DE9010135U1 - Receiver for optical signals - Google Patents

Description

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Siemens AG

Receiving device for optical signals 5

The invention relates to a receiving device according to the preamble of claim 1.

In known receiving devices, the limited detection efficiency of the detector results in a one-sided reception characteristic that essentially corresponds to the angle of coverage of the detector. For applications where all-round reception is necessary, an additional detector or receiving device has been used up to now . However, there are applications in which the housing of the receiving device itself is set back behind a wall or at most protrudes with part of the wall. Additional detectors would not ensure any improvement in all-round sensitivity in this application.

For applications where the receiver is built in, the additional detector would have to be arranged outside the receiver and electrically connected to the receiver via cables.

The object of the invention is to improve the receiving device so that the reception range is increased even with a built-in receiving device without the need to use additional external detectors.

The inventive solution to this problem is characterized in claim 1:

The invention is explained in more detail using two figures and a list of reference symbols/terms. 35

Figure 1 shows, partly in section, a receiving device 1 with a housing 2. On a circuit board 3

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In addition to several components that are not visible in this illustration, three detectors 4 and a holder 5 for an optical fiber 6 are attached. Light signals reach the detectors 4 via a light-permeable area of the housing 2.

The optical fiber 6 is flexible and - as shown in the drawing by the interruptions - the length of the optical fiber 6 can vary depending on the application. This allows easy installation of the optical fiber even in unfavourable space conditions.

At the first end 61 of the optical waveguide 6 there is a reception surface 7. At the second end 62 of the optical waveguide there is an end piece 8. In the example shown here, the end piece 8 is partially pushed over the end 62 of the optical waveguide 6. Light signals to be detected enter the optical waveguide 6 via the reception surface 7 and are deflected by the end piece 8 in the direction of the detectors 4.

The end piece 8 has a reflective surface from which the light rays are redirected to the detectors 4. The end piece 8 is made of a translucent solid material with a beveled outer surface. Due to the refractive index of this solid material, a Total reflection. The end 61 of the optical waveguide 6 with the receiving surface 7 is surrounded by a fastening part 10. The fastening part 10 enables the optical waveguide 6 to be securely installed in a wall 11. The wall 11 is a wall located outside the housing 2 and can, for example, When installed in a motor vehicle, the surface of the dashboard board, the roof liner or the back of the vehicle’s interior mirror. The flexible design of the optical waveguide 6 allows light coming from a different direction than the light passing through the translucent area of the housing 2 falls on the detectors 4. The reception range is thereby extended.

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As Figure 2 shows, the receiving device 1 can be installed in the headliner 12 in such a way that the translucent area 21 points in the direction of the passenger compartment and the receiving surface 7 is arranged elsewhere in the headliner 12 in the direction of the front of the vehicle. This means that signals which are emitted from the rear or sides of the vehicle in the direction of the vehicle interior and signals which are emitted from the front of the vehicle are recorded.

Figure 2 shows the reception characteristics for the receiver device according to the invention. The receiver device is installed in the roof 12 of the motor vehicle 13 in such a way that the translucent area 21 of the housing 2 points towards the interior of the vehicle. The rear reception area is marked with reference number 14.

The rear reception area 14 is essentially semicircular, only the door posts and the rear roof pillars provide shading. The first end 61 of the optical waveguide 6 is mounted in the ceiling 12 so that the reception surface 7 points in the direction of travel. This covers the front reception area 15. The front reception area 15 is also essentially semicircular, but here too the front roof pillars cause shading.

Claims (4)

G1375DE Protection claims 1. Receiver for optical signals with - at least one detector (A) which has a limited detection angle for optical signals and - a housing (2) accommodating the detector (λ) and at least partially permeable to optical signals characterized in that at least one light-guiding element (6) is provided, - whose first end (61) is designed to feed in optical signals and receives optical signals from a direction outside the detection angle, and - whose second end (62) ends in the housing (2) of the receiver and is arranged in the device in such a way that the first end (61) fed optical signals reach the detector (4). 2. Receiving device for optical signals according to Al, characterized in that at the second end (62) of the light guide element (6) a device is arranged which deflects optical radiation emerging axially from the light guide element (6) to the detector (A). 3. Receiving device for optical signals according to A1 or A2, characterized in that the device contains an inclined reflecting surface (9)» 4. Receiving device for optical signals according to A1 or A2, characterized in that the light-guiding element (6) consists of a bundle of individual optical waveguides (6).