JP4239357B2 - Diffuse light emitting device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a diffusion light-emitting device that diffuses and transmits an optical signal.
[0002]
[Prior art]
In recent years, techniques using optical wireless in data transmission between digital devices have been developed.
[0003]
FIG. 6 is a perspective view showing a configuration of a light emitting device used in a conventional optical wireless. The light-emitting device shown in FIG. 1 includes a thin columnar fixing plate 61 that can be installed on the ceiling 3 and a plurality of LEDs (Light Emitting) connected to the lower surface of the fixing plate 61 via lead wires 68b and arranged in an annular shape. Diode) 64, a fixing portion 67 that fixes each LED 64, a plurality of LEDs 62 that are further annularly arranged outside the ring on which the LEDs 64 are arranged and are connected to the lower surface of the fixing plate 61 via lead wires 68a, A fixing portion 66 for fixing the LED 62, a light receiving portion 63 for receiving an optical signal from a slave unit (not shown), and an annular center where the light receiving portion 63 is disposed on the lower surface of the fixing plate 61 and the LEDs 62 and 64 are arranged. This is a configuration having a columnar support portion 65 supported at a predetermined height on the portion and a signal processing device 69 disposed on the upper surface of the fixed plate 61 so as to be located behind the ceiling.
[0004]
The signal processing device 69 is connected to a transmission cable 70 formed by a metal cable, an optical fiber, or the like arranged behind the ceiling, and is connected to a server or an information network via the transmission cable 70. In addition, what is arrange | positioned in the ceiling back in the figure is shown with the dotted line.
[0005]
In the transmission of the optical signal, the signal processing circuit 69 performs a predetermined process on the data signal transmitted from the transmission cable 70 and transmits it to the LEDs 62 and 64. Each LED 62, 64 converts an electrical data signal into an optical signal and transmits it to an indoor slave unit.
[0006]
In receiving the optical signal, the optical signal transmitted from the slave unit is received by the light receiving unit 63 and converted into an electric signal. The photoelectrically converted data signal is transmitted to a server or the like via the signal processing device 69 and the transmission cable 70.
[0007]
In this light emitting device, the direction of each LED 62, 64 is fixed to a desired angle by changing the shape of each lead wire 68a, 68b of each LED 62, 64. The LED 62 provided on the outer side of the double ring is oriented so that the optical signal reaches far away, and transmits the optical signal in a narrow directivity system. On the other hand, the LED 64 provided on the inner side of the double ring is oriented so that the optical signal reaches vertically below or in the vicinity thereof, and transmits the optical signal in a wide directivity system.
[0008]
[Problems to be solved by the invention]
However, the conventional light emitting device has the following problems.
[0009]
(1) Since the LEDs 62 and 64 must be arranged in a ring and fixed by the lead wires 68a and 68b and the fixing portions 66 and 67, the manufacturing process is complicated and the manufacturing efficiency and the position accuracy are low.
[0010]
(2) Since each LED 62 and 64 generates heat, it is necessary to take measures against heat dissipation.
[0011]
(3) When changing the orientation of the LEDs 62 and 64, it is necessary to change the shape of the lead wires 68a and 68b for fixing the LEDs 62 and 64, which takes a lot of trouble.
[0012]
(4) Since the lead wires 68a and 68b are long, the lead wire has an inductance component during high-speed transmission, and the signal waveform deteriorates.
[0013]
The present invention has been made in view of the above, and an object of the present invention is to provide a diffused light-emitting device that can contribute to improvements in productivity, heat dissipation, and convenience of use.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, a diffused light emitting device according to the present invention includes a plurality of light emitting elements on a plane of a fixed portion having a plane, in a multiple annular shape centering on an axis orthogonal to the plane. Light emitting means mounted so as to be arranged so that the axis and the optical axis of each light emitting element are substantially parallel, a first surface for entering light emitted from the plurality of light emitting elements, and light on the axis A circumferential surface that decreases in diameter as it approaches the optical transmission source side from the transmission destination side, and the angle of the circumferential surface with respect to the axis is from the light emitting element group that is incident from the first surface and arranged in an annular shape. A second surface that is the peripheral surface for reflecting the incident light differently for each of the incident light, and a third surface for transmitting the reflected light reflected by the second surface to be emitted to the outside, characterized by comprising a diffusion means having a diffusion lens having.
[0015]
In the present invention, since the plurality of light emitting means are directly attached to the fixing plate without using the lead wires, it becomes unnecessary to fix the light emitting means with the lead wires or the fixing members as in the prior art. , Productivity and position accuracy can be improved.
[0016]
Moreover, since the heat generated by the light emitting means is radiated by the fixing plate to which the light emitting means is attached, the heat dissipation can be improved with a simple configuration.
[0017]
Furthermore, since no lead wire is required, it is possible to prevent deterioration of the signal waveform due to the inductance component of the lead wire.
[0018]
Further, by providing a diffusing unit that diffuses the optical signal with a predetermined light distribution, the transmission range of the optical signal can be secured with a wide directivity angle, and the intensity of the optical signal can be made substantially uniform within the predetermined range. .
[0020]
Further, by arranging a plurality of light emitting means in a ring shape, an optical signal is transmitted substantially uniformly around.
[0022]
Further, since the diffusing means is formed by a diffusing lens using a transparent member such as acrylic or polycarbonate, the optical signal is hardly absorbed and the optical signal can be used efficiently.
[0024]
In addition, the optical signal incident from the incident surface of the diffusing lens is reflected by the reflecting surface and then transmitted through the transmitting surface, so that the optical signal is sufficiently diffused and the range in which the optical signal can be transmitted is wide. Can be secured. In addition, since the transmission surface is arranged substantially perpendicular to the fixed plate and formed into an annular shape, the optical signal is diffused substantially uniformly without leaking, so that the optical signal can be used with high efficiency.
[0027]
Further, in the above diffused light-emitting device, the plurality of the part of the incident light from the light emitting element emitted light, for deriving as is emitted to the outside through the second face Incident angle changing means is provided on the first surface .
[0028]
In the present invention, an incident angle changing means formed by, for example, a groove for changing the incident angle of the optical signal is provided on the incident surface. It can be transmitted or the angle of reflection on the reflecting surface can be changed, and the optical signal can be diffused vertically downward or in the vicinity thereof.
[0031]
Further, in the above diffused light-emitting device, a plurality of inner part of the fixed part is of light emitting elements arranged in multiple annular light emitting means is emitted from the second surface of the diffusion lens injection A reflection means for reflecting light is provided.
[0032]
In the present invention, since the reflected without optical signal emitted by the plurality of light emitting means is absorbed by the reflecting means, it is possible to utilize the optical signal with high efficiency.
[0033]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0034]
FIG. 1A is a perspective view showing the configuration of the diffusion light emitting device according to the present embodiment, and FIG. 1B is a perspective view showing the state of the lower surface of the fixing plate 11 when the diffusion lens 12 is removed. FIG.
[0035]
The diffuse light-emitting device 1 shown in FIG. 1 includes a thin columnar fixing plate 11 that can be installed on a ceiling 3, and a plurality of LEDs 14 that are arranged in a double ring shape on the lower surface of the fixing plate 11 and are directly attached by surface mounting. And a light receiving unit 13 that receives an optical signal from a slave unit (not shown), and a cylindrical shape that supports the light receiving unit 13 at a predetermined height on the lower surface of the fixing plate 11 and at the center of the double ring of the LED 14 , A diffusing lens 12 that is detachably arranged on the lower surface of the LED 14 on the lower surface of the fixed plate 11, and a signal that is disposed on the upper surface of the fixed plate 11 so as to be located behind the ceiling. The configuration includes a processing device 19.
[0036]
The support portion 15 is formed of a shielding member, and its surface is subjected to a mirror finish so that an optical signal is reflected.
[0037]
The diffusion lens 12 is formed of a transparent member having a refractive index of about 1.45 to 1.65, such as acrylic or polycarbonate, and diffuses an optical signal emitted from each LED 14.
[0038]
The signal processing device 19 is connected to a transmission cable 20 formed by a metal cable, an optical cable, or the like disposed behind the ceiling, and is connected to a server, an information network, or the like via the transmission cable 20.
[0039]
In FIG. 4A, those arranged behind the ceiling are indicated by dotted lines, and in FIG. 4B, the signal processing device 19 and the transmission cable 20 are omitted.
[0040]
As shown in FIG. 5B, each LED 14 is directly attached to the fixing plate 11 without a lead wire or a fixing member. For this reason, the range in which each LED 14 transmits an optical signal becomes a narrow range vertically downward. Therefore, a diffusing lens 12 is provided so that an optical signal can be transmitted over a wide range.
[0041]
FIG. 2 is a cross-sectional view showing the configuration of the diffuse light emitting device 1. In the drawing, a desirable shape of the diffusing lens 12 is shown, and details thereof will be described later.
[0042]
FIG. 3 is a diagram illustrating a usage mode of the diffuse light emitting device 1. The diffuse light-emitting device 1 is installed on a ceiling 3 and a slave unit 2 is arranged in the same room. The subunit | mobile_unit 2 is corresponded to the personal computer, digital camera, AV (Audio Visual) apparatus etc. which have the transmission / reception function by optical wireless. The diffuse light emitting device 1 converts a data signal transmitted from a server or the like via a transmission cable 20 into an optical signal by each LED 14 and transmits the optical signal to the slave unit 2 by the diffusion lens 12. In addition, the optical signal transmitted from the slave unit 2 is received by the light receiving unit 13, subjected to photoelectric conversion, and transmitted to a server or the like via the transmission cable 20.
[0043]
FIG. 4 is a diagram illustrating an example of a communication range of optical signals by optical radio. Now, consider that a uniform optical signal intensity can be obtained within a predetermined range. Here, the position of the diffuse light-emitting device 1 is set to a directivity angle of 0 °, and the position along the floor surface 4 at a distance of 3 m vertically downward from the diffuse light-emitting device 1 in the range up to about ± 53 ° around this position. When the directivity angle is in the range of + 53 ° to + 65 ° or −53 ° to −65 °, the intensity of the optical signal is uniformly obtained at a distance of 5 m from the diffuse light emitting device 1. In the figure, the range in which the intensity of the optical signal is uniform is indicated by a thick line.
[0044]
FIG. 5 is a graph showing the theoretical value of the required radiation intensity that the diffuse light-emitting device 1 should distribute in order to obtain a uniform optical signal intensity in such a predetermined range. In the figure, the horizontal axis indicates the directivity angle (°) with respect to the diffuse light-emitting device 1, the left vertical axis indicates the required radiation intensity (relative value with respect to the directivity angle 0 °), and the right vertical axis indicates the diffuse light-emitting device 1 (master unit). And the distance (m) between the slave unit 2 and the slave unit 2 respectively.
[0045]
When the directivity angle of the handset 2 disposed on the floor 4 with respect to the diffuse light emitting device 1 is gradually increased from 0 °, the distance between the diffuse light emitting device 1 and the handset 2 gradually increases as shown by the broken line in FIG. Will increase. It is known that as the distance increases, the intensity of the optical signal attenuates by 1 / (distance ² ). From this, the required radiation intensity of the optical signal to be distributed by the diffuse light-emitting device 1 increases in proportion to (distance ² ) as shown by the solid line in FIG.
[0046]
Next, the shape of the diffusing lens 12 for distributing an optical signal according to such a light distribution curve will be described with reference to the cross-sectional view shown in FIG.
[0047]
The diffusing lens 12 in the figure has a configuration having incident surfaces e and d, reflecting surfaces a and b, and a transmitting surface c.
[0048]
The incident surface e is a circular shape that is substantially parallel to the lower surface of the fixed plate 11 and has a hollow upper surface, and makes an optical signal emitted from each LED 14 enter the diffusing lens 12.
[0049]
The incident surface d is a surface in contact with the outer circumference of the incident surface e and the lower surface of the fixed plate 11, and is provided at an angle D of about 0 to 90 ° with respect to a surface perpendicular to the fixed plate 11.
[0050]
The reflection surface a is a surface in contact with the inner circumference of the incident surface e and the reflection surface b, and is directed outward by an angle A of about 30 to 50 ° with respect to a surface perpendicular to the fixed plate 11. The reflection surface a mainly reflects the optical signal emitted from each LED 14 arranged inside the double ring and incident from the incident surface e. The angle A is determined based on the refractive index ratio between the diffusing lens 12 and air so that the optical signal can be totally reflected on the reflecting surface a.
[0051]
The reflection surface b is a surface in contact with the reflection surface a and the transmission surface c, and is directed outward by an angle B of about 35 to 55 ° with respect to a surface perpendicular to the fixed plate 11. The reflection surface b mainly reflects the optical signal emitted from each LED 14 arranged outside the double ring and incident from the incident surface e. The angle B is determined based on the refractive index ratio between the diffusing lens 12 and air so that the optical signal can be totally reflected on the reflecting surface b.
[0052]
The transmission surface c is an annular surface in contact with the reflection surface b and the lower surface of the fixed plate 11, and is directed inward by an angle C of about 0 to 10 ° with respect to a surface perpendicular to the fixed plate 11. The transmission surface c transmits the optical signal incident from the incident surface d and the optical signal reflected by the reflection surfaces a and b.
[0053]
Further, the incident surface e is provided with a notch portion 16 having a V-shaped cross section for changing the incident angle of the optical signal. The notch 16 has a notch 16 with respect to the incident surface e so that an optical signal incident from the notch 16 can be transmitted through the reflecting surfaces a and b or the reflection angle at the reflecting surfaces a and b can be changed. The angle of the wall surface is determined.
[0054]
The outer diameter of the support portion 15 is about 40 to 50 mm, for example, and the distance D2 from the central axis of the support portion 15 to the inside of the diffusing lens 12 is about 30 to 60 mm. The distance D1 from the inside to the outside of the diffusing lens is about 20 to 50 mm, and the height H of the diffusing lens 12 is about 30 to 50 mm. The height of the support portion 15 is preferably shorter, but if it is too short, it becomes difficult to receive the optical signal from the slave unit. Therefore, the height is set to an appropriate length within a range shorter than the height H in consideration of this.
[0055]
In such a diffusing lens 12, an optical signal incident from the incident surface e and directed to the reflecting surfaces a and b is totally reflected, passes through the transmitting surface c, and diffuses outward. An optical signal incident from the incident surface e and not directed to the reflecting surfaces a and b is reflected by the transmitting surface c, passes through the reflecting surface b, and diffuses vertically below or in the vicinity thereof. The optical signal incident from the incident surface d is transmitted through the transmission surface c and diffused outward. The optical signal incident from the notch 16 and directed toward the reflection surfaces a and b is transmitted through the reflection surfaces a and b and diffused vertically downward or in the vicinity thereof.
[0056]
The optical signal directed from the incident surfaces d and e to the support unit 15 without entering the diffusing lens 12 is reflected by the mirror-treated surface of the support unit 15 and diffuses vertically downward or in the vicinity thereof.
[0057]
Therefore, according to the present embodiment, since the plurality of LEDs 14 are directly attached to the lower surface of the fixing plate 11, it is not necessary to fix the LEDs with lead wires or fixing members as in the prior art. And position accuracy can be improved.
[0058]
Further, according to the present embodiment, the heat generated by each LED 14 is radiated by the fixed plate 11 to which each LED 14 is attached or the surface cover of the signal processing device 69 provided on the upper surface of the fixed plate 11. Heat dissipation can be improved with a simple configuration.
[0059]
Furthermore, according to the present embodiment, the lead wire of the LED becomes unnecessary, so that the deterioration of the signal waveform due to the inductance component of the lead wire can be prevented.
[0060]
Further, according to the present embodiment, by providing the diffusion lens 12 that diffuses the optical signal according to the predetermined light distribution, the transmission range of the optical signal can be secured with a wide directivity angle, and the optical signal can be transmitted within the predetermined range. The strength can be made substantially uniform.
[0061]
Furthermore, according to the present embodiment, by arranging the transmission surface c substantially perpendicular to the fixed plate 11 and making it annular, the optical signal transmitted through the transmission surface c is diffused substantially uniformly without leaking. Optical signals can be used with high efficiency.
[0062]
In addition, according to the present embodiment, the installation angles of the reflecting surfaces a and b are determined based on the ratio of the refractive index of the diffusing lens 12 and air so that the optical signal is totally reflected. Compared with the case where gold or the like is used for the reflecting surface, there is no absorption of light on the reflecting surface, and an optical signal can be used with high efficiency.
[0063]
Furthermore, according to the present embodiment, the notch 16 for changing the incident angle of the optical signal is provided on the incident surface e, and the optical signal incident from the notch 16 can be transmitted through the reflecting surfaces a and b. Alternatively, the angle of the wall surface of the notch 16 with respect to the incident surface e is determined so that the reflection angle at the reflection surfaces a and b can be changed, so that the optical signal is diffused vertically downward or in the vicinity thereof. Therefore, a wide transmission range of the optical signal can be secured.
[0064]
In addition, according to the present embodiment, since the diffusion lens 12 is detachably installed on the lower surface of the fixed plate 11, by replacing the diffusion lens with a diffusion lens having a different material and shape, an arbitrary one can be obtained. The light distribution of the optical signal in the range and intensity can be easily realized.
[0065]
Furthermore, according to the present embodiment, the surface of the support unit 15 that supports the light receiving unit 13 at a predetermined height is mirror-finished, so that the optical signal emitted by each LED 14 is absorbed by the surface of the support unit 15. Therefore, the optical signal can be used with high efficiency.
[0066]
In the present embodiment, the LEDs 14 are arranged in a double ring shape, but may be a single ring or a multiple ring depending on the size of the room in which the diffused light emitting device is arranged. In such a case, a diffusing lens matched to the annular size is prepared.
[0067]
In the present embodiment, diffusion light emitting device 1 is arranged on the ceiling, but is not limited to the ceiling, and may be arranged, for example, on a wall or a predetermined fixed base.
[0068]
【The invention's effect】
As described above, according to the present invention, since the plurality of light emitting means are directly attached to the fixing plate without using the lead wires, the light emitting means are fixed by the lead wires or the fixing members as in the past. Therefore, productivity and position accuracy can be improved.
[0069]
Moreover, since the heat generated by the light emitting means is radiated by the fixing plate to which the light emitting means is attached, the heat dissipation can be improved with a simple configuration.
[0070]
Furthermore, since no lead wire is required, it is possible to prevent deterioration of the signal waveform due to the inductance component of the lead wire.
[0071]
Further, by providing a diffusing unit that diffuses the optical signal with a predetermined light distribution, the transmission range of the optical signal can be secured with a wide directivity angle, and the intensity of the optical signal can be made substantially uniform within the predetermined range. .
[Brief description of the drawings]
FIG. 1 is a perspective view showing a configuration of a diffuse light-emitting device 1 according to the present embodiment.
2 is a cross-sectional view showing a configuration of a diffuse light-emitting device 1 according to the present embodiment. FIG. 3 is a diagram showing a use mode of the diffuse light-emitting device 1. FIG.
FIG. 4 is a diagram illustrating an example of an optical wireless communication range.
FIG. 5 is a graph showing a theoretical value of necessary radiation intensity to be distributed by the diffuse light-emitting device 1;
FIG. 6 is a perspective view illustrating a configuration of a conventional light emitting device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Diffuse light-emitting device 2 Child machine 3 Ceiling 4 Floor surface 11 Fixed plate 12 Diffusing lens 13 Light-receiving part 14 LED
DESCRIPTION OF SYMBOLS 15 Support part 19 Signal processing apparatus 20 Transmission cable 61 Fixing plate 62 Narrow directivity angle type LED
63 Light-receiving unit 64 LED with wide directivity
66 Fixing portion 67 of LED 62 Fixing portions 68a and 68b of LED 64 Lead wire 69 Signal processing device 70 Transmission cable

Claims (3)

A plurality of light emitting elements are arranged on the plane of the fixed portion having a plane in a multiple annular shape around an axis orthogonal to the plane so that the axis and the optical axis of each light emitting element are substantially parallel to each other. Light emitting means arranged and mounted ;
A first surface on which light emitted from the plurality of light emitting elements is incident, and a peripheral surface that is reduced in diameter as it approaches the optical transmission source side from the optical transmission destination side on the axis, the peripheral surface of the peripheral surface A second surface which is the circumferential surface for reflecting the incident light from the light emitting element group incident from the first surface and having an angle with respect to the axis different from each other. A diffusing unit provided with a diffusing lens having a third surface for transmitting the reflected light reflected by the surface of 2 and emitting it to the outside ;
A diffused light emitting device comprising: Incident angle changing means for deriving a part of the incident light from the plurality of light emitting elements so as to be transmitted through the second surface and emitted to the outside is provided on the first surface. diffused light-emitting device according to claim 1, characterized in that provided. Reflecting means for reflecting the emitted light emitted from the second surface of the diffusing lens is provided on a portion of the fixed portion that is inside the plurality of light emitting elements arranged in a multiple annular shape of the light emitting means. The diffuse light-emitting device according to claim 2.

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