DE102004007211B4 - Signalers and bulbs - Google Patents

Abstract

signaler with a light (9) generating light source (4), the plurality from in a row next to each other on a support plate (5) arranged light-emitting elements (6), wherein the signal transmitter (1) exactly such a luminous means (4) characterized in that that the light source (4) LED chips as light-emitting elements and an optical element (18) which surrounds the LED chips (6) of the carrier plate (5) is arranged downstream of and fixed to the support plate (5).

Description

The The invention relates to a signal generator according to the preamble of the claim 1 and a lamp according to the preamble of patent claim 15.

such Signalers are used, for example, in traffic lights as in the street or Railway traffic used. With regard to these applications often need certain norms like the European one Standard EN 12368 or its associated German bridge standard DIN 67527-1 fulfilled become. In particular, this applies to the requirements for brightness regulated in these standards of the signal generator, its phantom light class or its light distribution. The phantom light class indicates how the signal generator across from incident external light, such as sunlight behaves. The higher the Phantom light class is, the less will be from the on the signal generator incident solar radiation again out of the signal generator out reflected. The less sunlight is reflected back from the signal generator, the better is a signal light generated by the signal generator, in particular at low position of the sun, recognizable. In the above standards are specified the requirements that a signal generator for each Fulfill phantom light class got to. Of the Color locus of a signal light emitted by the signal generator, for example, may conform to the respective above mentioned standard Do not significantly change sunlight.

In the EP 1 107 210 A2 a signal generator is described in which a plurality of LEDs are used in a zone arrangement as a lighting means. There, each of these LEDs contains an optical component, which is arranged downstream of the radiation-emitting semiconductor diode structure.

In the EP 1 091 167 A2 a signal generator is described, which has a housing in which a plurality of lighting means are arranged spatially separated from each other in a two-dimensional arrangement. Each illuminant is assigned a condenser, which parallelizes the part of the light generated by the respective illuminant which impinges on the condenser. The respective lighting means consists of a one-row arrangement of LED chips next to each other. Usually, a plurality of such bulbs are provided in the signal generator to meet the requirements regarding the brightness or the desired light distribution for traffic lights.

Around To ensure sufficient brightness of the signal generator, the condensers and the Illuminants are arranged in a certain way to each other and the condensers should be complete adjacent to each other, thereby reducing the effort in the production of the signal generator elevated becomes.

The Plurality of lamps should continue to be connected in such a way that at Failure of one or more LED chips the radiation characteristic of the signal generator not relevant is worsened. Again, this can be a relatively high cost require, so that the Production of such a signal generator comparatively expensive is. Such an interconnection requires, for example, the interconnection of LED chips in different bulbs with each other.

A two-dimensional arrangement of a plurality of such lamps elevated the danger of that because of the areal two-dimensional arrangement of extraneous light hits the bulbs, the color locus of the signal light and / or the phantom light properties adversely affected.

Further are the ones in conventional Signalers provided bulbs often matched to the signal generator. Often, such a lamp emits, for example, one large part of the luminous flux generated by the LED chips in solid angle ranges in which the light hits the housing of the signal generator. Is this case but partially to achieve optimal phantom light properties formed absorbent, so can the striking on the housing Do not leave the signal light. In particular, the absorbed Do not light on a condenser downstream of the light source meet and the efficiency of the signal generator is adversely reduced.

task The invention is to a signal generator and a lighting means of Specify mentioned type, the simple and inexpensive to produce are.

These The object is achieved by a Signal transmitter with the features of claim 1 respectively by a luminous means having the features of patent claim 15 solved.

One inventive signal generator has a light-emitting bulb, which is a plurality from arranged in a row next to each other on a support plate LED chips includes, wherein the signal transmitter has exactly such a light source. The light generated by the luminous means is preferably a signal light, for the the signal generator is provided and the light-emitting means is particularly preferred the only existing in the signal generator light source, this signal light generated.

Of the Signal transmitter preferably designed as a retrofit, for example fitted in a conventional traffic light housing can be.

One Such signal generator is easier to manufacture, since only one light source connected and in a housing, which may include the signal generator, arranged and / or fixed must become. This light source is advantageously designed that the signal transmitter used, for example, in a traffic light system at least those regulations according to the standards EN 12368 and DIN 67527-1 Fulfills, which the uniformity the luminance or the phantom light properties - for example Phantom light class 4 or 5 - the Concerning signaling device, with a single such light source fulfill can. In particular, an inventive signal transmitter with a diameter the light exit surface of 300mm the 1:10 requirements of EN 12368 regarding the uniformity the luminance for 200mm signal generator meet. The relationship the smallest to the largest luminance within the luminous field diameter of the signal transmitter may after the EN 12368 for 300mm sounder not smaller than 1:15 and for 200mm sounder not smaller be 1:10.

The Production costs of such a signal generator can - due lower electrical contacting costs because of reduced number and lower cost of the bulbs - so compared to one usual Signaling device with several two-dimensionally arranged light sources be reduced advantageous.

Further can the impact area of the bulb for incident extraneous light by preferably substantially one-dimensional Row arrangement of the LED chips are advantageously kept low. This can have a positive effect on the phantom light properties of the signal generator impact.

In A preferred embodiment of the signal generator is the lighting means downstream of a condenser, which generates the part of the light source Light rays that hits the condenser, preferably at least partially parallel, bundles. The illuminant is preferably in a focus or a Focal area, which may include the focus of the condenser arranged. The signal generator comprises prefers exactly one of the lamps associated condenser, the particularly preferably has exactly one focus, in which arranged the light source is. The raised Effort by tuning the arrangement of a plurality of condensers arises on a plurality of bulbs, may be advantageous be reduced.

In Another preferred embodiment of the signal generator is the Condenser of the bulb looked at least one scattering element downstream. This scattering element preferably scatters from the light source generated and striking from the condenser on the scattering light beams in the direction of a signal plane. The signal level is preferred substantially perpendicular to a plane surrounding the carrier plate arranged and more preferably spaced from the row of LED chips. For example, the signal level at one for a traffic light system in traffic provided signal generator be given by the street level.

In an advantageous development of the scattering element is the of the opposite of the bulb Side scattered on the scattering element scattered in such a way that the proportion of extraneous light that strikes the illuminant is reduced compared with a signal generator without scattering element. The scattering of the extraneous light is preferably also like the Scattering of the signal light in the direction of the signal plane. With advantage become thereby the Phantomlichteigenschaften of the signal generator, which by on the LED chips or the carrier plate incident extraneous light can be adversely affected.

By an absorbent material onto which the extraneous light, such as Sunlight, at least partially hits and that concerning the Is designed to absorb extraneous light, the phantom light properties be further improved the signal generator. This absorption material For example, in a housing enclosed by the signal generator, preferably on its surface, be arranged. The housing protects the bulb from harmful external influences and may include, for example, the scattering element and a housing body, wherein the scattering element is preferably a part of the light exit surface of Signal light is and the absorbent material preferably on the surface arranged the housing body is.

A one-row arrangement of the LED chips on the carrier plate is re the phantom light properties of particular advantage since compared so with a multi-line line arrangement of the LED chips, the area for incident extraneous light can be advantageously kept low. With advantage become so the Improved phantom light characteristics of the signaler.

The Illuminant preferably comprises eight, more preferably six, or less LED chips that are in a single row arrangement the carrier plate can be arranged. This can have advantages in terms of the radiation characteristic of the signal generator, especially in the horizontal direction.

There the signal transmitter only one light source with a plurality of in one Row side by side on a support plate arranged LED chips is the behavior of the bulb in case of failure of LED chips of more relevant Meaning of the signal generator.

The common The result of a failure of a single LED chip is the interruption the flow of current through the LED chip, a so-called open-contact. Far less common is a failure of an LED chip due to short circuit, in which over the shorted LED chip Electricity can flow.

At least in the former case, an interruption of the flow of current through the failed LED chip, the signaler should be within a reliable Remain area. By reliable is understood here, that yourself either does not significantly change the emission characteristics of the signal light or at a relevant Deterioration or change the emission characteristics of the signal light after the failure of a LED the whole signal generator or the complete light source fails. It should therefore be avoided that the signal generator in a partial failure the LEDs outside its specifications will continue to operate without this being Outside is immediately recognizable. A significant influence on the emission characteristics can be present, for example, if the signal generated by the signal generator Signal light perceptible dark areas or complete dark zones having.

In Another preferred embodiment of the invention is the lighting means Therefore, designed so that the Signal transmitter in the event of failure of an LED chip, in particular with a open-contact, within a reliable area remains.

In In a first advantageous development, the LED chips are placed on the carrier plate, For example, as a printed circuit board such as a PCB (printed circuit board) may be, at least partially connected in series with each other. Prefers The LED chips are connected in series with each other so that in the case the interruption of the current flow through an LED chip the entire Bulbs fail, so that the signal generator, by failure of the entire bulb, remains in the reliable area.

In In a second advantageous development, the LED chips are on the carrier plate at least partially interconnected in parallel. If the current flow through interrupted a LED chip, so increased in consequence the current flow through the LED chips connected in parallel to the failed LED chip. An elevated one Current flow through a LED chip leads usually to an increased Brightness of the light generated by the LED chip. Despite the failure a LED chip can be achieved with advantage that the Overall brightness of the signal generator not significantly reduced. The brightness increase occurs, however, in essentially all non-defaulted and parallel to the failed switched LED chips on.

In In a further advantageous development, the LED chips are on the carrier plate partially parallel to each other and partially connected in series with each other. At least two LED chips are preferred in a parallel block interconnected in parallel. Several of these parallel blocks can be found in Series on the carrier plate be interconnected. Particularly preferred is in a series circuit at least two such parallel blocks these parallel blocks no LED chip serially interposed, causing a failure of the complete bulb when interrupting the flow of current through a failed serial Interposed LED chip can be advantageously avoided. Furthermore, they are in a parallel block parallel LED chip preferred as possible adjacent to the support plate arranged. Is in case of failure of an LED chip in such Parallel block the current flow through interrupted the failed LED chip, so the increase in the current leads to the failed chip in parallel LED chips to increase the Brightness in the region of the carrier plate, in which the LED chip has failed.

With The advantage here is the brightness of the bulb in case of failure a LED chip as possible little impaired, and the luminance or the radiation characteristic of the signal generator or the signal light can with advantage despite the Failure of the LED chip remain virtually unchanged.

This is an advantage over a parallel connection of all LED chips of the bulb, which in one Row side by side on a support plate where are the brightness of the light from LED chips elevated can not be near the failed LED chips are arranged on the support plate. However, an increase in brightness in these areas is often not absolutely necessary and even the risk of adverse inhomogeneity in the Radiation characteristic, the brightness or the luminance of the Increase signal generator.

Furthermore, if a LED chip fails due to a short circuit, only the parallel block with respect to the light generation, which comprises the short-circuited LED chip, fails. If the number of LED chips present in the parallel blocks is kept low, the signal transmitter advantageously remains in the event of a LED chip failure due to a short circuit safe area.

One Light-generating bulb according to the present invention comprises a plurality of in a row next to each other on a support plate arranged LED chips, wherein the illuminant 55% or more of from him generated luminous flux in a coherent Solid angle range of π or total less radiates.

Under a coherent one Solid angle range here can be considered a solid angle range, which in projection on the plane of the support plate a simply connected area represents.

Prefers becomes such a light source in a signal generator, especially preferably a signal generator of the type described above and below used or is for the use provided in such a signal generator.

The Above and below described features of the bulb can be Accordingly, also to a signal generator, in particular a signal generator of the type mentioned above, and vice versa.

With Advantage can be achieved by the use of such a light source the efficiency of the signal generator can be increased. By doing that, 55% or more of the luminous flux generated by the lamp in a relatively narrow Solid angle range is emitted, this part of the luminous flux simplified downstream of the bulb optics, such as be processed the condenser of a signal generator. Furthermore is the proportion of the luminous flux generated by the lamp, the of one on a housing Absorbent material is absorbed by the signal generator compared to conventional Lamps advantageously reduced.

Of the For example, the above-mentioned solid angle range of π or less can be by a ball sector with a vertex angle of 60 ° or less correspond spanned solid angle range. Such a sphere sector may at least the above contiguous solid angle range approximately lock in. The solid angle range is then substantially through the part of the surface of the ball sector determines the part of a ball with unit radius whose center is through the vertex of the sphere sector given is.

Prefers becomes 60%, more preferably 65%, or more of the generated luminous flux in the related Solid angle range radiated. Furthermore, the corresponding to the solid angle projected vertex angles of a sphere sector preferably 55 °, especially preferably 50 ° or less. Advantageously, thereby the efficiency of the bulb or that of the signal generator can be further increased.

In a preferred embodiment of the bulb includes this an optical element, preferably the LED chips from the carrier plate is subordinate from seen. Such an optical element can Advantageously, the proportion of the luminous flux generated by the lamp, which is radiated into one of the above-mentioned solid angle ranges, increase.

The optical element comprises Furthermore, it prefers an optical functional area which is especially preferably in the manner of a lens, for example curved, formed is. The optical element may have a plurality of optical functional areas have, with advantage substantially each in the lamp existing LED chip is assigned an optical functional area, so that's a great advantage Proportion of the luminous flux generated by the LED chips on the optical Functional area meets.

This optical functional area is preferably formed so that of the LED chips from incident on the optical functional area light rays through the optical functional area partly in the manner of a converging lens and partially broken in the manner of a diverging lens. Of the optical functional area is in other words so that of Luminous element on this incident light rays partially to optical axis of the functional area and partly of the optical axis are broken off. With particular advantage can so over suitable design of the optical functional area a very homogeneous radiation characteristic of the bulb over a high angle range can be achieved. This in turn can be positive on the emission characteristic or the luminance of such a generated Signal light effect.

Especially can a such a light source downstream condenser on its side facing the bulb very homogeneous from the bulb be irradiated, what for the emission characteristics of a signal generator with such Bulbs can be beneficial.

In a preferred embodiment of the optical element, this is formed in one piece and may be connected, for example via a fastening device with the support plate. Advantageously, the optical element can thus be provided on the carrier plate in a simplified manner after the arrangement of the LED chips. The fastening device may include locking devices on the support plate and / or the optical element, which are preferably matched to each other, so that the optical element can be easily attached to the support plate.

Around the optical coupling between the LED chip and the optical Element can improve, between the LED chip and the optical Element, preferably between the LED chip and the LED chip associated functional area of the optical element, a refractive index matching material be arranged. Preferably contains such a refractive index matching material silicone which is through high resistance at high temperatures, as in the operation of the bulb may occur. The Refractive index matching material may be in various forms, for example, as a film, resin, paint, liquid, gel and / or oil. As resins For example, reactive resins such as acrylic, silicone, epoxy resins are suitable or mixtures of these resins.

Other features, advantages and advantages of the invention will become apparent from the following in connection with in the 1 . 2 and 3 described embodiments.

Show it

1 in 1A a schematic sectional view of an embodiment of a signal generator according to the invention, in 1B a plan view of a light source in a signal generator according to the invention, and in 1C a schematic representation of the luminous flux distribution of the signal generated by the signal generator signal light,

2 a schematic representation of an embodiment of a luminous means according to the invention based on a supervision in 2A , a schematic sectional view in 2 B , A schematic representation of the radiation characteristic of a luminous means according to the invention in 2C and a representation of the angle dependence of the luminous flux component in 2D and

3 in the 3A and 3B schematically two embodiments of an interconnection of the LED chips in a lamp according to the invention.

Same and similar elements are in the figures with the same Provided with reference numerals.

In the 1 is based on the 1A a schematic sectional view of an embodiment of a signal generator according to the invention, based on the 1B a plan view of a light source in a signal generator according to the invention, and with reference to the 1C a schematic representation of the luminous flux distribution of the signal generated by the signal generator signal light is shown.

The signal generator 1 has a signaler housing 2 with a sounder housing back 3 on, on which a bulb 4 is arranged. The light source 4 includes a plurality of in a row next to each other on the support plate 5 arranged LED chips 6 , Downstream of the lamp is a condenser 7 and this in turn is a scattering element 8th downstream. The signal generator is preferably designed as a retrofit, which can be fitted, for example, in a conventional traffic light system.

An inventive lamp 4 for a signal transmitter with on a support plate 5 essentially in a single-row row arranged LED chips 6 is in 1B shown. The drawn essentially rectangular coordinate system denotes H the lateral horizontal orientation of the row, whereas V denotes the vertical orientation of the carrier plate. The vertical direction is also in 1A indicated by the arrow labeled V. The horizontal direction corresponds in the 1A the direction in the plane of the drawing.

The LED chips preferably emit light in the visible spectral range during operation, most preferably they produce a total of light of a signal light color, such as one of the traffic signal colors red, yellow or green, or Mixed-color, in particular white light. The LED chips are preferably is formed so that the signal light with respect to the wavelength of the corresponding standards.

The support plate contains preferably a material with high thermal conductivity, the removal takes over the heat generated by the LED chips. Such a carrier plate is advantageous heat-conducting with the auto switch housing connected to the heat dissipation from the LED chips continue to improve. The danger of a failure the light source and thus the signal generator can thus be advantageous be reduced. Such a carrier plate preferably contains a metal and / or a ceramic.

Furthermore, the carrier plate is preferably formed as a printed circuit board, such as a metal core or ceramic board having a conductor pattern for contacting the LED chips in addition to the LED chips can also be further (micro) electronic or Optoelectronic components may be provided on the carrier plate or in the signal generator. For example, sensors that control the LED chips according to the ambient brightness, or transistors that facilitate the detection of the functional state of the lamp advantageous.

In the signal transmitter 1 in 1A generates the light source 4 in operation light beams 9 , which are bundled by the condenser in the sectional view substantially parallel and from the scattering element substantially either as radiation 9a in the direction of the signal level 10 be scattered or unchanged parallel to the optical axis 11 extend further. The signal level 10 is spaced from the bulb and can be given in the case of a traffic light system for road traffic, for example, through the street level.

The condenser 7 is for example formed on its side facing away from the light source in the manner of a step or Fresnel lens, arranged in the focus or focal area of the light source. The lens profile is preferably matched to the requirements of the signal generator.

A signal generator in the 1A shown type with the bulb 1B has several advantages. On the one hand, the production of such a signal transmitter is simplified compared with a signal transmitter of the plurality of lamps and a plurality of condensers associated therewith. The light sources and the condensers often have to be tuned to one another in a complex manner and positioned relative to one another. In particular, the condensers often have to be elaborately manufactured so precisely that they border each other in the signal generator without gaps.

at a signal generator according to the invention, however can such a high coordination or adjustment effort with advantage be avoided, since only one light source is present, the one Condenser is assigned. Thus, only a condenser and a bulb to be matched. The effort, the the vote of the lamps and the condensers and the condensers with each other requires, is thereby advantageously reduced. Furthermore, the Requirements for the tolerances that the edge area of the condenser fulfill should be lower, as in the invention, the bulb only a condenser is assigned, and the gapless adaptation next to each other arranged condensers can be avoided. Furthermore, such is Signal generator cost-effective producible, since only one light source must be provided. Moreover can be the costly and costly vote of several condensers account for several bulbs.

In the 1C is schematically the luminous flux distribution 90 of the signal emitted by the signal generator light in response to a vertical angle 99 , a viewing direction in the vertical direction with the optical axis 11 out 1A , forms. The vertex of the vertical angle is in this embodiment by the intersection of the optical axis with the scattering element 8th given in the embodiment in 1A forms the light exit surface of the signal light from the signal generator. For positive vertical angles - direction of rotation away from the optical axis counterclockwise - the luminous flux distribution has a very steep slope 91 , which among other things by the scattering element 8th is effected, which diffuses from the condenser on the scattering element incident light substantially in the direction of the signal plane. In the presentation of the 1C this corresponds to a negative vertical angle with the optical axis. The luminous flux distribution 90 has a maximum at relatively small negative angles, whereby the visibility of the signal light is facilitated even from long distances, and then decreases relatively slowly, so that the signal light can still be detected well in the vicinity of the signal generator by an observer.

Light beams generated by the luminous means are influenced by the passage through the condenser and the scattering element such that the luminous flux of the signal light radiated into the region with positive vertical angles is advantageously low. This can increase the efficiency of the signal generator. A large part of the luminous flux of the signal light is radiated so advantageous in a useful range, in the direction of the signal level 10 and is in the range of negative angles with the optical axis. A radiation of the signal light in a loss range positive vertical angle in which the signal light can not be perceived by an observer in the signal level or only difficult, at the expense of emitted in the direction of the signal plane luminous flux is largely avoided.

The horizontal one row array of LED chips 6 on the carrier plate 5 in the lamp facilitates due to their small vertical extent advantageous to the formation of the steep flank 91 in the luminous flux distribution of the signal light. In particular, this applies in comparison with a signal generator which has a plurality of such lamps, which are at a vertical distance from each other on the back 3 the signal transmitter housing are arranged. In the 1C illustrated luminous flux distribution 90 corresponds essentially to the course of a required in EN 12368 distribution, which can meet the signal generator, at least in this regard. For achieving a required radiation characteristic of the signal generator, in particular in horizontal Direction, where often high divergence of the signal light is required, a short series arrangement of eight or fewer LED chips may be advantageous.

On the signal generator 1 incident extraneous light 12 , For example, sunlight is scattered by the scattering element substantially also in the direction of the signal plane and the condenser on the inside 13 directed the signal generator housing. The inside 13 is preferably at least partially with an absorbent material 14 provided, which substantially absorbs the extraneous light. The phantom light properties of the signal generator are thereby improved with advantage. Because of the small vertical extent of the luminous means and the steep flank in the luminous flux distribution of the signal light, only a very small part of the extraneous light strikes the luminous means, whereby the phantom light properties are advantageously further improved.

The signal generator can advantageously the phantom light class 4 or 5 comply with DIN 67527-1.

The absorbent material is often provided for achieving good phantom light properties, such as the properties specified in the above-mentioned phantom light classes. For the efficiency of the signal generator, it is therefore advantageous if the highest possible proportion of the light source 4 emitted light is emitted in a solid angle range in which it is not absorbed by the absorbent material.

Preferably, therefore, the greatest possible proportion of 55% or more of the luminous flux generated by the luminous means is emitted by the luminous means into a coherent solid angle range in which the light from the luminous means is emitted in direct line, without the inside 13 of the housing, on an illuminant downstream optical element, such as the condenser 7 in the present embodiment, meets.

This solid angle range is in the sectional view in FIG 1A by way of example by the borderlines 15 limited shown, which emanate substantially from the center of a light-generating region of the LED chips, and comprises the optical axis 11 ,

The corresponding three-dimensional solid angle range has substantially the shape of the spherical partial surface of a spherical sector of a sphere of unit radius around the vertex 16 the vertex angle 17 the borderlines 15 with the optical axis 11 lock in. Light emitted by the light source into this solid angle range strikes the condenser directly and can be bundled by it and leave the signal generator via the diffuser. The vertex angle 17 is preferably 55 °, more preferably 50 °, or less. In this embodiment, the one of the boundary lines includes 15 included angle range just the condenser 7 , It is understood that this should not be regarded as a limitation to such training.

By a suitable training of the bulb, the proportion of the from the illuminant to one of the above-mentioned solid angle ranges radiated light advantageously influenced and / or further increased.

2 shows a schematic representation of an embodiment of a luminous means according to the invention by means of a plan view in 2A , a schematic sectional view in 2 B , A schematic representation of the radiation characteristic of a luminous means according to the invention in 2C and a representation of the angular dependence of the luminous flux component in 2D ,

In 2A is a plan view of an embodiment of a luminous means according to the invention shown schematically.

The LED chips 6 of the bulb 4 are in 2A in a single line row on the backing plate 6 arranged. The carrier plate is formed for example as a printed circuit board, which serves for the electrical contacting of the LED chips. The carrier plate 5 with the LED chips 6 is shown in dashed lines, as the LED chips 6 an optical element 18 is arranged downstream, which is integrally formed and the carrier plate 5 spanned in supervision. The optical element comprises a plurality of optical functional areas 19 , wherein each of, for example, six, LED chips, such a functional area 19 assigned.

The optical functional areas 19 are preferably arranged centrally above the light-generating region of the LED chips, spatially separated from each other and / or have a substantially circular outline in plan view.

In the 2 B is a section along the line AA through the in 2A shown bulbs shown schematically. The LED chip 6 is in a recess 21 a housing 20 arranged, which is formed, for example, according to a surface mountable LED design. In this embodiment, a housing is shown by way of example, which is produced by molding or Umpressen a lead frame, for example in the premold method. The LED chip is with the connections 22 and 23 for example, via egg NEN bonding wire 24 and a solder joint on the bottom of the LED chip electrically connected. In the recess is a wrapping material 25 arranged, which protects the LED chip advantageous against harmful external influences. The connections 22 and 23 are conductively connected to printed circuit boards, not shown, on the carrier plate, which is formed, for example, as a printed circuit board such as a metal core board. The wrapping material preferably contains a reaction resin, for example an acrylic, epoxy or silicone resin or a mixture of these resins.

The optical element 18 with the optical functional area arranged centrally above the LED construction 19 is connected to the support plate via a fastening device which in this example as a locking device, which is a projection 26 on the carrier plate and to this projection 26 corresponding snap hooks 27 that is the optical element 18 are formed. The projection and the latch are merely an exemplary embodiment of the fastening device. The fastening device preferably does not extend beyond the surface of the carrier plate facing away from the LED chips, so that the attachment of the carrier plate to an external heat sink, such as a signal transmitter housing, is facilitated.

The optical element 18 closes with the carrier plate 5 a gap 28 one. Between the LED construction and the optical functional area is a gap in this embodiment 280 arranged. Light generated by the LED chip leaves the LED form over the wrapping material and passes through the gap to the optical functional area 19 which is preferably designed so that the largest possible proportion of the luminous flux generated by the LED chip is radiated by the illuminant as a whole in a solid angle range, which coincides with the optical axis 11 an angle 29 of 55 ° or less. The vertex of the angle 29 is thereby by the intersection of the optical axis 11 with the light exit surface 30 of the optical element.

To the optical connection of the LED design to the optical functional area 19 to improve is in the cavity 28 , especially in the gap 280 , a refractive index matching material 31 arranged. The refractive index matching material 31 advantageously reduces the jump in the refractive index, the light generated by the LED chip on the way to the light exit surface 30 of the optical functional area 19 experiences and thus increases the functional range reaching proportion of the light generated by the LED chips. The ratio of the refractive indices of adjoining materials here is preferably less than 1.4: 1 and more preferably less than or equal to 1.4: 1.5. Here, 1.4 is a typical refractive index for a cladding material of the semiconductor chip and 1 is the refractive index of air that is in the absence of the refractive index matching material in the gap 280 can be located. Through the refractive index matching material 31 For example, the proportion of the light generated by the LED chip of the optical element via the light exit area 30 of the optical functional area 19 leaves are advantageously increased because the reflection at the interfaces by the matched refractive indices of cladding, refractive index matching material and material of the optical element can be advantageously kept low.

Preferably, the refractive index matching material comprises silicone which, at 1.5, may have a refractive index well matched to many LED chip packaging materials. The silicone can be present for example in the form of a highly crosslinked silicone gel or a silicone oil. Preferably, the refractive index matching material fills substantially the entire cavity 28 out. To reduce detrimental leakage of the refractive index matching material from the cavity, the cavity is via sealing means 32 sealed with respect to the environment of the cavity. This seal is preferably provided around the entire support plate.

Furthermore, the cavity 28 areas 281 on, which include the dots coming from the backing plate 5 have a greater distance than the points in the gap 280 are arranged. It can thereby be achieved that gas bubbles, which may have a disadvantageous refractive index, such as, for example, air bubbles, collect in regions which are relatively far away from the gap 280 are removed. The risk of a disadvantageously high refractive index jump in the area of the gap 280 can be reduced with advantage.

If liquid silicone oil is used, the cavity is advantageously very good - for example, by the left seal in 2 B - Sealed so that possible little silicone oil can escape. The risk of simultaneously penetrating air bubbles can be reduced.

In the case of silicone gel, the sealing requirements are lower because the silicone gel is highly cross-linked and, for example, via the right seal 32 sealed cavity can only be difficult to leave.

Overall, the light source is designed so that the largest possible proportion of the luminous flux generated by the LED chip in the by the angle 29 marked solid angle range is radiated. This can increase the efficiency of the bulb and in particular the efficiency of a signal generator with such a light source such as the signal generator in 1A be increased.

The optical functional area and in particular its light exit surface 30 are therefore preferably designed so that the proportion of the luminous flux generated by the LED chip, which in the solid angle range of the angle 29 is determined, emitted is as large as possible. The light exit surface is formed so that it partially incident on the LED chip light rays in the manner of a converging lens to the optical axis 11 breaks down and partially breaks away in the manner of a diverging lens from the optical axis.

Deviating from the illustration in 2 B The optical element can also be directly adjacent to the LED chip or the LED design. Preferably, an optical functional area can be formed in a directly on the LED chip or the LED design. For this purpose, for example, a film, such as a silicone film, arranged over the LED chip. The lens profile can be formed in the film, for example by stamping, or already formed.

In the 2C is schematically illustrated the radiation characteristic of a luminous means according to the invention with such an optical element polar. The angle labeled 90 ° corresponds to the optical axis 11 in 2 B ,

The majority of the intensity generated by the light source is radiated in an angular range of 55 ° with respect to this optical axis. Furthermore, the radiation characteristic over the angular range in the 2C from about 140 ° to 40 ° very homogeneous and substantially rotationally symmetrical to the optical axis and has no minimum in particular in the region of the optical axis. The originally Lambertian cosine-shaped characteristic of the LED design or of the LED chip is determined by the optical element as shown in FIG 2C shaped.

In 2D is shown schematically the dependence of the luminous flux component in percent of the angle to the optical axis for a lighting device according to the invention. More than 85% of the luminous flux emitted by the lamp is radiated in an advantageously narrow solid angle range, which forms an angle of 50 ° with the optical axis. At angles of just over 50 °, almost 90% of the luminous flux generated by the luminous means is radiated into the solid angle range corresponding to 50 °.

In the 3 are based on the 3A and 3B schematically illustrated two embodiments of an interconnection of the LED chips in a lamp according to the invention.

The LED chips 6 of the bulb 4 , which are in the form of, for example, surface-mountable LED designs, are in 3A schematically with reference to their switching symbols as substantially in a horizontal single-row row on the support plate 5 arranged shown.

The example, six LED chips are with the contact terminals 34 and 35 , which have different polarity, via the conductor tracks 35 electrically conductive, for example via a solder joint, connected. The carrier plate is preferably formed as a printed circuit board, which preferably has a high thermal conductivity, such as a metal core or a ceramic board. This allows a good thermal connection of the LED chips to a heat sink, such as the housing of a signal generator can be achieved.

At the Failure of an LED chip with an open-contact does not flow More electricity, so that the bulb no longer generates light and remains in a reliable area.

In the 3B is another embodiment of an interconnection of the LED chips 6 on the carrier plate 5 of the bulb 4 shown schematically. The LED chips 6 are in parallel blocks 36 connected in parallel. In 3B By way of example, in each case 2 LED chips are connected in parallel and three such parallel blocks are connected in series. The parallel blocks can be connected via the contact connections 33 and 34 and the tracks 35 on the carrier or circuit board 5 be electrically connected. In the area of serial connections between the parallel blocks 36 Advantageously, no LED chips are arranged, whereby the risk of a total failure of the bulb is avoided in the event of failure of such a serially connected between two parallel blocks LED chip with open-contact. The LED chips connected in parallel in the parallel blocks are preferably in the horizontal single-row arrangement of the LED chips 6 on the carrier plate 5 , as in 3B shown as possible arranged side by side.

Come in mind LED chip with open-contact off, so will the current through the too the failed LED chip parallel LED chip flows increased. This goes with an increase in brightness of the generated by this LED chip Light comes along. The brightness increase takes place through the juxtaposition the parallel-connected LED chips preferably in the areas of support plate instead, in which the LED chip has failed.

By such an interconnection of LED chips on the carrier plate as in 3 illustrated, it can be achieved with advantage that a signal generator with such a light source, in particular a signal generator with light sources having such an interconnection of the failure of an LED chip within a reliable range remains. The radiation characteristic of the signal emitted from the signal generator from light changes with advantage in case of failure of an LED chip with open-contact or only to a very small extent, as in 3B , or the signal light turns off at open-contact completely, as in 3A ,

Of the Whereabouts of the illuminant or the signal generator within one reliable area can thus advantageously by the interconnection the LED chips on the carrier plate be achieved and it must not LED chips on different carrier plates or different Illuminants are interconnected to achieve this. The effort for the production of such lamps and in particular such Signal generator can be reduced with advantage. With particular advantage can carrier plates already prefabricated with different wiring options, where not needed Interruptions in the interconnect structures on the carrier plates through bridges, like for example, so-called 0-ohms Resistors, to be bypassed can.

It It should be noted that instead of LED chips in the context of the invention, each other suitable light source can be provided, so that other light sources to be covered by the invention. Furthermore, the term light as a synonym for electromagnetic radiation, especially in the visible, ultraviolet or infrared spectral range used.

Claims (21)

Signal transmitter with a light ( 9 ) generating bulbs ( 4 ), a plurality of in a row next to each other on a support plate ( 5 ) arranged light-emitting elements ( 6 ), the signal transmitter ( 1 ) exactly such a light source ( 4 ) characterized in that the lighting means ( 4 ) LED chips as light-emitting elements and an optical element ( 18 ), which the LED chips ( 6 ) from the carrier plate ( 5 ) is arranged downstream of and on the support plate ( 5 ) is attached. Signaling device according to claim 1, characterized in that the arrangement of the LED chips ( 6 ) on the support plate line-like, preferably one-line, is. Signaling device according to claim 1 or 2, characterized in that the lighting means ( 4 ) eight, preferably six, or fewer LED chips ( 6 ) Includes. Signaling device according to one of the preceding claims, characterized in that the lighting means ( 4 ) a condenser ( 7 ) downstream of the light source ( 4 ) generated light beams ( 9 ), which on the condenser ( 7 ), bundles. Signaling device according to claim 4, characterized in that the signal transmitter ( 1 ) exactly one condenser ( 7 ). Signaling device according to claim 4 or 5, characterized in that the condenser ( 7 ) from the light source ( 4 ) seen from a scattering element ( 8th ), which is that of the condenser ( 7 ) out onto the scattering element ( 8th ) incident light rays ( 9 ) in the direction of a signal level ( 10 ) scatters. Signaling device according to claim 6, characterized in that the scattering element ( 8th ) Extraneous light ( 12 ), that of the bulb ( 4 ) meets the scattering element on the opposite side, such that the proportion of extraneous light ( 12 ), which on the light source ( 4 ), compared with a signal generator ( 1 ) without scattering element ( 9 ), is reduced. Signaling device according to claim 7, characterized in that the extraneous light ( 12 ) at least partially on an absorbent material ( 14 ) and is at least partially absorbed by it. Signaling device according to one of the preceding claims, characterized in that the signal transmitter ( 1 ) is intended for a traffic light system. Signaling device according to one of the preceding claims, characterized in that the signal transmitter ( 1 ) complies with EN 12368 or DIN 67527-1. Signaling device according to one of the preceding claims, characterized in that the signal transmitter ( 1 ) meets phantom class 4 or 5 according to EN 12368 or DIN 67527-1. Signaling device according to one of the preceding claims, characterized in that the LED chips ( 6 ) are connected at least partially in series. Signaling device according to one of the preceding claims, characterized in that the LED chips ( 6 ) are connected at least partially in parallel. Signaling device according to one of the preceding claims, characterized in that at least two LED chips ( 6 ), which are connected in parallel to each other, adjacent to each other on the carrier plate ( 5 ) are arranged. Light-generating illuminant ( 4 ), which has a plurality of LED chips arranged in a row next to one another on a carrier plate ( 6 ), characterized in that the lighting means ( 4 ) an optical element ( 18 ), the LED chips ( 6 ) from the carrier plate ( 5 ) and that the optical element ( 18 ) on the carrier plate ( 5 ) is attached. Illuminant according to claim 15, characterized in that the optical element ( 18 ) is integrally formed. Illuminant according to one of claims 15 or 16, characterized in that substantially each in the lamp ( 4 ) existing LED chip ( 6 ) an optical functional area encompassed by the optical element ( 19 ) assigned. Illuminant according to one of claims 15 to 17, characterized in that the optical element ( 18 ) a plurality of optical functional areas ( 19 ). Illuminant according to claim 17 or 18, characterized in that the optical functional area ( 19 ) is formed in the manner of a lens. Illuminant according to one of claims 15 to 19, characterized in that between the carrier plate, in particular the LED chip, and the optical element, preferably a silicone containing, refractive index matching material is arranged. Illuminant according to one of Claims 15 to 20, characterized in that the illuminant ( 4 ) for a signal generator ( 1 ) is provided according to one of claims 1 to 14.