JP2006331650A - Vehicle lighting - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicular lamp capable of reliably removing snow attached to a front lens at a low cost with a simple configuration.
SOLUTION: A light source 11 that emits visible light that does not include infrared light and has an optical axis that extends substantially horizontally forward, a concave reflecting surface 12 that reflects the visible light from the light source forward, A front lens made of a light-transmitting material so as to cover an emission surface of visible light that is disposed in front of the light source and travels forward from the light source or the reflection surface; The vehicular lamp 10 is configured so that 13 is made of a translucent material containing a rare earth element that absorbs visible light and generates infrared light or an ion 13a thereof.
[Selection] Figure 1

Description

  The present invention relates to a vehicular lamp that is used, for example, as a headlamp, an auxiliary headlamp, or the like provided at the front of an automobile, and particularly uses a light source that emits light that does not contain infrared light, such as an inorganic LED. The present invention relates to a vehicular lamp.

  Conventionally, such a vehicular lamp is configured as shown in FIG. 3, for example. That is, in FIG. 3, the vehicular lamp 1 is, for example, an automobile headlamp, and is disposed in front of the light source 2, the reflective surface 3 that reflects light from the light source 2 forward, and the reflective surface 3. The front lens 4 is made up of.

The light source 2 is composed of at least one inorganic LED, and by feeding power to each inorganic LED, each inorganic LED is driven to emit light.
The reflection surface 3 is formed, for example, as a concave parabolic reflection surface toward the front so as to reflect the light emitted from the light source 2 toward the rear or the side toward the front.

The front lens 4 is made of a translucent material, and transmits light from the light source 2 or the reflecting surface 3 forward and protects the light source 2 and the reflecting surface 3.
Here, as the translucent material, for example, glass or a plastic material such as polycarbonate is used.

  According to the vehicular lamp 1 having such a configuration, the light emitted from the light source 2 is reflected directly or reflected by the reflecting surface 3 and irradiated forward through the front lens 4, for example, a so-called passing beam. The range of the light distribution pattern is illuminated.

  In such a vehicular lamp 1, although it is used as the light source 2, it is comprised from inorganic LED. Such an inorganic LED is known to emit light that does not contain infrared light, and the front lens 4 is not heated by light from the light source 2.

By the way, in the case of a vehicular lamp using a halogen light bulb or a so-called HID as a light source, light including infrared light is emitted from the light source, so that the front lens is heated by the light from the light source and the temperature of the front lens is increased. Is relatively high.
Accordingly, when snow adheres to the outer surface of the front lens, for example, during snowfall, it melts due to the heat of the front lens, and snow does not accumulate on the front lens.

By the way, in the vehicle lamp 1 described above, since the inorganic LED is used as the light source 2, the front lens 4 is not heated by the light from the light source 2. Low.
Therefore, for example, when snow falls on the outer surface of the front lens 4 during snowfall or the like, the snow is not melted by the heat of the front lens 4 and the snow is accumulated on the outer surface of the front lens 4. For this reason, the light radiated forward from the light source 2 or the reflecting surface 3 is blocked by snow accumulated on the outer surface of the front lens 4, and sufficient illuminance cannot be obtained with respect to the front field of view. End up.

  Further, for example, a vehicular lamp having a wiper for removing snow accumulated on the outer surface of the front lens is also known. However, the mechanical configuration of the vehicular lamp is complicated, and the vehicular lamp that is lit is turned on. In addition, depending on the temperature and the state of snowfall, the snow attached to the outer surface of the front lens cannot be removed sufficiently and the illuminance decreases.

On the other hand, Patent Document 1 discloses a vehicle lamp having a carbon-based heating element therein.
According to this configuration, the carbon-based heating element generates heat by feeding and heats the front lens. Therefore, since the temperature of the front lens becomes relatively high, if snow adheres to the outer surface of the front lens, for example during snowfall, it will melt due to the heat of the front lens, and snow will accumulate on the front lens. Absent.

Patent Document 2 discloses a vehicle headlamp including an infrared semiconductor light emitting element adjacent to a light source.
According to this vehicular headlamp, infrared light is irradiated forward by a semiconductor light emitting element for infrared light, and so-called night vision is performed by an infrared camera, so that the front of the vehicle is surely secured at night, for example. It can be observed.
JP 2004-127574 A JP 2004-241138 A

By the way, in the vehicular lamp according to Patent Document 1, the front lens can be heated by the carbon-based heating element provided therein, and snow or the like adhering to the outer surface of the front lens can be melted. In addition to providing a heating element, it is necessary to provide a power supply line for the carbon-based heating element, which complicates the structure.
Further, in the vehicle headlamp according to Patent Document 2, the infrared light for night vision is irradiated forward by the semiconductor light emitting element for infrared light for generating infrared light for night vision. However, this semiconductor light emitting element for infrared light is not for heating the front lens, and it is also possible to heat the front lens. In addition, it is necessary to provide a power supply line for the semiconductor light emitting element for infrared light, which complicates the structure.

  In view of the above, an object of the present invention is to provide a vehicular lamp that can reliably remove snow attached to a front lens at a low cost with a simple configuration.

  According to the configuration of the present invention, the object is to emit visible light that does not contain infrared light and to have a light source, preferably an inorganic LED, having an optical axis extending substantially horizontally forward, and visible light from the light source forward. A concave reflecting surface that reflects toward the light source, and a front lens that is disposed in front of the light source and is made of a translucent material so as to cover a light emitting surface that travels forward from the light source or the reflecting surface. In the vehicular lamp, the front lens absorbs visible light and generates infrared light, preferably a rare earth element, preferably Nd, Er, Yb, Sm, Tb, Eu, Cr, La or ions thereof. It is achieved by a vehicular lamp characterized in that it is made of a translucent material containing.

  In the vehicular lamp according to the present invention, preferably, the translucent material constituting the front lens generates energy transfer with respect to visible light from the light source to generate infrared light by a rare earth element or ions thereof. It contains a metal that converts light of a wavelength that can be generated, preferably any one of Eu, Tb, Sm, Yb, or ions thereof.

According to the above configuration, visible light that does not include infrared light emitted from a light source is reflected directly or by a reflecting surface and irradiated forward through a front lens, for example, a light distribution pattern of a passing beam. Illuminate the range.
At that time, when a part of the light directly emitted from the light source and the light reflected by the reflecting surface is incident on the rare earth element or its ion contained in the translucent material constituting the front lens, these rare earth elements Alternatively, the ions absorb incident light and generate infrared light.

Accordingly, infrared light generated from these rare earth elements or ions thereof is incident on the front lens to heat the front lens, so that the temperature of the front lens becomes relatively high.
As a result, even if snow is attached to the outer surface of the front lens, for example, during snowfall, the attached snow will be melted by the heat of the front lens, and snow will not accumulate on the outer surface of the front lens. The light with sufficient illuminance is irradiated forward and the field of view can be secured.

The translucent material constituting the front lens is a metal that generates energy transfer with respect to visible light from a light source, and converts it into light having a wavelength capable of generating infrared light by a rare earth element or ions thereof, preferably Any of Eu, Tb, Sm, and Yb is preferable. Or if the ion contains the light emission wavelength of visible light from the light source is shifted with respect to the wavelength of light that the rare earth element or the ion absorbs to generate infrared light, When there is little or almost no light, the above-mentioned metal is mixed, so that the visible light from the light source is transferred by the metal, and the visible light having the optimum wavelength for the visible light absorption of the rare earth element or its ions. Convert to
Thereby, the visible light from the light source is changed in energy by the metal and is absorbed by the rare earth element or its ions to generate infrared light. Accordingly, the front lens is heated by the infrared light, and the temperature of the front lens becomes relatively high.

As described above, according to the vehicular lamp according to the present invention, even when a light source that emits visible light that does not include infrared light is used, a rare earth element is used for the translucent material constituting the front lens. By mixing elements or ions thereof, when visible light from the light source is incident on the front lens, a part of the visible light is absorbed by the rare earth elements or ions thereof and infrared light is generated. It will be.
Accordingly, the outer surface of the front lens can be used in the event of snowfall, etc. by generating infrared light and heating the front lens with a simple configuration without providing a heating element or an infrared light emitting element inside as in the prior art. It is possible to melt and eliminate the snow adhering to the snow. As a result, snow does not accumulate on the outer surface of the front lens, and light with sufficient illuminance is irradiated forward, thereby ensuring visibility.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS.
The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. As long as there is no description of the effect, it is not restricted to these aspects. [Example 1]

  FIG. 1 shows a configuration of a first embodiment of a vehicular lamp to which the present invention is applied. In FIG. 1, a vehicular lamp 10 is an automobile headlamp, and includes a light source 11, a reflective surface 12 that reflects light from the light source 11 forward, and a front surface disposed in front of the reflective surface 12. And a lens 13.

  The light source 11 is a light source used as an automobile headlight or an auxiliary headlamp, and is a light source such as an inorganic LED that emits visible light that does not include infrared light. In addition, power is supplied.

  The reflection surface 12 is formed as a concave parabolic reflection surface, for example, forward so as to reflect light emitted from the light source 11 rearward or sideward toward the front.

  The front lens 13 is made of a translucent material, for example, plastic such as glass or polycarbonate, and transmits the light from the light source 11 or the reflecting surface 12 forward and the entire light emitting surface of the vehicular lamp 10. Is disposed so as to protect the light source 11 and the reflecting surface 12.

The translucent material constituting the front lens 13 contains rare earth elements or ions thereof, for example, Nd or Nd ions 13a.
In addition, this translucent material may preferably contain zinc oxide, aluminum oxide or the like in order to obtain surface gloss and gloss.

The translucent material contains Nd or Nd ions, so that it absorbs visible light from the light source 11 and generates infrared light.
and Visible room temperature fluuenceence induced by continuous laser excitation of new Nd3 +: phosphate glasses (Journal of NON-CRYSTALLINES ID
259 (1999) 23-30).
At that time, it is known that the emission spectrum of infrared rays generated varies depending on the content of Nd ions, but the content can be set to a level that does not impair the strength of the base material such as glass and polycarbonate. .

Here, a specific method for manufacturing the front lens 13 will be described.
First, the Nd compound according to the above document is mixed with a raw material of polycarbonate resin at a predetermined ratio to produce a pellet having a size of about 5 mmφ × 8 mm, for example.
Subsequently, the above-described pellets are charged from a raw material charging port of a normal injection molding machine. Finally, the front lens 13 is molded by an injection molding machine.
In this way, the front lens 13 is manufactured.

  The vehicular lamp 10 according to the embodiment of the present invention is configured as described above. When power is supplied to the light source 11, visible light that does not include infrared light is emitted from the light source 11 and directly or on the reflection surface 12. The light is reflected and irradiated forward through the front lens 13 to illuminate a range of a so-called passing beam light distribution pattern, for example.

At that time, when the light directly emitted from the light source 11 and the light reflected by the reflecting surface 12 pass through the front lens 13, a part of the light enters the Nd or Nd ions 13 a included in the front lens 13. , Nd or Nd ions 13a absorb incident light and generate infrared light.
The front lens 13 is heated by the infrared light entering the front lens 13. Thereby, the temperature of the front lens 13 becomes relatively high.

  Therefore, for example, when snow is attached to the outer surface of the front lens 13 during snowfall, the attached snow is melted by the heat of the front lens 13. As a result, snow does not accumulate on the outer surface of the front lens 13, and light with sufficient illuminance is irradiated forward, and the field of view can be secured.

  In this case, since it is a simple configuration in which Nd or Nd ions 13a are mixed into the translucent material constituting the front lens 13, a complicated mechanical configuration is unnecessary, and it can be easily manufactured at low cost. It will be.

Thus, according to the vehicular lamp 10 according to the embodiment of the present invention, even when the light source 11 that emits visible light not including infrared rays is used, the translucent material constituting the front lens 13 is used as the translucent material. By mixing the rare earth element or its ions, when visible light from the light source 11 enters the front lens 13, a part of the visible light is absorbed by the rare earth element or its ions described above, and infrared light is emitted. Will occur. Therefore, since the front lens 13 can be heated by generating infrared light with a simple configuration, even if snow adheres to the front lens 13 during, for example, snowfall, the relatively high temperature of the front lens 13 is increased. The snow melts due to heat, and the snow accumulates on the outer surface of the front lens 13, so that a good field of view can be ensured without disturbing the light irradiated toward the front.
[Example 2]

FIG. 2 shows a configuration of a second embodiment of a vehicular lamp to which the present invention is applied. 2, the vehicular lamp 20 has substantially the same configuration as that of the vehicular lamp 10 shown in FIG. 1, and the same components are denoted by the same reference numerals and description thereof is omitted.
The vehicular lamp 20 differs from the vehicular lamp 10 shown in FIG. 1 only in that the translucent material constituting the front lens 13 further contains a metal or ions 13b thereof. .

Here, the metal or its ions 13b transfer visible light from the light source 11 to energy, and the Nd or Nd ions 13a generate infrared light and convert it into visible light in an optimum wavelength range for absorption. It is configured as such.
The metal or its ion 13b is, for example, Eu, Tb, Sm, Yb or its ion.

  Thereby, the emission wavelength of visible light from the light source 11 is slightly or completely deviated from the optimum wavelength range for the Nd or Nd ion 13a to generate and absorb infrared light, and the Nd or Nd ion When the amount of infrared light generated by absorbing light visible from the light source 11 is slight or zero, the visible light from the light source 11 is moved by the metal or its ions 13b to transfer energy. The Nd or Nd ion 13a can generate infrared light and convert it into light having an optimum wavelength range for absorption.

Such energy transfer is described in, for example, the document “Cr3 + → Nd3 + energy”.
“Transfer in fluorophosphate glass inverted by time-resolved laser spectroscopy (PHYSICAL REVIEW VOLUME 48, NUMBER 5 (published on August 1, 1993) 2941-2947)”.

  Further, the spectral characteristics of Eu, Tb, Sm, and Yb, which are metals that cause energy transfer, are described in the document “Glass ceramic-a new laser host material (J. Appl. Phys., Vol. 44, No. 5, 1973). Yearly) ”.

  According to the vehicular lamp 20 having such a configuration, by supplying power to the light source 11, visible light that does not include infrared light is emitted from the light source 11 and reflected directly or by the reflecting surface 12, and the front lens 13. For example, so as to illuminate a range of a so-called passing beam light distribution pattern.

At that time, when the light directly emitted from the light source 11 and the light reflected by the reflecting surface 12 pass through the front lens 13, a part of the light enters the metal or metal ion 13b, and the metal or metal ion 13b. Absorbs incident light and generates visible light.
This visible light is visible light in an optimum wavelength region for the Nd or Nd ion 13a to generate and absorb infrared light.

Then, this visible light is incident on Nd or Nd ions 13a included in the front lens 13, and the Nd or Nd ions 13a absorb the incident light and generate infrared light.
Therefore, the front lens 13 is heated when the infrared light is incident on the front lens 13. Thereby, the temperature of the front lens 13 becomes relatively high.

  Therefore, for example, when snow is attached to the outer surface of the front lens 13 during snowfall, the attached snow is melted by the heat of the front lens 13. As a result, snow does not accumulate on the outer surface of the front lens 13, and light with sufficient illuminance is irradiated forward, and the field of view can be secured.

  In this case, since it is a simple configuration in which the Nd or Nd ions 13a and the metal or ions 13b thereof are mixed into the translucent material constituting the front lens 13, a complicated mechanical configuration is unnecessary and the cost is low. Can be easily manufactured.

In the above-described embodiment, the case where the translucent material constituting the front lens 13 includes Nd or Nd ions as rare earth elements or ions thereof is not limited to this, but other rare earth elements, Obviously, for example, Er, Yb, Sm, Tb, Eu, Cr, La, or ions thereof may be included.
In the above-described embodiment, the vehicular lamps 10 and 20 are configured as automobile headlamps. However, the present invention is not limited to this. For example, an auxiliary headlamp such as a fog lamp of an automobile or a front of a motorcycle is used. The present invention can also be applied to a vehicular lamp such as an illumination lamp.

  In this way, according to the present invention, it is possible to provide an extremely excellent vehicular lamp that can reliably remove snow attached to the front lens at a low cost with a simple configuration.

1 is a schematic side view showing the configuration of a first embodiment of a vehicular lamp to which the present invention is applied. It is a schematic side view which shows the structure of 2nd embodiment of the vehicle lamp to which this invention is applied. It is a schematic side view which shows the structure of an example of the conventional vehicle lamp.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Vehicle lamp 11 Light source 12 Reflecting surface 13 Front lens 13a Nd or its ion 13b Metal or its ion

Claims (5)

A light source that emits visible light that does not contain infrared light and has an optical axis that extends substantially horizontally forward;
A concave reflecting surface that reflects the visible light from the light source forward,
A vehicular lamp including a front lens made of a translucent material so as to cover an emission surface of visible light that is disposed in front of the light source and travels forward from the light source or the reflection surface;
A vehicular lamp characterized in that the front lens is made of a translucent material containing rare earth elements or ions thereof that absorb visible light and generate infrared light.   The vehicular lamp according to claim 1, wherein the light source is composed of an inorganic LED.   3. The vehicular lamp according to claim 1, wherein the rare earth element is any one of Nd, Er, Yb, Sm, Tb, Eu, Cr, and La.   A translucent material constituting the front lens further generates energy transfer with respect to visible light from a light source, and converts the light into a wavelength that can generate infrared light by the rare earth element or ions thereof, or The vehicular lamp according to any one of claims 1 to 3, characterized in that the ion is included.   5. The vehicular lamp according to claim 4, wherein the metal is any one of Eu, Tb, Sm, and Yb.

Images