close

Вход

Забыли?

вход по аккаунту

?

JP2013187845

код для вставкиСкачать
Patent Translate
Powered by EPO and Google
Notice
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DESCRIPTION JP2013187845
Abstract: To provide a flexible speaker element that can be formed in a large area in order to
realize a non-vibration type thin film speaker. A speaker element according to the present
invention includes a substrate 1, a heat insulating layer 2 formed on a first surface of the
substrate 1 and made of an organic material, and a thin film formed on the heat insulating layer
and generating heat by a drive signal. And the heat generating layer 3 which is [Selected figure]
Figure 1
Speaker element
[0001]
The present invention relates to a speaker device, and more particularly to a flexible speaker
device having a wide frequency characteristic without using mechanical vibration and using
thermoacoustic effect of converting heat energy into sound energy.
[0002]
With the increase in screen size, high definition, and slimness of displays for information display,
thinning of substrates and display elements for displays using ultrathin glass, thin liquid crystals,
organic EL (Electroluminescence) elements, etc. has been promoted.
In recent years, with the aim of realizing a display that is ultra-thin, lightweight, and excellent in
portability and storage, “flexible using an organic semiconductor (organic thin film transistor or
05-05-2019
1
organic EL) that can be formed at a relatively low temperature on a thin plastic film Research on
"display" is accelerating. However, in order to be used as a television display, not only video
output but also audio output is essential, and thin film and flexible speakers are also required.
[0003]
However, the conventional speaker has a mechanical vibration part, and when it is formed
directly on a flexible display, the display itself is super thin and light, so that the vibration of the
speaker causes resonance and the screen shakes. In addition, it is difficult to fabricate a complete
ultra thin film device structurally. If a flexible speaker without mechanical vibration can be
realized, the feasibility of the sheet type large screen television will be greatly enhanced by
making use of its excellent structure.
[0004]
So far, as an example of a non-vibration type sound emitting element, there has been reported a
“heat-induced ultrasonic emitting element” which has no mechanical vibration part and
converts heat rise and fall into compressional waves of air (for example, Non-Patent Document
1). This is, for example, to provide a nanocrystal silicon layer and a surface electrode which are
greatly different in thermal property on a single crystal silicon substrate, and generate a sound
wave by transmitting the magnitude of heat generated by the surface electrode to the air side
(for example, , Patent Document 1).
[0005]
JP, 2005-73197, A
[0006]
Nature Vol. 400, 26 August, pp. 853-855 (1999).
[0007]
However, single crystal silicon is difficult to form in a large area and very hard, so it has the
disadvantage of being fragile when handled.
05-05-2019
2
Furthermore, single crystal silicon is very expensive, and a further price increase is expected in
the future.
[0008]
Therefore, an object of the present invention made in view of such a point is to provide a flexible
speaker element which can be formed in a large area in order to realize a non-vibration type thin
film speaker.
[0009]
In order to solve the various problems described above, the speaker element according to the
present invention is formed on a substrate, a heat insulating layer formed on the first surface of
the substrate and made of an organic material, and the heat insulating layer, and generates heat
by a drive signal. And a heat generating layer which is a thin film.
[0010]
Moreover, it is preferable that the said board | substrate consists of material whose thermal
conductivity is larger than the said heat insulation layer.
[0011]
Further, a second heat insulation layer formed on the second surface of the substrate and made
of an organic material, and a second heat generation layer which is a thin film formed on the
second heat insulation layer and which generates heat according to a drive signal It is preferable
to have.
[0012]
Preferably, a drive circuit is provided for generating the drive signal on the second surface of the
substrate.
[0013]
Moreover, it is preferable that the wiring from the said drive circuit to the said heat-generating
layer penetrates the said board | substrate and the said heat insulation layer, and is formed.
05-05-2019
3
[0014]
According to the present invention, it is possible to provide a flexible speaker element which can
be formed in a large area in order to realize a non-vibration type thin film speaker.
[0015]
It is a figure which shows schematic structure of the speaker element which concerns on one
Embodiment of this invention.
It is a figure which shows the principle of operation of a speaker element.
It is a figure which shows the preparation procedure of a speaker element.
It is a figure which shows the external appearance photograph of the speaker element made as
an experiment.
It is a figure which shows the acoustic characteristic of the speaker element made as an
experiment.
It is a figure which shows the modification of a speaker element.
[0016]
Hereinafter, embodiments of the present invention will be described in detail with reference to
the drawings.
[0017]
FIG. 1 is a view showing a schematic configuration of a speaker element according to an
embodiment of the present invention.
05-05-2019
4
The speaker element includes a substrate 1 as a base, a heat insulating layer 2 formed on the
surface of the substrate 1 and made of an organic material, and a heat generating layer 3 formed
on the heat insulating layer 2 and generating a heat by a drive signal.
Further, as shown, the speaker element can further include an input terminal 4 in order to apply
a drive signal to the heat generating layer 3.
[0018]
The substrate 1 functions as a heat dissipation layer for dissipating a direct current component
of heat generated in the heat generating layer 3 and is, for example, a metal thin film or metal
foil such as aluminum or copper having a thickness of about 0.01 to 1.0 mm, or graphite The
carbon-based thin film of the present invention can be used.
[0019]
The heat insulating layer 2 acts as a heat insulating material for the heat generated in the heat
generating layer 3 and is made of an organic material.
For example, as the organic material constituting the heat insulating layer 2, one having a
dramatically lower thermal conductivity than the substrate 1 may be selected, and the thickness
is variable depending on the sound wave to be emitted, and about 0.001 to 0.1 mm It is suitable.
Many components using organic materials such as general polyimide film or polypropylene film,
polyethylene naphthalate film or polyethylene terephthalate film, olefin resin, fluorine resin,
silicone resin, acrylic resin, etc., are used to constitute the heat insulating layer 2 Film can be
applied.
[0020]
The heat generating layer 3 generates heat by the thermoacoustic effect by generating heat by
the applied drive signal (current / voltage).
05-05-2019
5
Materials constituting the heat generating layer 3 include metal films of aluminum, tungsten,
tantalum, chromium, molybdenum, platinum, gold, silver, copper and the like, transparent
conductive films of indium tin oxide, indium zinc oxide and the like, metal-containing A thin film
of a conductive material is preferable. The thickness is variable depending on the resistance
value of the metal used for the heat generating layer 3 and is preferably about 10 to 100 nm.
[0021]
The input terminal 4 is formed as needed, and when the input terminal 4 is present, the drive
signal can be applied to the heat generating layer 3 through the input terminal 4. When the input
terminal 4 is not provided, the drive signal is directly applied to the heat generating layer 3. The
input terminal 4 can be formed, for example, using the same method and material as the heat
generating layer 3. Further, the thickness is thicker than the heat generating layer 3 in order to
wire the outside, and preferably about 100 to 500 nm.
[0022]
FIG. 2 is a diagram showing the operation principle of the speaker element. When a drive signal
(current / voltage) is applied to the heat generating layer 3, Joule heat is generated in the heat
generating layer 3 and the heat generating layer 3 becomes high temperature. At this time, the
air in contact with the heat generating layer 3 receives thermal energy and expands. For this
reason, by changing the Joule heat generated in the heat generating layer 3 by the drive signal to
be applied to generate compression waves, the speaker element using the thermoacoustic effect
can generate sound.
[0023]
FIG. 2 (a) is a diagram showing an output sound wave in the case where an alternating current
acoustic signal without bias is applied as in a general mechanical vibration speaker. When an AC
acoustic signal without bias is input, heat generation occurs according to the amplitude value of
the AC signal regardless of the sign of the AC signal, so that a sound wave is generated in which
the negative component is folded back to the positive side. That is, for example, when a sine wave
of frequency f is input, a sine wave of double frequency 2f is output.
05-05-2019
6
[0024]
FIG. 2 (b) is a diagram showing an output sound wave in the case where an alternating current
acoustic signal to which bias is applied is applied. When there is a bias, the input signal is limited
to the positive region and heat generation occurs according to the amplitude value of the input
signal. For example, when a sine wave of frequency f is input, a sound wave approximately equal
to frequency f is generated . However, in this case, since a direct current bias always flows
through the heat generating layer 3, there is a problem that the surface temperature of the
speaker element becomes high, and the driving efficiency is lowered.
[0025]
FIG. 3 is a diagram showing a procedure for producing a speaker element. First, the heat
generating layer 3 is formed on the heat insulating layer 2. In this formation, conductive paste,
metal nanoparticle-containing material, and the like can be formed by a printing method in
addition to the conventional vapor deposition method using vacuum film formation and
sputtering method. Further, an adhesion layer may be inserted between the heat insulating layer
2 and the heat generating layer 3 in order to improve the adhesion between the layers. The
material of the adhesion layer is preferably SiO 2 or a polymer film, and the thickness is
preferably 10 to 500 nm. Next, in some cases, the input terminal 4 is formed. By bonding the
heat insulating layer 2 in which these are formed with the substrate 1, a flexible speaker element
can be easily formed. For this bonding, an adhesive such as an acrylic or silicone adhesive or an
epoxy resin can be used. If an adhesive resin is used, only the substrate 1 can be peeled off later
and bonded to another heat insulating layer to be reused as a new speaker element, which is
environmentally superior.
[0026]
FIG. 4 is a view showing an external appearance photograph of a speaker element actually
manufactured on a trial basis. In this trial production, the film thickness is 10 to 10 nm on the
heat insulating layer 2, which is a polyimide film having a film thickness of about 1 micron to 1
mm, by evaporation at a film forming speed of 0.1 to 1 nm / s. The heat generating layer 3 which
is an aluminum thin film of 100 nm is formed, and further, the substrate 1 which is a graphite
sheet having a film thickness of about 10 microns to 1 mm is bonded to the heat insulating layer
2 to form a speaker element. As shown in FIG. 4, the prototyped speaker element is very flexible.
The overall thickness of the speaker element is 0.2 mm or less, which is very thin, and it is also
05-05-2019
7
characterized in that the shape can be processed freely in a planar manner.
[0027]
FIG. 5 is a diagram showing acoustic characteristics of the prototyped speaker element. When a
10 V drive signal (without bias) was applied to the prototyped speaker element, it was confirmed
that a relatively linear sound pressure was output from a low frequency band of 100 Hz to a high
frequency band of more than 10 KHz. That is, the speaker element according to the present
invention is excellent in frequency characteristics, has a wide dynamic range, and is considered
to have a good response due to pulse input.
[0028]
As described above, according to the present embodiment, the speaker element includes the
substrate 1, the heat insulating layer 2 formed on the substrate 1, and the heat generating layer
3 formed on the heat insulating layer 2. In particular, the heat insulating layer 2 consists of an
organic material. Thereby, the speaker element of the present invention becomes a flexible
speaker element which can be formed in a large area, and it becomes possible to realize a nonvibration type thin film speaker.
[0029]
Further, since the substrate 1 is made of a material having a thermal conductivity higher than
that of the heat insulating layer 2, the substrate 1 can more efficiently release the heat generated
by the heat generating layer 3. That is, since the temperature of the entire speaker element
decreases, it is possible to improve the efficiency regarding the sound generation.
[0030]
Although the present invention has been described based on the drawings and examples, it
should be noted that those skilled in the art can easily make various changes and modifications
based on the present disclosure. Therefore, it should be noted that these variations and
modifications are included in the scope of the present invention. For example, the components
05-05-2019
8
included in each component, each step, and the like can be rearranged so as not to contradict
each other logically, and it is possible to combine or divide a plurality of components or steps
into one. It is.
[0031]
For example, FIG. 6A is a view showing an example of a speaker element capable of producing
sound from both sides. In FIG. 6A, in addition to the speaker element shown in FIG. 1, a heat
insulating layer 2 made of an organic material is formed on the back surface of the substrate 1,
and a heat generating layer 3 which is a thin film that generates heat due to a drive signal. Is
formed. Thereby, the speaker element can emit sound waves from both sides. As illustrated, it is
also possible to further form the input terminal 4 on the surface of the heat generating layer 3.
[0032]
Further, FIG. 6B is a view showing an example of a speaker element integrated with the drive
circuit 5. In FIG. 6B, in addition to the speaker element shown in FIG. 1, a drive circuit 5 for
generating a drive signal to be applied to the heat generating layer 3 is formed on the back
surface of the substrate 1. Thereby, a flexible speaker element integrated with the drive circuit 5
can be realized.
[0033]
Further, FIG. 6C is a view showing an example of a speaker element integrated with the drive
circuit 5 and the wiring 6. 6C, in addition to the speaker element shown in FIG. 1, a drive circuit
5 for generating a drive signal to be applied to the heat generating layer 3 is formed on the back
surface of the substrate 1. The wiring 6 is formed to penetrate the substrate 1 and the heat
insulating layer 2. As described above, when the through holes are formed in the substrate 1 and
the heat insulating layer 2 and the drive circuit 5 and the wiring 6 are formed on the back
surface of the substrate 1 and connected to the heat generation layer 3 on the front surface, A
large area can integrate many speaker elements, and the sound pressure can be easily improved.
In addition, since the wires 6 do not extend around, the size of the entire speaker element can be
reduced.
05-05-2019
9
[0034]
According to the present invention, it is possible to easily manufacture a flexible and flexible
speaker element which does not require mechanical vibration with a very simple structure.
[0035]
1 substrate (for example, metal foil, heat conductive film etc.) 2 heat insulation layer (for example
polymer film etc.) 3 heat generation layer (for example aluminum thin film etc.) 4 input terminal
(for example aluminum thin film etc) 5 electric and electronic circuits (for example For example,
a speaker drive circuit, etc. 6 wiring (eg, metal thin film, etc.)
05-05-2019
10
Документ
Категория
Без категории
Просмотров
0
Размер файла
19 Кб
Теги
jp2013187845
1/--страниц
Пожаловаться на содержимое документа