JP2011209532A - Projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projector for effectively cooling optical modulators.SOLUTION: The projector 1 includes: a plurality of optical modulators 351 which modulate a plurality of color light beams, according to image information; a cooling device 4 for cooling the optical modulators 351. The cooling device 4 includes: a first cooling fan 5 which sucks and discharges air; a duct 6 for distributing air discharged from the first cooling fan 5 sequentially from the side to at least two optical modulators 351; and a second cooling fan 7 sucking air in the duct 6.

Description

  The present invention relates to a projector.

Conventionally, three light modulation devices such as a liquid crystal panel that modulates three color lights of R (red), G (green), and B (blue) according to image information, and a cooling device that cools these light modulation devices A projector provided is known (see, for example, Patent Document 1).
The projector described in Patent Document 1 employs a cooling device described below in order to reduce the thickness dimension of the projector.
That is, the cooling device includes a sirocco fan disposed on the side of the projection lens and a duct (flow path) that guides air discharged from the sirocco fan to each light modulation device.
The duct is configured in a U-shape that surrounds three light incident side end faces in a cross-sectional view of a cross dichroic prism that synthesizes each color light modulated by each light modulation device.
And the air discharged from the sirocco fan distribute | circulates the inside of a duct, distribute | circulates in the order adjacent from the side of an optical modulator, and cools three optical modulators.

JP 2001-281613 A

  However, in the cooling device described in Patent Document 1, since the duct is bent and the light modulation device is disposed inside the duct, the flow passage area is also reduced, so the pressure loss in the duct is large. It has a structure. That is, since the static pressure inside the duct is high, there is a problem that the air volume discharged from the sirocco fan into the duct cannot be sufficiently secured and the light modulation device cannot be cooled effectively. .

  An object of the present invention is to provide a projector capable of effectively cooling a light modulation device.

  The projector of the present invention is a projector including a plurality of light modulation devices that respectively modulate a plurality of color lights according to image information, and a cooling device that cools the light modulation device. A first cooling fan that sucks and discharges; a duct that distributes air discharged from the first cooling fan to at least two light modulation devices in order from the side; and a duct that sucks air inside the duct And a second cooling fan that discharges to the outside.

In the present invention, the cooling device includes the first cooling fan and the duct described above, and a second cooling fan that sucks air inside the duct and discharges the air outside the duct.
Thus, the static pressure inside the duct can be reduced by sucking the air inside the duct with the second cooling fan. For this reason, the air volume discharged from the first cooling fan into the duct can be sufficiently secured, and at least two light modulation devices can be effectively cooled by the air flowing through the duct.

In the projector according to the aspect of the invention, in the first cooling fan and the second cooling fan, the air volume discharged by the first cooling fan is larger than the air volume sucked by the second cooling fan. It is preferable that it is comprised.
In the present invention, since the first cooling fan and the second cooling fan are configured as described above, the inside of the duct can be at a high pressure. For this reason, for example, even when another heat generating member is disposed close to the duct, air heated by the heat generating member does not flow into the duct from the gap. Therefore, the temperature inside the duct is not increased by other heat generating members, and the light modulation device can be cooled more effectively.

In the projector according to the aspect of the invention, it is preferable that a communication hole for discharging the internal air to the outside is formed in the duct.
By the way, when the 1st cooling fan and the 2nd cooling fan are constituted as mentioned above, since the air volume introduced into the duct is larger than the air volume discharged outside the duct, the internal pressure of the duct tends to be high.
According to the present invention, even if the first cooling fan and the second cooling fan are configured as described above, the second cooling fan out of the air volume introduced into the duct by the first cooling fan. The air volume that cannot be exhausted outside the duct can be exhausted outside the duct through the communication hole formed in the duct. For this reason, it can suppress that the internal pressure of a duct becomes high, and can fully ensure the air volume of the air ventilated by at least 2 light modulation apparatus.

In the projector according to the aspect of the invention, the duct may include a first duct that allows air discharged from the first cooling fan to flow to the at least two light modulation devices in order from the side, and an air flow path downstream of the first duct. And a second duct that guides the air after flowing through the first duct to the second cooling fan, and the communication hole is preferably formed in the second duct.
By the way, when the communication hole described above is formed in the first duct, the air inside the first duct is discharged to the outside through the communication hole, so the air volume of the air blown to at least two light modulation devices Will fall.
In the present invention, since the communication hole is formed in the second duct, the air after flowing through the first duct is discharged to the outside of the duct through the communication hole, and is blown to at least two light modulation devices. Sufficient air volume can be secured.

FIG. 2 is a plan view schematically showing the internal configuration of the projector in the first embodiment. The figure which shows typically the structure of the cooling device in 1st Embodiment. The figure which shows typically the structure of the cooling device in 1st Embodiment. The figure which shows an example of the PQ characteristic of each cooling fan in 1st Embodiment. The figure which shows typically the structure of the cooling device in 2nd Embodiment. It is a figure for demonstrating the effect of 2nd Embodiment.

[First embodiment]
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a first embodiment of the invention will be described with reference to the drawings.
[Configuration of projector]
FIG. 1 is a plan view schematically showing the internal configuration of the projector 1.
In the following, for convenience of explanation, a side on which a projection lens 36 to be described later is disposed is referred to as “front surface”, and the opposite side is referred to as “back surface”.
The projector 1 displays a projection image on a screen (not shown). As shown in FIG. 1, the projector 1 includes an exterior casing 2 that constitutes an exterior, an optical unit 3 and a cooling device 4 (in FIG. 1, some constituent members (cooling members)). Only the fans 5 and 7) are shown.

[Configuration of exterior casing]
As shown in FIG. 1, the exterior housing 2 includes a top surface portion (not shown) and a bottom surface portion 21 that intersect the vertical axis, and side surface portions 22 to 25 (hereinafter referred to as front surface side portions) that connect the top surface portion and the bottom surface portion 21. The side part includes a front part 22 and the back side part includes a back part 23), and has a substantially rectangular parallelepiped shape.

[Configuration of optical unit]
As shown in FIG. 1, the optical unit 3 has a substantially L-shape in plan view that extends along the back surface portion 23 and has one end side extending toward the front surface portion 22.
As shown in FIG. 1, the optical unit 3 includes a light source device 31 having a light source lamp 311 and a reflector 312, an illumination optical device 32 having lens arrays 321, 322, a polarization conversion element 323, and a superimposing lens 324, and a dichroic. A color separation optical device 33 having mirrors 331 and 332 and a reflection mirror 333, an incident side lens 341, a relay lens 343, a relay optical device 34 having reflection mirrors 342 and 344, and three liquid crystal panels as light modulation devices 351, three incident side polarizing plates 352, three outgoing side polarizing plates 353, an optical device 35 having a cross dichroic prism 354 as a color synthesizing optical device, a projection lens 36 as a projection optical device, and each of these members 31 ~ 35 are accommodated inside and the projection lens 36 is supported. And an optical component housing 37.

In the optical unit 3, the light beam emitted from the light source device 31 and passing through the illumination optical device 32 is separated into three color lights of R, G, and B by the color separation optical device 33 with the above-described configuration. Each separated color light is modulated by each liquid crystal panel 351 in accordance with image information. The modulated color lights are combined by a prism 354 to form an image and projected onto a screen by a projection lens 36.
In FIG. 1, for convenience of explanation, the liquid crystal panel 351 on the R color light side, the incident side polarizing plate 352, and the output side polarizing plate 353 are referred to as an R side member 350R, and the G color light side and the B color light side are similarly G side members. 350G and B-side member 350B. The same applies to the subsequent figures.

[Configuration of cooling device]
2 and 3 are diagrams schematically showing the configuration of the cooling device 4. Specifically, FIG. 2 is a perspective view of the cooling device 4 as viewed from the upper rear side, and FIG. 3 is a view in which the lid 62 of the duct 6 is removed in FIG.
As shown in FIG. 1, the cooling device 4 is provided close to the projection lens 36, and cools the optical device 35 by sending air to the optical device 35. As shown in FIGS. 1 to 3, the cooling device 4 includes a first cooling fan 5, a duct 6 (FIGS. 2 and 3), and a second cooling fan 7.
The first cooling fan 5 is a so-called sirocco fan having a plurality of blades bent forward with respect to the fan rotation direction, and is disposed on the right side when viewed from the front side with respect to the projection lens 36. .
More specifically, as shown in FIG. 2 or FIG. 3, the first cooling fan 5 has a suction port 51 that sucks air and faces the upper side (the top surface side of the exterior housing 2) and discharges air. The outlet 52 is disposed so as to face obliquely left rearward (front side of the B-side member 350B) when viewed from the front side.

The duct 6 allows the air discharged from the first cooling fan 5 to flow in the order of the B-side member 350B, the G-side member 350G, and the R-side member 350R. As shown in FIG. 2 or 3, the duct 6 includes a duct body 61 and a lid 62 (FIG. 2).
As shown in FIG. 2 or FIG. 3, the duct main body 61 includes an introduction side duct portion 611, a main body portion 612, and a discharge side duct portion 613.
The introduction-side duct portion 611 has a cylindrical shape, and one end (an introduction port for introducing air into the duct 6) is connected to the discharge port 52 of the first cooling fan 5 as shown in FIG. 2 or FIG. And, it is formed so as to extend along the discharge direction of the air from the discharge port 52. The introduction-side duct portion 611 is connected to the main body portion 612 at the other end and communicates with the inside of the main body portion 612.

As shown in FIG. 2 or 3, the main body 612 is formed in a container shape having an inner peripheral wall 612A (FIG. 3), an outer peripheral wall 612B, and a bottom wall 612C (FIG. 3).
The inner peripheral wall 612A has a substantially U shape in plan view surrounding the incident side end surfaces 354R, 354G, and 354B (FIGS. 1 and 3) on which light of each color of R, G, and B in the prism 354 is incident.
Although not specifically shown, the inner peripheral wall 612A is formed with three openings for allowing the R, G, and B color lights to enter the prism 354 via the members 350R, 350G, and 350B. ing.
Then, as shown in FIG. 3, a liquid crystal panel 351 and an emission-side polarizing plate 353 are attached to the inner peripheral wall 612A via support members 355 so as to face the incident-side end surfaces 354R, 354G, and 354B, respectively. .

Further, the front side ends of the inner peripheral wall 612A are connected by a connection wall 612D (FIG. 3) so as to cover the emission side end surface 354E (FIGS. 1 and 3) from which the synthesized image of the prism 354 is emitted. ing.
Although not specifically shown, an opening for allowing the image synthesized by the prism 354 to pass therethrough is formed in the connection wall 612D.
The connection wall 612D has a function of allowing only the image synthesized by the prism 354 to pass through the opening and blocking unnecessary light (leakage light) from entering the projection lens 36.

The outer peripheral wall 612B is positioned on each of the R, G, and B incident sides with respect to the inner peripheral wall 612A, and has a substantially U shape in plan view that is substantially parallel to the inner peripheral wall 612A.
Although not specifically shown, the outer peripheral wall 612B is formed with three openings for allowing the R, G, and B color lights to pass through the respective incident-side polarizing plates 352.
Then, as shown in FIG. 2 or FIG. 3, three incident-side polarizing plates 352 are attached to the outer peripheral wall 612B so as to close the three openings.
The bottom wall 612C connects the ends of the inner peripheral wall 612A and the outer peripheral wall 612B on the bottom surface portion 21 side.

The main body portion 612 is closed at the upper side by the lid body 62, thereby allowing the air discharged from the first cooling fan 5 and flowing through the introduction-side duct portion 611 to flow through a substantially C-shaped channel C (see FIG. 3) It distributes in the horizontal direction along. That is, the main body 612 is arranged in the order of the B-side member 350B, the G-side member 350G, and the R-side member 350R from the side of each member 350R, 350G, 350B along the substantially U-shaped flow path C in plan view. Circulate. The air that follows the flow path C flows through the light incident side and the light emitting side of the liquid crystal panel 351, and cools the members 350R, 350G, and 350B.
The introduction-side duct portion 611, the main body portion 612, and the lid body 62 described above correspond to the first duct 6A (FIGS. 2 and 3) according to the present invention.

As shown in FIG. 2 or FIG. 3, the discharge side duct portion 613 has a cylindrical shape extending from the back side toward the front side.
Then, one end of the discharge side duct portion 613 is connected to the front end portion of the R side member 350 </ b> R in the main body portion 612 and communicates with the inside of the main body portion 612.
The discharge-side duct portion 613 is formed so that the cross-sectional area of the other end is larger than one end, and the other end (the discharge port for discharging the air inside the duct 6 to the outside) is the second cooling fan 7. To the suction port (not shown).
That is, the discharge side duct part 613 is connected to the downstream side of the flow path C of the main body part 612 and guides the air after flowing through the main body part 612 to the second cooling fan 7.
The discharge side duct portion 613 described above corresponds to the second duct according to the present invention.

The second cooling fan 7 is a so-called turbofan having a plurality of blades bent backward with respect to the fan rotation direction, and is disposed on the left side when viewed from the front side with respect to the projection lens 36. .
More specifically, as shown in FIG. 2 or FIG. 3, the second cooling fan 7 has a suction port (not shown) for sucking air directed to the back side and a discharge port 71 for discharging air viewed from the front side. It is arranged to face the left side.
The second cooling fan 7 sucks air inside the main body 612 through the discharge duct portion 613, and the exhaust fan 8 (see FIG. Discharge toward 1).

FIG. 4 is a diagram illustrating an example of PQ characteristics of the cooling fans 5 and 7.
In FIG. 4, the P (static pressure) -Q (air volume) characteristic of the first cooling fan 5 is indicated by a solid line, and the PQ characteristic of the second cooling fan 7 is indicated by a broken line.
In the present embodiment, as shown in the example of FIG. 4, the first cooling fan 5 employs a fan having a higher capacity than the second cooling fan 7 (for example, a fan having a larger size than the second cooling fan 7). ing.
That is, the cooling fans 5 and 7 are configured such that the air volume of air discharged from the first cooling fan 5 is larger than the air volume of air sucked by the second cooling fan 7.

The first embodiment described above has the following effects.
In the present embodiment, the cooling device 4 includes the first cooling fan 5 and the duct 6 described above, and a second cooling fan 7 that sucks air inside the duct 6 and discharges the air inside the duct 6.
Thus, the static pressure inside the duct 6 can be reduced by sucking the air inside the duct 6 by the second cooling fan 7. For this reason, it is possible to secure a sufficient amount of air discharged from the first cooling fan 5 to the inside of the duct 6, and the members 350 </ b> R, 350 </ b> G, 350 </ b> B can be effectively cooled by the air flowing through the inside of the duct 6.
Further, since the static pressure inside the duct 6 can be reduced, a sufficient air volume can be ensured even if a small fan is adopted as the first cooling fan 5. For this reason, by adopting a small fan as the first cooling fan 5, the projector 1 can be miniaturized, and noise during driving can be reduced to ensure quietness of the projector 1.

Furthermore, since the fan with higher capability than the 2nd cooling fan 7 is employ | adopted as the 1st cooling fan 5, the inside of the duct 6 can be made into a high voltage | pressure. For this reason, for example, even when another heat generating member (for example, a power supply device) is disposed in the vicinity of the duct 6, the air heated by the heat generating member remains in the gap (the main body portion 612 and It does not flow into the inside of the duct 6 from a gap between the lids 62). Therefore, the temperature inside the duct 6 is not increased by other heat generating members, and the members 350R, 350G, and 350B can be cooled more effectively.
Further, since it is possible to prevent air from flowing into the duct 6 from the gap, it is possible to prevent dust and the like from adhering to the liquid crystal panels 351 and the like. That is, dust or the like attached to each liquid crystal panel 351 or the like does not appear in the projected image, and the image quality of the projected image can be maintained favorably.

[Second Embodiment]
Next, 2nd Embodiment of this invention is described based on drawing.
In the following description, the same structure and the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted or simplified.
FIG. 5 is a diagram schematically showing the configuration of the cooling device 4 in the second embodiment. Specifically, FIG. 5 is a perspective view of the cooling device 4 as seen from the upper rear side.
The cooling device 4 of this embodiment differs from the first embodiment only in that a communication hole 613A is formed in the discharge-side duct portion 613 as shown in FIG.
As shown in FIG. 5, the communication hole 613 </ b> A is formed on the left side surface when viewed from the front surface side in the discharge-side duct portion 613.

The second embodiment described above has the following effects in addition to the same effects as those of the first embodiment.
FIG. 6 is a diagram for explaining the effect of the second embodiment. Specifically, FIG. 6 is a diagram showing the relationship between the internal pressure of the duct 6 and the opening area of the communication hole 613A.
In FIG. 6, the internal pressure of the duct 6 is indicated by a solid line, and the external pressure (atmospheric pressure) of the duct 6 is indicated by a broken line. In FIG. 6, the opening area of the communication hole 613A shown on the horizontal axis is such that the opening area increases toward the right side in FIG.
In the present embodiment, even if a fan having a higher capacity than the second cooling fan 7 is adopted as the first cooling fan 5, the first cooling fan 5 out of the air volume introduced into the duct 6 is the first air volume. The amount of air that cannot be exhausted to the outside of the duct 6 by the two cooling fans 7 can be exhausted to the outside of the duct 6 through the communication hole 613 </ b> A formed in the duct 6. For this reason, it can suppress that the internal pressure of the duct 6 becomes high, and can fully ensure the air volume of the air sent by each member 350R, 350G, 350B.

Further, if the opening area of the communication hole 613A is appropriately set, as shown in FIG. 6, the internal pressure of the duct 6 can be sufficiently lowered while the inside of the duct 6 is set to a positive pressure. For this reason, the air outside the duct 6 flows through the gaps (gap between the main body 612 and the lid body 62) and the communication holes 613A while ensuring a sufficient amount of air blown to each member 350R, 350G, 350B. It can be prevented from flowing into the inside.
Further, since the communication hole 613A is formed in the discharge side duct portion 613, the air after flowing through the first duct 6A is discharged to the outside of the duct 6 through the communication hole 613A, and each member 350R, 350G , 350B does not decrease the air volume of the air blown.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
In each of the above-described embodiments, the sirocco fan and the turbo fan are employed as the cooling fans 5 and 7, but the present invention is not limited thereto, and in addition to the sirocco fan and the turbo fan, air is sucked and discharged along the fan rotation axis. An axial fan that does this may be adopted.
In each of the above-described embodiments, the duct 6 is configured to circulate air through the members 350R, 350G, and 350B. For example, the duct 6 has a substantially L shape in plan view that circulates air only through the members 350G and 350B. You may comprise.
In each of the above embodiments, when air is circulated through the members 350R, 350G, and 350B, the air is circulated in the order of the B-side member 350B, the G-side member 350G, and the R-side member 350R. For example, the arrangement positions of the members 350R, 350G, and 350B may be changed, and air may be circulated in the order of the G-side member 350G, the B-side member 350B, and the R-side member 350R.

In each of the above embodiments, the cross dichroic prism 354 is employed as a configuration for combining the R, G, and B color lights emitted from the respective members 350R, 350G, and 350B. However, the configuration is not limited thereto, and a plurality of dichroic mirrors are used. It does not matter as a configuration using
In each of the above embodiments, the projector 1 is configured to include the three liquid crystal panels 351, but the present invention is not limited to this. That is, the present invention can also be applied to a projector using two or four or more liquid crystal panels.
In each of the above embodiments, as the light modulation device, a reflective liquid crystal panel may be adopted in addition to a transmissive liquid crystal panel.
In the above embodiment, only an example of a front projection type projector has been described. However, the present invention can also be applied to a rear type projector that includes a screen and performs projection from the back side of the screen.

  The present invention can be used for projectors used in presentations, home theaters, and the like.

  DESCRIPTION OF SYMBOLS 1 ... Projector, 4 ... Cooling device, 5 ... 1st cooling fan, 6 ... Duct, 6A ... 1st duct, 7 ... 2nd cooling fan, 351 ... Liquid crystal Panel (light modulation device), 613... Discharge side duct (second duct), 613A.

Claims (4)

A projector comprising a plurality of light modulation devices that respectively modulate a plurality of color lights according to image information, and a cooling device that cools the light modulation device,
The cooling device is
A first cooling fan that sucks and discharges air;
A duct for circulating air discharged from the first cooling fan in order from the side to the at least two light modulation devices;
A projector comprising: a second cooling fan that sucks air inside the duct and discharges the air outside the duct. The projector according to claim 1.
The first cooling fan and the second cooling fan are:
The projector is configured such that an air volume of air discharged by the first cooling fan is larger than an air volume of air sucked by the second cooling fan. The projector according to claim 2,
In the duct,
A projector characterized in that a communication hole for discharging the air inside is formed. The projector according to claim 3.
The duct is
A first duct for allowing air discharged from the first cooling fan to flow to the at least two light modulation devices in order from the side;
A second duct that is connected to the downstream side of the air flow path in the first duct and guides the air after flowing through the first duct to the second cooling fan;
The communication hole is
A projector formed in the second duct.

Images