DE102010043295A1 - Light emitter module - Google Patents

Abstract

The present invention relates to interior lighting, in particular by means of LEDs, such as those used in automobiles. Such lighting can be so-called ambient lighting or effect lighting, but also signal lighting (for example in the event of danger). The light emitter module according to the invention comprises: an LED (5) and a sensor (2), the LED (5) and the sensor (2) being connected via a control unit, an optical fiber that can be inserted into the module and is opposite the LED (5) ( 4A-B), and a housing (G) in which the LED (5) and the sensor (2) are accommodated, the sensor (2) being arranged in such a way that it passes from the LED (5) into the light guide (4A) coupled in and can again detect a light coupled out of the light guide (4B).

Description

1. Technical area

The present invention relates to interior lighting, in particular by means of LEDs, as used for example in automobiles. Such lighting can be a so-called ambient lighting or effect lighting, but also a signal lighting (eg. In case of danger).

2. State of the art

In the field of ambient lighting for vehicles, in addition to already known monochromatic lighting, there is a desire for multicolor. In-house, it is known to implement such multicolor with multiple single-color LEDs. However, the available space is small, which is why the coupled to the LEDs light guide should not exceed a certain diameter. Since the light pipe is to be ensured further homogeneous over long lengths, it is usually assumed that a maximum light pipe diameter of 5.5 mm. With such a diameter, however, one can couple light by means of a maximum of two monochromatic LEDs.

By mixing the intensity of these two LEDs, in addition to a specific color of an LED, additional mixed colors can be generated, which lie in the CIE standard table on connecting lines between the pure colors.

In order to be able to further increase the variety of colors in the vehicle, and even to be able to provide an unlimited number of colors, it would be advantageous to use one RGB LED instead of several single-color LEDs. When using such an RGB LED could also be used light guide with a diameter of 3.5 mm.

A color sensor could be used to control the RGB LED. However, the problem arises that the light emitted by the RGB LED light must be thoroughly mixed before it reaches the color sensor. A direct irradiation in the color sensor is not possible because the intensity and color coordinates are falsified.

As prior art is the document DE 10 2006 099 551 B4 known, which relates to a device for generating light of a freely selectable color with a plurality of single-color bulbs. A controller is designed here as a microprocessor and connected by means of a line with a temperature sensor for detecting the temperature of the LEDs. Likewise, the controller is connected by means of a line with a photodiode, which is arranged facing a light exit surface of a prism whose light entrance surface faces the photodiodes.

Another prior art is the document DE 10 2008 039 364 A1 known, which relates to a semiconductor light-emitting device. The semiconductor light source may include at least one LED. Furthermore, there may be a plurality of same-colored and / or different-colored light-emitting diodes.

Another prior art that DE 10 2008 025 865 A1 relates to a method for operating an LED module consisting of a number of different colored LEDs. From this prior art, the problem already arises that in the case of the new procurement of an RGB-RGBA or hybrid LED module, only the reproducibility of defined LED light will enable the use of LED technology in general lighting. Only a color sensor, which determines the color location and thus can calculate the individual color components, allows accurate color control.

3. Subject of the invention

The object of the present invention is to provide a module with an LED and a sensor, in which the components can be accommodated in a small installation space, and at the same time the light emitted by the LED is hardly attenuated by the measurement with the sensor.

To achieve this object according to the invention, a module according to claim 1 is provided. Exemplary embodiments of the invention can be found in the dependent claims.

The present invention provides for this purpose a light emitting module, in which an LED and a sensor are accommodated. In the light emitter module, a light guide is inserted during assembly and fixed there. The basic idea of the present invention is to detect the light coupled into the light guide by the LED through the sensor. The sensor transmits the measurement results to a control unit, which in turn controls the LED.

The components mentioned can thus be accommodated in a module in a small space. Also, the sensor needs to be calibrated / tuned only once for a specific module. The control is thus independent of the changing geometry of the light guide.

The control can be used not only for color matching but also for brightness control. Also, the present invention prevents the light emitted from the LED from being adversely affected by the measurement.

In a particular embodiment, it is therefore provided that locking lugs of a light guide, which are provided for its attachment to the module, are used to deflect a small portion of the light coupled into the light guide in the direction of the sensor. For this purpose, this proportion of light is coupled out of the light guide again, and guided to the sensor.

In an alternative embodiment, the sensor is fixed to the housing such that its detection surface is opposite the optical fiber, and the sensor can thus detect the mixed-in light already coupled into the optical fiber.

In a preferred embodiment, the LED is a so-called RGB LED with a plurality of color diodes. Typically, an RGB LED is equipped with a green, a blue and a red color diode. By mixing the individual colors, a broad color spectrum can be realized.

Further, it is preferred that the sensor is calibrated during assembly in the light emitter module with respect to the LED also already mounted in the light emitter module. Thus, the sensor can be adjusted to the conditions in the specific module. This is particularly advantageous if - in the case of an RGB LED - depending on the light emitter module different color components are detected by the sensor.

Thus, the control unit connected to the LED and the sensor based on the measurement data of the sensor can control the LED targeted, and thus set the desired color exactly. It is provided in a further preferred embodiment that the optical fiber used has a diameter between 2-5 mm, preferably about 3.5 mm. The size of about 3.5 mm is a commonly used size. Thus, the light pipe is guaranteed homogeneously over relatively long distances in said diameter range.

In a further embodiment, the sensor has a detection surface facing in the direction of emission of the LED. This makes it possible to realize an extremely compact design.

In a preferred embodiment of the present invention, the LED and the sensor are fixed on a common base. As a result, the relative orientation of the sensor to the LED can be ensured. In particular, a circuit board is used as a common base (PCB = printed circuit board).

For fixing the light guide to the light emitter module, the light guide can have so-called latching noses. These locking lugs are used in one embodiment of the present invention to deflect a portion of the light in the light guide, and to guide this light portion to the sensor. Accordingly, the locking lugs, in addition to the mechanical mounting of the light guide in the light emitting module fulfill another task. The deflected for the measurement with the sensor light reduces the optical fiber property of the light guide only insignificantly, since it is only a small part of the light coupled into the light guide.

In one embodiment, it is provided that the light is reflected at a latching nose in such a way that it again passes in sections through the light guide and exits at a position from the light guide. Then it is detected by the sensor.

In a particular other embodiment, the sensor is fixed to the housing of the light emitting module, preferably encapsulated. In this case, in this embodiment, the sensor is positioned such that it opposes the light guide inserted into the light emitter module, so that it can detect a light coupled into the light guide by the LED.

For this purpose, it is preferably provided that a portion of the light guide on which the sensor is located, is cloudy, so that at this point a part of the light can be coupled out from the light guide and detected by the sensor.

4. Brief description of the drawings

1 shows an exemplary embodiment of the present invention, in which a color sensor is arranged laterally of the light guide in the housing.

2 shows a schematic view of a second embodiment of the present invention, in which a detent of the optical fiber reflects a part of the light to the color sensor.

3 shows a schematic view of a third embodiment of the present invention, which has a similar construction to that in 2 has shown embodiment.

5. Detailed description of the exemplary embodiment

Hereinafter, three preferred embodiments of the present invention will be described with reference to the accompanying drawings.

1 relates to a first embodiment in which the color sensor 2 is integrated in the housing G of the module according to the invention.

This is done on a circuit board 1 an RGB LED 5 applied, at its opposite side an end portion 4a a light guide 4A lies when this light guide 4A was introduced to the module. In 1 this condition is shown.

By RGB LED is meant in the context of this application, a LED (light emitter diode) with multiple diodes. This term includes, for example, RGGBs, RGBWs or similar LEDs. The present RGB LED 5 has several color diodes; in the present embodiment, it is a green light diode 6 , a diode for blue light 7 and a diode for red light 8th , With the help of these diodes 6 - 8th a large color spectrum can be generated.

As the end section 4a of the light guide 4A the RGB LED 5 is opposite from that of the RGB LED 5 generated light in the light guide 4A coupled. The detection of the well-mixed light in the light guide by means of the color sensor 2 , which can be a true color sensor or RGB sensor.

The sensor 2 Was either cast directly in the manufacture of the housing G in this case, or fixed there in a subsequent assembly step (for example by clipping). Due to the fixing of the light guide in the housing, there are no positioning problems between the color sensor 2 and light guides 4A ,

The fixation of the RGB LED 5 at the light guide 4A This can be done by the circuit board 1 is pressed to the corresponding side of the housing G, thereby positioning takes place and thus a position fixation of the components RGB LED / optical fiber / sensor is ensured.

The detection section of the sensor 2 is in the present embodiment perpendicular to the longitudinal direction of the light guide 4A aligned. Thus, a detection of the already in the light guide 4A located light, which has the advantage that the light is already mixed enough. The well-mixed light is at a point of the light guide to which the color sensor 2 is again decoupled from the light guide. For this purpose, this region of the optical waveguide lying opposite the sensor can be roughened in order thus to ensure the exit of a small part of the light coupled in the optical waveguide.

Another embodiment of the present invention is in 2 shown. As in the first embodiment, an RGB LED 5 on a circuit board 1 appropriate. Opposite the RGB LED 5 , which in turn has multiple color diode 6 - 8th has, is the end portion of an inserted into the module light guide 4B ,

The light guide 4B is in this embodiment with locking lugs 4b provided, which engage in the housing G and the light guide 4B with respect to the housing G, and thus with respect to the circuit board 1 fix. As on the circuit board 1 both the RGB LED 5 as well as a color sensor 2 attached to defined positions, this ensures the relative position of said components to each other.

For the detection of the in the light guide 4B well mixed with light (rays of light 6a - 8a ) is from the color sensor 2 detects a scattered light from one of the locking lugs 4b through the light guide 4B through back to the color sensor 2 is reflected.

This embodiment is based on the finding that in the presence of latching lugs on a light guide there is always a scattering of the coupled-in light. In this case, this scattering is used without additional light at the coupling-in point (end section 4a ). This has the advantage that the light intensity in the light guide 4B is not attenuated.

In 3 another embodiment of the present invention is shown, whose principle is similar to the second embodiment. However, in this third embodiment, the light at the latch is not within the light pipe 4B reflected, but from the catch 4b deflected or scattered over a recess within the housing to the outside. This scattered to the outside light in turn passes through a further recess in the housing G on the on the circuit board 12 fixed sensor. This has the advantage over the second embodiment that the light is only reflected once (namely at the in 3 illustrated right latch 4b ), while in the second embodiment after the reflection at the detent further distractions of the light at the exit from the light guide into the interior of the housing G can be expected.

In the embodiments 2 and 3 ( 2 and 3 ) there are different possibilities, the color sensor 2 on the circuit board 1 to fix. One possibility is to use contact pins on the circuit board 1 to install and provide in the housing G guide slots for the pins. On the sensor, a receptacle for the contact pins is provided at the individual outputs. The recording between the springs on the color sensor 2 is smaller than the contact pin diameter, so that a latching of the contact pin and thus a solid contact can be ensured.

Another option is to use the contact pins on the color sensor 2 provided. The contacting with the circuit board is done via so-called mqs-section-pins. For this purpose, contact holes are made available on the board, which are smaller in diameter than the contact pins. When pressing the contact pins in the holes material is plastically deformed in the holes, and thus the contact pins engage firmly.

The module of RGB-LED shown in Embodiments 1-3 5 , Color sensor 2 , Optical fiber 4A -B as well as the housing G has the advantage that the color sensor 2 must be calibrated and adjusted only once during assembly of the module. In the case of a changing geometry of the light guide no re-vote must be made. Furthermore, the control can be used not only for color matching, but generally for brightness control.

Accordingly, a wide range of industrial applicability of the present invention opens up. Preferably, this is used for a so-called ambient or effect lighting, for example in an automobile. However, a signal lighting in case of danger or a functional lighting is conceivable. Also, the present module can be constructed as an optical switch when z. B. an activity (such as a touch) with a finger to change the properties of the light, and this is detected to the sensor.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102006099551 B4 [0006]
• DE 102008039364 A1 [0007]
• DE 102008025865 A1 [0008]

Claims (13)

A light emitting module comprising: an LED ( 5 ) and a sensor ( 2 ), the LED ( 5 ) and the sensor ( 2 ) are connected via a control unit, one that can be inserted into the module, the LED ( 5 ) opposite light guide ( 4A -B), and a housing (G) in which the LED ( 5 ) and the sensor ( 2 ), the sensor ( 2 ) is arranged so that it is one of the LED ( 5 ) in the light guide ( 4A ) and one again from the light guide ( 4B ) can detect outcoupled light. A light emitting module according to claim 1, wherein the LED ( 5 ) an RGB LED is provided with a plurality of color diodes, in particular a green, a blue and a red color diode ( 6 - 8th ). Light emitter module according to one of the preceding claims, in which the sensor ( 2 ) when mounting with respect to the LED mounted in this light emitting module ( 5 ) is calibrated. Light emitter module according to one of the preceding claims, wherein the control unit based on the measurement data of the sensor ( 2 ) the LED ( 5 ) can control. Light emitter module according to one of the preceding claims, in which the light guide ( 4A -D) has a diameter of 2 to 5 mm, preferably about 3.5 mm. Light emitter module according to one of the preceding claims, in which the sensor ( 2 ) has a detection surface which is in the emission direction of the LED ( 5 ). Light emitter module according to one of the preceding claims, in which the LED ( 5 ) and the sensor ( 2 ) on a common basis ( 1 ), in particular a printed circuit board, are fixed. Light emitter module according to one of the preceding claims, in which the light guide ( 4B ) Latching lugs ( 4b ), in which a part of the in the light guide ( 4B ) is coupled deflected light. Light emitter module according to claim 8, in which the latching lugs ( 4b ) the light guide ( 4B ) at the light emitter module. Light emitter module according to claim 8 or 9, in which the light is thus applied to a detent ( 4b ) is reflected, that it in turn passes through the light guide and exits the light guide. Light emitter module according to claim 8 or 9, in which the light is thus applied to a detent ( 4b ) is reflected, that it at the detent ( 4b ) exits the light guide. Light emitter module according to one of claims 1-5, wherein the sensor ( 2 ) is fixed to the housing (G) of the light emitting module, is preferably cast in, and thus the optical fiber ( 4A ) is opposite to that of the LED ( 5 ) in the light guide ( 4A ) can detect coupled-in light. A light emitting module according to claim 12, wherein the sensor 2 opposite section of the light guide ( 4A ) is roughened.

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