Light Signal

Abstract

A light signal, in particular for rail-bound traffic routes, includes a light source, an optical system and a control device for adjusting an emission characteristic. In order to improve the way optical parameters, in particular regarding brightness, phantom light and path geometry can be adjusted, the control device is configured to adjust the transmission properties of at least one smart glass element disposed in the luminous or light flux.

Claims

1-10. (canceled)

11. A light signal usable for rail-bound traffic routes, the light signal comprising: a light source having an emission characteristic and emitting light flux; an optical system downstream of said light source; at least one smart glass element disposed in the light flux; and a control device configured for adjusting the emission characteristic of said light source and configured for transmission adjustment of said at least one smart glass element.

12. The light signal according to claim 11, wherein said at least one smart glass element is provided for brightness adjustment and is disposed in a region of a light output opening.

13. The light signal according to claim 11, wherein said at least one smart glass element includes a plurality of separate transmission-adjustable smart glass panels.

14. The light signal according to claim 11, which further comprises at least one ambient light sensor, said control device having a signal input side connected to said at least one ambient light sensor.

15. The light signal according to claim 11, which further comprises: at least one extraneous light sensor; said control device having a signal input side connected to said at least one extraneous light sensor to measure phantom light; and said control device having a control output side connected to said at least one smart glass element.

16. The light signal according to claim 11, wherein said at least one smart glass element is disposed in an aperture segment of the light flux between said light source and said optical system.

17. The light signal according to claim 16, wherein said at least one smart glass element includes a plurality of separate transmission-adjustable circular-segment shaped smart glass panel segments.

18. The light signal according to claim 11, wherein said at least one smart glass element protrudes into the light flux.

19. The light signal according to claim 18, wherein said at least one smart glass element protrudes into a part of the light flux.

20. The light signal according to claim 11, wherein said at least one smart glass element includes a plurality of smart glass elements protruding over different distances into the light flux.

Description

[0018] The invention will now be described in greater detail by reference to the illustrations in the figures. In the drawings:

[0019] FIG. 1 is a schematic representation of the light signal of known construction, described above, and

[0020] FIGS. 2-4 are three exemplary embodiments of light signals of known construction in the same manner of representation as FIG. 1.

[0021] FIG. 2 shows a light signal in which in place of the front panel (6, FIG. 1), a smart glass element (9) is provided. The transmittance of the smart glass element 9 and thus the brightness of the light signal is adjusted with the control device 7. The usual brightness adjustability of the light source 2 according to FIG. 1 is therefore dispensable. In the exemplary embodiment, the smart glass element 9 consists of two separate transmission controllable smart glass panels 10 and 11. By this means, the switchover between day and night operation is simplified. Furthermore, a blink function can also be realized through alternating control of the smart glass panels 10 and 11 when the desired blink frequency is not implementable due to too high a switching time of a single smart glass panel 10 or 11.

[0022] FIG. 3 shows a light signal with phantom light reduction. In place of the front panel (6, FIG. 1), a smart glass element 9, the transmission of which is adjustable by means of the control device 7 dependent upon measurement values of an extraneous light sensor 12, serves this purpose. In order to compensate for the increasing graying-out of the smart glass element 9 with relatively strong phantom effect, the control device 7 simultaneously increases the light intensity of the LED light source 2.

[0023] The exemplary embodiment represented in FIG. 4 shows a combination of the brightness regulation according to FIG. 2 with the smart glass element 9 and the phantom light reduction according to FIG. 3 with the smart glass element 9 and a further smart glass element 9 for light flux deflection relative to the optical axis. It is evident that the smart glass element 9 is arranged between the LED light source 2 and the optical system 3. In the exemplary embodiment, the smart glass element 9 consists of two separate smart glass panel segments 13 and 14, which protrude differently far into the light flux. Apart from the control signals for the smart glass elements 9 and 9, the control device 7 also generates the control signals for the transmittance of the smart glass panel segments 13 and 14. The latter control signals can certainly be different in order to adjust the desired spatial light distribution, in particular depending on the respective track geometry.