JPS60147718A - Color display element with solar battery - Google Patents

Abstract

PURPOSE:To improve the beauty in design and the degree of freedom thereof by providing a selective scattering layer which scatters the specific wavelength of visible light and allows the transmission of the light in a wavelength region contributing to generation of electricity on the front face of a solar battery and providing further a display element of transmission type on the front face thereof. CONSTITUTION:A selective scattering layer 2 which scatters the specific wavelength of visible light and allows transmission of at least part of the light in the wavelength region contributing to generation of electricity is provided on the front face of a solar battery 1. A display element 3 of a transmission type is further disposed on the front face thereof. A layer formed by dispersing a microcapsulated cholesteric liquid crystal in a binder or cholesteric polymer sheet or the like is used for the layer 2 or a dichroic mirror 4 and a diffusion transmission layer 5 are used by superposing the same. An EC display element may be used as the element 3 as well. Incident light is transmitted in the part where the driving voltage of such display element is not impressed. The blue light is scattered and reflected by the layer 2 and is emerged by passing through the liquid crystal. The light is shielded in the part where the voltage is impressed. The sharp black display on, for example, the blue ground is thus obtd. and the degree of freedom in design is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a color display element equipped with a solar cell.

Conventionally, solar cells have been put into practical use by being incorporated into watches and calculators. However, since the black or similar color of the solar cells was visible as is, it was not aesthetically pleasing and was not desirable in terms of design.

The present invention solves the above-mentioned conventional drawbacks by using the front side of the solar cell for color display.

Next, embodiments of the invention will be described.

In FIG. 1, a selective scattering layer 2 is provided on the front surface of a solar cell 1, and a transmission type display element 5 is further provided on the front surface thereof.

Amorphous silicon or single crystal silicon are currently in practical use as solar cells a1, and when these are used, the wavelengths that contribute to the power generation of the solar cells are as shown in the second figure. As the selective scattering layer 2, a layer formed by coating microcapsules of cholesteric liquid crystal dispersed in a binder, a cholesteric polymer sheet, or the like is used. This selective scattering layer 2 scatters light of a specific wavelength in the visible range and transmits residual light. Therefore, it is better to shift the scattered light from the wavelength that contributes to power generation by the solar cell 1.

The light of the wavelength selectively scattered by the selective scattering layer 2 is not completely blocked by the cholesteric liquid crystal, and nearly half of it is transmitted, so no power is generated even if selective scattering 1- of any color in the visible range is used. There isn't. However, it is better to shift it to improve power generation efficiency. For example, if a blue selective scattering layer 2 is used, its light transmittance will be curved iA in Figure 2.
It is indicated by.

Therefore, in this case, whether amorphous silicon or single crystal silicon is used for the solar cell 1, the power generation efficiency hardly decreases. As a transmission type display element 6, t
In addition to a clear nematic liquid crystal display element, a guest-host type liquid crystal display element, a transmission type electrochromic display element, etc. can be used. This transmission type display element 5
Display segment patterns such as characters and figures are formed on the screen. Now, we will explain the display effect in the case where a positive display type guest-host type liquid crystal display element mixed with a black dichroic dye is used as the transmission type display element 5, and a blue cholesteric polymer sheet is used as the selective scattering layer 2. Then, the incident light passes through the portion of the liquid crystal display element to which no driving voltage is applied, and the blue light is scattered and reflected by the selective scattering layer 2 and comes out through the liquid crystal again. Therefore, that part looks dark. The remaining light that passes through the selective scattering layer 2 contributes to power generation by the solar cell 1. On the other hand, the portion of the display segment to which the driving voltage of the liquid crystal display element is applied is blocked from light and appears black. The overall design is black on blue l111. The characters will be displayed.

In the above embodiment, a cholesteric liquid crystal is used as the selective scattering layer 2, but the selective scattering layer 2 is not limited to this. 2 As shown in figure 2, as a selective scattering layer 2, a dichroic mirror 4 and a diffuse transmission layer 5 are arranged at f:1 (a wet one is also possible. The dichroic mirror 4 reflects light of a specific wavelength in the nJ viewing range, and the remaining light is The diffuse transmission layer 5 may be made of glass or plastic whose surface is treated with plastic, or may be made of a transparent plate sprayed with a matte lacquer.The function of the selective scattering layer 2 in this case is as described above. It is the same 15jf as the example.

The above embodiment describes the case where one transparent display element 5 is provided corresponding to one solar cell 1, but in this case, a plurality of solar cells 1 are connected and the gap is colored the same as the solar cell. It is also possible to provide a selective scattering device of 7 m 2 and a transmission type display element 5 on top of the reduced area.

The solar cell-equipped color display element of the present invention having the above-mentioned configuration allows the solar cell to be hidden on the prefecture side of the display element, so that the aesthetic appearance is maintained, and when used in the display device of each building, there is a greater degree of freedom in design. is large.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an embodiment of the present invention, FIG. 2 is a graph showing the relative output of the solar cell and the transmittance of the selective scattering plate, and FIG.
The figure is a sectional view of another embodiment. DESCRIPTION OF SYMBOLS 1...Solar cell, 2...Selective scattering layer, 5...Transmissive display element, 4...Dichroic mirror, 5...Diffused transmission layer. Applicant Seikosha Co., Ltd. Patent Attorney Mogami

Claims (4)

[Claims] (1) Scatter specific wavelengths of visible light on the front of the solar cell,
and a solar cell comprising a selective scattering layer that transmits at least a part of the light in the wavelength range that contributes to power generation in the solar pond, and further comprising a transmission type display element provided in front of the selective scattering layer. Color display element. (2) The solar cell H color display element according to claim 1, wherein the selective scattering layer comprises a layer in which one cell of a cholesteric liquid crystal microphone is dispersed in a binder and coated thereon, or a cholesteric polymer sheet. (3) The color display element with a solar cell according to claim 1, wherein the selective scattering layer is formed by superimposing a diffuse transmission layer on a dichroic ink mirror. (4) The color display element with a solar cell according to claim 1, wherein the transmission type display element is a liquid crystal display element or an electrochromic display element.