JP2543306Y2 - Direct optics for vehicle headlamps - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a direct-light-type optical system structure that forms one vehicle lamp or forms a part of one vehicle lamp. .

[Conventional technology]

FIG. 4 shows a conventional headlight widely used,
FIG. 3B is a horizontal sectional view.

A light source bulb (not shown) is installed near the focal point F of the rotating parabolic mirror 1.

The light emitted from the light source bulb is reflected by the rotating parabolic mirror 1 and becomes a parallel light flux in the optical axis Z direction and enters the prism lens 2.

Parallel beam incident on the prism lens 2 is spread by angle theta _m to the left and right by the prism lens 2.

Light distribution pattern headlight conventional example of this type, over a range of angular theta _m to the left and right as shown in FIG. 4 (A), a relatively uniform light distribution.

However, if desired, do not use the prism lens 2,
It is expected to develop an optical system that can obtain a desired light distribution pattern even using a transparent lens or a simple prism lens that is close to a transparent lens.

 FIG. 5 shows a known example different from the above.

As shown in FIG. 1B, the diffuse reflector 3 of this known example receives light emitted from the point F, reflects light substantially parallel to the optical axis Z at the center of the reflector, and To the optical axis Z as it moves to (expands forward)
It reflects light in a direction, in the left and right end portions reflected in the opening direction by the angle theta _m.

In the light distribution pattern of this type of headlamp, as shown in FIG. 1A, the amount of irradiation light is too small at both left and right ends.

In addition, the auxiliary spherical mirror 4 cannot be provided at the position indicated by the broken line, or a condenser lens cannot be provided at this position to effectively use the direct light.

The configuration shown in FIG. 6 is known as an example in which the disadvantages of the known example shown in FIG. 5 are eliminated, the auxiliary spherical mirror or the convex lens for condensing can be installed, and the light amount at both right and left ends is large. is there.

Special reflector 5 in this known example, the light emitted from the point F, is reflected in the direction of opening outward at the central portion by an angle theta _m, reflects such that the light flux parallel to the optical axis in the left and right ends.

However, in the headlight of this known example (FIG. 6),
As shown in the light distribution pattern in FIG. 7A, the light amount near the center is insufficient.

As a reflector for a lamp improved to eliminate the disadvantages of each of the above-mentioned known examples and obtain an arbitrary light distribution characteristic,
No. 60-86502, a reflector for a lamp is known.

The reflector for a lamp disclosed in the above publication is disclosed in the sixth publication of the publication.
The angle θ with respect to the optical axis of the light incident from the light source toward the reflecting surface has a shape as shown in FIGS.
And the light intensity I ₀ of the light source and the angle α of the reflected light with respect to the optical axis are maintained in a relationship of −I ₀ cos θ = Asin α− (B + Aα) cos α + C, and the light emitted from the light source is at an angle θ The relation between the coordinates (X ₁ , Z ₁ ) of the incident point and the coordinates (X ₂ , Z ₂ ) of the incident point at the same angle θ + Δθ is and, And the angle θ is set to θ ≧ 0, the angle α is set to α ≦ 0, and the angle θ increases with the angle θ. α is set to decrease.

According to this known technique, the degree of freedom of the light distribution design in the left-right direction is increased as shown in FIG.
As shown in FIG. 9 of the publication, the light distribution pattern has a symmetrical shape both vertically and horizontally. Such a phenomenon is inevitable because the lamp reflecting mirror disclosed in the above publication is a rotating surface about the optical axis Z.

Such a circular light distribution pattern (FIG. 9 in the publication)
Although it is used as an auxiliary headlight, it is not suitable as a main headlight.

In view of the above circumstances, is uniformly illuminated with a range of lateral direction angle theta _m, and the auxiliary spherical mirror (e.g. FIG. 5 (4 shown in B)) can be used in combination with, optical headlight automobiles As a system, a light source is installed so as to face the reflecting surface of the concave mirror, and the shape of the reflecting surface and the position of the light source in the headlamp provided with a lens that covers the front opening of the concave mirror are configured as follows. Can be considered.

(A) the reflecting surface of the concave mirror has a shape formed by connecting a number of paraboloids of revolution that share a focal point; and (b) the center axis of each of the number of paraboloids of revolution is relative to the optical axis of the lamp. , meet at a horizontal plane, (c) the angle of intersection between the optical axis and the central axis, in the vicinity of the center portion of the concave mirror, left, tilted to the right sides by angle theta _m, intersection angle, left and right end portions of the concave mirror inclined in convergent direction by angle theta _m inward in, it has changed gradually during this period.

The above configuration is created by the present inventors and is being separately filed (see Japanese Patent Application Laid-Open No. 2-148601) (hereinafter referred to as the prior application).

According to the configuration of the above-mentioned prior application, the luminous flux coming out of the focal point and reflected by the paraboloid of revolution becomes parallel to the optical axis, so that the direction of the reflected light is the angle θ in the horizontal plane.
To the angle −θ.

Moreover, the central portion of the reflecting surface because the reflection diffusion direction of each corner theta _m to the left and right, the left, can be provided an auxiliary spherical mirror or lens in the scope of right each corner theta _m (range of angular 2 [Theta]) .

FIG. 7 shows a special reflector 6 in the optical system according to the invention of the prior application, FIG. 7 (A) is a schematic horizontal sectional view, and FIG. 7 (B) is an explanatory view thereof.

In FIG. 7 (B), Z is the optical axis of the lamp, and X is a horizontal axis orthogonal to the optical axis.

The point F is a focus, it is assumed parabolic P _b has a central axis Z _b which is inclined clockwise with respect to the optical axis Z.

Furthermore, the point F and focal, it is assumed parabolic P _h has a central axis Z _h inclined counterclockwise with respect to the optical axis Z.

Then, these rotational paraboloid P _b, sets the P _d, composite paraboloid by connecting to each other P _h, constituting the reflecting surface along the composite paraboloidal surface.

In FIG. 7 (B), three paraboloids of revolution have been set for convenience of explanation, but in FIG. 7 (A), eight paraboloids of revolution, left and right, are respectively defined. I set them and tied them together.

Z _a to Z _h in FIG. 7 (A) is the center axis of eight paraboloid respectively. A paraboloid of revolution (not shown) is assumed with the intersection point F of these eight central axes as the focal point.

The seventh diagram in (A), P _a is a portion of a paraboloid centered axis Z _a is the focus of F.

P _b is a portion of a paraboloid centered axis Z _b and focus the F.

P _c is a part of a paraboloid with F as the focus and Z _c as the central axis.

P _d is a part of a paraboloid having F as a focal point and Z _d as a central axis.

P _e is a portion of a paraboloid centered axis Z _e to focus the F.

P _f is a part of a paraboloid with F as the focal point and Z _f as the central axis.

P _g is a part of a paraboloid having F as a focal point and Z _g as a central axis.

P _h is a part of a paraboloid having F as a focal point and Z _h as a central axis.

Is emitted from a light source was allowed located at the focal point F (not shown), the light reflected respectively paraboloid P _a to P _h is arrow a
As ~ arrow h, in parallel to the reflection and the center axis Z _a to Z _h.

In this manner, the light emitted in each direction from the light source was allowed located at the focal point F (not shown) is left as shown by the arrow a~ same h, is diffused within the angle ± theta _m to the right.

The light of arrows a to _h reflected on the paraboloids of rotation P _{a to} Ph has a higher luminous flux density as light to the right as indicated by arrow a and a lower luminous flux density as light to the left as indicated by arrow h. The light distribution pattern is as shown in FIG.

In FIG. 7A, although the optical path is not shown in the left half of the figure, an optical path symmetrical with respect to the optical axis Z is formed.

Therefore, as shown in FIG. 8B, the light distribution pattern generated by the left half is different from that of FIG.

Therefore, the light distribution pattern of the entire headlamp of this example is
FIG. 8 (C), which is a combination of FIG. 8 (A) and FIG. 8 (B), provides a suitable light distribution characteristic.

That is, a uniform illuminance distribution within the angle theta _m in the left and right are obtained.

Further, as easily understood from FIG. 7 (A),
Since the optical path (arrows a to h) of the reflected light does not pass through the central front part of the special reflector of this embodiment, it is suitable for installing the auxiliary spherical mirror 4 as shown in FIG.

When features a convex lens for auxiliary spherical mirror 4 or condenser as in this embodiment (FIG. 9), the light flux ranging from a light source (located at the focal F) of the front corner 2 [Theta] _m can also be effectively utilized. When the invention of the prior application is applied, the light distribution pattern described with reference to FIG. 8 is obtained, so that the plain lens 8 can be used as the front lens.

[Problems to be solved by the invention]

As described above, according to the optical system according to the prior application of the invention, most of using a lens of plain, around the front of the headlight, uniform range at an angle theta _m with respect to the optical axis Z Can be illuminated.

Then, the auxiliary spherical mirror 4 shown in FIG. 9 is provided, or
If a converging convex lens (not shown) is provided at this position,
The direct luminous flux emitted from the light source and incident on the auxiliary spherical mirror or the convex lens can be effectively used.

When the convex lens is provided in front of the light source as described above, the results are as shown in FIGS. 10 (A) and (B). FIG. 9 is a schematic diagram illustrating a light source bulb 21 positioned at the focal point F of the special concave mirror 6 shown in FIG. 9 and a convex lens 22 arranged at the position of the auxiliary spherical mirror 4 shown in FIG. In the figure,
(A) is a side view, (B) is a rear view, and 23 is a socket.

Z is the optical axis of the special concave mirror 6, and F is the focal point.

Y is a vertical axis passing through the focal point F, and X, Y, and Z form three orthogonal axes.

The convex lens 22 emitted from the light source bulb 21 as shown by the arrow j
The incident light is substantially parallel to exit the optical axis Z as indicated by the arrow k ₁ in, but glare light as an arrow k _2, k ₃ (stray light) is generated.

If the front lens is now removed and the screen in front of the lamp is illuminated, a light distribution pattern as shown in FIG. 11 (A) is obtained.

VV is a vertical line on the screen, and HH is a horizontal line on the screen.

In this (A) Figure, downward said optical axis Z by an angle theta _s than horizontal, its extension is, V-V line and h-h
It passes through the intersection with the line.

Light arrows k ₁ of the form a high illuminance zone 25A.

In FIG. 10 (A), is incident on the convex lens 22 is emitted from the light source bulb 21, a light path of light substantially parallel to refracted to the optical axis Z of the previous indicated arrow j, present in many other than k ₁ . Light that reaches the screen via these multiple light paths forms an image of the filament of the light source bulb 21 on the screen.

FIG. 11 (A) depicts images of these many filaments. These many filament images overlap to form a high illuminance zone 25A.

The glare light of the arrows k ₂ and k ₃ shown in FIG.
A low illuminance zone 26A is formed around the high illuminance zone 25A described above with reference to FIG.

The low illuminance zone 26A has a lower illuminance than the high illuminance zone 25A, but a part of the low illuminance zone irradiates the area above the horizontal line HH, which may dazzle oncoming vehicles.

The present invention is a vehicle headlight that utilizes the above-mentioned prior invention and arranges a convex lens in front of the light source to effectively use the direct light incident on the convex lens,
It is an object of the present invention to provide a direct-type optical system that does not dazzle an oncoming vehicle due to the projection of a direct-light portion.

[Means for solving the problem]

In order to achieve the above object, the present invention has a light source bulb and a special concave mirror disposed behind the light source bulb, and the special concave mirror can control light emitted from the light source within a certain range. In the vehicle headlamp, which is a concave mirror having a part in which the reflected light does not pass in the central part while diffusely reflecting the reflected light as a whole and obtaining a substantially uniform left and right illuminance distribution within a certain angle range, A convex lens for capturing and emitting direct light from the light source is disposed in front of the light source, and the convex lens has a center line passing below the filament of the light source bulb, and the light of the concave mirror is provided. It is characterized by being inclined so as to intersect with the axis.

[Action]

According to the above configuration, the center line (center axis) of the convex lens located in front of the light source bulb passes below the filament through the light source bulb. That is, the central axis of the convex lens is inclined upward.

The light distribution pattern when the center line of the convex lens is horizontal and passes through the filament of the light source bulb is as shown in FIG. 11 (A) described above. However, when the center line of the convex lens is tilted upward, The light distribution pattern in FIG. 11A changes as shown in FIG.

A point O 'shown in FIG. 11 (B) is a point where the extension of the center line of the convex lens intersects the screen, and H'-H' is a horizontal line on the screen passing through the point O '.

As shown in FIG. 11 (B), when the convex lens is tilted upward, the low illuminance zone 26B generated by the glare light is deviated downward as compared with the high luminous intensity zone 25B, and the upper illuminating zone does not stick out.

〔Example〕

1 and 2 show an embodiment of a direct-type optical system according to the present invention.

FIG. 2 shows a horizontal sectional view (ZX sectional view), in which the present invention is applied to the configuration of FIG. 9 in the above-mentioned prior application, the auxiliary concave mirror 4 is replaced with a convex lens 22, and the transparent lens 8 is replaced. This is replaced by a diffusion type prism lens 24.

In the horizontal sectional view (FIG. 2), the center line of the convex lens 22 coincides with the optical axis Z of the special concave mirror 6.

FIG. 1 (A) is a side view showing the light source bulb 21 and the convex lens 22 in the above embodiment extracted and corresponding to FIG. 10 (A) in the invention of the prior application.

FIG. 1 (B) is a rear view of the present embodiment, corresponding to FIG. 10 (B) in the invention of the prior application.

Z shown in FIG. 1A is the optical axis of the special concave mirror 6 (see FIG. 2), and F is also the focal point.

In this example, the filament of the light source bulb 21 is disposed so as to pass through the focal point F and to be in the X-axis direction.

The center line mm of the convex lens is a point R at the front end of the convex lens 22.
, And is disposed so as to cross the optical axis Z and pass below the focal point F.

The line m'-m 'shown in the rear view of FIG. 1 (B) is a horizontal line parallel to the X axis passing through a point R' where the center line of the convex lens 22 intersects the rear surface of the convex lens.

Most of the light flux emitted from the light source bulb 21 as indicated by the arrow j and incident on the convex lens 22 and refracted is indicated by the arrow.
q Light is projected almost parallel to the optical axis Z of the special concave mirror as shown in ₁ .
Portion becomes the as glare light arrow q ₂ (stray light).

Glare light of the arrow q ₂ becomes a downward trend compared to the arrow q _1, no upward component.

Then, the main beam of the arrow q ₁ direction forms a high illuminance zone 25B shown in FIG. 11 (B), glare light of arrow q ₂ direction to form a low illuminance zones 26B.

Suppose now that the diffusion type prism lens 24 shown in FIG.
Remove the and illuminate the screen in front of the headlight,
A high illuminance zone 25B and a low illuminance zone 26B indicated by a two-dot chain line in FIG. 3 overlap each other.

When this projection light passes through the diffusion type prism lens 24, it is diffused in the left-right direction.

When the diffusion type prism lens 24 has a dimming function in a direction slightly converging in the vertical direction in addition to a diffusion function in the horizontal direction, the high illuminance zone 25B causes the high illuminance pattern 27 on the screen. The low illuminance zone 26B also forms a low illuminance pattern 28.

In this manner, the light distribution pattern constituted by the direct optical system that has passed through the convex lens 22 in the headlight of this embodiment is a light distribution pattern in which the high illuminance pattern 27 and the low illuminance pattern 28 shown in FIG. It has the right and left diffusion angles, and is not diffused significantly above the HH line, so that there is no danger of dazzling oncoming vehicles.

In FIG. 2, the light beam emitted from the light source bulb 21 and incident on the special concave mirror is provided with an appropriate diffusion angle in the left-right direction to form most of the light distribution pattern. The direct light component incident on the light source forms a high illuminance pattern 27 and a low illuminance pattern 28 shown in FIG. 3, and is effectively used without dazzling an oncoming vehicle.

[Effect of the invention]

When the direct optical system according to the present invention is applied to all or a part of a vehicle headlamp, the direct light beam emitted from the light source bulb and incident on the convex lens can be effectively used without dazzling an oncoming vehicle. Can be.

[Brief description of the drawings]

1 to 3 show an embodiment of the direct optics system according to the present invention. FIG. 1 (A) is a side view of a main part, FIG. 1 (B) is a rear view of a main part, and FIG. FIG. 3 is a diagram of a light distribution pattern. FIG. 4 to FIG. 6 are explanatory diagrams relating to the prior art. 7 to 11 are explanatory diagrams of the invention according to the prior application. DESCRIPTION OF SYMBOLS 1 ... Rotating parabolic mirror, 2 ... Prism lens, 3 ... Diffusion type reflector, 6 ... Special concave mirror to which the invention of prior application was applied, 8 ... Through lens, 21 ... Light source bulb, 22 ... Convex lens, 23 ... Bulb holder, 24 ... Diffuse prism lens, 27 ... High illuminance pattern, 28 ... Low illuminance pattern.

Claims (1)

(57) [Scope of request for utility model registration] 1. A light source bulb and a special concave mirror disposed behind the light source bulb, wherein the special concave mirror reflects light emitted from the light source by diffusing and reflecting right and left within a certain angle range. As a whole, an illuminance distribution substantially equal to the left and right can be obtained within a certain angle range as a whole light, and a vehicular headlamp which is a concave mirror having a portion through which reflected light does not pass in the center portion, in front of the light source, A convex lens that captures and emits direct light from the light source is provided, and the convex lens is inclined such that the center line passes below the filament of the light source bulb and intersects the optical axis of the concave mirror. A direct optics system for a vehicle headlamp.