JP3772908B2 - Projection display - Google Patents

Description

    The present invention relates to a projection display device such as a liquid crystal projector.

The liquid crystal projector includes a light source supported by the reflector and a light valve including a liquid crystal panel that modulates illumination light from the light source based on an input video signal. Through the screen.
In such a liquid crystal projector, it is necessary to cool various optical components, such as a light valve and a polarizing plate, which are heated at the time of driving, with cooling air to keep them below the guaranteed temperature limit. In addition, it is necessary to discharge the heat generated from the light source and the power source to the outside of the apparatus to prevent the temperature of the apparatus from rising.
On the other hand, in a liquid crystal projector, for example, when a sirocco fan or an axial fan is used, noise is generated from the fan. It is necessary to suppress this noise as much as possible.
Conventionally, various techniques for achieving both efficient cooling of the apparatus and noise suppression have been proposed (see Patent Document 1).
JP 2001-51349 A

  By the way, an exhaust port (exhaust louver) for exhausting air in the housing of the liquid crystal projector is often provided on a side surface of the housing. When an exhaust louver is provided on the side of the housing, noise generated in the housing is likely to diffuse through the exhaust louver. In addition, the exhaust louver becomes a blowing resistance, which may increase the noise level.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a projection display device that is efficiently cooled and greatly quieted.

A projection display device according to the present invention includes a light source, an optical system that modulates illumination light output from the light source based on input video information, and projects it as an image according to the video information, and at least the light source. A power supply unit that supplies electric power to be driven; a housing that houses the optical system, the light source, and the power supply unit; an exhaust unit that discharges air inside the housing using an axial fan; and at least the housing A cover member that covers the entire top surface, and the exhaust port of the exhaust means is disposed only on the bottom side of the housing, and the cover member is a component formed on the top surface of the housing. Cover at least one opening for attachment and detachment.
Preferably, the cover member further includes a front surface portion covering the front surface of the housing, and a projection port for projecting the image is formed on the front surface portion.

  Preferably, the exhaust means includes a light source exhaust means for generating an air flow for discharging heat from the light source to the outside, and a power supply exhaust means for generating an air flow for discharging heat from the power supply section to the outside. The air flow paths generated by the light source exhaust means and the power source exhaust means are separated from each other.

  Preferably, the housing further includes a support base that supports the housing, the housing is supported by the support base, and has a projecting portion that projects downward, and the exhaust port of the light source exhaust means has the projecting portion. It is formed in a portion, and air is discharged toward the side from between the support base and the housing.

  Preferably, the light source exhaust means is disposed in series with an air inlet formed in the vicinity of the light source at the bottom of the housing and an exhaust port disposed on the bottom of the housing, and sends out air. A plurality of axial fans, and an exhaust duct that is introduced from the intake port, passes through the light source, and guides an air flow sent by the axial fan to the exhaust port.

  Preferably, the exhaust duct includes a plurality of guide plates that equalize an exhaust amount distribution at the exhaust port.

  Preferably, the sirocco fan further includes a sirocco fan that sucks air from the outside of the housing and discharges the air toward an optical component that rises in temperature due to absorption of illumination light of the optical system. An air inlet for is formed.

  Preferably, the sirocco fan is disposed at a position where the cooling air discharged from the sirocco fan joins the air flow generated by the power source exhaust means after cooling the optical component.

In the present invention, at least the upper surface of the casing is entirely covered with the cover member, and the exhaust port of the exhaust means using the axial fan is disposed only on the lower side of the casing. This cover member acts as a soundproof wall that blocks the noise of the axial fan generated in the housing. Further, since the exhaust port through which noise leaks is arranged only on the bottom side of the housing, the noise generated in the housing is not easily transmitted directly to the user.
According to the present invention, it is possible to obtain a projection-type display device that can be efficiently cooled and is largely quieted.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a perspective view of a liquid crystal projector according to an embodiment of the projection display apparatus of the present invention. FIG. 2 is a side view of the liquid crystal projector shown in FIG.
As shown in FIGS. 1 and 2, the liquid crystal projector 1 includes a housing 5, a cover member 6, and a support base 7. The housing 5 includes an upper housing 5A and a lower housing 5B.
As can be seen from FIG. 2, the lower housing 5B includes a protruding portion that protrudes downward from the lower end of the upper housing 5A, and the support base 7 supports the protruding portion.
Various components are housed in a closed space formed between the upper housing 5A and the lower housing 5B.

An intake port 5Ah is formed on one side surface of the upper housing 5A.
Further, a cover member 6 is provided in the upper housing 5A. The cover member 6 has an upper surface portion 6a that covers the entire upper surface of the upper housing 5A and a front surface portion 6b that covers the front surface of the upper housing 5A.
A projection port 6 h for projecting an image is formed on the front surface portion 6 b of the cover member 6.

FIG. 3 is a perspective view showing a state in which the cover member 6 is removed from the upper housing 5A.
As shown in FIG. 3, the cover member 6 can be detached from the upper housing 5A. An upper surface 5At of the upper housing 5A is formed with an opening 5Aa for attaching / detaching a light source described later and an opening 5Ab for attaching / detaching an air filter described later.
The cover member 6 covers these openings 5Aa and 5Ab, and normally the openings 5Aa and 5Ab are not visible from the outside.

In FIG. 2, an exhaust port 5Bh1 is formed on the side surface 5Bf on the front side of the protruding portion of the lower housing 5B. The exhaust port 5Bh1 discharges air exhausted from the inside of the casing 5 to the side, that is, in a horizontal direction along a region sandwiched between the support base 7 and the upper casing 5A.
The bottom of the lower housing 5 </ b> B includes a spherical portion 5 </ b> Bs supported by the support base 7.
As shown in FIG. 4, the attitude of the housing 5 can be adjusted by moving the spherical surface portion 5 </ b> Bs on the support base 7. The elevation angle θ of the projection is adjusted by changing the posture of the housing 5. The elevation angle θ is an angle with respect to the horizontal plane in the projection direction.

FIG. 5 is a perspective view showing an internal configuration of the liquid crystal projector 1. In FIG. 5, the cover member 6 is omitted, and the upper housing 5A and the lower housing 5B are indicated by phantom lines.
As shown in FIG. 5, the liquid crystal projector 1 includes an optical unit case 20, a light source unit 36, an axial fan 50 for power source heat exhaust, axial flow fans 51 and 51 for light source heat exhaust, and an exhaust duct 52. A power source 61, a light source power source 62, an air filter 9, and a sirocco fan 40.

The optical unit case 20 is formed of, for example, aluminum die casting, and an optical unit constituted by each optical component is accommodated in the optical unit case 20.
Here, FIG. 6 is a diagram showing a schematic configuration in the optical unit case 20.
As shown in FIG. 6, the optical unit case 20 includes a total reflection mirror 21, fly-eye lenses 22 and 23, a PS conversion element 24, a condenser lens 25, dichroic mirrors 26 and 28, a relay lens 30, a reflection mirror 27, 29, 30, field lenses 31R, 31G, 31B, incident side polarizing plates 32R, 32G, 32B, liquid crystal panels 33R, 33G, 33B, outgoing side polarizing plates 34R, 34G, 34B, and a cross prism 35 are provided.

  The fly-eye lenses 22 and 23 divide illumination light emitted from a light source unit 36, which will be described later, having a specific distribution in intensity into a number of spots, and uniformly distribute the luminance distribution of the entire screen of the liquid crystal panels 33R, 33G, and 33B. And is arranged apart from the light source.

The PS conversion element 24 and the condenser lens 25 are disposed close to the fly-eye lens 23.
The PS conversion element 24 includes a polarizing beam splitter arranged in a strip shape and a phase difference plate provided intermittently corresponding thereto. The PS conversion element 24 converts the polarization direction of incident light.

The incident-side polarizing plates 32R, 32G, and 32B are disposed on the emission side of the field lenses 31R, 31G, and 31B, respectively. The incident side polarizing plates 32R, 32G, and 32B allow only light having a specific polarization direction to pass therethrough.
Liquid crystal panels 33R, 33G, and 33B as light modulation elements are arranged to face the incident-side polarizing plates 32R, 32G, and 32B, respectively. The liquid crystal panels 33R, 33G, and 33B are arranged so as to face the incident surfaces of the cross prism 35, respectively.

The exit-side polarizing plates 34R, 34G, and 34B are disposed between the incident surfaces of the cross prism 35 and the liquid crystal panels 33R, 33G, and 33B. The exit-side polarizing plates 34R, 34G, and 34B allow only light having a specific polarization direction to pass therethrough.
The cross prism 35 combines the modulated light incident on the respective incident surfaces and outputs the combined light to the projection lens 46.

The light source unit 36 is disposed on the incident side of the total reflection mirror 21. As shown in FIG. 5, the light source unit 36 is assembled as an integrated unit with a light source (not shown) attached to the reflector 37. The light source unit 36 is configured to be detachable through the opening 5Aa of the upper housing 5A shown in FIG.
As the light source of the light source unit 36, for example, a discharge lamp is used. The light source unit 36 generates heat and becomes high temperature. For this reason, it is necessary to discharge the heat generated from the light source unit 36 to the outside.

The illumination light emitted from the light source 36 passes through the total reflection mirror 21, is divided into a large number of spots by the fly-eye lenses 22 and 23, and enters the PS conversion element 24. In the PS conversion element 24, the polarization direction of the light is aligned, and enters the dichroic mirror 26 through the condenser lens 25.
The dichroic mirrors 26 and 28 divide the illumination light into three primary colors of R, G, and B, and enter the field lenses 31R, 31G, and 31B, respectively.
Of the light in each wavelength band, the light having a predetermined polarization direction transmitted through the incident-side polarizing plates 32R, 32G, and 32B is polarized on the liquid crystal panels 33R, 33G, and 33B based on the applied video signals. Is rotated.
Predetermined polarization components of the light whose polarization plane has been rotated are transmitted through the exit-side polarizing plates 34R, 34G, and 34B, are incident on the cross prism 35 as image light, and are color-synthesized.
The color-synthesized light is emitted from the projection lens 46, and a full-color image is projected on a screen (not shown).

  In FIG. 5, the air filter 9 is disposed on the upper part of the sirocco fan 40. The air filter 9 is provided to prevent fine dust from entering the housing 5 from the outside due to the intake air of the sirocco fan 40. Intake of the air filter 9 is performed through an intake port 5Ah formed on the side surface of the upper housing 5. Further, the air filter 9 is detachable through the opening 5Ab of the upper housing 5A shown in FIG.

The sirocco fan 40 is disposed adjacent to the optical unit case 20 and is provided for sucking air through the air filter 9 and applying cooling air to specific optical components of the optical unit case 20.
Among the optical components of the optical unit case 20, the liquid crystal panels 33R, 33G, 33B, the incident side polarizing plates 32R, 32G, 32B, the outgoing side polarizing plates 34R, 34G, 34B, the PS conversion element 24, and the like are illumination light from the light source. Absorbs the temperature rises. Therefore, it is necessary to take air from the outside of the liquid crystal projector 1 into the housing 5 and cool these optical components. In addition, since these optical parts have different temperatures depending on the wavelengths of light of R (red), G (green), and B (blue), it is necessary to cool them with an appropriate air volume according to R, G, and B. is there.

FIG. 7 is an exploded perspective view showing the positional relationship among the optical unit case 20, the sirocco fan 40 and the light source unit 36.
As shown in FIG. 7, a blower duct 41 and a blower distribution sheet 43 are provided between the sirocco fan 40 and the optical unit case 20.

The air duct 41 is fixed to one side surface of the region where the cross prism 35 of the optical unit case 20 is disposed via the air distribution sheet 43.
The main body portion 41a of the blower duct 41 is provided with an intake port 41h, and the discharge port 40a of the sirocco fan 40 is disposed in the intake port 41h.
The branch portion 41b of the air duct 41 is connected to an opening 42P formed on the side surface of the region where the PS conversion element 24 of the optical unit case 20 is disposed.

Openings 42R, 42G, and 42B are formed on the side surface of the optical unit case 20 that faces the air duct 41.
In the air distribution sheet 43, openings 43R, 43G, and 43B corresponding to the openings 42R, 42G, and 42B are formed. The areas of the openings 43R, 43G, and 43B of the air distribution sheet 43 are different so that the necessary air volume is blown to the optical components according to R, G, and B, respectively.

When cooling air is supplied from the discharge part 40a of the sirocco fan 40 to the air duct 41, this cooling air is supplied into the optical unit case 20 through the openings 42R, 42G, and 42B and the opening 42P, and crosses the optical unit case 20. To do. Then, the optical unit case 20 is discharged from an opening (not shown) formed on the other side surface.
When the cooling air supplied from the sirocco fan 40 traverses the optical unit case 20, the liquid crystal panels 33R, 33G, 33B, the incident side polarizing plates 32R, 32G, 32B, the outgoing side polarizing plates 34R, 34G, 34B and PS The conversion element 24 and the like are cooled.

In FIG. 5, a power supply unit 61 and a light source power supply unit 62 are composed of a printed wiring board, an electronic component, etc., and the power supply unit 61 and the light source power supply unit 62 constitute a power supply unit of the present invention.
The power supply unit 61 supplies power for driving the liquid crystal panels 33R, 33G, and 33B, the sirocco fan 40, the axial fans 50 and 51, and the like.
The light source power supply unit 62 supplies power for driving the light source of the light source unit 36. A plate member 63 is provided above the power supply unit 61 and the light source power supply unit 62. The plate member 63 is provided to form an air flow path.
In addition, since the power supply unit 61 and the light source power supply unit 62 release heat by supplying power, it is necessary to discharge the heat from the power supply unit 61 and the light source power supply unit 62 to the outside.

  The axial fan 50 is installed on the side of the power supply unit 61 and the light source power supply unit 62. The axial fan 50 mainly sucks the air on the power source unit 61 and the light source power source unit 62 side and sends it out toward the air blowing guide 55. As shown in FIG. 5, an exhaust port 5 </ b> Bh <b> 2 is formed at a position where the air guide 55 of the lower housing 5 </ b> B is provided. The air sent out by the axial fan 50 is bent in the blowing direction by the blowing guide 55 and is discharged downward from the exhaust port 5Bh2.

The axial fan 51 is disposed in front of the light source unit 36 as shown in FIG.
Two axial fans 51 are arranged in series. By arranging two in series, it is possible to obtain an exhaust air volume and a static pressure that cannot be achieved by a normal axial fan having the same size. Conversely, the fan drive voltage required to obtain the required exhaust air volume and static pressure can be reduced, and the noise generated by the axial fan 51 can be suppressed.

The exhaust duct 52 is provided on the exhaust side of the axial flow fan 51. The exhaust duct 52 guides the air flow sent from the axial fan 51 to the exhaust port 5Bh1 formed in the lower housing 5B.
Here, FIG. 8 is a perspective view showing the structure of the exhaust duct 52.
In FIG. 8, the exhaust duct 52 has a duct body 55 and a cover member 53, and an exhaust path is formed by the duct body 55 and the cover member 53. In practice, the cover member 53 is fixed on the duct body 55.

A plurality of guide plates 54 are formed in the exhaust passage by the duct body 55 and the cover member 53.
The plurality of guide plates 54 act so that the air flow sent from the axial fan 51 flows evenly in the exhaust passage, and an even exhaust amount distribution is obtained at the exhaust port 5Bh1. The air flow sent from the axial fan 51 becomes high temperature, and if it is concentrated locally at the exhaust port 5Bh1, a high temperature region is partially generated, which is not preferable. By providing a plurality of guide plates 54 and evenly dispersing the high-temperature air flow at the exhaust port 5Bh1, it is possible to prevent the generation of a partially high-temperature region.

Next, the exhaust operation by the axial fans 50 and 51 in the liquid crystal projector 1 having the above configuration will be described with reference to FIGS.
FIG. 9 is a diagram illustrating an exhaust operation by the axial fan for light source heat exhaust.
As shown in FIG. 9, an intake port 5BP1 is formed on the rear end side where the light source unit 36 of the lower housing 5B is installed. The intake port 5BP1, the axial flow fan 51, the exhaust duct 52, and the exhaust port 5Bh1 constitute a light source exhaust unit that generates an air flow that exhausts heat from the light source of the present invention to the outside.

When the axial fan 51 is driven, outside air is sucked from the intake port 5BP1, passes through the light source unit 36, and is discharged to the outside through the exhaust duct 52 from the exhaust port 5Bh1. Thereby, the heat generated in the light source unit 36 is discharged to the outside.
At this time, the exhaust port 5Bh1 is formed on the side surface 5Bf on the front surface side of the protruding portion of the lower housing 5B, and hot air is sandwiched between the support 5 and the upper housing 5A from within the housing 5. Exhale horizontally along the area. For this reason, the high temperature air discharged | emitted by the table etc. which mounts the support stand 7, the housing | casing 5, or the support stand 7 does not hit directly, and these can be prevented from being heated with high temperature air. .

FIG. 10 is a diagram showing an exhaust operation by the axial flow fan 50 for power source heat exhaust.
As shown in FIG. 10, an intake port 5BP2 is formed on the rear end side of the lower housing 5B where the power supply unit 62 is installed. The intake port 5BP2, the plate member 63, the axial fan 50, the air blowing guide 55, and the exhaust port 5Bh2 constitute a power source exhaust unit that generates an air flow that exhausts heat from the power source unit of the present invention to the outside.

  When the axial fan 50 is driven, outside air is sucked from the intake port 5BP2, passes through the power source 62, and is discharged to the outside from the exhaust port 5Bh1. Thereby, the heat generated in the power supply unit 62 is discharged to the outside.

Here, the air flow generated by the axial fan 51 is AF1, the air flow generated by the axial fan 50 is AF2, and the air flow generated by the sirocco fan 40 is AF3. As shown in FIG. 5, the paths of the air flow AF1 by the axial fan 51 and the air flow AF2 by the axial fan 50 are separated from each other. For this reason, the heat generated in the power supply units 61 and 62 and the heat generated in the light source unit 36 can be efficiently discharged to the outside, and the heat is not easily trapped inside the housing 5.
Further, as shown in FIG. 5, the air flow AF3 by the sirocco fan 40 cools the optical unit, and then merges with the air flow AF2 by the axial fan 50, and is discharged to the outside through the exhaust port 5Bh2. For this reason, the air flow AF3 generated by the sirocco fan 40 cools the optical unit, so that the air whose temperature has increased is less likely to stay in the housing 5.

Moreover, in this embodiment, the capacity | capacitance of the axial fans 50 and 51 can be made small by isolate | separating the exhaust heat of the power supply parts 61 and 62 and the exhaust heat of the light source unit 36. FIG. For this reason, the noise generated from the axial fans 50 and 51 can be reduced.
Further, in the present embodiment, the intake into the housing 5 is limited to the intake ports 5BP1, 5BP2, and 5Ah, and the exhaust air volume is improved by separating into the axial fan 50 and the axial fan 51, thereby 5 The inside is lower than atmospheric pressure. As a result, sufficient outside air is always supplied to the inside of the housing 5 and the rise in the in-machine temperature is reliably suppressed.
Furthermore, the heat generated from the light source disposed inside the housing 5 is discharged by arranging a plurality of axial fans 51 in series, so that efficient heat removal can be performed while reducing noise. it can.

In addition, according to the present embodiment, the cover member 6 covers the entire upper surface and front surface of the housing 5 to prevent the noise generated from the axial fans 50 and 51 and the sirocco fan 40 from diffusing. The liquid crystal projector 1 can be quieted.
Further, according to the present embodiment, by not providing an opening for heat exhausting in the upper housing 5A, a new design is possible and differentiation with rich novelty is possible.

  It should be noted that the specific shapes and structures of the respective parts shown in the above-described embodiments are merely examples for implementation in carrying out the present invention, and the technical scope of the present invention is thereby limited. It is not intended to be interpreted.

It is a perspective view of the liquid crystal projector which concerns on one Embodiment of the projection type display apparatus of this invention. FIG. 2 is a side view of the liquid crystal projector shown in FIG. 1. It is a perspective view which shows the state which removed the cover member from the upper side housing | casing. It is a figure which shows the state which adjusted the elevation angle of the liquid crystal projector. It is a perspective view which shows the internal structure of a liquid crystal projector. It is a figure which shows schematic structure in an optical unit case. It is a disassembled perspective view which shows the positional relationship of an optical unit case, a sirocco fan, and a light source unit. It is a perspective view which shows the structure of an exhaust duct. It is a figure which shows the exhaust operation by the axial flow fan for light source thermal exhaust. It is a figure which shows the exhaust operation by the axial flow fan for power source heat exhaust.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Liquid crystal projector, 5 ... Housing, 5A ... Upper housing, 5B ... Lower housing, 6 ... Cover member, 7 ... Turntable, 9 ... Air filter, 20 ... Optical unit case, 32 ... Incident side polarizing plate 33 ... Liquid crystal panel, 34 ... Emission side polarizing plate, 35 ... Cross prism, 36 ... Light source unit, 40 ... Sirocco fan, 55 ... Air duct, 43 ... Air distribution sheet, 50, 51 ... Axial fan.

Claims (8)

A light source;
An optical system that modulates illumination light output from the light source and projects the image according to the video information based on the input video information;
A power supply that supplies at least power for driving the light source;
A housing that houses the optical system, the light source, and the power supply unit;
Exhaust means for exhausting the air in the housing to the outside using an axial fan;
A cover member that entirely covers at least the upper surface of the housing;
The exhaust port of the exhaust means is disposed only on the bottom side of the housing,
The said cover member is a projection type display apparatus which covers the at least 1 opening for attaching or detaching a component formed in the upper surface of the said housing. The cover member further has a front surface portion that covers the front surface of the housing, and a projection port that projects the image is formed on the front surface portion.
The projection display device according to claim 1. The exhaust means includes a light source exhaust means for generating an air flow for exhausting heat from the light source to the outside;
Power supply exhaust means for generating an air flow for discharging heat from the power supply unit to the outside,
The projection display device according to claim 1, wherein paths of airflows generated by the light source exhaust unit and the power source exhaust unit are separated from each other. A support base for supporting the housing;
The housing is supported by the support base and has a protruding portion protruding downward,
The projection display device according to claim 3 , wherein an exhaust port of the light source exhaust unit is formed in the projecting portion, and exhausts air from between the support base and the housing toward a side. The light source exhaust means includes an air inlet formed in the vicinity of the light source at the bottom of the housing;
An exhaust port disposed on the bottom side of the housing;
A plurality of axial fans arranged in series and delivering air;
The projection display device according to claim 3 , further comprising: an exhaust duct that is introduced from the intake port, passes through the light source, and guides an air flow sent out by the axial fan to the exhaust port. The projection display device according to claim 5 , wherein the exhaust duct includes a plurality of guide plates that equalize an exhaust amount distribution at the exhaust port. A sirocco fan that sucks air from the outside of the housing and discharges it toward an optical component that rises in temperature due to absorption of illumination light of the optical system,
2. The projection display device according to claim 1, wherein an air inlet for the sirocco fan is formed on one side surface of the housing. The projection type according to claim 7 , wherein the sirocco fan is disposed at a position where the cooling air discharged from the sirocco fan cools the optical component and then merges with the air flow generated by the power supply exhaust unit. Display device.

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