DE102013213782A1 - Semiconductor lamp for a vehicle light - Google Patents

Abstract

The semiconductor lamp (1) is provided for a vehicle lamp and has a base (2, 2a, 2b) for connection to a lamp socket of the vehicle headlamp (W) and at least one carrier (5) connected to the socket (2, 2a, 2b) at least one semiconductor light source (7) arranged thereon, the carrier (5) being rotatable relative to the base (2, 2a, 2b) about an axis of rotation (D), the carrier (5) being mounted on at least two operating rotational positions (φ0, φ1 ) is adjustable about the axis of rotation (D) and the at least one semiconductor light source (7) with respect to the axis of rotation (D) asymmetric near field light distribution pattern (NF). A vehicle (K) comprising at least a pair of vehicle headlamps (W) for left and right vehicle halves each equipped with a semiconductor lamp (1) according to claim 2, said semiconductor lamps (1) having two mutually rotated by 180 ° Rotational positions (φ0, φ1).

Description

The invention relates to a semiconductor lamp for a vehicle lamp, comprising a base for connection to a lamp socket of the vehicle lamp and at least one carrier connected to the socket with at least one semiconductor light source arranged thereon. The invention further relates to a vehicle, comprising at least a pair of vehicle lights for a left and a right half of the vehicle, which are each equipped with a semiconductor lamp. The invention is particularly applicable to vehicle lights in the form of long-range headlights, e.g. for generating a high beam, a fog light, etc. The invention relates in particular to retrofit lamps, in particular for vehicle lights.

Incandescent and halogen lamps are increasingly being replaced by semiconductor lamps in many areas. For existing luminaires, for example luminaires on vehicles designed for operation with incandescent lamps, so-called LED retrofit lamps or "LED retrofits" are increasingly being offered, which include the corresponding types of incandescent lamps (eg H11, H8, H16. ..) replace. A problem in the design of such LED retrofits is, in addition to a heat dissipation, reaching a near-field light distribution, which is as close as possible to a near-field light distribution of the corresponding types of incandescent lamps. This is considered a prerequisite for achieving at least similar far-field light distribution of the luminaire as when operating with the envisaged types of incandescent lamps. However, a problem is a suitable cooling, since a suitable surface for attaching a heat sink surface is not available. As a result, LED retrofit lamps have either low light output and / or very complicated heat sinks.

It is the object of the present invention to overcome the disadvantages of the prior art at least partially, and in particular to provide a semiconductor lamp for a vehicle headlamp, which improved cooling compared to previous semiconductor lamps in a similar far-field light distribution as in the operation of vehicle lights, especially vehicle headlights , with conventional lamps allows.

This object is achieved according to the features of the independent claims. Preferred embodiments are in particular the dependent claims.

The object is achieved by a semiconductor lamp for a vehicle lamp, comprising a base for connection to a lamp socket of the vehicle lamp and at least one connected to the base carrier with at least one semiconductor light source disposed thereon, wherein the carrier relative to the base is rotatable about an axis of rotation, the carrier is adjustable to at least two operating rotational positions about the axis of rotation and the at least one semiconductor light source has an asymmetrical near field light distribution pattern with respect to the axis of rotation.

Thus, there is provided a semiconductor lamp by use of which a far-field light distribution pattern for a desired light function (e.g., low beam, high beam, foglight, etc.) can be generated. However, the near field light distribution pattern of this semiconductor lamp does not correspond to the symmetrical near field light distribution pattern of a conventional incandescent lamp. By dispensing with the symmetrical near field light distribution pattern, a larger heat sink can be placed close to the at least one semiconductor light source, which improves cooling. The improved cooling in turn, for example, higher luminous flux or a more compact design are possible. In particular, when using multiple semiconductor lamps and / or vehicle lights can be produced by superimposing the light distribution pattern of the vehicle lights with little or no additional effort, a desired far-field light distribution pattern.

This semiconductor lamp makes use of the fact that most of the light functions of a vehicle are only required in the far field (from about 5 m away from the semiconductor lamp), while a viewing of a light distribution pattern is required, for example. A vehicle headlamp in the near field (for example, up to a distance of about 5 m from the vehicle headlamp) rarely occurs. The deviation of the near field light distribution pattern between a conventional lamp and the semiconductor lamp according to the invention is thus for practical purposes, at least for certain light functions, such as e.g. Fog lights, negligible.

Preferably, the at least one semiconductor light source comprises at least one light-emitting diode. If several LEDs are present, they can be lit in the same color or in different colors. A color can be monochrome (eg red, green, blue etc.) or multichrome (eg white). The light emitted by the at least one light-emitting diode can also be an infrared light (IR LED) or an ultraviolet light (UV LED). Several light emitting diodes can produce a mixed light; eg a white mixed light. The at least one light-emitting diode may contain at least one wavelength-converting phosphor (conversion LED). The phosphor may alternatively or additionally be arranged remotely from the light-emitting diode (" The at least one light-emitting diode can be present in the form of at least one individually housed light-emitting diode or in the form of at least one LED chip Several LED chips can be mounted on a common substrate ("submount") at least one own and / or common optics for beam guidance, eg at least one Fresnel lens, collimator, etc. Instead of or in addition to inorganic light emitting diodes, eg based on InGaN or AlInGaP, organic LEDs (OLEDs, eg Alternatively, the at least one semiconductor light source can have, for example, at least one diode laser.

It is an embodiment that the semiconductor lamp is a semiconductor lamp for a vehicle lamp of a pair of vehicle lamps for left and right vehicle halves. Thus, the light distribution patterns of the two vehicle lights in the far field can be superimposed particularly easily to a conventional far-field light distribution pattern. The vehicle light may in this case be in particular a headlight.

In particular, for this purpose it is an advantageous embodiment that the semiconductor lamp has two mutually rotated by 180 ° about the axis of rotation rotational positions φ0 and φ1. In other words, the carrier with the semiconductor light sources is rotatable in particular by 180 °. Consequently, mirror-symmetrical light emission patterns can be set to one another on a semiconductor lamp. Thus, in particular mirror-symmetrical (e.g., on left and right vehicle halves), semiconductor lamps mounted in a vehicle can easily generate a desired far-field light distribution pattern. However, in principle also other (additional and / or alternative) operating rotational positions can be provided. Also, a free rotation may be provided. In particular, may be provided for installation in a particular vehicle light a certain operating rotational position.

It is a development that the base has a first, stationary part and a second, rotatable part, wherein the carrier is firmly connected to the second part of the base. In particular, an electrical contact element for electrical connection to a socket can be located on the first part. For example, the pedestal may have a label with indications of rotation (e.g., "recessed left", "recessed right").

It is yet an embodiment that by means of the at least one semiconductor light source, a sector around the axis of rotation is illuminated and outside of this sector at least one heat sink is arranged on the carrier. Thus, the heat sink can be brought close to the carrier without causing shading, in particular be attached to the carrier. The heat sink sits close, in particular only separated by the carrier, at the at least one semiconductor light source, which enables effective heat dissipation.

It is a development that the heat sink extends over the entire height (along an extension direction of the axis of rotation) of the carrier, which allows a particularly large-scale and thus effective heat transfer to the heat sink.

It is a further embodiment that the carrier is a plate-shaped carrier having a front side and a rear side, which is arranged at least one semiconductor light source on the front side and the at least one heat sink is arranged on the back. This allows a particularly simple, inexpensive and effectively cooling semiconductor lamp. The plate-shaped carrier may for example be a band-shaped carrier whose longitudinal axis is parallel to the axis of rotation, in particular may coincide with the axis of rotation.

However, the invention is not limited thereto, and the surface of the carrier carrying the at least one semiconductor light source may have any shape, e.g. curved, vielflächnerisch curved, etc. be. The orientation of the semiconductor light sources may therefore, e.g. in a planar arrangement, be the same or like, e.g. in angularly offset alignment of the semiconductor light sources, pointing in different directions.

It is yet another embodiment that the carrier extends parallel to the axis of rotation. The axis of rotation may extend to the carrier or run next to the carrier. However, the invention is not limited thereto and may be e.g. also have a (in particular with respect to its longitudinal axis) obliquely arranged carrier.

It is also an embodiment that the carrier protrudes from the base, in particular protruding on the front side. This facilitates a lateral light emission without or with only a slight shadowing of light, which, for example, allows a high-intensity irradiation of reflector surfaces of a vehicle lamp.

It is also an embodiment that the heat sink is continued on the side facing away from the carrier of the base. This allows a particularly effective heat dissipation through heat conduction. The heat sink may extend laterally past the base or through the base.

It is also an embodiment that the carrier is a heat spreading element. This enhances heat spread or heat dissipation from the at least one semiconductor light source. The carrier may be, for example, a ceramic carrier or a metal core board. The carrier may also have one or more heat pipes or "heatpipes" for this purpose.

It is also an embodiment that an emitter (upper) surface of the at least one semiconductor light source lies on the axis of rotation. This makes it possible to realize a very small emitter box. An axis of symmetry, for example a longitudinal axis, of the carrier may then be offset, in particular offset parallel to the axis of rotation. An "emitter box" may be understood as meaning, in particular, that spatial region of a vehicle lamp which is provided as a focal spot or focal region for a downstream optical system (for example having at least one reflector, lens, diaphragm, etc.), in particular a luminaire.

In order to achieve better visibility for external observers, it is also preferred in the near field for one or more additional semiconductor light sources to be used, which serve to generate a scattered light (also referred to below as "scattered-light semiconductor light sources") In particular, the stray light semiconductor light source may be disposed outside the emitter box, and the at least one stray light semiconductor light source may radiate into a non-illuminated space portion of the other semiconductor light sources (which generate the desired far-field light emission pattern.) In particular, a stray light semiconductor light source may have a smaller luminous flux In the case of a disc-shaped carrier, the at least one semiconductor light source generating the far-field light-emitting pattern may be generated (less brightly lit) than a far-field light-emitting pattern generating semiconductor light source one side (e.g. on a front side) of the carrier (in particular within the emitter box), and the at least one scattered light semiconductor light source may be arranged on this side (in particular outside the emitter box) and / or on the side facing away from it.

It is still an embodiment that the semiconductor lamp is a incandescent retrofit lamp, a gas discharge lamp retrofit lamp or a halogen lamp retrofit lamp. These are often used in vehicles, so that the invention is particularly advantageous in this case.

It is also a further embodiment that the vehicle lamp is a headlight. The headlight may in particular be a fog light or a headlight for high beam. In particular, these headlights are characterized by the fact that their appearance plays a minor role when switched on.

The object is also achieved by a vehicle, comprising at least a pair of vehicle lights, in particular headlights, in particular for a left and a right half of the vehicle, in particular a motor vehicle, which are each equipped with at least one semiconductor lamp as described above, wherein the semiconductor lamps two to each other Having 180 ° twisted operating rotational positions. Thus, a desired superimposition of light distribution patterns of these vehicle lights can be provided in a particularly simple manner with little or no additional effort. In particular, this arrangement can be achieved by the same LED lamps, which reduces manufacturing costs.

The above-described characteristics, features, and advantages of this invention, as well as the manner in which they will be achieved, will become clearer and more clearly understood in connection with the following schematic description of exemplary embodiments which will be described in detail in conjunction with the drawings. In this case, the same or equivalent elements may be provided with the same reference numerals for clarity.

1 shows a side view of a semiconductor lamp according to a first embodiment;

2 shows the semiconductor lamp according to the first embodiment in plan view;

3 shows the semiconductor lamp according to the first embodiment in a front view;

4 shows a side view of a semiconductor lamp according to a second embodiment;

5 shows a side view of a semiconductor lamp according to a third embodiment; and

6 shows in plan view a vehicle with two semiconductor lamps according to one of the embodiments.

1 shows a side view of a semiconductor lamp in the form of a LED retrofit lamp 1 according to a first embodiment. 2 shows the LED retrofit lamp 1 in plan view. 3 shows the LED retrofit lamp 1 in frontal view.

The LED retrofit lamp 1 is for installation in a vehicle lamp in the form of a Vehicle headlamp W of a motor vehicle K provided, as described below with respect to 6 is explained. LED retrofit 1 has a pedestal 2 for connection to a lamp socket of the vehicle headlight W on. In particular, it may be an incandescent retrofit lamp or a gas discharge lamp retrofit lamp.

The base 2 has here purely by way of example a laterally projecting electrical contact element 3 which can be brought into engagement with a corresponding contact counter element of the lamp socket. However, all other types of sockets or electrical contact elements are also usable, for example a bipin socket, etc. The base 2 may have a cooling structure on the outside. The base 2 may also serve as a receptacle for a driver (not shown), which driver is adapted to the electrical contact element 3 to convert recorded electrical signals into electrical signals suitable for the operation of a semiconductor light source.

The base 2 is in two parts with a first part 2a , which is the electrical contact element 3 has and when installed in the lamp holder is stationary to the motor vehicle K, as well as a rotatable about a rotation axis D rotatably connected second part 2 B , The first part 2a and the second part 2 B are indicated here by dashed lines separately. The second part 2 B is as indicated by the double arrow in 2 indicated, rotatable by 180 ° about the rotation axis D, from an operating rotational position in the form of a first end position φ0 = 0 ° to an operating rotational position in the form of a second end position φ1 = 180 °. The second part 2 B May be releasably lockable with the first part in the end positions φ0, φ1. In principle, other rotational positions may also be assumed, for example other end positions φ0, φ1 can be specified and / or intermediate positions can be set therebetween. Also like the second part 2 B free in the first part 2a be rotatable, so can also take rotational positions φ> = 360 °.

At a front 4 of the second part 2 B of the pedestal 2 is perpendicular to a light source carrier 5 arranged in the form of a plate-shaped, in particular band-shaped metal core board. The light source carrier 5 So stands from the pedestal 2 forward. The light source carrier 5 like for example with the second part 2 B of the pedestal 2 jammed, screwed, riveted and / or glued etc. be. The light source carrier 5 So makes a rotation of the second part 2 B with, wherein a longitudinal axis L of the light source carrier 5 here with the axis of rotation D of the second part 2 B coincides. The light source carrier 5 thus extends parallel to the axis of rotation D.

On one side of the light source carrier 5 , which in the following without limitation of the general public as the front 6 are designated, are several, here exemplified three, semiconductor light sources in the form of eg LEDs 7 appropriate. The LEDs 7 for example, emit white light. The LEDs 7 are within an emitter box below 8th designated area corresponding to an (extended) focal spot or focal area of the vehicle headlight W. The LEDs 7 So should be within the emitter box 8th so that the vehicle headlights W produce the desired Lichtabstrahlmuster at least in the far field. The emitter box 8th In particular, the regulations for the respective to be replaced conventional lamp can be selected accordingly. Since here the longitudinal axis L of the light source carrier 5 coincides with the axis of rotation D, the emitter (upper) surfaces 13 the LEDs 7 offset or spaced to the rotation axis D.

The LEDs 7 can be provided with primary optics (not shown), the introduction of further optical elements in the beam path is also possible.

The LEDs 7 generate an asymmetrical near-field light distribution pattern of the vehicle headlamp W, as they only in the half space in front of the front 6 of the light source carrier 5 radiate. The LEDs 7 In other words, they can illuminate only a semispace-shaped sector about the longitudinal axis L, while in a complementary half-space, which in front of a back 9 of the light source carrier 5 is located, no light is emitted. By switching the rotational position between the end positions φ0, φ1 becomes one to a plane through the axis of rotation D, in particular to the plate plane of the light source carrier 5 , mirror-symmetric light emission achieved.

In operation of the LEDs 7 can their waste heat by serving as a heat spreader (also referred to as "Heatslug") light source carrier 5 distributed over a large area.

The light source carrier 5 likes of a translucent (transparent or diffusely dispersing) piston 10 be covered. The piston 10 may be covered, for example, with phosphor for wavelength conversion. The piston 10 may have air vents (not shown), eg air vents.

Also like to the light source carrier 5 one or more additional stray light LEDs 11 be present, but not like the LEDs 7 serve to form the functional Lichtabstrahlmusters, but to generate a scattered light, eg for better visibility in the near field, for example by pedestrians. The at least one stray light LED 11 especially at the front 6 and / or at the back 9 of the light source carrier 5 be arranged, in particular outside the emitter box 8th , The at least one stray light LED 11 especially like in one of the ("main") LEDs 7 emit a non-illuminated room area to create stray light. The at least one stray light LED 11 may in particular be arranged and arranged in the "shadow" of the main LEDs 7 lying reflector surfaces of the vehicle headlight W to illuminate. A stray light LED 11 may be identical or different to a (main) LED 7 be educated.

For additional cooling like in the socket 2 a fan 12 be blocked, as indicated by dashed lines. The fan 12 For example, like a cooling air flow over the LEDs 7 , the light source carrier 5 and / or a heat sink (such as in 4 shown).

4 shows a side view of a semiconductor lamp in the form of a LED retrofit lamp 21 according to a second embodiment. The LED retrofit lamp 21 is similar to the LED retrofit lamp 1 constructed according to the first embodiment and differs from it by one at the back 9 of the light source carrier 5 arranged heat sink 22 , This allows a large-scale heat dissipation of the light source carrier 5 near the LEDs 7 What a particularly good cooling of the LEDs 7 allows. This allows particularly bright LEDs 7 be used. The heat sink 22 shades that from the LEDs 7 produced light not because it is located in the rear half space, which of the LEDs 7 is not irradiated.

Such an arrangement of the heat sink 22 would not be possible with a symmetrical light emission. If you wanted to achieve a radiation in the entire solid angle (as in the conventional approach), you would be limited in this respect, as one equipped with LEDs on both sides, serving as a heat spreader light source carrier 5 for efficient heat dissipation should have a certain width, creating small emitter boxes 8th become impossible. If you have the light source carrier 5 On the other hand makes very narrow, this represents a limit for the dissipated heat output and the maximum LED luminous flux.

The heat sink 22 can at the the light source carrier 5 opposite side of the base 2 be continued, for example by passing through the base 2 in particular through its second part 2 B , is passed through. As a result, a particularly effective heat dissipation can be achieved.

5 shows in side view a LED retrofit lamp 31 according to a third embodiment. The LED retrofit lamp 31 is similar to the LED retrofit lamp 1 constructed according to the first embodiment and differs from it by a offset from the axis of rotation D light source carrier 5 , In other words, fall the longitudinal axis L of the light source carrier 5 and the rotation axis D no longer on each other, but are offset parallel to each other. This offset is such that the emitter surfaces 13 the LEDs 7 lie on the axis of rotation D. Upon rotation of the light source carrier 5 remain the emitter surfaces 13 the LEDs 7 lie on the axis of rotation D, leaving the emitter box 32 can be chosen particularly small. This in turn allows in a simple way a sharp Lichtabstrahlmuster behind the vehicle headlights W.

6 shows in plan view the motor vehicle K with two vehicle headlights W, which are each equipped with a LED retrofit lamp according to the invention, in particular with one of the LED retrofit lamps 1 . 11 or 21 according to one of the embodiments shown. The vehicle headlamp W is an example of a front fog headlamp, the appearance of which plays a minor role in the on state. The vehicle headlights W constitute a pair of vehicle headlights W for left and right vehicle halves. The vehicle headlights W can in particular be conventional vehicle headlights W and have at least one or more reflectors (not shown).

That of the built-in LED retrofit lamp 1 . 21 or 31 (especially within the emitter box 8th ) emitted light strikes at least partially on the at least one reflector and is then emitted to the outside. The light emitted from the vehicle headlights W generates a light-emitting pattern which differs markedly in the near-field NF from a light-emitting pattern when using a conventional symmetrical-emitting lamp.

The LED retrofit lamps installed in the left and right vehicle headlights W 1 . 21 or 31 have in particular two mutually rotated by 180 ° operating rotational positions φ0 and φ1, so that their Lichtabstrahlmuster to a plane through the center M of the motor vehicle K is mirror-symmetrical. Consequently, the light emission pattern of the vehicle headlights W are also at least roughly mirror-symmetrical, with a mirror-symmetrical design of the associated optical elements (including the at least one reflector, at least one lens, at least one aperture, etc.) of the vehicle headlamp W also exactly mirror-symmetrical.

In the far field FF (eg from a distance of 5 m from the vehicle headlights W) superimpose the Lichtabstrahlmuster the two vehicle headlights W and produce a sum Lichtabstrahlmuster which is similar to the local Sum-Lichtabstrahlmuster when using conventional lamps, in particular functionally equivalent and / or is practically the same.

Although the invention has been further illustrated and described in detail by the illustrated embodiments, the invention is not so limited and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention.

In particular, features of the different embodiments can be used alternatively or in combination, in particular also with the features of the invention described in the introduction. Thus, a lamp according to the third embodiment with the offset to the axis of rotation light source carrier, for example, a heat sink according to the second embodiment and / or a piston according to the first embodiment. Also, a laser may be used instead of an LED, etc.

Generally, "on", "an", etc. may be taken to mean a singular or a plurality, in particular in the sense of "at least one" or "one or more" etc., unless this is explicitly excluded, e.g. by the expression "exactly one", etc.

Also, a number may include exactly the specified number as well as a usual tolerance range, as long as this is not explicitly excluded.

LIST OF REFERENCE NUMBERS

1

LED retrofit

2

base

2a

first part of the socket

2 B

second part of the base

3

electrical contact element

4

front

5

Light source carrier

6

Front of the light source carrier

7

LED

8th

Emitter Box

9

Rear of the light source carrier

10

piston

11

Scattered light LED

12

Fan

13

emitter surface

21

LED retrofit

22

heatsink

31

LED retrofit

32

Emitter Box

D

axis of rotation

FF

far field

K

motor vehicle

L

Longitudinal axis of the light source carrier

M

center

NH

near field

φ0

first end position

φ1

second end position

W

vehicle headlights

Claims (13)

Semiconductor lamp ( 1 ; 21 ; 31 ) for a vehicle lamp, comprising - a base ( 2 . 2a . 2 B ) for connection to a lamp socket of the vehicle headlight (W) and - at least one with the base ( 2 . 2a . 2 B ) associated carriers ( 5 ) with at least one semiconductor light source ( 7 ), wherein - the carrier ( 5 ) opposite the base ( 2 . 2a . 2 B ) is rotatable about a rotation axis (D), - the carrier ( 5 ) is adjustable to at least two operating rotational positions (φ0, φ1) about the axis of rotation (D) and - the at least one semiconductor light source ( 7 ) has an asymmetrical near field light distribution pattern (NF) with respect to the rotation axis (D). Semiconductor lamp ( 1 ; 21 ; 31 ) according to claim 1, wherein the semiconductor lamp ( 1 ) has two mutually rotated by 180 ° about the rotational axis (D) operating rotational positions (φ0, φ1). Semiconductor lamp ( 21 ) according to one of the preceding claims, wherein by means of the at least one semiconductor light source ( 7 ) a sector can be illuminated around the axis of rotation (D) and outside this sector on the support ( 5 ) at least one heat sink ( 22 ) is arranged. Semiconductor lamp ( 21 ) according to claim 3, wherein the carrier ( 5 ) a plate-shaped carrier with a front side ( 6 ) and a back ( 9 ), the at least one semiconductor light source ( 7 ) on the front side ( 6 ) is arranged and the at least one heat sink ( 22 ) on the back ( 9 ) is arranged. Semiconductor lamp ( 1 ; 21 ; 31 ) according to claim 4, wherein the carrier ( 5 ) extends parallel to the axis of rotation (D). Semiconductor lamp ( 21 ) according to one of claims 3 to 5, wherein the heat sink ( 22 ) at the carrier ( 5 ) facing away from the base ( 2 . 2a . 2 B ) is continued. Semiconductor lamp ( 1 ; 21 ; 31 ) according to any one of the preceding claims, wherein the carrier ( 5 ) from the base ( 2 . 2a . 2 B ) protrudes. Semiconductor lamp ( 1 ; 21 ; 31 ) according to any one of the preceding claims, wherein the carrier ( 5 ) is a Wärmespreizelement. Semiconductor lamp ( 31 ) according to one of the preceding claims, wherein an emitter surface ( 13 ) of the at least one semiconductor light source ( 7 ) lies on the axis of rotation (D). Semiconductor lamp ( 1 ; 21 ; 31 ) according to one of the preceding claims, wherein the semiconductor lamp ( 1 ) is an incandescent retrofit lamp, a gas discharge lamp retrofit lamp or a halogen lamp retrofit lamp. Semiconductor lamp ( 1 ) according to one of the preceding claims, wherein the semiconductor lamp ( 1 ) is a semiconductor lamp for a vehicle lamp (W) of a pair of vehicle lamps (W) for left and right vehicle halves. Semiconductor lamp ( 1 ) according to one of the preceding claims, wherein the vehicle lamp (W) is a vehicle headlight (W), in particular a fog light. Vehicle (K) comprising at least one pair of vehicle headlights (W) for left and right vehicle halves, which are each provided with a semiconductor lamp ( 1 ; 21 ; 31 ) are equipped according to claim 2, wherein the semiconductor lamps ( 1 ) having two mutually rotated by 180 ° operating rotational positions (φ0, φ1).

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