Digital signage system

A digital signage system includes a transducer configured to transform a pressure to an electrical signal; a control apparatus configured to change information in association with the intensity of the electrical signal; and an output apparatus configured to output the information to an output target based on a command of the control apparatus.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a digital signage system.

2. Description of the Related Art

In recent years, a digital signage system is in widespread use as one means for an advertisement. This system advertises an advertisement image in a digital signage provided in a shop, a station, or a public space. Thus, the system advertises to a great number of users. The advertisement image may be either a moving image or a still image. The advertisement image has a greater information amount than that of a paper medium, and is frequently displayed by appropriately switching over at a constant time period. Therefore, viewing time is required to be extended in order to enhance customer appeal.

In relation thereto, for example, there is proposed a technique of enhancing an advertising effect by disabling a part of information displayed on a digital signage when a user notices an existence of the digital signage (for example, Patent Document 1).

Further, if a person moves in front of a screen, there is proposed a technique of effectively providing information and enhancing the visibility by dynamically changing an output position of a window and a content to be output on the screen in conformity with a natural motion of the person. For example, a window moves in conformity with the motion of the person in front of the screen.

According to this technique, a position detection means determines a coordinate on a screen on which information is output after providing a coordinate conversion to the position of the person and a finger pointing direction, which are detected from an image captured by a camera (for example, Patent Document 2).

There is also proposed a technique of three-dimensionally detecting the position using combined multiple cameras and reflecting to the image (for example, Patent Document 3).

SUMMARY OF THE INVENTION

However, according to the above techniques, the cameras are used. It is not possible to sufficiently improve the visibility of a pedestrian by such systems using the cameras.

The first reason is a complicated and heavy process, in which a color or a contour is extracted from an image and differences are obtained from the immediately former frame and the immediately latter frame.

The second reason is an insufficient data acquisition caused by a late data acquisition in a case where a process time is limited and a quick motion such as a running person is captured. In this case, if the frame rate is increased, the data acquisition becomes sufficient. However, because the increase of the frame rate causes an excessive increase of the process data and a further heavy system, the increase of the frame rate is not preferable.

The third reason is a necessity of a minute adjustment and a limited location, with which an optical environment variation such as a strong light or rain is prevented from occurring, to avoid influences of an ambient brightness and a color change.

The fourth reason is a dead angle occurring in cases where multiple persons pass or where a passage having a complicated shape, a pole, or the like exist.

Accordingly, it is a general object of the present invention to provide a novel and useful digital signage system with an improved visibility.

One aspect of the embodiments of the present invention may be to provide a digital signage system including a transducer configured to transform a pressure to an electrical signal; a control apparatus configured to change information in association with the intensity of the electrical signal; and an output apparatus configured to output the information to an output target based on a command of the control apparatus.

Additional objects and advantages of the embodiments will be set forth in part in the description which follows, and in part will be clear from the description, or may be learned by practice of the invention. Objects and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A description is given below, with reference to theFIG. 1throughFIG. 12Cof embodiments of the present invention. Where the same reference symbols are attached to the same parts, repeated description of the parts may be omitted.

FIG. 1illustrates a digital signage system of an embodiment. In the digital signage system1, pedestrian information sent from a detection sensor10is input into a control apparatus20, and an image of an advertisement or the like is projected onto a projection face by a projection apparatus30upon a command from the control apparatus20. Further, information can be changed in association with a signal intensity of the detection sensor10.

A transducer converting a pressure to an electrical signal is used as the detection sensor10. A specific example of the transducer is an electric generating element using a front and back hardness difference of an elastic body or the like. Further, a piezoelectric material, in which polarization is eccentrically located and fixed, a friction electric generating element using peeling electrification due to a difference in triboelectric series, and an electret electric generating element using an electret material previously provided with an energy deposition process may be used.

The control apparatus20may be structured to include a central processing unit (CPU), a read only memory (ROM), and a main memory, for example. In this case, various functions of the control apparatus20are substantialized such that a program stored in the ROM or the like is read out to the main memory and executed by the CPU. However, a part or all of the control apparatuses20may be substantialized only by hardware. The control apparatus20may be physically formed by multiple apparatuses. The control apparatus20is, for example, a personal computer.

In the control apparatus20, software performing an algorithm for processing data is operated to process how to display a previously prepared advertisement data and a previously prepared program (a display position, a switchover timing, or the like) and to send a command to the projection apparatus30.

The projection apparatus30is, for example, a projector, a liquid crystal display TV, a plasma display TV, an image display apparatus which can change a color for each element, or the like. The projection apparatus30may project information such as an advertisement on a projection face (a screen). However, as described later, a place where the information is projected may be an object other than the projection face (the screen).

The algorithm for processing the data can convert a voltage waveform at a contact position input from, for example, the detection sensor10to position information. Further, the algorithm for processing the data can predict the state of a body, a characteristic of walking, the sex, the age, and so on and can perform a selection of display data to the projection apparatus30, a change of the switchover timing, a height adjustment of the display position, or the like, by analyzing, patterning, and combining the additional information.

The additional information is, for example, the acceleration, the weight, the weight shift, the size of foot of the pedestrian, and so on, which correspond to a gradient of a rise in the voltage waveform at the contact position input from the detection sensor10. Alternatively, as illustrated inFIG. 2, the additional information may be features of electrical signals of output waveforms in cases where the load directions are pressurizing and depressurizing directions relative to the detection sensor.

The information to be changed is the image in this embodiment and the embodiment described below. However, the information to be changed is not limited to the image and may be a voice, an ultrasonic sound wave, or an electromagnetic wave. The previously prepared advertisement data may be previously recorded inside the control apparatus20, may be appropriately input as the data and the program recorded in the recording medium, or may be downloaded as a program or data similar thereto from a network. At this time, the control apparatus20may be connected to the network by either a wired or wireless connection.

Next, referring toFIG. 3, the digital signage system1is described further in detail.FIGS. 3A, 3B, and 3Cillustrate an exemplary digital signage system of the embodiment.FIG. 3Ais a front view,FIG. 3Bis a plan view, andFIG. 3Cis side view.

Referring toFIGS. 3A-3C, a projection face (a screen)102is installed in a wall101at a position where a pedestrian200can view. The control apparatus20is installed above the pedestrian200and on the wall101. Further, the multiple projection apparatuses30are supported by brace members103at a predetermined interval. A plurality of transducers are arranged on a floor104at a predetermined interval as the detection sensor10.

When the pedestrian200walks on the floor104, the detection sensor10installed in the floor104detects a motion of the pedestrian200, pedestrian information received from the detection sensor10is input in the control apparatus20, and the projection apparatus30projects an image300onto the projection face102upon a receipt of the command from the control apparatus20. The image300can be displayed in association with the motion of the pedestrian200so that the image300is displayed at a diagonally forward position of the pedestrian2for a long time. The image300is, for example, an advertisement.

The operation image of the digital signage system1is illustrated inFIGS. 4A-6C.FIGS. 4A-4Cillustrate exemplary operation image in a case where the pedestrian walks alone. In the case where the pedestrian walks alone as illustrated inFIGS. 4A-4C, the detection sensor10installed in the floor104, on which the pedestrian200walks, detects the motion of the pedestrian200, and the pedestrian information is input from the detection sensor10to the control apparatus20.

As illustrated inFIG. 4A, the control apparatus20commands the projection apparatus30on the left side based on the pedestrian information received from the detection sensor10. Then, the projection apparatus30on the left side displays “A” as the image300at, for example, a diagonally forward position of the pedestrian200. In association with the walk of the pedestrian200, “A” moves in the same direction as the movement of the pedestrian200and is continuously displayed for a predetermined time.

As illustrated inFIG. 4B, when the pedestrian200further moves in the direction of an arrow, the control apparatus20commands the projection apparatus30at the center based on the pedestrian information received from the detection sensor10. Then, the projection apparatus30at the center displays “B” as the image300at, for example, the diagonally forward position of the pedestrian200. In association with the walk of the pedestrian200, “B” moves in the same direction as the movement of the pedestrian200and is continuously displayed for a predetermined time.

As illustrated inFIG. 4C, when the pedestrian200further moves in the direction of the arrow, the control apparatus20commands the projection apparatus30on the right side based on the pedestrian information received from the detection sensor10. Then, the projection apparatus30on the right side displays “C” as the image300at, for example, the diagonally forward position of the pedestrian200. In association with the walk of the pedestrian200, “C” moves in the same direction as the movement of the pedestrian200and is continuously displayed for a predetermined time.

FIG. 5illustrates an operation image in a case where multiple pedestrians (here, pedestrians200and210) continuously pass through in the same direction. In the case where the multiple pedestrians continuously move as illustrated inFIG. 5, the detection sensor10installed in the floor104, on which the pedestrian200walks, detects the motion of the pedestrian200, and the pedestrian information is input from the detection sensor10to the control apparatus20. Simultaneously, the detection sensor10installed in the floor104, on which the pedestrian210walks, detects the motion of the pedestrian210, and the pedestrian information received from the detection sensor10is input into the control apparatus20.

The control apparatus20commands the projection apparatus30based on the pedestrian information received from the detection sensor10installed in the floor104, on which the pedestrian200walks. Then, the projection apparatus30on the left side displays “A” as the image300at, for example, a diagonally forward position of the pedestrian200. In association with the walk of the pedestrian200, “A” moves in the same direction as the movement of the pedestrian200and is continuously displayed for a predetermined time.

Simultaneously, the control apparatus20commands the projection apparatus30based on the pedestrian information received from the detection sensor10installed in the floor104, on which the pedestrian210walks. Then, the projection apparatus30on the right side displays “C” as the image300at, for example, the diagonally forward position of the pedestrian210. In association with the walk of the pedestrian200, “C” moves in the same direction as the movement of the pedestrian200and is continuously displayed for a predetermined time.

FIGS. 6A-6Cillustrates an operation image in a case where multiple pedestrians (here, pedestrians200and210) continuously pass through in the same direction. In the case where the multiple pedestrians continuously move as illustrated inFIGS. 6A-6C, the detection sensor10installed in the floor104, on which the pedestrian200walks, detects the motion of the pedestrian200, and the pedestrian information is input from the detection sensor10to the control apparatus20. Simultaneously, the detection sensor10installed in the floor104, on which the pedestrian210walks, detects the motion of the pedestrian210, and the pedestrian information received from the detection sensor10is input into the control apparatus20.

The control apparatus20commands the projection apparatus30based on the pedestrian information received from the detection sensor10installed in the floor104, on which the pedestrian200walks. Then, the projection apparatus30on the left side displays “A” as the image300at, for example, a diagonally forward position of the pedestrian200. In association with the walk of the pedestrian200, “A” moves in the same direction as the movement of the pedestrian200and is continuously displayed for a predetermined time.

Simultaneously, the control apparatus20commands the projection apparatus30based on the pedestrian information received from the detection sensor10installed in the floor104, on which the pedestrian210walks. Then, the projection apparatus30on the right side displays “C” as the image300at, for example, the diagonally forward position of the pedestrian210. In association with the walk of the pedestrian210, “C” moves in the same direction as the movement of the pedestrian210and is continuously displayed for a predetermined time.

As illustrated inFIG. 6B, when the pedestrians200and210further move respectively in the directions of arrows, the control apparatus20commands the projection apparatus30at the center based on the pedestrian information received from the detection sensor10installed in the floor, on which the pedestrian200walks. Then, the projection apparatus30on the center displays “B” as the image300at, for example, the diagonally forward position of the pedestrian200. In association with the walk of the pedestrian200, “B” moves in the same direction as the movement of the pedestrian200and is continuously displayed for a predetermined time.

Simultaneously, the control apparatus20commands the projection apparatus30based on the pedestrian information received from the detection sensor10installed in the floor104, on which the pedestrian210walks. Then, the projection apparatus30on the center displays “B” as the image300at, for example, the diagonally forward position of the pedestrian210. In association with the walk of the pedestrian210, “B” moves in the same direction as the movement of the pedestrian210and is continuously displayed for a predetermined time.

As illustrated inFIG. 6C, when the pedestrians200and210further move respectively in the directions of arrows after the pedestrians200and210pass each other, the control apparatus20commands the projection apparatus30on the right side based on the pedestrian information received from the detection sensor10. Then, the projection apparatus30on the right side displays “C” as the image300at, for example, the diagonally forward position of the pedestrian200. In association with the walk of the pedestrian200, “C” moves in the same direction as the movement of the pedestrian200and is continuously displayed for a predetermined time.

Simultaneously, the control apparatus20commands the projection apparatus30based on the pedestrian information received from the detection sensor10installed in the floor104, on which the pedestrian210walks. Then, the projection apparatus30on the left side displays “A” as the image300at, for example, a diagonally forward position of the pedestrian210. In association with the walk of the pedestrian210, “A” moves in the same direction as the movement of the pedestrian210and is continuously displayed for a predetermined time.

Although the number of the projection apparatuses30is three inFIGS. 4A-6C, the number of the projection apparatuses30is not limited. For example, a bigger screen may be structured by further increasing the number. A wider range may be projected by fewer projection apparatuses30.

Referring toFIGS. 4A-6C, the installation locations of the projection apparatuses30are portions of the wall101above the pedestrian200. However, the installation locations of the projection apparatuses30may be portions of the wall101below or beside (in the vicinity of the center in the up and down directions).

Referring toFIGS. 4A-6C, the place where the image300is projected is the projection face102(the screen). However, the image300may be projected onto something other than the projection face (the screen). For example, the image300may be projected onto the detection sensor10.

FIGS. 7A-7Cillustrate an exemplary case where the image is projected onto the detection sensor.FIG. 7Ais a front view,FIG. 7Bis a plan view, andFIG. 7Cis a side view.

Referring toFIGS. 7A-7C, a predetermined character is displayed as the image300for a child220. For example, the child220can joyfully play if it is provided that the image300(a character) moves when the child220uses a tool so that the tool400touches the image300displayed on the predetermined process. As described, a further interactive system is substantialized when the image300is projected onto the detection sensor10.

FIGS. 7A-7Care different fromFIGS. 3A-Cat points where multiple transducers are arranged as the detection sensors10not only on the floor104but also on the wall101. Although the detection sensors10are installed in the three faces of the wall101inFIGS. 7A-7C, it is possible to appropriately determine the face of the wall101, in which the detection sensors10are to be installed. Alternatively, the detection sensors10may be installed in any one of the wall101and the floor104.

Referring toFIGS. 3A-3C, the shape of the detection sensors10is long and thin. Referring toFIGS. 7A-7C, the shape of the detection sensors10is substantially square, and more detection sensors10are installed per the same area. With this, a display of the screen300can be switched over in association with a smaller motion of the child220.

Here, various structural portions of the digital signage system1are described in more detail.

FIGS. 8A-8Cillustrate the structure of the transducer used as the detection sensor10.FIGS. 8A-8Cillustrate an exemplary structure of the transducer. The structure of the transducer is not limited toFIGS. 8A-8C.

Referring toFIG. 8A, a basic form in which an intermediate layer11is interposed between the first electrode12and the second electrode13, is illustrated. Referring toFIG. 8B, a space is provided between the intermediate layer11and the second electrode13using a coil spring14and a support pedestal15. This structure contributes an improvement on an electric-generating capacity. Referring toFIG. 8C, a leaf spring and a support pedestal17are used instead of the coil spring14and the support pedestal15. The structure illustrated inFIG. 8Ccan improve the durability more than the structure illustrated inFIG. 8B.

Described in detail below is the intermediate layer11, the first electrode12, and the second electrode13of the transducer.

The materials, the shapes, the sizes, and the structures of the first electrode12and the second electrode13are not specifically limited and can be appropriately selected depending on a purpose. The materials, the shapes, the sizes, and the structures of the first electrode12and the second electrode13may be the same or different. However, the materials, the shapes, the sizes, and the structures of the first electrode12and the second electrode13are preferably the same.

The material of the first electrode12and the second electrode13is, for example, a metal, a carbon-based conductive material, a conductive rubber composition, or the like.

The conductive rubber composition includes, for example, a conductive filler and a composition containing rubber.

The conductive filler contained in the conductive rubber composition is, for example, a carbon material (for example, ketjenblack, acetylene black, black lead, carbon fiber (CF), carbon nanofiber (CNF), carbon nanotube (CNT), and so on), a metallic filler (gold, silver, platinum, copper, aluminum, and so on), a conductive high-polymer material (a derivative of polythiophene, polyacetylene, polyaniline, polypyrrole, poly-p-phenylene, and poly-p-phenylenevinylene or the derivative added with a dopant such as an anion and a cation), an ionic liquid, or the like.

The shapes of the first electrode12and the second electrode13are, for example, a thin film. The structures of the first electrode12and the second electrode13are, for example, a non-woven fabric in which fiber-like carbon materials pile.

The intermediate layer11may be any as long as a voltage is generated when a load of a pressure is applied. It is preferable that the intermediate layer11has flexibility. The intermediate layer11having flexibility preferably satisfies at least one of the following conditions (1) and (2).

Condition (1): when the intermediate layer11is pressurized in a direction perpendicular to the surface of intermediate layer11, the deformation amount of the intermediate layer11on the side of the first electrode12is different from the deformation amount of the intermediate layer11on the side of the second electrode13.

Condition 2: the universal hardness (H1) at a time of pressurizing the intermediate layer11to retract by 10 μm on the side of the first electrode12is different from the universal hardness (H2) at a time of pressurizing the intermediate layer11to retract by 10 μm on the side of the second electrode13.

As described, a great electric-generating capacity is obtainable by the different deformation amounts or the different hardness on both surfaces of the intermediate layer11. The deformation amount is the maximum pressurized retraction depth of an indenter when the intermediate layer11is pressurized in the following conditions.

Measuring instrument: Instrument for measuring microhardness WIN-HUD manufactured by Fischer Instruments K.K.

Indenter: Quadrangular pyramid diamond indenter having a facing angle of 136°

Load increment time from initial load to maximum load: 10 seconds

The universal hardness can be obtained by the following method.

Measuring instrument: Instrument for measuring microhardness WIN-HUD manufactured by Fischer Instruments K.K.

Indenter: Quadrangular pyramid diamond indenter having a facing angle of 136°

Load increment time from initial load to maximum load: 50 seconds

The ratio (H1/H2) between the universal hardness (H1) and the universal hardness (H2) is preferably equal to or greater than 1.01, more preferably equal to or greater than 1.07, and especially preferably equal to or greater than 1.13. The upper limit value of the ratio (H1/H2) is not specifically limited. The upper limit value of the ratio (H1/H2) is appropriately selected by a degree of a flexibility required by a usage state, a load in the usage state, or the like, and is preferably equal to or greater than 1.70. Here, H1 is the universal hardness of a relatively harder surface, and H2 is the universal hardness of a relatively softer surface.

The material of the intermediate layer11is not specifically limited and can be appropriately selected depending on an objective. For example, silicone rubber, fluoro silicone rubber, acrylic rubber, chloroprene rubber, natural rubber (latex), urethane rubber, fluorine-contained rubber, ethylene-propylene rubber, or the like is mentioned. Among these, silicone rubber is preferable.

The intermediate layer11may contain a filler to give various functionalities. The filler includes, for example, titanium oxide, barium titanate, lead zirconium titanate, zinc oxide, silica, calcium carbonate, carbon black, carbon nanotube, carbon fiber, iron oxide, PTFE, mica, clay mineral, synthetic hydrotalcite, and a metal. In a case where a filler having piezoelectricity or a polarized high molecule (a base material or a filler) is used, it is preferable to provide a polarization treatment.

The average thickness of the intermediate layer11is not specifically limited and can be appropriately selected depending on a purpose. From a point of view of a deformation following capability, the average thickness of the intermediate layer11is preferably 1 μm to 10 mm, more preferably 50 μm to 200 μm. If the average thickness is within a preferable range, the film formation capability is ensured and the deformation is not prevented so as to enable good electric generation.

The intermediate layer11is preferably insulative. The insulative property is preferably a volume resistivity equal to or greater than 108Ωcm, more preferably a volume resistivity equal to or greater than 1010Ωcm. The intermediate layer11may be a multi-layer structure.

As a method of differentiating the deformation amounts or the hardness of the both surfaces of the intermediate layer11, there are, for example, a surface modification process, an inactivation process, and so on. Both or one of the surface modification process and the inactivation process may be performed.

The surface modification process is, for example, a plasma process, a corona discharge process, an electron beam irradiation process, an ultraviolet ray irradiation process, an ozonation process, a radiant ray irradiation process of irradiating an X-ray, an alpha-ray, a beta-ray, a gamma-ray, or a neutron ray, or the like. From a point of a processing speed, the plasma process, the corona discharge process, and the electron beam irradiation process are preferable among these processes. The processes are not limited to these as long as the material can be reformed.

In a case where the plasma process is performed, a plasma generation apparatus is, for example, a parallel plate type, a capacitive coupling type, or an inductive coupling. Meanwhile, the plasma generation apparatus may be an atmospheric plasma apparatus. From a point of view of durability, a low-pressure plasma spraying is preferable.

The reaction pressure in the plasma process is not specifically limited and can be arbitrarily selected depending on the objective. The reaction pressure is preferably 0.05 Pa to 100 Pa, more preferably 1 Pa to 20 Pa.

A reaction atmosphere in the plasma process is not specifically limited and can be appropriately selected depending on the objective. The reaction atmosphere is effective when an inactive gas, a rare gas, an oxygen gas, or another gas are used, for example. An argon gas is preferable in view of continuousness of an effect. At this time, an oxygen partial pressure is preferably equal to or smaller than 5,000 ppm. When the oxygen partial pressure in the reaction atmosphere is equal to or smaller than 5,000 ppm, ozone can be prevented from being produced. Therefore, a use of an ozone process apparatus can be prevented.

The irradiation electric energy in the plasma process is determined by (output×irradiation time). The irradiation electric energy is preferably 5 Wh to 200 Wh, more preferably 10 Wh to 50 Wh. When the irradiation electric energy is within a preferable range, it is possible to provide an electric generation function to the intermediate layer11and prevent the durability from being degraded by excessive irradiation.

An applied energy (an integration energy) in a corona discharge process is preferably 6 J/cm2to 300 J/cm2, more preferably 12 J/cm2to 60 J/cm2. When the applied energy is within a preferable range, it is possible to provide an electric generation function to the intermediate layer11and prevent the durability from being degraded by excessive irradiation.

The irradiation amount in the electron beam irradiation is preferably equal to or greater than 1 kGy, more preferably 300 kGy to 10 MGy. When the irradiation amount is within a preferable range, it is possible to provide an electric generation function to the intermediate layer11and prevent the durability from being degraded by excessive irradiation.

An irradiation atmosphere in the electron beam irradiation process is not specifically limited and can be appropriately selected depending on the objective. The irradiation atmosphere is preferably formed by filling with an inactive gas of argon, neon, helium, nitrogen, or the like and making the oxygen partial pressure equal to or smaller than 5,000 ppm. When the oxygen partial pressure in the irradiation atmosphere is equal to or smaller than 5,000 ppm, ozone can be prevented from being produced. Therefore, a use of the ozone process apparatus can be prevented.

The wavelength of the ultraviolet rays used in the ultraviolet ray irradiation process is preferably equal to or greater than 200 nm and equal to or smaller than 365 nm, more preferably equal to or greater than 240 nm and equal to or smaller than 325 nm.

The accumulation light amount in the ultraviolet ray irradiation process is preferably 5 J/cm2to 500 J/cm2, more preferably 50 J/cm2to 400 J/cm2. When the accumulation light amount is within a preferable range, it is possible to provide an electric generation function to the intermediate layer11and prevent the durability from being degraded by excessive irradiation.

An irradiation atmosphere in the ultraviolet ray irradiation process is not specifically limited and can be appropriately selected depending on the objective. The irradiation atmosphere is preferably formed by filling with an inactive gas of argon, neon, helium, nitrogen, or the like and making the oxygen partial pressure equal to or smaller than 5,000 ppm. When the oxygen partial pressure in the irradiation atmosphere is equal to or smaller than 5,000 ppm, ozone can be prevented from being produced. Therefore, a use of the ozone process apparatus can be prevented.

It is proposed by the conventional technique that an active group is formed by exciting or oxidizing using a plasma process, a corona discharge process, an electron beam irradiation process, or the like so as to increase an interlayer adhesion force. However, this technique is limitedly applied to the interlayer and is not preferable to apply to the uppermost layer because mold release characteristics are degraded. Further, the reaction is performed in a condition where oxygen is rich so as to effectively introduce a reaction active group (hydroxyl). As described above, the conventional technique is essentially different from the surface modification process of the embodiment.

Because the surface modification process of the embodiment is performed in an reaction environment where there is few oxygen and the pressure is reduced (for example, a plasma process), re-crosslink and bond of the surface are promoted. Therefore, durability is improved due to “increase of Si—O bond having a high binding energy”. Furthermore, mold release characteristics are supposed to be improved due to “densification caused by an improved crosslink concentration” (Although an active group is partly formed in the embodiment, the active group is inactivated by a coupling agent or an air-dry process, which is described later).

The surface of the intermediate layer11may be appropriately provided with an inactivation process using various materials. The inactivation process is not specifically limited as long as the surface of the intermediate layer11is inactivated and can be appropriately selected depending on the objective. For example, the inactivation process may be a process of applying an inactivation agent onto the surface of the intermediate layer11.

The inactivation causes an active group (e.g., —OH) produced by excitation or oxidation due to a predetermined process to react with an inactive agent to reduce an activation level of the surface of the intermediate layer11so that the characteristics of the surface of the intermediate layer11are changed not to be apt to occur a chemical reaction. Here, the predetermined process is, for example, a plasma process, a corona discharge process, a UV irradiation process, or an electron beam irradiation process.

The inactive agent is, for example, an amorphous resin, a coupling agent, or the like. The amorphous resin is, for example, a resin having perfluoropolyetherether as the main chain. The coupling agent is, for example, metal alkoxide or a liquid solution containing metal alkoxide. The metal alkoxide is a chemical compound indicated by the following general expression (1), a partially-hydrolyzed polycondensation product thereof having a degree of polymerization of about 2 to 10, and a mixture of these.
R1(4-n)Si(OR2)nGeneral expression (1)

Here, in the general expression (1), R1and R2respectively and independently represent any one of an alkyl group shaped like a straight chain or a branched-chain having a carbon number of 1 to 10, an alkyl polyetherether chain thereof, and an aryl group thereof. Further, n represents an integer between 2 to 4.

The chemical compound represented by the general expression (1) is specifically dimethyldimethoxysilane, diethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, or tetrapropoxysilane, for example. Especially preferable for the durability is tetraethoxysilane.

In the general expression (1), R1may be a fluoroalkyl group, fluoroalkylacrylate, or etherperfluoropolyether. R1 is preferably perfluoropolyether in view of flexibility and durability.

Further, the metal alkoxide may be formed by one or a mixture of Ti, Sn, Al, and Zr, as a metallic atom, other than Si.

The inactivation process can be performed by coating a surface of an intermediate precursor such as rubber with an inactive agent or causing the surface of the intermediate precursor to be impregnated into the inactive agent by dipping after a surface modification process for the intermediate precursor. In a case where silicone rubber is used as the intermediate precursor, the intermediate precursor may be statically placed in the air so as to be air-dried to deactivate.

A profile of an oxygen concentration in a thickness direction of the intermediate layer11preferably shows a local maximum value.

A profile of a carbon concentration in the thickness direction of the intermediate layer11preferably shows a local minimum value.

It is more preferable that a position corresponding to the local maximum value of the oxygen concentration matches a position corresponding to the local minimum value of the carbon concentration.

The profile of the oxygen concentration and the profile of the carbon concentration may be acquired by an X-ray photoelectron spectroscopy (XPS). The measurement method is, for example, as follows.

Measurement light source: Al (mono)

Relative sensitivity coefficient: using a relative sensitivity coefficient of PHI

In the XPS, an existing concentration ratio and a binding state of an atom in a measurement target can be known by catching an electron flying out by a photoelectron effect.

The silicone rubber has a siloxane bond. The major ingredient of the silicone rubber is Si, O, and C. Therefore, in a case where silicone rubber is used as the material of the intermediate layer11, a wide scan spectrum of XPS is measured to enable the existing concentration ratio (atomic %) in the depth direction of each atom (Si, O, and C) existing inside the surface layer to acquire using a relative peak intensity ratio of each element.FIG. 9Aillustrates this example.FIG. 9Aillustrates a sample of the intermediate layer11acquired by using silicone rubber and providing the surface modification process (the plasma process) and an inactivation process. RegardingFIG. 9A, the abscissa designates an analysis depth in the internal direction from the surface, and the ordinate designates the existing concentration ratio.

Further, in the case of the silicone rubber, it is possible to know an element bound to silicon and a binding state thereof can be known by measuring the energy by which an electron of Si in the 2p orbit flies out. A peak separation is performed for a narrow scan spectrum, which indicates a binding state of Si in the Si2p orbit, so as to acquire the binding state.FIG. 9Billustrates the result of the acquired binding state. The measurement target illustrated inFIG. 9Bis a sample used for the measurement illustrated inFIG. 9A. Referring toFIG. 9B, the abscissa designates the binding energy and the ordinate designates the intensity ratio. From the bottom to the top, the measurement spectrums are illustrated in the depth direction.

Ordinarily, it is known that the amount of the peak shift depends on the binding state. In a case of silicon rubber related to the embodiment, a shift of the peak on the side of a high energy in the Si2p orbit indicates that the number of oxygens bound to Si increases.

With this, when the surface modification process and the inactivation process are provided to the silicone rubber, oxygens increase from the surface layer to the inside so as to have the local maximum value and carbons decrease so as to have the local minimum value. It is known as a result of the analysis in the depth direction that oxygens decrease and carbons increase so as to show an atom existence concentration substantially similar to that of unprocessed silicone rubber.

Further, the local maximum value detected at α in reference ofFIG. 9Amatches the shift (α ofFIG. 9B) of the Si2p binding energy at a higher energy side. This shows that the increase of oxygen is caused by the number of oxygens bound to Si.

FIGS. 10A and 10Billustrate results in unprocessed silicone rubber of analysis similar to the above.

Referring toFIG. 10A, a local maximum value of the oxygen concentration and a local minimum value of the carbon concentration do not exist unlikeFIG. 9A. Further, referring toFIG. 10B, no shift in the Si2p binding energy onto the higher energy side is observed. Therefore, it is confirmed that the number of oxygens bound to Si does not change.

As described, by coating the surface of the intermediate layer11with an inactive agent such as a coupling agent or dipping the intermediate layer11into the inactive agent to permeate, the inactive agent is impregnated into the intermediate layer11. In a case where the coupling agent is a chemical compound expressed by the general expression (1), polyorganosiloxane exists with a concentration distribution in the intermediate layer11. This distribution shows a local maximum value in the depth direction of oxygen atoms contained in polyorganosiloxane. As a result, the intermediate layer11contains polyorganosiloxane having a silicon atom bound to three or four oxygen atoms.

The inactivation process is not limited to a dipping method. For example, it is sufficient that the distribution of the oxygen atoms contained in polyorganosiloxane has a local maximum value in the depth direction (the thickness direction). The inactivation process may be a plasma CVD, PVD, sputtering, combustion chemical vapor deposition, or the like.

The intermediate layer11needs not to have an initial surface potential in a statically placed state. The initial surface potential in the statically placed state can be measured under the following measurement condition. Here, an issue that there is no initial surface potential indicates a voltage within ±10 V at a time of measuring under the following measurement condition.

Preprocessing: after statically placing for 24 hours in an atmosphere of a temperature of 30° C. and a humidity of 40 wet %, electricity is removed for 60 seconds (using SJ-F300 manufactured by Keyence corporation)

At this point, the transducer of the embodiment has a principal of electric power generation different from technique described in Japanese Laid-Open Patent Publication No. 2009-253050, Japanese Laid-Open Patent Publication No. 2014-027756, Japanese Laid-Open Patent Publication No. S54-14696, and so on.

In the transducer of the embodiment, a bias is generated in an electrostatic capacity. This bias is generated due to a difference of a deformation amount based on a hardness difference between both surfaces of the deformation amount by static electrification caused by a mechanism resembling to frictional electrification. This bias is further generated due to generation of a surface potential difference due to an internal electric charge reservation. Therefore, electric charges are assumed to move to generate electric power. However, the principal of this electric power generation is not accurately known.

Within the embodiment, the transducer preferably includes at least a space between the intermediate layer11and the first electrode12or between the intermediate layer11and the second electrode13. As such, it is possible to increase an electric-generating capacity. A method of providing space is not specifically limited and can be appropriately selected in response to an objective. Beside the above structures illustrated inFIGS. 8A-8C, a spacer may be disposed at least between the intermediate layer11and the first electrode12or between the intermediate layer11and the second electrode13.

Hereinafter, a digital signage system1of the embodiment is described based on an example. However, the digital signage system1is not limited to the following example. For example, the example described later is a case where a floor surface is sensed. However, a place where the detection sensor is formed is not limited to the floor surface.

EXAMPLE

In the example, a transducer using a piezoelectric body is used as the detection sensor10as described below.

An electrode material of the first electrode is an aluminum sheet having a thickness of 12 μm manufactured by Mitsubishi Aluminum Co., Ltd. An intermediate layer of an polymer piezoelectric body is formed by a base material, which is formed by mixing silicone rubber with barium titanate at a ratio of a base rubber of 100 weight % and the barium titanate of 40 weight %, and plaid paint, which is provided to have a target film thickness of about 150±20 μm, a target length of 3 m, and a target width of 150 mm. Here, the silicone rubber is TSE3033 manufactured by Momentive Performance Materials Inc. Further, the barium titanate is 93-5640 manufactured by Wako Pure Chemical Industries, Ltd.

The intermediate layer is sintered for 30 minutes at a high temperature of about 120° C. Thereafter, a surface modification process is performed as a plasma process under the following condition: a device of PR-500 manufactured by YAMATO SCIENTIFIC CO., LTD.; an output of 100 W; a processing time of 4 minutes; an reaction gas of argon 99.999%; and a reaction pressure of 10 Pa.

Further, after the plasma process, a 0.1% liquid solution obtained by diluting OPTOOL DSX, which is a fluorinated carbon compound, manufactured by DAIKIN INDUSTRIES, LTD. by perfluorohexane is painted on the treated surface of the intermediate layer by dipping at a pull-up speed of 10 mm/min. Thereafter, the intermediate layer is maintained in an environment of a humidity of 90% and a temperature of 60° C. for a time equal to or longer than 30 minutes, and thereafter the intermediate layer is dried at 50° C. for ten minutes.

An aluminum sheet layer the same as the material of the first electrode overlaps an upper portion of the intermediate layer to form the second electrode. An electric wire is connected to each electrode, and the entirety is sealed with a PET film having a thickness of 50 μm. At this time, only the electric wires respectively connected to the first and second electrodes are not sealed so as to enable a voltage signal to be taken out. Further, within the example, the following digital signage system is structured.

As the digital signage system, a system illustrated inFIGS. 3A-3Cis structured. The control apparatus20gathering the taken out voltage signals is a personal computer of Vostro 3800, which is manufactured by Dell Computer Corp. and in which Intel Core (“Core” is a registered trademark) i3 processor and an OS of Windows (“Windows” is a registered trademark) 8.1 are installed. The control apparatus20can specify a position by an input signal from the detection sensor10and can estimate a moving speed of a pedestrian from a time change of the former and latter input signals.

The projection apparatus30displaying the advertisement data is three PJ WX4141NI manufactured by Ricoh Co., Ltd. The projection apparatus30is fixed to an upper portion of the projection face102illustrated inFIG. 3. By combining images, an image long along the moving direction of the pedestrian200is projected. Specifically, within the example, based on a calculation performed by the control apparatus20, the advertisement data of preset 5 patterns are switched over at every 0.5 second so as to control a position where the image is displayed, and the advertisement is moved so as to be projected by the projection apparatus30at a position about 30 cm ahead in the moving direction from the pedestrian.

The above digital signage system is evaluated by ten pedestrians, who are randomly selected from walking men, freely walking a walkway having a length of 6 m and a width of 2 m. The walking speeds of the walking men are indicated as in Table 1.

Each of the pedestrians previously selects the curious advertisement from among the advertisements of the five patterns. After the walk, the number of the pedestrians who could watch the corresponding curious advertisement is counted. The counted number is evaluated into 4 levels, namely level1of 0 to 3 persons, level2of 4 to 6 persons, and level3of 7 to 10 persons. Here, the acceptable level is level3.

The evaluation environment includes 3 patterns indicated in Table 2 andFIGS. 11A-11C. Evaluation1of Table 2 andFIG. 11Aindicates a state where predetermined illumination is provided to a projection face102in its vertical direction. Evaluation2of Table 2 andFIG. 11Bindicates a state where, in addition to the environment of evaluation1, an obstacle500is located at a position between 2 m to 4 m from a start point to form a shadow, and an area between the obstacle and the projection face102is walked. Evaluation3of Table 2 andFIG. 11Cindicates a state where, in addition to the environment of evaluation1, the obstacle500is located at a position between 2 m to 4 m from the start point to form the shadow, and it is walked so that the obstacle500is interposed relative to the projection face102(the obstacle500is interposed between the pedestrian and the projection face102).

TABLE 2EVALUATION ENVIRONMENTEVALUATION 1STATE WHERE PREDETERMINEDILLUMINATION IS PROVIDED TO PROJECTIONFACE IN VERTICAL DIRECTION.EVALUATION 2IN ADDITION TO ENVIRONMENT OFEVALUATION 1, OBSTACLE IS LOCATED ATPOSITION BETWEEN 2 m TO 4 m FROM STARTPOINT TO FORM A SHADOW, AND AREABETWEEN OBSTACLE AND PROJECTION FACEIS WALKED.EVALUATION 3IN ADDITION TO ENVIRONMENT OFEVALUATION 1, OBSTACLE IS LOCATED ATPOSITION BETWEEN 2 m TO 4 m FROM STARTPOINT TO FORM A SHADOW, AND IT ISWALKED SO THAT OBSTACLE IS INTERPOSEDRELATIVE TO PROJECTION FACE.

Further, as a comparative example illustrated inFIGS. 12A-12C, instead of the detection sensor10(the transducer), a digital signage system is formed using a position sensing by a camera150, and an evaluation similar to the example is performed. In the comparative example, the frame rate and the resolution of the camera are adjusted so that the processing load of the CPU in the control apparatus20is the same as the example. The image recognition method of the camera is a detection method using a contrast ratio.

The evaluation results are indicated in Tables 3 and 4. In Tables 3 and 4, a mark o designates “visible”, and a mark x designates “invisible”. As described above, the acceptable level is level 3.

From Tables 3 and 4, the following is known. Said differently, from the result of Evaluation1, it is known that the comparative example cannot follow persons (pedestrian (7), pedestrian (8), and pedestrian (9)) walking at a high walking speed to follow unlike the example by which these persons are followed. Therefore, according to the example, sensing is enabled to follow a faster speed than that of the comparative example.

Further, from the result of Evaluation2, it is known that persons (pedestrian (4), pedestrian (5), and pedestrian (6)) walking at a lower walking speed occasionally have a difficulty in viewing the advertisements required to view by these persons. This is caused by an improper display of the advertisement in conformity with the moving speed of the pedestrian. This improper display is caused by an existence of the obstacle in the background of the pedestrian and an insufficient contrast ratio for the camera to recognize the pedestrian due to the obstacle. In the example, such an improper display does not occur. Resultantly, sensing with a lesser environment variation is substantialized in comparison with the comparative example.

Further, from the result of Evaluation3, it is known that persons (pedestrian (1), pedestrian (2), and pedestrian (3)) walking at a further lower walking speed occasionally have a difficulty in viewing the advertisements required to view by these persons. This difficulty is caused by a decrease of a time for the camera to capture the pedestrian by a blind angle and therefore a time for the advertisement to follow the pedestrian is shortened in a case where the pedestrian is once hidden behind the obstacle. Within the example, one person could not view the required advertisement at a speed3. This is physically caused by a decrease of a viewing time for the pedestrian due to the existence of the obstacle. As a result, in comparison with the comparative example, the example substantializes sensing with a fewer blind angle.

As described above, within the embodiment and the example, by using the transducer, which transforms pressure to an electrical signal, as the detection sensor, the position, the weight, and the acceleration of each pressure-sensitive position can be accurately and limitedly acquired. Therefore, the acquired information is positional information as is, and minimally limited data are analyzed. Therefore, the analysis can be conducted using a relatively light process.

Further, in addition to the highly sensitive sensing, it is possible to estimate a movement and a speed of a target person using data of weight movement and acceleration. Therefore, it is possible to follow a faster movement. Furthermore, it is a sensing condition to directly apply pressure to the detection sensor. Therefore, sensing without an environment variation can be structured.

Further, a measurement point is a “surface”, and sensing without a dead angle can be realized by arranging the detection sensors to cover a wide area. As a result, a time for the pedestrian to view the advertisement increases, and therefore a highly appealing advertisement is possible.

According to the embodiment and the example, it is possible to provide a digital signage system having an improved visibility.

This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2015-095079, filed on May 7, 2015, and the Japanese Patent Application No. 2016-012259, filed on Jan. 26, 2016, the entire contents of which are incorporated herein by reference.