The invention relates to a lighting apparatus and a lighting method.
EP 1 898 144 A2 discloses a lighting apparatus comprising several light emitting diodes which are connected with and distributed over a heatsink. The several light emitting diodes generate several light beams which are generally differently blocked, if an obstruction is present in the light paths of the several light beams. This different blocking for different light beams leads to selective shadowing effects.
It is an object of the present invention to provide a lighting apparatus comprising several light sources, wherein selective shadowing effects can be reduced. It is a further object of the present invention to provide a corresponding lighting method. In a first object of the present invention a lighting apparatus is presented, wherein the lighting apparatus comprises:
a first light device comprising a first light source for generating a first light beam and a light emanating element from which the first light beam emanates,
a second light device comprising a second light source for generating a second light beam,
wherein the first light device and the second light device are arranged to direct the second light beam to the light emanating element of the first light device, wherein the light emanating element is adapted to redirect the second light beam such that the redirected second light beam emanates from the light emanating element.
Selective shadowing effects in an illumination pattern generated by two light sources are more likely, if the two light sources are arranged at different locations as it is generally the case. Since the first light device and the second light device are arranged to direct the second light beam to the light emanating element of the first light device, wherein the light emanating element is adapted to redirect the second light beam such that the redirected second light beam emanates from the light emanating element, and since also the first light beam emanates from the light emanating element, both light beams appear to originate from the same light emanating element, i.e. from the same location. The probability of generating selective shadowing effects can therefore be reduced, in particular, selective shadowing effects can be eliminated.
The light emanating element can be a part of the first light source, for example, an outer part, in particular, an outer surface, of the first light source, through which the first light beam leaves the first light source, wherein this outer part, in particular, the outer surface, of the first light source is preferentially reflective for redirecting the second light beam. The light emanating element can also be integrated into this outer part, for example, by embossing and/or imprinting. However, the light emanating element can also be a part being separate from the first light source, for example, the light emanating element can be located on the outer part of the first light source, through which the first light beam leaves the first light source and which may or may not be reflective to the second light beam. The second light beam can be oriented perpendicular, parallel or transverse to an outer surface of the first light source, through which the first light beam leaves the first light device.
The redirection of the second light beam by the light emanating element includes any direction change which can be induced by the light emanating element. For example, the light emanating element can redirect the second light beam, i.e. induce a direction change of the second light beam, by reflection, diffusion, refraction, diffraction, converting the second light beam into another kind of light with a propagation direction being different to the propagation direction of the second light beam, et cetera.
The first light beam and the redirected second light beam emanate from the light emanating element. This does not mean that the first light beam and the redirected second light beam have to be generated in the light emanating element, but it means that the first light beam and the second light beam both come from the light emanating element. For example, the first light beam can traverse the light emanating element, wherein after having traversed the light emanating element the first light beam comes from the light emanating element, and the second light beam can be redirected, in particular, reflected, by the light emanating element, wherein after having been redirected by the light emanating element also the redirected second light beam comes from the light emanating element.
The lighting apparatus is preferentially adapted to be used in decorative lighting, shop lighting and atmosphere creation. The lighting apparatus may be a retrofit lamp, which might be used in, for example, torches, toys and/or luminaires.
The first light device and the second light device provide preferentially different kinds of light. The lighting apparatus is therefore preferentially a hybrid lighting apparatus.
It is preferred that the first light source is a light emitting diode and the second light source is a laser. The laser is preferentially a laser diode. This allows the lighting apparatus to generate, for example, a high intensity laser illumination on a background illumination generated by the light emitting diode.
The light emanating element can be adapted to redirect the second light beam by reflecting the second light beam such that the reflected second light beam emanates from the light emanating element. In particular, as already mentioned above, the light emanating element can at least partly be formed by an outer surface of the first light source through which the first light beam leaves the first light source, wherein this outer surface can be reflective to the second light beam for redirecting the same.
The light emanating element can have any size. For example, it can cover a complete outer part of the first light source through which the first light beam leaves the first light source, it can cover only a part of this outer part or it can be larger than this outer part, i.e. it can protrude over the edges of this outer part. The light emanating element may also have any thickness. Moreover, the light emanating element has a surface met by the second light beam, which can have any surface structure, i.e. this surface may have a flat surface, a rough surface or comprise another desired shape.
It is further preferred that the light emanating element is adapted to redirect the second light beam by reflecting the second light beam for generating a reflection pattern. This allows the lighting apparatus to generate a desired illumination pattern with reduced or without selective shadowing effects. The reflection pattern can be a speckle pattern or can comprise light spots. Also the reflection pattern can be superimposed on the illumination generated by the first light beam for generating a combined illumination pattern.
It is further preferred that the light emanating element is adapted to redirect the second light beam by diffusing the second light beam for generating a speckle pattern. The speckle pattern can be superimposed on the illumination generated by the first light beam for generating a combined illumination pattern. The diffusing element can be adapted to produce a sparkling speckle pattern.
It is further preferred that the light emanating element is adapted to redirect the second light beam by diffracting the second light beam for generating a diffraction pattern. Also the diffraction pattern can be superimposed on the illumination generated by the first light beam for generating a combined illumination pattern. The light emanating element can be adapted to generate a desired diffraction pattern with reduced or without selective shadowing effects.
It is further preferred that the light emanating element is adapted to redirect the second light beam by converting the second light beam into a third light beam having a color being different to the color of the second light beam, wherein the third light beam emanates from the light emanating element. For example, a phosphor element comprised by the light emanating element can be used for converting the wavelengths of the second light beam. This can be used to generate advanced colored effects.
It is further preferred that the second light device is adapted to generate several second light beams for being directed to the light emanating element, wherein the light emanating element is adapted to redirect the several second light beams such that the redirected several second light beams emanate from the light emanating element. The second light device can comprise one or several beam splitters and/or several second light sources like several lasers for generating several second light beams. This allows the lighting apparatus to generate an illumination pattern by overlapping several illumination patterns generated by the different light beams with a reduced probability of selective shadowing effects, in particular, without any selective shadowing effects.
It is further preferred that the first light device comprises multiple light emanating elements, wherein the first light device and the second light device are arranged to allow the first light beam to traverse the multiple light emanating elements and to allow the second light beam to be redirected by the multiple light emanating elements. This allows the lighting apparatus to redirect the second light beam by the multiple light emanating elements which can influence the second light beam differently. For example, different light emanating elements can influence the second light beam differently, wherein these different influences can generate a certain desired illumination pattern with a reduced probability of selective shadowing effects, in particular, with no selective shadowing effects at all.
The multiple light emanating elements can form a stack on an outer part of the first light source, in particular, on an outer surface of the first light source, through which the first light beam leaves the first light source, such that first light beam traverses the stack, i.e. the multiple light emanating elements. The multiple light emanating elements are preferentially partly transparent to the second light beam such that by illuminating the stack of the multiple light emanating elements, the second light beam can enter the multiple light emanating elements for allowing the multiple light emanating elements to influence the second light beam.
It is further preferred that the first light device comprises multiple light emanating elements, wherein the first light device and the second light device are adapted to allow the first light beam to traverse the multiple light emanating elements and to allow the second light beam to be selectively directed to one or several of the multiple light emanating elements. The multiple light emanating elements can be arranged side-by-side on an outer part of the first light source, in particular, on an outer surface of the first light source, through which the first light beam leaves the first light source, such that first light beam traverses the multiple light emanating elements. The multiple light emanating elements can be adapted to redirect the second light beam differently. This allows the lighting apparatus to modify the kind of redirecting the second light beam and, thus, to modify a light pattern generated by the influenced second light beam. For example, the color and/or the spatial distribution of an illumination pattern generated by the second light beam can be modified. For allowing the second light beam to be selectively directed to one or several of the multiple light emanating elements, the second light device can comprise a redirection element, which is not the light emanating element and which is adapted to selectively direct the second light beam to the one or several of the multiple light emanating elements. In addition or alternatively, the first light device can be adapted to move the one or several of the multiple light emanating elements with respect to the second light beam such that the second light beam is selectively directable to the one or several of the multiple light emanating elements.
It is further preferred that the lighting apparatus comprises a switch for switching at least one of the first light device and the second light device. The lighting apparatus may comprise a single switch for both, the first light device and the second light device, or the lighting apparatus may comprise for each of the first light device and the second light device a single switch.
In a further aspect of the present invention a lighting method is presented, wherein the lighting method comprises:
generating a first light beam by a first light source of a first light device comprising a light emanating element from which the first light beam emanates,
generating a second light beam by a second light source of a second light device,
directing the second light beam to the light emanating element of the first light device, wherein the light emanating element redirects the second light beam such that the redirected second light beam emanates from the light emanating element.
It shall be understood that the lighting apparatus of claim 1 and the lighting method of claim 14 have similar and/or identical preferred embodiments as defined in the dependent claims.
It shall be understood that a preferred embodiment of the invention can also be any combination of the dependent claims with the respective independent claim.
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.
In the following drawings:
The light emanating element 6 is a part being separate from the first light source 2. The light emanating element 6 is located on an outer surface of the first light source 2, through which the first light beam 3 leaves the first light source 2. However, in another embodiment the light emanating element can also be a part of the first light source, for example, an outer part, in particular, an outer surface, of the first light source, through which the first light beam leaves the first light source, wherein this outer part, in particular, this outer surface, can be reflective for redirecting the second light beam. Further elements can be integrated into this outer part, in particular, into this outer surface, for further influencing the second light beam, for example, for diffusing, refracting, diffracting, et cetera, the second light beam. This integration can be performed by, for example, embossing and/or imprinting.
The first light source 2 is preferentially a light emitting diode and the second light source 4 is preferentially a laser. The first light device 52 further comprises a heatsink 8 for dissipating the heat generated by the first light source 2. The heatsink 8 is in thermal contact with the first light source, in order to allow the heatsink to dissipate the heat. The thermal contact can be achieved by directly contacting the first light source 2 and the heatsink 8, or by arranging the heatsink 8 and the first light source 2 such that the heat can radially be dissipated.
The outer part of the first light source 2 comprises an outer surface 55 through which the first light beam 3 leaves the first light source 2. The second light beam 5 can be oriented in different directions relative to this outer surface 55 as schematically and exemplarily illustrated in
The light emanating element can be provided on the first light source with a gap between the first light source and the light emanating element or without such a gap.
The second light device can be adapted to generate several second light beams for being directed to the light emanating element 6, wherein the light emanating element 6 is adapted to redirect the several second light beams such that the redirected several second light beams emanate from the light emanating element 6. The second light device can comprise one or several beam splitters and/or several second light sources like several lasers for generating several second light beams. The several second light beams can be directed to the light emanating element 6 in different directions as schematically and exemplarily shown in
Although in
Although in
The light emanating element 6 can be adapted to redirect the second light beam in different ways such that the redirected second light beam 7 emanates from the light emanating element 6. For example, the light emanating element 6 can be adapted to redirect the second light beam 5 by reflecting the second light beam 5 such that the reflected second light beam 7 emanates from the light emanating element 6. The light emanating element 6 can be adapted to generate a reflection pattern by reflecting the second light beam 5, wherein this reflection pattern is, for example, a speckle pattern or can comprise light spots. The reflection pattern can be superimposed on illumination generated by the first light beam 3 for generating a combined illumination pattern. In addition or alternatively, the light emanating element can also be adapted to redirect the second light beam 5 by diffusing the second light beam 5 for generating a speckle pattern. Also this speckle pattern can be superimposed on the illumination generated by the first light beam 3 for generating a combined illumination pattern. Moreover, also in addition or alternatively, the light emanating element 6 can be adapted to redirect the second light beam 5 by diffracting the second light beam 5 for generating a diffraction pattern. Also this diffraction pattern can be superimposed on the illumination generated by the first light beam 3 for generating a combined illumination pattern. For example, a diffractive structure can be provided on the outer surface 56 of the light emanating element 6 met by the second light beam 5.
In an embodiment, the light emanating element is formed by an outer surface of the first light source, which is reflected for redirecting the second light beam such that it emanates from this outer surface. On this outer surface one or several optical elements can be provided for influencing the reflected second light beam such that a desired illumination pattern is generated. For example, this at least one optical element can be adapted to generate a desired illumination pattern by diffraction, diffusion, refraction, et cetera. This at least one optical element is preferentially located on the outer surface 55 of the first light source like the light emanating element 6 described above with reference to, for example,
Instead of using only a single light emanating element 6 as schematically and exemplarily shown in
The different light emanating elements are preferentially adapted to influence the second light beam differently and the lighting apparatus is preferentially adapted to allow the second light beam to selectively be directed to a first light emanating element only, a second light emanating element only, or certain parts of both light emanating elements. This allows the lighting apparatus to modify the illumination pattern by modifying the illumination of the multiple light emanating elements by the second light beam. Such a kind of varying lighting effects is exemplarily and schematically also illustrated in
The second light device 253 can comprise a redirection element 260 not being the one or several light emanating elements 206, 245 as schematically and exemplarily shown in
For selectively directing the second light beam 205 to the one or several of the multiple light emanating elements 206, 245, in addition or alternatively, the one or several light emanating elements 206, 245 can be moved as schematically and exemplarily shown in
The light emanating element can also be structured. This is schematically and exemplarily shown in
The transparent covers 40, 45 shown in
In
In
The lighting apparatus 101 shown in
In
The lighting apparatus 101 preferentially comprises an input unit like a button being connected to the switching circuit 142 for allowing the user to switch the first light source and the second light source selectively on and off.
The lighting apparatus 101 further comprises an electrical contact 143 for electrically connecting the lighting apparatus to a power source of, for example, a torch, a toy or a luminaire. Also the outer part of the casing 160 is preferentially adapted to electrically contact a power source for powering the lighting apparatus.
In all of the above described embodiments the light emanating element is preferentially adapted to allow the first light beam to traverse the light emanating element such that the first light beam, which has traversed the light emanating element, and the redirected second light beam, appear to originate from the same light emanating element, i.e. from the same location.
Although in the above described embodiments, which have been described with reference to the figures, a light emanating element is located on an outer surface of the first light source, through which the first light beam leaves the first light source, wherein this light emanating element redirects the second light beam such that the first light beam and the second light beam appear to originate from the same light emanating element, is also possible that the light emanating element is integrated in the first light source. For example, the outer surface of the first light source, through which the first light beam leaves the first light source, can be reflective to the second light beam such that this outer surface is an integrated light emanating element, because the first light beam traverses this outer surface and the second light beam is reflected by this outer surface such that the first light beam and the reflected second light beam appear to originate from the same light emanating element being the outer surface of the first light source. In this case, further optical elements, which can be provided in the optical path of the reflected second laser beam, do not have to redirect the reflected second light beam. However, these optical elements can also influence the reflected second light beam, for example, by diffraction, refraction, diffusion, et cetera, while traversing the optical elements, for generating desired illumination patterns like the illumination patterns exemplarily and schematically shown in
In the following a lighting method will exemplarily described with reference to a flowchart shown in
In step S1, a first light beam 3 is generated by the first light source 2 of the first light device 52, wherein the first light device 52 comprises the light emanating element 6 from which the first light beam 3 emanates. In step S2, a second light beam 5 is generated by the second light source 4 of the second light device 53, and in step S3 the second light beam 5 is directed to the light emanating element 6 of the first light device 52, wherein the light emanating element 6 redirects the second light beam 5 such that the redirected second light beam 7 emanates from the light emanating element 6.
It should be noted that the sequence of steps S1 to S3 can be modified, in particular, these steps can be performed simultaneously. For example, the first light beam can be generated before the second light beam is generated, the second light beam can be generated before the first light beam is generated and both, the first light beam and the second light beam, can be generated simultaneously. Moreover, after the second light beam has been generated, the generation of the second light beam can continue and at the same time the second light beam is directed to the light emanating element.
The lighting apparatus is preferentially adapted to be used in decorative lighting, shop-lighting and atmosphere creation.
The light emanating element can comprise a phosphor for converting the first light beam and the second light beam or the redirected second light beam into phosphor light. The first light beam is preferentially a beam of a light emitting diode and the second light beam is preferentially a beam of a laser. The laser and the light emitting diode are preferentially pulse-width modulated for controlling the color of the lighting apparatus comprising the phosphor. Preferentially, the laser and the light emitting diode emit light in different parts of the spectrum, wherein both, the light of the laser and the light of the light emitting diode, can be converted by the phosphor. The light emanating element can be comprised of two phosphor layers arranged like the layers 6 and 26 shown in
The light emanating element can be an electrically switchable element, for example, a polymer dispersed liquid crystal (PDLC) element, a cholesteric liquid crystal element, a liquid crystal gel element, a gradient index liquid crystal element, an electro-phoretic element, or an electro-wetting element. Such an electrically switchable element may also comprise a light conversion component such as a luminescent material. By switching this light emanating element the magnitude of color conversion may be adjusted. In the same way the characteristics of the beams like the direction and/or collimation may be controlled.
Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.
In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality.
A single unit or device may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.
The control of the lighting apparatus in accordance with the lighting method can be implemented as program code means of a computer program and/or as dedicated hardware.
A computer program may be stored/distributed on a suitable medium, such as an optical storage medium or a solid-state medium, supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems.
Any reference signs in the claims should not be construed as limiting the scope.
The invention relates to a lighting apparatus. A first light device comprises a first light source for generating a first light beam and a light emanating element from which the first light beam emanates. A second light device with a second light source generates a second light beam being directed to the light emanating element of the first light device, wherein the light emanating element is adapted to redirect the second light beam such that the redirected second light beam emanates from the light emanating element. Since the first light beam and the redirected second light beam emanate from the light emanating element, both light beams appear to originate from the same location. The probability of generating selective shadowing effects can therefore be reduced, in particular, selective shadowing effects can be eliminated.
Number | Date | Country | Kind |
---|---|---|---|
10155003.6 | Mar 2010 | EP | regional |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/IB2011/050484 | 2/4/2011 | WO | 00 | 8/27/2012 |