Electronic apparatus

An electronic apparatus includes: a chassis composed at least of an upper plate, a lower plate, and a side face; at least one plate-like antenna having a radio wave transmission/reception part which deals with radio waves in a millimeter wave band and forms one surface of the antenna; and a conductive reflection member having a main part with a reflection surface reflecting the radio waves in the millimeter wave band. The antenna is placed in an outer peripheral edge area including an outer peripheral edge of the upper plate in plan view in such a manner that the radio wave transmission/reception part faces the upper plate. The reflection member is so placed that the antenna is sandwiched between the reflection member and the side face in plan view. At least the side face transmits the radio waves. The reflection surface is directed toward the antenna.

FIELD OF THE INVENTION

The present invention relates to an electronic apparatus.

BACKGROUND OF THE INVENTION

An electronic apparatus such as a laptop personal computer (laptop PC) has an antenna for wireless communication (for example, see Japanese Unexamined Patent Application Publication No. 2013-162413).

SUMMARY OF THE INVENTION

In the electronic apparatus, the transmission/reception characteristics of the antenna may be inadequate depending on the antenna specifications. When the placement of the antenna is adjusted to improve the transmission/reception characteristics, the chassis structure may be limited. This may cause the degree of freedom of designing the electronic apparatus to be lowered.

It is an object of the present invention to provide an electronic apparatus having good antenna transmission/reception characteristics and a high degree of freedom in design.

One aspect of the present invention provides an electronic apparatus including: a chassis composed of at least an upper plate, a lower plate, and a side face; at least one plate-like antenna provided inside the chassis and having a radio wave transmission/reception part which deals with radio waves in a millimeter wave band and forms one surface of the antenna; and a conductive reflection member provided inside the chassis and having a main part with a reflection surface reflecting the radio waves in the millimeter wave band, wherein the antenna is placed in an outer peripheral edge area including an outer peripheral edge of the upper plate in plan view in such a manner that the radio wave transmission/reception part faces the upper plate, the reflection member is so placed that the antenna is sandwiched between the reflection member and the side face in plan view, at least the side face transmits the radio waves, and the reflection surface is directed toward the antenna.

It is preferred that the reflection member be in contact with at least either one of the upper plate and the lower plate in a heat transferable manner.

The reflection member may also have a support part which supports the antenna.

It is preferred that at least a partial region of the upper plate be a radio wave transmission part which transmits the radio waves, and the radio wave transmission part should overlap at least part of the radio wave transmission/reception part in plan view.

It is preferred that at least a partial area of the upper plate be a radio wave transmission part which allows the radio waves to be transmitted therethrough, and the radio wave transmission part should overlap at least part of the radio wave transmission/reception part in plan view.

It is preferred that the reflection member be made of a metal.

The electronic apparatus may further include a keyboard provided on the chassis, a display chassis coupled openably and closably to the chassis through a hinge, and a display mounted on the display chassis.

The one aspect of the present invention can provide an electronic apparatus having good antenna transmission/reception characteristics and a high degree of freedom in design.

DETAILED DESCRIPTION OF THE INVENTION

An electronic apparatus according to an embodiment will be described.FIG. 1is a perspective view of an electronic apparatus100according to a first embodiment.FIG. 2is a plan view of a second chassis102of the electronic apparatus100.FIG. 3is a perspective view illustrating the internal structure of the electronic apparatus100.FIG. 4is a partial sectional view along I-I inFIG. 2.FIG. 5is a perspective view illustrating the internal structure of the electronic apparatus100.FIG. 6is a sectional view illustrating the internal structure of the electronic apparatus100.FIG. 6is a partial sectional view along II-II inFIG. 2.

As illustrated inFIG. 1, the electronic apparatus100includes a first chassis101, a second chassis102(chassis), first to third antennas10,20,30, and a pair of reflection members40,40. The electronic apparatus100is, for example, a laptop PC (personal computer).

The first chassis101and the second chassis102are coupled along both edges through hinge mechanisms110. The first chassis101is rotatable around an axis of rotation formed by the hinge mechanisms110relative to the second chassis102.

The first chassis101is also called a display chassis. The second chassis102is also called a system chassis. The first chassis101and the second chassis102are each formed in the shape of a rectangular plate. Among the edges of the first chassis101and the second chassis102, the edges on which the hinge mechanisms110are provided are called a first base end section101band a second base end section102b, respectively. The edges opposite to the first base end section101band the second base end section102bare called a first open end section101aand a second open end section102a, respectively.

In the second chassis102, the direction from the second base end section102bto the second open end section102ais called “forward.” The direction opposite to the forward is called “rearward.” The forward and rearward directions are collectively referred to as a “longitudinal direction.” The left and right directions inFIG. 2are called “leftward” and “rightward,” respectively. The leftward and rightward directions are collectively referred to as a “lateral direction.”

As for the second chassis102, the positional relationships among respective components may be described by using an XYZ orthogonal coordinate system. The X direction is the longitudinal direction. The +X direction is the forward direction. The −X direction is the rearward direction. The Y direction is the lateral direction orthogonal to the X direction. The +Y direction is the rightward direction. The −Y direction is the leftward direction. The second base end section102bextends in the Y direction. The Z direction is the thickness direction of the second chassis102, which is a direction orthogonal to the X direction and the Y direction. The +Z direction is an upward direction. The −Z direction is a downward direction. The Z direction is a vertical direction, that is, a height direction. Viewing from the Z direction (the vertical direction) is called plan view.

The first chassis101is equipped with a display103. The display103is, for example, a liquid crystal display, an organic EL (Electro-Luminescence) display, or the like.

The second chassis102has an upper plate111(first main plate), a lower plate112(second main plate), a pair of side plates113,113, a front plate114, and a rear plate115. The second chassis102is a plate-like case body. The second chassis102is, for example, made of a metal such as an aluminum alloy or a magnesium alloy.

The upper plate111is formed along the XY plane. The upper plate111and the lower plate112face each other with a space. The upper plate111has a rectangular shape in plan view.

The lower plate112faces a mounting surface when the second chassis102is placed on the mounting surface (the upper surface of a desk or the lie). The lower plate112has a rectangular shape in plan view.

As illustrated inFIG. 3andFIG. 4, one side plate113(first side plate113A) in the pair of side plates113is formed from a left side edge111bof the upper plate111to a left side edge112bof the lower plate112. The outer surface of the first side plate113A is called a first side face113a(side face).

A first window113cis formed in the first side plate113A at a position corresponding to the first antenna10. The first window113cis formed in the thickness direction to penetrate the first side plate113A. The first window113chas a rectangular shape (for example, the shape of a non-square rectangle). The first window113cis formed to include a first main surface10aof the first antenna10as viewed from the lateral direction (Y direction).

As illustrated inFIG. 5andFIG. 6, the other side plate113(second side plate113B) in the pair of side plates113is formed from a right side edge111bof the upper plate111to a right side edge112bof the lower plate112. The outer surface of the second side plate113B is called a second side face113b(side face).

A second window113dis formed in the second side plate113B at a position corresponding to the second antenna20. The second window113dis formed in the thickness direction to penetrate the second side plate113B. The second window113dhas a rectangular shape (for example, the shape of a non-square rectangle). The second window113dis formed to include a second main surface20aof the second antenna20as viewed from the lateral direction (Y direction).

A radio wave transmission part118A (seeFIG. 4) is provided in the first window113c(seeFIG. 3). A radio wave transmission part118B (seeFIG. 6) is provided in the second window113d(seeFIG. 5). The radio wave transmission parts118A,118B each have a plate-like shape and allow radio waves to be transmitted therethrough. The radio wave transmission parts118A,118B close the windows113c,113d, respectively. Providing the radio wave transmission parts118A,118B can prevent foreign matter from entering the second chassis102through the windows113c,113d.

The radio wave transmission part118A is included in the first side plate113A. The outer surface of the radio wave transmission part118A is included in the first side face113a. At least part of the first side face113aallows radio waves to be transmitted therethrough. The radio wave transmission part118B is included in the second side plate113B. The outer surface of the radio wave transmission part118B is included in the second side face113b. At least part of the second side face113ballows radio waves to be transmitted therethrough. Note that the radio wave transmission parts118A,118B are not illustrated inFIG. 3andFIG. 5. The whole of the first side plate113A may be formed as the radio wave transmission part118A. Likewise, the whole of the second side plate113B may be formed as the radio wave transmission part118B.

The radio wave transmission parts118A,118B are made of a material to allow radio waves to be transmitted therethrough. As the material to allow radio waves to be transmitted therethrough, there is a resin, for example, a thermosetting resin such as an epoxy resin. It is preferred that the material to allow radio waves to be transmitted therethrough be a fiber reinforced resin obtained by impregnating the resin into fiber such as glass fiber or carbon fiber. The material to allow radio waves to be transmitted therethrough is, for example, an insulating material.

As illustrated inFIG. 1, the front plate114is formed from the front end of the upper plate111to the front end of the lower plate112. The rear plate115is formed from the rear end of the upper plate111to the rear end of the lower plate112.

The second chassis102is equipped with a keyboard107and a touch pad108. The keyboard107and the touch pad108are input devices.

As illustrated inFIG. 2, an area having a rectangular frame shape including an outer peripheral edge111dof the upper plate111in plan view is called an outer peripheral edge area117. The outer peripheral edge area117is composed of a front area117A, a pair of side areas117B,117B, and a rear area117C.

The front area117A is a linear strip area including a front edge111aof the upper plate111. The front area117A is an area over the entire length of the upper plate111in the lateral direction, that is, an area extending from one side edge111bof the upper plate111to the other side edge111bin the Y direction.

The side areas117B,117B are linear strip areas including the side edges111b,111bof the upper plate111, respectively. The side areas117B,117B are areas over the entire length of the upper plate111in the longitudinal direction, that is, areas extending from the front edge111ato a rear edge111cin the X direction. The side areas117B,117B extend rearward from both ends of the front area117A, respectively. For example, the width W1of the side area117B is equal to or smaller than the distance between a side edge107bof the keyboard107and the side edge111bopposite thereto.

The rear area117C is a linear strip area including the rear edge111cof the upper plate111. The rear area117C is formed over the entire length of the upper plate111in the lateral direction. The rear area117C extends from the rear end of one side area117B to the rear end of the other side area117B in the Y direction.

The outer peripheral edge area117is, for example, an area not including the keyboard107in plan view. The width of the front area117A, the width of each of the side areas117B,117B, and the width of the rear area117C are equal to one another.

Electronic components such as a circuit board, a central processing unit, a memory, and a battery are provided inside the second chassis102. Some of these electronic components are located inside the outer peripheral edge area117(seeFIG. 2) in plan view.

As illustrated inFIG. 3andFIG. 4, the first antenna10is an antenna for wireless communication.

As illustrated inFIG. 2, the first antenna10is provided inside the second chassis102at a position included in the outer peripheral edge area117in plan view. Specifically, the first antenna10is provided at a position included in the side area117B. Since the first antenna10is provided at the position included in the outer peripheral edge area117in plan view, the first antenna10is arranged close to the outer peripheral edge of the second chassis102. This makes it easy for radio waves from the outside to reach the first antenna10without being attenuated. This also makes it easy for radio waves radiated from the first antenna10to be radiated to the outside without being attenuated. Thus, the transmission/reception characteristics of the antenna10(at least either of the transmission and reception characteristics) can be enhanced.

As illustrated inFIG. 3andFIG. 4, the first antenna10is formed into a rectangular plate shape (for example, the shape of a non-square rectangular plate) as a whole. The first antenna10is so placed that the long side thereof faces in the longitudinal direction.

The first antenna10includes a body part11and a radio wave transmission/reception part12. The body part11includes a substrate having an RF circuit and the like. The body part11is formed into a rectangular plate shape (for example, the shape of a non-square rectangular plate).

The radio wave transmission/reception part12includes one or more antenna elements. The antenna elements can deal with radio waves in a millimeter wave band. In other words, the antenna elements can perform at least either the transmission or reception of radio waves in the millimeter wave band. For example, the radio waves in the millimeter wave band mean radio waves in a frequency band of 24 GHz to 100 GHz. The radio wave transmission/reception part12is provided on one face of the body part11having a plate shape, that is, on a first main surface11a(seeFIG. 4). Therefore, the radio wave transmission/reception part12constitutes at least part of one surface of the first antenna10(the first main surface10aas the upper surface inFIG. 4).

The first antenna10is so placed that the first main surface10afaces the upper plate111. Thus, the first antenna10is so placed that the radio wave transmission/reception part12faces the upper plate111. For example, the first antenna10becomes parallel (or substantially parallel) to the upper plate111. When the second chassis102is placed on a horizontal mounting surface, the upper plate111is positioned horizontally and the first antenna10is also positioned horizontally. Although it is desired that the first main surface10abe parallel to the upper plate111, the first main surface10amay be inclined, for example, at an angle of more than 0° and less than 45° with respect to the upper plate111.

A first reflection member40A as one reflection member40of the pair of reflection members40,40is formed into a rectangular plate shape (for example, the shape of a non-square rectangular plate). The whole of the first reflection member40A is a main part40Aa. The first reflection member40A is so placed that the long side thereof faces in the longitudinal direction.

An upper edge40aof the first reflection member40A reaches the upper plate111. A lower edge40bof the first reflection member40A reaches the lower plate112. The first reflection member40A is in contact with the upper plate111and the lower plate112on the upper edge40aand the lower edge40bin a heat transferable manner. Therefore, the heat of the first reflection member40A can be transferred to the upper plate111and the lower plate112. This can suppress a rise in temperature of the first reflection member40A.

The first reflection member40A may be fixed to at least one of the upper plate111and the lower plate112on the upper edge40aor the lower edge40b.

The first reflection member40A is formed in a direction to intersect the upper plate111, for example, along a plane perpendicular to the upper plate111(XZ plane).

The first reflection member40A is provided inside the second chassis102at a position more inward than the first antenna10(a position on the right side of the first antenna10). The first reflection member40A is positioned to face the first antenna10. One side (reflection surface40e) of the first reflection member40A is directed toward the first antenna10. It is preferred that the first reflection member40A be put in a position included in the side area117B (seeFIG. 2) in plan view.

Note that the attitude of the first reflection member40A is not limited to the attitude perpendicular to the upper plate111as long as the reflection surface40eis directed toward the first antenna10. For example, the first reflection member40A may be in such an attitude that the reflection surface40eis inclined at an angle of more than 45° and less than 90° with respect to the upper plate111. Thus, for example, the first reflection member40A is so placed that the reflection surface40eis inclined at an angle of more than 45° but not more than 90° with respect to the upper plate111.

The first reflection member40A may be provided away from the first antenna10or in contact with the first antenna10. In the embodiment, the first reflection member40A is placed away from the first antenna10.

The first reflection member40A is placed to cover the first main surface10aof the first antenna10as viewed from the lateral direction (Y direction). The upper edge40aof the first reflection member40A is in a position higher than the first main surface10a. The lower edge40bof the first reflection member40A is in a position lower than the first main surface10a. A front edge40cof the first reflection member40A is in a position more forward than the front edge of the first main surface10a. A rear edge40dof the first reflection member40A is in a position more rearward than the rear edge of the first main surface10a. Thus, the first reflection member40A is placed to include the first main surface10aas viewed from the lateral direction (Y direction).

Since the first reflection member40A is in the position to cover the first main surface10aof the first antenna10as viewed from the lateral direction (Y direction), it can be said that the first antenna10is sandwiched between the first reflection member40A and the first side face113a.

“The first antenna10is sandwiched between the first reflection member40A and the first side face113a” means that at least part of the first reflection member40A and at least part of the first side face113aare positioned to overlap each other with the first antenna10therebetween as viewed from the Y direction.

The reflection member40has conductivity. The reflection member40is such that at least the reflection surface40eis made of a conductive material. As the conductive material, a metal, a carbon material, or the like is used. Metals of which the reflection member40can be made include aluminum, copper, stainless steel, titanium, and alloys of them. When a metal is used as a constituent material of the reflection member40, the radio wave reflection characteristics of the reflection member40can be enhanced. The reflection member40may also be constructed to include a body made of a non-conductive material (resin, glass, or the like) and a metal layer formed on at least one surface (reflection surface) of the body.

Part of radio waves radiated from the side (from the left) to the electronic apparatus100enters the inside of the second chassis102through the first window113cof the first side plate113A, and is received by the radio wave transmission/reception part12of the first antenna10. Part of the radio waves passing through the first antenna10reaches the first reflection member40A, and is reflected on the reflection surface40e. The radio waves reflected on the reflection surface40eare headed to the left, and part of the radio waves is received by the radio wave transmission/reception part12of the first antenna10.

Part of radio waves radiated from the radio wave transmission/reception part12of the first antenna10is headed to the left, and radiated to the outside directly through the first window113c. The remaining radio waves are headed to the right and reflected on the reflection surface40eof the first reflection member40A. The radio waves reflected on the reflection surface40eare headed to the left and radiated to the outside through the first window113c.

As illustrated inFIG. 5andFIG. 6, the second antenna20is an antenna for wireless communication. The second antenna20has the same structure as that of the first antenna10(seeFIG. 3andFIG. 4).

As illustrated inFIG. 2, the second antenna20is provided inside the second chassis102at a position included in the outer peripheral edge area117in plan view. Specifically, the second antenna20is provided at a position included in the side area117B. Like the first antenna10, since the second antenna20is provided at the position included in the outer peripheral edge area117in plan view, the transmission/reception characteristics can be enhanced.

As illustrated inFIG. 5andFIG. 6, the radio wave transmission/reception part12of the second antenna20constitutes at least part of one surface of the second antenna20(the second main surface20aas the upper surface inFIG. 6).

The second antenna20is so placed that the second main surface20afaces the upper plate111. Thus, the second antenna20is so placed that the radio wave transmission/reception part12faces the upper plate111. For example, the second antenna20is positioned in parallel (substantially in parallel) to the upper plate111. When the second chassis102is placed on a horizontal mounting surface, the upper plate111is positioned horizontally and the second antenna20is also positioned horizontally. Although it is desired that the second main surface20abe parallel to the upper plate111, the second main surface20amay be inclined, for example, at an angle of more than 0° and less than 45° with respect to the upper plate111.

A second reflection member40B as the other reflection member40of the pair of reflection members40,40is formed into a rectangular plate shape (for example, the shape of a non-square rectangular plate). The whole of the second reflection member40B is a main part40Ba. The second reflection member40B has the same structure as the first reflection member40A.

An upper edge40aof the second reflection member40B reaches the upper plate111. A lower edge40bof the second reflection member40B reaches the lower plate112. The second reflection member40B is in contact with the upper plate111and the lower plate112on the upper edge40aand the lower edge40bin a heat transferable manner. The second reflection member40B may be fixed to at least one of the upper plate111and the lower plate112on the upper edge40aor the lower edge40b.

The second reflection member40B is formed in a direction to intersect the upper plate111, for example, along a plane (XZ plane) perpendicular to the upper plate111.

The second reflection member40B is provided inside the second chassis102at a position more inward than the second antenna20(a position on the left side of the second antenna20). The second reflection member40B is positioned to face the second antenna20. One side (reflection surface40e) of the second reflection member40B is directed toward the second antenna20. It is preferred that the second reflection member40B be put in a position included in the side area117B (seeFIG. 2) in plan view.

Note that the attitude of the second reflection member40B is not limited to the attitude perpendicular to the upper plate111as long as the reflection surface40eis directed toward the second antenna20. For example, the second reflection member40B may be in such an attitude that the reflection surface40eis inclined at an angle of more than 45° and less than 90° with respect to the upper plate111. Thus, for example, the second reflection member40B is so placed that the reflection surface40eis inclined at an angle of more than 45° but not more than 90° with respect to the upper plate111.

The second reflection member40B may be provided away from the second antenna20or in contact with the second antenna20. In the embodiment, the second reflection member40B is placed away from the second antenna20.

The second reflection member40B is placed to cover the second main surface20aof the second antenna20as viewed from the lateral direction (Y direction). The upper edge40aof the second reflection member40B is in a position higher than the second main surface20a. The lower edge40bof the second reflection member40B is in a position lower than the second main surface20a. A front edge40cof the second reflection member40B is in a position more forward than the front edge of the second main surface20a. A rear edge40dof the second reflection member40B is in a position more rearward than the rear edge of the second main surface20a. Thus, the second reflection member40B is placed to include the second main surface20aas viewed from the lateral direction (Y direction).

Since the second reflection member40B is in the position to cover the second main surface20aof the second antenna20as viewed from the lateral direction (Y direction), it can be said that the second antenna20is sandwiched between the second reflection member40B and the second side face113b.

“The second antenna20is sandwiched between the second reflection member40B and the second side face113b” means that at least part of the second reflection member40B and at least part of the second side face113bare positioned to overlap each other with the second antenna20therebetween as viewed from the Y direction.

Part of radio waves radiated from the side (from the right) to the electronic apparatus100enters the inside of the second chassis102through the second window113dof the second side plate113B, and is received by the radio wave transmission/reception part12of the second antenna20. Part of the radio waves passing through the second antenna20reaches the second reflection member40B, and is reflected on the reflection surface40e. The radio waves reflected on the reflection surface40eare headed to the right, and part of the radio waves is received by the radio wave transmission/reception part12of the second antenna20.

Part of radio waves radiated from the radio wave transmission/reception part12of the second antenna20is headed to the right, and radiated to the outside directly through the second window113d. The remaining radio waves are headed to the left and reflected on the reflection surface40eof the second reflection member40B. The radio waves reflected on the reflection surface40eare headed to the right and radiated to the outside through the second window113d.

As illustrated inFIG. 1andFIG. 2, the third antenna30is an antenna for wireless communication. The third antenna30has the same structure as that of the first antenna10(seeFIG. 3andFIG. 4). As illustrated inFIG. 2, the third antenna30is provided inside the second chassis102at a position included in the front area117A in plan view.

The radio wave transmission/reception part12of the third antenna30constitutes at least part of one side (a third main surface30a) of the third antenna30.

The third antenna30is so placed that the third main surface30afaces the upper plate111. An area of the upper plate111to face the third antenna30is formed as a radio wave transmission part (not illustrated) to allow radio waves to be transmitted therethrough. The radio wave transmission part is made of a material to allow radio waves to be transmitted therethrough such as a synthetic resin.

Part of radio waves radiated from above to the electronic apparatus100is received by the third antenna30through the radio wave transmission part. Part of radio waves radiated by the third antenna30is radiated to the outside through the radio wave transmission part.

According to the electronic apparatus100of the embodiment, the first reflection member40A is so placed that the first antenna10is arranged between the first reflection member40A and the side face113ain plan view. The second reflection member40B is so placed that the second antenna20is arranged between the second reflection member40B and the side face113bin plan view. The reflection members40A,40B are so placed that the reflection surfaces40e,40eare directed toward the antennas10,20, respectively. Therefore, even when part of radio waves entering the second chassis102from the sides once passes through the antennas10,20, it is reflected back on the reflection members40and received by the antennas10,20, respectively. Although part of radio waves radiated from each of the antennas10,20is headed to the inside of the second chassis102, this radio wave is reflected on the reflection member40, directed toward the outside, and radiated to the outside. Thus, the transmission/reception characteristics (for example, the directivity) of the antennas10,20can be enhanced.

In the electronic apparatus100, since each of the antennas10,20is so placed that the radio wave transmission/reception part12faces the upper plate111, the degree of freedom in design related to the attitude and mounting position of the antenna10,20, and the like can be increased. For example, since the antenna10,20can be positioned along the upper plate111, the antenna10,20can be placed in a portion in which the height of the interior space of the second chassis102is small. This can make the second chassis102thinner.

FIG. 7is a diagram illustrating an example of a radiation pattern of radio waves of the antenna10in the electronic apparatus100. As illustrated inFIG. 7, in the electronic apparatus100, the directivity of the first antenna10to the side (to the left inFIG. 7, that is, in the −Y direction) is high.

To clarify the effect of the electronic apparatus100, an electronic apparatus as a comparative form will be illustrated.

FIG. 8is a sectional view illustrating the internal structure of an electronic apparatus200according to a first comparative form. As illustrated inFIG. 8, in the electronic apparatus200, an antenna210is so placed vertically that the radio wave transmission/reception part12faces outward. No reflection member is provided in this form.

FIG. 9is a diagram illustrating an example of a radiation pattern of radio waves of the antenna210in the electronic apparatus200. As illustrated inFIG. 9, the antenna210has a high directivity toward one side. However, the antenna210is placed vertically, the electronic apparatus200is inferior in terms of the degree of freedom in design.

FIG. 10is a sectional view illustrating the internal structure of an electronic apparatus300according to a second comparative form. As illustrated inFIG. 10, the electronic apparatus300has the same structure as the electronic apparatus100illustrated inFIG. 4except that no reflection member is provided.

FIG. 11is a diagram illustrating an example of a radiation pattern of radio waves of an antenna310in the electronic apparatus300. As illustrated inFIG. 11, the antenna310of the electronic apparatus300has a low directivity.

By comparingFIG. 7,FIG. 9, andFIG. 11, it is found that the electronic apparatus100of the embodiment illustrated inFIG. 7has a high antenna directivity and can enhance the degree of freedom in design.

Since the reflection members40are provided in the electronic apparatus100, the electromagnetic effects of electronic components (the central processing unit and the like) mounted in the second chassis102on the antennas10,20can be suppressed. This can lead to reducing noise in the antennas10,20and hence increase the transmission/reception characteristics.

Since the reflection members40are provided in the electronic apparatus100, the electromagnetic effects between the first antenna10and the second antenna20can also be suppressed. Further, since the reflection members are provided in the electronic apparatus100, the electromagnetic effects of any other electronic apparatus on the electronic components inside the second chassis102can be suppressed.

FIG. 12is a sectional view illustrating the internal structure of an electronic apparatus400according to a first example of a second embodiment. Components common to the electronic apparatus of the other embodiment are given the same reference numerals to omit the description thereof.

In the electronic apparatus400, at least part of an upper plate411of a second chassis402constitutes a radio wave transmission part120. The radio wave transmission part120is formed in an area including a side edge411bof the upper plate411. The radio wave transmission part120is made, for example, of a material to allow radio waves to be transmitted therethrough (as described above). The radio wave transmission part120includes the whole of the radio wave transmission/reception part12of the antenna10in plan view.

The second chassis402is made of a conductive material such a metal.

At least part of a side plate413of the second chassis402constitutes a radio wave transmission part121. The radio wave transmission part121is formed in a position corresponding to the antenna10. The radio wave transmission part121is made of a material to allow radio waves to be transmitted therethrough such as a synthetic resin.

The radio wave transmission/reception part12of the antenna10is arranged to face the radio wave transmission part120.

A reflection member440has a main part440aand a shielding part440b. Like the main part40Aa illustrated inFIG. 4, the main part440ais formed into a rectangular plate shape. The main part440ais formed in a direction to intersect the upper plate411, for example, along a plane (XZ plane) perpendicular to the upper plate411.

The shielding part440bis formed into a plate shape (for example, a rectangular plate shape). The shielding part440bextends from the upper edge of the main part440atoward a side plate413between the antenna10and the radio wave transmission part120. For example, the shielding part440bis parallel to the upper plate411.

The shielding part440boverlaps at least part of the radio wave transmission/reception part12of the antenna10in plan view. In this example, the shielding part440bincludes almost the whole of the radio wave transmission/reception part12of the antenna10in plan view. A tip440b1of the shielding part440bis located in a position more leftward than an outer edge12aof the radio wave transmission/reception part12.

The reflection member440has conductivity. The reflection member440is made of a conductive material such as a metal (as described above).

FIG. 13is a diagram illustrating an example of a radiation pattern of radio waves of the antenna10in the electronic apparatus400. As illustrated inFIG. 13, the antenna10of the electronic apparatus400has a directivity schematically to one side (−Y direction).

FIG. 14is a sectional view illustrating the internal structure of an electronic apparatus500according to a second example of the second embodiment.

In the electronic apparatus500, a reflection member540has the main part440aand a shielding part540b. The shielding part540bhas an extension length from the main part440a, which is shorter than that of the shielding part440bin the first example (seeFIG. 12). The shielding part540boverlaps part of the radio wave transmission/reception part12of the antenna10in plan view. A tip540b1of the shielding part540bis located in a position more rightward than the outer edge12aof the radio wave transmission/reception part12and more leftward than an inner edge12bthereof.

FIG. 15is a diagram illustrating an example of a radiation pattern of radio waves of the antenna10in the electronic apparatus500. As illustrated inFIG. 15, the antenna10of the electronic apparatus500has a diagonally upward directivity.

FIG. 16is a sectional view illustrating the internal structure of an electronic apparatus600according to a third example of the second embodiment.

In the electronic apparatus600, a reflection member640has the main part440aand a shielding part640b.

The shielding part640bhas an extension length from the main part440a, which is shorter than that of the shielding part540bin the second example (seeFIG. 14). The shielding part640boverlaps part of the radio wave transmission/reception part12of the antenna10in plan view. A tip640b1of the shielding part640bis located in a position more rightward than the outer edge12aof the radio wave transmission/reception part12and more leftward than the inner edge12bthereof.

FIG. 17is a diagram illustrating an example of a radiation pattern of radio waves of the antenna10in the electronic apparatus600. As illustrated inFIG. 17, the antenna10has a diagonally upward directivity in the electronic apparatus600. The direction of the directivity in the electronic apparatus600is larger in inclination angle with respect to the Y direction than the direction of the directivity in the electronic apparatus500illustrated inFIG. 15.

FIG. 18is a sectional view illustrating the internal structure of an electronic apparatus700according to a fourth example of the second embodiment.

In the electronic apparatus700, a reflection member740is composed only of the main part440a. Since there is no shielding part, the reflection member740does not overlap any part of the radio wave transmission/reception part12of the antenna10in plan view.

FIG. 19is a diagram illustrating an example of a radiation pattern of radio waves of the antenna10in the electronic apparatus700. As illustrated inFIG. 19, the antenna10has a diagonally upward directivity in the electronic apparatus700. The direction of the directivity in the electronic apparatus700is larger in inclination angle with respect to the Y direction than the direction of the directivity in the electronic apparatus600illustrated inFIG. 17.

As illustrated inFIG. 13,FIG. 15,FIG. 17, andFIG. 19, the directivity of the antenna10varies according to the length of the shielding part. Therefore, the directivity of the antenna10can be adjusted easily according to the purpose of use.

In the electronic apparatuses400,500,600, and700illustrated inFIG. 12,FIG. 14,FIG. 16, andFIG. 18, the transmission/reception characteristics (for example, the directivity) of the antennas10,20can be increased. In the electronic apparatuses400,500,600, and700, the degree of freedom in design can also be enhanced.

Although the radio wave transmission part120illustrated inFIG. 12,FIG. 14,FIG. 16, andFIG. 18includes the whole of the radio wave transmission/reception part12of the antenna10in plan view, the radio wave transmission part may be constructed to overlap only part of the radio wave transmission/reception part of the antenna in plan view.

For example, when an inner edge120aof the radio wave transmission part120illustrated inFIG. 18is located in a position more outward (more in the −Y direction) than the inner edge12bof the radio wave transmission/reception part12of the antenna10, the upper plate411overlaps part of the radio wave transmission/reception part12in plan view. Depending on the position of the inner edge120aof the radio wave transmission part120in the Y direction, the area of the radio wave transmission/reception part12to be covered with the upper plate411is increased or decreased.

FIG. 20,FIG. 22,FIG. 24, andFIG. 26are sectional views illustrating internal structures of electronic apparatuses according to fifth to eighth examples of the second embodiment, respectively.FIG. 21,FIG. 23,FIG. 25, andFIG. 27are diagrams illustrating examples of radiation patterns of radio waves of the antenna10in the fifth to eighth examples of the second embodiment, respectively.

InFIG. 20, since the inner edge120aof the radio wave transmission part120is located in a position more outward (more in the −Y direction) than the outer edge12aof the radio wave transmission/reception part1, the upper plate411overlaps the whole of the radio wave transmission/reception part12in plan view. In this case, as illustrated inFIG. 21, the antenna10exhibits a directivity schematically to one side (−Y direction).

InFIG. 22, the inner edge120aof the radio wave transmission part120is located more outward (more in the −Y direction) than the inner edge12bof the radio wave transmission/reception part12and more inward (more in the +Y direction) than the outer edge12aof the radio wave transmission/reception part12. The upper plate411overlaps about half area of the radio wave transmission/reception part12in plan view. In this case, as illustrated inFIG. 23, the antenna10has a diagonally upward directivity.

InFIG. 24, since the position of the inner edge120aof the radio wave transmission part120in the Y direction is closer to the position of the inner edge12bof the radio wave transmission/reception part12in the Y direction, the overlapped area of the radio wave transmission/reception part12with the upper plate411in plan view is very little. In this case, as illustrated inFIG. 25, a directivity with a large inclination angle with respect to the Y direction can be obtained.

InFIG. 26, since the position of the inner edge120aof the radio wave transmission part120in the Y direction is more inward (more in the +Y direction) than the position of the inner edge12bof the radio wave transmission/reception part12in the Y direction, the upper plate411does not overlap the radio wave transmission/reception part12in plan view. In this case, as illustrated inFIG. 27, a directivity with a larger inclination angle with respect to the Y direction can be obtained.

The directivity of the antenna10varies according to the relative position of the radio wave transmission/reception part12and the upper plate411. Therefore, the directivity of the antenna10can be adjusted easily.

FIG. 28is a sectional view illustrating the internal structure of a variation of the electronic apparatus100according to the first embodiment. Components common to the electronic apparatus of the other embodiment are given the same reference numerals to omit the description thereof.

As illustrated inFIG. 28, an electronic apparatus800is different from the electronic apparatus100illustrated inFIG. 4in that a support plate41(support part) is formed on the outer surface (reflection surface40e) of the reflection member40to support the antenna10. The support plate41is parallel to the upper plate111, and extends outwardly from the outer surface (reflection surface40e) of the reflection member40. The support plate41is made, for example, of a metal. The support plate41can support the antenna10in a predetermined height position between the upper plate111and the lower plate112.

Since the support plate41has holes41athrough which legs13provided on the lower surface of the body part11of the antenna10are inserted, the support plate41is in contact with the lower surface of the body part11of the antenna10. Therefore, the contact area between the support plate41and the body part11is large, and hence the heat of the body part11is efficiently transferred to the support plate41.

The electronic apparatus800can transfer the heat of the reflection member40to the upper plate111and the lower plate112through the support plate41. This can suppress the temperature rise of the reflection member40. Since the electronic apparatus800has the support plate41, the structure of supporting the antenna10can be simplified.

FIG. 29is a perspective view of an electronic apparatus900according to a third embodiment.

As illustrated inFIG. 29, the electronic apparatus900includes a chassis902, first to third antennas10,20,930, and reflection members40,40. The chassis902has a flat plate-like case body. A display903is mounted on the chassis902. The electronic apparatus900is, for example, a smartphone, a tablet terminal, or the like.

The chassis902has an upper plate911, a lower plate912, and a pair of side plates913,913(913A,913B).

An outer peripheral edge area917is an area including an outer peripheral edge of the upper plate911of the chassis902, which is a rectangular frame-like area surrounding the display903in plan view. The outer peripheral edge area917has a front area917A including the front edge of the upper plate911, side areas917B,917B including side edges, and a rear area917C including the rear edge.

The antenna10is formed in one side area917B in plan view. The antenna20is formed in the other side area917B in plan view. The antenna930is formed in the rear area917C in plan view. The antennas10,20,930are so placed in the chassis902that the respective radio wave transmission/reception parts12face the upper plate911of the chassis902. Note that the antenna930may be formed in the front area917A.

A first reflection member40A of the reflection members40,40is so placed that the antenna10is sandwiched between the first reflection member40A and a side face913aof one side plate913(913A) of the chassis902. A second reflection member40B is so placed that the antenna20is sandwiched between the second reflection member40B and a side plate913(913B) of the other side face913bof the chassis902.

Since the reflection members40,40are included in the electronic apparatus900, the transmission/reception characteristics (for example, the directivity) of the antennas10,20can be increased. In the electronic apparatus900, the degree of freedom in design can also be increased.

The specific structures of this invention are not limited to those in the above-described embodiments, and any design change can be made without departing from the gist of this invention. The respective structures described in the aforementioned embodiments can be combined arbitrarily.

For example, as illustrated inFIG. 4, the reflection member40is in contact with both the upper plate111and the lower plate112in the electronic apparatus100, but the reflection member may be in contact with only either one of the upper plate and the lower plate. Further, the reflection member may be held in the chassis by an unillustrated support structure.

As illustrated inFIG. 2, the third antenna30is provided in the electronic apparatus100at a position included in the front area117A of the outer peripheral edge area117in plan view, but the third antenna may be provided at a position included in the rear area of the outer peripheral edge area in plan view.

Further, the electronic apparatus100includes the first to third antennas10,20,30, but the third antenna may not be required.

The electronic apparatus100includes the antennas10,20arranged respectively between the reflection members40and the side faces of the second chassis102, but the number of antennas arranged between the reflection members and the side faces of the chassis is not limited to two. The number of antennas may be one, or any number of more than two.

Further, the radio waves in the millimeter wave band may be in a frequency band from 24 GHz to 300 GHz.