阅读说明：本技术 投射光学装置和投影仪 (Projection optical device and projector ) 是由 泷泽孝浩 于 2021-04-20 设计创作，主要内容包括：提供投射光学装置和投影仪,提高冷却性。投射光学装置具有：第1壳体；第2壳体,其收纳于第1壳体；以及投射光学系统,其收纳于第2壳体。投射光学系统具有第1反射元件,该第1反射元件使投射光学系统的光路弯折。第1壳体具有多个第1开口部,该多个第1开口部将第1壳体的内外连通。第2壳体具有多个第2开口部,该多个第2开口部将第2壳体的内外连通。(Provided are a projection optical device and a projector, which can improve cooling performance. The projection optical device includes: 1, a first shell; a2 nd case housed in the 1 st case; and a projection optical system housed in the 2 nd housing. The projection optical system has a1 st reflection element, and the 1 st reflection element bends an optical path of the projection optical system. The 1 st case has a plurality of 1 st openings, and the plurality of 1 st openings communicate the inside and outside of the 1 st case. The 2 nd case has a plurality of 2 nd opening portions, and the plurality of 2 nd opening portions communicate the inside and outside of the 2 nd case.)

1. A projection optical apparatus, comprising:

1, a first shell;

a2 nd case housed in the 1 st case; and

a projection optical system housed in the 2 nd housing,

the projection optical system has a1 st reflection element which bends an optical path of the projection optical system,

the 1 st case has a plurality of 1 st openings, the plurality of 1 st openings communicating the inside and outside of the 1 st case,

the 2 nd case has a plurality of 2 nd opening portions, and the plurality of 2 nd opening portions communicate the inside and the outside of the 2 nd case.

2. Projection optical device according to claim 1,

at least one of the plurality of 2 nd opening portions is provided at a position opposed to at least one of the plurality of 1 st opening portions.

3. Projection optical device according to claim 1 or 2,

the 2 nd enclosure releases heat of the projection optical system from a2 nd opening portion arranged in a direction opposite to a vertical direction among the plurality of 2 nd opening portions, and sucks air outside the 2 nd enclosure from other 2 nd opening portions among the plurality of 2 nd opening portions.

4. Projection optical device according to claim 1 or 2,

the projection optical device further includes a heat dissipation portion provided to the 1 st reflecting element and exposed to the outside of the 2 nd housing.

5. A projection optical apparatus, comprising:

1, a first shell;

a2 nd case housed in the 1 st case;

a projection optical system housed in the 2 nd housing; and

a heat dissipating part exposed to the outside of the 2 nd case,

the projection optical system has a1 st reflection element which bends an optical path of the projection optical system,

the 1 st case has a plurality of 1 st openings, the plurality of 1 st openings communicating the inside and outside of the 1 st case,

the heat dissipation portion is disposed on the 1 st reflective element.

6. Projection optical device according to claim 1 or 5,

the projection optical system has: a1 st lens group disposed on an enlargement side of the 1 st reflective element; a2 nd reflecting element disposed on a reduction side of the 1 st reflecting element; and a2 nd lens group disposed on the reduction side of the 2 nd reflective element,

the 1 st reflecting element and the 2 nd reflecting element bend the light path to make a1 st optical axis of the 1 st lens group and a2 nd optical axis of the 2 nd lens group approximately parallel.

7. Projection optical device according to claim 1 or 5,

two 1 st openings of the plurality of 1 st openings are opposed to each other in the 1 st direction,

the other two 1 st openings of the plurality of 1 st openings face each other in a2 nd direction intersecting the 1 st direction.

8. Projection optical device according to claim 1 or 5,

the projection optical device further includes a plurality of dust-proof members provided at the plurality of No. 1 openings, respectively,

the air inside and outside the 1 st case flows through the plurality of dust-proof members.

9. Projection optical device according to claim 1 or 5,

the material of the 2 nd shell is resin.

10. A projector, characterized by having:

a light source device;

a light modulation device that modulates light emitted from the light source device; and

the projection optical device according to any one of claims 1 to 9, which projects the light modulated by the light modulation device.

Technical Field

The present invention relates to a projection optical device and a projector.

Background

Conventionally, a bending type projection optical device applied to a projection type display device such as a projector is known. Such a projection optical device is provided with optical components such as a projection lens and a mirror for changing the projection direction of a display image to be projected. For example, patent document 1 discloses a projection optical system including a lens group as an optical member and two mirrors as an optical path folding means.

Patent document 1: japanese patent laid-open publication No. 2016-156986

However, the projection optical system of patent document 1 has a problem that the temperature in the system becomes high. In detail, when a high-beam image light or the like is projected using the projection optical system, the optical components and the atmosphere tend to reach high temperatures. Therefore, the temperature of the member holding the optical member may rise to cause thermal expansion, which may degrade the positional accuracy of the optical member. When the positional accuracy is lowered, the display quality of a projected image or the like is liable to deteriorate. In particular, in a bending type projection optical system, the optical axis deviates by an angle 2 times the incident angle according to snell's law, and therefore, deterioration of display quality may become significant. That is, a projection optical device having improved cooling performance of the interior than the conventional one is required.

Disclosure of Invention

The projection optical device includes: 1, a first shell; a2 nd case housed in the 1 st case; and a projection optical system housed in the 2 nd housing. The projection optical system has a1 st reflection element, and the 1 st reflection element bends an optical path of the projection optical system. The 1 st case has a plurality of 1 st openings, and the plurality of 1 st openings communicate the inside and outside of the 1 st case. The 2 nd case has a plurality of 2 nd opening portions, and the plurality of 2 nd opening portions communicate the inside and the outside of the 2 nd case.

The projection optical device includes: 1, a first shell; a2 nd case housed in the 1 st case; a projection optical system housed in the 2 nd housing; and a heat dissipation portion exposed to the outside of the 2 nd case. The projection optical system has a1 st reflection element, and the 1 st reflection element bends an optical path of the projection optical system. The 1 st case has a plurality of 1 st openings, and the plurality of 1 st openings communicate the inside and outside of the 1 st case. The heat dissipation portion is disposed on the 1 st reflective element.

The projector includes: a light source device; a light modulation device that modulates the light emitted from the light source device; and the projection optical device that projects the light modulated by the light modulation device.

Drawings

Fig. 1 is a schematic diagram showing a configuration of a projector according to embodiment 1.

Fig. 2 is a perspective view showing an appearance of the projection optical apparatus.

Fig. 3 is a schematic diagram showing the structure of the projection optical apparatus.

Fig. 4 is a perspective view showing an appearance of the frame.

Fig. 5 is a perspective view showing an appearance of the frame.

Fig. 6 is a schematic diagram showing the structure of the air flow path.

Fig. 7 is a schematic diagram showing the structure of the air flow path.

Fig. 8 is a schematic diagram showing the structure of the air flow path.

Fig. 9 is a perspective view showing the arrangement of a heat dissipation part of the projection optical device of embodiment 2.

Description of the reference symbols

1: a projector; 10: a light source device; 40R, 40G, 40B: a liquid crystal panel as a light modulation device; 60: a projection optical device; 61: a lens barrel as a1 st housing; 600: a projection optical system; 611: a1 st reflective element; 613: a1 st lens group; 621: a2 nd reflecting element; 623: a2 nd lens group; 630. 930: a frame as a2 nd case; 661. 661a, 661b, 661c, 661 d: 1 st opening part; 662a1, 662a2, 662b1, 662b2, 662c, 662 d: a2 nd opening part; 664: a dust-proof member; 911: a heat dissipating section; a1: the optical axis of the 1 st lens group; a2: the optical axis of the 2 nd lens group; l: light is synthesized.

Detailed Description

In the following drawings, XYZ axes orthogonal to each other are indicated as necessary, and the direction indicated by each arrow is defined as a + direction and a direction opposite to the + direction is defined as a-direction. In the following description, the + Z direction may be referred to as "up" and the-Z direction may be referred to as "down".

1. Embodiment 1

1.1. Projector structure

In the present embodiment, a projector 1 having 3 liquid crystal panels as light modulation devices is exemplified. First, the configuration of the projector 1 according to embodiment 1 will be described with reference to fig. 1.

As shown in fig. 1, the projector 1 includes a light source device 10, a color separation optical system 20, a relay optical system 30, liquid crystal panels 40R, 40G, and 40B as light modulation devices, a color combining optical system 50, and a projection optical device 60 inside a main body 2. The liquid crystal panels 40R, 40G, and 40B modulate light emitted from the light source device 10. The projection optical device 60 projects the light modulated by the liquid crystal panels 40R, 40G, and 40B. The projection optical device 60 is an example of the projection optical device of the present invention.

The light source device 10 has a light source 11. The light source 11 is a discharge type lamp and emits light to the color separation optical system 20. An integrator optical system, not shown, including a fly-eye lens, a polarization conversion element, and the like is provided between the light source 11 of the light source device 10 and the color separation optical system 20. The light source 11 is not limited to a discharge lamp, and may be a solid-state light source such as a light emitting diode or a laser.

The color separation optical system 20 includes dichroic mirrors 21 and 22, a reflecting mirror 23, and field lenses 24 and 25. Light entering the color separation optical system 20 from the light source device 10 is separated into 3 color lights of different wavelength bands by dichroic mirrors 21 and 22. The 3-color colored light is R light which is substantially red light, G light which is substantially green light, and B light which is substantially blue light.

The dichroic mirror 21 transmits the R light and reflects the G light and the B light. The R light transmitted through the dichroic mirror 21 is reflected by the reflecting mirror 23, and passes through the field lens 24 to illuminate the liquid crystal panel 40R for the R light.

The dichroic mirror 22 transmits the B light and reflects the G light. The G light reflected by the dichroic mirror 22 passes through the field lens 25 and illuminates the liquid crystal panel 40G for G light. The B light transmitted through the dichroic mirror 22 enters the relay optical system 30.

The relay optical system 30 includes an incident side lens 31, mirrors 32 and 34, a relay lens 33, and an exit side lens 35 as a field lens. The optical path of the B light is longer than that of the R light and the G light, and the light flux tends to increase. Therefore, the enlargement of the light beam can be suppressed by the relay lens 33. The B light incident from the color separation optical system 20 is reflected by the mirror 32, and converged by the incident side lens 31 in the vicinity of the relay lens 33. Then, the B light diverges toward the mirror 34 and the exit side lens 35. The B light reflected by the reflecting mirror 34 passes through the exit side lens 35 to illuminate the liquid crystal panel 40B for the B light.

The liquid crystal panels 40R, 40G, and 40B convert the color light incident from the respective incidence surfaces into light having an intensity corresponding to the corresponding image signal, and emit the converted light to the color combining optical system 50. As the liquid crystal panels 40R, 40G, and 40B, transmissive liquid crystal panels are used.

The liquid crystal panels 40R, 40G, and 40B as the light modulation devices are not limited to transmissive ones, and may be reflective ones. Further, as the light modulation device, a digital micromirror device or the like may be used. Further, the configuration is not limited to the configuration in which the light modulation device is provided for each of the plurality of color lights, and the plurality of color lights may be modulated in a time division manner by 1 light modulation device.

The color combining optical system 50 is a cross dichroic prism, and combines the converted light of each color incident from the liquid crystal panels 40R, 40G, and 40B. Thereby, the 3-color converted light of the R light, the G light, and the B light generates the combined light L, which displays a color image. The combined light L is emitted toward the projection optical device 60.

The projection optical device 60 is attached to the main body 2 via a lens mount 70. The projection optical device 60 is detachable from the main body 2. The synthesized light L incident on the projection optical device 60 is enlarged and displayed as image light on a projection target such as a screen not shown via the projection optical device 60.

1.2. Structure of projection optical device

The structure of the projection optical device 60 will be described with reference to fig. 2 and 3. In fig. 3, the projection optical device 60, the color combining optical system 50 of the main body 2, and the lens mount 70 are not shown.

As shown in fig. 2, the projection optical device 60 is a bending type projection lens, and has an optical system that is bent in a substantially U shape when viewed from the + X direction side in plan view. A cylindrical portion 62 is provided at the lower end of the projection optical device 60 in the-Y direction. When the projection optical device 60 is attached to the main body 2, the cylindrical portion 62 is inserted into the lens attachment portion 70.

An openable and closable lens cover 64 is provided at an upper end of the projection optical device 60. Fig. 2 shows a state in which the lens cover 64 is closed. The lens cover 64 opens and emits image light when the projection optical device 60 is used, and closes to protect the inside of the projection optical device 60 when the projection optical device 60 is not used. The lens cover 64 may be detachable from the projection optical device 60.

A lens barrel 61 as a1 st housing is provided between the cylindrical portion 62 and the lens cover 64. A frame or the like as a2 nd case described later is housed in the lens barrel 61.

The lens barrel 61 is provided with a plurality of 1 st openings 661a, 661b, 661c, 661d, and the plurality of 1 st openings 661a, 661b, 661c, 661d communicate the inside and outside of the lens barrel 61. In the following description, the 1 st openings 661a, 661b, 661c, 661d will be collectively referred to as the 1 st opening 661. The 1 st opening 661 has a substantially rectangular shape in plan view.

Of the 1 st openings 661, 21 st openings 661a and 661b are opposed to each other in the 1 st direction along the X axis. Specifically, in the lens barrel 61, the 1 st opening 661a is disposed on the side surface in the + X direction, and the 1 st opening 661b is disposed on the side surface in the-X direction. Of the 1 st openings 661, 21 st openings 661c and 661d are opposed to each other in a direction along the Z axis, which is a2 nd direction intersecting with the direction along the X axis. Specifically, in the lens barrel 61, the 1 st opening 661c is disposed above and the 1 st opening 661d is disposed below.

Here, in the present embodiment, the mode in which the lens barrel 61 has 4 1 st openings 661 is exemplified, but the present invention is not limited to this. The number of the 1 st openings 661 may be 5 or more, at least two of which face each other in the 1 st direction, and at least 2 of which face each other in the 2 nd direction. Further, the 1 st direction and the 2 nd direction are not limited to the direction along the X axis and the direction along the Z axis. The 1 st direction and the 2 nd direction may be, for example, two directions intersecting each other on a plane along the X-Z plane.

The 1 st opening 661 is provided with a dust-proof member 664. The air inside and outside the lens barrel 61 flows through the inside of the lens barrel 61 and the outside via the dust-proof member 664. The dust-proof member 664 is, for example, a felt-made or paper-made dust-proof filter formed by molding fibers in a plate shape.

As shown in fig. 3, the cylindrical portion 62 of the projection optical device 60 is inserted into the lens mount portion 70 and attached to the main body portion 2. The combined light L emitted from the color combining optical system 50 in the + Y direction enters the projection optical device 60 from the end surface of the cylindrical portion 62 in the-Y direction.

The projection optical device 60 includes a projection optical system 600 and a frame 630 as a2 nd housing in the barrel 61, and the frame 630 accommodates the projection optical system 600. The projection optical device 60 bends the combined light L incident from the color combining optical system 50 in two stages in sequence. Therefore, the combined light L is inverted in the-Y direction of the projector 1 and emitted as image light.

The projection optical system 600 has a1 st reflecting element 611, a2 nd reflecting element 621, a1 st lens group 613, and a2 nd lens group 623. The 1 st reflecting element 611 and the 2 nd reflecting element 621 bend the optical path of the combined light L. The 1 st lens group 613 is disposed at the rear stage of the 1 st reflective element 611. The 2 nd reflective element 621 is disposed at a front stage of the 1 st reflective element 611. The 2 nd lens group 623 is disposed at a front stage of the 2 nd reflective element 621. The 1 st reflecting element 611 is arranged on the X-Y plane so that the end in the-Y direction stands up at about 45 degrees. The 2 nd reflecting element 621 is arranged on the X-Y plane so that the end in the + Y direction rises by about 45 degrees.

In the present specification, the front stage means a side close to the light source device 10, and the rear stage means a side far from the light source device 10, that is, a side close to the projection target. Therefore, the front stage is the reduction side of the projection optical system 600, and the rear stage is the enlargement side of the projection optical system 600. That is, the 2 nd lens group 623, the 2 nd reflecting element 621, the 1 st reflecting element 611, and the 1 st lens group 613 are arranged in this order in the traveling direction of the combined light L in each configuration of the projection optical system 600. In fig. 3, only the lens closest to the color combining optical system 50 in the 2 nd lens group 623 is shown, only the lens closest to the projection target in the 1 st lens group 613 is shown, and the other lenses are omitted.

The lens barrel 61 accommodates a frame 630 as a2 nd housing therein. The frame 630 accommodates a1 st reflecting element 611 and a2 nd reflecting element 621. Here, in fig. 3, a structure in which the 1 st reflective element 611 and the 2 nd reflective element 621 are housed in the frame 630 in the projection optical system 600 is shown, but it is not limited thereto. The frame 630 may also be configured to house the 1 st lens group 613 and the 2 nd lens group 623. Details of the framework 630 are described later.

The 1 st and 2 nd reflective elements 611 and 621 bend the optical path of the combined light L such that the optical axis a1 of the 1 st lens group is substantially parallel to the optical axis a2 of the 2 nd lens group. In detail, the combined light L incident on the projection optical device 60 travels along the optical axis a2 of the 2 nd lens group 623 and reaches the 2 nd reflecting element 621. The 2 nd reflecting element 621 bends the combined light L by reflecting the combined light L in a direction substantially along the Z axis, with the direction substantially perpendicular to the optical axis a 2. The combined light L reflected by the 2 nd reflecting element 621 reaches the 1 st reflecting element 611. The 1 st reflecting element 611 reflects the combined light L in a direction substantially perpendicular to the Z axis and substantially along the Y axis to bend the combined light L. The combined light L reflected by the 1 st reflecting element 611 travels along the optical axis a1 and is incident on the 1 st lens group 613.

The 1 st lens group 613 magnifies the beam of the combined light L incident from the + Y direction and emits it in the-Y direction. The combined light L emitted from the 1 st lens group 613 is magnified as image light and obliquely projected from the projection optical device 60 in the-Y direction above the projector 1.

Here, the 3 rd lens group may be disposed on the optical path between the 1 st reflective element 611 and the 2 nd reflective element 621. According to the 3 rd lens group, the light beam of the combined light L reflected by the 2 nd reflecting element 621 and directed toward the 1 st reflecting element 611 can be widened or converged.

The 1 st openings 661c and 661d face each other in the direction along the Z axis through the frame 630. The 1 st openings 661a and 661b face each other in the X-axis direction through the frame 630. The 1 st opening 661 is exposed to the outside in a state where the projection optical device 60 is attached to the projector 1, and communicates the inside of the lens barrel 61 with the outside. Further, a plurality of 2 nd openings, which will be described later, provided in the frame 630 are provided at positions corresponding to any one of the 1 st openings 661.

The projection optical device 60 makes the projector 1 short-coked compared to a projection lens that is not a bending type. By using the curved projection optical device 60, projection can be performed at a position close to the projection target. The bending type projection optical device 60 is not limited to the above configuration, as long as the optical path of the combined light L emitted from the main body 2 can be bent and emitted.

1.3. Structure of frame

The structure of the frame 630 will be described with reference to fig. 4 and 5. As shown in fig. 4 and 5, the frame 630 has a substantially trapezoidal shape in which the lower base in the-Y direction is longer than the upper base in the + Y direction when viewed from the + X direction in plan. The frame 630 is a quadrangular prism having the trapezoid as the bottom surface, and the direction along the X axis coincides with the height direction of the quadrangular prism. The area corresponding to the lower bottom is in a rectangular frame shape when viewed from a-Y direction in plan.

As described above, the frame 630 is substantially quadrangular prism-shaped, and the face in the-Y direction is open. The frame 630 has a1 st window portion 631 and a2 nd window portion 632. At a portion corresponding to the waist of the trapezoid, a1 st window 631 is provided on the upper surface, and a2 nd window 632 is provided on the lower surface. The 1 st reflecting element 611 is disposed in the 1 st window 631, and the 2 nd reflecting element 621 is disposed in the 2 nd window 632. The 1 st reflective element 611 and the 2 nd reflective element 621 are fixed to the frame 630, for example, by adhesion. The adhesive is, for example, an ultraviolet-curable adhesive.

The 1 st reflecting surface 611a of the 1 st reflecting element 611 is exposed to the-Y direction of the frame 630, that is, to the inside of the frame 630, through the 1 st window 631. Further, the 2 nd reflecting surface 621a of the 2 nd reflecting element 621 is exposed to the inside of the frame 630 through the 2 nd window portion 632. The optical path of the combined light L described above is formed in the inner space inside the frame 630 by the 1 st and 2 nd reflecting surfaces 611a and 621 a.

Specifically, the combined light L passes through the 2 nd lens group 623 and reaches the 2 nd reflecting element 621 through the 2 nd window portion 632. Then, the combined light L is reflected in the + Z direction by the 2 nd reflecting element 621, passes through the 1 st window portion 631, and reaches the 1 st reflecting element 611. Then, the combined light L reflected by the 1 st reflecting element 611 travels in the-Y direction through the 1 st window portion 631, and enters the 1 st lens group 613.

The frame 630 is provided with a plurality of 2 nd openings 662a1, 662a2, 662b1, 662b2, 662c, 662d, and the plurality of 2 nd openings 662a1, 662a2, 662b1, 662b2, 662c, 662d communicate the inside and the outside of the frame 630, that is, the inside and the outside of the frame 630. The 2 nd openings 662a1, 662a2, 662b1 and 662b2 are communication holes that are substantially triangular in plan view. The 2 nd openings 662c and 662d are communication holes that are substantially rectangular in plan view. In the following description, the plurality of 2 nd openings 662a1, 662a2, 662b1, 662b2, 662c, 662d are also collectively referred to as the 2 nd openings 662.

The 2 nd openings 662a1 and 662a2 are provided in the trapezoidal shape in the + X direction, i.e., the side surface in the + X direction, and the 2 nd openings 662a1 and 662a2 are arranged in this order downward. The 2 nd openings 662b1 and 662b2 are provided on the trapezoidal shape in the-X direction, i.e., on the side surface in the-X direction, and the 2 nd opening 662b1 and the 2 nd opening 662b2 are arranged in this order downward. The 2 nd opening 662a1 and the 2 nd opening 662b1, and the 2 nd opening 662a2 and the 2 nd opening 662b2 face each other in the direction along the X axis.

The 2 nd opening 662c is provided in the frame-shaped area above the frame 630. The 2 nd opening 662d is provided in the frame-shaped area below the frame 630. The 2 nd opening 662c and the 2 nd opening 662d face each other in the direction along the Z axis.

The 2 nd opening portions 662 may be provided with dust-proof members similar to the dust-proof members 664 of the 1 st opening portion 661. This further reduces dust contained in the air taken in from the outside, and can prevent the dust from adhering to the optical components such as the 1 st reflecting element 611 and the 2 nd reflecting element 621.

In the present embodiment, the embodiment having 62 nd openings 662 is exemplified, but the shape, number, size, and arrangement thereof are not limited.

Examples of the material of the frame 630 include resins such as an acrylonitrile-butadiene-styrene copolymer resin, a polycarbonate resin, a polyacetal resin, a polyphenylene ether resin, a polybutylene terephthalate resin, a polysulfone resin, a polyether ether ketone resin, a fluororesin, an aromatic polyester resin such as a liquid crystal polymer, and a polyphenylene sulfide resin. The frame 630 may contain a filler such as glass fiber, an additive, and the like in addition to these resins.

1.4. Structure of air flow path

The air flow path in the projection optical device 60 will be described with reference to fig. 6 to 8. The air flow path mentioned here is a path for cooling heat generated in the optical components and the like when the projection optical device 60 is used, by an air flow of air generated by a so-called chimney effect. Since the air flow path changes in accordance with the installation posture of the projection optical device 60, air flow paths corresponding to 3 installation postures are exemplified.

1.4.1. Flatly placed device

When the projector 1 to which the projection optical device 60 is attached is placed flat, the direction from the 2 nd opening 662c to the 2 nd opening 662d, that is, the-Z direction, substantially coincides with the vertical direction. In this case, the buoyancy of the high-temperature air due to the chimney effect acts in the + Z direction, which is a direction opposite to the vertical direction.

As shown in fig. 6, when the optical component reaches a high temperature, the air around the optical component is heated, and an air flow fa of the air is generated inside the frame 630. The air flow fa is discharged to the outside of the frame 630 through the 2 nd opening 662c in the upward direction. Then, the air flow fa flows out to the outside of the projection optical device 60 through the 1 st opening 661c above the lens barrel 61. At this time, the air outside the frame 630 flows into the frame 630 from the 2 nd opening 662 except the 2 nd opening 662c in accordance with the flow fa.

Specifically, an air flow fa1 passing through the 2 nd opening 662a1, an air flow fa2 passing through the 2 nd opening 662a2, an air flow fa3 passing through the 2 nd opening 662b1, an air flow fa4 passing through the 2 nd opening 662b2, and an air flow fa5 passing through the 2 nd opening 662d are generated. The airflows fa1 and fa2 are airflows of relatively cool air flowing from the outside of the projection optical device 60 through the 1 st opening 661a of the lens barrel 61. Similarly, the airflows fa3 and fa4 are airflows of air flowing in through the 1 st opening 661b of the lens barrel 61. The air flow fa5 is an air flow of air flowing in through the 1 st opening 661d of the lens barrel 61.

When the air flows fa1 to fa5 are heated by the heat of the optical components, they become the air flow fa and flow out to the outside of the projection optical device 60. The air flow fa is continuously generated until the optical component is cooled, and releases heat of the optical component to the outside. Thereby, the optical components such as the 1 st reflecting element 611 and the frame 630 are cooled.

1.4.2. Hanging device

When the projector 1 to which the projection optical device 60 is attached is installed suspended from a ceiling or the like, the direction from the 2 nd opening 662d toward the 2 nd opening 662c, that is, the + Z direction, substantially coincides with the vertical direction. In this case, the buoyancy of the high-temperature air due to the chimney effect acts in the-Z direction, which is a direction opposite to the vertical direction.

As shown in fig. 7, when the optical component reaches a high temperature, the surrounding air is heated, and an air flow fb of air is generated. The airflow fb is discharged to the outside of the frame 630 through the 2 nd opening 662d in the-Z direction. The air flow fb is discharged to the outside of the projection optical device 60 through the 1 st opening 661d below the lens barrel 61. At this time, the air outside the frame 630 flows into the inside of the frame 630 from the 2 nd opening 662 except the 2 nd opening 662d in accordance with the air flow fb.

Specifically, an air flow fb1 passing through the 2 nd opening 662a1, an air flow fb2 passing through the 2 nd opening 662a2, an air flow fb3 passing through the 2 nd opening 662b1, an air flow fb4 passing through the 2 nd opening 662b2, and an air flow fb5 passing through the 2 nd opening 662c are generated. The airflows fb1 and fb2 are airflows of relatively cool air flowing from the outside of the projection optical device 60 through the 1 st opening 661a of the lens barrel 61. Similarly, airflows fb3 and fb4 are airflows of air flowing in through the 1 st opening 661b of barrel 61. Airflow fb5 is an airflow of air flowing in through the 1 st opening 661c of barrel 61.

When the air flows fb1 to fb5 are heated by the heat of the optical components, the air flows fb flows out of the projection optical device 60. The air flow fb is continuously generated until the optical component is cooled, and releases heat of the optical component to the outside. Thereby, the optical components such as the 1 st reflecting element 611 and the frame 630 are cooled.

1.4.3. Upright placing device

The case where the projection optical device 60 is placed upright in the projector 1 to which the projection optical device 60 is attached is described below. In this case, the-X direction substantially coincides with the vertical direction, and the buoyancy of the high-temperature air due to the chimney effect acts in the + X direction, which is a direction opposite to the vertical direction.

As shown in fig. 8, when the optical component reaches a high temperature, the air around the optical component is heated, and an air flow fc of the air is generated. The airflow fc is discharged to the outside of the frame 630 through the 2 nd opening portions 662a1 and 662a2 in the + X direction. The airflow fc is discharged to the outside of the projection optical device 60 through the 1 st opening 661a on the side of the lens barrel 61. At this time, the air outside the frame 630 flows into the frame 630 from the 2 nd opening 662 other than the 2 nd openings 662a1 and 662a2 in accordance with the airflow fc.

Specifically, an airflow fc3 passing through the 2 nd opening 662b1, an airflow fc4 passing through the 2 nd opening 662b2, an airflow fc5 passing through the 2 nd opening 662d, and an airflow fc6 passing through the 2 nd opening 662c are generated. The airflows fc3 and fc4 are airflows of relatively cool air flowing from the outside of the projection optical device 60 through the 1 st opening 661b of the lens barrel 61. Similarly, the airflow fc5 is an airflow of air flowing in through the 1 st opening 661d of the lens barrel 61. Airflow fc6 is the airflow of the air flowing in through the 1 st opening 661c of the lens barrel 61.

When the air flows fc3 to fc5 are heated by the heat of the optical components, they become the air flow fb and flow out of the projection optical device 60. The airflow fc is continuously generated until the optical component is cooled, and releases heat of the optical component to the outside. Thereby, the optical components such as the 1 st reflecting element 611 and the frame 630 are cooled.

Here, when the + X direction of the projection optical device 60 is the lower surface side, the optical components and the frame 630 are cooled in the same manner except that the air flow passing through the 2 nd openings 662a1, 662a2, 662b1, and 662b2 is in the opposite direction.

When the 3 rd lens group is disposed inside the frame 630, the 3 rd lens group is disposed so as not to obstruct the air flows fa, fb, fc, and the like of the air. Specifically, for example, a through hole or the like may be provided in a member supporting the 3 rd lens group to secure a flow path.

As described above, the air flow path is formed inside the 1 st opening 661 of the lens barrel 61, the 2 nd opening 662 of the frame 630, and the frame 630, according to the installation posture of the projector 1.

According to the present embodiment, the following effects can be obtained.

The projection optical device 60 can improve the cooling performance of the interior thereof as compared with the conventional one. Specifically, the air flowing into the lens barrel 61 through the 1 st opening 661 flows into the inside of the frame 630 through the 2 nd opening 662. The air flowing into the frame 630 cools the projection optical system 600 such as the 1 st reflection element 611, and is discharged to the outside of the frame 630 through the other 2 nd opening 662. The air discharged to the outside of frame 630 is discharged to the outside of lens barrel 61 through another 1 st opening 661. Therefore, the heat of the projection optical system 600 is released to the outside of the projection optical device 60 by the air flows fa, fb, fc, and the like of the air, thereby cooling the inside of the lens barrel 61. Therefore, the projection optical device 60 with improved cooling performance can be provided. Further, the projector 1 can be provided with improved optical accuracy, improved display quality of the projected image, and the like.

When the projection optical device 60 is applied to the projector 1, the projection direction of the image or the like projected from the projection optical device 60 is bent by about 180 ° when the projection optical device 60 is viewed from the + X direction in plan. Therefore, the degree of freedom in the arrangement of the projector 1 can be improved.

The heat generated inside the projection optical device 60 heats the surrounding air to generate buoyancy. The high-temperature air in which buoyancy is generated is discharged from the 1 st opening 661 closest to the direction opposite to the vertical direction among the plurality of 1 st openings 661. At this time, low-temperature air is sucked into the inside through the other 1 st opening 661. By the so-called chimney effect, the cooling performance inside can be further improved.

Since the dust-proof member 664 is provided in each of the 1 st opening portions 661, the air sucked into the lens barrel 61 is dedusted by the dust-proof member 664. Therefore, dust can be prevented from adhering to the optical components of the projection optical system 600. This can maintain the cleanliness of the optical components such as the 1 st reflecting element 611, and thus maintain the display quality of a projected image or the like when the projection optical device 60 is applied to the projector 1.

Since the material of the frame 630 is resin, the frame 630 can be made lighter than when the material is metal. Further, the frame 630 can be molded by a simple method such as injection molding, which can reduce the processing cost and the like, and can also suppress the material cost to a low level. This can reduce the manufacturing cost and weight of the projection optical device 60.

2. Embodiment 2

In the present embodiment, a projection optical device, which is a curved projection lens applicable to the projector 1, is exemplified as in embodiment 1. In the projection optical device of the present embodiment, the frame structure is different from that of the projection optical device 60 of embodiment 1.

Like the projection optical device 60 according to embodiment 1, the projection optical device according to the present embodiment includes: a lens barrel 61 as a1 st housing; a frame 930 as a2 nd case accommodated in the lens barrel 61; and a projection optical system 600 housed in the frame 930. The projection optical system 600 has a1 st reflection element 611, and the 1 st reflection element 611 bends an optical path. The lens barrel 61 is provided with 1 st openings 661a, 661b, 661c, 661d, and the 1 st openings 661a, 661b, 661c, 661d communicate the inside and outside of the lens barrel 61.

The structure of the frame 930 will be described below with reference to fig. 9. As shown in fig. 9, the frame 930 has substantially the same quadrangular prism shape as the frame 630 of embodiment 1, and is different from the case where the 2 nd opening 662 of the frame 630 is not provided and the heat dissipation portion 911 is provided in the 1 st reflection element 611. Therefore, the same reference numerals are used for the same components as those in embodiment 1, and redundant description is omitted.

The heat dissipation portion 911 includes a base portion 964 and a protruding portion 993. The base portion 964 is a substantially rectangular flat plate like the 1 st reflecting element 611. One of the main surfaces of the base portion 964 is attached so as to be in contact with the outer surface of the 1 st reflecting element 611, in other words, the surface opposite to the 1 st reflecting surface, which is not shown. On the other main surface of the base 964, a protrusion 993 is provided. The protrusion 993 protrudes in the normal direction of the main surface of the base 964, and is formed of a plurality of fins arranged in a matrix shape when the main surface is viewed in plan. Thereby, the heat dissipation portion 911 is exposed to the space outside the frame 930 and inside the lens barrel 61, not shown. Here, the outside of the frame 930 refers to a side to which the base 964 is attached.

Examples of the material of the heat dissipation portion 911 include metals having relatively high thermal conductivity, such as copper and aluminum.

When the projection optical apparatus of the present embodiment is applied to the projector 1, the heat of the 1 st reflecting element 611 reaching a high temperature due to the above-described synthesized light L is propagated to the heat dissipation portion 911. The heat transmitted to the heat dissipation portion 911 is released from the protruding portion 993 by the base portion 964 to make the surrounding air high in temperature. Since the buoyancy of the high-temperature air acts in the direction opposite to the vertical direction, the air flows out from any one of the 1 st openings 661, which is not shown, to the outside in accordance with the installation posture of the projector 1. At this time, the air outside the lens barrel 61 flows into the space between the lens barrel 61 and the frame 930 through the other 1 st opening 661. These air flows are generated while the 1 st reflecting element 611 is cooled, and release the heat of the 1 st reflecting element 611 to the outside. Thereby, the 1 st reflecting element 611 and the like are cooled.

The number, shape, and arrangement of the protruding portions 993 in the heat dissipation portion 911 are not limited to the above-described embodiments. Further, frame 930 may be provided with communication holes such as 2 nd opening 662 of embodiment 1 to cool the optical components inside frame 930.

According to the present embodiment, the following effects can be obtained.

In a projection optical device, the cooling performance of the interior can be improved compared with the prior art. Specifically, the air that has flowed into the interior of the lens barrel 61 through the 1 st opening 661 cools the heat dissipation portion 911, and is discharged to the outside of the lens barrel 61 through the other 1 st opening 661. Therefore, the heat of the 1 st reflecting element 611 is released to the outside by the air flow of the air, thereby cooling the inside. This can provide a projection optical device with improved cooling performance.