Patent Publication Number: US-2022235928-A1

Title: Heat insulation structure and electronic apparatus

Description:
TECHNICAL FIELD 
     The present technology relates to a heat insulation structure and an electronic apparatus including the heat insulation structure. 
     BACKGROUND ART 
     In an electronic apparatus such as a projection display device, a heat source such as a light source is used, for example. Therefore, a method of reducing an increase in surrounding temperature due to the heat source has been proposed (e.g., PTL 1). 
     CITATION LIST 
     Patent Literature 
     PTL 1: Japanese Unexamined Patent Application Publication No. 2010-139635 
     SUMMARY OF THE INVENTION 
     In such an electronic apparatus, it is desired to suppress the influence of a heat source on its surroundings more effectively. 
     Therefore, it is desirable to provide a heat insulation structure that makes it possible to reduce the influence of a heat source on its surroundings more effectively, and an electronic apparatus including the heat insulation structure. 
     A heat insulation structure according to one embodiment of the present technology includes: a heat source; a heat insulating member surrounding the heat source and having an opening; and a shape retaining member retaining a shape of the heat insulating member. 
     An electronic apparatus according to one embodiment of the present technology includes the heat insulation structure according to one embodiment of the present technology. 
     In the heat insulation structure and the electronic apparatus according to one embodiment of the present technology, the heat insulating member, and the shape retaining member retaining the shape of the heat insulating member are provided. This enables the shape of the heat insulating member to be retained so as to surround the heat source. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic diagram illustrating an exemplary configuration of a light-emitting device according to a first embodiment of the present technology. 
         FIG. 2  (A) is a schematic perspective view of a configuration of a heat insulation structural body illustrated in  FIG. 1 , and (B) is a schematic perspective view of the heat insulation structural body illustrated in (A) together with a light source section. 
         FIG. 3  is a schematic diagram illustrating a cross-sectional configuration along line I-I′ illustrated in (B) of  FIG. 2 . 
         FIG. 4  is a schematic diagram illustrating a planar configuration of the light source section and the heat insulation structural body illustrated in (B) of  FIG. 2 . 
         FIG. 5  is a schematic perspective view of an exemplary configuration of a shape retaining member illustrated in  FIG. 3  and the like. 
         FIG. 6A  is a schematic diagram illustrating an exemplary configuration before a heat insulating member illustrated in  FIG. 3  and the like is wrapped around the shape retaining member. 
         FIG. 6B  is a schematic diagram illustrating a configuration after the heat insulating member illustrated in  FIG. 6A  is wrapped around the shape retaining member. 
         FIG. 7A  is a schematic diagram illustrating another example (1) of the configuration of the heat insulating member illustrated in  FIG. 6A . 
         FIG. 7B  is a schematic diagram illustrating a configuration after the heat insulating member illustrated in  FIG. 7A  is wrapped around the shape retaining member. 
         FIG. 8A  is a schematic diagram illustrating another example (2) of the configuration of the heat insulating member illustrated in  FIG. 6A . 
         FIG. 8B  is a schematic diagram illustrating a configuration after the heat insulating member illustrated in  FIG. 8A  is wrapped around the shape retaining member. 
         FIG. 9  is a diagram illustrating an exemplary configuration of a projection display device to which the light-emitting device illustrated in  FIG. 1  and the like is applied. 
         FIG. 10  is a schematic diagram illustrating an exemplary configuration of a heating device according to a second embodiment of the present disclosure. 
         FIG. 11A  is a schematic diagram illustrating a cross-sectional configuration of a heater and the heat insulation structural body along line II-IT illustrated in  FIG. 10 . 
         FIG. 11B  is a schematic diagram illustrating a planar configuration of the heater and the heat insulation structural body illustrated in  FIG. 10 . 
         FIG. 12  is a plane schematic diagram explaining a configuration of the heater illustrated in  FIG. 10 . 
         FIG. 13A  is a schematic diagram illustrating a cross-sectional configuration along line III-III′ illustrated in  FIG. 12 . 
         FIG. 13B  is a schematic diagram illustrating a cross-sectional configuration along line IV-IV′ illustrated in  FIG. 12 . 
         FIG. 13C  is a schematic diagram illustrating a cross-sectional configuration along line V-V′ illustrated in  FIG. 12 . 
         FIG. 14A  is a diagram explaining a step of manufacturing the heater illustrated in  FIG. 12 . 
         FIG. 14B  is a diagram illustrating a step following  FIG. 14A . 
         FIG. 14C  is a diagram illustrating a step following  FIG. 14B . 
         FIG. 15A  is a diagram illustrating a step following  FIG. 14C . 
         FIG. 15B  is a diagram illustrating a step following  FIG. 15A . 
         FIG. 16  is a diagram illustrating a step following  FIG. 15B . 
         FIG. 17  is a schematic diagram illustrating another exemplary cross-sectional configuration of the heat insulation structural body illustrated in  FIG. 3 . 
         FIG. 18A  is a perspective view of another example (1) of the configuration of the shape retaining member illustrated in  FIG. 5 . 
         FIG. 18B  is a perspective view of another example (2) of the configuration of the shape retaining member illustrated in  FIG. 5 . 
         FIG. 18C  is a perspective view of another example (3) of the configuration of the shape retaining member illustrated in  FIG. 5 . 
     
    
    
     MODES FOR CARRYING OUT THE INVENTION 
     In the following, description is given of embodiments of the present technology in detail with reference to the drawings. The following description is merely a specific example of the present disclosure, and the present disclosure should not be limited to the following embodiments. Moreover, the present disclosure is not limited to arrangements, dimensions, dimensional ratios, and the like of each component illustrated in the drawings. It is to be noted that the description is given in the following order. 
     1. First Embodiment (an example of a light-emitting device in which a heat insulating member is provided around a heat source) 
     1-1. Overall Configuration of Light-Emitting Device 
     1-2. Specific Configuration of Heat Insulation Structural Body 
     1-3. Workings and Effects 
     2. Application Example (an example of a projection display device)
 
3. Second Embodiment (an example of a heating device in which a heat insulating member is provided around a heat source)
 
     3-1. Overall Configuration of Heating Device 
     3-2. Configuration of Heater 
     3-3. Method of Manufacturing Heater 
     3-4. Workings and Effects 
     1. First Embodiment 
     1-1. Overall Configuration of Light-Emitting Device 
       FIG. 1  is a schematic diagram illustrating an exemplary configuration of a light-emitting device (a light-emitting device  10 ) according to a first embodiment of the present technology. The light-emitting device  1  is applied to, for example, a projection display device (e.g., a projection display device  200  in  FIG. 9  to be described later). The light-emitting device  10  includes, for example, an exterior member  11 , a controller  12 , a battery  13 , a light source section  14 , a heat insulation structural body  15 , and a transparent plate  16 . Here, the light source section  14  corresponds to a specific example of a “heat source” of the present technology. 
     The exterior member  11  houses the controller  12 , the battery  13 , the light source section  14 , and the heat insulation structural body  15 . For example, the exterior member  11  has a cylindrical shape. Inside the cylinder, the controller  12 , the battery  13 , the light source section  14 , and the heat insulation structural body  15  are housed. One side (the upper side of the paper surface in  FIG. 1 ) of the exterior member  11  is open, and the transparent plate  16  is provided on this opening. The exterior member  11  includes plastic, for example. Examples of the plastic include ABS (Acrylonitrile Butadiene Styrene) resin, PC (Poly Carbonate)/ABS resin, nylon, and the like. The exterior member  11  may include a metal such as an aluminum alloy (e.g., A1050, A5052), magnesium (Mg), and SUS (Steel Use Stainless). 
     The controller  12  housed in the exterior member  11  is electrically coupled to the battery  13  and the light source section  14 . The controller  12  includes, for example, a wiring board and an IC (Integrated Circuit) mounted on the wiring board. The controller  12  inputs a drive signal to the light source section  14  in response to a signal inputted from the outside, for example. A lighting state of the light source section  14  is controlled in response to the drive signal from the controller  12 . Power is supplied to the controller  12  by the battery  13 . 
     The light source section  14  is lit, by the drive signal inputted from the controller  12 , to generate light. The light source section  14  includes a connector  14 C (illustrated in (B) of  FIG. 2  to be described later) at one end, for example, and is coupled to the controller  12  via the connector  14 C. The light source section  14  includes, for example, a laser, an LED (Light Emitting Diode), or the like. Alternatively, the light source section  14  may include a discharge lamp such as a metal halide lamp, a high-pressure mercury lamp, a halogen lamp, and a xenon lamp. From the light source section  14 , heat is generated with light, for example. Temperature in the vicinity of the light source section  14  may become, for example, about 70° C. to about 300° C. Here, the light source section  14  corresponds to a specific example of the heat source of the present technology. 
     The heat insulation structural body  15  is provided in the vicinity of the light source section  14 . The heat insulation structural body  15  is provided to surround the light source section  14 , and the light generated by the light source section  14  is taken out via an opening (an opening  15 M in (A) of  FIG. 2  to be described later) of the heat insulation structural body  15 . The heat insulation structural body  15  makes the heat generated by the light source section  14  less likely to be transferred to the surroundings, making it possible to suppress an increase in the temperature around the light source section  14 . A specific configuration of the heat insulation structural body  15  will be described later. 
     The transparent plate  16  has a circular planar shape, for example. The transparent plate  16  has, for example, substantially the same size as a circle configuring a bottom surface of the cylindrical exterior member  11 . The opening of the exterior member  11  is closed by the transparent plate  16 . The transparent plate  16  has high transparency to light of a wavelength band generated in the light source section  14 , and the light of the light source section  14  taken out via the opening of the heat insulation structural body  15  is taken out to the outside through the transparent plate  16 . 
     1-2. Specific Configuration of Heat Insulation Structural Body 
     Next, a specific configuration of the heat insulation structural body  15  will be described with reference to  FIGS. 2 to 4 . (A) of  FIG. 2  is a schematic perspective view of the configuration of the heat insulation structural body  15 , and (B) of  FIG. 2  is a perspective view of the configuration of the heat insulation structural body  15  together with the light source section  14 . In (B) of  FIG. 2 , the heat insulation structural body  15  is represented by a broken line.  FIG. 3  illustrates a cross-sectional configuration along line I-I′ in (B) of  FIG. 2 .  FIG. 4  is a plan view of the configuration of the heat insulation structural body  15  together with the light source section  14 . 
     The heat insulation structural body  15  has a cylindrical shape, for example, and has a hole  15 H penetrating from the middle of one bottom surface to the middle of the other bottom surface. In other words, the one bottom surface and the other bottom surface of the heat insulation structural body  15  are provided with the opening  15 M leading to the hole  15 H. The light source section  14  is inserted into the hole  15 H of the heat insulation structural body  15  ((A) and (B) of  FIG. 2 ). That is, the heat insulation structural body  15  configures a side surface of the cylinder, and the light source section  14  is surrounded by the side surface of the cylinder. The light taken out from the one opening  15 M of the heat insulation structural body  15  is emitted via the transparent plate  16 . An air space  18  is interposed between the light source section  14  and the heat insulation structural body  15  ( FIG. 3 ). The heat insulation structural body  15  includes, for example, a shape retaining member  151 , a bonding layer  152 , a heat insulating member  153 , and a fixing member  154 , in order from the hole  15 H (air space  18 ) side. 
       FIG. 5  is a schematic perspective view of an exemplary configuration of the shape retaining member  151 . The shape retaining member  151  is configured to retain a shape of the heat insulating member  153 . For example, the shape of the heat insulating member  153  is formed along an outer shape of the shape retaining member  151 . The shape retaining member  151  has a cylindrical shape, for example, and the shape of the heat insulating member  153  is retained by the sheet-shaped heat insulating member  153  being wrapped around the shape retaining member  151 . The hole  15 H and the opening  15 M of the heat insulation structural body  15  are provided in the shape retaining member  151 . In other words, the shape of the shape retaining member  151  allows the shape of the heat insulation structural body  15  to be adjusted. 
     The shape retaining member  151  includes, for example, a metallic material such as SUS (Steel Use Stainless). The metallic material included in the shape retaining member  151  preferably has a light-reflecting property. By configuring the shape retaining member  151  with a metallic material having a light-reflecting property, the heat generated by the light source section  14  is easily reflected by the shape retaining member  151 . This makes the heat generated by the light source section  14  less likely to be transferred to the outside of the heat insulation structural body  15 . Further, because the metallic material has relatively high stiffness, it is possible to reduce a thickness (a thickness t 151  in  FIGS. 3 to 5 ) of the shape retaining member  151 . The thickness t 151  of the shape retaining member  151  is, for example, 0.5 mm or less. For example, in a case of applying the light-emitting device  10  to a small electronic apparatus, such as a small projection display device, the shape retaining member  151  preferably includes a metal. 
     The shape retaining member  151  may include a resin material, for example. Because the resin material has relatively low heat conductivity, it is possible to improve heat insulation performance of the heat insulation structural body  15 , for example, as compared with the case of configuring the shape retaining member  151  with a metallic material. Further, the resin material is relatively inexpensive. In a case where it is unnecessary to make the heat insulation structural body  15  smaller, for example, in a case of applying the light-emitting device  10  to a large electronic apparatus, the shape retaining member  151  including a resin material is suitably used. 
     The bonding layer  152  is provided, for example, between the shape retaining member  151  and the heat insulating member  153 . For example, the heat insulating member  153  is fixed to the shape retaining member  151  by the bonding layer  152 . The bonding layer  152  includes an adhesive including a resin material, for example. The bonding layer  152  may include a tape or the like. Alternatively, the bonding layer  152  may not be provided between the shape retaining member  151  and the heat insulating member  153 . In this case, the heat insulating member  153  is fixed to the shape retaining member  151  by the fixing member  154 . 
     The heat insulating member  153  bonded to the shape retaining member  151  via the bonding layer  152  has a heat conductivity of 0.04 W/m·k or less, for example, under a 20° C. environment. The heat insulating member  153  makes the heat generated by the light source section  14  less likely to be transferred to the outside of the heat insulation structural body  15 . That is, the heat insulating member  153  mainly serves a heat insulation function in the heat insulation structural body  15 . In the present embodiment, the heat insulating member  153  is retained in a shape surrounding the light source section  14  by the shape retaining member  151 . As will be described in detail later, this makes it possible to suppress the influence of the light source section  14  on its surroundings more effectively. 
     The heat insulating member  153  has a sheet-shape, for example, and is disposed to follow the outer shape of the shape retaining member  151 . That is, the heat insulating member  153  continuously surrounds the light source section  14  by the side surface of the cylinder. The heat insulating member  153  is provided with the opening (the opening  15 M of the heat insulation structural body  15 ) at a position corresponding to the bottom surface of the cylinder. That is, the heat insulating member  153  has a pair of openings opposed to each other with the light source section  14  therebetween. The light generated by the light source section  14  is taken out via one of the pair of openings. Providing the heat insulating member  153  with such an opening makes the light generated by the light source section  14  available, which enhances the flexibility in arrangement of parts. 
     The heat insulating member  153  has a thickness (a thickness t 153  in  FIGS. 3 and 4 ) of, for example, 5.0 mm or less. In particular, in a case of applying the light-emitting device  10  to a small electronic apparatus, it is preferable that the thickness t 153  of the heat insulating member  153  be 5.0 mm or less, because a gap between the parts is also reduced. In a case where the temperature of the light source section  14  is 300° C. or less, the heat insulating member  153  with the thickness t 153  of 2.0 mm or less may be used. For example, the heat insulating member  153  may be configured by overlapping a plurality of sheets having a thickness of about 0.1 mm. Configuring the heat insulating member  153  by overlapping a plurality of sheets makes it easier to adjust the thickness t 153  of the heat insulating member  153 . 
     The sheet-shaped heat insulating member  153  has an end face  153 E ( FIG. 3 ) on one opening side and the other opening side. For example, the end face  153 E on the one opening side is exposed to be in contact with the air. As will be described in detail later, it is easy to make the heat insulation structural body  15  smaller, because the heat insulating member  153  is not made airtight in the heat insulation structural body  15 . The end face  153 E may be covered with another member, for example, or may be coated with a resin material or the like. 
       FIG. 6A  illustrates a configuration of the end face  153 E of the heat insulating member  153  in a state before being wrapped around the shape retaining member  151 .  FIG. 6B  illustrates a configuration of the cylindrical shape retaining member  151  and the heat insulating member  153  wrapped around the shape retaining member  151 . The end face  153 E of the heat insulating member  153  has an inner peripheral side Si provided on the shape retaining member  151  side, and an outer peripheral side So provided on the fixing member  154  side. When the heat insulating member  153  is wrapped around the shape retaining member  151 , both sides in an extending direction (X-axis direction) of the end face  153 E meet (a meeting portion A). For example, the end face  153 E of the heat insulating member  153  may be substantially trapezoidal. In this case, for example, the inner peripheral side Si is substantially the same size as the circumference of the cylindrical shape retaining member  151 , and the outer peripheral side Si is larger than the inner peripheral side Si. This makes it easier to wrap the heat insulating member  153  around the shape retaining member  151 . 
       FIGS. 7A and 8A  illustrate other examples (other examples (1) and (2)) of the configuration of the end face  153 E of the heat insulating member  153  illustrated in  FIG. 6A .  FIGS. 7B and 8B  illustrate other examples (other examples (1) and (2)) of the configuration of the heat insulating member  153  illustrated in  FIG. 6B . As illustrated in  FIG. 7A , the end face  153 E of the heat insulating member  153  may substantially be a parallelogram. In this case, for example, the meeting portion A is formed to deviate from a diametrical direction of the shape retaining member  151 , as illustrated in  FIG. 7B . Alternatively, the end face  153 E of the heat insulating member  153  may be rectangular (not illustrated). Further, as illustrated in  FIG. 8A , a slit  153 L may be provided on the heat insulating member  153  in a direction from the outer peripheral side So toward the inner peripheral side Si. By providing the slit  153 L, the slit  153 L expands on the outer peripheral side So ( FIG. 8B ) when the heat insulating member  153  is wrapped around the shape retaining member  151 , making it possible to reduce stress on the outer peripheral side So side. This makes it easier to wrap the heat insulating member  153  around the shape retaining member  151 . The slit  153 L has a depth that is, for example, about ⅓ of the thickness t 153  of the heat insulating member  153 . For example, three slits  153 L are provided on the heat insulating member  153 . 
     The heat insulating member  153  preferably includes an aerogel, for example. Examples of the aerogel include silica aerogel. The heat insulating member  153  including the aerogel has excellent heat insulation performance. Further, the heat insulating member  153  including the aerogel reduces most of the three influences of convection, radiation, and heat conductivity. Such a heat insulating member  153  is easily reduced in its thickness t 153 . Therefore, the heat insulating member  153  including the aerogel may be suitably used for a small electronic apparatus. 
     The air space  18  is provided between the heat insulating member  153  and the light source section  14 , specifically, between the shape retaining member  151  and the light source section  14 . The air space  18  also provides heat insulation. Therefore, providing the air space  18  between the heat insulating member  153  and the light source section  14  makes it easier to adjust a heat resistance temperature of the heat insulating member  153 . For example, the air space  18  is adjusted to a predetermined size by performing positioning between the shape retaining member  151  and the light source section  14 . 
     The light-emitting device  1  includes, for example, a locking member  17  configured to perform positioning between the heat insulation structural body  15  and the light source section  14 , specifically, positioning between the shape retaining member  151  and the light source section  14  ( FIG. 3 ). The locking member  17  is an annular member, for example, and is mounted in a flanged shape on the light source section  14  ((B) of  FIG. 2 ). For example, the position of the heat insulation structural body  15  with respect to the light source section  14 , i.e., the position of the heat insulating member  153  with respect to the light source section  14 , is fixed by a projection  17 P, provided on the inner periphery of the locking member  17 , catching the shape retaining member  151  from the other opening  15 M of the heat insulation structural body  15 . The locking member  17  preferably includes a material having a low heat conductivity, and includes, for example, a resin material or the like with a heat conductivity of 1.0 W/m·k or less. Examples of such a resin material include engineering plastics such as PEEK (polyether ether ketone) and PPS (polyphenylene sulfide). Here, a portion where the projection  17 P and the shape retaining member  151  contact each other corresponds to a specific example of a positioning section of the present technology. Positioning of the heat insulating member  153  with respect to the light source section  14  may be performed by another method. For example, a recess may be provided on the locking member  17 , a projection may be provided on the shape retaining member  151 , and the recess and the projection may be fitted together. 
     The fixing member  154  is configured to fix the heat insulating member  153  to the shape retaining member  151 . For example, the outer periphery of the heat insulating member  153  is supported by the fixing member  154 . A shrinkable tube may be used, for example, for the fixing member  154 . In this case, the heat insulating member  153  is fixed to the shape retaining member  151  by shrinkage force of the shrinkable tube. For example, when the heat insulating member  153  is wrapped around the shape retaining member  151 , the thickness of the heat insulating member  153  at the meeting portion A (e.g.,  FIG. 7B  and the like) may be larger than the thickness of the heat insulating member  153  at another portion. In this case, by using the shrinkable tube for the fixing member  154 , it is possible to compress the thickness of the heat insulating member  153  at the meeting portion A to the same extent as the thickness of the heat insulating member  153  at the other portion. The fixing member  154  may be, for example, a pipe-shaped part covering the outer periphery of the heat insulating member  153 . For example, the fixing member  154  may include a pipe of a metal such as stainless steel. Alternatively, the fixing member  154  may be a tape including a resin material such as polyimide. On the fixing member  154 , aluminum (Al) or the like may be deposited, for example. This makes it possible to reduce emissivity of heat from the heat insulation structural body  15 . 
     1-3. Workings and Effects 
     The heat insulation structural body  15  included in the light-emitting device  10  of the present embodiment is provided with the heat insulating member  153 , and the shape retaining member  151  retaining the shape of the heat insulating member  153 . This enables the shape of the heat insulating member  153  to be retained so as to surround the light source section  14 . 
     For example, in a case where the shape retaining member is not provided in the heat insulation structural body, it is difficult to freely adjust the shape of the sheet-shaped heat insulating member. Therefore, the heat insulating member is disposed only in one direction of the heat source, and an increase in temperature caused by the heat source is likely to occur in a direction other than the direction in which the heat insulating member is provided. Therefore, parts with low heat resistance have to be disposed sufficiently away from the heat source. Such a heat insulation structural body without a shape retaining member is difficult to apply to a small device. 
     Also conceivable are a method of performing heat insulation by evacuating the inside of an airtight container, and a method of performing heat insulation by filling the airtight container with an aerogel. The airtight container has, for example, an inner wall on the heat source side, an outer wall opposed to the inner wall, and a connection portion coupling the inner wall and the outer wall. Such an airtight container involves a concern that, when heat is transferred from the heat source to the inner wall, this heat is transferred to the outer wall via the connection portion, i.e., the concern of a heat bridge structure. In the heat bridge structure, in order to perform sufficient heat insulation, it is necessary to radiate heat by making a heat transfer path longer. This makes the airtight container larger. Therefore, a heat insulation structural body with such an airtight container is also difficult to apply to a small device. In particular, an airtight container for retaining the vacuum state includes a material having high heat conductivity, which tends to make the airtight container larger. A metallic material, a glass material, or the like is often used for the airtight container for retaining the vacuum state in order to suppress transmission of gas therethrough. 
     Such an airtight container is unnecessary in a case of using a foamed resin such as urethane foam and melamine foam as the heat insulating member. However, such a heat insulating member is intended mainly to prevent convective heat transfer, which tends to make the heat insulating member thicker. Therefore, such a heat insulating member including a foamed resin is also difficult to apply to a small device. 
     In contrast, the heat insulation structural body  15  of the light-emitting device  1  includes the shape retaining member  151 , which makes it possible to retain the shape of the heat insulating member  153  so as to surround the light source section  14 . Therefore, the vicinity of the light source section  14  is heat-insulated more effectively, as compared with the case of providing the heat insulating member  153  in only one direction of the light source section  14 . This makes it possible to suppress the influence of the light source section  14  on its surroundings more effectively, allowing even parts with low heat resistance to be disposed closer to the light source section  14 . That is, the heat insulation structural body  15  may be suitably used for a small device. Further, by the heat insulation structural body  15  including the shape retaining member  151 , it is easy to maintain the dimensions of the heat insulating member  153  stably. 
     Furthermore, in the heat insulation structural body  15 , one end face  153 E of the heat insulating member  153  is exposed. That is, the heat insulation structural body  15  does not have the heat bridge structure, and it is unnecessary to make the heat transfer path longer. This makes it easier to make the heat insulation structural body  15  smaller and apply it to a small device. Further, because such a heat insulation structural body  15  is manufactured under normal temperature and normal pressure, it may be easily manufactured as compared with a heat insulation structural body that evacuates the inside of an airtight container. 
     Further, because the heat insulating member  153  of the heat insulation structural body  15  includes an aerogel, it is easily reduced in its thickness t 153 , as compared with the heat insulating member  153  including a foamed resin. Therefore, the use of the aerogel for the heat insulating member  153  makes the heat insulation structural body  15  smaller and easier to apply to a small device. 
     As described above, in the present embodiment, the heat insulating member  153  is provided to surround the light source section  14 . This enables the vicinity of the light source section  14  to be heat-insulated more effectively, as compared with the case of providing the heat insulating member only in one direction of the heat source. This makes it possible to suppress the influence of the light source section  14  on its surroundings more effectively. Such a heat insulation structural body  15  makes it easier to dispose parts in the vicinity of the light source section  14 , and therefore is suitably used for a small device. 
     Further, in the light-emitting device  10  including such a heat insulation structural body  15 , the designing flexibility of parts is enhanced. For example, it is possible to use a part including a resin with low heat resistance in the vicinity of the light source section  14 . This makes it possible to suppress cost for the parts. 
     2. Application Example 
     The light-emitting device  10  described in the first embodiment may be applied, for example, to an electronic apparatus such as a projection display device. 
       FIG. 9  is a diagram illustrating an exemplary configuration of a projection display device (the projection display device  200 ) to which the light-emitting device  10  is applied. The projection display device  200  is, for example, a display device that projects an image on a screen. The projection display device  200  is coupled, via an I/F (interface), to a computer such as a PC or an external image supplying device such as various image players, for example, and performs projection on a screen or the like on the basis of an image signal inputted to the I/F. Note that the configuration of the projection display device  200  described below is an example. The projection display device according to the present technology is not limited to such a configuration. 
     The projection display device  200  includes the light-emitting device  10 , a multi-lens array  212 , a PbS array  213 , a focus lens  214 , a mirror  215 , dichroic mirrors  216  and  217 , optical modulators  218   a  to  218   c , a dichroic prism  219 , and a projection lens  220 . 
     In the light-emitting device  10 , light emitted from a light-emitting element  121  passes through an array lens, and is taken out as collimating light. The light enters the multi-lens array  212 . The multi-lens array  212  has a structure in which a plurality of lens elements are provided in an array, and condenses the light emitted from light-emitting devices  1  and  2 . The PbS array  213  polarizes the light condensed by the multi-lens array  212  into light in a predetermined polarization direction, for example, P-polarized waves. The focus lens  214  condenses the light that has been converted into light in the predetermined polarization direction by the PbS array  213 . 
     The dichroic mirror  216  transmits red light R, and reflects green light G and blue light B, of the light that has entered via the focus lens  214  and the mirror  215 . The red light R transmitted by the dichroic mirror  216  is guided to the optical modulator  218   a  via the mirror  215 . 
     The dichroic mirror  217  transmits the blue light B and reflects the green light G, of the light reflected by the dichroic mirror  216 . The green light G reflected by the dichroic mirror  217  is guided to the optical modulator  218   b . On the other hand, the blue light B transmitted by the dichroic mirror  217  is guided to the optical modulator  218   c  via the mirror  215 . 
     Each of the optical modulators  218   a  to  218   c  optically modulates the colored light beam that has entered, and causes the optically-modulated colored light beam to enter the dichroic prism  219 . The dichroic prism  219  combines, into one optical axis, the colored light beams that have entered after being optically modulated. The combined colored light beams are projected onto a screen or the like via the projection lens  220 . 
     In the projection display device  200 , the three optical modulators  218   a  to  218   c  corresponding to three colors of red, green, and blue, which are three primary colors, are combined, and all colors are displayed. That is, the projection display device  200  is a so-called three-chip projection display device. 
     Next, a second embodiment of the present disclosure will be described. In the following description, the same components as those in the first embodiment are denoted with the same reference numerals, and descriptions thereof are omitted as appropriate. 
     3. Second Embodiment 
     3-1. Overall Configuration of Heating Device 
       FIG. 10  is a schematic diagram illustrating an exemplary configuration of a light-emitting device (a heating device  20 ) according to the second embodiment of the present technology. The heating device  20  is applied, for example, to an aroma diffuser, an electronic aroma furnace, and the like. The heating device  20  includes a heater  24 , for example, and in addition, includes the exterior member  11 , the controller  12 , the battery  13 , and the heat insulation structural body  15 , as in the first embodiment. Further, the opening of the exterior member  11  is closed by a cap  19 . Here, the heater  24  correspond to a specific example of the “heat source” of the present technology. 
     The cap  19  has a circular planar shape, for example. The cap  19  has, for example, substantially the same size as the circle configuring the bottom surface of the cylindrical exterior member  11 . The opening of the exterior member  11  is closed by the cap  19 . The cap  19  includes plastic, for example. Examples of the plastic include ABS (Acrylonitrile Butadiene Styrene) resin, PC (Poly Carbonate)/ABS resin, nylon, and the like. The cap  19  may include a metal such as an aluminum alloy (e.g., A1050, A5052), magnesium (Mg), and SUS (Steel Use Stainless). 
     The heater  24  generates heat by being applied with a current from the battery  13 , for example, in response to a control signal inputted from the controller  12 . Although a detailed configuration of the heater  24  will be described later, the heater  24  has a sheet-shape, for example, and includes a heat generator  240 X and a connector  240 Y. To the connector  240 Y, a wiring line  251  electrically coupled to a pair of electrodes of the battery  13 , for example, is coupled via solder  260  (see  FIG. 12 ). 
     In the present embodiment, the heater  24  forms a cylindrical shape, for example, and has a hole  24 H penetrating from one bottom surface to the other bottom surface. In other words, the one bottom surface and the other bottom surface of the heater  24  are provided with an opening  24 M leading to the hole  24 H. 
     Next, a specific configuration of the heater  24  and the heat insulation structural body  15  will be described with reference to  FIGS. 11A and 11B . In the heating device  20 , the heater  24  serving as a heat source is disposed between the shape retaining member  151  and the heat insulating member  153  included in the heat insulation structural body  15 , and the shape of the heater  24  is formed along an outer diameter of the shape retaining member  151 . The shape retaining member  151  has a cylindrical shape, for example, as in the first embodiment, and the shape of the heater  24  is retained by the sheet-shaped heater  24  being wrapped around the shape retaining member  151 . The heat insulating member  153  is provided around the heater  24 . Specifically, the bonding layer  152  is provided, for example, between the heater  24  and the heat insulating member  153 , and the heat insulating member  153  is fixed to the heater  24  by the bonding layer  152 . Alternatively, the bonding layer  152  may not be provided between the heater  24  and the heat insulating member  153 . In this case, the heat insulating member  153  is fixed to the heater  24  by the fixing member  154 . That is, the heater  24  and the heat insulating member  153  are in contact with each other directly or via the bonding layer  152 . 
     Note that an aerogel incorporated with fluororesin, melamine resin, or silicone, for example, is preferably used for the heat insulating member  153  of the present embodiment. This makes it possible to improve the heat resistance of the heat insulating member  153 . Further, one bottom surface of the heat insulation structural body  15  may be provided with a cap or the like that closes the opening  24 M. The cap may be integrated with the heat insulation structural body  15  or may be formed separately. 
     3-2. Configuration of Heater 
       FIG. 12  is a schematic diagram illustrating an exemplary planar configuration of the heater  24 .  FIG. 13A  is a cross-sectional schematic diagram illustrating the heater  24  along line III-III′ illustrated in  FIG. 12 .  FIG. 13B  is a cross-sectional schematic diagram illustrating the heater  24  along line IV-IV′ illustrated in  FIG. 12 .  FIG. 13C  is a cross-sectional schematic diagram illustrating the heater  24 , more precisely, the wiring line  251  coupled to the heater  24 , along line V-V′ illustrated in  FIG. 12 . 
     The heater  24  is a sheet-shaped heating element including the heat generator  240 X and the connector  240 Y as described above. The heater  24  has a configuration in which an electrically-conductive film  242  is patterned on a flexible substrate  241 . Specifically, the electrically-conductive film  242  includes, for example, a plurality of electrically-conductive films  242 A,  242 B, and  242 C that are independent of each other, and expanded portions  242 D 1  and  242 D 2  in which the electrically-conductive films  242 A,  242 B, and  242 C are integrated at their respective one ends and other ends. The plurality of electrically-conductive films  242 A,  242 B, and  242 C that are independent of each other are patterned to be parallel to each other, for example. The plurality of electrically-conductive film  242 A,  242 B, and  242 C portions that are independent of each other configure the heat generator  240 X, and the expanded portions  242 D 1  and  242 D 2  configure the connector  240 Y. To the connector  240 Y, a pair of wiring lines  251  ( 251 A and  251 B) are joined via the solder  260 . 
     The flexible substrate  241  is a support substrate having flexibility, and includes an insulating material such as polyimide (PI) resin, for example. 
     The electrically-conductive film  242  is preferably formed using an electrically-conductive material having relatively high electric resistance, for example. Examples of such an electrically-conductive material include a metallic material such as SUS (Steel Use Stainless), carbon, and the like. In the heat generator  240 X, the electrically-conductive film  242  becomes hot by energization, because it is patterned as the plurality of electrically-conductive films  242 A,  242 B, and  242 C independent of each other. On the other hand, in the connector  240 Y, the electrically-conductive film  242  configures the expanded portions  242 D 1  and  242 D 2  wider than the electrically-conductive films  242 A,  242 B, and  242 C by integrating the electrically-conductive films  242 A,  242 B, and  242 C. Therefore, the electric resistance is smaller as compared with the electrically-conductive film  242 A,  242 B, and  242 C portions. That is, the temperature of the connector  240 Y when energized is maintained at a lower temperature than the heat generator  240 X. 
     Note that the electrically-conductive film  242  of the present embodiment is partly patterned to have slits to thereby include the plurality of independent electrically-conductive films  242 A,  242 B, and  242 C. The individual patterns are thus made narrow. However, it does not necessarily have to be a plurality of electrically-conductive films, and may be formed using one narrow electrically-conductive film. In other words, one electrically-conductive film may be used if the electrically-conductive film in the heat generator  240 X continuous from the electrically-conductive film in the connector  240 Y is narrow. Further, it is unnecessary for the electrically-conductive film of the heat generator  240 X and the electrically-conductive film of the connector  240 Y to have the same width at the connection portion. For example, narrow electrically-conductive films may extend in different directions from an end of the connector  240 Y. 
     The pair of wiring lines  251  ( 251 A and  251 B) are copper (Cu) wiring lines, for example, having a flat-plate shape. One ends of the wiring lines  251 A and  251 B are electrically coupled respectively to the expanded portions  242 D 1  and  242 D 2 , and the other ends are electrically coupled respectively to, for example, the pair of electrodes of the battery  13 . As illustrated in  FIG. 13C , the wiring lines  251 A and  251 B are, for example, covered with an insulating film  252  including epoxy resin, silicone resin, fluororesin, or the like, except for the connection portion with the expanded portions  242 D 1  and  242 D 2 , for example. Note that  FIGS. 12 and 13C  illustrate an example in which the wiring lines  251 A and  251 B are collectively covered with the insulating film  252 , but they may be covered separately. 
     In the connector  240 Y, as illustrated in  FIG. 13B , the expanded portion  242 D 1 , the solder  260 , and the wiring line  251 A are stacked in this order, and the expanded portion  242 D 2 , the solder  260 , and the wiring line  251 B are stacked in this order, on the flexible substrate  241 . That is, the expanded portion  242 D 1  and the wiring line  251 A are joined together via the solder  260 , and the expanded portion  242 D 2  and the wiring line  251 B are joined together via the solder  260 . As the solder  260 , solder such as SnCuNiGe (tin-copper-nickel-germanium) alloy may be used, for example. In addition, SnAgCu (tin-silver-copper)-based, AuSn (gold-tin)-based, Sn (tin)-based, or In (indium)-based solder may be used, for example. 
     3-3. Method of Manufacturing Heater 
     The heater  24  may be manufactured as follows, for example. First, as illustrated in  FIG. 14A , the electrically-conductive film  242  is formed on the flexible substrate  141 . Subsequently, as illustrated in  FIG. 14B , a photoresist is applied onto the electrically-conductive film  242 , for example. Then, pre-bake, exposure, development, and post-bake are obtained to form a resist film having a predetermined pattern. Then, the electrically-conductive film  242  having a predetermined pattern is formed by etching, for example. Next, as illustrated in  FIG. 14C , the electrically-conductive film  242  except for a portion (e.g., the expanded portions  242 D 1  and  242 D 2 ) is covered by an insulating film  243  including epoxy resin, silicone resin, or fluororesin, for example. 
     In parallel with this, the wiring line  251  to be joined to the electrically-conductive film  242  is prepared. First, as illustrated in  FIG. 15A , the wiring lines  251 A and  251 B covered with the insulating film  252  are prepared. Subsequently, as illustrated in  FIG. 15B , a portion of the insulating film  252  is removed to expose the ends of the wiring lines  251 A and  251 B. Next, as illustrated in  FIG. 16 , the solder  260  in the form of a metallic foil or a paste is applied to the electrically-conductive film  242 , for example, and heated at a temperature several tens of degrees higher than a melting temperature of the solder  260 . Thus, the wiring lines  251 A and  251 B are joined to the electrically-conductive film  242 . Thereafter, the heater  24  illustrated in  FIG. 12  is completed by covering the surroundings of the junction by an insulating film. 
     Note that the joining of the expanded portions  242 D 1  and  242 D 2  and the wiring lines  251 A and  251 B in the connector  240 Y illustrated in  FIG. 12  is preferably performed at a position as far away as possible from the heat generator  240 X. Specifically, it is preferable to join them at a position away from the edge of the heat generator  240 X by about 2 mm to about 3 mm, for example. This makes it possible to prevent a decrease in joining strength between the expanded portions  242 D 1  and  242 D 2  and the wiring lines  251 A and  251 B due to heat transfer from the heat generator  240 X. 
     3-4. Workings and Effects 
     In the heating device  20  of the present embodiment, the heater  24  having a sheet shape is used as a heat source. The heater  24  is disposed, for example, along the outer diameter of the shape retaining member  151  having a cylindrical shape. Around the heater  24  is provided the heat insulating member  153  directly or via the bonding layer  152 . This enables the heat generated by the heater  24  to be efficiently stored inside the heat insulation structural body  15 , specifically, inside the hole  24 H of the heater  24  forming a cylindrical shape. Therefore, in addition to the effects of the first embodiment, power saving of the heating device  20  is enabled. 
     Further, in steps of manufacturing a typical heater, an electrically-conductive film to be a heating element is patterned, and then is copper-plated at a predetermined position to reduce an electric resistance value of the electrically-conductive portion. This plating step is a cause of an increase in manufacturing cost. 
     In contrast, in the heater  24  of the present embodiment, at the one ends and the other ends of the plurality of electrically-conductive films  242 A,  242 B, and  242 C configuring the heat generator  240 X, the expanded portions  242 D 1  and  242 D 2  in which the plurality of electrically-conductive films  242 A,  242 B, and  242 C are integrated are provided. These are used as the connector  240 Y with the pair of wiring lines  251 A and  251 B that apply a current to the plurality of electrically-conductive films  242 A,  242 B, and  242 C. This enables the temperature of the connector  240 Y when energized to be maintained at a temperature lower than the melting point of the solder, for example, which enables the solder joining of the electrically-conductive film  242  (the expanded portions  242 D 1  and  242 D 2 ) and the wiring line  251  ( 251 A and  251 B). Therefore, it is possible to reduce the manufacturing cost of the heater  24  and the heating device  20  including the heater  24 . 
     Further, wiring lines having a flat-plate shape are used as the pair of wiring lines  251 A and  251 B. This results in an increase in joining area between the electrically-conductive film  242  (the expanded portions  242 D 1  and  242 D 2 ) and the wiring lines  251 A and  251 B in the connector  240 Y, making it possible to improve the joining strength. Therefore, it is possible to improve reliability. 
     Although the present technology has been described above with reference to the first and second embodiments and the application example, the present technology is not limited to the above embodiments, and various modifications may be made. For example, the components, arrangement, and the like of the light-emitting device  10  and the heating device  20  exemplified in the above embodiments and the like are merely examples. It is unnecessary to include all the components, and other components may be further included. 
     Further, although the above embodiments and the like describe the case where the light-emitting device  10  and the heating device  20  include the heat insulation structural body  15 , the heat insulation structural body  15  may be provided in another electronic apparatus. 
     Further, for example, the first embodiment describes an example in which the heat insulation structural body  15  includes the shape retaining member  151 , the bonding layer  152 , the heat insulating member  153 , and the fixing member  154 , in order from a position close to the light source section  14  (the hole  15 H). However, the heat insulation structural body  15  may have another configuration. For example, as illustrated in  FIG. 17 , the heat insulating member  153  may be provided between the light source section  14  and the shape retaining member  151 . That is, the shape retaining member  151  may be disposed on the outside of the heat insulating member  153 . Further, the shape retaining member  151  may include a resin, for example. A resin has a smaller specific heat and specific gravity than a metal. That is, its heat capacity is smaller. Providing the shape retaining member  151  with a relatively low heat capacity at a position close to the heat source (the light source section  14 ) makes it easier to store heat inside the heat insulation structural body  15 . 
     Further, although  FIG. 5  illustrates an exemplary configuration of the shape retaining member  151 , the shape retaining member  151  may have another configuration.  FIGS. 18A, 18B , and  18 C illustrate other examples (other examples (1), (2), and (3)) of the configuration of the shape retaining member  151  illustrated in  FIG. 5 . The shape retaining member  151  may thus be provided with a bored portion  151 A. The bored portion  151 A is a portion in which the metal, resin, or the like included in the shape retaining member  151  is partly bored. The bored portion  151 A may have, for example, any shape such as a circle, an ellipse, or a square. Bored portions  151 A with small size may be scattered throughout the shape retaining member  151  ((A) of  FIG. 18 ), or one or two bored portions  151 A may be provided to extend in a length direction of the cylinder ((B) and (C) of  FIG. 18 ). The bored portion  151 A may be disposed in any way. The weight of the shape retaining member  151  is reduced by providing the shape retaining member  151  with the bored portion  151 A. Therefore, the heat capacity of the shape retaining member  151  is reduced. Such a shape retaining member  151  enables heat to be easily stored inside the heat insulation structural body  15 , and is suitably used for the heating device  20  used as, for example, an aroma diffuser or the like. 
     Further, although the above embodiments and the like describe an example in which the shape retaining member  151  has a cylindrical shape, the shape retaining member  151  may have another shape. For example, the shape retaining member  151  may have a tubular shape such as a prism shape. 
     Further, although the above embodiments and the like describe an example in which the heat insulating member  153  continuously surrounds the light source section  14 , the heat insulating member  153  separated into a plurality of pieces may surround the light source section  14 . Alternatively, the opening of the heat insulating member  153  may be provided on the side surface of the cylinder. 
     Further, although the first embodiment describes the case of performing the positioning of the heat insulation structural body  15  by using the locking member  17 , the positioning with the heat insulation structural body  15  may be performed by another method. For example, the heat insulation structural body  15  may be fixed to the exterior member  11 , a chassis, or the like. 
     It is to be noted that the effects described in this specification are merely illustrative and non-limiting, and other effects may be provided. 
     It is to be noted that the present technology may have the following configurations. According to the heat insulation structure and the electronic apparatus of the present technology having the following configurations, the heat insulating member  153  is provided to surround the light source section  14 . This enables the vicinity of the light source section  14  to be heat-insulated more effectively, as compared with the case of providing the heat insulating member only in one direction of the heat source. This makes it possible to suppress the influence of the light source section  14  on its surroundings more effectively. 
     (1) 
     A heat insulation structure including: 
     a heat source; 
     a heat insulating member surrounding the heat source and having an opening; and a shape retaining member retaining a shape of the heat insulating member. 
     (2) 
     The heat insulation structure according to (1), in which the heat insulating member includes an aerogel. 
     (3) 
     The heat insulation structure according to (1) or (2), in which the opening includes a first opening and a second opening opposed to each other with the heat source therebetween. 
     (4) 
     The heat insulation structure according to any one of (1) to (3), in which the heat insulating member has a sheet shape. 
     (5) 
     The heat insulation structure according to any one of (1) to (4), in which an end face of the heat insulating member is exposed. 
     (6) 
     The heat insulation structure according to any one of (1) to (5), in which the shape retaining member has a tubular shape. 
     (7) 
     The heat insulation structure according to any one of (1) to (6), in which the shape retaining member includes a metal. 
     (8) 
     The heat insulation structure according to any one of (1) to (7), in which the shape retaining member has a light-reflecting property. 
     (9) 
     The heat insulation structure according to any one of (1) to (8), in which 
     the heat source has a sheet shape, and 
     the heat source and the heat insulating member are provided in this order around the shape retaining member. 
     (10) 
     The heat insulation structure according to any one of (1) to (9), further including a fixing member that fixes the heat insulating member to the shape retaining member. 
     (11) 
     The heat insulation structure according to (10), in which 
     the fixing member includes a shrinkable tube, and 
     the heat source and the heat insulating member are provided between the fixing member and the shape retaining member. 
     (12) 
     The heat insulation structure according to any one of (1) to (8), in which the heat insulating member surrounds the heat source via an air space. 
     (13) 
     The heat insulation structure according to (12), in which the shape retaining member is provided between the air space and the heat insulating member. 
     (14) 
     The heat insulation structure according to (12) or (13), further including a fixing member that fixes the heat insulating member to the shape retaining member, in which 
     the fixing member includes a shrinkable tube, and 
     the heat insulating member is provided between the fixing member and the air space. 
     (15) 
     The heat insulation structure according to any one of (1) to (14), further including a positioning section configured to determine a position of the heat insulating member with respect to the heat source. 
     (16) 
     The heat insulation structure according to any one of (1) to (15), in which the heat insulating member continuously surrounds the heat source. 
     (17) 
     An electronic apparatus including a heat insulation structure, 
     the heat insulation structure including
         a heat source,   a heat insulating member surrounding the heat source and having an opening, and   a shape retaining member retaining a shape of the heat insulating member.
 
(18)
       

     A heating element including: 
     a heat generator including an electrically-conductive film having a first width; 
     a connector including a pair of expanded portions in which one end and the other end of the electrically-conductive film are integrated with each other, the pair of expanded portions having a second width wider than the first width; and 
     a pair of wiring lines having a flat-plate shape and joined to the pair of connectors via solder. 
     (19) 
     The heating element according to (18), in which the heat generator includes a plurality of the electrically-conductive films having the first width and extending from the expanded portion. 
     (20) 
     The heating element according to (18) or (19), in which the electrically-conductive film included in the heat generator and the connector, and the pair of wiring lines include electrically-conductive materials different from each other. 
     (21) 
     The heating element according to any one of (18) to (20), in which, in the connector, respective ones of the pair of expanded portions, the solder, and the pair of wiring lines are stacked in this order. 
     (22) 
     The heating element according to at least one of (18) to (21), in which the heat generator and the connector are provided on a flexible substrate. 
     (23) 
     The heating element according to any one of (18) to (22), in which the pair of wiring lines are covered with an insulating film, except for ends that are joined to the pair of expanded portions. 
     This application claims the benefit of Japanese Priority Patent Application No. 2019-114488 filed with the Japan Patent Office on Jun. 20, 2019, and Japanese Priority Patent Application No. 2019-200073 filed with the Japan Patent Office on Nov. 1, 2019, the entire contents of each which are incorporated herein by reference. 
     It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.