JP2011113017A - Optical structure and optical display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical structure having a design pattern which is visible in a default state that does not use backlight, wherein the design pattern does not interfere with viewing of a design pattern appearing with the backlight, and to provide an optical display device. <P>SOLUTION: The optical structure is constituted of mask layers 26a, 26b, which are composed of a plurality of thin film layers of an optical film, and out of which a first design pattern is made hollow; a shielding layer 24, disposed on the upper side of the mask layers 26a, 26b, provided with absorbency, to make the intensity of the first design pattern of the mask layers be at a level which cannot be seen through with an external light, and provided with a predetermined transmittance, to make irradiating light irradiating from the rear side thereof pass through the hollowed section of the mask layers 26a, 26b and be transmitted therethrough. With a reflection layer 23 disposed on the upper side of the shielding layer 24 provided with a predetermined reflectance to reflect the external light and is provided with transmittance for transmitting the irradiating light and with a second design pattern made hollow, the transmittance in the reflection layer is set larger than the reflectance therein. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical structure that includes a plurality of thin film layers and displays characters with a design pattern removed by irradiating light from behind, and an optical display device including such an optical structure.

Conventionally, for example, characters, symbols or figures are printed on the press surface of an input key which is an input means such as a mobile phone or a personal computer, and this is executed when the input key is pressed by recognizing the characters. The input contents are understood. For example, in a mobile phone, a numeric keypad on which numbers are printed is basically a key for inputting a telephone number. When the numeric keypad on which the numbers are printed is pressed, the number is input as a telephone number. Patent document 1 is given as an example of such a mobile phone.
By the way, in recent years, mobile phones have been required to diversify their designs and functions. In addition to mobile phones with a general vertical design such as the mobile phone of the cited reference 1, a mobile phone with a landscape design that has a landscape orientation has been developed. Demand is also being recognized. This is because, for example, in a so-called one-seg type mobile phone in which a large liquid crystal panel with a built-in one-seg tuner is provided, it may be convenient to use the input key sideways. The same situation exists in other electronic devices such as PDAs (Personal Digital Assistants) other than mobile phones.
Furthermore, there is also a demand to use both the vertical and horizontal orientations at any time on the same model depending on the situation. For example, the one-seg type mobile phone as described above is used in a portrait orientation when used as a mobile phone, and is used in a landscape orientation when viewing an image.

However, if you want to use both the vertical and horizontal orientations on the same model at any time, use the characters printed on the input keys etc. Characters will fall asleep (tilt at 90 degrees), making them very difficult to read. For this reason, it may be possible to print two characters or the like that are oriented 90 degrees adjacent to each other, but the screen feels dusty and is not preferable in terms of design.
In order to solve such a problem, it is conceivable to arrange two design patterns such as characters having different 90-degree orientations at the same position by using two different thin film layers. Then, only one of the design patterns is clearly raised using the backlights as two types of visible light sources having different wavelengths. However, when the two design patterns are arranged so as to intersect with each other, when the backlight is not turned on (hereinafter, this case is assumed to be the default state), both design patterns 201 and 202 (in this example, as shown in FIG. 6) Will be viewed in a state of being mixed in a color tone opposite to that of the backlight. As a result, it becomes difficult to distinguish characters and the like, and the appearance of the keys becomes poor.
Therefore, the applicant proposed the optical structure of Patent Document 2 on December 28, 2006. In patent document 2, the design pattern of the part which matched in the default state by using three dielectric thin film layers, and making the design pattern of the uppermost dielectric thin film layer correspond with the design pattern of one of the lower layer thin film layers. Is to make it invisible.

JP 2002-1111836 (FIG. 2) JP 2008-164877 A

However, the above-mentioned Patent Document 2 has a configuration in which a design pattern that is crossed in a default state is visually observed, and there is a demand for visualizing a design pattern that is different from the design pattern that appears in the backlight in the default state. However, since the thin film layer of such a new design pattern is arranged in the viewing direction, that is, the uppermost layer, when the backlight is turned on, it obstructs the viewing of the design pattern that appears in the backlight. There is a possibility.
The present invention has been made paying attention to such problems existing in the prior art. The purpose is to have a design pattern that is visible in a default state that does not use a backlight different from the design pattern that appears in the backlight, and that the different design pattern does not interfere with the visual inspection of the design pattern that appears in the backlight. An optical structure and an optical display device are provided.

As a first means for solving the above problems, in the optical structure formed by laminating a plurality of thin film layers on one or a plurality of transparent substrates, the plurality of thin film layers include characters, A mask layer in which a first design pattern made up of symbols, figures, or the like is hollowed out so as to have either a negative or positive relationship, and is disposed in an upper layer of the mask layer, and the first layer of the mask layer is formed by external light. Provided with a predetermined absorptivity for obtaining a density at which the design pattern cannot be seen through, or a reflectance for reflecting the external light to a degree that cannot be seen through, and is irradiated from behind the hollow portion of the mask layer. A shielding layer having a predetermined transmittance for transmitting the irradiation light; and a predetermined transmittance for transmitting the irradiation light while being disposed on an upper layer of the shielding layer and having a predetermined reflectance for reflecting the external light. And a reflective layer in which the second design pattern made up of letters, symbols, figures, etc. is hollowed out so as to have either a negative or positive relationship, and the transmittance in the reflective layer is larger than the reflectance The gist is that it has been set.
As a second means, a visible light source for irradiating visible light of a predetermined wavelength to the optical display device, and a first design pattern made up of characters, symbols, figures, etc. arranged in front of the visible light source A mask layer that is hollowed out so as to have either a negative or positive relationship, and an upper layer of the mask layer for obtaining a density at which the first design pattern of the mask layer cannot be seen through by external light. Predetermined transmission that has a predetermined absorption rate or a reflectance that reflects the outside light to the extent that it cannot be seen through, and that transmits the irradiation light irradiated from the visible light source behind the mask layer through the hollow portion A letter, a symbol or a letter having a predetermined transmittance for transmitting the irradiation light, and having a predetermined reflectance for reflecting the outside light, and a shielding layer having a ratio and an upper layer of the shielding layer The gist is that the second design pattern having a shape or the like is composed of a reflection layer in which the transmittance is set so that the negative or positive relationship is set larger than the reflectance. .

As a third means, in the optical structure formed by laminating a plurality of thin film layers on one or a plurality of transparent substrates, the plurality of thin film layers are formed from characters, symbols, figures, or the like. A mask layer in which the first design pattern is hollowed out so as to have either a negative or positive relationship, and a predetermined reflectance for reflecting external light, which is disposed in an upper layer of the mask layer, and the irradiation A reflective layer in which a second design pattern made up of characters, symbols or figures having a predetermined transmittance for transmitting light is hollowed out so as to have either a negative or positive relationship, and an upper layer of the reflective layer A predetermined absorptivity for obtaining a density at which the first design pattern of the mask layer cannot be seen through by the outside light, or a reflectance that reflects the outside light to a degree that cannot be seen through. A shielding layer having a predetermined transmittance capable of transmitting illumination light emitted from behind through the vent portion in the reflected light and the mask layer of the reflective layer,
The gist is that the transmittance in the reflective layer is set larger than the reflectance.
Further, as a fourth means, a first design pattern consisting of a visible light source that emits visible light of a predetermined wavelength and characters, symbols, figures, etc. arranged in front of the visible light source is negative or positive. The mask layer hollowed out so as to be in any relationship and the upper layer of the mask layer is provided with a predetermined reflectance for reflecting external light and a predetermined transmittance for transmitting the irradiation light. The second design pattern consisting of letters, symbols, figures, etc. is placed in the reflective layer with the transmittance set to be larger than the reflectance so that the negative or positive relationship will be in either negative or positive relationship, and on the upper layer of the reflective layer And having a predetermined absorptance for obtaining a density at which the first design pattern of the mask layer cannot be seen through by the outside light, or a reflectance for reflecting the outside light to a degree that cannot be seen through. The gist of the invention is that it is constituted by a shielding layer having a predetermined transmittance that transmits the reflected light of the reflective layer and the irradiation light irradiated from behind the mask layer. To do.

In order to facilitate the description of the configuration of the optical structure having such a configuration, an example of the structure is illustrated.
First, the first and second means will be described in the case where the shielding layer has a predetermined absorptance for obtaining a density at which the first design pattern of the mask layer cannot be seen through by external light.
For example, a laminated structure of three dielectric thin film layers 101 to 103 as shown in FIGS. 7 and 8 can be assumed. Although the film is formed on one transparent substrate 104 here, the film may be formed on a plurality of transparent substrates 104 and stacked to form a three-layer structure. Further, as will be described later, the mask layer may be composed of a plurality of layers. However, in order to simplify the description, the mask layer will be described as one layer below.
In the mask layer 101, the first design pattern made up of characters, symbols, figures, or the like is hollowed out so as to have either a negative or positive relationship. Here, the “relation between negative or positive” means that either a case where the character portion is hollowed out or a case where a thin film layer is formed only in the character portion and the periphery thereof is omitted.
The shielding layer 102 is disposed on the upper layer of the mask layer 101, that is, on the outside light side. The shielding layer 102 absorbs external light and has a predetermined absorptivity (transmittance) at a concentration that shields the mask layer 101 to such an extent that the first design pattern of the mask layer 101 is not understood as a film body having a predetermined concentration. I have. All visible light may have an equal absorptance, and there may be a case where only a certain wavelength is specifically absorbed and the other is reflected. That is, the shielding layer 102 may have both absorption and reflection characteristics with respect to visible light.
On the other hand, the shielding layer 102 has a predetermined transmittance so as to transmit the irradiation light emitted from the visible light source behind.
The reflective layer 103 is disposed on the upper layer of the shielding layer. In the reflective layer 103, the second design pattern made up of characters, symbols, figures, etc. is hollowed out so as to have either a negative or positive relationship. Although it is basically assumed that the first design pattern is different from the first design pattern, this does not prevent the use of the same design pattern as the first design pattern. The reflective layer 103 has a predetermined transmittance that transmits the irradiation light emitted from the visible light source behind.

In such an optical structure, the behavior of external light and irradiation light when the visible light source is turned on and when the visible light source is turned off (default state) will be described. First, a case where the visible light source is turned on will be described.
As shown in FIG. 7, when the irradiation light L1 is irradiated from the visible light source B on the mask layer 101 side, the irradiation light L1 is shielded by the mask layer 101 and is a thin film layer according to a portion other than the mask layer 101, that is, the first design pattern. Pass through the part without the mark. Further, the irradiation light L1 passes through the shielding layer 102, reaches the reflection layer 103, passes through the reflection layer 103, passes through the portion without the thin film layer, and reaches the front surface.
As a result, the first design pattern of the mask layer 101 illuminated by the irradiation light is viewed from the front.
Next, a case where the visible light source is turned off will be described.
As shown in FIG. 8, the external light L <b> 2 is reflected by the reflective layer 103 and is visually observed according to the second design pattern of the reflective layer 103. On the other hand, the portion of the reflective layer 103 without the thin film layer is the shielding layer 102, and the outside light L2 is absorbed here and becomes a predetermined concentration to shield the mask layer 101 and serve as the background of the reflective layer 103.
As a result, the second design pattern of the reflective layer 103 illuminated by the external light L2 is viewed from the front with the shielding layer 102 in the background.

  Here, in an environment where the optical structure is used, a state in which the external light L2 exists is common even when the irradiation light L1 is irradiated. Since it is desired to make the first design pattern visible when the irradiation light L1 is irradiated, it is preferable that the second design pattern is not visually observed. However, as shown in FIG. 7, when the external light L2 is present, the pattern to be visually observed always includes the second design pattern. Therefore, in the present invention, the transmittance is set to be larger than the reflectance of the reflective layer 103 so that more irradiation light from the visible light source enters the eye.

Next, the case where the shielding layer has a reflectance that reflects external light to such an extent that the first design pattern of the mask layer cannot be seen through by external light will be described. 9 and 10 are images when the shielding layer reflects external light.
In this case as well, the shielding layer basically does not differ greatly from the case of absorbing external light as described above, and when the visible light source is turned on, the irradiation light L1 passes through the shielding layer 102 and the reflection layer. At 103, the reflective layer 103 is transmitted, and passes through the portion without the thin film layer to reach the front surface. As a result, the first design pattern of the mask layer 101 illuminated by the irradiation light is viewed from the front. On the other hand, when the visible light source is turned off, the external light L2 is reflected by the reflective layer 103 and is visually observed according to the second design pattern of the reflective layer 103. However, the second design pattern of the reflective layer 103 illuminated by the external light L2 is white when it has a mirror surface or irregular reflection, unlike the case of absorption when the reflectance for reflecting external light is provided. Will be visually recognized from the front side due to the difference in reflectance with such a shielding layer 102 as the background.
Moreover, it is possible to obtain desired reflected light by specifically reflecting all or a specific wavelength of visible light.
If some visible light is not reflected, it is absorbed or transmitted. As described above, the shielding layer may have both absorptance and reflectance at the same time. The transmission characteristics of the shielding layer can be adjusted by the amount of absorption and the amount of reflection. When the amount of absorption is increased, it becomes darker (blackened), and when the amount of reflection is increased, it can be mirrored (whited). That is why.

Next, the third and fourth means will be described. In the third and fourth means, the positions of the shielding layer and the reflection layer are reversed. FIG. 12 and FIG. 13 are the images. First, a case where the visible light source is turned on will be described.
As shown in FIG. 12, when the irradiation light L1 is irradiated from the visible light source B on the mask layer 101 side, the irradiation light L1 is shielded by the mask layer 101, and a portion other than the mask layer 101, that is, a thin film layer according to the first design pattern. Pass through the part without the mark. Further, the irradiation light L1 passes through the reflective layer 103, passes through the portion of the reflective layer 103 without the thin film layer as it is, and reaches the shielding layer 102. The transmitted irradiation light L1 reaches the shielding layer 102 and is transmitted therethrough and reaches the front surface.
As a result, the first design pattern of the mask layer 101 illuminated by the irradiation light is viewed from the front.
Next, a case where the visible light source is turned off will be described.
As shown in FIG. 13, the external light L <b> 2 that has passed through the shielding layer 102 is reflected by the reflective layer 103 and is visually observed according to the second design pattern of the reflective layer 103. Further, the external light L2 is absorbed by the shielding layer 102 and becomes a predetermined concentration to shield the mask layer 101.
As a result, the second design pattern of the reflective layer 103 illuminated by the external light L2 is viewed from the front with the shielding layer 102 in the background.
When the shielding layer 102 exhibits reflection characteristics instead of absorption, it can be considered as in the above paragraph 0011.

In the present invention, the mask layer is composed of a plurality of mask layers stacked adjacent to each other so that each mask layer does not specifically transmit irradiation light in a predetermined wavelength region, and each of the other masks. It is preferable to transmit irradiation light in a predetermined wavelength range that is not specifically transmitted by the layer. Here, “does not transmit” refers to the case where visible light in a predetermined wavelength range is absorbed or reflected, or has optical characteristics due to both actions.
If comprised in this way, it will become possible to illuminate a different design pattern by irradiating separately the irradiation light of a different wavelength range from the back with respect to several mask layers from which a transmission characteristic differs. For example, a plurality of mask layers are used as two first and second mask layers. The first mask layer does not specifically transmit irradiation light in a red wavelength region, and transmits visible light in other wavelength regions. It is assumed that the second mask layer does not specifically transmit the irradiation light in the blue wavelength region and transmits the visible light in other wavelength regions. Then, when the irradiation light in the red wavelength region is irradiated, only the first design pattern of the first mask layer is visually observed from the front, and when the irradiation light in the blue wavelength region is irradiated, the second mask layer. Only the first design pattern will be viewed from the front.
In the case of a plurality of mask layers, the shielding layer has an absorption characteristic corresponding to the combined optical characteristics of the multiple mask layers (in other words, transmission characteristics combining the respective optical characteristics). It is preferable to exhibit a transmission characteristic contrary to the above. As a result, the shielding layer and the plurality of mask layers are overlapped without significantly impairing the brightness of the blue illumination light pattern and the red illumination light pattern, and the absorption characteristics other than the wavelength region showing the transmission characteristics are improved. The layer becomes darker, and the visual effect of the reflective layer in the default state is improved.

The reflectance in the reflective layer is 4% or more and preferably less than 10%.
The reflectance is the amount of reflection including both regular reflection and diffuse reflection. If the reflectance is too high, the second design pattern will be visually observed even when the visible light source is turned on. is there. In general, the regular reflectance of one surface of a transparent substrate having a refractive index of about 1.5 is about 4%, so that a difference in reflectance with this transparent substrate is created. Therefore, the reflectance of the reflective layer must be 4% or more. However, the upper limit is preferably less than 10% experimentally. Therefore, when a reflective layer is formed on a transparent substrate having a high refractive index, the reflectance of the reflective layer is preferably less than 10%, and a reflectance that creates a difference with respect to the reflectance of the substrate is preferable.
Furthermore, the smaller the difference between the amount of light passing through the reflective layer and the amount of light passing through the portion other than the reflective layer, the better. Specifically, it varies depending on the amount of light transmitted through the shielding layer and the mask layer, but it is preferable to suppress the light amount difference within 10 times.

If the brightness of the irradiation light is twice or more that of the outside light, the reflective layer will not disturb the visual inspection of the design pattern.
Even if the visible light source is turned on when the amount of light that passes through the reflective layer, the shielding layer, and the mask layer does not increase with respect to the amount of light reflected by the reflective layer from outside light, the second design is used. Since the pattern is visually recognized, the visible light source to be illuminated needs to be brighter than the external light under the conditions after passing through the mask layer, the shielding layer, and the reflection layer.

Here, the thin film layer of the present invention is a film body having a thickness of several tens of nanometers to several hundreds of μm, the mask layer has a predetermined absorptance or reflectance, and the shielding layer has a predetermined absorptance and transmittance. The reflective layer has a predetermined absorptance and reflectance.
It is conceivable that the thin film layer is formed by a predetermined film formation method (printing, spin coating, dipping, coating, dyeing, etc.) in which fine particles are mainly dispersed in a binder resin. The binder resin is not particularly limited as long as it is substantially transparent and does not significantly change the irradiation light. Examples thereof include polyester, polycarbonate, urethane resin, acrylic resin, methacrylic resin, organic silicon resin, and fluorine resin. Specific examples of the fine particle material include pigments, dyes, and fluorescent agents.
Moreover, a thin film layer can also be comprised with a dielectric multilayer film. Generally, the dielectric thin film layer itself has a multilayer film structure. It is possible to freely control the transmitted light (that is, reflected light) by designing the number of dielectric thin films, the film material, and the film thickness. Each constituent film layer of the multilayer film is a film material made of metal, metal nitride, metal oxide, or metal fluoride. For example, Cr (chromium), Ni (nickel), Si (silicon), Si ₃ N ₄ ( Silicon nitride) TiO ₂ (titanium dioxide), Ta ₂ O ₅ (tantalum pentoxide), SiO ₂ (silicon oxide), MgF ₂ (magnesium fluoride), CaF ₂ (calcium fluoride), and the like.
In the present invention, the number of multilayer films constituted is not particularly limited. A dielectric optical film can be configured by selecting and combining compounds in order to exhibit reflection performance or transmission performance for a desired wavelength. The method for forming the dielectric thin film layer is not particularly limited, but it is generally preferable to form the film by a vapor deposition method or a sputtering method.
In addition to the film formation method described above, the reflective layer can have a reflectance by obtaining a structure on the material surface by physical treatment such as blast treatment or chemical treatment such as etching treatment.

The plastic substrate used in the present invention is not particularly limited. For example, glass, polycarbonate, polymethyl methacrylate and its copolymer, polypropylene, polyethylene, vinyl chloride, ABS resin, phenol resin, melamine resin, silicone Resin, NBR resin, AS resin, etc. are mentioned as an example.
The present invention can be applied to display screens of mobile devices, electronic devices such as PDAs (Personal Digital Assistants), radios, and the like.

  In the inventions of the above claims, the design pattern is visible in a default state that does not use a backlight that is different from the design pattern that floats on the backlight, and the design pattern that appears by the backlight is obstructed from visual observation. Therefore, the design pattern visible in the default state can be freely set, and the application range of the optical structure is further expanded.

(A) is a side view of a mobile phone according to an embodiment of the present invention. It is a front view of the same mobile phone, (a) is the case where the touch keys displayed on the touch panel are vertically oriented, (b) is the default state. Explanatory drawing explaining schematic structure of the touchscreen in the same mobile phone. (A)-(c) is a front view for demonstrating the pattern of each thin film layer. Explanatory drawing which illustrates typically the layer structure of the optical film of the same Example. Explanatory drawing explaining the example of the pattern displayed on the surface of the conventional touch panel when the backlight is not irradiated. Explanatory drawing which illustrates typically the absorption characteristic with respect to the external light and irradiation light of the optical structure of this invention. Explanatory drawing which illustrates typically the absorption characteristic with respect to the external light of the optical structure of this invention. Explanatory drawing which illustrates typically the reflection characteristic with respect to the external light and irradiation light of the optical structure of this invention. Explanatory drawing which illustrates typically the reflection characteristic with respect to the external light of the optical structure of this invention. Explanatory drawing which illustrates the layer structure of the optical film of Example 3 typically. Explanatory drawing which illustrates typically the absorption characteristic with respect to the external light and irradiation light of the optical structure of this invention. Explanatory drawing which illustrates typically the absorption characteristic with respect to the external light of the optical structure of this invention.

Hereinafter, embodiments in which the optical structure of the present invention is applied to a mobile phone will be described with reference to the drawings.
Example 1
As shown in FIGS. 1 and 2, the mobile phone 10 has an outer shape in which a lid side housing 11 and a main body side housing 12 are connected by a hinge portion 13. In the first embodiment, the mobile phone 10 has a built-in one-segment tuner and can watch terrestrial digital television broadcasting. The lid-side and body-side casings 11 and 12 can be opened and closed by a hinge portion 13, folded in a solid state in FIG. 1 in a portable state, and opened in a virtual line in a usable state as a telephone or the like. Will be exposed.
As shown in FIG. 2, a touch panel 15 is disposed on the inner surface of the main body side housing 12. The user touches the surface of the touch panel 15 and performs an input operation. On the touch panel 15, the optical film 17 of FIG. 3 on which design patterns of numeric keys and various menu keys are displayed is disposed. The input contents executed when the touch panel 15 is touched correspond to the key positions of the optical film 17. For example, the user performs various operations such as inputting a telephone number by touching a predetermined design pattern portion on the surface of the touch panel 15.
As shown in FIG. 3, two types of blue and red LEDs 18 (λtyp: 470 nm) and 19 (λtyp: 630 nm) as a visible light source are alternately and regularly arranged on the back surface side of the touch panel 15. An optical display device is constituted by the optical film 17 and the LEDs 18 and 19. A large monitor 20 is disposed on the inner surface of the lid-side housing 11. The mobile phone 10 includes other normal mechanisms as a mobile phone, such as a photographing lens, a modem, a microphone, a receiver, a transmission / reception unit, an antenna, and the like, but description thereof is omitted.
The touch panel 15 displays the design pattern of the numeric keypad and various menu keys by emitting light for a certain period of time by opening the lid side casing 11. It is possible to display the backlight in either direction of FIGS. 4A and 4B by the user's input switching. In this embodiment, when the vertical design pattern is selected, the blue LED 18 is emitted, the vertical design pattern as shown in FIG. 4A is displayed, and the vertical design pattern is displayed in blue light. When the horizontal design pattern is selected, the red LED 19 emits light, and the horizontal design pattern as shown in FIG. 4B is displayed with red light. The visible light from the blue LED 18 is the first irradiation light, and the visible light from the red LED 19 is the second irradiation light.
On the other hand, in the default state where neither the blue LED 18 nor the red LED 19 is lit, for example, the company name of the manufacturer of the mobile phone 10 as shown in FIG. 4C is displayed in white on a black background. .

Next, the structure of the optical film 17 having the above visibility will be described.
As shown in FIG. 3, the optical film 17 has a two-sheet configuration in which two first and second transparent substrates 21 and 22 are overlapped. The first transparent substrate 21 is disposed on the upper layer (outer side). As shown in FIG. 5, a reflective layer 23 is formed on the upper surface of the first transparent substrate 21. A shielding layer 24 is formed on the lower surface of the first transparent substrate 21. In Example 1, the reflective layer 23 is formed by printing, and the shielding layer 24 is formed by vapor deposition. A mask layer 26a is formed on the upper surface of the second transparent substrate 22, and a second mask layer 26b is formed on the lower surface. The first and second mask layers 26a and 26b are formed by printing.
As shown in FIG. 4A, the first mask layer 26a has a character portion that is negative as a negative design pattern P1, and the second mask layer 26b has a character portion as shown in FIG. 4B. As a negative, the design pattern P2 is horizontally cut out. The reflective layer 23 is a design pattern P3 in which the character portion shown in FIG. The shielding layer 24 shields the entire area of the first transparent substrate 21.
The first mask layer 26a shows the optical characteristics of (2) in the graph of Table 1 showing the transmission-absorption characteristics, the second mask layer 26b shows the optical characteristics of the graph (1) of Table 1, and the shielding layer 24. Indicates the optical characteristics of the graph (3) in Table 1.
The optical characteristics of each layer are written specifically for the visible light region only.

As shown in graph (1) of Table 1, the second mask layer 26b has a transmittance of about 80% on average with a peak at around 470 nm for light in the wavelength group of 450 nm to 500 nm that is a wavelength group centered on blue. For light in the vicinity of 600 nm to 750 nm, which is a wavelength group centered on red, the transmittance is set to about 2% on average (absorbance about 98% on average). That is, the second mask layer 26b has a very high transmittance for blue and absorbs visible light in the vicinity of red. Therefore, when the second mask layer 26b is viewed by itself, the second mask layer 26b exhibits blue.
On the other hand, as shown in the graph (2) of Table 1, the first mask layer 26a has an average transmittance of 5% or less (average 95) for light around 450 nm to 500 nm which is a wavelength group centered on blue. The absorption rate is set to a very high transmittance of about 90% on average for light of 600 nm to 750 nm which is a wavelength group centering on red. That is, since the first mask layer 26a has a very high transmittance for red and absorbs visible light in the vicinity of blue, the first mask layer 26a exhibits a red color when viewed alone.

Further, as shown in the graph (3) of Table 1, the shielding layer 24 has an average transmittance of about 50% with a peak at around 440 nm for light around 400 nm to 500 nm which is a wavelength group centered on blue. The transmittance is about 70% on average for light in the vicinity of 650 nm to 750 nm, which is a wavelength group centered on red. And in the middle 530-600 nm vicinity, it is set to the transmittance | permeability of 20% or less on average (absorption rate of about 80% on average).
That is, since the shielding layer 24 has sufficient transmission performance for both blue and red, when the blue LED 18 or the red LED 19 is turned on, the design pattern P1 of the first mask layer 26a The first irradiation light or the second irradiation light of the design pattern P2 of the second mask layer 26b is transmitted and can be viewed from the upper layer side. Further, when the absorption characteristics of the first and second mask layers 26a and 26b are combined, a purple color is obtained, and when the absorption characteristics of the shielding layer 24, mainly green-type absorption characteristics around 530 to 600 nm, are combined here, the shielding layer 24 is obtained. When viewed in the default state, the reflective layer 23 emerges from a very dark background that is almost black. In Example 1, since the average transmittance of the shielding layer 24 is set to about 25%, the average transmittance of the overlapping portion of the first and second mask layers 26a and 26b is set to be less than this.

The reflective layer 23 must be visible so that it can be seen in the default state, and has a reflectance such that it cannot be seen by the backlight of the first or second irradiation light. In Example 1, the regular reflectance by a lens reflectometer (manufactured by Olympus) is set to 5%, and the transmittance is set to about 90%. Therefore, both the first irradiation light of the blue LED 18 and the second irradiation light of the red LED 19 are transmitted through the reflective layer 23 and viewed.
Table 2 shows the relationship between the reflectance of the reflective layer and the transmittance with the shielding layer 24 in the background when the backlight (visible light source) is turned on. As measurement conditions, (A) When a 630 nm red light source is used as a backlight in the absence of external light, (B) When the same red light source is used as a backlight under 700 lux indoor fluorescent lamp illumination as an external light condition (C) In the case where a white spotlight was used in addition to 700 lux indoor fluorescent lamp illumination as an external light condition, and the same red light source was used as a backlight under illumination of 1800 lux, it was performed under three conditions. The backlight takes into account the light of the first design pattern that passes through the mask layers 26a and 26b. The regular reflectance was measured in the luminous reflection band (green reflectance). Actually, strong external light conditions such as (C) can only be in places under direct sunlight, but they are listed as comparative examples.
The reflection layer 23 of Example 1 corresponds to the sample 4, and the transmittance of the shielding layer 24 of Example 1 is 25% as described above, and it is determined that it can be slightly seen under the condition (B) when the backlight is turned on. However, in practice, since there are many overlapping portions of the illumination pattern that transmits the design patterns P1 and P2 of the first and second mask layers 26a and 26b and the design pattern P3 of the reflective layer 23, the amount of irradiation light increases overall. It becomes difficult to see. That is, the reflective layer 23 of Example 1 can be used.
As long as the samples 3 to 5 are “slightly visible”, the optical structure of the present invention can be used sufficiently depending on the contrast with the irradiation light. However, in the samples 1 and 2 that are judged to be “visible when lit”, the transmittance is very low, and when the luminance of the irradiation light is extremely high relative to the luminance of the outside light, It is visible by contrast. However, when the reflectance exceeds 10%, the reflective layer can be visually observed even if the luminance of the irradiated light is increased, and if the luminance is too high, the design patterns P1 and P2 are difficult to discriminate due to the diffused light.
In addition, the design patterns P1 and P2 are not disturbed by the reflection layer 23 if the luminance of the irradiated light is twice or more that of the external light.

  In the mobile phone 10 having such a configuration, when the blue or red LEDs 18 and 19 are lit as backlights, any pattern is emitted in the selected direction, and the numeric keypad and various menus are displayed on the surface of the touch panel 15. The key will be visible. On the other hand, when neither the blue or red LEDs 18 and 19 are lit, the white “TOKAI” in the reflective layer 23 overlaps the shielding layer 24 and the first and second mask layers 26a and 26b by external light. It will be visually observed against the background color of black.

(Example 2)
Next, Example 2 in which the structure of the optical film 17 is different will be described. Since the second embodiment is different from the first embodiment only in the optical film 17, the description of the mobile phone 10 described above is omitted.
Also in Example 2, the optical film 17 has the same layer structure as that of FIG. 5 and the optical characteristics of the reflective layer 23 and the first and second mask layers 26a and 26b are the same, but only the optical characteristics of the shielding layer 24 are different. ing.
The shielding layer 24 in Example 2 is a kind of reflective film, and its optical characteristics show almost flat optical characteristics in the visible range as shown in the graph of Table 3 showing transmission-reflection characteristics, and an average of 20% transmission. Rate is set. In the second embodiment, when the blue or red LEDs 18 and 19 are lit as backlights, any one of the patterns emits light in the selected direction. Thus, the numeric keypad and various menu keys are visually observed on the surface of the touch panel 15. On the other hand, when neither the blue or red LEDs 18 and 19 are lit, the white “TOKAI” of the weak reflective layer 23 of 4 to 10% is visually observed against the background of the shielding layer 24 shining in a metallic color by external light. The Rukoto.

(Example 3)
Next, Example 3 in which the structure of the optical film 17 is different will be described. Since Example 3 is also different from Example 1 only in the optical film 17, the description of the above-described mobile phone 10 is omitted.
In Example 3, the optical film 17 has the reflective layer 23, the shielding layer 24, and the optical characteristics of the first and second mask layers 26a and 26b, all of which are the same as those in Example 1. However, as shown in FIG. The shielding layer 24 has a layer structure in which the top and bottom are interchanged.
In the mobile phone 10 having such a configuration, when the blue or red LEDs 18 and 19 are lit as backlights, any pattern is emitted in the selected direction, and the numeric keypad and various menus are displayed on the surface of the touch panel 15. The key will be visible. On the other hand, when neither the blue or red LEDs 18 and 19 are lit, the light “TOKAI” in the reflective layer 23 is transmitted through the shielding layer 24 by the external light and the shielding layer 24 and the first and second masks are displayed. The black outer peripheral color where the layers 26a and 26b overlap is visually observed against the background. Since the reflective layer 23 is transmitted through the shielding layer 24, the reflective layer 23 is visually observed slightly darker than the reflective layer 23 according to the first embodiment.
Tables 4 and 5 are tables showing the appearance of the reflective layer 23 under the shielding layer 24, that is, the transmission performance of the shielding layer 24 with respect to the reflective layer 23. Table 4 shows the appearance of only the same 700 lux indoor fluorescent light outside as above, and Table 5 shows the appearance when the same 630 nm red light source is used as the backlight. In Table 4, it is preferable that the reflective layer 23 can be seen by external light. On the contrary, in Table 5, it is preferable that the reflective layer 23 cannot be seen by the backlight.
Example 3 corresponds to Sample 4 as described above, and the regular reflectance of the reflective layer 23 is 5%. On the other hand, the shielding layer 24 is set to an average transmittance of 25%. Sample 4 is slightly visible under the condition of only external light without backlight in Table 4. It is a judgment. Actually, it is possible to make the setting so that it can be seen better by increasing the transmittance or the reflectance. On the other hand, it is determined that the sample 4 is still slightly visible even under the condition of the backlight shown in Table 5. On the contrary, it is better not to see the reflective layer 23 under the condition of the backlight. However, as described in the first embodiment, the design patterns P1, P2 of the first and second mask layers 26a, 26b are actually used. Since there are many overlapping portions of the illumination pattern that transmits light and the design pattern P3 of the reflective layer 23, the reflective layer 23 becomes difficult to see, so there is no problem.

It should be noted that the present invention can be modified and embodied as follows.
In the above description, the shielding layer 24 has a characteristic corresponding to a characteristic obtained by combining the optical characteristics of the first and second mask layers 26a and 26b, but a flat characteristic, for example, visible light as shown in the graph (4) in Table 1 You may make it set to the transmittance | permeability fixed in the area | region (range of 400-750 nm). Although the background of the reflective layer 23 is slightly thinned by using such a flat characteristic, the light of the blue or red LEDs 18 and 19 transmitted through the first and second mask layers 26a and 26b is conversely clearer. Become. In addition, it is easy to adjust the light amount balance between the blue illumination light amount and the red illumination light amount. In addition to the vapor deposition, the shielding layer 24 may use a commercially available dimming film.
-Although the background was black in the said Example 1, by adjusting the absorption characteristic of the shielding layer 24, it is possible to make various colors look visually as a background of the reflection layer 23 in a default state.
In the above embodiment, the first mask layer 26a is set to transmit blue, and the second mask layer 26b is set to transmit red. However, other colors may be combined.
The setting of the optical characteristics of the first and second mask layers 26a and 26b and the shielding layer 24 in the optical film 17 is an example, and other characteristics may be used.
The order of the first and second mask layers 26a and 26b may be reversed.
A protective film may be provided on the reflective layer 23.
-The light source for irradiation is preferably a monochromatic light source such as an LED or a laser, but a light source such as a light bulb combined with a thin film may be used, and it is preferable to use a light guide plate or a diffusion plate as the irradiation light.
In addition, when ultraviolet rays are used for the external light or the irradiation light source and a fluorescent agent or a phosphorescent agent is mixed in the shielding layer and the reflective layer, the ultraviolet rays are converted into visible light in the mixed layer so that the design pattern can be visually observed.
In addition, it is free to implement in a mode that does not depart from the spirit of the present invention.

  DESCRIPTION OF SYMBOLS 10 ... Mobile phone, 17 ... Optical film as an optical structure, 21, 22 ... Transparent substrate, 23 ... Reflective layer, 24 ... Shielding layer, 26a, 26b ... Mask layer, P1, P2, P3 ... Design pattern.

Claims (9)

In an optical structure formed by forming a plurality of thin film layers on a single transparent substrate or a plurality of transparent substrates,
The plurality of thin film layers are:
A mask layer in which the first design pattern made up of characters, symbols or figures is hollowed out so as to have either a negative or positive relationship;
A predetermined absorptivity for obtaining a density at which the first design pattern of the mask layer cannot be seen through by external light, or a reflectance that reflects the external light to a degree that cannot be seen through, is provided on the mask layer. And a shielding layer having a predetermined transmittance that transmits the irradiation light irradiated from behind the mask layer through the hollow portion;
A second design pattern comprising a character, a symbol, a figure, or the like, disposed on the shielding layer, having a predetermined reflectance for reflecting the external light and having a predetermined transmittance for transmitting the irradiation light; A reflective layer hollowed out to be in either a negative or positive relationship,
The optical structure is characterized in that the transmittance in the reflective layer is set larger than the reflectance. In an optical structure formed by forming a plurality of thin film layers on a single transparent substrate or a plurality of transparent substrates,
The plurality of thin film layers are:
A mask layer in which the first design pattern made up of characters, symbols or figures is hollowed out so as to have either a negative or positive relationship;
A second design pattern made of characters, symbols, figures or the like, which is disposed on the mask layer and has a predetermined reflectance for reflecting external light and having a predetermined transmittance for transmitting the irradiation light, is negative. Or a reflective layer hollowed out so as to be in any positive relationship,
A predetermined absorptivity for obtaining a density at which the first design pattern of the mask layer cannot be seen through by the external light, or a reflectance that reflects the external light to a degree that cannot be seen through. And a shielding layer having a predetermined transmittance that transmits the reflected light of the reflective layer by the external light and the irradiation light irradiated from behind the mask layer through the hollow portion of the mask layer;
The optical structure is characterized in that the transmittance in the reflective layer is set larger than the reflectance. The mask layer is composed of a plurality of mask layers stacked adjacent to each other, and each of the mask layers does not specifically transmit irradiation light in a predetermined wavelength range, and each of the other mask layers specifically The optical structure according to claim 1 or 2, wherein irradiation light in a predetermined wavelength range that is not transmitted is transmitted. The mask layer has an absorption characteristic that does not specifically transmit irradiation light in a predetermined wavelength range, and the shielding layer has an absorption characteristic corresponding to an absorption characteristic obtained by combining the optical characteristics of the plurality of mask layers. The optical structure according to claim 3. The optical structure according to claim 3 or 4, wherein the plurality of mask layers are two first and second mask layers. The first mask layer does not specifically transmit the irradiation light in the red wavelength region and transmits visible light in the other wavelength region, and the second mask layer specifically transmits the irradiation light in the blue wavelength region. The optical structure according to claim 5, wherein the optical structure is not allowed to pass through and visible light in other wavelength regions is allowed to pass through. The optical structure according to any one of claims 1 to 6, wherein the reflectance of the reflective layer with respect to external light is 4% or more and less than 10%. A visible light source that emits visible light of a predetermined wavelength;
A mask layer in which the first design pattern composed of characters, symbols, figures, etc. arranged in front of the visible light source is hollowed out so as to have either a negative or positive relationship;
The mask layer is disposed above the mask layer, and has a predetermined absorptivity for obtaining a density at which the first design pattern of the mask layer cannot be seen through by external light, or a reflectance that reflects external light to a degree that cannot be seen through. A shielding layer having a predetermined transmittance that transmits the irradiation light irradiated from the visible light source behind the mask layer through the hollow portion;
A second design pattern comprising a character, a symbol, a figure, or the like, disposed on the shielding layer, having a predetermined reflectance for reflecting the external light and having a predetermined transmittance for transmitting the irradiation light; An optical display device comprising a reflective layer in which the transmittance is set to be larger than the reflectance so as to have either a negative or positive relationship. A visible light source that emits visible light of a predetermined wavelength;
A mask layer in which the first design pattern composed of characters, symbols, figures, etc. arranged in front of the visible light source is hollowed out so as to have either a negative or positive relationship;
A second design pattern made of characters, symbols, figures or the like, which is disposed on the mask layer and has a predetermined reflectance for reflecting external light and having a predetermined transmittance for transmitting the irradiation light, is negative. Alternatively, a reflective layer in which the transmittance that has been hollowed out so as to be in any positive relationship is set larger than the reflectance,
A predetermined absorptivity for obtaining a density at which the first design pattern of the mask layer cannot be seen through by the external light, or a reflectance that reflects the external light to a degree that cannot be seen through. And a shielding layer having a predetermined transmittance that transmits the reflected light of the reflective layer by the external light and the irradiation light irradiated from behind the mask layer through the hollow portion of the mask layer. Display device.

Images