JP7013975B2 - Movable cooling device, image generator, image projection device - Google Patents

Description

The present invention relates to a movable cooling device, an image generation device, and an image projection device.

In an image projection device such as a projector, a method of using a DMD element as an image display element is known. In such an image projection device, there is known a method of increasing the resolution of a projected image by shifting the DMD element by half a pixel in a fine cycle by, for example, a drive actuator using a coil and a permanent magnet.
However, in such a high resolution method, there is a problem that heat generated by the coil is transmitted to the DMD element and the temperature of the DMD element is raised.
In order to solve such a problem, various cooling methods are known, for example, a refrigerant is circulated through the coil for cooling the coil (see, for example, Patent Document 1 and the like). However, in the configuration as described in Patent Document 1, there is a problem that the coil is arranged on the fixed side and it is difficult to separately provide the cooling means on the movable portion side.

The present invention has been made based on the above problems, and an object of the present invention is to provide a movable cooling device that efficiently cools a coil arranged in a movable portion.

The movable cooling device according to the present invention is configured to include a movable plate and a substrate on which fins are arranged, and a heat sink connected to the movable plate and one of which are arranged between the movable plate and the heat sink. Two fixing plates that movably hold the movable plate between the one and the other, a magnet arranged on the fixing plate on the heat sink side of the two fixing plates, and a magnet formed on the heat sink. An opening penetrating the substrate, a coil having an air core arranged in the opening and facing the magnet, and a surface opposite to the surface of the substrate on which the magnet and the coil face each other. A fin arranged on a surface and a blower for sending air toward the fins are provided, and the fins are extended in a direction along the air sent by the blower to form a flow path for the air. The fins are not provided in the range connecting the blower and the air core of the coil in the flow path, and the distance between the coil and the magnet is larger than the distance between the adjacent fins. It is a feature .

According to the movable cooling device of the present invention, the coil arranged in the movable portion can be efficiently cooled.

It is a figure which shows an example of the image projection apparatus as an embodiment of this invention. It is a figure which shows an example of the functional structure of the image projection apparatus of this invention. It is a figure which shows an example of the optical engine of the image projection apparatus shown in FIG. It is a figure which shows an example of the illumination optical unit shown in FIG. It is a figure which shows an example of the structure of the projection optical system unit 60. It is a figure which shows an example of the image display unit as an embodiment of this invention. It is a figure which shows the assembly example of the image display unit shown in FIG. It is a perspective view which shows typically the structure of the position detection part shown in FIG. 7. It is sectional drawing which shows typically the structure of the position detection part shown in FIG. It is a perspective view which shows typically the structure of the driving force generation part shown in FIG. 7. It is a perspective view which shows typically the structure of the movable unit of this invention. It is a perspective view which shows typically the structure of the fixed unit of this invention. It is a perspective view which shows typically the structure of the movable cooling device of this invention. It is a figure which shows the arrangement example of the fin of a heat sink.

(Configuration of image projection device)
FIG. 1 is a diagram illustrating the projector 100 according to the embodiment of the present invention.

The projector 100 is an example of an image projection device, has an emission window 103, an external I / F9, and is provided with an optical engine for generating a projected image inside. When image data is transmitted from, for example, a personal computer or a digital camera connected to an external I / F9, the projector 100 generates a projected image based on the transmitted image data by an optical engine, as shown in FIG. An image is projected from the exit window 103 onto the screen S.

In the drawings shown below, the X direction is the width direction of the projector 100, the Y direction is the depth direction of the projector 100, and the Z1Z2 direction is the height direction of the projector 100. Further, in the following, the projector 100 may be described with the emission window 103 side as the upper side and the side opposite to the emission window 103 as the lower side.

FIG. 2 is a block diagram illustrating the functional configuration of the projector 100 in the embodiment.

As shown in FIG. 2, the projector 100 includes a power supply 104, a main switch SW105, an operation unit 7, an external I / F9, a system control unit 90, a fan 20, and an optical engine 115.

The power supply 104 is connected to a commercial power supply, converts voltage and frequency for the internal circuit of the projector 100, and supplies power to the system control unit 90, the fan 20, the optical engine 115, and the like.

The main switch SW105 is used for the ON / OFF operation of the projector 100 by the user. When the main switch SW105 is operated to ON while the power supply 104 is connected to a commercial power source via a power cord or the like, the power supply 104 starts supplying power to each part of the projector 100, and the main switch SW105 is operated to OFF. Then, the power supply 104 stops the power supply to each part of the projector 100.

The operation unit 7 is a button or the like that receives various operations by the user, and is provided on the upper surface of the projector 100, for example. The operation unit 7 accepts operations by the user, such as the size, color tone, and focus adjustment of the projected image. The user operation received by the operation unit 7 is sent to the system control unit 90.

The external I / F 9 has a connection terminal connected to, for example, a personal computer, a digital camera, or the like, and outputs image data transmitted from the connected device to the system control unit 90.

The system control unit 90 includes an image control unit 91 and a movement control unit 92. The system control unit 90 includes, for example, a CPU, ROM, RAM, and the like, and the CPU cooperates with the RAM to execute a program stored in the ROM, thereby realizing the functions of each unit.

The image control unit 91 is an example of the image control means, and is a digital micromirror device DMD (Digital Micromirror Device) provided in the image display unit 1 of the optical engine 115 based on the image data input from the external I / F9. Hereinafter, simply "DMD")) 2 is controlled to generate an image to be projected on the screen S.

The movement control unit 92 is an example of the movement control means, and moves the movable unit 5 movably provided in the image display unit 1 to control the position of the DMD 2 provided in the movable unit 5.

The fan 20 is controlled by the system control unit 90 to rotate, and cools the light source 30 of the optical engine 115.

The optical engine 115 has a light source 30, an illumination optical system unit 40, an image display unit 1, and a projection optical system unit 60, and is controlled by the system control unit 90 to project an image on the screen S.

The light source 30 is, for example, a mercury high-pressure lamp, a xenon lamp, an LED, or the like, and is controlled by the system control unit 90 to irradiate the illumination optical system unit 40 with light.

The illumination optical system unit 40 has, for example, a color wheel, a light tunnel, a relay lens, and the like, and guides the light emitted from the light source 30 to the DMD 2 provided in the image display unit 1.

The image display unit 1 has a fixed unit 6 that is fixedly supported and a movable unit 5 that is movably provided with respect to the fixed unit 6. The movable unit 5 has a DMD2, and the position of the system control unit 90 with respect to the fixed unit 6 is controlled by the movement control unit 92. The DMD 2 is an example of an image generation means, which is controlled by the image control unit 91 of the system control unit 90 and modulates the light guided by the illumination optical system unit 40 to generate a projection image.

The projection optical system unit 60 has, for example, a plurality of projection lenses, mirrors, and the like, and magnifies an image generated by DMD 2 of the image display unit 1 and projects it on the screen S.

(Optical engine configuration)
Next, the configuration of each part of the optical engine 115 of the projector 100 will be described.

FIG. 3 is a perspective view illustrating the optical engine 115 in the embodiment. As shown in FIG. 3, the optical engine 115 has a light source 30, an illumination optical system unit 40, an image display unit 1, and a projection optical system unit 60, and is provided inside the projector 100.

The light source 30 is provided on the side surface of the illumination optical system unit 40 and irradiates light in the X direction. The illumination optical system unit 40 guides the light emitted from the light source 30 to the image display unit 1 provided at the lower part. The image display unit 1 generates a projected image using the light guided by the illumination optical system unit 40. The projection optical system unit 60 is provided on the upper part of the illumination optical system unit 40, and projects the projected image generated by the image display unit 1 to the outside of the projector 100.

The optical engine 115 according to the present embodiment is configured to project an image upward using the light emitted from the light source 30, but the optical engine 115 may be configured to project an image in the horizontal direction. good.

(Illumination optical system unit)
FIG. 4 is a diagram illustrating the illumination optical system unit 40 in the embodiment.

As shown in FIG. 4, the illumination optical system unit 40 has a color wheel 401, a light tunnel 402, relay lenses 403 and 404, a cylinder mirror 405, and a concave mirror 406.

The color wheel 401 is, for example, a disk in which filters of each color of R (red), G (green), and B (blue) are provided in different portions in the circumferential direction. The color wheel 401 rotates at high speed to time-divide the light emitted from the light source 30 into RGB colors.

The light tunnel 402 is formed in a square cylinder shape by, for example, laminating flat glass or the like. The light tunnel 402 multi-reflects the light of each RGB color transmitted through the color wheel 401 on the inner surface to make the luminance distribution uniform and guide it to the relay lenses 403 and 404.

The relay lenses 403 and 404 collect light while correcting the axial chromatic aberration of the light emitted from the light tunnel 402.

The cylinder mirror 405 and the concave mirror 406 reflect the light emitted from the relay lenses 403 and 404 to the DMD 2 provided in the image display unit 1. The DMD2 modulates the reflected light from the concave mirror 406 to generate a projected image.

(Projection optical system unit)
FIG. 5 is a diagram illustrating the internal configuration of the projection optical system unit 60 in the embodiment.

As shown in FIG. 5, the projection optical system unit 60 is provided with a projection lens 601, a folded mirror 602, and a curved mirror 603 inside the case.

The projection lens 601 has a plurality of lenses, and the projection image generated by the DMD 2 of the image display unit 1 is imaged on the folded mirror 602. The folded mirror 602 and the curved mirror 603 reflect the imaged projected image so as to magnify it, and project it onto a screen S or the like outside the projector 100.

(Image display unit)
FIG. 6 is a perspective view illustrating the image display unit 1 as the high resolution module in the embodiment. Further, FIG. 7 is a side view illustrating the image display unit 1 in the embodiment.

As shown in FIGS. 6 and 7, the image display unit 1 functionally includes a position detection unit 3 mainly including the DMD 2 and arranged above, and a driving force generation unit 4 including a heat sink 14. Have.
As shown in an exploded view in FIG. 8, the position detection unit 3 corresponds to the upper layer side and the second floor portion of the image display unit 1, and is a position detection FPC on which a DMD substrate 13 having a DMD 2 and a Hall element 15 are mounted. It has (Flexible Printed Circuits) 18 and a position detection magnet 32.
The position detection unit 3 also has a top plate 21 as a first fixing plate, a base plate 25 as a second fixing plate, a movable plate 11, and a support plate 22 as a third fixing plate.
A strut 26 is arranged between the first fixing plate and the third fixing plate, that is, between the top plate 21 and the support plate 22, and the strut 26 maintains the distance between the two plates at a predetermined distance. Has been done.
Further, the movable plate 11 is arranged between the support plate 22 and the top plate 21, and the balls 24 are located between the movable plate 11 and the top plate 21 and between the movable plate 11 and the support plate 22, respectively. Is provided to form the ball support portion 28.
The movable plate 11 is configured to reduce friction during movement by being sandwiched by the balls 24 from two directions, upper and lower, at a total of three points.

The DMD 2 is provided on the surface of the movable plate 11 side, and is movably provided together with the movable plate 552 and the coupling plate 553. The DMD2 has an image generation surface in which a plurality of movable micromirrors are arranged in a grid pattern. Each of the DMD2 micromirrors is provided with a mirror surface that can be tilted around a twist axis, and is driven ON / OFF based on an image signal transmitted from an image control unit 91 of the system control unit 90.

When the micromirror is "ON", for example, the tilt angle is controlled so as to reflect the light from the light source 30 on the projection optical system unit 60. Further, in the case of "OFF", for example, the tilt angle of the micromirror is controlled in the direction in which the light from the light source 30 is reflected toward the OFF light plate (not shown).

In this way, the DMD 2 controls the tilt angle of each micromirror by the image signal transmitted from the image control unit 91, and modulates the light emitted from the light source 30 and passed through the illumination optical system unit 40 to produce a projected image. Generate.

The base plate 25, which is the second fixing plate, is fixed to the top plate 21 so as to be integrated with the top plate 21 at a predetermined interval, has a dustproof function when the movable plate 11 operates, and regulates the position of the ball 24. ..
The clearance between the movable plate 11 and the ball 24 can be adjusted by the amount of pushing of the adjusting screw 27.

The position detection magnet 32 is a permanent magnet attached to the movable portion 11 side of the base plate 25.
One end of the position detection FPC 18 is attached to the DMD substrate 13, and the other end is attached to any of the fixing units 6 described later, for example, the base plate 25.
The position detection FPC 18 has flexibility so that translation and rotation operations can be performed in a plane without hindering the movement of the movable plate 11, and even if one end is pulled, the amount of movement thereof. It has multiple creases to absorb.
The Hall element 15 is mounted on the position detection FPC, and is a position calculation means that detects a change in the magnetic flux density caused by the position detection magnet 32 and calculates a position from the change in the magnetic flux density.
That is, when the position detection FPC 18 moves due to the movement of the movable plate 11, the Hall element 15 can detect the change in the magnetic flux density and calculate the position of the movable plate 11.

As shown in FIG. 9, the driving force generating unit 4 has a driving magnet 23 attached to the fourth fixing plate 29, a driving FPC 16, a heat sink 14, and a coil 12.

The drive magnet 23 is a permanent magnet attached to the fourth fixing plate 29 so as to face the coil 12.

One end of the drive FPC 16 is attached to the coil 12, and the other end is attached to the fourth fixing plate 29.
Like the position detection FPC 18, the drive FPC 16 has flexibility so that translation and rotation operations can be performed in a plane without hindering the movement of the coil 12, and one end thereof is pulled. It has multiple creases to absorb the amount of movement, if any.

The heat sink 14 is an example of heat dissipation means, and at least a part thereof is provided so as to abut on the DMD 2 or the DMD substrate 13. With such a configuration, the heat sink 14 suppresses the temperature rise of the DMD 2 in the image display unit 1 according to the present embodiment, and the occurrence of malfunctions and failures due to the temperature rise of the DMD 2 is reduced. There is.

The heat sink 14 has a base portion 140 which is a plate-shaped base material portion, a surface opposite to the driving magnet 23, and fins 141 formed upright from the base portion 140 toward the lower side in the present embodiment. Have.
The heat sink 14 also has a support column 142 that is fastened to the movable plate 11 by screws.
A plurality of openings 143 are formed in the base 140 so as to penetrate the base 140 at positions corresponding to the driving magnets 23, and a coil 12 is attached so as to fit into the openings 143.
The "corresponding position" here is a position facing the driving magnet 23 when the movable plate 11 is in the initial position. However, as will be described later, since the movable plate 11 operates by the electromagnetic force between the driving magnet 23 and the coil 12, the positions do not always match correctly when viewed from above.

The coil 12 is an air-core coil attached to the base 140 of the heat sink 14. The coil 12 is formed by winding an electric wire around an axis parallel to the Z1Z2 direction.
The coil 12 is fixed to the opening 143 of the base 140, and is held so that a current can be applied via the driving FPC 16.
The coil 12 also has coils 12a and 12b arranged so as to generate Lorentz force in the X direction, and coils 12c arranged so as to generate Lorentz force in the Y direction. The movable plate 11 freely moves in the X direction or the Y direction due to the Lorentz force generated in the coils 12a, 12b, 12c and the driving magnet 23.

The movable plate 11 moves in the Y direction or the −Y direction due to the Lorentz force generated in the coil 12a and the driving magnet 23, and the coil 12b and the driving magnet 23. Further, the movable plate 11 is displaced so as to rotate in the XY plane due to the Lorentz force generated in the opposite directions of the coil 12a and the driving magnet 23 and the coil 12b and the driving magnet 23.

For example, when a current is passed so that a Lorentz force in the Y direction is generated in the coil 12a and the driving magnet 23 and a Lorentz force in the −Y direction is generated in the coil 12b and the driving magnet 23, the movable plate 11 has an upper surface. It is displaced so that it rotates clockwise in the visual direction. Further, when a current is passed so that the Lorentz force in the −Y direction is generated in the coil 12a and the driving magnet 23 and the Lorentz force in the + Y direction is generated in the coil 12b and the driving magnet 23, the movable plate 11 is subjected to the upper surface. It is displaced so as to rotate counterclockwise visually.

The operation of the image display unit 1 will be described with reference to an immovable fixed unit 6 fixed to the housing and a movable unit 5 operating with respect to the fixed unit 6.
Since the movable unit 5 and the fixed unit 6 are each a group of the components of the image display unit 1 as described above according to the mode of operation, they are individually numbered with the same number. The description of the element will be omitted as appropriate.

As shown in FIG. 9, the movable unit 5 includes a DMD 2, a DMD substrate 13, a movable plate 11, a coil 12, a heat sink 14, a position detection FPC 18, a drive FPC 16, and a Hall element 15. is doing.
The fixing unit 6 has a DMD cover 17 attached to the upper side of the DMD 2, a top plate 21, a base plate 25, a support plate 22, and a fourth fixing plate 29, which are first to fourth fixing plates.
The fixing unit 6 also has a position detection magnet 32, a control board 19, a drive magnet 23, and a support column 26.
The fixed unit 6 is fixedly supported by the housing of the image forming apparatus.

It should be noted that the number and positions of the columns 26 and the ball support portions 28 provided in the illustrated fixed unit 6 are not limited to the configurations exemplified in this embodiment as long as the movable plate 11 can be movably supported.

By the way, when the DMD2 is operated by the control board 19 to increase the resolution, a method of moving the DMD2 together with the movable plate 11 in parallel on the XY plane by half a pixel to form an intermediate image in the projected image is conceivable. Be done.
Therefore, in the present embodiment, a current is passed through the coil 12 via the driving FPC 16 based on the control from the control board 19.
At this time, a Lorentz force is generated as a driving force by the current flowing through the coil 12 with respect to the steady magnetic field generated by the driving magnet 23.
Since the driving magnet 23 is fixed and immovable, the Lorentz force applied acts in the direction of operating the coil 12 on the XY plane. That is, the entire movable unit 5 fixed to the coil 12 is driven according to the Lorentz force generated by the coil 12.
The magnitude and direction of the current flowing through each coil 12 is controlled by the movement control unit 92 of the system control unit 90 on the control board 19. The movement control unit 92 controls the movement (rotation) direction, movement amount, rotation angle, and the like of the movable plate 11 according to the magnitude and direction of the current flowing through the coil 12.

When the position of the movable unit 5 changes, the Hall element 15 converts the change in magnetic flux density into an electromotive force and transmits the change to the control board 19 via the position detection FPC 18.
Since the magnetic force of the drive magnet 23 is known and the Lorentz force acting on the coil 12 is variable depending on the amount of current flowing through the coil 12, the control board 19 controls the amount of current flowing through the coil 12 according to the position. The position of the movable unit 5 is controlled.

Even if the movable unit 5 operates with respect to the fixed unit 6, the sliding resistance is changed to the rolling resistance by the ball 24, and the position detection FPC 18 and the driving FPC 16 have flexibility. The movable unit 5 can be operated by a desired distance without adversely affecting the function of the image display unit 1.

In the present embodiment, the drive magnet 23 and the position detection magnet 32, which are permanent magnets that generally tend to increase the weight, are fixed to the housing as the fixing unit 6. According to such a configuration, the weight of the movable unit 5 can be reduced and the position of the movable unit 5 can be efficiently controlled.
Further, according to the concept of the magnetic circuit, it is desirable that the top plate 21 and the fourth fixing plate 29, which are members for attaching the driving magnet 23 and the position detection magnet 32, are both magnetic sheet metal.
Further, the base plate 25 as the second and third fixing plates and the support plate 22 have no functional limitation regardless of whether they are magnetic or non-magnetic, but in the present embodiment, the magnetic force generated by the driving magnet 23 is used. Since it is larger than the position detection magnet 32, the support plate 22 is also made of magnetic sheet metal so that the leakage flux does not adversely affect the Hall element 15.
With this configuration, the magnetic field created by the drive magnet 23 is shielded by the support plate 22, so that the magnetic field created by the drive magnet 23 does not leak and adversely affect the Hall element 15, so that the position of the movable unit 5 is accurately positioned. Can be detected.

Since the DMD 2 is a reflective optical element in which micromirrors are arranged for each pixel, there are many driven portions, and there is a concern that the temperature of the image display unit 1 will rise.
Further, in order to achieve the above-mentioned high resolution, the coil 12 is driven by passing a current, so that the heat generated by the coil 12 is also added.
Therefore, a configuration is considered in which a heat sink is attached to the movable unit side as the enlarged cooling unit. However, since the movable unit 5 side is non-magnetic and has a large restriction on weight, aluminum material is often used, and simply attaching a heat sink is between the coil 12 and the DMD 2. There was also a problem that the heat generated in the coil 12 warmed the DMD2 because the thermal resistance hardly worked.

In order to solve such a problem, for example, it is conceivable to attach another cooling device that uses a refrigerant or the like to cool the coil 12, but it is desirable because the configuration becomes complicated and the wiring to the movable unit 5 becomes complicated. do not have.

Therefore, in the present embodiment, as shown in FIG. 10, the image display unit 1 includes fins 141 arranged on the surface opposite to the surface on which the coil 12 of the base 140 and the driving magnet 23 face each other. It has an opening 142 that penetrates from the fin 141 side of the substrate of the heat sink 14 to the surface where the coil 12 and the driving magnet 23 face each other, and blowers 41a and 41b that send air toward the fin 141.
With such a configuration, the image display unit 1 has a function as a movable cooling device.
That is, in other words, in the present embodiment, the opening 142 formed so as to penetrate the base 140 and the coil 12 provided facing the driving magnet 23 form an air flow path used for cooling. It has blowers 41a and 41b that send air toward the fins 141 through the flow path.

(Movable cooling device)
The blowers 41a and 41b will be described in detail.
Both the blowers 41a and 41b are blowers that form an air flow in a predetermined direction from the outlet 411, here in the X direction, by the rotation of the cooling fan 410. In the present embodiment, in particular, the blower 41a is a PUSH type or blow type blower, and the blower 41b is a PULL type or suction type blower, but the configuration is not limited to this, and only one of them is provided. May be. In the following description, the blower 41a will be particularly described for simplification, but the blower 41b also has the same configuration except for the direction of the air flow. Since both the PUSH type and the PULL type have fins 141 on the path of the air flow to be formed, it can be said that the configuration is such that "air is sent toward the fins 141".

As already mentioned, the coil 12 is attached to the opening 143 of the heat sink 14. With this configuration, the air blown from the blower 41a cools the fins 141 and also the coil 12.
Further, the fins 141 are formed along the X direction in which the cooling fan 410 blows air so as to form the wall surface of the air flow path 144.
According to such a configuration, since the flow path 144 is formed without obstructing the air flow of the cooling air, the cooling air can be efficiently cooled without impairing the wind speed of the cooling air discharged by the blower 41a.

Further, in the present embodiment, the air core of the coil 12 is arranged so as to form a part of the air flow path 144.
According to this configuration, the air blown by the cooling fan 410 passes over the base 140 of the heat sink 14 to cool it, and at the same time, it passes through the air core of the coil 12 to cool the coil 12 at the same time. can.

Further, fins 141 are not provided in the range connecting the air outlet 411 of the blower 41a to the air core of the coil 12.
With such a configuration, the cooling air is blown to the coil 12 before being heated by the fins 141 of the heat sink 14, so that the coil 12 can be efficiently cooled.

Further, in the present embodiment, the thickness of the coil 12 in the Z direction is thicker than the thickness of the base 140 of the heat sink 14.
That is, in the present embodiment, as shown in FIG. 11, the coil 12 is arranged so as to project from the base 140 of the heat sink 14 in the −Z direction, that is, in the extending direction of the fin 141 when viewed from the X direction.
With this configuration, the surface area of the coil 12 that comes into contact with the cooling air is increased, so that the cooling efficiency is increased and the number of turns of the coil 12 can be easily increased, which is necessary to receive the Lorentz force of the same strength. It is also possible to keep the amount of current small and reduce the amount of heat generated proportionally with RI ² .

Further, in the present embodiment, a distance d equal to or larger than the pitch p of the fins 141 is provided between the coil 12 and the driving magnet 23.
According to this configuration, the cooling air passes through the air core of the coil 12, further increasing the area in which the cooling air comes into contact with the coil 12, and contributing to the improvement of the cooling efficiency.

This point will be described in more detail.
In general, it can be said that the cooling air passing through the flow path 144 flows through the flow path that is most easily flowed from the viewpoint of ventilation resistance. Here, the ventilation resistance decreases as the cross-sectional area of the portion through which the cooling air flows is larger, and increases as the cross-sectional area is smaller.
That is, if the air core of the coil 12 is not large enough, or if the distance d between the coil 12 and the driving magnet 23 is shorter than the pitch p between the fins 141, the inside of the air core is cooled. Since it becomes difficult for the wind to pass through, the surface of the coil 12 on the inner peripheral side becomes difficult to come into contact with the cooling air.
Therefore, in the present embodiment, the cooling efficiency is further improved by leaving a space d between the coil 12 and the driving magnet 23, which is equal to or greater than the pitch p of the fins 141.

By keeping the distance d between the coil 12 and the drive magnet 23 in this way, the radiant heat transmitted from the coil 12 to the drive magnet 23 should be reduced, so that the heat of the drive magnet 23 is used. Demagnetization can also be suppressed.

Further, in the present embodiment, the coil 12 has an air core, and the air core is arranged on an opening 143 formed so as to penetrate the base 140 of the heat sink 14.
With such a configuration, the cooling air can be expected to have the effect of cooling not only the coil 12 but also the driving magnet 23, so that the cooling can be performed more efficiently.

Further, in order to enhance the cooling effect of the DMD 2, an elastically deformable heat transfer sheet may be provided between the base 140 of the heat sink 14 and the DMD 2. The heat transfer sheet improves the thermal conductivity between the heat sink 14 and the DMD2, and the heat sink 14 improves the cooling effect of the DMD2.

(Image projection)
As described above, in the projector 100 according to the present embodiment, the DMD 2 that generates the projected image is provided in the movable unit 5, and the position is controlled together with the movable unit 5 by the movement control unit 92 of the system control unit 90. ..

The movement control unit 92 moves at high speed between a plurality of positions separated by a distance less than the arrangement interval of the plurality of micromirrors of the DMD2 at a predetermined cycle corresponding to the frame rate at the time of image projection, for example. Control the position of. At this time, the image control unit 91 transmits an image signal to the DMD 2 so as to generate a projected image shifted according to each position.

For example, the movement control unit 92 reciprocates the DMD2 in a predetermined cycle between the position P1 and the position P2 separated by a distance less than the arrangement interval of the micromirrors of the DMD2 in the ± X direction and the ± Y direction. At this time, the image control unit 91 controls the DMD2 so as to generate a projected image shifted according to each position, so that the resolution of the projected image can be made about twice the resolution of the DMD2. Become. Further, by increasing the moving position of the DMD2, the resolution of the projected image can be doubled or more than that of the DMD2.

In this way, the movement control unit 92 moves the DMD2 together with the movable unit 5 in a predetermined cycle, and the image control unit 91 causes the DMD2 to generate a projection image according to the position, thereby projecting an image having a resolution higher than that of the DMD2. Will be possible.

Although the preferred embodiment has been described in detail above, it is not limited to the above-described embodiment, and various modifications and substitutions are made to the above-mentioned embodiment without departing from the scope of the claims. Can be added.
For example, in the present embodiment, only the example of the projector as the image projection device has been described, but the same configuration may be used for the image projection device that projects the image information by the projected light.

1 Image display unit (movable cooling device)
2 Image display element (DMD)
3 Position detection unit 4 Driving force generation unit 5 Movable unit 6 Fixed unit 11 Movable plate 12 Coil
14 Enlarged cooling unit (heat sink)
15 Hall element 21, 22, 25, 29 Fixed plate 41 (41a, 41b) Blower 60 Projection optical system 100 Image projection device 115 Optical engine 140 Base 141 Fin 142 Support 143 Opening

Japanese Unexamined Patent Publication No. 2017-167496 JP-A-2017-102174 JP-A-2017-227715 Japanese Unexamined Patent Publication No. 2008-228545

Claims (4)

Movable plate and
A heat sink configured to include a substrate on which fins are arranged and connected to the movable plate,
Two fixing plates, one of which is arranged between the movable plate and the heat sink and which movably holds the movable plate between the one and the other.
A magnet arranged on the heat sink side fixing plate of the two fixing plates, and
An opening formed in the heat sink and penetrating the substrate, and a coil having an air core arranged in the opening and opposed to the magnet.
The fins arranged on the surface opposite to the surface on the side where the magnet and the coil of the substrate face each other, and the fins.
It is equipped with a blower that blows air toward the fins.
The fins are extended in a direction along the air sent by the blower to form a flow path for the air, and the fins are within a range connecting the blower and the air core of the coil in the flow path. Not provided,
The distance between the coil and the magnet is larger than the distance between the adjacent fins.
A movable cooling device characterized by that . In the movable cooling device according to claim 1,
A movable cooling device characterized in that the thickness of the coil is thicker than the thickness of the substrate of the heat sink . The movable cooling device according to claim 1 or 2 ,
An image generation device including an image display element attached to the movable plate. The movable cooling device according to claim 1 or 2,
The image display element attached to the movable plate and
A projection optical system for projecting an image displayed on the image display element, and
Image projection device with.

Images