JP2012004485A - Light emission system using luminous material and portable device equipped with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light emission system capable of emitting light after light emission from a light source ended even if the time for exposure to external light is not enough, and to provide a portable device equipped with the same.SOLUTION: The light emission system comprises a luminescent layer 3 containing a luminous material that emit light by ultraviolet light and a light source 1 that irradiates the luminescent layer with the ultraviolet light. This system may further include a coloring layer 4 having permeability above the luminescent layer 3. The portable device comprises the luminescent layer 3 on its surface and the light source 1 inside it.

Description

  The present invention relates to a light emitting system using a phosphorescent material and a portable device including the same, and more particularly to a light emitting system used for an exterior of an electronic device and a portable device including the same.

  In recent years, electronic devices such as mobile phones are increasingly equipped with an illumination function for the purpose of enhancement of functions and designs. For example, Patent Document 1 discloses a technique related to a lighting device that is miniaturized in order to shine a part of the exterior of a mobile device and improve the decoration effect.

JP 2008-011356 A

  However, when trying to achieve illumination that appeals to users, power consumption tends to increase due to an increase in the number of light sources mounted and an increase in the amount of emitted light. In order to suppress this power consumption, it is possible to use a phosphorescent material for the exterior of an electronic device. Thereby, even if it does not light-emit illumination, the exterior part of an electronic device can be light-emitted using a luminous material. As a result, it can be expected that appeal of light emission to the user can be performed with less power consumption.

  However, when using a phosphorescent material as described above, the following problems exist. In order to sufficiently realize the light emission by the phosphorescent material, it is necessary to expose to external light including ultraviolet light for a certain period of time. Therefore, when a phosphorescent material is adopted for the exterior of an electronic device, particularly a device that has little opportunity to be exposed to external light, usage scenes that exhibit the effect of the phosphorescent material are limited.

  The present invention has been made to solve such problems, and includes a light emitting system capable of emitting light after the light emission of the light source is completed even when the exposure time to the external light is insufficient. An object is to provide a portable device.

The light emitting system according to the present invention includes a light emitting layer containing a phosphorescent material that emits light by ultraviolet light, and a light source that irradiates the light emitting layer with ultraviolet light.
Moreover, the portable apparatus concerning this invention is equipped with the said light emitting layer and a colored layer on the surface of a portable apparatus, and is equipped with the said light source inside the said portable apparatus.

  According to the present invention, it is possible to provide a light emitting system capable of emitting light after the light emission of the light source is completed and a portable device including the light emitting system even when the exposure time to external light is insufficient.

It is sectional drawing which shows the light emission system concerning Embodiment 1. FIG. In the light emission system concerning Embodiment 1, it is sectional drawing which shows the state immediately after having light-emitted and light-extinguishing after that. It is a top view of the mobile telephone provided with the light emission system concerning Embodiment 2. FIG. It is sectional drawing of the illumination part 21 of the mobile telephone provided with the light emission system concerning Embodiment 2. FIG. In a mobile phone provided with the light emission system concerning Embodiment 2, it is sectional drawing which shows the state immediately after having light-emitted and light-extinguishing after that. FIG. 6 is a cross-sectional view illustrating a case where a side view type light source is used in a mobile phone including the light emitting system according to the second embodiment. In Embodiment 2, it is sectional drawing for demonstrating the case where a multiple types of light source is used. In Embodiment 2, it is sectional drawing for demonstrating the case where a multiple types of light source and phosphorescent material are used. In Embodiment 2, it is sectional drawing for demonstrating the case where a fluorescent substance is newly used.

Embodiment 1
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view illustrating the light emitting system according to the first embodiment. The light emitting system using the phosphorescent material shown in FIG. 1 includes a light source 1 and a light emitting layer 3. The light source 1 may be any light source that emits ultraviolet light, such as an LED (Light Emitting Diode) or black light that emits ultraviolet light. The light emitting layer 3 that receives light from the light source 1 is made of a resin material containing a phosphorescent material. This phosphorescent material may be any material as long as it absorbs ultraviolet light emitted from the light source 1 and accumulates light, such as strontium aluminate, calcium aluminate, and zinc sulfide. The luminescent color of the phosphorescent material can be selected as appropriate, such as green or blue. The resin may be any material as long as it is a material suitable for processing by including a phosphorescent material such as ABS (Acrylonitrile Butadiene Styrene) resin or polycarbonate resin. The direction of light emission from the light source 1 is indicated by reference numeral 10. The light source 1 and the light emitting layer 3 are configured to be provided in an arbitrary electronic device (not shown in the drawings) such as an information device and a portable terminal. In the appearance of this electronic device, the light emitting layer 3 is provided outside the light source 1.

  Now, in the first embodiment of the present invention shown in FIG. 1, the light source 1 emits light. Then, ultraviolet light is emitted in the direction 10 from the light source 1, and the phosphorescent material of the light emitting layer 3 stores the light by receiving the ultraviolet light. FIG. 2 shows a state immediately after the light source 1 is caused to emit light and then turned off. The hatched portion in FIG. 2 indicates that the portion of the light emitting layer 3 that has been stored when the light source 1 emits light emits light. As described above, by using a light source that emits ultraviolet light as the light source 1 mounted in the present invention, it is possible to store the phosphorescent material simultaneously with the light emission of the light source. As a result, by using the present invention, it is possible to provide a light emitting system using a phosphorescent material capable of emitting light after the light emission of the light source is completed even when the exposure time to outside light is insufficient. .

Embodiment 2
Next, a second embodiment of the present invention will be described. FIG. 3 is a top view of the mobile phone 20 having the light emitting system according to the second embodiment. Here, the light emitting system provided in the mobile phone 20 is provided in the illumination unit 21 of the mobile phone. The illumination unit 21 performs operations such as light emission in accordance with processing such as incoming call / mail reception of a mobile phone. Further, the entire back surface of the mobile phone is a single decorative panel, and this panel is produced by two-color molding. Thereby, a panel having a two-layer structure including the light emitting layer 3 and the colored layer 4 (described later) can be realized.

  FIG. 4 shows a cross-sectional view of the configuration of the illumination unit 21 shown in FIG. The illumination unit 21 includes a light source 1 and a panel 2. The panel 2 further includes a light emitting layer 3 containing a phosphorescent material and a colored layer 4. Here, the downward direction in FIG. 4 indicates the inside of the mobile phone 20 (not shown in FIG. 4), and the upward direction indicates the surface side of the mobile phone 20. The light source 1 in FIG. 4 is an LED that emits ultraviolet light. As described with reference to FIG. 1, the light source 1 may be any light source that emits ultraviolet light. However, since the light source 1 is required to be small for use in a mobile phone, it emits ultraviolet light here. LED. The material used for the LED that emits ultraviolet light is, for example, gallium nitride or indium gallium nitride, but any material that emits ultraviolet light may be used. The wavelength of the ultraviolet light emitted from the light source can be any wavelength such as UV-A or UV-B as long as it is in a band that is absorbed by the phosphorescent material used in the light emitting layer 3. The light source 1 is provided inside the mobile phone 20.

  Moreover, the light emitting layer 3 containing the luminous material of FIG. 4 is comprised with the resin material containing a luminous material like the above. The colored layer 4 is a resin material designed to have transparency. The resin material may be any material as long as it is permeable and can be processed, such as acrylic resin and polycarbonate resin. The reason why the colored layer 4 is provided in the second embodiment is that, when the luminous layer 3 is made of a luminous material that emphasizes the amount of emitted light and the colored layer 4 is not provided, the color tone of the luminous material when not emitting light is limited. This is because the design of the appearance of the mobile phone 20 becomes poor. Therefore, the colored layer 4 is accented with color variations to improve the design. Further, in the colored layer 4, not only coloring but also sparse materials such as glass powder and pearl powder can be kneaded to improve the design. The light emitting layer 3 and the colored layer 4 have a two-layer structure and constitute the surface of the mobile phone 20. Note that a direction 10 indicated by an arrow in FIG. 3 is a light emission direction of the light source 1, and ultraviolet light is irradiated from the inside of the mobile phone 20 toward the surface.

  Now, let it be assumed that the light source 1 emits light in the illumination unit 21 shown in FIG. FIG. 5 is a diagram showing a state immediately after the lights are turned off. The hatched portion in FIG. 5 indicates that the portion of the light emitting layer 3 that is stored when the light source 1 emits light emits light, as in FIG. Further, by providing the colored layer 4, the appeal of light emission when the phosphorescent material emits light can be increased as compared with the case where the colored layer 4 is not provided.

  As described above, according to the present embodiment, a phosphorescent material of a light emitting system can be made to emit light without depending on external light in an external part of an electronic device having an illumination function. Thereby, the original light emitting function of the illumination of the electronic device can be assisted and a power saving effect can be obtained. This is because even if the light source does not emit light, the illumination effect is generated by the light emission by the phosphorescent material. In addition, it is possible to improve the function of the device such that the location of the electronic device is known by the fact that the phosphorescent material shines in a dark place. Furthermore, the structure having the colored layer 4 can solve the problem of design restrictions on the appearance of the light emitting system, which can occur when a phosphorescent material is used. Further, regarding the light emission effect on the user, not only the light emission by the phosphorescent material after the LED is turned off, but also the user can be provided with a specific color when the phosphorescent material is irradiated by the ultraviolet light emitting LED.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention. For example, the exterior of the illumination part 21 has a two-layer structure of the light emitting layer 3 and the colored layer 4, but may have a structure of three or more layers. In that case, two or more light emitting layers containing different phosphorescent materials may be provided, or two or more different colored layers may be provided. In the description of the second embodiment, the light emitting layer 3 and the colored layer 4 are formed by two-color molding, but may be manufactured by any other injection molding method. Further, the bonding method of each layer such as the light emitting layer or the colored layer is not limited to bonding by multilayer molding, and may be bonded using an adhesive in post-processing. Alternatively, the light emitting layer and the colored layer may be formed by cutting a plate-like resin having a multilayer structure. Although the degree of freedom in design is narrowed, the colored layer 4 may be a coating film of paint or ink, and may be adhered to the surface of the light emitting layer 3 by painting or printing. Further, although the effect of light emission is reduced, the light emitting layer 3 may be a coating film in which a phosphorescent material is kneaded with paint or ink, and may be adhered to the back surface of the colored layer 4 by painting or printing. In any case, it is sufficient for the light emitting system to have a structure in which light emitted from the light emitting layer including the phosphorescent material is transmitted through the surface of the mobile phone and a sufficient amount of light enters the eyes of the user.

  Further, as a coloring method of the colored layer 4, half vapor deposition may be performed. This is a process of applying a transparent metal thin film to the surface of the colored layer 4. Thereby, when the light emitting layer 3 is not emitting light, the appearance design of the mobile phone 20 is enhanced. In addition, when the light emitting layer 3 emits light, the user can see the light emitted from the phosphorescent material through the metal thin film, thereby enhancing the appeal of the light emission. As the metal used for the thin film, one kind or two or more kinds of metals such as aluminum, tin, and chromium, metal compounds, or metal alloys may be used. Any metal suitable for half vapor deposition that maintains the transparency of the colored layer 4 is sufficient. The material of the colored layer 4 is not limited to resin, and may be transparent glass. Further, the resin or glass material that is the material of the colored layer 4 is not completely transparent, but may be colored as long as it has transparency.

  In the second embodiment, the present invention is implemented using the light emitting layer 3 and the colored layer 4 including the phosphorescent material as parts of the decorative panel. However, the present invention may be implemented in the casing of the electronic device itself. For example, the light source 1 is built in the electronic device, and the light emitting layer 3 and the colored layer 4 form the surface of the entire housing of the electronic device. Furthermore, as shown in FIG. 6, a side view type LED may be used, and the light emitting layer 3 and the colored layer 4 may be irradiated with ultraviolet light in the cross-sectional direction 11. In addition, the light emitting system of Embodiments 1 and 2 can be applied not only to a mobile phone but also to other portable electronic devices such as a portable music player and a notebook computer.

  Furthermore, the expression pattern of illumination may be increased by using a plurality of LEDs. For example, in FIG. 4, the light source 1 only describes LEDs that emit ultraviolet light, but may be configured to include LEDs having a function of emitting visible light such as red, green, and blue. FIG. 7 is a diagram showing Embodiment 2 of the present invention in such a case. The light source 1-1 is an LED that emits ultraviolet light, and the light source 1-2 is an LED that emits red light. A panel 2 is provided above the light sources 1-1 and 1-2. Moreover, the panel 2 is provided with the light emitting layer 3 and the colored layer 4 containing a luminous material similarly to the case of FIG. Description of the cellular phone equipped with this light emitting system is omitted as in FIG. In FIG. 7, it is assumed that the light source 1-1 and the light source 1-2 are made to emit light simultaneously. In that case, the light emitting layer 3 absorbs the ultraviolet light emitted from the light source 1-1 to store the light. On the other hand, red light emitted from the light source 1-2 passes through the light emitting layer 3 and the colored layer 4 and enters the user's eyes. Thereafter, when the light sources 1-1 and 1-2 are turned off, the stored light emitting layer 3 emits light. From this configuration, the light source 1-2 emits visible light until the ultraviolet light source 1-1 emits light and the light emitting layer 3 receiving the light emits light. Appeal can be increased.

  In this case, since the light emitted from the light source 1-2 is required to pass through the light emitting layer 3 and the colored layer 4 and enter the user's eyes, the light emitting layer 3 is thin enough to satisfy the condition, or is not transmissive. What you have is desirable. The light emission color of the light source 1-2 is red in the example of FIG. 7, but other visible light such as green, blue, and white may be used. Moreover, the color which the light emitting layer 3 accumulates and emits light may be the same as the emission color of the light source 1-2, or may be different. The ultraviolet light emitting LED and the visible light emitting LED may be configured to include a plurality of types or a plurality of types or a plurality of types of LEDs. Further, as long as the LED emits visible light and emits ultraviolet light at the same time, the light source may be composed of only the LED. Of course, other types of light sources may be used instead of LEDs.

  As another example, a light emitting system including an ultraviolet light emitting light source having different wavelength peaks and a phosphorescent material having different excitation wavelength peaks is also conceivable. FIG. 8 is a diagram showing an example of the second embodiment in that case. Here, the light source 1-1 is an LED that emits ultraviolet light having a wavelength peak of A, and the light source 1-2 is an LED that emits ultraviolet light called B, which has a wavelength peak different from A. Here, A and B are wavelengths such as 370 nm and 330 nm, for example. The values A and B are arbitrary, but it is desirable that the wavelengths are separated to some extent as will be described later. The light emitting layers 3-1 and 3-2 also include different types of phosphorescent materials. Here, it is assumed that the excitation wavelength peak of the phosphorescent material included in the light emitting layer 3-1 is near 370 nm, and the excitation wavelength peak of the phosphorescent material included in the light emitting layer 3-2 is near 330 nm. In addition, it is assumed that the phosphorescent material included in the light emitting layer 3-1 emits green light by phosphorescence, and the phosphorescent material included in the light emitting layer 3-2 emits blue light by phosphorescence. Furthermore, it is assumed that there is no extreme difference in the emission intensity at the peak of the excitation wavelength between the light emitting layer 3-1 and the light emitting layer 3-2. The panel 12 in the light emitting system of FIG. 8 includes the light emitting layers 3-1 and 3-2 and the colored layer 4.

  Now, in the light emitting system of FIG. 8, it is assumed that only the light source 1-1 is caused to emit light and then turned off. In this case, the ultraviolet light emitted from the light source 1-1 excites the phosphorescent material in the light emitting layer 3-1 more strongly than the phosphorescent material in the light emitting layer 3-2. It shines stronger than phosphorescence by -2. Thereby, the light emission system of FIG. 8 mainly emits green light. Conversely, assume that only the light source 1-2 is turned on and turned off in the light emitting system of FIG. In this case, since the ultraviolet light emitted from the light source 1-2 excites the light emitting layer 3-2 more strongly than the light emitting layer 3-1, the light emitting layer 3-2 is stronger than the light emitting layer 3-1, due to light storage. Shine. Thereby, the light emission system of FIG. 8 mainly emits blue light. In this way, the light emitted from the light emitting layer 3-1 and the light emitting layer 3-2 can be changed by causing the light source 1-1 and the light source 1-2 to emit light alternately. You can turn it on.

  As described above, the light emission pattern of the light emitting system can be changed by using the light emitting system including the ultraviolet light emitting light source having the different wavelength peak and the phosphorescent material having the different excitation wavelength peak. Here, the excitation wavelength peak of the phosphorescent material in the light emitting layer 3-1 is substantially the same as the wavelength peak of the light source 1-1, and the excitation wavelength peak of the phosphorescent material in the light emitting layer 3-2 is the light source 1-2. If it is almost the same as the wavelength peak, the light emission by the phosphorescent material becomes so strong that the effect of appealing the light emission can be enhanced. (The excitation wavelength peak of the phosphorescent material in the light emitting layer 3-1 is substantially the same as the wavelength peak of the light source 1-2, and the excitation wavelength peak of the phosphorescent material in the light emitting layer 3-2 is the wavelength peak of the light source 1-1. (Although it may be almost the same.) Also, when the difference in the wavelength peak of the light source or phosphorescent material is small, even if the light source of different ultraviolet light emission is turned on, the difference in how the phosphorescent material shines cannot be obtained. Is assumed. For example, the wavelength peak of the light source 1-1 is 370 nm, and the wavelength peak of the light source 1-2 is 365 nm. In that case, the light emission of the phosphorescent material in the light emitting layers 3-1 and 3-2 is significantly changed between the case where only the light source 1-1 is emitted and the case where only the light source 1-2 is emitted. It is assumed that it is difficult to obtain. That is, the expression pattern of light emission becomes poor. The same situation is assumed when the excitation wavelength peak of the phosphorescent material 3-1 is 370 nm and the excitation wavelength peak of the phosphorescent material 3-2 is 365 nm. Therefore, as described above, it is desirable that the wavelength peaks of the light source and the phosphorescent material are separated to some extent. This is because variations in light emission can be added.

  The light source 1-1 and the light source 1-2 are not turned on, but both are turned on, and the light irradiation material 3-1 and the light storage material are adjusted by adjusting the irradiation amount of each light. The light emission amount of 3-2 may be adjusted to increase the expression pattern of light emission. In FIG. 8, two kinds of ultraviolet light emitting LEDs and a phosphorescent material are used, but a light emitting system having three or more kinds of ultraviolet light emitting LEDs and / or a phosphorescent material may be used.

  Furthermore, in Embodiment 2, a phosphor or the like that emits visible light in response to ultraviolet light may be newly included in the panel. The phosphor is, for example, a substance such as a europium complex, a samarium-doped phosphor, or a so-called RGB (Red Green Blue) phosphor, and can be arbitrarily selected according to the color of emitted light. FIG. 9 is a diagram showing an example of such a second embodiment. The light emitting system of FIG. 9 includes a light source 1 that emits ultraviolet light and a panel 12. The panel 12 further includes a phosphor layer 5 containing a phosphor together with a light emitting layer 3 containing a phosphorescent material and a colored layer 4 having transparency. Here, it is assumed that the fluorescent layer 5 contains a phosphor that receives ultraviolet light and glows white. Similarly to the light emitting layer 3, the fluorescent layer 5 is made of a resin material. Now, when the light source 1 is caused to emit light in FIG. 9, the fluorescent layer 5 emits white light by receiving ultraviolet light. Thereafter, when the light source 1 is turned off, the light emitting layer 3 emits light by storing light with ultraviolet light. In this way, by causing the phosphor to emit light in the light emitting system, variations in light emission can be increased and the appeal of light emission can be enhanced. The fluorescent layer is not limited to one type, and a plurality of types may be used for the panel. Moreover, you may include the fluorescent substance in which the peak wavelength in LED which light-emits ultraviolet light is near, and the peak of an excitation wavelength are near. Thereby, the light condition of the fluorescent layer 5 when ultraviolet light is emitted from the light source 1 can be increased. Further, although the light emitting layer 3 and the fluorescent layer 5 are shown separately in FIG. 9, the phosphor is included in the light emitting layer 3 so that the light emitting layer 3 and the fluorescent layer 5 are the same layer. It doesn't matter.

  As described above, in the light source of the light emitting system according to the second embodiment, a plurality of light sources that emit ultraviolet light having different wavelengths or a combination of a plurality of light sources that emit ultraviolet light and visible light has been described. Regarding the light-emitting layer, a plurality of phosphorescent materials having different excitation wavelength peaks, a plurality of phosphorescent materials that perform different color development, and a combination of phosphorescent materials and phosphors have been described. By appropriately combining these light sources and phosphorescent materials, a light emitting system that makes color appeal may be made. In short, a light emitting system that includes a light source that emits ultraviolet light and has a light emitting layer that receives and stores the emitted light is sufficient.

1, 1-1, 1-2 Light source 2, 12 Panel 3, 3-1, 3-2 Light emitting layer 4 Colored layer 5 Fluorescent layer 10 Direction of light emission 1
11 Direction of light emission 2
20 Mobile phone 21 Illumination part

Claims (10)

A light-emitting layer containing a phosphorescent material that emits ultraviolet light;
A light source for irradiating the light emitting layer with ultraviolet light;
A light emitting system comprising: The light emitting layer further includes a colored layer having transparency on the side opposite to the side where the light source is provided.
The light emitting system according to claim 1. The colored layer includes a glossy material;
The light emitting system according to claim 2. The light emitting layer and the colored layer are molded by resin injection molding,
The light emitting system according to claim 2 or 3. The light emitting layer and the colored layer are formed by cutting a plate-shaped resin having a multilayer structure.
The light emitting system according to claim 2 or 3. The light emitting layer is made of a resin, and the colored layer is made of a glass material.
The light emitting system according to claim 2 or 3. The light emitting layer includes a first phosphorescent material having a first excitation wavelength peak, and a second phosphorescent material having a second excitation wavelength peak,
The light source emits light having a peak having substantially the same wavelength as the first excitation wavelength peak, and light having a peak having substantially the same wavelength as the second excitation wavelength peak. Two light sources,
Adjusting the amount of light emitted from the first light source and the amount of light emitted from the second light source to adjust the amount of light emitted from the first and second phosphorescent materials;
The light emitting system according to any one of claims 1 to 6. The light source further comprises a light source that emits visible light,
The light emitting system according to any one of claims 1 to 7. The light emitting layer further includes a phosphor that emits ultraviolet light.
The light emitting system according to any one of claims 1 to 8. A portable device comprising the light emitting system according to any one of claims 1 to 9,
The light emitting layer is provided on the surface of the portable device,
A portable device comprising the light source inside the portable device.

Images