[0001] This invention relates to a lamp for motor vehicles with a reflector having a basic
geometric surface spherical, paraboloidal, ellipsoidal or hyperboloidal and it is
provided with convex or concave basic reflexive elements. The working surface of the
basic reflexive elements is of Bézier's type or this surface has the shape of a circle
or an ellipse in horizontal and vertical section. The basic surface is provided with
concentrating reflexive elements in all or in part of all corners of the basic reflexive
elements. The lamp is destined to be used for signalisation of position and movement
of a motor vehicle. In this lamp, creating of a concentrated luminous intensity distribution
with increased luminous intensity into the direction with the highest probability
and frequency of effective signalization that is into the direction around the lamp
reference axis is solved.
[0002] Classical lamps with a reflector formed by a smooth parabola and with optics on refractor
or with optics formed by basic reflexive elements on reflector are characterized in
having a flat curve of luminous intensity distribution that may not be able to provide
an optimal reaction of an observer to the lamp signalization.
[0003] The above mentioned drawbacks are removed in case of a lamp according to the present
invention, which is comprised of a reflector, a refractor and a light source, whereby,
said reflector having its basic surface spherical, paraboloidal, ellipsoidal or hyperboloidal,
is provided with convex or concave basic reflective elements. Corners of said basic
reflexive elements are placed on the basic reflector surface, the working surface
of said basic reflective elements is of Bézier's type or this surface has a shape
of a circle or an ellipse in the horizontal and vertical sections. In the corners
of said basic reflexive elements said reflector is provided with concentration elements.
The reflexive surface of said concentration elements has the creating curve in a conic
shape, whereby, said curve can be rotationally symmetrical or it is cylindrical, toroidal
or in the shape of parabolic cylindres with horizontal or vertical position of the
cylinder axis. The refractor is provided with optical elements of low deviation or
with decorative optics on the functional surface, eventually with optical elements
with vertical, horizontal or vertical and horizontal deviation. Said light source
is in the shape of a cylinder which is placed laterally in the vicinity of the relector
focus.
[0004] It is an advantage of this solution that in case of sufficiently small dimensions
of the basic and the concentration elements, a good uniformity of brightness distribution
along the light emitting lamp surface and this also in case of observing its signalization
from the side spaces of visibility is obtained. Luminous intensity in the direction
around the reference axis is significantly increased to the detriment of the side
areas of the light beam, where there is a lover probability and registration rate
of the lamp light signal, what makes possible to fulfil the demanding photometrical
requirements set e.g. for the front direction indicating lamps, mounted in the vicinity
of the light-emitting surfaces of the main headlamps, for the rear fog lamps, where,
according to the present invention, it is possible to increase luminous intensity
in horizontal and vertical sections by means of a linear ray deviation away from the
normal line to the horizontal and vertical surfaces of the concentrating reflexive
elements or for the rear break and position lamps.
[0005] The invention is further illustrated with reference to the accompanying drawings,
in which Figure 1 shows a lamp in front view. Figure 2 shows a lamp in vertical section
made along the plane A-A as shown in Figure 1 and Figure 3 shows a light beam of the
lamp in projection into the perspective road projection.
[0006] A lamp for motor vehicles according to Figure 1 is comprised of a reflector
1, a refractor
2 and a source
3, e.g. of cylindrical shape mounted laterally with regard to the axis
x of the lamp in the vicinity of the focus
F of the reflector
1. The reflector
1 having its basic surface
10 spherical, paraboloidal, ellipsoidal or hyperboloidal is provided with convex of
concave basic reflexive elements
5 so that the corners
6 of the basic reflexive elements
5 are placed on the basic surface
10 of the reflector
1.
[0007] The working surface
16 of the basic reflexive elements
5 is of Bézier's type or this surface
16 has the shape of a circle or an ellipse in horizontal and vertical sections. In all
or in a part of corners
6 of the basic reflective elements
5 the reflector
1 is provided with concentration elements
4 so that they do not rest on the basic surface
10 of the reflector
1. The vertical dimension
θvk of the concentration elements
4 is smaller or equal to the vertical dimension
θvp of the basic reflexive elements
5
and the horizontal dimension
θHK of concentrating reflexive elements
4 is smaller or equal to the horizontal dimension
θHP of the basic reflexive elements
5.
[0008] If we neglect dimension of the elementary image of the light source
3 by reflector
1, the light beam is concentrated by reflection on the reflector
1 with the-basic reflective elements
5 after passage through the refractor
2 is geometrically similar to their shape in front view, that is, it is in shape of
a rectangle or a square in projection on the normal plane of projection according
to Figure 3, in case of surfaces of the Bézier's type it can be also of another shape.
In the corners
6 of the basic reflexive elements
5 the ray deviation off the normal lines to the basic surface
10 is maximal and the light source
3 is imaged from this place by the refractor
2 into the corner areas of the light beam, where it is generally not necessary to have
such a high luminous intensity as it is the case in the area around the reference
axis
14 of the lamp. Therefore, the concentration elements
4 are formed here outside the basic surface
10 of the reflector
1 with a smaller ray deviation off the normal line to the basic surface
10, which is in case of the same profile lover because of lower 9HV.K dimensions of
the concentration elements
4 in comparison to the dimensions 9HV.P of the basic reflexive elements
5. The reflexive surface of the concentration elements
11 is cylindrical, toroidal or in the shape of parabolic cylinders with vertical axis
position, whereby, the the area
7 around the horizontal line H-H is strengthened by a linear ray deviation off the
normal line to the basic surface
10 and or a horizontal position of the axis, whereby, the area
8 around the vertical line V-V is strengthened, or this surface is a three dimensional
one with a creating curve in the shape of conics and can be in a special case eventually
rotationally symmetric, whereby vertical and horizontal deviations of the ray off
the normal line to the basic surface
10 into the area
9 around the lamp reference axis is obtained. Thereby, luminance distribution is maintained
on the light emitting surface into the space around the lamp reference axis
14 is increased, whereby good uniformity of luminous intensity distribution is maintained
on the lighr radiating surface of the lamp. That makes possible to increase speed
and probability of registration of the optical lamp signalization and, thereby, also
an increase of road traffic safety and obtaining of the needed optic comfort during
observing of such a lamp.
[0009] A lamp for motor vehicles according to the present invention is applicable in illumination
systems of motor vehicles operated on ground communications.
1. A lamp for motor vehicles comprised of a reflector, a refractor and a source of light,
characterized in that said reflector (1) having the basic surface <10) spherical.
ellipsoidal, paraboloidal or hyperboloidal is provided with convex or concave basic
reflexive elements (5) having their working surface (16) of Bézier's type or it is
a circle or a sphere in horizontal and vertical sections, and in corners (6) of the
basic reflexive elements (5) it is provideded with concentration reflexive elements
(4) that have their vertical dimension (θvk) smaller or equal to the vertical dimension (θvp) of basic reflexive elements (5) and their horizontal dimension (θHk) is smaller or equal to the horizontal dimension (θHP) of the basic reflexive elements (5).
2. A lamp according to claim 1, characterized in that said reflexive surface (11) of
concentrating reflexive elements (4) has the creating curves in the shape of conics.
3. A lamp according to claims 1 and 2 characterized in that said reflexive surface (11)
of said concentration elements (5) is of cylindrical or toroidal shape or in the shape
of a parabolic cylinder with the vertical or the horizontal cylinder axis position.
4. A lamp according to claims 1, 2 or 3, characterized in that said refractor (2) is
provided with optical elements (15) of low deviation or decorative optics on its functional
surface (12).
5. A lamp according to claim 1, 2, 3 and 4, characterized in that on the functional surface
(12) the refractor (2) is provided with optical elements (15) having either vertical
or horizontal or both vertical and horizontal deviations.
6. A lamp according to claims 1, 2, 3, 4 and 5, characterised in that said light source
(3) is of cylindrical shape with the cylinder axis situated laterally with regard
to the lamp axis (14) in the vicinity of the focus (F) of the reflector (1).
