JPH01211981A - Composite type light emitting device - Google Patents

Abstract

PURPOSE:To enable discrimination by observing only one displayed part for status perception applying a plurality of luminous colors, by encapsulating several kind of light emitting diode elements having different luminescent colors in the same light scattering package, and synthesizing the combination of said luminescent colors in one color. CONSTITUTION:A voltage is applied between an external anode terminal 21 being a common electrode and an external cathode terminal 22 or 23 being an individual electrode. When the voltage is applied only between 21 and 22, a first emitting diode element 11 only emits light, and when the voltage is applied only between 21 and 23, a second light emitting diode element 12 only emits light. When the voltage is applied at the same time between 21 and 22 and between 21 and 23, both diodes emit light. The emission spectra of the light emitting diodes 11, 12 are different and the diodes are arranged nearly. The two lights are scattered by a light scattering package, so that a third luminous color corresponding the synthesized emission spectrum of the two lights is obtained. Thereby a plurality of luminescent colors are made available containing a luminescent color not emitted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical semiconductor device, and more particularly to a composite light emitting device that converts an electrical signal into an optical signal and utilizes a wavelength range of visible light.

[Conventional technology]

Among such optical semiconductor devices, light emitting diodes have traditionally been realized using PN junctions, and the widely used emission colors are red, green, amber, etc., and they are assembled individually for each different emission color. It is being

FIG. 3 is a perspective view showing the structure of a conventional light emitting diode. Even though there is a difference in the emitted light color, the structure is basically the same. In Fig. 3, 1 is a light emitting diode element, 2
1.22 are respective external anode terminals and external cathode terminals; 3 is a light scattering package; 0 The anode of the light emitting diode element is connected to the external anode terminal by a wire bonding, and the cathode is connected to the bonding wire 4 of the external cathode terminal 22; Connected. By passing a current of a predetermined amount or more to this light emitting diode element 1, it emits light,
Light is scattered by the light scattering package 3, and the entire 3 becomes colored.

[Problem to be solved by the invention]

Conventional light emitting diodes are aimed at emitting a single color. Therefore, as an application example, it is often used for systems that notify whether the current is on or off.On the other hand, in order to identify multiple states by a combination of colors, diodes with different light emitting colors are prepared, and these A system is adopted in which notification is provided based on a combination of energized states. At this time, arranging a plurality of diodes increases the display area for front display, for example, or requires other means to make it clear that the plurality of diodes are one unit. In addition, since it was based on a combination of colors, it had less power to appeal to human vision than a single luminescent color. Therefore, it has been desired to be able to emit light of different colors using the same light emitting diode.

[Means to solve the problem]

The present invention has the following configuration in order to expand the range of applications described above, reduce the display area, and be suitable for color identification applications.

That is, the composite light emitting device of the present invention includes a plurality of light emitting diode elements emitting light of different colors, one external anode (or cathode) terminal commonly connected to the anodes (or cathodes) of the light emitting diode elements, and the It includes a plurality of external cathode (or anode) terminals each individually connected to the cathode (or anode) of a light emitting diode element, and a light scattering type package that seals the light emitting diode element.

〔Example〕

Next, the present invention will be explained using the drawings.

FIG. 1 is a perspective view of an embodiment of the present invention, and FIG. 2 is a circuit diagram thereof.

Although this embodiment shows the case where the number of the plurality of light emitting diode elements is two, the same applies to the case where the number of the plurality of light emitting diode elements is three. In FIG. 2, 11 is a first light emitting diode element, 12
2 is a second light emitting diode element, 21 is a common external anode terminal, 22 and 23 are individual external cathode terminals of the two light emitting diodes and corresponding electrodes, and 3 is a light scattering type package. The first light emitting diode element 11 and the second light emitting diode element 12 are connected to one common electrode (21) with their polarities aligned, for example, in FIG. 1, with the anode being common. On the other hand, regarding the other polarity, the cathode (K1) of the first light emitting diode element 11 is connected to the electrode (22), and the cathode (K1) of the second light emitting diode element 12 is connected to the electrode (22).
K2) is connected to the electrode (23). These first and second light emitting diode elements 11 and 12 are enclosed in a common light scattering package 3.

Next, in order to operate this, a voltage is applied between the external anode terminal 21 (A), which is a common electrode, and the external cathode terminal 22 (Kl) or 23 (K2), which is an individual electrode. If the voltage is applied only between 21 and 22, only the first light emitting diode element 11 will emit light; similarly, if the voltage is applied only between 21 and 23, only the second light emitting diode element 12 will emit light. Moreover, if the voltage is applied to both of them, that is, 21, 22, and 23 at the same time, both of them will have a light color. At this time, the emission spectra of the first and second light emitting diode elements are different, they are arranged spatially close to each other, and they are scattered by the light scattering package, so the obtained emission color differs from that of both. A third emission color is obtained that corresponds to the emission spectrum of the combined form. In addition, in order to prevent any of the light emitting diode elements from producing color, it is necessary to apply a voltage between the electrodes 21-22 and 21-23. A total of four emitted colors can be obtained.

Although the case where two light emitting diode elements 2 are used has been described above, when three light emitting diode elements 2 are used, eight types of emitted light colors can be obtained.

In addition, in the above explanation, it is assumed that the current value flowing through each light emitting diode element is a certain constant value and is applied between the electrodes, but in general, by changing the current value flowing through each diode, it is possible to It is also possible to obtain different coloring effects that are not continuous but continuous.

Note that the scattering type package may be the same as the conventional one, such as a transparent resin mixed with an appropriate powder.

〔Effect of the invention〕

As explained above, the present invention firstly enables a plurality of light emitting diode elements emitting different light emitting colors to be sealed in the same light-scattering package and combining the light emitting colors into one color. It produces a psychological effect on state perception based on the color of the emitted light, which can be understood just by looking at a single display area, and secondly, it has the effect of eliminating the increase in area of the display area when multiple light emitting diodes are lined up at the same time. . Thirdly, it produces the effect that it is possible to continuously obtain different colors depending on the combination of the magnitude of the current value applied to each diode.
The light emitting diode element can be selected arbitrarily from the conventionally known colors such as red, green, and amber, and it goes without saying that a variety of colors can be prepared depending on the system to be applied. In the case of a combination of green, which provides safety, and red, which provides danger, the color of this diode becomes green when the device is in normal operating condition.
The same diode can be used to turn red in abnormal operating conditions and amber in intermediate conditions.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a circuit diagram thereof, and FIG. 3 is a perspective view of a conventional example. DESCRIPTION OF SYMBOLS 1... Light emitting diode element, 3... Light scattering type package, 4.5... Bonding line, 11... First light emitting diode element, 12... Second light emitting diode element, 21. ...External anode terminal, 22...External cathode terminal, 23...External anode terminal.

Claims (1)

[Claims] a plurality of light emitting diode elements emitting light of different colors; one external anode (or cathode) terminal commonly connected to the anodes (or cathodes) of the light emitting diode elements;
A composite comprising a plurality of external cathode (or anode) terminals each individually connected to the cathode (or anode) of the light emitting diode element, and a light scattering type package that seals the light emitting diode element. type light emitting device.