JP3929565B2 - Illuminated switch - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an illumination type switch used for an operation panel of a mobile communication device, a measuring device, a medical device, an in-vehicle electronic device or the like.
[0002]
[Prior art]
As a conventional click type illuminated switch, a self-illuminated tact switch as shown in FIG. 3 or a switch in which a light emitting diode (LED) 22 is arranged beside the switch 21 as shown in FIG. 4 is known.
[0003]
The present applicant has proposed an illuminated switch of a planar light emitting body as shown in FIG. 5 in Japanese Patent Application No. 7-219450. In the illumination type switch according to the present invention, the planar light-emitting body EL is disposed directly below the transparent key 23, so that there is no uneven illumination and is superior to other methods in reducing the thickness.
[0004]
[Problems to be solved by the invention]
The one using the self-illuminated tact switch shown in FIG. 3 is thicker and cannot cope with the reduction in thickness and weight of the device.
[0005]
Further, as shown in FIG. 4, the switch using the light emitting diode 22 as a light source has a limit on the absolute number of light emitting diodes that can be used for one product because the power consumption of the LED is large. LEDs are arranged. Therefore, the brightness varies depending on the key.
[0006]
Even if the number of switches is small and can be arranged on each key, especially when arranged just below the key, the structure becomes complicated and a great cost is required.
[0007]
Further, even in the planar light emitting illuminated switch disclosed in Japanese Patent Laid-Open No. 7-219450, since portable devices tend to be smaller and lighter, further reduction in thickness and weight are required.
[0008]
[Means for Solving the Problems]
The present invention uses an EL element that does not have uneven illumination and can be thinned as a backlight of an illuminated switch, and has a dome shape together with a transparent or translucent thermoplastic resin of the uppermost layer of the EL element or a transparent electrode layer of the next layer. It is embossed and used as a click-type spring part, and a hollow structure is formed by cutting out the center part of the lower EL element, so that the lower EL element can be used as a spacer to further reduce the thickness and weight. It was realized.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, a transparent or translucent thermoplastic resin 3 with a transparent electrode layer 4 as the uppermost layer of an EL element such as polyethylene terephthalate or polyethylene naphthalate having a thickness of 75 to 250 μm was formed into a dome shape by embossing. If the thickness of the resin is less than 75 μm, the resilience is weak and reversal is likely to occur, and if it exceeds 250 μm, the embossing moldability is weak.
[0010]
Further, an insulating layer 11 is formed on the inner surface of the dome-shaped transparent electrode layer 4.
[0011]
Then, the upper contact portion 10 is formed in the central portion of the insulating layer 11 . A central portion corresponding to the upper dome portion of the light emitting layer 5, the dielectric layer 6, the back electrode layer 7 and the insulating layer 8 constituting another EL element located below is cut out, and the lower substrate 12 has a lower electrode. 13 is formed. These EL elements can be easily formed by screen printing, vapor deposition, etc., which are known techniques. A hemispherical emboss shape can also be easily formed by a mold, a jig or the like using a known technique.
[0012]
In addition, the lowermost insulating layer 8 is preferably formed thick so as to also serve as a spacer.
[0013]
[Example 1]
FIG. 1 shows an embodiment of the present invention.
[0014]
A transparent electrode layer 4 made of ITO or the like is processed into a film shape by vapor deposition or the like on the lower surface of the transparent thermoplastic resin 3 that can be bent elastically deformed, and this is embossed into a dome shape. The contact layer 10 corresponding to the lower electrode 13 of the lower substrate 12 is provided, and the light emitting layer 5, the dielectric layer 6, and the back surface are sequentially provided below the dome rising portion position below this. The electrode layer 7 and the insulating layer 8 are laminated by screen printing in the same manner as a known EL element structure to form a hollow planar light emitter.
[0015]
In order to provide a better click feeling, a spacer 9 having an appropriate thickness is provided on the laminated insulating layer 8 on the bottom surface, and the lower electrode 13 provided on the lower substrate 12 and the upper contact portion 10 are aligned. The display unit 1 is fixed to the upper part with an adhesive 2.
[0016]
In addition, the spacer was abbreviate | omitted by giving the insulating layer 8 thickness.
[0017]
[Example 2]
FIG. 2 shows another embodiment of the present invention.
[0018]
A transparent thermoplastic resin 3 that can be bent and elastically deformed is embossed in a dome shape, and a contact portion 10 corresponding to the lower electrode 13 of the substrate 12 is provided in the center of the inside thereof. In addition, the transparent electrode layer 4, the light emitting layer 5, the dielectric layer 6, the back electrode 7 and the insulating layer 8 are laminated by screen printing in the same manner as the structure of a known EL element to form a hollow planar light emitter, The inner diameter end face of the transparent electrode layer 4 was used as the insulating face 14.
[0019]
【The invention's effect】
By adopting a structure embossed to give a click feeling to the PET film, which is the upper transparent electrode of EL, the present invention was implemented in comparison with the known example switch shown in FIG. 5 having a thickness of 0.6 mm. The example switch has a thickness of 0.375 mm, and can be reduced in thickness by 0.225 mm. Moreover, since EL which is a planar light emitter is used as a light emitting element, there is no uneven illumination. For this reason, it is possible to illuminate the switch surface uniformly.
[0020]
According to the present invention, it is possible to further reduce the size and weight of a small portable device.
[0021]
Furthermore, the click can be easily adjusted by the laminated insulating layer or spacer at the bottom.
[Brief description of the drawings]
FIG. 1 is a sectional view of a first embodiment of the present invention. FIG. 2 is a sectional view of a second embodiment of the present invention. FIG. 3 is a view showing a conventional self-illuminating tact switch. FIG. 5 is a diagram showing a conventional EL element illumination switch.
DESCRIPTION OF SYMBOLS 1 Display part 2 Adhesive 3 Transparent thermoplastic resin 4 Transparent electrode layer 5 Light emitting layer 6 Dielectric layer 7 Back surface electrode layer 8 Insulating layer 10 Upper contact part 11 Insulating layer 12 Lower substrate 13 Lower electrode 14 Insulating surface

Claims (3)

  In an illuminated switch composed of an electroluminescent element (hereinafter referred to as EL element), a transparent or translucent thermoplastic resin of the uppermost layer of the EL element and a transparent electrode layer of the next layer are embossed in a dome shape, and a click type spring part An insulating layer is arranged inside the resin dome, a contact portion is provided in the center, and other EL elements in the lower layer corresponding to the dome-shaped spring portion. An illuminated switch comprising a body layer, a back electrode layer, and a central portion of an insulating layer cut away. In an illuminated switch composed of an electroluminescence element (hereinafter referred to as EL element), a transparent or translucent thermoplastic resin on the uppermost layer of the EL element is embossed into a dome shape to form a click-type spring, and inside the resin dome A contact portion is provided on the inside of the transparent electrode layer, the light emitting layer, the dielectric layer, the back electrode layer, and the central portion of the insulating layer, which is another EL element in the lower layer corresponding to the dome-shaped spring portion. An illuminated switch, characterized in that the central cut end surface of the transparent electrode layer is an insulating surface.   3. The illumination type switch according to claim 1, wherein a display unit made of translucent rubber or thermoplastic resin is placed on the entire upper surface of the dome-shaped spring unit.

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