JP2024070791A - Vehicle lighting fixtures - Google Patents

Abstract

[Problem] To provide a vehicle lamp. [Solution] A vehicle lamp comprising a light guide plate having a plurality of light emitting sections and low brightness sections located between adjacent light emitting sections and emitting light with a lower brightness than the brightness of the light emitted from the light emitting sections, a plurality of light sources that input light having an emission peak wavelength in the range of 420 nm to 550 nm to the light guide plate, and a wavelength conversion member that is disposed on the light emitting sections and converts the wavelength of the light emitted from the light emitting sections to emit light having an emission peak wavelength in the range of 540 nm to 700 nm. [Selected Figure] Figure 1A

Description

This disclosure relates to vehicle lighting.

Automobiles are required to have brake lights (stop lamps, brake lamps), direction indicators (turn signal lamps, blinkers), tail lights, reverse lights, and rear reflectors on the rear of the vehicle body, and standards are also set for the color and brightness of the light and reflected light. These various lamps are combined into one unit and attached to the vehicle body as a pair of rear combination lamps on the left and right. A typical rear combination lamp uses a vehicle lamp that emits light of two or three colors, at least one of red for both brake lights (stop) and tail lights, amber for direction indicators (turn signals), and white for reverse lights (back lights), into separate compartments in the area that is the light extraction section. Vehicle lamps such as rear combination lamps are sometimes designed as automobile decorations with unique color schemes and shapes based on the light color.

In such vehicle lamps, a light-emitting device having a light-emitting diode (LED) or the like is used as a light source, and is housed in a lamp body with a reflective film or the like on the inner surface. The opening of the lamp body, which is the light extraction part, is covered with a cover (outer lens) made of transparent resin or the like to form the light emission surface. In vehicle lamps such as rear combination lamps, a structure is sometimes used in which a light-guiding member having a light-emitting surface that is the light extraction part extending in a direction perpendicular to the end face is used, and the light of the light-emitting device is made to enter the end face of the light-guiding member and the light is extracted from the light-emitting surface of the light-guiding member. For example, Patent Document 1 discloses a vehicle lamp that includes a light-guiding lens as a light-guiding member and emits light of different colors from multiple light sources of the same color tone to each of the multiple partitions on the light-guiding lens's light-emitting surface. Patent Document 1 discloses a vehicle lamp having a bottom and side surfaces, the side surfaces being formed of light-shielding partition walls, a plurality of optically separated recesses filled with a fluorescent resin in which different phosphors are mixed into the light-transmitting resin, and LEDs of the same type are arranged near the light-transmitting walls of each recess with their illumination direction facing the recess. The vehicle lamp disclosed in Patent Document 1 changes the type of phosphor contained in the fluorescent resin filled in each recess, so that light of a different color tone from the light emitted from the light source is emitted from the bottom of each of the recesses.

JP 2009-206064 A

One aspect of the present disclosure aims to provide a vehicle lamp that is capable of emitting light from each of a number of partitions in an area that serves as a light extraction section, thereby reducing unevenness in the brightness of the light emitted within each partition.

The first aspect is a vehicle lamp including a light guide plate having a plurality of light emitting sections and low brightness sections located between adjacent light emitting sections and emitting light with a lower brightness than the brightness of the light emitted from the light emitting sections, a plurality of light sources that input light having an emission peak wavelength in the range of 420 nm to 550 nm into the light guide plate, and a wavelength conversion member that is disposed on the light emitting sections and converts the wavelength of the light emitted from the light emitting sections to emit light having an emission peak wavelength in the range of 540 nm to 700 nm.

The second aspect is a vehicle lamp that includes a plurality of light guide plates having light emitting portions, a plurality of light sources that input light having an emission peak wavelength in the range of 420 nm to 550 nm to the light guide plates, and a wavelength conversion member that is disposed on the light emitting portions and converts the wavelength of the light emitted from the light emitting portions to emit light having an emission peak wavelength in the range of 540 nm to 700 nm.

According to one aspect of the present disclosure, a vehicle lamp can be provided that is capable of emitting light from each of a number of divided sections in an area that serves as a light extraction section, thereby reducing unevenness in the brightness of the light emitted within each section.

1 is a schematic plan view showing an example of a vehicle lamp; 1B is a schematic side view of the vehicular lamp shown in FIG. 1A as viewed in the direction of an arrow 1B. FIG. 2 is a schematic plan view of the vehicle lamp showing a state of light entering a light output portion from each light source; 3B is a schematic cross-sectional view of the vehicle lamp shown in FIG. 2A, showing a state of light in the direction of an arrow 3B. FIG. 1 is a schematic plan view showing an example of a light guide plate provided in a vehicle lamp. 3B is a schematic side view of the light guide plate of FIG. 3A as viewed in the direction of arrow 3B. FIG. 2 is a partially enlarged side view showing an example of a light guide plate provided in a vehicle lamp. 1 shows a schematic side view of an example of a vehicle lamp. 1 shows a schematic side view of an example of a vehicle lamp. 1 is a schematic plan view showing an example of a vehicle lamp; 6B is a schematic cross-sectional view of the vehicle lamp shown in FIG. 6A as viewed in the direction of an arrow 6B. 1 is a schematic plan view showing an example of a light guide plate provided in a vehicle lamp. 7B is a schematic cross-sectional view of the light guide plate of FIG. 7A as viewed in the direction of arrow 7B. 1 is a schematic cross-sectional view of an example of a vehicle lamp. 1 is a schematic side view of an example of a vehicle lamp. 1 is a schematic side view of an example of a vehicle lamp. FIG. 1 is a diagram showing regions R, A, and W in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram. FIG. 2 is an external view showing a schematic diagram of a state in which the vehicle lamp is attached to a vehicle body. FIG. 1 is a cross-sectional view that illustrates a vehicle lamp. 1 is a photograph of the appearance of one light emitting portion from which light is emitted, taken from the light extraction side of the wavelength conversion member. The luminance of a part of a light emitting portion and a part of a low luminance portion measured for each pixel from the light extraction side of the wavelength conversion member is shown. The luminance of a portion of one light emitting portion measured for each pixel from the light extraction side of the wavelength conversion member is shown.

The following describes an embodiment of the present disclosure based on the drawings. However, the following embodiment is an example of a vehicle lamp for embodying the technical idea of the present disclosure, and the present disclosure is not limited to the vehicle lamp shown below. In addition, the members shown in the claims are in no way limited to the members of the embodiments. In particular, the dimensions, materials, shapes, and relative positions of the components described in the embodiments are merely illustrative examples, and are not intended to limit the scope of the present disclosure, unless otherwise specified. The relationship between color names and chromaticity coordinates, the relationship between the wavelength range of light and the color names of monochromatic light, etc., are in accordance with JIS Z8110. The members shown in the drawings may be exaggerated in size and positional relationship, and the shapes may be simplified. In the following description, the same names and symbols generally indicate members of the same or similar quality. In this specification, terms such as "plate," "sheet," "film," and "layer" are not distinguished from each other based only on the difference in name. Thus, for example, "plate" is used to include members that may be called sheets, films, or layers, and "layer" is used to include members that may be called plates, sheets, or films. In this specification, the terms "upper" and "lower" are also used to refer to the side from which light is extracted and the opposite side in a light-emitting device. For example, "upper" means the direction in which light is extracted, and "lower" means the opposite direction. Furthermore, "upper surface" means the surface on the side from which light is extracted, and "lower surface" means the opposite surface. Furthermore, side surface means the surface perpendicular to the upper or lower surface.

The vehicle lamp of the first embodiment includes a light guide plate having a plurality of light emitting sections and low brightness sections located between adjacent light emitting sections and emitting light with a lower brightness than the brightness of the light emitted from the light emitting sections, a plurality of light sources that input light having an emission peak wavelength in the range of 420 nm to 550 nm into the light guide plate, and a wavelength conversion member that is disposed on the light emitting sections and converts the wavelength of the light emitted from the light emitting sections to emit light having an emission peak wavelength in the range of 540 nm to 700 nm.

Below, an example of a vehicle lamp is described with reference to the drawings. The size and positional relationship of each component in the drawings are merely examples and may be exaggerated.

Figure 1A is a schematic plan view showing an example of a vehicle lamp 10 of the first embodiment. Figure 1B is a schematic side view of the vehicle lamp 10 shown in Figure 1A as viewed from the direction of the arrow 1B. The vehicle lamp 10 includes a light guide plate 1 having a plurality of light emitting sections 1a and a low brightness section 1b located between adjacent light emitting sections 1a, 1a, which emits light having a brightness lower than the brightness of the light emitted from the light emitting section 1a, a plurality of light sources 2 that input light having an emission peak wavelength in the range of 420 nm to 550 nm into the light guide plate 1, and a wavelength conversion member 3 that is arranged on the light emitting section 1a and converts the wavelength of the light emitted from the light emitting section 1a to emit light having an emission peak wavelength in the range of 540 nm to 700 nm. The wavelength conversion member 3 includes at least one type of phosphor 31, which will be described later. The direction in which light is emitted from the light emitting section 1a and the wavelength conversion member 3 means the +z direction in the figure. When a vehicle lamp 10 including a light guide plate 1 is placed on a vehicle body, a region that serves as a light extraction portion is formed in the direction in which light from the wavelength conversion member 3 is emitted. In FIG. 1B, the wavelength conversion member 3 is placed on the light guide plate 1 at a distance from the light guide plate 1. The wavelength conversion member 3 may also be placed in direct contact with the upper surface of the light guide plate 1.

2A is an image diagram showing the state of light incident from each light source 2 to each light emitting portion 1a in a schematic plan view of the vehicle lamp 10. In FIG. 2A, the arrows represent the state of light. FIG. 2B is an image diagram showing the state of light in a schematic cross section of the vehicle lamp shown in FIG. 2A as viewed from the direction of the arrow 2B. In FIG. 2B, the light emitting portion 1a and the low brightness portion 1b of the light guide plate 1 are typically represented. In FIG. 2B, the arrows represent the state of light. The vehicle lamp 10 has a plurality of light emitting portions 1a in the light guide plate 1, and a plurality of light sources 2 are arranged at positions where light is incident on the light emitting portion 1a. The wavelength conversion member 3 is arranged so as to cover the plurality of light emitting portions 1a. The light incident on the light guide plate 1 from the light source 2 is guided within the light guide plate 1, the optical path is deflected, and the light is diffused and emitted from the light emitting portion 1a. The wavelength of the light emitted from the light emitting portion 1a is converted by the phosphor 31 contained in the wavelength conversion member 3, and the light is further diffused by the wavelength conversion member 3, so that light with reduced brightness unevenness can be emitted over the entire surface of the light emitting portion 1a.

An example of a light guide plate used in a vehicle lamp will be described with reference to the drawings. FIG. 3A is a schematic plan view showing an example of a light guide plate 1 provided in a vehicle lamp of the first embodiment. FIG. 3B is a schematic side view of the light guide plate 1 in FIG. 3A as viewed from the direction of the arrow 3B. The light guide plate 1 has a plurality of light emitting sections 1a and a low brightness section 1b located between adjacent light emitting sections 1a, 1a and emitting light having a brightness lower than the brightness of the light emitted from the light emitting sections 1a, 1a. The light guide plate 1 is divided into a plurality of sections by the light emitting sections 1a and the low brightness sections 1b. When the light guide plate 1 is used as a surface light source, the vehicle lamp 10 including the light guide plate 1 emits light from one of the sections divided into a plurality of sections by the light emitting sections 1a and the low brightness sections 1b of the light guide plate 1 in the region that becomes the light extraction section where the surface light source is arranged. In order for the light guide plate 1 having multiple light emitting portions 1a to become a surface light source, light may be emitted from one light emitting portion 1a which is one section in an area where the vehicle lamp 10 is arranged and serves as a light extraction portion, and light of a different color tone may be emitted from each section. The light guide plate 1 guides the incident light, deflects the optical path of the guided light, and causes the light to exit from the light emitting portion 1a. The light guide plate 1 can be made of a transparent material with a relatively high refractive index. Examples of materials for forming the light guide plate 1 include polycarbonate (PC) resin, polymethyl methacrylate resin (PMMA), polyacrylate resin, acrylic resin, glass, etc.

Figure 3C is a partially enlarged side view showing an example of a light guide plate 1. As an example, the light guide plate 1 has irregularities 1c formed on the light output section 1a side and/or the opposite side of the light output section 1a. The irregularities 1c deflect the optical path of light that is incident on and guided into the light guide plate 1, causing the light to exit from the light output section 1a. Between adjacent light output sections 1a, 1a, low-luminance sections 1b are arranged in which no irregularities 1c are formed or in which the number of irregularities 1c is small. The low-luminance sections 1b have difficulty emitting light to the outside of the light guide plate 1, for example, because no irregularities 1c are formed, and the optical path of the light is deflected within the low-luminance sections 1b of the light guide plate 1. Instead of providing the irregularities 1c, for example, a resin layer containing a light diffusing agent with a higher refractive index than the base material of the light guide plate 1 may be disposed on the lower surface side of the light guide plate 1 located below the light emitting portion 1a, and a resin layer containing a light diffusing agent with a lower refractive index than the base material of the light guide plate 1 may be disposed on the lower surface side of the light guide plate 1 located below the low brightness portion 1b. The irregularities 1c that become the light emitting portion 1a may be formed by a mold when the light guide plate 1 is molded, or may be formed by a printing process such as screen printing or silk printing. The irregularities 1c may also be formed by sandblasting or the like.

The light source preferably emits light having an emission peak wavelength in the range of 420 nm to 550 nm. The light source may be a light emitting element, or may be a light emitting device including a light emitting element and a package in which the light emitting element is arranged. The plurality of light sources may emit light having different emission peak wavelengths. The light source may be a light source that emits light having an emission peak wavelength in the range of 420 nm to 470 nm. The light source may be a light source that emits light having an emission peak wavelength in the range of 500 nm to 550 nm. The light source may be a light source that has an emission peak wavelength in the range of 470 nm to 550 nm. The light emitting element may be, for example, a light emitting diode (LED) or a laser diode (LD). The light emitting element may be a semiconductor light emitting element using a nitride semiconductor represented by In _x Al _y Ga _1-X-Y N (0≦X, 0≦Y, X+Y≦1). The nitride semiconductor may have a variety of emission wavelengths depending on the material of the semiconductor layer and its mixed crystal degree. The light emitting element is not particularly limited in shape, size, mounting form (flip chip, wire bonding), etc., so long as it emits the amount of light required for a vehicle lamp.

The wavelength conversion member may be a plate-, sheet-, or layer-shaped member containing a translucent material and a phosphor. The translucent material may be at least one selected from the group consisting of resin, glass, and inorganic material. The resin used for the translucent material is preferably at least one selected from the group consisting of epoxy resin, silicone resin, phenolic resin, and polyimide resin. The inorganic material used for the translucent material may be at least one selected from the group consisting of aluminum oxide and aluminum nitride. In addition to the translucent material and the phosphor, the wavelength conversion member may contain a light diffusing agent, a coloring agent, and the like as necessary. Examples of the light diffusing agent include silicon oxide, barium titanate, titanium oxide, and aluminum oxide. When the wavelength conversion member contains a light diffusing agent, it is preferable to use a light diffusing agent made of a material having a refractive index different from that of the translucent material. When the translucent material of the wavelength conversion member is, for example, a silicone resin, the light diffusing agent may be at least one inorganic material selected from the group consisting of aluminum oxide and aluminum nitride, which has a refractive index different from that of the silicone resin.

The thickness of the wavelength conversion member is preferably in the range of 18 μm to 100 μm, more preferably in the range of 20 μm to 100 μm, even more preferably in the range of 22 μm to 90 μm, even more preferably in the range of 23 μm to 90 μm, and may be in the range of 30 μm to 90 μm, or may be in the range of 40 μm to 80 μm. If the thickness of the wavelength conversion member is in the range of 18 μm to 100 μm, the desired content of phosphor can be contained in the wavelength conversion member so as to achieve the desired wavelength range while maintaining the heat dissipation properties of the wavelength conversion member. In addition, if the thickness of the wavelength conversion member is in the range of 18 μm to 100 μm, it is easy to store the vehicle lamp in the lamp body mounted on the vehicle body.

The wavelength conversion member contains at least one type of phosphor, and may contain two or more types of phosphors with different compositions or emission peak wavelengths.

The wavelength conversion member is preferably at least one phosphor selected from the group consisting of a rare earth aluminate phosphor having a composition represented by the following formula (1) (hereinafter also referred to as a "YAG phosphor"), a first nitride phosphor having a composition represented by the following formula (2) (hereinafter also referred to as an "α-sialon phosphor"), a second nitride phosphor having a composition represented by the following formula (3) (hereinafter also referred to as a "BSESN phosphor"), a third nitride phosphor having a composition represented by the following formula (4) (hereinafter also referred to as a "SCASN phosphor"), a fourth nitride phosphor having a composition represented by the following formula (5) (hereinafter also referred to as a "CASN phosphor"), a fifth nitride phosphor having a composition represented by the following formula (6) (hereinafter also referred to as an "SLA phosphor"), a first fluoride phosphor having a composition represented by the following formula (7) (hereinafter also referred to as a "KSF phosphor"), and a second fluoride phosphor having a composition represented by the following formula (8) (hereinafter also referred to as a "KSAF phosphor").
^R13 ( _{AlcGab ) 5O12 : Cea} ( ₁ )
In formula (1), ^R1 is at least one selected from the group consisting of Y, Gd, Lu and Tb, and a, b and c satisfy 0<a≦0.22, 0≦b≦0.4, 0<c≦1.1 and 0.9≦b+c≦1.1.
M ¹ _d Si _{12-(e + f)} Al _{e + f} O _f N _16-f : Eu (2)
In formula (2), ^M1 contains at least one element selected from the group consisting of Li, Mg, Ca, Sr, Y, and lanthanoid elements (excluding La and Ce), and d, e, and f respectively satisfy 0<d≦2.0, 2.0≦e≦6.0, and 0≦f≦1.0.
^M22Si5N8 _: Eu _{( 3} )
In formula (3), ^M2 is an alkaline earth metal element including at least one selected from the group consisting of Ca, Sr, and Ba.
Sr _g C a _h A l _i S _{i j} N _k : Eu (4)
In formula (4), g, h, i, j, and k respectively satisfy 0≦g<1, 0<h≦1, g+h≦1, 0.9≦i≦1.1, 0.9≦j≦1.1, and 2.5≦k≦3.5.
_CaAlSiN3 :Eu (5)
^M3mM4nAl3 _- ^pSipNq _: ^M5 _{( 6 )}
In formula (6), ^M3 is at least one element selected from the group consisting of Ca, Sr, Ba, and Mg, ^M4 is at least one element selected from the group consisting of Li, Na, and K, ^M5 is at least one element selected from the group consisting of Eu, Ce, Tb, and Mn, and m, n, p, and q each satisfy 0.80≦m≦1.05, 0.80≦n≦1.05, 0≦p≦0.5, and 3.0≦q≦5.0, respectively.
A ¹ _s [M ⁶ _r Mn ^{4 +} _r F _t ] (7)
In the formula (7), A ¹ is at least one ion selected from the group consisting of K ⁺ , Li ⁺ , Na ⁺ , Rb ⁺ , Cs ⁺ and NH ₄ ⁺ , M ⁶ is at least one element selected from the group consisting of Group 4 elements and Group 14 elements, r satisfies 0<r<0.2, s is the absolute value of the charge of the [M ⁶ _1-r Mn ⁴⁺ _r F _t ] ion, and t satisfies 5<t<7. In the formula (7), A ¹ preferably contains at least K ⁺ , and M ⁶ preferably contains at least Si.
A ² _w [M ⁷ _1-u-v M ⁸ _v Mn ^{4 +} _u F _x ] (8)
In the formula (8), A ² is at least one ion selected from the group consisting of K ⁺ , Li ⁺ , Na ⁺ , Rb ⁺ , Cs ⁺ and NH ₄ ⁺ , M ⁷ is at least one element selected from the group consisting of Group 4 and Group 14, M ⁸ is at least one element selected from the group consisting of Group 13, u satisfies 0<u<0.2, w is the absolute value of the charge of the [M ⁷ _1-u-v M ⁸ _v Mn ⁴⁺ _u F _x ] ion, v satisfies 0<v≦0.1, and x satisfies 5<x<7.) In the formula (8), A ² preferably contains at least K ⁺ , M ⁷ preferably contains at least Si, and M ⁸ preferably contains at least Al.

The volume average particle diameter of the phosphor is preferably in the range of 5 μm to 35 μm, more preferably in the range of 6 μm to 35 μm, even more preferably in the range of 6 μm to 30 μm, even more preferably in the range of 6 μm to 20 μm, and particularly preferably in the range of 6 μm to 15 μm. If the volume average particle diameter of the phosphor is in the range of 5 μm to 35 μm, the thickness of the wavelength conversion member containing the phosphor can be thinned, and the vehicle lamp can be easily stored in the lamp body mounted on the vehicle body. Also, if the volume average particle diameter of the phosphor is in the range of 6 μm to 35 μm, the thickness of the wavelength conversion member can be thinned, and the weight can be reduced. The volume average particle diameter of the phosphor refers to the particle diameter that reaches 50% cumulatively from the small diameter side in the volume-based particle size distribution. The volume-based particle size distribution of the phosphor can be measured by a laser diffraction type particle size distribution measuring device (e.g., Master Sizer 3000, manufactured by Malvern Panalytical).

When the volume average particle diameter of the phosphor is in the range of 5 μm to 35 μm, the wavelength conversion member containing the phosphor can be thinned to a thickness of 18 μm to 100 μm, which is preferable. When the volume average particle diameter of the phosphor is in the range of 6 μm to 35 μm, the wavelength conversion member containing the phosphor can be thinned to a thickness of 18 μm to 70 μm, which is more preferable. When the volume average particle diameter of the phosphor is in the range of 6 μm to 30 μm, the wavelength conversion member containing the phosphor can be thinned to a thickness of 18 μm to 70 μm, which is more preferable. When the volume average particle diameter of the phosphor is in the range of 6 μm to 20 μm, the wavelength conversion member containing the phosphor can be thinned to a thickness of 22 μm to 35 μm, which is even more preferable. When the volume average particle diameter of the phosphor is in the range of 6 μm to 15 μm, the wavelength conversion member containing the phosphor can be thinned to a thickness of 22 μm to 30 μm, which is even more preferable. In addition, a wavelength conversion member containing a phosphor with a volume average particle size in the range of 5 μm to 35 μm can emit light with high luminosity even when the thickness of the wavelength conversion member is reduced. By using a wavelength conversion member that can emit light with high luminosity, the brightness unevenness of the light emitted from the light emitting portion can be further reduced.

In the case of wavelength conversion members having the same area, the thickness of the wavelength conversion member is the volume ratio of each wavelength conversion member. Taking into account the volume ratio of the wavelength conversion member, the amount of phosphor considering the volume of the wavelength conversion member, which is expressed as the product of the thickness of the wavelength conversion member and the content (parts by mass) of the phosphor in the wavelength conversion member relative to 100 parts by mass of the translucent material in the wavelength conversion member, is preferably within the range of 2000 parts by mass to 14000 parts by mass. If the amount of phosphor considering the volume of the wavelength conversion member is within the range of 2000 parts by mass to 14000 parts by mass, even if the thickness of the wavelength conversion member is thin, such as 18 μm to 100 μm, it is possible to emit light with high luminous intensity.
When the thickness of the wavelength conversion member is within the range of 20 μm or more and 70 μm or less, the amount of the phosphor taking into consideration the volume of the wavelength conversion member may be within the range of 2500 parts by mass or more and 13200 parts by mass or less.
When the thickness of the wavelength conversion member is within the range of 22 μm or more and 35 μm or less, the amount of the phosphor taking into consideration the volume of the wavelength conversion member may be within the range of 2500 parts by mass or more and 10000 parts by mass or less.
When the thickness of the wavelength conversion member is within the range of 22 μm or more and 30 μm or less, the amount of phosphor taking into account the volume of the wavelength conversion member may be within the range of 2,500 parts by mass or more and 8,000 parts by mass or less, or may be within the range of 2,600 parts by mass or more and 6,000 parts by mass or less.

When the volume average particle size of the phosphor is within the range of 5 μm or more and 35 μm or less, the wavelength conversion member containing the phosphor can be made thin, with a thickness within the range of 18 μm or more and 100 μm or less, and the amount of phosphor taking into account the volume of the wavelength conversion member, which is expressed as the product of the thickness of a wavelength conversion member having the same area and the content of the phosphor in the wavelength conversion member per 100 parts by mass of the translucent material in the wavelength conversion member, can be within the range of 2,000 parts by mass or more and 14,000 parts by mass or less, and when emitting light having the same dominant wavelength, light with high luminous intensity can be emitted.
When the volume average particle size of the phosphor is within the range of 6 μm or more and 30 μm or less, the wavelength conversion member containing the phosphor can be made thin, with a thickness within the range of 20 μm or more and 70 μm or less, and even when the thickness of the wavelength conversion member is thin, the amount of phosphor taking into account the volume of the wavelength conversion member can be within the range of 2,500 parts by mass or more and 13,200 parts by mass or less, and when emitting light having the same dominant wavelength, it is possible to emit light with high luminous intensity.
When the volume average particle size of the phosphor is within the range of 6 μm or more and 20 μm or less, the wavelength conversion member containing the phosphor can be made thinner, within the range of 22 μm or more and 35 μm or less, and even if the thickness of the wavelength conversion member is thinner, the amount of phosphor taking into account the volume of the wavelength conversion member can be within the range of 2,500 parts by mass or more and 10,000 parts by mass or less, and when emitting light having the same dominant wavelength, it is possible to emit light with high luminous intensity.
When the volume average particle size of the phosphor is within the range of 6 μm or more and 15 μm or less, the wavelength conversion member containing the phosphor can be made thinner, within the range of 22 μm or more and 30 μm or less, and even if the thickness of the wavelength conversion member is thinner, the amount of the phosphor taking into account the volume of the wavelength conversion member can be within the range of 2500 parts by mass or more and 8000 parts by mass or less, more preferably within the range of 2600 parts by mass or more and 6000 parts by mass or less, and when emitting light having the same dominant wavelength, it is possible to emit light with high luminous intensity.

When the wavelength conversion member contains a fourth nitride phosphor (CASN phosphor) represented by the formula (5), if the volume average particle size of the CASN phosphor is within a range of 5 μm or more and 35 μm or less, and if the mass (mg) of the phosphor per area ( ^cm2 ) of the wavelength conversion member is within a range of 1.50 mg/ ^cm2 or more and 9.00 mg/ ^cm2 or less, the thickness can be reduced while suppressing a decrease in luminous intensity.
When the wavelength conversion member contains a CASN phosphor, if the volume average particle size of the CASN phosphor is within the range of 6 μm or more and 30 μm or less, the mass (mg) of the phosphor relative to the area ( ^cm2 ) of the wavelength conversion member can be within the range of 2.00 mg/ ^cm2 or more and 8.50 mg/ ^cm2 or less, and the thickness can be made thin while containing an optimal amount of phosphor (mass: mg) relative to the area, and light with high luminous intensity can be emitted.
When the wavelength conversion member contains a CASN phosphor, and the volume average particle size of the CASN phosphor is within the range of 6 μm or more and 15 μm or less, when the wavelength conversion member does not contain a light diffusing agent, the mass (mg) of the phosphor relative to the area ( ^cm2 ) of the wavelength conversion member can be within the range of 3.00 mg/ ^cm2 or more and 4.00 mg/ ^cm2 or less, and the thickness can be made thin while containing an optimal amount of phosphor relative to the area, and light with high luminance can be emitted.
When the wavelength conversion member contains a CASN phosphor, the volume average particle size of the CASN phosphor is within the range of 6 μm or more and 15 μm or less, and when the wavelength conversion member contains a light diffusing agent, the mass (mg) of the phosphor relative to the area ( ^cm2 ) of the wavelength conversion member can be within the range of 2.00 mg/ ^cm2 or more and 4.00 mg/ ^cm2 or less, and compared to when no light diffusing agent is included, even with a small amount of phosphor relative to the area, the thickness can be made thinner and light with high luminance can be emitted.

The wavelength conversion member preferably includes at least one selected from the group consisting of a first fluoride phosphor (KSF phosphor) having a composition represented by the formula (7) and a second fluoride phosphor (KSAF phosphor) having a composition represented by the formula (8). The KSF phosphor or KSAF phosphor can adjust the afterglow time of the light emitted from the phosphor by changing the elements and molar ratios contained in the composition to adjust the composition. If the afterglow time of the phosphor's emission can be adjusted, a wavelength conversion member containing the phosphor can emit light that looks fantastic. For example, if the afterglow time is long, the outline of the light emission part becomes blurred, and the light at the light extraction part tends to look fantastic. The afterglow time can be measured by irradiating the phosphor with excitation light and blocking the irradiation of the excitation light as a reference time, measuring the change over time in the emission intensity of the light emitted from the phosphor, and setting the emission intensity of the phosphor when irradiated with excitation light as 100% of the reference intensity, and the time when the emission intensity becomes 10% of the reference intensity of 100% can be the afterglow time. The excitation light can be, for example, light with an emission peak wavelength of 450 nm, which can be used to irradiate the phosphor. The emission intensity of the light emitted from the phosphor can be measured using a spectrophotometer (for example, product name F-7000, manufactured by Hitachi High-Technologies Corporation).

The afterglow time of the KSF or KSAF phosphor is preferably adjusted to a range of 5 ms to 20 ms. If the afterglow time of the phosphor is within the range of 5 ms to 20 ms, the outline of the light emitting portion becomes blurred, and a more fantastical irradiation light can be emitted.
In the KSF phosphor, when the element ^A1 is K and the element ^M6 is Si in the composition represented by the formula (7), the afterglow time of the phosphor can be set to 13 ms by changing the element ^M6 to Ge, for example.
In the KSF phosphor, when the element ^A1 is K and the element ^M6 is Si in the composition represented by the formula (7), the afterglow time of the phosphor can be set to 9 ms by, for example, changing the element ^A1 to Na and the element ^M6 to Ge.
In the KSF phosphor, when the element ^A1 is K and the element ^M6 is Si in the composition represented by the formula (7), the afterglow time of the phosphor can be set to 7 ms by, for example, changing the element ^A1 to Cs and the element ^M6 to Ti.
In the KSAF phosphor, when the element ^A2 is K, the element ^M7 is Si, and the element ^M8 is Al in the composition represented by the formula (8), the afterglow time of the phosphor can be set to 13 ms by changing the element ^M7 to Ge, for example.
In the KSAF phosphor, when the element ^A2 is K, the element ^M7 is Si, and the element ^M8 is Al in the composition represented by the formula (8), the afterglow time of the phosphor can be set to 9 ms by, for example, changing the element ^A2 to Na and the element ^M7 to Ge.
In the KSAF phosphor, when the element ^A2 is K, the element ^M7 is Si, and the element ^M8 is Al in the composition represented by the formula (8), the afterglow time of the light emission of the phosphor can be set to 7 ms by, for example, changing the element ^A2 to Cs and the element ^M7 to Ti.

Figure 4 shows a schematic side view of an example of a vehicle lamp 10. The vehicle lamp 10 includes a wavelength conversion member 3 that contains at least one type of phosphor 31 and covers the multiple light emitting portions 1a of the light guide plate 1. Both ends of the light guide plate 1 and the wavelength conversion member 3 may be supported by support members 41 and 42, respectively. The light source 2 may be disposed opposite the side surface of the light guide plate 1 and supported by the support member 41 so that the light emitted from the light source 2 enters the light guide plate 1 from the side surface of the light guide plate 1. The vehicle lamp 10 preferably includes a wavelength conversion member 3 that covers the light extraction side of the multiple light emitting portions 1a. The vehicle lamp may include one wavelength conversion member that covers all of the multiple light emitting portions 1a of the light guide plate 1.

The vehicle lamp may include a wavelength conversion member that covers some of the multiple light exit portions of the light guide plate. By including a wavelength conversion member that covers the light extraction side of the multiple light exit portions, the light that enters the light guide plate from the light source at the light exit portion of the light guide plate is diffused and emitted from the light exit portion, and is further diffused by the wavelength conversion member, so that light with reduced brightness unevenness appears to be emitted throughout the entire light exit portion. In addition, by covering all of the multiple light exit portions with one wavelength conversion member, for example, the outline of the light irradiated on each light exit portion becomes blurred, making the light at the light extraction portion appear more fantastical.

Figure 5 shows a schematic side view of an example of a vehicle lamp 10. The vehicle lamp 10 preferably includes a plurality of wavelength conversion members 3 that cover the plurality of light emitting portions 1a on the light guide plate 1. The plurality of wavelength conversion members 3 are arranged on the light guide plate 1 at a distance from the light guide plate 1. The wavelength conversion member 3 includes a phosphor 31 and a phosphor 32 having a composition or emission peak wavelength different from that of the phosphor 31. The plurality of wavelength conversion members 3 may be arranged in direct contact with the upper surface of the light guide plate 1. The vehicle lamp 10 includes a plurality of wavelength conversion members 3 that cover the light extraction sides of the plurality of light emitting portions 1a, so that the light incident on the light guide plate 1 from the light source 2 is diffused and emitted from the light emitting portion 1a, and is further diffused by the wavelength conversion member 3, so that light with reduced luminance unevenness appears to be emitted over the entire area of the light emitting portion 1a. In addition, by arranging each of the multiple wavelength conversion members 3 on each light emitting portion 1a, it is possible to increase the difference in brightness between the brightness on the light emitting portion 1a and the low brightness portion 1b, for example, and improve the contrast. Furthermore, by arranging each wavelength conversion member 3 at a distance, the outline of the light emitted on each light emitting portion 1a becomes easier to see, which makes it easier to improve the design of the light emitted by the vehicle lamp. By making the outline of the light emitted on each light emitting portion easier to see and highlighting the outline of the designed light emitting portion, the light at the light extraction portion can be made to look fantastic.

The vehicle lamp of the second embodiment includes a plurality of light guide plates having light emitting portions, a plurality of light sources that input light having an emission peak wavelength in the range of 420 nm to 550 nm to the light guide plates, and a wavelength conversion member that is disposed on the light emitting portions and converts the wavelength of the light emitted from the light emitting portions to emit light having an emission peak wavelength in the range of 540 nm to 700 nm.

Figure 6A is a schematic plan view showing an example of a vehicle lamp 20 of the second embodiment. Figure 6B is a schematic cross-sectional view of the vehicle lamp 20 shown in Figure 6A as viewed from the direction of the arrow 6B. The vehicle lamp 20 includes a plurality of light guide plates 11 having a light emitting portion 11a, a plurality of light sources 2 that input light having an emission peak wavelength in the range of 420 nm to 550 nm to the light guide plate 11, and a wavelength conversion member 3 that is arranged on the light emitting portion 11a and converts the wavelength of the light emitted from the light emitting portion 11a to emit light having an emission peak wavelength in the range of 540 nm to 700 nm. The wavelength conversion member 3 includes at least one type of phosphor 31. It is preferable that the vehicle lamp 20 includes one wavelength conversion member 3 that covers the plurality of light guide plates 11 in order to emit light with reduced luminance unevenness over the entire area of the light emitting portion 11a. By covering all of the multiple light guide plates 11 with one wavelength conversion member, for example, the outline of the light irradiated on each light guide plate 11 becomes blurred, making the light at the light extraction section appear more fantastical.

Figure 7A is a schematic plan view showing an example of a support member 12 on which a plurality of light guide plates 11 provided in a vehicle lamp of the second embodiment are arranged. Figure 7B is a schematic cross-sectional view of the light guide plate 1 of Figure 7A viewed from the direction of the arrow 7B. A plurality of light guide plates 11 having a light emitting portion 11a are arranged on a support member 12. The support member 12 is, for example, a white member containing a light reflective material. The support member 12 has a recess 12a at the position where the light guide plate 11 is arranged, a protrusion 12b between the recesses 12a and 12a where the light guide plate 11 is arranged, and it is preferable that the support member 12 also has protrusions 12b on both ends. It is preferable that the support member 12 has a recess 12a where the light guide plate 11 is arranged and a protrusion that becomes a low brightness portion 12b between adjacent light guide plates 11, 11. The light guide plate 11 may be one in which the side opposite to the side where it is arranged on the support member 12, i.e., one side on the light extraction side, becomes the light emitting portion 11a. When the support member 12 has a recess 12a and the light guide plate 11 is disposed in the recess 12a, the side of the light guide plate 11 is covered with a convex portion that becomes the low brightness portion 12b. The light guide plate 11, whose side is covered with a convex portion that becomes the low brightness portion 12b, has less light leaking from the side, and can increase the brightness of the light emitted from the light emitting portion 11a. When the vehicle lamp 20 includes a plurality of light guide plates 11, when the plurality of light guide plates 11 are used as a surface light source, the vehicle lamp 20 can partition the area that becomes the light extraction portion where the surface light source is disposed into a plurality of areas by one light emitting portion 11a of one light guide plate 11 and the low brightness portion 12b of the support member 12. In the area that becomes the light extraction portion where the vehicle lamp 20 is disposed so that the plurality of light guide plates 11 and the support member 12 become a surface light source, light may be emitted from one light emitting portion 11a that becomes one section, and light of a different color tone may be emitted for each of the partitioned sections. The support member 12 may be any member capable of holding multiple light guide plates 11, and may be, for example, a known flat substrate. Also, instead of being a white member, the support member 12 may be, for example, a member with a refractive index lower than that of the light guide plates 11. This may result in a low-luminance portion.

In order to emit light with reduced brightness unevenness across the entire area of the light emitting portion 11a, the vehicle lamp preferably includes multiple wavelength conversion members covering the light extraction side of each of the multiple light emitting portions. By arranging each wavelength conversion member at a distance, the outline of the light emitted from each light emitting portion 11a becomes easier to see, which makes it easier to improve the design of the light emitted by the vehicle lamp.

8 shows a schematic side view of an example of a vehicle lamp 20. The vehicle lamp 20 includes a plurality of light guide plates 11 arranged on a support member 12 having a low luminance portion 12b, and a plurality of wavelength conversion members 3 covering the light exit portions 11a of the light guide plates 11.
The wavelength conversion member 3 includes at least one type of phosphor 31 .

The light guide plate in the first embodiment, or the light guide plate and the support member in the second embodiment, are provided with a light output section and a low-brightness section, so that the area from which light is output is divided into a plurality of sections, each section being formed by one light output section, and light can be output for each section. If the area from which light is output from the vehicle lamp is divided into a plurality of sections and light can be output for each divided section, it is possible to display animations such as, for example, outputting light from the right light output section in sequence to the left light output section in a flowing manner to display a message such as "Welcome" or outputting light from the left light output section in sequence to the right light output section in a flowing manner to display a message such as "Good Bye". By displaying animations, the light at the light output section becomes more likely to look fantastic. The area from which light is output from the vehicle lamp is the area that becomes the light output section when the vehicle lamp is mounted on the vehicle as a surface light source, as described later. The area where light is emitted from the vehicle lamp and serves as the light extraction section may be divided into multiple sections, and light of a different color tone may be emitted from each of the divided sections. If the area where light is emitted from the vehicle lamp and serves as the light extraction section when the vehicle lamp is mounted on the vehicle is divided into multiple sections and light of a different color tone is emitted from each of the divided sections, it may be possible to use it as a rear combination lamp that emits, for example, white light for a back-up light (back lamp), red light for both a brake light (stop) and a tail light (tail), and amber light for a turn signal (turn signal).

It is preferable that the vehicle lamp includes a diffusion plate arranged on the light extraction side of the wavelength conversion member and/or a diffusion plate arranged on the opposite side of the light extraction side of the wavelength conversion member. When a diffusion plate is arranged on the light extraction side of the wavelength conversion member, the light emitted from the wavelength conversion member is further diffused by the diffusion plate, and light with reduced luminance unevenness is emitted. Also, when a diffusion plate is arranged on the opposite side of the light extraction side of the wavelength conversion member, the light emitted from the light output part is diffused by the diffusion plate before entering the wavelength conversion member and is then entered into the wavelength conversion member, and the light is further diffused by the wavelength conversion member, and light with reduced luminance unevenness is emitted. The diffusion plate may be one diffusion plate arranged on either the light extraction side of the wavelength conversion member or the opposite side of the light extraction side of the wavelength conversion member, or two diffusion plates may be arranged on both. The diffusion plate may be a diffusion layer formed in contact with the surface of the light extraction side of the wavelength conversion member and/or the surface opposite the light extraction side. The diffusion plate refers to a plate-shaped, sheet-shaped, or layer-shaped member containing a translucent material and a light diffusing agent. The light-transmitting material may be at least one selected from the group consisting of resin, glass, and inorganic material. The resin used in the light-transmitting material is preferably at least one selected from the group consisting of epoxy resin, silicone resin, phenol resin, and polyimide resin. The inorganic material used in the light-transmitting material may be at least one selected from the group consisting of aluminum oxide and aluminum nitride. The light diffusing agent used in the diffusion plate may be titanium oxide, aluminum oxide, silicon oxide, zinc oxide, etc.

Figure 9 shows a schematic side view of an example of a vehicle lamp 10. The vehicle lamp 10 has a wavelength conversion member 3 on the light output portion 1a of the light guide plate 1, and a diffusion plate 4 on the side opposite the light extraction side of the wavelength conversion member 3. In Figures 9 and 10, the light extraction side or light extraction direction refers to the +z direction in the figures.

The vehicle lamp preferably includes a prism sheet disposed on the light extraction side of the wavelength conversion member. The prism sheet refracts light incident from various directions in a direction toward the light extraction side, i.e., in a direction perpendicular to the light output side surface of the light guide plate and the light output side surface of the wavelength conversion member. As a result, light containing many light components perpendicular to the prism sheet is output from the light output side surface of the prism sheet, thereby increasing the brightness of the light and reducing the brightness unevenness of one light output section. The thickness of the prism sheet is, for example, about 0.08 μm. For example, an advanced structural optical composite (ASOC) manufactured by 3M can be used as the prism sheet. The prism sheet may be disposed on the light extraction side of the wavelength conversion member at a distance from the wavelength conversion member, or may be disposed so as to be in direct contact with the wavelength conversion member. When a diffusion plate is disposed on the light extraction side of the wavelength conversion member, the prism sheet may be disposed at a distance from the diffusion plate, or may be disposed so as to be in direct contact with the diffusion plate.

The vehicle lamp preferably includes a reflective layer disposed on the opposite side of the light extraction side of the light output section of the light guide plate. By providing a reflective layer disposed on the opposite side of the light output section of the light guide plate, the light guided through the light guide plate is reflected by the reflective layer, and the component of the light output from the light output section to the light output side is increased, thereby increasing the brightness of the light output from the light output section. The reflective layer may be formed in contact with the surface of the light output section of the light guide plate opposite the light extraction side. The reflective layer may be a reflector that can be disposed at a distance from the surface of the light output section of the light guide plate opposite the light extraction side. The reflective layer includes a light-transmitting material and a reflector. The light-transmitting material used in the reflective layer is preferably a resin. Examples of the resin used in the light-transmitting material include curable resins mainly composed of acrylate resin, epoxy resin, etc. Examples of the reflective material used in the reflective layer or reflector include particles of oxides such as titanium oxide, aluminum oxide, silicon oxide, and zinc oxide.

The vehicle lamp preferably includes a dichroic mirror disposed on the light extraction side of the wavelength conversion member. By providing the dichroic mirror on the light extraction side of the wavelength conversion member, it is possible to transmit light of a predetermined wavelength among the light emitted from the wavelength conversion member, and to emit light of a desired color tone from the light extraction side. The dichroic mirror is formed of a dielectric multilayer film having _a predetermined wavelength selectivity. The dielectric multilayer film may be formed of _Ta2O5 / _SiO2 , _TiO2 / _SiO2 , _Nb2O5 / _{SiO2 ,} or the like.

The diffuser plate, prism sheet, reflective layer, and dichroic mirror can be used in any combination.

Figure 10 shows a schematic side view of an example of a vehicle lamp 10. The vehicle lamp 10 includes a wavelength conversion member 3 on the light output portion 1a of the light guide plate 1, a reflective layer 6 on the side opposite the light extraction side of the wavelength conversion member 3, a diffuser plate 4 on the light extraction side of the wavelength conversion member, a dichroic mirror 7 on the light extraction side of the diffuser plate 4, and a prism sheet 5 on the light extraction side of the dichroic mirror 7.

It is preferable that the vehicle lamp is equipped with a color filter that has a transmittance of 5% or less for light with a wavelength in the range of 400 nm to 500 nm, and a transmittance of 60% or more for light with a wavelength in the range of 610 nm to 700 nm.

The vehicle lamp has a transmittance of 5% or less for light with a wavelength in the range of 400 nm to 500 nm and a transmittance of 60% or more for light with a wavelength in the range of 610 nm to 700 nm, and is equipped with a color filter, thereby suppressing the transmission of light from a light source having an emission peak wavelength in the range of 420 nm to 550 nm and making it easier to transmit light that has been wavelength converted by the wavelength conversion member, making it easier to see the outline of the light that emerges from the light exit section. When the outline of the light that emerges from the light exit section is easier to see, the outline of the designed light exit section is made to stand out, making the light at the light extraction section look fantastic.

The color filter is preferably disposed on the light extraction side of the wavelength conversion member. The color filter can be used in any combination with one or more members selected from the group consisting of a diffusion plate, a prism sheet, a reflective layer, and a dichroic mirror. As described below, the cover of the lamp body may be a color filter.

Next, a procedure for measuring the luminance of a portion facing one light output portion from the light output side of the wavelength conversion member (hereinafter also referred to as "luminance Li of one light output portion") and the luminance of a portion facing a low luminance portion (hereinafter also referred to as "luminance Lo of the low luminance portion"). From the luminance Li of one light output portion and the luminance Lo of the low luminance portion, the average luminance Li _ave of one light output portion and the average luminance Lo _ave of the low luminance portion can be measured by the following procedures (a) to (j). The order of the procedures (a) to (j) can be changed as necessary.
(a) Using a two-dimensional color luminance meter, the luminance of the entire surface of a light guide plate or the entire surface of a support member on which multiple light guide plates are arranged is measured pixel by pixel from the light extraction side of the wavelength conversion member.
(b) At the boundary line between a region facing one light output section (one light output section) and a region other than the region facing one light output section (low brightness section), the brightness near the boundary line of one light output section has the smallest value.
(c) The smallest luminance value near the boundary line of one light exit portion is set as the luminance L _B indicating the boundary line of one light exit portion. When measuring the entire surface of multiple light guide plates or a support member equipped with multiple light guide plates, if the same light exit portion is measured, the value of the luminance L _B indicating the boundary line is set so that the area or number of pixels of the same light exit portion is the same value in the multiple light guide plates.
(d) The luminance of a portion that is equal to or greater than the luminance L _B indicating the set boundary line is set as the luminance Li of one light output portion.
(e) Calculating the total luminance Li _total of the luminance Li of one light output portion measured for each pixel. The total luminance Li _total of one light output portion is the sum of the luminance Li of one light output portion measured for each pixel.
(f) The arithmetic mean value of the total luminance Li _total of one light emitting portion is calculated as the average luminance Li _ave of one light emitting portion.
(g) The luminance of a portion that is less than the luminance L _B value indicating the set boundary line is set as the luminance Lo of the low luminance portion.
(h) Calculate the total luminance Lo _total of the luminance Lo of the low luminance portion measured for each pixel. The total luminance Lo _total of the low luminance portion is the sum of the luminance Lo of the low luminance portion measured for each pixel.
(i) The arithmetic mean value of the total luminance Li _total of the low luminance parts is calculated as the average luminance Lo _ave of the low luminance parts.
(j) The average luminance Li _ave of one light emitting portion is taken as 100%, and the ratio of the average luminance Lo _ave of the low luminance portion (Li _ave /Lo _ave × 100(%)) is calculated.
In this specification, the two-dimensional luminance meter may be, for example, an imaging color luminance meter (ProMetric (registered trademark), manufactured by Radiant Vision Systems).

In the vehicle lamp of the present disclosure, when the average luminance Li _ave of one light output section measured from the light output side of the wavelength conversion member is 100%, the ratio of the average luminance Lo _ave of the low luminance section is preferably 20% or less. In the vehicle lamp of the present disclosure, when the average luminance Li _ave of one light output section is 100%, if the ratio of the average luminance Lo _ave of the low luminance section is 20% or less, light is less likely to leak from the low luminance section, and the area that becomes the light extraction section when the vehicle lamp is arranged as a surface light source can be divided into multiple sections by one light output section and the low luminance section, and light can be emitted for each of the multiple sections. When the average luminance Li _ave of the light output section is 100%, the ratio of the average luminance Lo _ave of the low luminance section may be 20% or less, may be 15% or less, or may be 10% or less. The low luminance portion may not emit light, and the ratio of the average luminance Lo _ave of the low luminance portion to the average luminance Li _ave of the light emitting portion may be 0%. The ratio of the average luminance Lo _ave of the low luminance portion to the average luminance Li _ave of the light emitting portion may be 1% or more, 2% or more, or 5% or more.

Furthermore, the luminance unevenness E of the luminance of one light emitting portion measured from the light extraction side of the wavelength conversion member can be measured by the following steps (k) to (n). The order of steps (k) to (n) can be reversed as necessary.
(k) A difference ΔLi between the luminance Li of one light output portion measured for each pixel and the average luminance Li _ave of the light output portions is calculated by the following formula (I).
(l) The maximum value ΔLi _max of the difference ΔLi is obtained.
(m) The minimum value ΔLi _min of the difference ΔLi is found.
(n) From the average luminance Li _ave of the light output portion, the maximum value ΔLi _max of the differences ΔLi, and the minimum value ΔLi _min of the differences ΔLi, the luminance unevenness E of one light output portion is calculated by the following formula (II).
ΔLi = Li - Li _ave (I)
E = ΔLi _max / Li _ave - ΔLi _min / Li _ave (II)

It is preferable that the luminance unevenness E of one light output section is less than 1.5. If the luminance unevenness E of one light output section is less than 1.5, it is possible to emit light with little luminance unevenness from the light output section, and the light output section can be used as a surface light source with little luminance unevenness. The luminance unevenness E may be 1.4 or less, 1.3 or less, preferably 1.2 or less, more preferably 1.1 or less, and even more preferably 1.0 or less, and may be 0.1 or more, or 0.2 or more.

The number of pixels in a portion facing one light output section measured using the above-mentioned two-dimensional luminance colorimeter varies depending on the size of the light output section, but is within the range of 200,000 pixels (points) to 400,000 pixels (points). The luminance difference ΔLi and luminance unevenness E in a portion facing one light output section measured from the light extraction side of the wavelength conversion member can be determined in accordance with the measurement method for luminance unevenness in the measurement method for organic EL display modules of EIAJ ED-2810 specified by the Japan Electronics and Information Technology Industries Association.

The vehicle lamp preferably comprises a lamp body having a light extraction portion, and a cover disposed on the light extraction portion, and transmits light through the cover within a region R defined by a first R line connecting the first R point and the second R point, a second R line connecting the second R point and the third R point, a third R line connecting the third R point and the fourth R point, and a fourth R line connecting the fourth R point and the first R point, with chromaticity coordinates (x, y) of (x = 0.645, y = 0.335) being the first R point, (x = 0.665, y = 0.335) being the second R point, (x = 0.735, y = 0.265) being the third R point, and (x = 0.721, y = 0.259) being the fourth R point in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram. If a vehicle lamp has a lamp body and a cover, and the light emitted through the cover has a hue within region R in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram, then it can emit red light that can be used for both brake lights (stop) and tail lights (taillights), for example. The light having a hue within region R in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram may be emitted from at least one light emitting portion of the vehicle lamp.

When light within region R in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram is emitted from at least one light emitting portion of the vehicle lamp through the cover, it is preferable to have at least one light source that emits light having an emission peak wavelength in the range of 420 nm to 470 nm. The light source having an emission peak wavelength in the range of 420 nm to 470 nm can be the light emitting element described above.

The vehicle lamp preferably comprises a lamp body having a light extraction portion, and a cover disposed on the light extraction portion, and transmits light through the cover to emit light within an area A defined by a first line A connecting the first A point and the second A point, a second line A connecting the second A point and the third A point, a third line A connecting the third A point and the fourth A point, and a fourth line A connecting the fourth A point and the first A point, with chromaticity coordinates (x, y) of (x = 0.545, y = 0.425) being the first A point, (x = 0.557, y = 0.442) being the second A point, (x = 0.609, y = 0.390) being the third A point, and (x = 0.597, y = 0.390) being the fourth A point in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram. If a vehicle lamp has a lamp body and a cover, and the light emitted through the cover has a color tone within region A in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram, it can emit orange light for a turn signal, for example. The light having a color tone within region A in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram may be emitted from at least one light emitting portion of the vehicle lamp.

When light within region A in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram is emitted from at least one light emitting portion of the vehicle lamp through the cover, it is preferable to have at least one light source that emits light having an emission peak wavelength in the range of 500 nm to 550 nm. The light source having an emission peak wavelength in the range of 500 nm to 550 nm can be the light emitting element described above.

The vehicle lamp comprises a lamp body having a light extraction section and a cover arranged on the light extraction section, and when light passes through the cover, in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram, the chromaticity coordinates (x, y) are (x = 0.310, y = 0.348) as the first W point, (x = 0.453, y = 0.440) as the second W point, (x = 0.500, y = 0.440) as the third W point, and (x = 0.500, y = 0.382) as the fourth W point. It is preferable that the vehicular lamp emits light within a region W defined by a first W line connecting the first W point and the second W point, a second W line connecting the second W point and the third W point, a third W line connecting the third W point and the fourth W point, a fourth W line connecting the fourth W point and the fifth W point, a fifth W line connecting the fifth W point and the sixth W point, and a sixth W line connecting the sixth W point and the first W point. If the vehicular lamp includes a lamp body and a cover, and the light emitted through the cover has a color tone within the region W in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram, then the vehicular lamp can emit white light, for example, as a back-up lamp. Light having a color tone within region A in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram may be emitted from at least one light emitting portion of the vehicle lamp.

When light within region A in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram is emitted from at least one light emitting portion of the vehicle lamp through the cover, it is preferable to have at least one light source that emits light having an emission peak wavelength in the range of 470 nm to 500 nm. The light source having an emission peak wavelength in the range of 470 nm to 500 nm can be the light emitting element described above.

Figure 11 is a diagram showing regions R, A, and W of light emitted by a vehicle lamp in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram. In Figure 11, the curved line is the spectrum locus, and the numerical values near the spectrum locus indicate wavelengths. Hereinafter, the "CIE 1931 chromaticity diagram" may be referred to as the "chromaticity diagram," and the "chromaticity coordinates of the CIE 1931 chromaticity diagram" may be referred to as the "chromaticity coordinates." Light in region R on the chromaticity diagram exhibits a red emission color. Light in region A on the chromaticity diagram exhibits an orange emission color. Light in region W on the chromaticity diagram exhibits a white emission color. The light in regions R, A, and W on the chromaticity diagram may be emitted from different regions partitioned in the region that serves as the light extraction portion of the vehicle lamp. Light emitted from one light emitting section may emit red light within region R on the chromaticity diagram, light emitted from another light emitting section may emit orange light within region A on the chromaticity diagram, and white light within region W on the chromaticity diagram may be emitted from a light emitting section different from the light emitting sections that emit red and orange light.

In the chromaticity diagram, light with a color tone within regions R, A, and W conforms to the red color tone of a brake light or tail light, the orange color tone of a turn signal light, and the white color tone of a back-up light as specified by the ECE (Economic Commission for Europe) standard, which is an automobile testing standard established by the Economic Commission of Europe. In the chromaticity diagram, light with a color tone within region W has a chromaticity coordinate within the white region specified by JIS D5500. In the chromaticity diagram, light with a color tone within region A meets the chromaticity coordinate ranges of 0.429≧y≧0.398, z≦0.007 as specified by JIS Z8701. Light with a color tone within region R meets the chromaticity coordinate ranges of y≦0.335, z≦0.008 as specified by JIS Z8701. In addition, it is preferable that the light color reflected by the illumination surface of the vehicle lamp cover be in the same chromaticity range as region R.

An example of a vehicle lamp having a lamp body and a cover will be described with reference to the drawings. FIG. 12 is an external view showing a vehicle lamp 100 having a lamp body and a cover attached to a vehicle body 200. FIG. 13 is a cross-sectional view showing a vehicle lamp 100. In the cross-sectional view of FIG. 13, the +Z direction may be described as the upward direction and the -Z direction may be described as the downward direction unless otherwise specified. In FIG. 13, the upper side or upward direction indicates the light extraction side or light extraction direction.

The vehicle lamp 100 described with reference to Figures 12 and 13 includes a lamp body 8 and a cover 9 at the light extraction portion 8a, which is an opening of the lamp body 8. The lamp body 8 may include a light guide plate 1 supported at both ends by support members 41 and 42, and a wavelength conversion member 3. The cover 9 may be a color filter. The light emitted from one light emission portion 1a of the vehicle lamp 100 is wavelength converted at least by the wavelength conversion member 3 and passes through the cover 9. It is preferable that the light that passes through the cover 9 has a color tone within region R in the chromaticity diagram shown in Figure 11, for example. It is preferable that the color filter has a transmittance of 5% or less for light with a wavelength in the range of 400 nm to 500 nm and a transmittance of 60% or more for light with a wavelength in the range of 610 nm to 700 nm.

The vehicle lamps are used as a set of two symmetrical lamps at the rear of the vehicle body. The vehicle lamps may be embedded in the vehicle body so that the cover, which serves as the light emission surface from the vehicle lamp and the reflection surface of external light, is exposed at the rear of the vehicle body so that the lamps are easily visible in the width direction of the vehicle to which they are attached. It is preferable that the vehicle lamps emit white light LW, red light LR, and orange light LA for each region from the emission surface of the cover. It is also preferable that the vehicle lamps reflect red light from the cover that covers the entire irradiation surface in response to external light. In this specification, orange includes amber. The white light LW is the light of the vehicle's back-up lights, the orange light LA is the light of the turn indicators, and the red light LR is the light of the brake lights and tail lights. Each of these light colors satisfies the chromaticity ranges within areas W, R, and A on the chromaticity diagram, and preferably satisfies the ECE standard for white light for back-up lights, orange light for turn indicator lights, and red color tones for brake lights or tail lights.

The cover may function as a color filter, or may have a function as an outer lens. The cover may be provided to impart a function as a reflector to at least a portion of the illumination surface of the vehicle lamp, and may reflect red light when light is incident on the cover from the outside, and may have a function as a reflector. When the cover functions as a color filter, it is preferable that the transmittance of light having a wavelength in the range of 400 nm to 500 nm is 5% or less, and the transmittance of light having a wavelength in the range of 610 nm to 700 nm is 60% or more.

When the cover also functions as a color filter, it can be made of a transparent resin having the necessary strength, such as an acrylic resin or a polycarbonate resin, colored with a red pigment, such as an azo compound, a cyanine compound, a perylene compound, or a dioxazine compound. The cover also functions as an outer lens and is also called an outer lens, but it may have a lens function or may transmit light with its original light distribution without having a lens function. The cover may have irregularities (lens cuts, microprisms) on the back (inner surface) or front surface so that at least a portion of the area becomes a retroreflector.

The lamp body is a housing with an opening at the light extraction section that serves as the irradiation surface, and constitutes the exterior of the vehicle lamp. The lamp body houses a light guide plate, a wavelength conversion member, and a light source, and a cover is arranged to cover the opening that serves as the light extraction section and supports the cover. The lamp body is preferably a light reflector with a reflective surface on the inner surface. In a vehicle lamp equipped with such a lamp body, outgoing light that has passed through a wavelength conversion member or the like is emitted from at least one light exit section toward the cover, and white light LW, orange light LA, and red light LR that have passed through the cover from the light extraction section are emitted from the rear of the vehicle. The vehicle lamp can emit light for each divided area at the light extraction section, and can emit light of each color tone of white, red, and orange specified by ECE after passing through the cover, and can be used as a rear combination lamp for the vehicle body. In addition, since the vehicle lamp can emit light for each of the multiple divided sections at the light extraction section, it is possible to perform an animation display in which the light is turned on so that each section has a specific meaning.

Embodiments of the present disclosure include the following vehicle lamps:

[Item 1]
a light guide plate having a plurality of light emitting portions and low luminance portions located between adjacent light emitting portions and emitting light having a luminance lower than that of light emitted from the light emitting portions;
A plurality of light sources that input light having an emission peak wavelength in the range of 420 nm to 550 nm to the light guide plate;
a wavelength conversion member disposed on the light emitting portion and configured to convert the wavelength of the light emitted from the light emitting portion and emit light having an emission peak wavelength in the range of 540 nm or more and 700 nm or less.
[Item 2]
A plurality of light guide plates each having a light exit portion;
A plurality of light sources that input light having an emission peak wavelength in the range of 420 nm to 550 nm to the light guide plate;
a wavelength conversion member that is disposed on the light emitting portion and converts the wavelength of the light emitted from the light emitting portion to emit light having an emission peak wavelength in the range of 540 nm or more and 700 nm or less.
[Item 3]
3. The vehicle lamp according to claim 2, further comprising a support member for arranging the light guide plate, the support member having a low-brightness portion located between one light guide plate and another light guide plate other than the one light guide plate.
[Item 4]
Item 4. The vehicular lamp according to item 1 or 3, wherein the luminance of a portion of the wavelength conversion member facing one of the light output portions from the light extraction side is measured pixel by pixel using a two-dimensional color luminance meter, and when an average luminance Li _ave of the light output portion, which is an arithmetic average value of the total luminance of the luminance measured for each pixel, is taken as 100%, the average luminance Lo _ave of the low luminance portion, which is the arithmetic average value of the total luminance of the luminance measured for each pixel, is 20% or less.
[Item 5]
5. The vehicular lamp according to any one of claims 1 to 4, further comprising a wavelength conversion member covering a light extraction side of the plurality of light emitting portions.
[Item 6]
5. The vehicular lamp according to any one of claims 1 to 4, further comprising a plurality of wavelength conversion members covering respective light extraction sides of the plurality of light emitting portions.
[Item 7]
7. The vehicular lamp according to claim 1, wherein the luminance of a portion of the wavelength conversion member facing one of the light output portions is measured for each pixel using a two-dimensional color luminance meter, and an average luminance Li _ave of the light output portion, which is an arithmetic average value of a total luminance of the luminance Li of the light output portion measured for each pixel, and a difference ΔLi between the luminance Li and the average luminance Li _ave are calculated by the following formula (I), and a luminance unevenness E calculated by the following formula (II) using a maximum value ΔLi _max of the difference ΔLi, a minimum value ΔLi _min of the difference ΔLi, and the average luminance Li _ave is less than 1.5.
ΔLi = Li - Li _ave (I)
E = ΔLi _max / Li _ave - ΔLi _min / Li _ave (II)
[Item 8]
Item 8. The vehicle lamp according to any one of items 1 to 7, further comprising a diffusion plate disposed on a light extraction side of the wavelength conversion member, and/or a diffusion plate disposed on an opposite side to the light extraction side of the wavelength conversion member.
[Item 9]
Item 9. The vehicle lamp according to any one of items 1 to 8, further comprising a prism sheet disposed on a light extraction side of the wavelength conversion member.
[Item 10]
Item 10. The vehicle lamp according to any one of items 1 to 9, further comprising a reflective layer disposed on an opposite side to a light extraction side of the light emitting portion.
[Item 11]
Item 11. The vehicular lamp according to any one of items 1 to 10, further comprising a dichroic mirror disposed on an opposite side to a light extraction side of the light emitting portion.
[Item 12]
Item 12. The vehicular lamp according to any one of items 1 to 11, wherein the thickness of the wavelength conversion member is within a range of 18 μm to 100 μm.
[Item 13]
The wavelength conversion member includes at least one phosphor selected from the group consisting of a rare earth aluminate phosphor having a composition represented by the following formula (1), a first nitride phosphor having a composition represented by the following formula (2), a second nitride phosphor having a composition represented by the following formula (3), a third nitride phosphor having a composition represented by the following formula (4), a fourth nitride phosphor having a composition represented by the following formula (5), a fifth nitride phosphor having a composition represented by the following formula (6), a first fluoride phosphor having a composition represented by the following formula (7), and a second fluoride phosphor having a composition represented by the following formula (8). The vehicular lamp according to any one of items 1 to 12,
^R13 ( _{AlcGab ) 5O12 : Cea} ( ₁ )
(In formula (1), ^R1 is at least one selected from the group consisting of Y, Gd, Lu, and Tb, and a, b, and c satisfy 0<a≦0.22, 0≦b≦0.4, 0<c≦1.1, and 0.9≦b+c≦1.1.)
M ¹ _d Si _{12-(e + f)} Al _{e + f} O _f N _16-f : Eu (2)
(In formula (2), ^M1 contains at least one element selected from the group consisting of Li, Mg, Ca, Sr, Y, and lanthanoid elements (excluding La and Ce), and d, e, and f respectively satisfy 0<d≦2.0, 2.0≦e≦6.0, and 0≦f≦1.0.)
^M22Si5N8 _: Eu _{( 3} )
(In formula (3), ^M2 is an alkaline earth metal element including at least one selected from the group consisting of Ca, Sr, and Ba.)
Sr _g C a _h A l _i S _{i j} N _k : Eu (4)
(In formula (4), g, h, i, j, and k respectively satisfy 0≦g<1, 0<h≦1, g+h≦1, 0.9≦i≦1.1, 0.9≦j≦1.1, and 2.5≦k≦3.5.)
_CaAlSiN3 :Eu (5)
^M3mM4nAl3 _- ^pSipNq _: ^M5 _{( 6 )}
(In formula (6), ^M3 is at least one element selected from the group consisting of Ca, Sr, Ba, and Mg, ^M4 is at least one element selected from the group consisting of Li, Na, and K, ^M5 is at least one element selected from the group consisting of Eu, Ce, Tb, and Mn, and m, n, p, and q each satisfy 0.80≦m≦1.05, 0.80≦n≦1.05, 0≦p≦0.5, and 3.0≦q≦5.0, respectively.)
A ¹ _s [M ⁶ _r Mn ^{4 +} _r F _t ] (7)
(In the formula (7), A ¹ is at least one element selected from the group consisting of K ⁺ , Li ⁺ , Na ⁺ , Rb ⁺ , Cs ⁺ and NH ₄ ⁺ , M ⁶ is at least one element selected from the group consisting of Group 4 elements and Group 14 elements, r satisfies 0<r<0.2, s is the absolute value of the charge of the [M ⁶ _1-r Mn ⁴⁺ _r F _t ] ion, and t satisfies 5<t<7.)
A ² _w [M ⁷ _1-u-v M ⁸ _v Mn ^{4 +} _u F _x ] (8)
(In the formula (8), A ² is at least one element selected from the group consisting of K ⁺ , Li ⁺ , Na ⁺ , Rb ⁺ , Cs ⁺ and NH ₄ ⁺ , M ⁷ is at least one element selected from the group consisting of Group 4 and Group 14, M ⁸ is at least one element selected from the group consisting of Group 13, u satisfies 0<u<0.2, w is the absolute value of the charge of the [M ⁷ _1-u-v M ⁸ _v Mn ⁴⁺ _u F _x ] ion, v satisfies 0<v≦0.1, and x satisfies 5<x<7.)
[Item 14]
A lamp body having a light extraction portion;
A cover disposed on the light extraction portion,
Item 14. The vehicular lamp according to any one of items 1 to 13, wherein the light is transmitted through the cover and emitted within a region R defined by a first R line connecting the first R point and the second R point, a second R line connecting the second R point and the third R point, a third R line connecting the third R point and the fourth R point, and a fourth R line connecting the fourth R point and the first R point, in which chromaticity coordinates (x, y) in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram are (x = 0.645, y = 0.335), (x = 0.665, y = 0.335), (x = 0.735, y = 0.265), and (x = 0.721, y = 0.259) as a chromaticity coordinate.
[Item 15]
Item 15. The vehicular lamp according to item 14, wherein the at least one light source emits light having an emission peak wavelength in the range of 420 nm to 470 nm.
[Item 16]
A lamp body having a light extraction portion;
A cover disposed on the light extraction portion,
Item 16. The vehicular lamp according to any one of items 1 to 15, wherein the light is transmitted through the cover and emitted within an area A defined by a first line A connecting the first point A and the second point A, a second line A connecting the second point A and the third point A, a third line A connecting the third point A and the fourth point A, and a fourth line A connecting the fourth point A and the first point A, in which chromaticity coordinates (x, y) in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram are (x = 0.545, y = 0.425) as a first point A, (x = 0.557, y = 0.442) as a second point A, (x = 0.609, y = 0.390) as a third point A, and (x = 0.597, y = 0.390) as a fourth point A, and the first line A connecting the second point A and the third point A, the third line A connecting the third point A and the fourth point A, and the fourth line A connecting the fourth point A and the first point A.
[Item 17]
17. The vehicular lamp according to claim 16, wherein the at least one light source emits light having an emission peak wavelength in the range of 500 nm to 550 nm.
[Item 18]
A lamp body having a light extraction portion;
A cover disposed on the light extraction portion,
When passing through the cover, the chromaticity coordinates (x, y) in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram are (x=0.310, y=0.348) as the first W point, (x=0.453, y=0.440) as the second W point, (x=0.500, y=0.440) as the third W point, (x=0.500, y=0.382) as the fourth W point, (x=0.443, y=0.382) as the fifth W point, and (x=0.310, y=0.28 3) is a 6th W point, and light is emitted within an area W defined by a first W line connecting the first W point and the second W point, a second W line connecting the second W point and the third W point, a third W line connecting the third W point and the fourth W point, a fourth W line connecting the fourth W point and a fifth W point, a fifth W line connecting the fifth W point and the sixth W point, and a sixth W line connecting the sixth W point and the first W point.
[Item 19]
Item 19. The vehicular lamp according to item 18, wherein the at least one light source emits light having an emission peak wavelength in the range of 470 nm to 500 nm.
[Item 20]
Item 14. The vehicular lamp according to item 13, wherein the volume average particle diameter of the phosphor is within a range of 5 μm to 35 μm.
[Item 21]
21. The vehicular lamp according to item 13 or 20, wherein an amount of phosphor per volume of the wavelength conversion member, expressed as the product of a thickness of a wavelength conversion member having the same area and a content (parts by mass) of the phosphor in the wavelength conversion member per 100 parts by mass of a translucent material in the wavelength conversion member, is within a range of 2000 parts by mass or more and 14000 parts by mass or less.
[Item 22]
Item 22. The vehicular lamp according to any one of items 1 to 21, comprising a color filter having a transmittance of 5% or less for light having a wavelength in the range of 400 nm or more and 500 nm or less, and a transmittance of 60% or more for light having a wavelength in the range of 610 nm or more and 700 nm or less.

The present disclosure will be specifically explained below using examples. Note that the present disclosure is not limited to these examples.

Example 1
A light guide plate 1 made of polymethyl methacrylate resin (PMMA) having a plurality of light emitting portions 1a and low brightness portions 1b shown in FIG. 3A and FIG. 3B was prepared. A semiconductor light emitting element using a nitride semiconductor that emits light with an emission peak wavelength of 450 nm was prepared as a light source. A wavelength conversion member having a thickness of 60 μm, containing a CASN phosphor having a composition represented by the formula (5) and a silicone resin, was prepared. A vehicle lamp 10 was formed, which includes a light guide plate 1 having a plurality of light emitting portions 1a and low brightness portions 1b located between adjacent light emitting portions 1a shown in FIG. 1A, a light source 2 having an emission peak wavelength of 450 nm, and a wavelength conversion member 3 that is arranged on the light emitting portion 1a so as to cover the light emitting portion 1a and converts the wavelength of the light emitted from the light emitting portion 1a to emit light having an emission peak wavelength of 660 nm. Using a luminance measuring device described later, the chromaticity coordinates (x, y) in the CIE chromaticity diagram of the light emitted from one light emitting portion 1a of the vehicle lamp 10 according to Example 1 were measured for each pixel from the light extraction side of the wavelength conversion member 3. The arithmetic average value of the chromaticity coordinates (x, y) measured for each pixel was calculated. The chromaticity coordinates (average value) of the light emitted from one light emitting portion 1a of the vehicle lamp 10 according to Example 1 measured from the light extraction side of the wavelength conversion member 3 was (x=0.695, y=0.305), and the light was emitted in the region R in the CIE chromaticity diagram shown in FIG. 11.

Example 2
A light guide plate 1 made of polymethyl methacrylate resin (PMMA) having a plurality of light emitting portions 1a and low brightness portions 1b shown in FIG. 3A and FIG. 3B was prepared. A semiconductor light emitting element using a nitride semiconductor that emits light with an emission peak wavelength of 450 nm was prepared as a light source. A wavelength conversion member having a thickness of 60 μm, containing a CASN phosphor having a composition represented by the formula (5) and a silicone resin, was prepared. A vehicle lamp 10 was formed, which includes a light guide plate 1 having a plurality of light emitting portions 1a and low brightness portions 1b located between adjacent light emitting portions 1a as shown in FIG. 9, a light source 2 having an emission peak wavelength of 450 nm, a wavelength conversion member 3 that is arranged on the light emitting portion 1a so as to cover the light emitting portion 1a and converts the wavelength of the light emitted from the light emitting portion 1a to emit light having an emission peak wavelength of 660 nm, and a diffusion plate 4 on the opposite side of the light extraction side of the wavelength conversion member 3. In the same manner as in Example 1, the average value of the chromaticity coordinates (x, y) in the CIE chromaticity diagram of the light emitted from one light emitting portion 1a of the vehicle lamp 10 according to Example 2 was measured. The chromaticity coordinates (average value) of the light emitted from one light emitting portion 1a measured from the light extraction side of the wavelength conversion member 3 of the vehicle lamp 10 according to Example 2 was (x=0.696, y=0.304), and the light was emitted in the region R in the CIE chromaticity diagram shown in FIG.

Comparative Example 1
A light guide plate made of polymethyl methacrylate resin (PMMA) having a plurality of light emitting parts and a low brightness part was prepared. A semiconductor light emitting element emitting light with an emission peak wavelength of 630 nm was prepared as a light source. A vehicle lamp was formed including a light guide plate having a plurality of light emitting parts and a low brightness part located between adjacent light emitting parts, a light source that inputs light having an emission peak wavelength of 630 nm into the light guide plate, and a diffusion plate arranged on the light emitting part so as to cover the light emitting part. Comparative Example 1 differs from Examples 1 and 2 in that a light source having an emission peak wavelength of 630 nm is used instead of a wavelength conversion member that emits light having an emission peak wavelength of 660 nm. In the same manner as in Example 1, the average value of chromaticity coordinates (x, y) in the CIE chromaticity diagram of light emitted from one light emitting part of the vehicle lamp according to Comparative Example 1 was measured. The chromaticity coordinates (average value) of the light emitted from one light exit portion measured from the light extraction side of the diffusion plate of the vehicle lamp in Comparative Example 1 were (x = 0.686, y = 0.314), and the light emitted was in region R in the CIE chromaticity diagram shown in Figure 11.

Measurement of luminance and luminance unevenness Light was emitted from one light output part of each vehicle lamp of Example 1, Example 2, and Comparative Example 1, and the luminance of the part facing the entire surface of the light guide plate from the light extraction side of the wavelength conversion member was measured for each pixel using an imaging color luminance meter (ProMetric (registered trademark), manufactured by Radiant Vision Systems), which is a two-dimensional color luminance meter. The luminance at which the luminance near the boundary between the part facing a specific light output part of the wavelength conversion member and the part facing the low luminance part is the smallest value was set as the luminance L _B of the boundary line. Each vehicle lamp of Example 1, Example 2, and Comparative Example 1 was designed to emit light from a light output part of the same shape, and in each vehicle lamp, the luminance L _B near the boundary line was set so that the area of one light output part was the same area. The arithmetic average value of the total luminance that is equal to or greater than the luminance L _B that is the boundary line was derived as the average luminance Li _ave of the light output part. The arithmetic mean value of the total luminance of the luminances that are less than the boundary luminance L _B was derived as the average luminance Lo _ave of the low luminance portion. Specifically, the measurement was performed according to the above-mentioned procedures (a) to (j). In Example 1, the number of pixels (number of measurement points) of the light exit portion was about 312,000 pixels (number of points).
The ratio of the average luminance Lo _ave of the low luminance portion to the average luminance Li _ave of the light emitting portion, which was taken as 100%, was calculated (Lo _ave /Li _ave × 100(%)).
In addition, the difference ΔLi between the luminance Li of the light output portion measured for each pixel and the average luminance Li _ave of the light output portion was calculated by the following formula (I), and the luminance unevenness E calculated by the following formula (II) was measured using the maximum value ΔLi _max of the difference ΔLi, the minimum value ΔLi _min of the difference ΔLi, and the average luminance Li _ave of the light output portion. Specifically, the measurement was performed according to the above-mentioned procedures (k) to (n). The results are shown in Table 1.
ΔLi = Li - Li _ave (I)
E = ΔLi _max / Li _ave - ΔLi _min / Li _ave (II)

Figure 14 is an external photograph of one light output section from which light is output in a vehicle lamp according to Example 1, taken from the light extraction side of the wavelength conversion member. Figure 15 shows the luminance of a portion of a section facing one light output section and a portion facing a low luminance section, measured for each pixel from the light extraction side of the wavelength conversion member, in a vehicle lamp according to Example 1. Figure 16 shows the luminance of a portion of a section facing one light output section, measured for each pixel from the light extraction side of the wavelength conversion member, in a vehicle lamp according to Example 1.

In the vehicle lamps according to Examples 1 and 2, the ratio of the average luminance Lo _ave of the low luminance portion to the average luminance Li _ave of the light output portion is 20% or less, the light extraction portion is divided into a plurality of portions, and light is output from each of the divided regions. In addition, the vehicle lamps according to Examples 1 and 2 have a luminance unevenness E of less than 1.5, and light with reduced luminance unevenness can be output from the light output portion, which is one of the regions obtained by dividing the light output portion into a plurality of portions. The vehicle lamp according to Example 1 does not include a diffusion plate, but the light output from the light output portion is diffused by the wavelength conversion member, and light with reduced luminance unevenness is output from one light output portion compared to the vehicle lamp according to Comparative Example 1, which includes a diffusion plate. In the vehicle lamp according to Example 2, a diffusion plate is arranged on the light output side of the wavelength conversion member, so that the light output from the wavelength conversion member is further diffused by the diffusion plate, and light with further reduced luminance unevenness is output.

The vehicle lamp of Comparative Example 1 does not have a light source with an emission peak wavelength in the range of 420 nm to 550 nm, so the luminance unevenness E of the light emitted from one light emitting part exceeded 1.5.

As shown in FIG. 14, the vehicle lamp according to the first embodiment can emit light with reduced luminance unevenness from the light emission section that forms a section obtained by dividing the area of the light extraction section into a plurality of sections, and therefore can emit light from each of the plurality of sections in the light extraction section. If light can be emitted from each of the divided sections, it is possible to perform an animation display in which light is turned on to have a specific meaning for each section. In addition, if light of a different color tone can be emitted from each of the divided sections, it can be used in a rear combination lamp that emits white light for a back lamp, red light for both a brake lamp and a tail lamp, and amber light for a turn signal.

From the luminance of each portion of the light guide plate measured for each pixel from the light extraction side of the wavelength conversion member shown in Fig. 15, the luminance L _B which is the smallest value indicating the boundary between the light output portion and low luminance was derived, and each luminance less than the luminance L _B was deleted, and each luminance Li equal to or greater than the luminance L _B was left. Then, as shown in Fig. 16, each luminance Li remained in the same shape as the light output portion, and the average luminance Li _ave of the light output portion, the difference ΔLi, the maximum value ΔLi _max of the difference ΔLi, and the minimum value ΔLi _min of the difference ΔLi of the total luminance Li of the light output portion could be calculated.

Examples 3 to 9
Wavelength conversion members of Examples 3 to 9 were prepared, each containing a CASN phosphor having a composition represented by formula (5) and a silicone resin, and having a thickness shown in Table 2. The volume average particle size of each CASN phosphor used in each wavelength conversion member of each Example, and the parts by mass of the CASN phosphor per 100 parts by mass of the silicone resin are shown in Table 2. The following measurements described below were performed on each wavelength conversion member of the Examples.

Examples 10 to 16
Each wavelength conversion member of Examples 10 to 16 was prepared using a CASN phosphor having a composition represented by formula (5), silicone resin, and aluminum oxide particles as a light diffusing agent, with a thickness shown in Table 2. The volume average particle size of each CASN phosphor used in each wavelength conversion member of each Example, and the parts by mass of the CASN phosphor per 100 parts by mass of the silicone resin are shown in Table 2. The following measurements described below were performed on each wavelength conversion member of the Examples. The aluminum oxide particles serving as a light diffusing agent had a catalog value volume average particle size measured by a laser diffraction method that was in the range of more than 0.4 μm and 0.5 μm or less, and the purity of the aluminum oxide was 99.99 mass% or more.

The following measurements were performed on each of the wavelength conversion members according to Examples 3 to 16. The results are shown in Table 2. In Table 2, the symbol "-" indicates that the corresponding item does not exist, specifically, that the wavelength conversion member does not contain a light diffusing agent.

The volume average particle size of the phosphor used in each wavelength conversion member in the examples was the cumulative 50% particle size from the small diameter side in the volume-based particle size distribution. The volume-based particle size distribution of the phosphor was measured using a laser diffraction particle size distribution measuring device (Master Sizer 3000, manufactured by Malvern Panalytical).

Since each wavelength conversion member in the examples has the same area but a different thickness, the amount of phosphor taking into account the volume of the wavelength conversion member was calculated as the product of the thickness of each wavelength conversion member and the content (parts by mass) of phosphor per 100 parts by mass of silicone resin, which is the light-transmitting member, assuming the area to be 1. Specifically, the amount of phosphor taking into account the volume of the wavelength conversion member was calculated using the following formula (III).
Amount of phosphor taking into account wavelength conversion member=1 (μm ² )×thickness of wavelength conversion member (μm)×amount of phosphor per 100 parts by mass of light-transmitting member (parts by mass) (III)

Chromaticity coordinates before transmission through color filter Each wavelength conversion member of the examples was irradiated with excitation light having an emission peak wavelength of 449 nm, and the emission spectrum of each wavelength conversion member at room temperature (25° C.) was measured using a multichannel spectrometer (PMA-11, manufactured by Hamamatsu Photonics K.K.). From the emission spectrum data of each wavelength conversion member, the chromaticity coordinates (x, y) in the CIE (Commission Internationale de l'Eclairage) 1931 color system were calculated.

Chromaticity coordinates after passing through a color filter, dominant wavelength (λd)
For each wavelength conversion member of the embodiment, the transmittance of light in the wavelength range of 400 nm to 500 nm is 0%, and the transmittance of light in the wavelength range of 610 nm to 700 nm is 60% or more. Using the transmittance curve data of the color filter, the emission spectrum of each wavelength conversion member after passing through the color filter arranged on the light extraction side of the wavelength conversion member was obtained by simulation. From the emission spectrum data of each wavelength conversion member obtained, the value of the chromaticity coordinate (x, y) in the CIE1931 color system of the light emitted from each wavelength conversion member after passing through the color filter was obtained. In addition, from the emission spectrum data of each wavelength conversion member obtained, the dominant wavelength (λd) of the light emitted from each wavelength conversion member after passing through the color filter was obtained. The dominant wavelength (λd) is the wavelength at the point where a line connecting the chromaticity coordinates (x = 0.3333, y = 0.3333) of white light and the chromaticity coordinates (x, y) of the light emitted from each wavelength conversion member after passing through a color filter intersects with the spectral locus in the CIE 1931 color system.

Relative luminous intensity For each wavelength conversion member of the examples, excitation light having an emission peak wavelength of 449 nm was irradiated, and the emission spectrum of each wavelength conversion member at room temperature (25 ° C.) was measured using a multichannel spectrometer (PMA-11, manufactured by Hamamatsu Photonics K.K.), and the luminous intensity (cd) of the emission of each wavelength conversion member after passing through a color filter in the case where a color filter is arranged on the light extraction side of the wavelength conversion member was obtained by simulation. For the simulation, data on the transmittance curve of a color filter in which the transmittance of light in the wavelength range of 400 nm to 500 nm is 0%, and the transmittance of light in the wavelength range of 610 nm to 700 nm is 60% or more was used. The luminous intensity of the wavelength conversion member of Example 10 was set to 100%, and the relative luminous intensity (%) of each wavelength conversion member of the examples other than Example 10 was obtained.

Each of the wavelength conversion members according to Examples 3 to 16 converted the wavelength of excitation light having an emission peak wavelength of 449 nm, and emitted light having an emission peak wavelength of 540 nm or more and 700 nm or less before passing through the color filter.
In the wavelength conversion members according to Examples 3 to 16, the volume average particle diameter of the phosphor is in the range of 5 μm to 35 μm, and the thickness of the wavelength conversion member can be thinned to the range of 18 μm to 100 μm. In addition, even when the thickness of the wavelength conversion members according to Examples 3 to 16 is thin, that is, the volume average particle diameter of the phosphor is in the range of 5 μm to 35 μm, so that the amount of the phosphor considering the volume of the wavelength conversion member is in the range of 2000 parts by mass to 14000 parts by mass, and after passing through the color filter, light having a desired dominant wavelength is emitted, and the relative luminous intensity is also relatively high. In addition, the wavelength conversion members according to Examples 3 to 9, which do not contain a light diffusing agent, do not have a large decrease in relative luminous intensity compared to the wavelength conversion members according to Examples 10 to 16, which contain a light diffusing agent, and have the same relative luminous intensity, and even when they do not contain a light diffusing agent, they emit light with a sufficiently high luminous intensity.
In addition, the wavelength conversion members according to Examples 3 to 16 can be thinned so that the volume average particle size of the phosphor is in the range of 5 μm or more and 35 μm or less, and the mass (mg) of the phosphor per area ( ^cm2 ) of the wavelength conversion member is in the range of 1.50 mg/ ^cm2 or more and 9.00 mg/ ^cm2 or less.

In each of the wavelength conversion members according to Examples 4 to 9 and Examples 11 to 16, the volume average particle size of the phosphor was within the range of 6 μm to 30 μm, and the thickness of the wavelength conversion member was within the range of 20 μm to 70 μm. Furthermore, even when the wavelength conversion members according to Examples 4 to 9 and Examples 11 to 16 had a thin thickness of 20 μm to 70 μm, the amount of the phosphor considering the volume of the wavelength conversion member was within the range of 2500 parts by mass to 14000 parts by mass, and after passing through a color filter, light having a desired dominant wavelength was emitted, and compared to Example 3 and Example 10, light with a relative luminous intensity exceeding 100% was emitted, which was a high relative luminous intensity.
In addition, each of the wavelength conversion members according to Examples 4 to 9 and Examples 11 to 16 has a volume average particle size of the phosphor within the range of 6 μm or more and 30 μm or less, and the mass (mg) of the phosphor per area ( ^cm2 ) of the wavelength conversion member is within the range of 2.00 mg/ ^cm2 or more and 8.50 mg/ ^cm2 or less, so that the thickness can be made thin and light with high relative luminous intensity can be emitted.

In each of the wavelength conversion members according to Examples 4 to 6 and Examples 11 to 13, the volume average particle size of the phosphor was within the range of 6 μm to 15 μm, and the thickness of the wavelength conversion member was within the range of 22 μm to 30 μm. Furthermore, even when the wavelength conversion members according to Examples 4 to 6 and Examples 11 to 13 had a thin thickness of 22 μm to 30 μm, the amount of the phosphor considering the volume of the wavelength conversion member was within the range of 2500 parts by mass to 6000 parts by mass, and after passing through a color filter, light having a desired dominant wavelength was emitted, and compared to Example 3 and Example 10, light with a relative luminous intensity exceeding 100% was emitted, which was a high relative luminous intensity.
In addition, in each of the wavelength conversion members according to Examples 4 to 6, the volume average particle size of the phosphor is within the range of 6 μm or more and 15 μm or less, and when no light diffusing agent is contained, the mass (mg) of the phosphor relative to the area ( ^cm2 ) of the wavelength conversion member can be within the range of 3.00 mg/ ^cm2 or more and 4.00 mg/ ^cm2 or less, the thickness can be reduced, and light with high relative luminous intensity can be emitted.
Furthermore, in each of the wavelength conversion members according to Examples 11 to 13, the volume average particle size of the phosphor is within the range of 6 μm or more and 15 μm or less. Therefore, in the wavelength conversion member containing a phosphor, when a light diffusing agent is included, the mass (g) of the phosphor relative to the area ( ^cm2 ) of the wavelength conversion member can be within the range of 2.00 mg/ ^cm2 or more and 4.00 mg/ ^cm2 or less. Compared to when no light diffusing agent is included, even with a small amount of phosphor relative to the area, the thickness can be reduced and light with high relative luminous intensity can be emitted.

The vehicle lamp of the present disclosure can be used in the rear combination lamps of vehicles used in road vehicles such as motorcycles and four-wheeled vehicles, railway vehicles, and construction machinery such as tractors for leveling, transporting, and loading machines, and excavators for excavation machines.

1: Light guide plate, 1a: Light output section, 1b: Low brightness section, 2: Light source, 3: Wavelength conversion member, 4: Diffuser plate, 5: Prism sheet, 6: Reflective layer, 7: Dichroic mirror, 8: Lamp body, 9: Cover, 10: Vehicle lamp, 11: Light guide plate, 11a: Light output section, 12: Support member, 12b: Low brightness section, 31, 32: Phosphor, 41, 42, 43, 44: Support member, 100: Vehicle lamp, 200: Vehicle body.

Claims (21)

a light guide plate having a plurality of light emitting portions and low luminance portions located between adjacent light emitting portions and emitting light having a luminance lower than that of light emitted from the light emitting portions;
A plurality of light sources that input light having an emission peak wavelength in the range of 420 nm to 550 nm to the light guide plate;
a wavelength conversion member disposed on the light emitting portion and configured to convert the wavelength of the light emitted from the light emitting portion and emit light having an emission peak wavelength in the range of 540 nm or more and 700 nm or less. A plurality of light guide plates each having a light exit portion;
A plurality of light sources that input light having an emission peak wavelength in the range of 420 nm to 550 nm to the light guide plate;
a wavelength conversion member disposed on the light emitting portion and configured to convert the wavelength of the light emitted from the light emitting portion and emit light having an emission peak wavelength in the range of 540 nm or more and 700 nm or less. The vehicle lamp according to claim 2, further comprising a support member for arranging the light guide plate, the support member having a low-brightness portion located between one light guide plate and another light guide plate other than the one light guide plate. 4. The vehicular lamp according to claim 1 or 3, wherein the luminance of a portion of the wavelength conversion member facing one of the light output portions from the light extraction side is measured pixel by pixel using a two-dimensional color luminance meter, and when an average luminance Li _ave of the light output portion, which is an arithmetic average value of a total luminance of the luminance measured for each pixel, is taken as 100%, the average luminance Lo _ave of the low luminance portion, which is an arithmetic average value of a total luminance of the luminance measured for each pixel, is 20% or less. The vehicle lamp according to claim 1 or 2, further comprising a wavelength conversion member that covers the light extraction side of the plurality of light emitting parts. The vehicle lamp according to claim 1 or 2, comprising a plurality of wavelength conversion members each covering the light extraction side of a plurality of the light emitting parts. 3. The vehicular lamp according to claim 1, wherein the luminance of a portion of the wavelength conversion member facing one of the light output portions is measured for each pixel using a two-dimensional color luminance meter, and an average luminance Li _ave of the light output portion, which is an arithmetic average value of a total luminance of the luminance Li of the light output portion measured for each pixel, and a difference ΔLi between the luminance Li and the average luminance Li _ave are calculated by the following formula (I), and a luminance unevenness E calculated by the following formula (II) using a maximum value ΔLi _max of the difference ΔLi, a minimum value ΔLi _min of the difference ΔLi, and the average luminance Li _ave is less than 1.5.
ΔLi = Li - Li _ave (I)
E = ΔLi _max / Li _ave - ΔLi _min / Li _ave (II) The vehicle lamp according to claim 1 or 2, comprising a diffusion plate arranged on the light extraction side of the wavelength conversion member, and/or a diffusion plate arranged on the side opposite the light extraction side of the wavelength conversion member. The vehicle lamp according to claim 1 or 2, further comprising a prism sheet arranged on the light extraction side of the wavelength conversion member. The vehicle lamp according to claim 1 or 2, further comprising a reflective layer disposed on the side opposite the light extraction side of the light emitting portion. The vehicle lamp according to claim 1 or 2, further comprising a dichroic mirror disposed on the opposite side of the light extraction side of the light emitting portion. The vehicle lamp according to claim 1 or 2, wherein the thickness of the wavelength conversion member is in the range of 18 μm to 100 μm. 3. The vehicular lamp according to claim 1 or 2, wherein the wavelength conversion member comprises at least one phosphor selected from the group consisting of a rare earth aluminate phosphor having a composition represented by the following formula (1), a first nitride phosphor having a composition represented by the following formula (2), a second nitride phosphor having a composition represented by the following formula (3), a third nitride phosphor having a composition represented by the following formula (4), a fourth nitride phosphor having a composition represented by the following formula (5), a fifth nitride phosphor having a composition represented by the following formula (6), a first fluoride phosphor having a composition represented by the following formula (7), and a second fluoride phosphor having a composition represented by the following formula (8).
^R13 ( _{AlcGab ) 5O12 : Cea} ( ₁ )
(In formula (1), ^R1 is at least one selected from the group consisting of Y, Gd, Lu, and Tb, and a, b, and c satisfy 0<a≦0.22, 0≦b≦0.4, 0<c≦1.1, and 0.9≦b+c≦1.1.)
M ¹ _d Si _{12-(e + f)} Al _{e + f} O _f N _16-f : Eu (2)
(In formula (2), ^M1 contains at least one element selected from the group consisting of Li, Mg, Ca, Sr, Y, and lanthanoid elements (excluding La and Ce), and d, e, and f respectively satisfy 0<d≦2.0, 2.0≦e≦6.0, and 0≦f≦1.0.)
^M22Si5N8 _: Eu _{( 3} )
(In formula (3), ^M2 is an alkaline earth metal element including at least one selected from the group consisting of Ca, Sr, and Ba.)
Sr _g C a _h A l _i S _{i j} N _k : Eu (4)
(In formula (4), g, h, i, j, and k respectively satisfy 0≦g<1, 0<h≦1, g+h≦1, 0.9≦i≦1.1, 0.9≦j≦1.1, and 2.5≦k≦3.5.)
_CaAlSiN3 :Eu (5)
^M3mM4nAl3 _- ^pSipNq _: ^M5 _{( 6 )}
(In formula (6), ^M3 is at least one element selected from the group consisting of Ca, Sr, Ba, and Mg, ^M4 is at least one element selected from the group consisting of Li, Na, and K, ^M5 is at least one element selected from the group consisting of Eu, Ce, Tb, and Mn, and m, n, p, and q each satisfy 0.80≦m≦1.05, 0.80≦n≦1.05, 0≦p≦0.5, and 3.0≦q≦5.0, respectively.)
A ¹ _s [M ⁶ _r Mn ^{4 +} _r F _t ] (7)
(In the formula (7), A ¹ is at least one ion selected from the group consisting of K ⁺ , Li ⁺ , Na ⁺ , Rb ⁺ , Cs ⁺ and NH ₄ ⁺ , M ⁶ is at least one element selected from the group consisting of Group 4 elements and Group 14 elements, r satisfies 0<r<0.2, s is the absolute value of the charge of the [M ⁶ _1-r Mn ⁴⁺ _r F _t ] ion, and t satisfies 5<t<7.)
A ² _w [M ⁷ _1-u-v M ⁸ _v Mn ^{4 +} _u F _x ] (8)
(In the formula (8), ^A2 is at least one ion selected from the group consisting of K ⁺ , Li ⁺ , Na ⁺ , Rb ⁺ , Cs ⁺ and NH ₄ ⁺ , M ⁷ is at least one element selected from the group consisting of Group 4 and Group 14, M ⁸ is at least one element selected from the group consisting of Group 13, u satisfies 0<u<0.2, w is the absolute value of the charge of the [M ⁷ _1-u-v M ⁸ _v Mn ⁴⁺ _u F _x ] ion, v satisfies 0<v≦0.1, and x satisfies 5<x<7.) A lamp body having a light extraction portion;
A cover disposed on the light extraction portion,
3. The vehicular lamp according to claim 1, wherein the light is transmitted through the cover and emitted within a region R defined by a first R line connecting the first R point and the second R point, a second R line connecting the second R point and the third R point, a third R line connecting the third R point and the fourth R point, and a fourth R line connecting the fourth R point and the first R point, where the chromaticity coordinates (x, y) in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram are (x = 0.645, y = 0.335), (x = 0.665, y = 0.335), (x = 0.735, y = 0.265), and (x = 0.721, y = 0.259), respectively. The vehicle lamp according to claim 14, wherein at least one of the light sources emits light having an emission peak wavelength in the range of 420 nm to 470 nm. A lamp body having a light extraction portion;
A cover disposed on the light extraction portion,
3. The vehicular lamp according to claim 1, wherein the light is transmitted through the cover and emitted within an area A defined by a first line A connecting the first point A and the second point A, a second line A connecting the second point A and the third point A, a third line A connecting the third point A and the fourth point A, and a fourth line A connecting the fourth point A and the first point A, the chromaticity coordinates (x, y) of which are (x=0.545, y=0.425) as a first point A, (x=0.557, y=0.442) as a second point A, (x=0.609, y=0.390) as a third point A, and (x=0.597, y=0.390) as a fourth point A in an xy chromaticity coordinate system of a CIE 1931 chromaticity diagram. The vehicle lamp according to claim 16, wherein at least one of the light sources emits light having an emission peak wavelength in the range of 500 nm to 550 nm. A lamp body having a light extraction portion;
A cover disposed on the light extraction portion,
When passing through the cover, in the xy chromaticity coordinates of the CIE 1931 chromaticity diagram, the chromaticity coordinates (x, y) are (x=0.310, y=0.348) as the first W point, (x=0.453, y=0.440) as the second W point, (x=0.500, y=0.440) as the third W point, (x=0.500, y=0.382) as the fourth W point, (x=0.443, y=0.382) as the fifth W point, and (x=0.310, y=0. 3. The vehicular lamp according to claim 1 or 2, wherein a sixth W point is defined by a first W line connecting the first W point and the second W point, a second W line connecting the second W point and the third W point, a third W line connecting the third W point and the fourth W point, a fourth W line connecting the fourth W point and a fifth W point, a fifth W line connecting the fifth W point and the sixth W point, and a sixth W line connecting the sixth W point and the first W point. The vehicle lamp according to claim 18, wherein at least one of the light sources emits light having an emission peak wavelength in the range of 470 nm to 500 nm. The vehicle lamp according to claim 13, wherein the volume average particle size of the phosphor is in the range of 5 μm to 35 μm. The vehicle lamp according to claim 1 or 2, comprising a color filter having a transmittance of 5% or less for light having a wavelength in the range of 400 nm to 500 nm and a transmittance of 60% or more for light having a wavelength in the range of 610 nm to 700 nm.