Vehicular lighting fixture

Abstract

To provide a vehicular lighting fixture which shows a red color similar to a general red cover part (for example, a general outer lens colored in red) during light extinction of a light-emitting element, and which emits white light from the red cover part during light-emission of the light-emitting element.SOLUTION: A vehicular lighting fixture includes: a first semiconductor light-emitting element having an emission peak wavelength of 470nm-520nm; a second semiconductor light-emitting element having an emission peak wavelength of 580nm-600nm; and a red cover part facing the first semiconductor light-emitting element and the second semiconductor light-emitting element. The red cover part transmits light from the first semiconductor light-emitting element, light from the second semiconductor light-emitting element and red light respectively at a prescribed transmissivity, the first semiconductor light-emitting element and the second semiconductor light-emitting element emit light, and white light is emitted from the red cover part.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to vehicle lamps.

Background Art

[0002] As vehicle lamps, for example, a rear combination lamp can be mentioned. Here, the rear combination lamp includes a brake lamp such as a stop lamp and a brake lamp, a direction indicator such as a turn signal lamp and a wink, a tail lamp, and a back lamp. Further, the rear combination lamp includes a housing and a cover portion (for example, an outer lens) that covers the front side (rear side of the vehicle) of the housing. Further, a red light emission region for a brake lamp and a tail lamp, an orange (amber color) light emission region for a direction indicator, and a white light emission region for a back lamp are provided in the cover portion of the rear combination lamp.

[0003] The cover portion having different color light emission regions as described above is manufactured, for example, by bonding a plurality of plate parts corresponding to each region, or by multi-color molding (for example, two-color molding) a cover base corresponding to the red light emission region and other transparent resin parts.

[0004] However, when the cover portion is manufactured in such a manner, problems such as an increase in the number of plate-like parts corresponding to each region and an increase in assembly man-hours, and a complication of the shape of the mold for molding the cover portion occur. Further, in the cover portion, since the colors of the cover base and the transparent resin portion are different, it is not preferable also in terms of design. An invention for solving such problems is disclosed in Patent Document 1 below.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The invention disclosed in Patent Document 1 relates to an illumination device comprising: a first light-emitting element having an emission peak wavelength of 400 nm to 510 nm; a first phosphor provided at the position where light emitted from the first light-emitting element is incident and having an emission peak wavelength of 485 nm to 700 nm; and a red color filter provided at the position where first light emitted from the first phosphor is incident and transmits a portion of the first light, with a transmittance of 80% or more for light in the 600 nm to 730 nm range and a transmittance of 3% to 50% for light in the 410 nm to 480 nm range, and which emits white light transmitted through the color filter.

[0007] However, referring to Figure 5 of Patent Document 1, the transmittance of light in the 410nm to 480nm range is relatively high in the red color filter (red cover portion), while the transmittance of light in the 500nm to 600nm range is low. Therefore, when the first light-emitting element is extinguished, the portion of the red cover portion corresponding to the white light emission area is thought to exhibit a pinkish-red color.

[0008] Furthermore, the invention disclosed in Patent Document 1 utilizes light emitted from a first phosphor. However, the light emitted from the first phosphor includes a broad wavelength range from blue to orange. As a result, the wavelength range of the light emitted from the first phosphor overlaps with the region of low transmittance in the red cover portion, reducing the amount of light originating from the first phosphor emitted outside the red cover portion. In that case, there is a risk that light of a different color than the intended white light will be emitted from the red cover portion.

[0009] In view of the above-mentioned problems, the objective is to provide a vehicle lighting device in which, when the light-emitting element is extinguished, it exhibits a red color similar to that of a general red cover (for example, a general outer lens colored red), and when the light-emitting element is illuminated, white light is emitted from the red cover. [Means for solving the problem]

[0010] To solve the aforementioned problems, the vehicle lighting device according to the present invention is: A first semiconductor light-emitting element having an emission peak wavelength in the range of 470nm to 520nm, A second semiconductor light-emitting element having an emission peak wavelength of 580nm to 600nm, A red cover portion facing the first semiconductor light-emitting element and the second semiconductor light-emitting element, Equipped with, The red cover portion transmits light from the first semiconductor light-emitting element, light from the second semiconductor light-emitting element, and red light, each with a predetermined transmittance. The first semiconductor light-emitting element and the second semiconductor light-emitting element emit light, and white light is emitted from the red cover portion. It is characterized by the following:

[0011] According to this aspect of the present invention, a transmitted light component originating from a second semiconductor light-emitting element with a narrower wavelength range (full width at half maximum) than the phosphor is utilized, and a red cover portion is used that transmits light from the first semiconductor light-emitting element, light from the second semiconductor light-emitting element, and red light with predetermined transmittances. As a result, when the first and second semiconductor light-emitting elements emit light, white light can be emitted from the red cover portion. Furthermore, when the first and second semiconductor light-emitting elements are extinguished, a red color similar to that of a general red cover portion is emitted from the red cover portion of the present invention.

[0012] Furthermore, in the vehicle lighting device according to the present invention, Preferably, only the second semiconductor light-emitting element emits light, and amber-colored light is emitted from the red cover portion.

[0013] According to this aspect of the present invention, different colored emitted light can be obtained when both the first semiconductor light-emitting element and the second semiconductor light-emitting element are illuminated, and when only the second semiconductor light-emitting element is illuminated. In other words, different lamp functions can be provided by changing the combination of semiconductor elements that emit light.

[0014] Furthermore, in the vehicle lighting device according to the present invention, It is preferable that the chromaticity range of the red cover portion satisfies both of the following conditions 1 and 2 in the chromaticity coordinates of JIS Z8701. (Condition 1) y≦0.38 (Condition 2) y ≧ 0.94 - x

[0015] According to this aspect of the present invention, even though the transmittance of various lights is adjusted to obtain white light, when the first semiconductor light-emitting element and the second semiconductor light-emitting element are extinguished, the red cover portion exhibits the same red color as a general red cover.

[0016] Furthermore, in the vehicle lamp according to the present invention, It is preferable that the intensity of the transmitted light component irradiated from the second semiconductor light-emitting element and transmitted through the red cover portion is 4 times or less with respect to the intensity of the transmitted light component irradiated from the first semiconductor light-emitting element and transmitted through the red cover portion.

[0017] According to this aspect of the present invention, for example, white light that complies with lamp chromaticity regulations such as SAE J578C can be obtained.

[0018] Furthermore, the vehicle lamp according to the present invention In the red cover portion, The transmittance of the light from the first semiconductor light-emitting element is 5% to 40%, The transmittance of the light from the second semiconductor light-emitting element is 10% to 60%, It is preferable that the transmittance of the red light is 80% or more.

[0019] According to this aspect of the present invention, since the transmittances in the red cover portion are adjusted to satisfy the above conditions, clear white light can be obtained by the light emission of the first semiconductor light-emitting element and the second semiconductor light-emitting element.

Effects of the Invention

[0020] According to the present invention, it is possible to provide a vehicle lamp that exhibits the same red color as a general red cover portion (for example, a general outer lens colored red), and emits white light from the red cover portion when the light-emitting element emits light.

Brief Description of the Drawings

[0021] [Figure 1] A schematic diagram of a vehicle lighting device according to one embodiment of the present invention. [Figure 2] A perspective view of the light source unit of this embodiment. [Figure 3] This figure shows the transmission spectrum of the red cover portion of this embodiment. [Figure 4] A partial diagram of the chromaticity coordinates (JIS Z8701) plotting the chromaticity of the light emitted from the vehicle lamp of this embodiment. [Figure 5] A diagram illustrating the operation of the light source unit during light emission of the first semiconductor light-emitting element and the second semiconductor light-emitting element of this embodiment. [Figure 6] This figure compares the light intensity of the emitted light (transmitted light) from the first semiconductor light-emitting element and the emitted light (transmitted light) from the second semiconductor light-emitting element of this embodiment. [Figure 7] A diagram illustrating the operation of the light source unit 10 when only the second semiconductor light-emitting element of this embodiment is emitting light. [Modes for carrying out the invention]

[0022] Hereinafter, a vehicle lighting device according to one embodiment of the present invention will be described in detail with reference to the drawings. First, the vehicle lighting device 1 and light source unit 10 according to this embodiment will be described with reference to Figures 1 to 4.

[0023] Here, Figure 1 is a schematic diagram showing the general configuration of the vehicle lighting fixture 1. Figure 2 is a perspective view of the light source unit 10 provided in the vehicle lighting fixture 1. Furthermore, Figure 3 is a diagram showing the transmission spectrum of the red cover portion provided in the vehicle lighting fixture 1. Furthermore, Figure 4 is a partial diagram of the chromaticity coordinates (JIS Z8701) plotted from the chromaticity of the light emitted from the vehicle lighting fixture 1.

[0024] The vehicle lighting fixture 1 of this embodiment is, for example, a rear combination lamp mounted on the rear of an automobile. As shown in Figure 1, the vehicle lighting fixture 1 includes a lamp housing 2, a light source unit 10, a red cover portion 20 (outer lens), etc.

[0025] The light source unit 10 is housed within the lamp housing 2. The red cover portion 20 covers the front opening of the lamp housing 2 (the opening located on the rear side of the lamp housing). This defines the lamp chamber 3 that houses the light source unit 10 and the like. Furthermore, the red cover portion 20 faces the light source unit 10.

[0026] Next, as shown in Figure 2, the light source unit 10 of this embodiment includes a first semiconductor light-emitting element 11 having an emission peak wavelength of 470 nm to 520 nm, a second semiconductor light-emitting element 12 having an emission peak wavelength of 580 nm to 600 nm, a substrate 13 on which the first semiconductor light-emitting element 11 and the second semiconductor light-emitting element 12 are mounted, and the like. Furthermore, although not particularly limited, it is preferable that the light source unit 10 further includes a transparent sealing resin 14 that covers the first semiconductor light-emitting element 11 and the second semiconductor light-emitting element 12.

[0027] The first semiconductor light-emitting element 11 of this embodiment is an LED (Light Emitting Diode) having an emission peak wavelength of approximately 490 nm. More specifically, the first semiconductor light-emitting element 11 of this embodiment is composed of an InGaN-based semiconductor and emits blue-green light. However, it is not limited to semiconductors having an emission peak wavelength of 470 nm to 520 nm.

[0028] Furthermore, the second semiconductor light-emitting element 12 of this embodiment is an LED having an emission peak wavelength of approximately 590 nm. More specifically, the second semiconductor light-emitting element 12 of this embodiment is composed of an AlGaInP-based semiconductor and emits amber-colored light. However, it is not limited to this, as long as the semiconductor has an emission peak wavelength of 580 nm to 600 nm.

[0029] In this embodiment, the first semiconductor light-emitting element 11 and the second semiconductor light-emitting element 12 are LEDs, but they may also be other semiconductor light-emitting elements (for example, laser diodes, etc.) having the aforementioned emission peak wavelengths, or other types of semiconductor light-emitting elements.

[0030] Next, the red cover portion 20 is composed of a transparent resin plate colored with a red pigment. Here, the red pigment of the red cover portion 20 is not particularly limited. Examples of red pigments include azo compounds, cyanine compounds, perylene compounds, and dioxazine compounds. Furthermore, the material of the transparent resin plate colored with the red pigment is not particularly limited. Examples of transparent resin plates include acrylic resin and polycarbonate resin.

[0031] Furthermore, an example of the transmission characteristics of the red cover portion 20 is one that corresponds to the transmission spectrum shown in Figure 3. More specifically, an example of the transmission characteristics of the red cover portion 20 is one that satisfies all of the following conditions (3) to (5).

[0032] (Condition 3): For example, the transmittance of blue light to greenish-blue light (blue-green light) with wavelengths of 400nm to 550nm is 5% to 40%. (Condition 4): For example, the transmittance of amber-colored light with a wavelength of 580nm to 600nm is 10% to 60%. (Condition 5): For example, the transmittance of red light with a wavelength of 620nm to 730nm is 80% or higher.

[0033] In other words, the red cover portion 20 transmits the red component of ambient light with a transmittance as described in condition 5, and transmits the light emitted from the first semiconductor light-emitting element 11 and the light emitted from the second semiconductor light-emitting element 12 with a transmittance as described in conditions 3 and 4.

[0034] As a result, when the first semiconductor light-emitting element 11 and the second semiconductor light-emitting element 12 emit light, white light corresponding to the chromaticity range within or near frame 40 (white light as defined by the US Lamp Chromaticity Act SAE J578C) in the chromaticity coordinates of Figure 4 is emitted from the red cover portion 20.

[0035] However, when the first semiconductor light-emitting element 11 and the second semiconductor light-emitting element 12 emit light, if, for example, white light with a chromaticity range satisfying 0.500≧x≧0.310, y≦0.150+0.640x, y≧0.050+0.750x, and 0.440≧y≧0.382 in chromaticity coordinates based on JIS Z8701 is emitted from the red cover portion 20, then the transmission characteristics of the red cover portion 20 are not limited to the above.

[0036] Furthermore, it is preferable that the red cover portion 20 of this embodiment has a chromaticity range that satisfies both of the following conditions 1 and 2 in the chromaticity coordinates of JIS Z8701. (Condition 1) y≦0.38 (Condition 2) y≧0.94-x

[0037] With respect to the chromaticity range of the red cover portion 20, by satisfying the above conditions 1 and 2 (the region enclosed by line segment 41 in Figure 4), when the first semiconductor light-emitting element 11 and the second semiconductor light-emitting element 12 are extinguished, the entire red cover portion will exhibit the same red color as a general red cover.

[0038] According to this embodiment, the transmitted light component originating from the second semiconductor light-emitting element 12, which has a narrower wavelength range (full width at half maximum) than the phosphor, is utilized, and a red cover portion 20 is used that transmits light from the first semiconductor light-emitting element 11, light from the second semiconductor light-emitting element 12, and red light with predetermined transmittances. As a result, when both light-emitting elements emit light, white light is emitted from the red cover portion 20.

[0039] Next, the operation of the vehicle lighting device 1 according to this embodiment will be explained with reference to Figures 5 to 7. Here, Figure 5 is a diagram illustrating the operation of the light source unit 10 when the first semiconductor light-emitting element 11 and the second semiconductor light-emitting element 12 are emitting light. Figure 6 is a diagram comparing the light intensity of the emitted light (transmitted light) from the first semiconductor light-emitting element 11 and the emitted light (transmitted light) from the second semiconductor light-emitting element 12. Furthermore, Figure 7 is a diagram illustrating the operation of the light source unit 10 when only the second semiconductor light-emitting element 12 is emitting light.

[0040] As shown in Figure 5(a), when the first semiconductor light-emitting element 11 and the second semiconductor light-emitting element 12 are illuminated, the light irradiated from both is directed toward the red cover portion 20. As described above, the red cover portion 20 transmits the light irradiated from the first semiconductor light-emitting element 11 with a transmittance of 5% to 40%, and transmits the light irradiated from the second semiconductor light-emitting element 12 with a transmittance of 10% to 60%. In addition, red light originating from ambient light, for example, is transmitted through the red cover portion 20.

[0041] As a result, the transmitted light component originating from the first semiconductor light-emitting element 11, the transmitted light component originating from the second semiconductor light-emitting element 12, and the red transmitted light component originating from ambient light are emitted to the outside of the red cover portion 20. Consequently, white light, which is a mixture of these transmitted light components, is emitted to the outside of the red cover portion 20. In this embodiment, the white light emitted from the red cover portion 20 is used as a backlight (Figure 5(b)). Note that reference numeral 21 in Figure 5(b) corresponds to the white light emission region in the red cover portion 20.

[0042] Here, the light intensity I of the transmitted light (emitted light) component originating from the second semiconductor light-emitting element 12 that has passed through the red cover portion 20 is A This is the light intensity I of the transmitted light (emitted light) component originating from the first semiconductor light-emitting element 11. B It is preferable that the ratio is four times or less.

[0043] When the light intensities of both meet the above conditions, white light satisfying SAE J578C can be obtained, as shown in Figure 4 (the chromaticity of the light emitted from the red cover portion 20 can be placed within the frame 40 in the chromaticity coordinates of Figure 4).

[0044] Next, as shown in Figure 7(a), when only the second semiconductor light-emitting element 12 emits light, due to the transmission characteristics of the red cover portion 20, amber light similar to the illumination light from the second semiconductor light-emitting element 12 is emitted from the red cover portion 20. In this embodiment, the amber light emitted from the red cover portion 20 is used as a turn signal lamp. Note that reference numeral 22 in Figure 7(b) corresponds to the amber light emission region in the red cover portion 20.

[0045] Thus, different colored light can be obtained depending on whether both the first semiconductor light-emitting element 11 and the second semiconductor light-emitting element 12 are emitting light or only the second semiconductor light-emitting element 12 is emitting light. In other words, different lamp functions can be provided by changing the combination of semiconductor elements that emit light.

[0046] Embodiments of the present invention have been described in detail above. However, the foregoing description is intended to facilitate understanding of the present invention and is not intended to limit it. The present invention may include modifications and improvements that can be made without departing from its spirit. Furthermore, the present invention includes equivalents thereof.

[0047] For example, the vehicle light fixture 1 may include an inner lens interposed between the first semiconductor light-emitting element 11 and the second semiconductor light-emitting element 12 and the red cover portion 20. The vehicle light fixture 1 may also include a reflector that distributes the light emitted from the first semiconductor light-emitting element 11 and the second semiconductor light-emitting element 12 towards the red cover portion 20.

[0048] Furthermore, although the aforementioned vehicle lighting fixture 1 is a rear combination lamp, it may be of other types (for example, a vehicle lid lamp, etc.). [Explanation of symbols]

[0049] 1… Vehicle lighting equipment 10… Light source unit 11… First semiconductor light-emitting element 12… Second semiconductor light-emitting element 20… Red cover section 21… White light emission area 22… Amber-colored light emission area

Claims

1. A first semiconductor light emitting element having an emission peak wavelength in the range of 470 nm to 520 nm; A second semiconductor light emitting element having an emission peak wavelength in the range of 580 nm to 600 nm; a red cover portion facing the first semiconductor light emitting element and the second semiconductor light emitting element; Equipped with the red cover portion transmits light from the first semiconductor light emitting element, light from the second semiconductor light emitting element, and red light at a predetermined transmittance, the first semiconductor light emitting element and the second semiconductor light emitting element emit light, and white light is emitted from the red cover portion; Only the second semiconductor light emitting element emits light, and amber light is emitted from the red cover portion. A vehicle lamp characterized by the above.

2. The chromaticity range of the red cover portion satisfies both of the following conditions 1 and 2 in the chromaticity coordinates of JIS Z8701:

2. A vehicle lamp according to claim 1. (Condition 1) y≦0.38 (Condition 2) y≧0.94−x

3. The intensity of a transmitted light component irradiated from the second semiconductor light emitting element and transmitted through the red cover portion is four times or less than the intensity of a transmitted light component irradiated from the first semiconductor light emitting element and transmitted through the red cover portion.

3. A vehicle lamp according to claim 1 or 2.

4. In the red cover portion, the transmittance of light from the first semiconductor light emitting element is 5% to 40%, the transmittance of light from the second semiconductor light emitting element is 10% to 60%, The transmittance of the red light is 80% or more. The vehicular lamp according to any one of claims 1 to 3.

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