JP2006211388A - Image display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin image display apparatus having high productivity and excellent appearance and capable of providing reverberation with realistic sensations. <P>SOLUTION: A rear projector 1 comprises an image display unit for forming and displaying an image in response to input image information, a voice output unit 7 for outputting a voice in response to input voice information, and a box-shaped casing for accommodating these members. The voice output unit 7 comprises an enclosure 71 formed into a box shape with a frame 22 and a mirror case 21; a loudspeaker 72 mounted on the frame 22 that forms the enclosure 71; a sound issuing hole 73 for high-pitched sounds formed in the frame 22 on which the loudspeaker 72 is mounted; and a duct 74 protruded into the enclosure 71 from the mirror case 21, and having an opening end 741 exposed to the outside in the mirror case 21 that forms the enclosure 71. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image display device that forms and displays an image according to input image information. In particular, the present invention relates to thin image display devices such as liquid crystal televisions and rear projectors.

In recent years, thin image display devices such as liquid crystal televisions and rear projectors are becoming popular. These thin image display devices have advantages such as space saving of an installation place and an excellent appearance.
Conventionally, a rear projector includes an image display unit that forms and displays an image according to input image information, an audio output unit that outputs sound according to audio information input together with the image information, and an image display unit And a box-shaped housing that houses the audio output unit, and an image display unit is exposed on the front surface of the housing (see, for example, Patent Document 1).

The audio output unit is often provided around the image display unit exposed on the front surface of the housing, like the rear projector of Patent Document 1. Conventionally, the audio output unit is formed by penetrating a box-shaped acoustic housing, a speaker attached to the front surface of the acoustic housing in a state in which the acoustic housing is housed, and a front surface of the acoustic housing to which the speaker is attached. It has a sound emission hole.
When the case of the image display device provided with such an audio output unit is formed so that it can be seen as a single substantially plate-like shape from the inspector, the above-mentioned image display device has the space saving and excellent appearance, etc. The advantage can be retained. For this reason, the audio output unit is also required to be thin like the image display device.

Furthermore, in order to provide the observer with a realistic reverberation sound, the sound output unit is required to improve sound quality. A bass-reflex type acoustic casing is known as a configuration of an acoustic casing capable of improving sound quality. The bass-reflex type acoustic housing is provided with a duct that protrudes from the front surface to the inside of the acoustic housing and has an open end exposed outside. Such a bass-reflex type acoustic housing reinforces the sound in the bass region output from the speaker by resonating the sound within the acoustic housing and the duct.
Conventionally, the casing of the image display apparatus is often formed by injection molding of a synthetic resin, and the above-described duct is often integrally molded when the casing is molded.

However, when the acoustic housing is injection-molded together with the duct, the molded product is contracted due to thermal expansion of the synthetic resin at the time of molding and contraction after the molding. In particular, since the effect of this shrinkage is large in the vicinity of the opening end of the duct, a recess that is recessed toward the inside of the acoustic casing is formed on the front surface of the acoustic casing in the vicinity of the opening end of the duct.
As described above, when the dent is formed on the front surface of the acoustic casing near the opening end of the duct, the appearance of the image display device may be impaired. In order to solve such a problem in appearance, a decorative cover that covers the front surface of the acoustic housing may be attached to the image display device.

JP 2003-274314 A

  However, as described above, when the decorative cover is attached to the front surface of the acoustic housing, the number of parts and the manufacturing process increase, and the productivity of the image display device decreases. In addition, the thickness of the acoustic housing by the amount of the decorative cover, that is, the thickness of the image display device provided with the acoustic housing is increased, so that the appearance of the image display device is impaired. However, there is a problem that it is impossible to meet the demand for thinning.

  An object of the present invention is to provide a thin image display device that has high productivity and an excellent appearance and can provide a realistic reverberation sound.

  An image display device according to the present invention includes an image display unit that forms and displays an image according to input image information, an audio output unit that outputs audio according to audio information input together with the image information, and an image An image display device including a box-shaped housing for storing a display unit and an audio output unit, wherein the housing includes a front portion of the housing from which the image display portion is exposed and a rear surface side of the front portion of the housing. The sound output unit is attached to the front part of the housing in a state of being housed in the acoustic case and the acoustic case formed in a box shape by the front part of the case and the rear part of the case. A speaker, a high-frequency sound emission hole formed in the front part of the casing to which the speaker is attached, and a rear part of the casing forming the acoustic casing, project from the rear part of the casing into the acoustic casing. And including a duct with an open end exposed to the outside. And it features.

When the acoustic casing is injection molded together with the duct, the molded product is accompanied by shrinkage of the shape, so the acoustic casing near the opening end of the duct must have a dent that sinks toward the inside of the acoustic casing. There are many.
However, according to the present invention, the duct is formed at the rear part of the casing so as to protrude toward the inside of the acoustic casing. For this reason, a dent near the opening end cannot be seen from an observer viewing the image display device from the front side. As a result, the appearance of the image display device can be improved.
As described above, since the viewer does not see any dents and the appearance of the image display device is good, it is not necessary to attach a decoration cover or the like to the front of the housing. For this reason, the number of parts of the image display device can be suppressed.

Furthermore, as described above, since it is not necessary to attach a cover or the like as a decoration to the surface of the speaker installation portion, the thickness of the audio output portion can be suppressed. That is, the audio output unit can be made as thin as possible. Thus, even if the audio output unit is provided in a thin image display device, advantages such as space saving and an excellent appearance of the thin image display device are not impaired.
According to the acoustic casing having such a configuration, the sound in the low frequency range can be enhanced by resonating the sound emitted from the back portion of the speaker inside the acoustic casing and the duct. As a result, it is possible to provide a realistic sound to the inspector.

  In the image display device of the present invention, the sound emitting hole is formed by penetrating the front part of the casing toward the inside of the acoustic casing, and includes a plurality of through holes having a very small diameter with respect to the front part of the casing. It is preferable that decorative concave portions having substantially the same diameter as the sound emitting holes are distributed and formed on the surface of the front portion of the housing that forms the shape.

  According to the present invention, the sound emitting hole is composed of a plurality of through holes having a very small diameter with respect to the front part of the housing, and the front surface of the housing front part has substantially the same diameter as the through hole of the sound emitting hole. A decorative recess is formed. For this reason, it appears to the inspector that similar small-diameter holes are uniformly distributed on the front surface of the front portion of the housing. As a result, the appearance of the image display device can be brought closer to a flat, substantially flat plate shape with less unevenness, and the appearance of the image display device can be improved.

As an embodiment of the present invention, a rear projector is employed in the image display device.
Hereinafter, a rear projector according to the present embodiment will be described with reference to the drawings.
FIG. 1 is a perspective view of a rear projector 1 according to the present embodiment as viewed from the front side. 2 is a view of the rear projector 1 as seen from the back side, and FIG. 3 is a view of the rear projector 1 as seen from the left side. In the present embodiment, the front-rear direction and the left-right direction refer to the front-back direction and the left-right direction when the rear projector 1 is viewed from the front side.
The rear projector 1 modulates a light beam emitted from a light source according to input image information to form an optical image, and the formed optical image is applied to a translucent screen 2B provided in the rear projector 1. Enlarged projection.

(1) Appearance Configuration As shown in FIGS. 1 to 3, the rear projector 1 includes a box-shaped casing, and the casing has a substantially rectangular shape when viewed from the front side, and has a substantially triangular shape in vertical section. The upper cabinet 2 has a lower cabinet 3 that supports the upper cabinet 2 from below. The upper cabinet 2 and the lower cabinet 3 are fixed to each other by screws or the like.
Among these, as shown in FIG. 1, the upper cabinet 2 includes a mirror case 21 as a housing rear portion that houses a reflection mirror 2 </ b> A (FIG. 4) to be described later, and a screen 2 </ b> B as an image display portion of the image display unit. And a frame 22 serving as a front portion of the housing for holding the frame.
Further, the lower cabinet 3 is a box-shaped housing having a substantially trapezoidal shape in plan view that supports the upper cabinet 2 and accommodates main components of the rear projector 1 therein.

(1-1) Front Configuration of Rear Projector 1 A frame frame 22 is arranged on the front side of the rear projector 1, that is, on the front side of the upper cabinet 2, as shown in FIG.
The frame 22 is formed in a substantially rectangular shape in front view with a size substantially the same as the dimension on the front side of a mirror case 21 (FIG. 2) described later, and is fixed to the front side of the mirror case 21 with screws or the like.
As described above, the frame frame 22 holds the screen 2B on which the optical image is projected. For this reason, a substantially rectangular opening 221 having substantially the same size as the optical image projection area of the screen 2B is formed in the approximate center of the frame frame 22, and the screen 2B is exposed from the opening 221. In addition, speaker installation portions 222 and 223 are provided on the left and right sides of the opening 221 on the back side to provide an audio output unit 7 (FIG. 9), which will be described later, as an audio output unit having a speaker 72 (FIG. 9). Yes.

  Here, the screen 2B includes a protective plate such as a Fresnel sheet, a lenticular sheet, or a glass plate. Among these, the Fresnel sheet collimates the light beam emitted from the projection lens of the optical unit described later and reflected by the reflection mirror 2A (FIG. 4) described later. Further, the lenticular sheet is configured so that the light beam transmitted through the Fresnel sheet and collimated is diffused by the lenticular sheet so that the display image can be appropriately visually recognized.

On the front side of the lower cabinet 3, a substantially rectangular opening 31 is formed at a substantially center, and a lid member 31 </ b> A that opens and closes the opening 31 by rotating up and down is provided.
Although not shown in detail in the opening 31, a front panel as a front operation panel is provided. On the left side of the front panel, various operation switches for adjusting volume and image quality, a D-Sub terminal as a PC (Personal Computer) connection terminal, a stereo audio input terminal, a video input terminal, an S terminal, and the like are arranged. Has been. Further, on the right side portion of the front panel, various semiconductor memory cards are inserted, and a card reader for reading data from the cards is provided. A power switch 32 is provided on the right side of the opening 31. These front panel and power switch 32 are electrically connected to a control board 5 (FIG. 5) described later.
In addition, leg portions 33 are formed at the front left and right ends of the lower cabinet 3.

(1-2) Rear Configuration of Rear Projector 1 The rear side of the rear projector 1 is configured by a mirror case 21 and a lower cabinet 3 of the upper cabinet 2 as shown in FIGS.
Among these, the mirror case 21 is a synthetic resin box-shaped housing having a substantially triangular longitudinal section. The mirror case 21 is located on the left and right sides of the rear wall 211 and the bottom wall 212, the rear wall 211 constituting the rear surface of the rear projector 1, the bottom wall 212 connected to the lower end of the rear wall 211. It consists of a pair of side walls 213 and 214. Further, on the front side of the mirror case 21, extending portions 215 and 216 that are substantially orthogonal to the side walls 213 and 214 and extend away from each other, that is, in the left-right direction of the rear projector 1 are formed.

The back wall 211 has a substantially trapezoidal shape in plan view with the long side positioned upward, and is formed so as to be inclined toward the lower rear side. A reflection mirror 2A (FIG. 4) described later is supported at a predetermined angle on the inner surface of the back wall 211.
The pair of side walls 213 and 214 are formed so as to connect the left and right ends of the back wall 211 and the bottom wall 212, and are formed so as to incline inward toward the rear.
The extended portions 215 and 216 are formed larger than the vertical dimension of the side walls 213 and 214, and bulged portions 215A and 216A bulged toward the back surface are formed at substantially the center portion. An audio output unit 7 (FIG. 9), which will be described later, is provided at a portion where the bulging portions 215A and 216A and the speaker installation portions 222 and 223 (FIG. 1) of the frame 22 are opposed to each other.

On the back side of the lower cabinet 3, a first recess 34 is formed on the left side in FIG. 2, and a second recess 35 is formed on the right side.
Of these, the first recess 34 is formed with a substantially square lamp replacement port 34A, and the lamp replacement port 34A is covered with a lamp cover 34B. The lamp replacement port 34A is opened by removing the lamp cover 34B, and the light source device 41 (FIG. 8) of the optical unit 4 (FIG. 8) described later can be replaced via the lamp replacement port 34A. ing.
The second recess 35 is provided with a power cable 35A and a rear panel 35B as a back side operation panel. Of these, specifically, the rear panel 35B is provided with a DVI (Digital Visual Interface) terminal as a PC connection terminal, an antenna input terminal, a plurality of video / audio input / output terminals, and the like.

An intake port 36 (36A, 36B) for introducing cooling air for cooling electronic components housed in the lower cabinet 3 is formed below the first recess 34 and the second recess 35.
Further, exhaust ports 37 (37A, 37B, 37C) are formed on the left side of the first recess 34 and the right side of the second recess 35. These exhaust ports 37 </ b> A to 37 </ b> C are openings through which air that has cooled various devices in the lower cabinet 3 is discharged, and are formed in a slit shape.
Among these, the 1st exhaust port 37A formed in the left side of the 1st recessed part 34 exhausts the air which cooled the light source device 41 (FIG. 5) and the light source drive block 62 (FIG. 6) mentioned later. The second exhaust ports 37B and 37C formed on the right side of the second recess 35 discharge air that has cooled the control board 5 (FIG. 5) and the power supply block 61 (FIG. 6), which will be described later.

(2) Internal Configuration (2-1) Internal Configuration of Upper Cabinet 2 FIG. 4 is a diagram showing an internal configuration of the upper cabinet 2. Specifically, FIG. 4 is a front perspective view of the rear projector 1 with the screen 2B removed from the state of FIG.
As shown in FIG. 4, a reflection mirror that reflects a light beam as an optical image emitted from a projection lens 46 of an optical unit 4 (FIG. 8), which will be described later, provided inside the lower cabinet 3 is provided inside the upper cabinet 2. 2A is stored. The reflection mirror 2A is a general mirror formed in a substantially trapezoidal shape in plan view substantially the same as the shape of the back wall 211 (FIG. 2), and is mounted on the inside of the back wall 211 (FIG. 2) of the upper cabinet 2. It is attached with an inclination so that the long side of the shape is on the upper side. The inclination angle of the reflection mirror 2A is set based on the set positional relationship between the screen 2B (FIG. 1) mounted on the front side and the reflection of the image by the projection lens 46 of the optical unit 4 (FIG. 8) described later. ing.

The bottom wall 212 of the mirror case 21 has a substantially trapezoidal shape in plan view with the long side positioned on the front side. As shown in FIGS. 2 and 3, the bottom wall 212 is formed so as to incline upward toward the back side. The bottom wall 212 has a back wall 211 at the end on the back side, and a side wall at the left and right ends. 213, 214.
As shown in FIG. 4, a substantially rectangular cutout 212 </ b> A is formed in the bottom wall 212 at a substantially central portion on the front side, and a projection lens 46 of the optical unit 4 (FIG. 8) described later is exposed. A bulging portion 212B bulging upward is formed on the left side of the notch 212A. The bulging portion 212B is formed at a position corresponding to the power supply block 61 of the power supply unit 6 (FIG. 5) described later.

(2-2) Internal Configuration of Lower Cabinet 3 FIG. 5 is a diagram showing an internal configuration of the lower cabinet 3. More specifically, FIG. 5 is a rear perspective view of the rear projector 1 with the outer case on the rear side of the lower cabinet 3 removed from the state of FIG. FIG. 6 is a plan view schematically showing the internal configuration of the lower cabinet 3.
Inside the lower cabinet 3 are an optical unit 4 that forms an image, a control board 5 that controls the drive of the entire rear projector 1, a power supply unit 6 that supplies driving power to each electronic component that constitutes the rear projector 1, and the like. Storing. Specifically, the optical unit 4, the control board 5, and the power supply unit 6 are installed on the bottom surface 39 of the lower cabinet 3 along the screen 2 </ b> B held by the upper cabinet 2. That is, main processing in the rear projector 1 such as image formation is executed by the components housed in the lower cabinet 3.
Among these, as shown in FIGS. 5 and 6, the optical unit 4 is arranged on the right side from the approximate center of the lower cabinet 3, that is, on the left side when viewed from the back side. Further, the control board 5 and the power supply unit 6 are arranged from the approximate center of the lower cabinet 3 to the left side, that is, from the approximate center to the right side as viewed from the back side.

(3) Configuration of Optical Unit 4 FIG. 7 is a perspective view showing the optical unit 4. FIG. 8 is a schematic diagram showing an optical system of the optical unit 4.
The optical unit 4 as an image forming part of the image display unit modulates the light beam emitted from the light source device 41 according to image information input by the liquid crystal panel 451 to form an optical image, and the formed optical image The projection lens 46 projects an enlarged image onto the screen 2B (FIG. 1) via the reflection mirror 2A (FIG. 4). As shown in FIG. 7, the optical unit 4 is mounted on an optical unit mounting table 38 provided on the upper surface of the bottom surface 39 (FIG. 5) of the lower cabinet.
In addition, this optical unit mounting base 38 is comprised from several plate-shaped member, and is a plate-shaped member for fixing the optical unit 4 to a predetermined position.

  As shown in FIG. 8, such an optical unit 4 includes a light source device 41, an integrator illumination optical system 42, a color separation optical system 43, a relay optical system 44, an electro-optical device 45, and a projection optical device. Projection lens 46, an optical component casing 47 that houses these projection lenses 46, and a head body 48 that holds and fixes the projection lens 46.

  The light source device 41 includes a light source lamp 411 as a radiation light source, a reflector 412, an explosion-proof glass 413, and a light source lamp box 414 that is a casing made of a synthetic resin that houses them. Then, the light source device 41 reflects the radial light beam emitted from the light source lamp 411 by the reflector 412 into a parallel light beam, and emits the parallel light beam to the outside through the explosion-proof glass 413.

Among these, the light source lamp 411 is a high-pressure mercury lamp in the present embodiment. In addition to a high-pressure mercury lamp, a metal halide lamp, a halogen lamp, or the like can be employed. Moreover, although the parabolic mirror is employ | adopted as the reflector 412, you may employ | adopt what combined the parallelizing concave lens and the ellipsoidal mirror instead of the parabolic mirror.
The explosion-proof glass 413 is a translucent glass member that closes the opening of the reflector 412 so that when the light source lamp 411 is ruptured, the fragments of the light source lamp 411 are not scattered from the light source lamp box 414 to the outside. It is configured.
As shown in FIG. 7, the light source lamp box 414 is formed with a pair of handles 414 </ b> A extending toward the back when the light source device 41 is housed in the rear projector 1. In this case, the light source lamp box 414 is configured to be easily gripped. When the light source device 41 needs to be replaced due to the life or damage of the light source lamp 411, the lamp cover 34B (FIG. 2) is opened and the light source device is opened from the lamp replacement port 34A (FIG. 2). 41 is configured to be exchangeable.

The integrator illumination optical system 42 is an optical system for illuminating image forming regions of three liquid crystal panels 451 (described later) constituting the electro-optical device 45 substantially uniformly. The integrator illumination optical system 42 includes a first lens array 421, a second lens array 422, a polarization conversion element 423, and a superimposing lens 424, as shown in FIG.
The first lens array 421 has a configuration in which small lenses having a substantially rectangular outline when viewed from the optical axis direction are arranged in a matrix, and each small lens receives a plurality of light beams emitted from the light source device 41. It is divided into partial luminous fluxes.
The second lens array 422 has substantially the same configuration as the first lens array 421, and has a configuration in which small lenses are arranged in a matrix. The second lens array 422 has a function of forming an image of each small lens of the first lens array 421 together with the superimposing lens 424 on a liquid crystal panel 451 described later.

The polarization conversion element 423 is disposed between the second lens array 422 and the superimposing lens 424. Such a polarization conversion element 423 converts the light from the second lens array 422 into approximately one type of linearly polarized light, thereby improving the light use efficiency in the electro-optical device 45.
Specifically, each partial light converted into substantially one type of linearly polarized light by the polarization conversion element 423 is finally substantially superimposed on a liquid crystal panel 451 described later of the electro-optical device 45 by the superimposing lens 424. Since the rear projector 1 using the liquid crystal panel 451 of the type that modulates polarized light can use only one type of linearly polarized light, almost half of the light from the light source lamp 411 that emits other types of randomly polarized light is not used. Therefore, by using the polarization conversion element 423, the light beam emitted from the light source lamp 411 is converted into substantially one type of linearly polarized light, and the light use efficiency in the electro-optical device 45 is enhanced.
Such a polarization conversion element 423 is introduced in, for example, Japanese Patent Laid-Open No. 8-304739.

  The color separation optical system 43 includes two dichroic mirrors 431 and 432 and a reflection mirror 433, and a plurality of partial light beams emitted from the integrator illumination optical system 42 by the dichroic mirrors 431 and 432 are red (R) and green. (G) and blue (B) have a function of separating into three color lights.

The relay optical system 44 includes an incident side lens 441, a relay lens 443, and reflection mirrors 442 and 444, and converts red light, which is color light separated by the color separation optical system 43, into red light described later of the electro-optical device 45. The liquid crystal panel has a function of leading up to the liquid crystal panel 451R.
At this time, the dichroic mirror 431 of the color separation optical system 43 transmits the red light component and the green light component of the light beam emitted from the integrator illumination optical system 42 and reflects the blue light component. The blue light reflected by the dichroic mirror 431 is reflected by the reflection mirror 433, passes through the field lens 455, and reaches a later-described blue light liquid crystal panel 451 B of the electro-optical device 45. The field lens 455 converts each partial light beam emitted from the second lens array 422 into a light beam parallel to the central axis (principal ray). The same applies to the field lens 455 provided on the light beam incident side of the other light modulators for green light and red light.

Of the red light and green light transmitted through the dichroic mirror 431, the green light is reflected by the dichroic mirror 432, passes through the field lens 455, and reaches the liquid crystal panel 451G for green light. On the other hand, the red light passes through the dichroic mirror 432, passes through the relay optical system 44, passes through the field lens 455, and reaches the liquid crystal panel 451R for red light.
Note that the relay optical system 44 is used for red light because the optical path length of red light is longer than the optical path lengths of the other color lights, thereby preventing a reduction in light utilization efficiency due to light divergence or the like. It is to do. That is, this is to transmit the partial light beam incident on the incident side lens 441 to the field lens 455 as it is. The relay optical system 44 is configured to pass red light of the three color lights, but is not limited thereto, and may be configured to pass blue light or green light, for example.

  The electro-optical device 45 modulates an incident light beam according to image information to form a color image, and three incident-side polarizing plates 452 into which the respective color lights separated by the color separation optical system 43 are incident. And three liquid crystal panels 451 (the red light liquid crystal panel 451R, the green light liquid crystal panel 451G, and the blue light liquid crystal panel) as light modulation elements arranged in the latter stage of the optical path of each incident side polarizing plate 452. 451B), three exit-side polarizing plates 453 disposed in the rear stage of the optical path of each liquid crystal panel 451, and a cross dichroic prism 454 as a color synthesizing optical device. The incident-side polarizing plate 452, the liquid crystal panel 451, the exit-side polarizing plate 453, and the cross dichroic prism 454 are integrally unitized. Note that the incident-side polarizing plate 452, the liquid crystal panel 451, and the emission-side polarizing plate 453 are arranged at predetermined intervals, although not specifically illustrated.

  The incident-side polarizing plate 452 receives the respective color lights whose polarization directions are aligned in approximately one direction by the polarization conversion element 423, and is substantially the same as the polarization axis of the light beams aligned by the polarization conversion element 423 among the incident light beams. Only polarized light in the direction is transmitted, and other light beams are absorbed. The incident-side polarizing plate 452 has a configuration in which a polarizing film is pasted on a translucent substrate such as sapphire glass or quartz.

  The liquid crystal panel 451 has a configuration in which liquid crystal, which is an electro-optical material, is hermetically sealed between a pair of transparent glass substrates, and the liquid crystal panel 451 is in the image forming area in accordance with a drive signal output from a control substrate described later. The orientation state is controlled, and the polarization direction of the polarized light beam emitted from the incident side polarizing plate 452 is modulated.

  The exit-side polarizing plate 453 has substantially the same configuration as the incident-side polarizing plate 452, and out of the light beams emitted from the image forming area of the liquid crystal panel 451, the polarization axis orthogonal to the light transmission axis of the incident-side polarizing plate 452. Only the light beam having a light is transmitted and other light beams are absorbed.

  The cross dichroic prism 454 is an optical element that synthesizes an optical image modulated for each color light emitted from the emission side polarizing plate 453 to form a color image. The cross dichroic prism 454 has a square shape in plan view in which four right-angle prisms are bonded together, and two dielectric multilayer films are formed at the interface where the right-angle prisms are bonded together. These dielectric multilayer films reflect each color light emitted from the liquid crystal panels 451R and 451B via the emission side polarizing plate 453, and transmit the color light emitted from the liquid crystal panel 451G via the emission side polarizing plate 453. In this manner, the color lights modulated by the liquid crystal panels 451R, 451G, and 451B are combined to form a color image.

  The projection lens 46 has a configuration in which a plurality of lenses and a mirror that deflects an incident light beam are housed in a lens barrel, and enlarges the color image emitted from the electro-optical device 45 to reflect the reflection mirror 2A (FIG. Toward 4), that is, the color image emitted toward the front is bent upward and projected. The projection lens 46 is disposed on the light beam exit side of the electro-optical device 45 and is fixed to a head body 48 described later. Further, as shown in FIG. 4, the projection lens 46 is disposed substantially at the center on the front side of the lower cabinet 3 and is exposed to the inside of the mirror case 21 from the notch 212 </ b> A formed in the bottom wall 212 of the upper cabinet 2. .

  As shown in FIG. 8, the optical component housing 47 has a predetermined illumination optical axis A set therein, and arranges the optical components 42 to 45 described above at predetermined positions with respect to the illumination optical axis A. The optical component casing 47 includes a light source device storage member 471, a component storage member 472, and a lid-like member 473.

Although not shown in detail, the light source device housing member 471 is formed in a box shape having a substantially U-shaped cross section that is open on the back side. When the light source device 41 is stored in the light source device storage member 471, the light source lamp box 414 is slid toward the front side with respect to the light source device storage member 471. Further, when the light source device 41 is taken out from the light source device storage member 471, the light source lamp box 414 is slid toward the back side.
The light source device storage member 471 is connected to the component storage member 472, and an opening 471A is formed at the connection portion with the component storage member so that the light beam emitted from the light source lamp 411 of the light source device 41 passes. Has been.

The component storage member 472 is configured as a synthetic resin box-shaped housing having a substantially U-shaped cross-section with an upper opening. As described above, the light source device storage member 471 is connected to one end side of the component storage member 472, and the head body 48 that holds and fixes the electro-optical device 45 and the projection lens 46 is attached to the other end side. Among these, the light beam emitted from the light source device 41 stored in the light source device storage member 471 passes through the component storage member 472 at the end of the component storage member 472 connected to the light source device storage member 471. Thus, a substantially rectangular opening 472A is formed.
A plurality of grooves are formed inside the component storage member 472, and the optical components 421 to 424, 431 to 433, 441 to 444, and 455 are positioned and fixed in the grooves so as to be fitted from above.

In this component storage member 472, as shown in FIG. 8, each end surface of the emission side end portion in a U-shape in plan view that emits the light beam emitted from the light source lamp 411 of the light source device 41 and guided therein A notch 472B is formed as a light beam passage opening for passing light, and a field lens 455 is attached to the peripheral portion of the notch 472B so as to close the notch 472B.
In addition, as shown in FIG. 7, the component storage member 472 has a plurality of leg portions 472C formed on the outer surface. These leg portions 472 </ b> C are for fixing the component storage member 472 to the optical unit mounting table 38 formed on the bottom inner surface of the lower cabinet 3. The component storage member 472 is screwed to the optical unit mounting table 38 through a hole 472C1 formed in the leg portion 472C.

As shown in FIG. 7, the lid-like member 473 has a shape corresponding to the planar shape of the component storage member 472, and is a synthetic resin casing attached so as to close the upper opening of the component storage member 472. is there.
An opening (not shown) is formed at a position corresponding to the polarization conversion element 423 (FIG. 8) of the lid-like member 473, and a cooling fan for cooling the polarization conversion element 423 is provided above the opening. 91 is provided.

As shown in FIG. 8, a head body 48 that holds and fixes the projection lens 46 is attached to the end of the component housing member 472 on the light beam exit side.
The head body 48 is made of a metal material such as an aluminum alloy or a magnesium alloy, and integrates the electro-optical device 45 and the projection lens 46 and attaches the integrated unit to the optical component casing 47. is there.
Although not shown in detail, the head body 48 has a substantially inverted T shape when viewed from the side, and is sandwiched between the horizontal portion 481 on the light beam incident side, the horizontal portion 482 on the light beam exit side, and the horizontal portions 481 and 482. The vertical portion 483 stands vertically from the horizontal portions 481 and 482.
Among these, the electro-optical device 45 is fixed to the horizontal portion 481 on the light beam incident side, and the projection lens 46 is fixed to the horizontal portion 482 on the light beam emission side. The vertical portion 483 is formed with an opening 483A for guiding the light beam emitted from the electro-optical device 45 to the projection lens 46.

(4) Configuration of Control Board 5 The control board 5 is arranged vertically on the left side of the projection lens 46, that is, on the right side of the center in FIGS. 5 and 6, in order to prevent EMI (Electromagnetic Interference). The whole is covered with a metal shield member in which a plurality of holes are formed. The control board 5 is configured as a circuit board on which a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like are mounted, and is provided on each of the front panel and the rear panel 35B (FIG. 2). A rear projector including the liquid crystal panel 451 (FIG. 8) of the optical unit 4 (FIG. 8) by processing image information, audio information input from the connection terminal and an operation signal from an operation button provided on the front panel. 1 (FIG. 1) overall drive control is performed.

(5) Configuration of Power Supply Unit 6 The power supply unit 6 converts an alternating current input from the outside into a direct current and supplies driving power to each electronic component constituting the rear projector 1 (FIG. 1).
As shown in FIGS. 5 and 6, the power supply unit 6 is disposed on the right side of the lower cabinet 3 and is connected to the power supply block 61 connected to the power supply cable 35 </ b> A (FIG. 2) and the front side of the light source device housing member 471. The light source drive block 62 is disposed and supplies drive power to the light source lamp 411 (FIG. 8) that constitutes the light source device 41.
5 and 6, the power supply block 61 is disposed on the right side of the lower cabinet 3 when viewed from the back side, and is disposed on the opposite side of the light source device 41 with the projection lens 46 interposed therebetween. ing. The power supply block 61 converts the commercial alternating current input via the power supply cable 35A (FIG. 2) into a direct current, boosts and reduces the voltage to a voltage corresponding to each electronic component, and then the electronic components such as the light source drive block 62 and the control board 5 Supply parts.
The light source drive block 62 rectifies and transforms the direct current supplied from the power supply block 61 to generate an alternating current rectangular wave current, and supplies the alternating current rectangular wave current to the light source lamp 411 (FIG. 8) of the light source device 41. . The light source drive block 62 is electrically connected to the control board 5 described above, and lighting control of the light source lamp 411 (FIG. 8) is performed by the control board 5 via the light source drive block 62.

(6) Configuration of Audio Output Unit 7 FIGS. 9 to 11 show an audio output unit 7 as an audio output unit. 9 is a perspective view of the audio output unit 7 on the left side, FIG. 10 is a rear view of the front internal structure of the audio output unit 7 of FIG. 9, and FIG. 11 is a view of the audio output unit 7 of FIG. FIG.
The audio output unit 7 is electrically connected to the above-described control board 5 (FIGS. 5 and 6), and outputs audio according to the drive signal output from the control board 5 (FIGS. 5 and 6). To do. As shown in these drawings, the audio output unit 7 includes an enclosure 71 as an acoustic casing provided at the left and right edges of the upper cabinet 2 and an enclosure internal structure housed in the enclosure 71. Since the left and right audio output units 7 have the same configuration, the left side will be described as a representative.

  The enclosure 71 reverberates the sound inside to amplify the sense of reality and emit the sound to the outside. The enclosure 71 is formed by combining two housings on the front side and the rear side. That is, the enclosure 71 is formed by joining the speaker installation portion 222 formed on the frame frame 22 around the screen 2B and the bulging portion 215A formed on the extending portion 215 of the mirror case 21 at the joint surface B. Is done. The enclosure 71 has a bass-reflex type configuration that can enhance the sound in the bass region by the following structure.

Inside the enclosure 71, a speaker 72 is attached to the back surface of the speaker installation unit 222. A sound emission hole 73 for high sound is formed at a location where the speaker 72 of the speaker installation portion 222 is attached. The bulging portion 215A is provided with a duct 74 that protrudes into the enclosure 71 and whose opening end 741 is exposed to the outside.
FIG. 10 is a rear view of the speaker installation unit 222. As shown in FIG. 10, the loudspeaker 72 has a high sound speaker 721 attached upward and a low sound speaker 722 attached downward. The treble speaker 721 emphasizes and outputs the sound in the high sound region, and the low sound speaker 722 outputs the sound in the low to high sound region. The high-frequency speaker 721 and the low-frequency speaker 722 each have a sound emission opening at a protruding portion that protrudes in a cylindrical shape from the back surface of the speaker installation portion 222 with the sound emission opening 723 formed on the sound emission side facing forward. The peripheral edge of 723 is fixed with a screw or the like. Accordingly, as shown in FIG. 11, the high-pitched speaker 721 and the low-pitched speaker 722 are fixed between the back surface of the speaker installation portion 222, that is, the extending portion 215 </ b> A formed on the side portion of the mirror case 21. Fixed with distance clearance.

The sound emitting hole 73 is a hole for emitting the sound in the high sound region emitted from the high sound speaker 721 and the low sound speaker 722 to the outside. As shown in FIG. 11, the sound emitting hole 73 is formed by penetrating through the speaker installation portion 222 toward the inside of the enclosure 71, and includes a plurality of through holes 731 having a very small diameter with respect to the speaker installation portion 222. The through-holes 731 are distributed in a circular shape so as to substantially face the high-frequency speaker 721 and the low-frequency speaker 722 and the sound emission opening 723.
On the surface of the speaker installation portion 222 excluding the distribution area of the sound emission holes 73, decorative concave portions 732 having the same diameter as the through holes 731 are formed and distributed at the same density as the through holes 731.

  Here, since the decorative concave portions 732 having the same diameter and the same distribution density as the through holes 731 of the sound emitting holes 73 are formed on the surface of the speaker installation portion 222 (223), the observer places the speaker installation portion 222 on the surface. It appears that similar small diameter holes are uniformly distributed on the surface of (223). As a result, the appearance of the speaker installation unit 222 (223) and the appearance of the rear projector 1 can be brought closer to a flat and substantially flat plate shape with less unevenness. That is, the appearance of the rear projector 1 can be improved.

  The duct 74 can reinforce the sound in the low sound region by resonating the sound emitted from the backs of the high sound speaker 721 and the low sound speaker 722 together with the enclosure 71. The duct 74 is injection-molded integrally with the mirror case 21, and as shown in FIG. 11, a circular opening end 741 exposed to the outside below the bulging portion 215A, and the opening end 741 to the inside of the enclosure 71. The duct main body 742 extends in the horizontal direction and has a circular cross section. In the vicinity of the periphery of the open end 741, a recess 743 is formed that is depressed toward the inside of the enclosure 71 during molding. Here, the pipe length and the pipe diameter of the duct 74 are preferably adjusted according to the shape of the enclosure 71 and the echo sound desired to be realized.

Thus, since the duct 74 is formed to protrude toward the inside of the enclosure 71 at the bulging portion 215A (215B), the opening end 741 is seen from the observer viewing the rear projector 1 from the front side. The recess 743 in the vicinity of is not visible. For this reason, the appearance of the rear projector 1 can be improved.
Further, since the bass reflex type having the duct 74 is adopted in the enclosure 71, the sound in the bass region can be enhanced by resonating the sound emitted from the back of the speaker 72 inside the enclosure 71 and the duct 74. it can. As a result, it is possible to provide a realistic sound to the inspector.

  In order to assemble such an audio output unit 7, first, the mirror case 21 provided with the duct 74 on the front surface of the bulging portion 215A is injection-molded. Next, the speaker 72 is attached to the back surface of the speaker installation part 222 of the frame 22. In order to assemble the upper cabinet 2, when the back side of the frame frame 22 and the front side of the mirror case 21 are combined to face each other, the speaker installation part 222 and the bulging part 215 </ b> A are combined on the joint surface B, and at the same time, the speaker 72 An enclosure 71 is formed in which an internal structure such as a duct 74 is accommodated. The audio output unit 7 is assembled in this way and is provided in the rear projector 1.

Here, as described above, the appearance of the rear projector 1 can be improved by the decorative recess 732 and the duct 74 formed in the bulging portion 215A (215B), so that the speaker installation portion 222 (223) can be improved. There is no need to attach a cover for decoration on the surface. Thereby, the number of parts of the rear projector 1 can be suppressed.
Furthermore, since there is no need to attach a cover or the like as a decoration to the surface of the speaker installation portion 222 (223), the thickness of the audio output unit 7 can be suppressed. That is, the audio output unit 7 can be made as thin as possible, and even if the audio output unit 7 is provided in the thin rear projector 1, advantages such as space saving and excellent appearance of the rear projector 1 are not impaired.
Moreover, since the duct 74 is integrally injection-molded together with the bulging portion 215A (215B), the number of parts and the number of manufacturing steps can be suppressed. For this reason, the productivity of the rear projector 1 can be improved.

The best configuration for implementing the present invention has been disclosed in the above description, but the present invention is not limited to this. That is, the invention has been illustrated and described primarily with respect to particular embodiments, but may be configured for the above-described embodiments without departing from the scope and spirit of the invention. Various modifications can be made by those skilled in the art in terms of materials, quantity, and other detailed configurations.
Therefore, the description limiting the shape, material, etc. disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such is included in this invention.

  In the present invention, the bulging portions 215A and 215B are formed such that the open ends 741 are exposed to the outside, and the duct body 742 is formed on the front side of the bulging portions 215A and 216B so as to be housed in the enclosure 71. It only has to be. That is, the detailed shape and formation position of the duct 74 may be adjusted according to the echo sound to be realized. For example, the duct 74 may not be circular in cross section, and may be rectangular in cross section or elliptical in cross section.

  In the above embodiment, the sound emitting hole 73 and the decorative recess 732 have a circular cross section. However, the present invention is not limited to this, and it is difficult for the inspector to distinguish each other, and the surface of the speaker installation portion 222 is uneven. Any other cross-sectional shape may be used as long as it appears to be a substantially flat surface with little.

  In the above embodiment, the rear projector 1 using three light modulation devices is used. However, the present invention is not limited to this. For example, a rear projector using only one light modulation device and a rear projector using two light modulation devices. Alternatively, a rear projector using four or more light modulation devices may be used. Further, although the liquid crystal panel 451 is employed as the light modulation device, the present invention is not limited thereto, and a light modulation device other than liquid crystal such as a device using a micromirror may be employed. Further, instead of a transmissive light modulator, a reflective light modulator may be used.

  In the embodiment, the rear projector 1 is exemplified as the image display device. However, the present invention is not limited to this, and other image display devices may be used as long as they form an image according to image information. Examples of such an image display device include a CRT (Cathode-Ray Tube) display, a liquid crystal display, and a plasma display.

  The present invention can be used for thin video display devices such as liquid crystal televisions and rear projectors.

The perspective view which looked at the rear projector which concerns on one Embodiment of this invention from the front side. The perspective view which looked at the rear projector in the said embodiment from the back side. The side view which looked at the rear projector in the said embodiment from the left side. The perspective view which shows the internal structure of the upper cabinet in the said embodiment. The perspective view which shows the internal structure of the lower cabinet in the said embodiment. The schematic diagram which shows the internal structure of the lower cabinet in the said embodiment. The perspective view which shows the optical unit in the said embodiment. The schematic diagram which shows the optical system of the optical unit in the said embodiment. The perspective view which looked at the audio | voice output unit in the said embodiment from the front side. The perspective view which looked at the speaker installation part of the audio | voice output unit of FIG. 9 from the back side. Sectional drawing which looked at the audio | voice output unit of FIG. 9 from the left side.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Rear projector (image display apparatus), 2 ... Upper cabinet, 2A ... Screen (image display part), 21 ... Mirror case, 215, 216 ... Extension part, 215A, 215B ... Expansion part, 22 ... Frame frame, 222, 223 ... Speaker installation unit, 4 ... Optical unit (image display unit), 7 ... Audio output unit (audio output unit), 71 ... Enclosure (acoustic housing), 72 ... Speaker, 73 ... Sound emission hole, 731 ... Through-hole, 732 ... decorative recess, 74 ... duct, 741 ... open end

Claims (2)

An image display unit that forms and displays an image according to input image information, an audio output unit that outputs audio according to audio information input together with the image information, the image display unit, and the audio output unit An image display device comprising a box-shaped housing for storing
The housing includes a housing front part from which the image display unit is exposed, and a housing rear part covering the rear side of the housing front part,
The audio output unit includes an acoustic casing formed in a box shape by the front part of the casing and the rear part of the casing, a speaker attached to the front part of the casing in a state of being housed in the acoustic casing, A sound emission hole for high sound formed in the front part of the casing to which a speaker is attached and a rear part of the casing forming the acoustic casing, and projecting from the rear part of the casing to the inside of the acoustic casing. An image display device comprising a duct having an open end exposed to the outside. The image display device according to claim 1,
The sound emitting hole is formed by penetrating the housing front part toward the inside of the acoustic housing, and includes a plurality of through holes having a very small diameter with respect to the housing front part.
An image display device, wherein decorative concave portions having substantially the same diameter as the sound emitting holes are distributed and formed on a front surface of the front portion of the housing forming the acoustic housing.

Images