JPH06187810A - Vehicle light with led as light source - Google Patents

Abstract

PURPOSE:To reduce the total number of LEDs so as to reduce costs and to restrain temperature rise by disposing a lens to cover at least other than the front part of the line of LEDs, the lens provided with rectilinear, polyhedral prism cuts extending in parallel to the line of LEDs. CONSTITUTION:Rectangular, polyhedral prism cuts 5 are provided on the surface of the lens 4 of a vehicle light 1 and so rays of light from LEDs 2 are given set angles beta1 to beta4 of depth and the ray of light from that LEDs 2 which is located to coincide with one of diffraction angles is directed in the forward direction and the rays of light which deviate from that direction appear as beams aligned in the direction perpendicular to the line of light sources. Then the lens 4 is disposed to cover at least other than the front part of the line of LEDs 2 so that LEDs appear to be disposed also in the direction perpendicular to the line of LEDs 2 because of the cuts 5. As a result, the total number of LEDs can be reduced and then costs can be reduced and temperature rise restrained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular lamp, and more particularly to a vehicular lamp having an LED (light emitting diode) as a light source.

[0002]

2. Description of the Related Art Conventionally, when a vehicle lamp is formed by using an LED 80, which has been generally packaged in a bell shape called a dome shape, as a light source, the vehicle lamp is an auxiliary braking lamp 90. When a large light emitting area is not required, as shown in FIG. 10, the LEDs 80 are arranged in a row with a relatively dense pitch to form a line light source 81.
The front surface is covered with an appropriate lens 91.

At this time, as a reference for setting the pitch P when the LEDs 80 are arranged in a row and used as the linear light source 81, in order to reduce the uneven brightness on the surface of the lens 91, FIG.
As shown in FIG. 7, the main irradiation angle α (angle at which the luminance is halved with respect to the maximum value) of the LED 80 is set to be overlapped by the lens 91, but in the packaging described above, the main irradiation angle α is set. Since the angle α is as narrow as about 20 °, the pitch P is inevitably narrow.

[0004]

However, the same L
When, for example, a taillight / braking light that requires a large light emitting area using the ED 80 as a light source is to be formed, the LEDs must be arranged in rows and columns at the narrow pitch P described above, and the number of LEDs 80 is enormous. As a result, the cost of the vehicular lamp increases, and the amount of heat generated during lighting also increases, causing a decrease in brightness in a portion where the temperature rises significantly, such as the central part, and uneven brightness. Problems such as breakage have also occurred in terms of reliability, and the solution of these points has become an issue.

[0005]

The present invention provides a plurality of LEs as a concrete means for solving the above-mentioned conventional problems.
In a vehicular lamp using as a light source an LED in which Ds are arranged in at least one row, a polyhedral prism formed by combining a plurality of different refraction angles in a cross section orthogonal to the row of LEDs is parallel along the row direction. A vehicle lamp using an LED as a light source, characterized in that a lens provided with a continuous linear polygonal prism cut is formed, and the lens is arranged so as to cover at least a portion other than a front portion of the row of LEDs. By providing the above, it is possible to significantly reduce the number of LEDs used and solve the above-mentioned conventional problems.

[0006]

EXAMPLES The present invention will now be described in detail based on the examples shown in the drawings. 1 shows the first embodiment of the present invention, and the reference numeral 1 in the figure is a vehicle lamp.
The vehicle lamp 1 has the LED 2 as described in the conventional example.
Is similar to the point that the linear light sources 3 arranged in a row at a relatively narrow pitch are used as the light source.
The point that the lens 4 is provided in front of the irradiation direction is also the same.

At this time, the lens cut provided on the surface of the lens 4 is made by a plurality of prisms having different refraction angles in a cross section orthogonal to the linear light source 3 as shown in an enlarged view in FIG. 2 according to the present invention. It is formed as a combined polygonal prism, and this shape is translated in the column direction of the linear light source 3 to form a linear polygonal prism cut 5.
It is said that. It should be noted that the number of prism stages combined with the linear multi-sided prism cut 5 can be freely set, and the minimum is 1 as shown as the linear multi-sided prism cut 15 in FIG.
It may be stepped.

Next, the operation of the vehicular lamp 1 of the present invention having the above-mentioned structure will be described. In order to simplify the description, in the first embodiment, the linear light source 3 will be described as a single line. To do. 4 schematically shows a cross section orthogonal to the linear light source 3 of the vehicular lamp 1. The linear polygonal prism cut 5 is shown in a shape omitted, but it is assumed that the operation is performed correctly. Explain and line light source 3
Also, the description will be made by using one LED 2 as a representative.

First, considering the state of the vehicular lamp 1 viewed from the front side in FIG. 4, among the plurality of linear polygonal prism cuts 5 provided on the surface of the lens 4, the linear polygonal prism is shown. One of a plurality of refraction angles set for cut 5, and linear polyhedral prism cut 5 and L
The linear polygonal prism cut 5 at a position where the projected angles β1 to β4 formed by the ED2 coincide with each other serves to direct the light from the LED 2 in the viewing direction, that is, the front direction, and the adjacent one is the front direction. The light is refracted in a direction slightly deviated from the above, and the linear polyhedral prism cut 5 following this is gradually increased in the amount deviated from the front direction.

FIG. 5 shows the above state as a pattern appearing on the surface of the lens 4, and on the surface of the lens 4, along the direction Y orthogonal to the column direction X in which the linear light sources 3 are arranged. The aligned light beams H appear, and the LEDs 2 are also viewed in the orthogonal direction Y as described above. Therefore, even if the lens 4 is widened in the orthogonal direction Y, the entire surface should emit light. Is possible. still,
The number of the light beams H is increased by increasing the number of prism surfaces of the linear polygonal prism cuts 5, and the interval is narrowed by making the linear polygonal prism cuts 5 fine.

If the above-mentioned action is shown by a specific numerical value, in the vehicle lamp using the linear light source 3, for example, the orthogonal direction Y in the lens in which the conventional lens cut such as the fish-eye cut is performed.
While the limit of the width of light emitted from the entire surface is about 15 to 20 mm, the lens 4 provided with the polyhedral prism cut 5 of the present invention emits light in a range of about 50 mm, which is about 2 to 3 times. It becomes possible.

FIG. 6 shows a second embodiment of the present invention, which is different from the first embodiment in which the linear polygonal prism cut 5 is provided on the entire surface of the lens 4. However, the linear polyhedral prism cut 5 is not provided in front of the LED 2 (line light source 3) of the lens 14, and instead of this, a diffusion degree such as a fisheye lens cut or a cylindrical lens cut similar to the conventional example is provided. The lens cut 6 that can control the above is provided, and this portion serves as the brightness generating portion 14a in the lens 14.

By doing so, the light of the highest brightness portion emitted from the LED 2 is irradiated to the front without being diffused by the linear polygonal prism cut 5, and the brightness of the vehicle lamp 1 is increased. When the vehicle lighting device 1 is used as a lighting device such as a brake light that is required to have a relatively high luminance, the performance required by the luminance generation unit 14a is satisfied.

When providing the brightness generating section 14a, for example, as shown in the drawing, an auxiliary condenser lens cut 7 is provided between the LED 2 and the lens 14 so that the brightness generating section 14a converges. It is possible to further improve the brightness. Since the vehicular lamp 1 can be used as a brake light in the configuration of the second embodiment, it can be used as a tail light having a lower brightness than that by limiting the current applied to the LED 2. To do.

As a third embodiment, as shown in FIG. 7, the auxiliary condenser lens cut 17 may be transferred to the back surface of the lens 24 as a Fresnel cut. In this case, the lens cut 16 is the surface of the lens 24. Be moved to the side.
In the third embodiment as well, the lens cut 16 and the auxiliary condenser lens cut 17 constitute the luminance generating section 24a, and the same operation and effect as the second embodiment can be obtained. Becomes

Next, FIG. 8 shows a fourth embodiment of the present invention. In all the previous embodiments, the line light source 3 is described as a single line, but in the third embodiment, the line light source 3 is used. In a plurality of rows. At this time, the lens 34 may have a linear polyhedral prism cut 5 on the entire surface as described in the first embodiment, or may be described in the second embodiment. Any of those provided with a brightness generating section as shown in the figure (the figure shows an example in which the brightness generating section 34a is provided).
But good.

Also in the case of this embodiment, the pattern appearing on the surface of the lens 34 is as shown in FIG.
Is arranged in the middle position, the line direction X of the linear light source 3 is
This is exactly the same as in each of the previous embodiments, in which the light beams H that are aligned along the orthogonal direction Y appear, and the entire surface of the lens 34 shines.

[0018]

As described above, according to the present invention, L
A lens provided with a linear polyhedral prism cut in which a polyhedral prism formed by combining a plurality of different refraction angles in a cross section orthogonal to the row of EDs is continuous in parallel along the row direction is formed, and the lens is formed by at least the LED Since the vehicular lamp having the LED as the light source is arranged so as to cover a portion other than the front part of the row of the column, when the vehicular lamp having a wide lens area is used as the light source, Due to the narrow angle α, a large number of LEDs must be arranged in close contact with each other in the vertical and horizontal directions, which causes problems such as cost increase or performance deterioration. This allows the LEDs to be viewed as if they are arranged even in the direction orthogonal to the row of LEDs, thus reducing the total number of LEDs to be arranged. With exhibits extremely excellent effect down, in which excellent effects in improving the reliability by reducing temperature rise of the vehicular lamp.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of a vehicular lamp using an LED as a light source according to the present invention.

FIG. 2 is also an enlarged perspective view showing a portion of a linear polygonal prism cut of the vehicular lamp according to the present invention.

FIG. 3 is a perspective view showing another embodiment of the same linear polygonal prism cut.

FIG. 4 is an explanatory view showing the operation of the same first embodiment.

FIG. 5 is an explanatory diagram showing a light emitting state on a lens surface of the same first embodiment.

FIG. 6 is a sectional view showing a second embodiment of the present invention.

FIG. 7 is a sectional view showing a third embodiment of the present invention.

FIG. 8 is a sectional view showing a fourth embodiment of the present invention.

FIG. 9 is an explanatory diagram showing a light emitting state on the lens surface of the same fourth example.

FIG. 10 is a perspective view showing a conventional example.

11 is a cross-sectional view taken along the line AA of FIG.

[Explanation of symbols]

 1 ... Vehicle lamp 2 ... LED 3 ... Linear light source 4,14,24,34 ... Lens 14a, 24a, 34a ... Luminance generator 5,15 ... Linear polyhedral prism cut 6 ... Lens cut 7, 17 ... Auxiliary condenser lens cut

Claims (2)

[Claims] 1. A vehicular lamp having an LED as a light source, the LED comprising a plurality of LEDs arranged in at least one row.
A lens provided with a linear polyhedral prism cut in which a polyhedral prism formed by combining a plurality of different refraction angles in a cross section orthogonal to the row of the LEDs is continued in parallel along the row direction is formed, and at least the lens is formed. A vehicle lamp using an LED as a light source, which is arranged so as to cover a portion other than a front portion of an LED row. 2. The brightness generating portion is characterized in that a fisheye lens or a cylindrical lens parallel to the row is provided in place of the polyhedral prism cut in a front portion of the LED row of the lens. The LE according to claim 1,
A vehicle lamp having D as a light source.