a filter member and a functional film (for example, a protective film) provided on the surface of the filter member. Hereinafter, the case where the lens 10 is the filter member itself will be described as an example.

[0029] As shown in FIG. 1, the filter member (lens 10) includes a base material 11 and one or more absorption dyes 12 dispersed in the base material 11. In FIG. 1, a partial cross section of the filter member is enlarged and schematically shown.

[0030] The base material 11 is a plate-shaped member having translucency. The base material 11 is, for example, a resin base material formed by molding a transparent resin material into a predetermined shape. Specifically, the base material 11 contains a polycarbonate resin or an acrylic resin as a main component. Note that "containing as a main component" means that the proportion (mass %) of the mass of the polycarbonate resin or the acrylic resin in the total mass of the base material 11 exceeds 50%. In this embodiment, the base material 11 is substantially composed of a polycarbonate resin or an acrylic resin. The resin material used for forming the base material 11 may be an epoxy resin, a urethane resin, a polysilazane, a siloxane, an allyl diglycol carbonate (CR-39), or a polysiloxane composite acrylic resin.

[0031] The plate thickness of the base material 11 is, for example, 1 mm or more and 3 mm or less. The base material 11 may be a flat plate, or may be a curved plate having a convex surface or a concave surface. For example, the base material 11 may have a shape that realizes a lens function of condensing or diffusing light, such as a convex lens or a concave lens. That is, the plate thickness of the base material 11 may not be uniform in the plane and may vary depending on the part. The size and shape of the base material 11 are, for example, the size and shape suitable for glasses 1 that can be worn by a person.

[0032] The absorption dye 12 is a dye material that selectively absorbs light in a predetermined wavelength band. Specific examples of the absorption spectrum of the absorption dye 12 will be described later.

[0033] The absorption dye 12 is, for example, evenly dispersed inside the base material 11. Specifically, the absorption dye 12 is evenly dispersed throughout the thickness direction and the surface direction of the base material 11. Note that the absorption dye 12 may be dispersed only in a partial region inside the base material 11. For example, when the main surface of the base material 11 is viewed from the front, the absorption dye 12 may be dispersed only in the central region of the base material 11. Alternatively, the absorption dye 12 may be dispersed only in the surface layer portion of one surface in the thickness direction of the base material 11.

[0034] As the absorption dye 12, for example, merocyanine dyes, phthalocyanine dyes, porphyrin dyes, methine dyes, or the like can be used. Here, the A-based dye is a dye having A as the basic skeleton (parent structure). By introducing various substituents to the basic skeleton of the dye, it becomes possible to adjust the absorption wavelength and / or absorbance. As a result, the absorption dye 12 having a desired absorption spectrum can be realized.

[0035] In the present embodiment, the filter member contains a plurality of types of absorption dyes 12. By adjusting the type, number, content, mixing ratio, etc. of the absorption dye 12, the optical characteristics (transmission spectrum) of the filter member can be adjusted.

[0036] [Transmission Spectrum] Next, the transmission spectrum of the filter member will be described together with specific examples.

[0037] FIG. 3 is a diagram showing the transmission characteristics of the filter members according to Examples 1 and 2. In FIG. 3, the horizontal axis represents the wavelength (unit: nm), and the vertical axis represents the transmittance (unit: %).

[0038] The transmittance spectra of the filter members according to Examples 1 and 2 include four deep valleys in transmittance. The transmittance spectra of the filter members include peaks in transmittance between the four valleys. In this specification, the term "deep valley" means a valley where the transmittance is less than 50%. Hereinafter, a deep valley in transmittance will be referred to as a "valley in transmittance" or simply a "valley". Further, in this specification, the term "big peak" means a peak where the transmittance is 50% or more. Hereinafter, a big peak in transmittance will be referred to as a "peak in transmittance" or simply a "peak".

[0039] Specifically, as shown in FIG. 3, the transmittance spectra of the filter members include valleys in transmittance (the first valley V1, the second valley V2, and the third valley V3) in three ranges (wavelength bands) A1, A2, and A3, respectively. These first valley V1, second valley V2, and third valley V3 are formed due to the absorption spectra of one or more absorption dyes contained in the filter member.

[0040] Specifically, the range A1 is in the range of 400 nm or more and 450 nm or less, and the minimum wavelength λ1 of the first valley V1 is included within the range A1. The minimum wavelength is the wavelength at which the transmittance becomes minimum within a predetermined range (for example, the range A1). The transmittance at the minimum wavelength λ1 is, for example, 10% or more and 20% or less. The transmittance at the minimum wavelength λ1 may be 13% or more and may be 17% or less.

[0041] The full width at half maximum of the first valley V1 is 50 nm or less, but may be 40 nm or less, may be 30 nm or less, or may be 20 nm or less. The full width at half maximum of the first valley V1 is, for example, 10 nm or more, but is not limited thereto. The full width at half maximum of a valley corresponds to the width of the wavelength at the median value between the baseline of the valley and the minimum value in the transmittance spectrum. The baseline of the valley can be regarded as the larger value of the maximum value of the transmittance of the peak on the short wavelength side of the valley and the maximum value of the transmittance of the peak on the long wavelength side.

[0042] Range A2 is in the range of 540 nm or more and 600 nm or less, and the minimum wavelength λ2 of the second valley V2 is included within range A2. The transmittance at the minimum wavelength λ2 is, for example, 10% or more and 30% or less. Note that the transmittance at the minimum wavelength λ2 may be 15% or more, or may be 20% or more. Also, the transmittance at the minimum wavelength λ2 may be 25% or less, or may be 20% or less.

[0043] The full width at half maximum of the second valley V2 is 60 nm or less, but may be 50 nm or less, may be 40 nm or less, may be 30 nm or less, or may be 20 nm or less. The full width at half maximum of the second valley V2 is, for example, 10 nm or more, but is not limited thereto.

[0044] Range A3 is in the range of 680 nm or more and 800 nm or less, and the minimum wavelength λ3 of the third valley V3 is included. The transmittance at the minimum wavelength λ3 is, for example, 30% or more and 60% or less. Note that the transmittance at the minimum wavelength λ3 may be 40% or more, or may be 50% or more. Also, the transmittance at the minimum wavelength λ3 may be 50% or less, or may be 40% or less.

[0045] The full width at half maximum of the third valley V3 is 60 nm or less, but may be 50 nm or less, may be 40 nm or less, may be 30 nm or less, or may be 20 nm or less. The full width at half maximum of the third valley V3 is 10 nm or more, but is not limited thereto.

[0046] Also, in the range of wavelengths shorter than range A1, a fourth valley V4 is included. The fourth valley V4 is formed due to the transmittance spectrum of the base material 11. Note that the fourth valley V4 may also be formed due to the absorption spectrum of the absorption dye. In the fourth valley V4, for example, the transmittance becomes substantially 0% at 380 nm.

[0047] Also, as shown in FIG. 3, the transmittance spectrum of the filter member includes four peaks P1, P2, P3, and P4. The peak wavelength λa of peak P1 is located on the shorter wavelength side than the minimum wavelength λ1 of the first valley V1. Note that the peak wavelength is the wavelength at which the transmittance becomes maximum within a predetermined range. The peak wavelength λb of peak P2 is located between the minimum wavelength λ1 of the first valley V1 and the minimum wavelength λ2 of the second valley V2. The peak wavelength λc of peak P3 is located between the minimum wavelength λ2 of the second valley V2 and the minimum wavelength λ3 of the third valley V3. The peak wavelength λd of peak P4 is located on the longer wavelength side than the minimum wavelength λ4 of the third valley V3.

[0048] Also, the maximum value of the transmittance within range B1 is 2.5 times or more the transmittance at the minimum wavelength λ1. Range B1 is in the range of 350 nm or more and 400 nm or less. Note that the maximum value of the transmittance within range B1 may be 3 times or more, 3.5 times or more, 4 times or more, 4.5 times or more, or 5 times or more the transmittance at the minimum wavelength λ1. The maximum value of the transmittance within range B1 is 50% or more, but may be 60% or more, or 70% or more. The peak wavelength λa of peak P1 may be included within range B1.

[0049] The maximum value of the transmittance within range B2 is 3 times or more the transmittance at the minimum wavelength λ2. Range B2 is in the range of 450 nm or more and 540 nm or less. Note that the maximum value of the transmittance within range B2 may be 3.5 times or more, 4 times or more, 4.5 times or more, or 5 times or more the transmittance at the minimum wavelength λ2. The maximum value of the transmittance within range B2 is 70% or more, but may be 80% or more, or 90% or more.

[0050] The maximum value of the transmittance within range B3 is 1.6 times or more the transmittance at the minimum wavelength λ3. Range B3 is in the range of 600 nm or more and 680 nm or less. Note that the maximum value of the transmittance within range B3 may be 1.8 times or more, 2 times or more, or 2.5 times or more the transmittance at the minimum wavelength λ3. The maximum value of the transmittance within range B3 is 70% or more, but may be 80% or more or 90% or more.

[0051] The visual transmittance of the filter member is 60% or more. The visual transmittance is also referred to as the visible light transmittance. The visual transmittance is the ratio of the value obtained by multiplying the transmittance of light over the entire visible light band of 380 nm or more and 780 nm or less by the spectral relative visual sensitivity function. By having a high visual transmittance of the filter member, it is possible to sufficiently ensure the amount of light reaching the eyes when viewing the display 110 or an object through the filter member (lens 10). The visual transmittance of the filter member may be 65% or more, 70% or more, or 75% or more.

[0052] Hereinafter, for each of Example 1 and Example 2, the absorption spectrum of the absorption dye contained in the filter member and the specific transmittance spectrum of the filter material will be described in order.

[0053] <Example 1> The filter member according to Example 1 contains five types of absorption dyes C1, C2, C3, C4, and C5 as absorption dye 12. Hereinafter, first, using FIG. 4, the absorption spectra of absorption dyes C1 to C5 will be described.

[0054] FIG. 4 is a diagram showing the absorption characteristics of five types of absorption dyes C1, C2, C3, C4, and C5 contained in the filter member according to Example 1. In FIG. 4, the horizontal axis represents the wavelength (unit: nm), and the vertical axis represents the transmittance (unit: %). Note that the absorption spectrum shown in FIG. 4 is obtained by measuring the transmittance of the transparent substrate in a state where a predetermined amount of absorption dye is dispersed inside the transparent substrate (acrylic substrate). In FIG. 4, the transmittance converted assuming no light absorption by the transparent substrate is shown.

[0055] Absorbing pigment C1 is a copper porphyrin complex and mainly absorbs light near 420 nm. The absorbing pigment C1 used in Example 1 is an example of a first absorbing pigment having an absorption peak (first absorption peak) whose absorption peak wavelength is located within a range A1 of 400 nm or more and 450 nm or less. Specifically, as shown by the thick solid line in FIG. 4, the absorption peak wavelength of the absorbing pigment C1 is about 420 nm, and the transmittance at the absorption peak wavelength is about 26%.

[0056] The half-value width of the absorption peak (first absorption peak) of the absorbing pigment C1 is, for example, 50 nm or less, but may be 40 nm or less, may be 30 nm or less, or may be 20 nm or less. The half-value width of the absorption peak corresponds to the width of the wavelength at the median value between the baseline and the minimum value of the transmittance in the transmittance spectrum. In the example shown in FIG. 4, the baseline of the transmittance for the absorbing pigment C1 is about 100%, and the minimum value of the transmittance is about 26%. Therefore, the half-value width is the width of the absorption peak wavelength when the transmittance is about 63%, and specifically is about 18 nm (= about 429 nm - about 411 nm).

[0057] Also, in the absorption spectrum of the absorbing pigment C1, within at least the visible light band (range of 380 nm or more and 780 nm or less), the transmittance is 95% or more in the range of about 390 nm or less and in the range of about 445 nm or more (however, excluding the range of about 535 nm or more and about 550 nm or less). That is, the absorbing pigment C1 does not substantially absorb light in these wavelength ranges.

[0058] Absorbing pigment C2 is a tetraaza porphyrin metal complex and mainly absorbs light near 585 nm. The absorbing pigment C2 used in Example 1 is an example of a second absorbing pigment having an absorption peak (second absorption peak) whose absorption peak wavelength is located within a range A2 of 540 nm or more and 600 nm or less. Specifically, as shown by the broken line in FIG. 4, the absorption peak wavelength of the absorbing pigment C2 is about 580 nm, and the transmittance at the absorption peak wavelength is about 40%.

[0059] The half-value width of the absorption peak (the second absorption peak) of the absorption dye C2 is, for example, 60 nm or less, but may be 50 nm or less, 40 nm or less, 30 nm or less, or 20 nm or less. In the example shown in FIG. 4, the baseline of the transmittance for the absorption dye C2 is about 100%, and the minimum value of the transmittance is about 40%. Therefore, the half-value width is the width of the absorption peak wavelength when the transmittance is about 70%, and specifically is about 23 nm (= about 593 nm - about 570 nm).

[0060] Also, in the absorption spectrum of the absorption dye C2, within at least the visible light band (the range of 380 nm or more and 780 nm or less), the transmittance is 95% or more in the range of about 510 nm or less and in the range of about 605 nm or more. That is, the absorption dye C2 does not substantially absorb light in these wavelength ranges.

[0061] The absorption dye C3 is a copper phthalocyanine complex and mainly absorbs light near 715 nm. The absorption dye C3 used in Example 1 is an example of a third absorption dye having an absorption peak (the third absorption peak) whose absorption peak wavelength is located within the range A3 of 680 nm or more and 800 nm or less. Specifically, as shown by the dotted line in FIG. 4, the absorption peak wavelength of the absorption dye C3 is about 715 nm, and the transmittance at the absorption peak wavelength is about 59%.

[0062] The half-value width of the absorption peak (the third absorption peak) of the absorption dye C3 is, for example, 60 nm or less, but may be 50 nm or less, 40 nm or less, 30 nm or less, or 20 nm or less. In the example shown in FIG. 4, the baseline of the transmittance for the absorption dye C3 is about 100%, and the minimum value of the transmittance is about 59%. Therefore, the half-value width is the width of the absorption peak wavelength when the transmittance is about 80%, and specifically is about 33 nm (= about 733 nm - about 700 nm).

[0063] In addition, in the absorption spectrum of the absorption dye C3, at least within the visible light band (in the range of 380 nm or more and 780 nm or less), in the range of about 610 nm or less and in the range of about 750 nm or more, the transmittance is 95% or more. That is, the absorption dye C3 does not substantially absorb light in these wavelength ranges.

[0064] The absorption dye C4 is a porphyrin vanadium complex and mainly absorbs light near 430 nm. The absorption dye C4 used in Example 1 is an example of a fourth absorption dye having an absorption peak whose absorption peak wavelength is located within the range A1 of 400 nm or more and 450 nm or less. The absorption peak wavelength of the absorption dye C4 is on the longer wavelength side than that of the absorption dye C1. Specifically, as shown by the thin solid line in FIG. 4, the absorption peak wavelength of the absorption dye C4 is about 430 nm, and the transmittance at the absorption peak wavelength is about 56%.

[0065] The half-value width of the absorption peak (the fourth absorption peak) of the absorption dye C4 is, for example, 50 nm or less, but may be 40 nm or less, may be 30 nm or less, or may be 20 nm or less. In the example shown in FIG. 4, the baseline of the transmittance for the absorption dye C4 is about 100%, and the minimum value of the transmittance is about 56%. Therefore, the half-value width is the width of the absorption peak wavelength when the transmittance is about 78%, and specifically is about 19 nm (= about 439 nm - about 420 nm).

[0066] In addition, in the absorption spectrum of the absorption dye C4, at least within the visible light band (in the range of 380 nm or more and 780 nm or less), in the range of about 400 nm or less and in the range of about 450 nm or more, the transmittance is 95% or more. That is, the absorption dye C4 does not substantially absorb light in these wavelength ranges.

[0067] Absorbing dye C5 is a copper complex of tetraazaporphyrin and mainly absorbs light near 595 nm. The absorbing dye C5 used in Example 1 is an example of a fifth absorbing dye having an absorption peak whose absorption peak wavelength is located within the range A2 of 540 nm or more and 600 nm or less. The absorption peak wavelength of the absorbing dye C5 is on the longer wavelength side than that of the absorbing dye C2. Specifically, as shown by the two-dot chain line in FIG. 4, the absorption peak wavelength of the absorbing dye C5 is about 595 nm, and the transmittance at the absorption peak wavelength is about 50%.

[0068] The full width at half maximum of the absorption peak (the fifth absorption peak) of the absorbing dye C5 is, for example, 60 nm or less, but may be 50 nm or less, 40 nm or less, 30 nm or less, or 20 nm or less. In the example shown in FIG. 4, the baseline of the transmittance for the absorbing dye C5 is about 100%, and the minimum value of the transmittance is about 50%. Therefore, the full width at half maximum is the width of the absorption peak wavelength when the transmittance is about 75%, and specifically, it is about 23 nm (= about 604 nm - about 581 nm).

[0069] Also, in the absorption spectrum of the absorbing dye C5, within at least the visible light band (the range of 380 nm or more and 780 nm or less), the transmittance is 95% or more in the range of about 530 nm or less and the range of about 620 nm or more. That is, the absorbing dye C5 does not substantially absorb light in these wavelength ranges.

[0070] The filter member according to Example 1 contains five types of absorption dyes C1, C2, C3, C4, and C5 in a predetermined ratio. By adjusting the content of each absorption dye, the transmission spectrum of the filter member can be adjusted. The filter member according to Example 1 contains five types of absorption dyes C1, C2, C3, C4, and C5 in a ratio of C1:C2:C3:C4:C5 = 5:15:10:2:5 (weight ratio). More specifically, the filter member contains 7.5 ppm of absorption dye C1, 22.5 ppm of absorption dye C2, 15 ppm of absorption dye C3, 3 ppm of absorption dye C4, and 7.5 ppm of absorption dye C5. (Designed with a plate thickness of 2 mm) The absorption spectra of C1 to C5 shown in FIG. 4 represent the transmission spectra when each absorption dye is contained alone (without being mixed with other absorption dyes) at this content.

[0071] As shown in FIG. 3, in the transmission spectrum of the filter member according to Example 1, due to the filter member containing five types of absorption dyes C1, C2, C3, C4, and C5, the first valley V1, the second valley V2, and the third valley V3 are included in ranges A1, A2, and A3, respectively. Also, in the transmission spectrum of the filter member according to Example 1, due to the transmission spectrum of the base material 11, the fourth valley V4 is included.

[0072] The first valley V1 is a valley in the transmittance formed by absorption dyes C1 and C4. Therefore, the minimum wavelength λ1 of the first valley V1 is substantially the same as the absorption peak wavelength of absorption dye C1 or C4. The minimum wavelength λ1 of the first valley V1 is about 420 nm. The minimum value of the transmittance of the first valley V1, that is, the transmittance at the minimum wavelength λ1, is about 14%.

[0073] The baseline of the first valley V1 can be regarded as the maximum value of the transmittance of peak P2, which is about 85%. Therefore, the half-width of the first valley V1 is the width of the wavelength of the first valley V1 when the transmittance becomes about 49% (= (85% + 14%) ÷ 2), and specifically it is about 26 nm (= about 438 nm - about 412 nm).

[0074] The second valley V2 is a valley of transmittance formed by the absorption dyes C2 and C5. Therefore, the minimum wavelength λ2 of the second valley V2 is substantially the same as the absorption peak wavelength of the absorption dye C2 or C5. The minimum wavelength λ2 of the second valley V2 is about 585 nm. The minimum value of the transmittance of the second valley V2, that is, the transmittance at the minimum wavelength λ2, is about 18%.

[0075] The baseline of the second valley V2 can be regarded as about 85%, which is the maximum value of the transmittance of the peak P2. Therefore, the half-value width of the second valley V2 is the width of the wavelength of the second valley V2 when the transmittance becomes about 51% (= (85% + 18%) ÷ 2), and specifically is about 31 nm (= about 602 nm - about 571 nm).

[0076] The third valley V3 is a valley of transmittance formed by the absorption dye C3. Therefore, the minimum wavelength λ3 of the third valley V3 is substantially the same as the absorption peak wavelength of the absorption dye C3. For example, the minimum wavelength λ3 of the third valley V3 is about 725 nm. The minimum value of the transmittance of the third valley V3, that is, the transmittance at the minimum wavelength λ3, is about 49%.

[0077] The baseline of the third valley V3 can be regarded as about 90%, which is the maximum value of the transmittance of the peak P4. Therefore, the half-value width of the third valley V3 is the width of the wavelength of the third valley V3 when the transmittance becomes about 70% (= (90% + 49%) ÷ 2), and specifically is about 31 nm (= about 742 nm - about 711 nm).

[0078] The fourth valley V4 is a valley caused by the transmission spectrum of the substrate 11. The transmittance of the fourth valley V4 becomes about 0% at about 380 nm. The minimum wavelength λ4 of the fourth valley V4 can be regarded as 380 nm. Note that the fourth valley V4 may not be included in the visible light band.

[0079] The peak wavelength λa of peak P1 is approximately 405 nm. The maximum value of the transmittance of peak P1, that is, the transmittance at the peak wavelength λa, is approximately 61%. Peak P1 has a transmittance of 50% or more over the entire range from approximately 398 nm to approximately 412 nm. In this embodiment, the peak wavelength λa of peak P1 may be included within range B1.

[0080] Note that in Example 1, the maximum value of the transmittance within range B1 is the transmittance when the wavelength is 400 nm, specifically, approximately 56%. Since the transmittance at the minimum wavelength λ1 (= 425 nm) is approximately 14%, the maximum value of the transmittance within range B1 is approximately 4 times the transmittance at the minimum wavelength λ1.

[0081] The peak wavelength λb of peak P2 is approximately 485 nm. The maximum value of the transmittance of peak P2, that is, the transmittance at the peak wavelength λb, is approximately 85%. Peak P2 has a transmittance of 70% or more over the entire range from approximately 443 nm to approximately 528 nm. Also, for peak P2, the transmittance is 80% or more over the entire range from approximately 455 nm to approximately 515 nm. Also, for peak P2, the transmittance is 50% or more over the entire range from approximately 438 nm to approximately 570 nm.

[0082] In Example 1, the peak wavelength λb of peak P2 is included within range B2. The maximum value of the transmittance within range B2 is the transmittance at the peak wavelength λb (= 485 nm), specifically, approximately 85%. Since the transmittance at the minimum wavelength λ2 (= 585 nm) is approximately 18%, the maximum value of the transmittance within range B2 is approximately 4.7 times the transmittance at the minimum wavelength λ2.

[0083] The peak wavelength λc of peak P3 is approximately 630 nm. The maximum value of the transmittance of peak P3, that is, the transmittance at the peak wavelength λc, is approximately 84%. Peak P3 has a transmittance of 70% or more over the entire range from approximately 610 nm to approximately 710 nm. Also, in peak P3, the transmittance is 80% or more over the entire range from approximately 618 nm to approximately 700 nm. Further, in peak P3, the transmittance is 60% or more over the entire range from approximately 607 nm to approximately 716 nm.

[0084] In Example 1, the peak wavelength λc of peak P3 is included within range B3. The maximum value of the transmittance within range B3 is the transmittance at the peak wavelength λc (= 630 nm), specifically, approximately 84%. Since the transmittance at the minimum wavelength λ3 (= 725 nm) is approximately 49%, the maximum value of the transmittance within range B3 is approximately 1.7 times the transmittance at the minimum wavelength λ3.

[0085] The peak wavelength λd of peak P4 is approximately 780 nm. The maximum value of the transmittance of peak P4, that is, the transmittance at the peak wavelength λd, is approximately 90%. Peak P4 has a transmittance of 70% or more over the entire range from approximately 742 nm to approximately 800 nm. Also, in peak P4, the transmittance is 80% or more over the entire range from approximately 747 nm to approximately 800 nm.

[0086] <Example 2> The filter member according to Example 2 contains three types of absorbing dyes C6, C7, and C8 as the absorbing dye 12.

[0087] FIG. 5 is a diagram showing the absorption characteristics of the three types of absorbing dyes C6, C7, and C8 contained in the filter member according to Example 2. In FIG. 5, the horizontal axis represents the wavelength (unit: nm), and the vertical axis represents the transmittance (unit: %). The absorption spectrum shown in FIG. 5 is obtained by measuring the transmittance of the transparent substrate in a state where a predetermined amount of the absorbing dye is dispersed inside the transparent substrate (acrylic substrate). In FIG. 5, the transmittance converted assuming no absorption of light by the transparent substrate is shown.

[0088] The absorption dyes C6 to C8 are the same types of absorption dyes as the absorption dyes C1 to C3 according to Example 1. The peak wavelengths of the absorption peaks of each of the absorption dyes C6 to C8 are the same as the peak wavelengths of the absorption dyes C1 to C3. In the absorption dyes C6 to C8, the transmittance values and the half-value widths at the peak wavelengths may be different from those of the absorption dyes C1 to C3.

[0089] Specifically, as shown by the thick solid line in FIG. 5, the absorption peak wavelength of the absorption dye C6 is about 420 nm, and the transmittance at the absorption peak wavelength is about 26%. The half-value width of the absorption peak (the first absorption peak) of the absorption dye C6 is, for example, 50 nm or less, but may be 40 nm or less, 30 nm or less, or 20 nm or less. In the example shown in FIG. 5, the baseline of the transmittance for the absorption dye C6 is about 100%, and the minimum value of the transmittance is about 26%. Therefore, the half-value width is the width of the absorption peak wavelength when the transmittance is about 63%, and specifically is about 18 nm (= about 429 nm - about 411 nm).

[0090] Also, in the absorption spectrum of the absorption dye C6, within at least the visible light band (range of 380 nm or more and 780 nm or less), the transmittance is 95% or more in the range of about 390 nm or less and the range of about 445 nm or more (however, excluding the range of about 535 nm or more and about 550 nm or less). That is, the absorption dye C6 does not substantially absorb light in these wavelength ranges.

[0091] As shown by the dashed line in FIG. 5, the absorption peak wavelength of the absorption dye C7 is about 580 nm, and the transmittance at the absorption peak wavelength is about 40%. The full width at half maximum (FWHM) of the absorption peak (the second absorption peak) of the absorption dye C7 is, for example, 60 nm or less, but may be 50 nm or less, 40 nm or less, 30 nm or less, or 20 nm or less. In the example shown in FIG. 5, the baseline of the transmittance for the absorption dye C7 is about 100%, and the minimum value of the transmittance is about 40%. Therefore, the FWHM is the width of the absorption peak wavelength when the transmittance is about 70%, and specifically is about 23 nm (= about 593 nm - about 570 nm).

[0092] Also, in the absorption spectrum of the absorption dye C7, within at least the visible light band (the range of 380 nm or more and 780 nm or less), the transmittance is 95% or more in the range of about 510 nm or less and in the range of about 605 nm or more. That is, the absorption dye C7 does not substantially absorb light in these wavelength ranges.

[0093] As shown by the dotted line in FIG. 5, the absorption peak wavelength of the absorption dye C8 is about 715 nm, and the transmittance at the absorption peak wavelength is about 34%. The full width at half maximum (FWHM) of the absorption peak (the third absorption peak) of the absorption dye C8 is, for example, 60 nm or less, but may be 50 nm or less, 40 nm or less, 30 nm or less, or 20 nm or less. In the example shown in FIG. 5, the baseline of the transmittance for the absorption dye C8 is about 100%, and the minimum value of the transmittance is about 34%. Therefore, the FWHM is the width of the absorption peak wavelength when the transmittance is about 67%, and specifically is about 36 nm (= about 734 nm - about 698 nm).

[0094] Also, in the absorption spectrum of the absorption dye C8, within at least the visible light band (the range of 380 nm or more and 780 nm or less), the transmittance is 95% or more in the range of about 610 nm or less and in the range of about 750 nm or more. That is, the absorption dye C8 does not substantially absorb light in these wavelength ranges.

[0095] The filter member according to Example 2 contains three types of absorbing dyes C6, C7, and C8 at a predetermined ratio. By adjusting the content of each absorbing dye, the transmission spectrum of the filter member can be adjusted. The filter member according to Example 2 contains three types of absorbing dyes C6, C7, and C8 at a ratio of C6:C7:C8 = 1:3:2 (weight ratio). More specifically, the filter member contains 7.5 ppm of absorbing dye C6, 22.5 ppm of absorbing dye C7, and 15 ppm of absorbing dye C8. (Design with a plate thickness of 2 mm) Note that the absorption spectra of C6 to C8 shown in FIG. 5 represent the transmission spectra when each absorbing dye is contained alone (without mixing with other absorbing dyes) at this content.

[0096] As shown in FIG. 3, in the transmission spectrum of the filter member according to Example 2, due to the filter member containing three types of absorbing dyes C6, C7, and C8, a first valley V1, a second valley V2, and a third valley V3 are included in ranges A1, A2, and A3, respectively. Also, in the transmission spectrum of the filter member according to Example 2, a fourth valley V4 is included due to the transmission spectrum of the base material 11.

[0097] The first valley V1 is a valley of the transmittance formed by the absorbing dye C6. Therefore, the minimum wavelength λ1 of the first valley V1 is substantially the same as the absorption peak wavelength of the absorbing dye C6. The minimum wavelength λ1 of the first valley V1 is about 420 nm. The minimum value of the transmittance of the first valley V1, that is, the transmittance at the minimum wavelength λ1, is about 20%.

[0098] The baseline of the first valley V1 can be regarded as the maximum value of the transmittance of the peak P2, which is about 85%. Therefore, the half-value width of the first valley V1 is the width of the wavelength of the first valley V1 when the transmittance is about 53% (= (85% + 20%) ÷ 2), and specifically, it is about 21 nm (= about 433 nm - about 411 nm).

[0099] The second valley V2 is a valley of transmittance formed by the absorption dye C7. Therefore, the minimum wavelength λ2 of the second valley V2 is substantially the same as the absorption peak wavelength of the absorption dye C7. The minimum wavelength λ2 of the second valley V2 is approximately 585 nm. The minimum value of the transmittance of the second valley V2, that is, the transmittance at the minimum wavelength λ2, is approximately 28%.

[0100] The baseline of the second valley V2 can be regarded as approximately 85%, which is the maximum value of the transmittance of the peak P2. Therefore, the half-value width of the second valley V2 is the width of the wavelength of the second valley V2 when the transmittance becomes approximately 57% (= (85% + 28%) ÷ 2), and specifically is approximately 23 nm (= approximately 594 nm - approximately 571 nm).

[0101] The third valley V3 is a valley of transmittance formed by the absorption dye C8. Therefore, the minimum wavelength λ3 of the third valley V3 is substantially the same as the absorption peak wavelength of the absorption dye C8. For example, the minimum wavelength λ3 of the third valley V3 is approximately 725 nm. The minimum value of the transmittance of the third valley V3, that is, the transmittance at the minimum wavelength λ3, is approximately 31%.

[0102] The baseline of the third valley V3 can be regarded as approximately 90%, which is the maximum value of the transmittance of the peak P4. Therefore, the half-value width of the third valley V3 is the width of the wavelength of the third valley V3 when the transmittance becomes approximately 61% (= (90% + 31%) ÷ 2), and specifically is approximately 34 nm (= approximately 743 nm - approximately 709 nm).

[0103] The fourth valley V4 is a valley caused by the transmission spectrum of the substrate 11. The transmittance of the fourth valley V4 becomes approximately 0% at approximately 380 nm. The minimum wavelength λ4 of the fourth valley V4 can be regarded as 380 nm. Note that the fourth valley V4 may not be included in the visible light band.

[0104] The peak wavelength λa of peak P1 is approximately 405 nm. The maximum value of the transmittance of peak P1, that is, the transmittance at the peak wavelength λa, is approximately 65%. Peak P1 has a transmittance of 50% or more over the entire range from approximately 398 nm to approximately 412 nm. In this embodiment, the peak wavelength λa of peak P1 may be included within range B1.

[0105] Note that in Example 2, the maximum value of the transmittance within range B1 is the transmittance when the wavelength is 400 nm, specifically, approximately 58%. Since the transmittance at the minimum wavelength λ1 (= 425 nm) is approximately 20%, the maximum value of the transmittance within range B1 is approximately 2.9 times the transmittance at the minimum wavelength λ1.

[0106] The peak wavelength λb of peak P2 is approximately 490 nm. The maximum value of the transmittance of peak P2, that is, the transmittance at the peak wavelength λb, is approximately 85%. Peak P2 has a transmittance of 70% or more over the entire range from approximately 438 nm to approximately 532 nm. Also, for peak P2, the transmittance is 80% or more over the entire range from approximately 454 nm to approximately 521 nm. Also, for peak P2, the transmittance is 50% or more over the entire range from approximately 433 nm to approximately 573 nm.

[0107] In Example 2, the peak wavelength λb of peak P2 is included within range B2. The maximum value of the transmittance within range B2 is the transmittance at the peak wavelength λb (= 490 nm), specifically, approximately 85%. Since the transmittance at the minimum wavelength λ2 (= 585 nm) is approximately 28%, the maximum value of the transmittance within range B2 is approximately 3 times the transmittance at the minimum wavelength λ2.

[0108] The peak wavelength λc of peak P3 is approximately 620 nm. The maximum value of the transmittance of peak P3, that is, the transmittance at the peak wavelength λc, is approximately 84%. Peak P3 has a transmittance of 70% or more over the entire range from approximately 598 nm to approximately 702 nm. Also, in peak P3, the transmittance is 80% or more over the entire range from approximately 606 nm to approximately 637 nm. Further, in peak P3, the transmittance is 60% or more over the entire range from approximately 597 nm to approximately 709 nm.

[0109] In Example 2, the peak wavelength λc of peak P3 is included within range B3. The maximum value of the transmittance within range B3 is the transmittance at the peak wavelength λc (=620 nm), and specifically, it is approximately 84%. Since the transmittance at the minimum wavelength λ3 (=725 nm) is approximately 31%, the maximum value of the transmittance within range B3 is approximately 2.7 times the transmittance at the minimum wavelength λ3.

[0110] The peak wavelength λd of peak P4 is approximately 780 nm. The maximum value of the transmittance of peak P4, that is, the transmittance at the peak wavelength λd, is approximately 90%. Peak P4 has a transmittance of 70% or more over the entire range from approximately 747 nm to approximately 800 nm. Also, in peak P4, the transmittance is 80% or more over the entire range from approximately 752 nm to approximately 800 nm.

[0111] [Function and Effect of Filter Member, etc.] Subsequently, the function and effect of the filter member according to Examples 1 and 2, etc. will be described.

[0112] [Appearance of Display] First, the appearance of a general display 110 will be described with reference to FIGS. 6A and 6B. FIG. 6A is a diagram showing the emission spectrum of display 110. In FIG. 6A, the horizontal axis represents wavelength (unit: nm), and the vertical axis represents light intensity (unit: a.u.).

[0113] As shown in FIG. 6A, the display 110 emits light having peaks in three colors (three wavelengths) of red (R: approximately 590 nm), green (G: approximately 520 nm), and blue (B: approximately 440 nm). The display 110 can display white as a mixed color of the three-color light. At this time, due to partial overlap of the wavelength components between the red light and the green light, the color gamut tends to be narrow.

[0114] On the other hand, by viewing the display 110 through the filter member according to the present embodiment, the color separation of the red light, green light, and blue light emitted by the display 110 can be enhanced. Specifically, the color gamut of the display 110 can be expanded, and the appearance of the display 110 can be improved. This is because the filter member has a transmission spectrum as shown in FIG. 3.

[0115] FIG. 6B is an xy chromaticity diagram for explaining the difference in the color gamut of the display 110 depending on the presence or absence of the filter member according to Examples 1 and 2. FIG. 6B shows a chromaticity diagram (CIE1931) in the xy color system defined by the CIE (International Commission on Illumination).

[0116] In FIG. 6B, the triangle with the three plots marked with triangles as vertices represents the color gamut of the emission color of the display 110. The triangle with the three plots marked with squares as vertices represents the color gamut of the display 110 when viewed through the filter member (lens 10) according to Example 1. The triangle with the three plots marked with circles as vertices represents the color gamut of the display 110 when viewed through the filter member (lens 10) according to Example 2. Note that the plots at the vertices of each triangle correspond to the RGB of the display 110, respectively. The size (area) of the triangle corresponds to the width of the color gamut.

[0117] As shown in FIG. 6B, it can be seen that the color gamut of the display 110 is expanded when viewed through the filter member according to Example 1 or 2. The color gamut extends to the green side (near 550 nm) and the red side (near 610 nm). When the color gamut of the display 110 alone is regarded as 100%, in the case of the filter member according to Example 1, the color gamut is about 115%. In the case of the filter member according to Example 2, the color gamut is about 109%.

[0118] In this way, when viewing the display 110 through the filter member (lens 10), the appearance of the display 110 can be improved. Specifically, the color gamut of the display 110 can be expanded.

[0119] <Appearance of objects other than the display> Subsequently, the appearance of objects other than the display 110 will be described. First, the appearance of an object in an environment irradiated with sunlight will be described with reference to FIGS. 7A and 7B.

[0120] FIG. 7A is a diagram showing the spectrum of sunlight. In FIG. 7A, the horizontal axis represents the wavelength (unit: nm), and the vertical axis represents the light intensity (unit: a.u.). As shown in FIG. 7A, sunlight has a generally high intensity in the visible light band (380 nm or more and 780 nm or less). In the example shown in FIG. 7A, the FCI (figure of merit for colorfulness) of sunlight is 104. The color temperature of sunlight is 5575 K. The chroma value of sunlight is 1.34. Note that the color temperature, FCI, and chroma value are calculated by known techniques based on the emission spectrum.

[0121] FIG. 7B is a diagram showing the spectrum of the transmitted light of sunlight that has passed through the filter members according to Examples 1 and 2. In FIG. 7B, the horizontal axis represents the wavelength (unit: nm), and the vertical axis represents the light intensity (unit: a.u.). FIG. 7B represents the spectrum of the transmitted light of sunlight having the spectrum shown in FIG. 7A.

[0122] As shown in FIG. 7B, sunlight passes through the filter member and is absorbed by the absorption dye contained in the filter member. As a result, three large valleys of transmittance due to the absorption dye are formed in the spectrum of the transmitted light that has passed through the filter member. As a result, as shown in Table 1, the visibility index FCI, color temperature, and chroma value of the transmitted light that has passed through the filter according to Example 1 are 120, 6700K, and 1.18, respectively. The visibility index FCI, color temperature, and chroma value of the transmitted light that has passed through the filter according to Example 2 are 114, 6251K, and 1.06, respectively.

[0123]

Table 1

[0124] Thus, since the visibility index FCI of the transmitted light when sunlight is passed through the filter member is higher than the visibility index FCI of the sunlight before passing through the filter member, the vividness of the object color can be increased. Also, the color temperature of the transmitted light is higher than the color temperature of the sunlight. As a result, the whiteness when viewing a white object under a sunlight irradiation environment can be enhanced. Specifically, it can be confirmed that the chroma value of the transmitted light is lower than the chroma value of the sunlight, and the whiteness of the white object is increased.

[0125] Next, how an object appears under an illumination environment by a general lighting device (lighting device 120 shown in FIG. 2) will be described with reference to FIGS. 8A and 8B.

[0126] FIG. 8A is a diagram showing the spectrum of white light from a white LED. In FIG. 8A, the horizontal axis represents the wavelength (unit: nm), and the vertical axis represents the light intensity (unit: a.u.). As shown in FIG. 8A, white light (hereinafter simply referred to as white light) from a general white LED has a peak in light emission intensity at blue (near 460 nm), and has a gentle and wide half-value width peak from green to red. In the example shown in FIG. 8A, the visibility index FCI of the white light is 97. The color temperature of the white light is 5154K. The chroma value of the white light is 1.37.

[0127] Figure 8B is a diagram showing the spectrum of transmitted white light that has passed through the filter member according to Examples 1 and 2. In Figure 8B, the horizontal axis represents wavelength (unit: nm), and the vertical axis represents light intensity (unit: a.u.). Figure 8B represents the spectrum of transmitted light of sunlight having the spectrum shown in Figure 8A.

[0128] As shown in Figure 8B, white light is absorbed by the absorption dyes contained in the filter member as it passes through the filter member. As a result, three large valleys of transmittance due to the absorption dyes are formed in the spectrum of the transmitted light that has passed through the filter member. As a result, as shown in Table 2, the visibility index FCI, color temperature, and chroma value of the transmitted light that has passed through the filter according to Example 1 are 116, 6900K, and 1.04, respectively. The visibility index FCI, color temperature, and chroma value of the transmitted light that has passed through the filter according to Example 2 are 111, 6070K, and 0.52, respectively.

[0129]

Table 2

[0130] Thus, when white light from a white LED is passed through the filter member, the visibility index FCI of the transmitted light is higher than the visibility index FCI of the white light before passing through the filter member, so the vividness of the object color can be increased. Also, the color temperature of the transmitted light is higher than the color temperature of the white light. Thereby, the whiteness when viewing a white object under an irradiation environment of white light from a white LED can be enhanced. Specifically, it can be confirmed that the chroma value of the transmitted light is lower than the chroma value of the white light, and the whiteness of the white object is increased.

[0131] Table 3 also shows the FCI (flare index), color temperature, and chroma value of the transmitted light when equal-energy white light is passed through the filter members according to Examples 1 and 2. Equal-energy white light is white light in which the energy of each wavelength in the visible light band is equal. The flare index FCI of equal-energy white light is 108. The color temperature of equal-energy white light is 5456K. The chroma value of equal-energy white light is 1.13.

[0132] [Table 3]

[0133] As shown in Table 3, the flare index FCI, color temperature, and chroma value of the transmitted light that has passed through the filter according to Example 1 are 125, 6700K, and 1.18, respectively. The flare index FCI, color temperature, and chroma value of the transmitted light that has passed through the filter according to Example 2 are 119, 6007K, and 0.62, respectively.

[0134] Thus, when equal-energy white light is passed through the filter member, the flare index FCI of the transmitted light is higher than the flare index FCI of the equal-energy white light before passing through the filter member, so the vividness of the object color can be increased. Specifically, the flare index FCI of the transmitted light is 110 or more. Also, the color temperature of the transmitted light is higher than the color temperature of the white light. Specifically, the color temperature of the transmitted light is 6200K or more. Thereby, the whiteness when seeing a white object in an irradiation environment of equal-energy white light can be enhanced. Specifically, it can be confirmed that the chroma value of the transmitted light is lower than the chroma value of the equal-energy white light, and the whiteness of the white object is enhanced.

[0135] [Modification Example] Subsequently, a modification example of the lens 10 according to the above-described embodiment will be described. In the above-described embodiment, the entire lens 10 is a filter member. In contrast, in the lens according to this modification example, the filter member is provided only in a part. Hereinafter, the description will be centered on the differences from the embodiment, and the description of the common points will be omitted or simplified.

[0136] FIG. 9 is an external perspective view of a lens 20 including a filter member according to this modified example and glasses 2 including the lens 20. As shown in FIG. 9, the lens 20 includes a first region 21 where a filter member is provided and a second region 22 where no filter member is provided.

[0137] When the lens 20 is viewed from the front, the area of the filter member, that is, the area of the first region 21, is at least half of the area of the lens 20. The area of the first region 21 is equal to or larger than the area of the second region 22. In the example shown in FIG. 9, the first region 21 is provided above the second region 22, but it is not limited thereto. The first region 21 is located at the center of the lens 20 and may be surrounded by the second region 22.

[0138] [Summary] The filter member according to the first aspect of the present invention is a filter member included in a member worn by a user U, and includes a base material 11 and one or more absorption dyes 12 dispersed in the base material 11. The transmittance spectrum of the filter member has a first valley V1 in which a first minimum wavelength λ1 is located in the range of 400 nm or more and 450 nm or less, a second valley V2 in which a second minimum wavelength λ2 is located in the range of 540 nm or more and 600 nm or less, and a third valley V3 in which a third minimum wavelength λ3 is located in the range of 680 nm or more and 800 nm or less. The maximum value of the transmittance of the filter member in the range of 350 nm or more and 400 nm or less is 2.5 times or more the transmittance of the filter member at the first minimum wavelength λ1. The maximum value of the transmittance of the filter member in the range of 450 nm or more and 540 nm or less is 3 times or more the transmittance of the filter member at the second minimum wavelength λ2. The maximum value of the transmittance of the filter member in the range of 600 nm or more and 680 nm or less is 1.6 times or more the transmittance of the filter member at the third minimum wavelength λ3.

[0139] This can improve the visibility of both the display 110 and the object (e.g., the foliage plant 130). Specifically, the color gamut of the display 110 can be expanded, and the whiteness of the object can be enhanced.

[0140] The filter member according to the second aspect of the present invention is the filter member according to the first aspect, wherein the maximum value of the transmittance of the filter member within the range of 350 nm or more and 400 nm or less is 50% or more, the maximum value of the transmittance of the filter member within the range of 450 nm or more and 540 nm or less is 70% or more, and the maximum value of the transmittance of the filter member within the range of 600 nm or more and 680 nm or less is 70% or more.

[0141] This can allow the light corresponding to RGB to pass through with a high transmittance, so that it is possible to suppress the difficulty in viewing the display 110 and the object due to insufficient light quantity.

[0142] The filter member according to the third aspect of the present invention is the filter member according to the first aspect or the second aspect, wherein the visual transmittance of the filter member is 60% or more.

[0143] This has a high transmittance in the visible light band, so that the visibility of both the display 110 and the object can be improved.

[0144] The filter member according to the fourth aspect of the present invention is the filter member according to any one of the first aspect to the third aspect, wherein the transmittance of the filter member at the first minimum wavelength λ1 is 10% or more and 20% or less, the transmittance of the filter member at the second minimum wavelength λ2 is 10% or more and 30% or less, and the transmittance of the filter member at the third minimum wavelength λ3 is 30% or more and 60% or less.

[0145] This can sufficiently suppress the wavelength components to be suppressed from passing through. For example, the transmission of the overlapping portion of the red light and the green light from the display 110 can be suppressed, and the color gamut of the display 110 can be expanded.

[0146] The filter member according to the fifth aspect of the present invention is a filter member according to any one of the first to fourth aspects, and the visibility index FCI of the transmitted light when equal-energy white light is passed through the filter member is 110 or more.

[0147] As a result, by increasing the visibility index FCI of the transmitted light, the color reproducibility can be improved, and the vividness of the color of an object can be increased.

[0148] The filter member according to the sixth aspect of the present invention is a filter member according to any one of the first to fifth aspects, and the color temperature of the transmitted light when equal-energy white light is passed through the filter member is 6200K or more.

[0149] As a result, by increasing the color temperature of the transmitted light, the whiteness when seeing a white object can be enhanced.

[0150] The filter member according to the seventh aspect of the present invention is a filter member according to any one of the first to sixth aspects, and the base material 11 is a resin base material.

[0151] As a result, the absorption dye 12 can be easily mixed into the base material 11. In addition, since a material having excellent transparency can be used as the resin base material, the transmittance of the filter member according to this aspect can be increased. Further, since molding is easy, the shape of the filter member according to this aspect can be easily made into a desired shape.

[0152] The lens according to the eighth aspect of the present invention is, for example, the above-described lens 10 or 20, and is a lens for glasses including a filter member according to any one of the first to seventh aspects. The lens according to this aspect may be a lens for sunglasses or a lens for goggles.

[0153] As a result, glasses, sunglasses, or goggles equipped with lens 10 or 20 can be worn on the head of user U, enabling the user's hands to be free. Since the hands are free, work efficiency can be enhanced in work system 100.

[0154] The lens according to the ninth aspect of the present invention is the lens according to the eighth aspect, and when the lens is viewed from the front, the area of the filter member is at least half of the area of the lens.

[0155] As a result, the filter member can be provided only in the necessary area of the lens. It becomes possible to distinguish between the case of viewing an object through the filter member and the case of viewing an object without using the filter member.

[0156] (Other) As described above, the filter member and the lens according to the present invention have been described based on the above-described embodiments and the like. However, the present invention is not limited to the above-described embodiments.

[0157] For example, the transmittance spectrum of the filter member shown in FIG. 3 is merely an example. As long as the object of the present disclosure can be achieved, the transmittance spectrum may be adjusted as follows. For example, the maximum value of the transmittance of the filter member within range B1 may be less than 50%. The maximum value of the transmittance of the filter member within range B2 may be less than 70%. The maximum value of the transmittance of the filter member within range B3 may be less than 70%. The visual transmittance of the filter member may be less than 60%. The transmittance of the filter member at the first minimum wavelength λ1 may be less than 10% or may be 20% or more. The transmittance of the filter member at the second minimum wavelength λ2 may be less than 10% or may be 30% or more. The transmittance of the filter member at the third minimum wavelength λ3 may be less than 30% or may be less than 60%.

[0158] Also, for example, in the above-described embodiments, the transmission spectrum of the filter member is constituted by five or three types of absorption dyes, but it is not limited thereto. For example, the absorption dye contained in the filter member may be only one type, may be only two types, or may be only four types. Alternatively, the filter member may contain six or more types of absorption dyes.

[0159] Also, for example, an example where the base material 11 is a resin base material is shown, but it is not limited thereto. The base material 11 may be a glass base material or a quartz base material, etc.

[0160] Also, for example, the filter member may be used for contact lenses. The present invention may be glasses, sunglasses or goggles provided with the filter member, or may be a contact lens provided with the filter member.

[0161] In addition, forms obtained by applying various modifications conceivable by those skilled in the art to each embodiment, and forms realized by arbitrarily combining the components and functions in each embodiment without departing from the gist of the present invention are also included in the present invention.

Explanation of Reference Numerals

[0162] 1, 2 Glasses 10, 20 Lenses 11 Base material 12 Absorption dye 110 Display

Claims

1. A filter member provided in a member worn by a user, comprising: a base material; one or more absorption dyes dispersed in the base material, and having: The transmission spectrum of the filter member has: a first valley in which a first minimum wavelength is located within a range of 400 nm or more and 450 nm or less; a second valley in which a second minimum wavelength is located within a range of 540 nm or more and 600 nm or less; a third valley in which a third minimum wavelength is located within a range of 680 nm or more and 800 nm or less; The maximum value of the transmittance of the filter member within a range of 350 nm or more and 400 nm or less is 2.5 times or more the transmittance of the filter member at the first minimum wavelength; The maximum value of the transmittance of the filter member within a range of 450 nm or more and 540 nm or less is 3 times or more the transmittance of the filter member at the second minimum wavelength; The maximum value of the transmittance of the filter member within a range of 600 nm or more and 680 nm or less is 1.6 times or more the transmittance of the filter member at the third minimum wavelength. Filter member.

2. The maximum value of the transmittance of the filter member within a range of 350 nm or more and 400 nm or less is 50% or more; The maximum value of the transmittance of the filter member within a range of 450 nm or more and 540 nm or less is 70% or more; The maximum value of the transmittance of the filter member within a range of 600 nm or more and 680 nm or less is 70% or more. The filter member according to claim 1.

3. The visual transmittance of the filter member is 60% or more. The filter member according to claim 1.

4. The transmittance of the filter member at the first minimum wavelength is 10% or more and 20% or less; The transmittance of the filter member at the second minimum wavelength is 10% or more and 30% or less; The transmittance of the filter member at the third minimum wavelength is 30% or more and 60% or less. The filter member according to any one of claims 1 to 3.

5. When equal-energy white light is passed through the filter member, the visibility index FCI (Feeling of Contrast Index) of the transmitted light is 110 or more. The filter member according to any one of claims 1 to 3.

6. When equal-energy white light is passed through the filter member, the color temperature of the transmitted light is 6200 K or more. The filter member according to any one of claims 1 to 3.

7. The base material is a resin base material. The filter member according to any one of claims 1 to 3.

8. A lens for glasses, sunglasses or goggles, comprising the filter member according to any one of claims 1 to 3.

9. The lens according to claim 8, wherein when the lens is viewed from the front, the area of the filter member is at least half of the area of the lens. ​

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