JP2009229617A - Projection-type image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection-type image display device by which a viewer around a projector can listen to a voice of a more appropriate volume. <P>SOLUTION: The projection-type image display device that modulates the light emitted from a light source through a display device (liquid crystal panel), and magnifies and projects an image, comprises a speaker 50 for amplifying and outputting an input voice signal. The speaker 50 has nondirection characteristics, and is disposed on the top board in the body case. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a projection display apparatus such as a liquid crystal projector, and more particularly to a projection display apparatus having a speaker.

As this type of projection display apparatus, a pair of left and right speakers facing the rear is provided behind the projector, and the left and right speakers are arranged according to the installation angle between the projector and the screen detected when performing keystone correction. By controlling the volume, it is known that audio can be heard in a more appropriate volume for both viewers close to the projector and viewers far from the projector (for example, Patent Documents). 1).
JP 2004-163453 A

  However, speakers are generally directional, and viewers who are at the side of the projector or in front of the projector may not be able to hear the sound in an appropriate volume from the speakers, making it difficult to hear the sound. .

  Accordingly, the present invention has been made to solve such a problem, and provides a projection display apparatus that allows a viewer around the projector to hear sound with a more appropriate volume. Let it be an issue.

  Means for solving the above-mentioned problems include a speaker for amplifying and outputting an input audio signal in a projection-type image display apparatus that modulates light emitted from a light source via a display device and enlarges and projects an image. And the speaker has omnidirectional characteristics.

  In the means for solving the above problems, the speaker may be provided on a top surface in a main body case of the projection display apparatus.

  According to the configuration of the present invention, it is possible to obtain an effect such as being able to listen to a sound at an appropriate volume for a viewer around the projection display apparatus.

  The projection display apparatus according to the first embodiment of the present invention will be described in detail below with reference to FIGS.

  As shown in FIGS. 1 and 2, the projection display apparatus of the present embodiment shows a three-plate liquid crystal projector 30 as an example. In the main body case 41 of the liquid crystal projector 30, an optical system 42 from the light source 1 described later to the projection lens 16 is disposed.

  FIG. 2 shows an optical system 42 disposed in the main body case 41. The light emitting unit in the light source 1 is composed of an ultra-high pressure mercury lamp, a metal halide lamp, a xenon lamp or the like, and the irradiation light is emitted as parallel light by the parabolic reflector 2 and guided to the integrator lens 4.

  The integrator lens 4 is composed of a pair of lens groups (fly eye lenses) 4a and 4b, and each lens portion guides light emitted from the light source 1 to the entire surfaces of liquid crystal light valves 31, 32, and 33 described later. Thus, the partial luminance unevenness existing in the light source 1 is averaged, and the light amount difference between the center of the screen and the peripheral portion is reduced. The light passing through the integrator lens 4 is guided to the first dichroic mirror 7 after passing through the polarization conversion device 5 and the condenser lens 6.

  The first dichroic mirror 7 transmits light in the red wavelength band and reflects light in the cyan (green + blue) wavelength band. The light in the red wavelength band that has passed through the first dichroic mirror 7 is reflected by the reflection mirror 8 to change the optical path. The red light reflected by the reflection mirror 8 is light-modulated by passing through a lens 9 and a transmissive liquid crystal light valve 31 for red light. The light in the cyan wavelength band reflected by the first dichroic mirror 7 is guided to the second dichroic mirror 10.

  The second dichroic mirror 10 transmits light in the blue wavelength band and reflects light in the green wavelength band. The light in the green wavelength band reflected by the second dichroic mirror 10 is guided to the transmissive liquid crystal light valve 32 for green light through the lens 11 and is modulated by being transmitted therethrough. The light in the blue wavelength band that has passed through the second dichroic mirror 10 is guided to the blue-light transmissive liquid crystal light valve 33 through the total reflection mirror 12, total reflection mirror 13, and lens 14, and is transmitted therethrough. It is optically modulated.

  Each of the liquid crystal light valves 31, 32, and 33 as a display device is formed by enclosing liquid crystal between the incident-side polarizing plates 31a, 32a, and 33a and a pair of glass substrates (with pixel electrodes and alignment films formed). It is comprised from the panel parts 31b, 32b, 33b, and the output side polarizing plates 31c, 32c, 33c.

  The modulated light (each color video light) modulated by passing through the liquid crystal light valves 31, 32, 33 is synthesized by the cross dichroic prism 15 to become color video light. The color image light is enlarged and projected by the projection lens 16 and displayed on a screen (not shown). The projection lens 16 is movable back and forth (up and down in FIG. 2) by a stepping motor 22.

  As shown in FIG. 1, a speaker 50 that amplifies and outputs an input audio signal is provided at the approximate center of the top surface in the main body case 41. Since this speaker 50 has omnidirectional characteristics and can transmit sound in all directions of 360 degrees, all the viewers around the liquid crystal projector 30 can hear sound of an appropriate volume uniformly. Can be done.

  Further, the main body case 41 provided with the speaker 50 is formed of a member that easily transmits vibration, or is thinly formed locally so as to easily vibrate, and without providing a hole for making a sound in the main body case 41. The sound from the speaker 50 can be heard outside the main body case 41.

  Further, since a hole for making sound is not formed in the main body case 41, the dustproof performance can be improved even if the speaker 50 is provided on the top surface of the main body case 41, and the speaker is provided on the top surface of the main body case 41. By providing 50, the omnidirectionality of the speaker 50 can be further improved.

  In the first embodiment of the present invention, the speaker 50 has omnidirectional characteristics, and the sound from the speaker 50 can be heard outside the main body case 41 without providing a hole for making sound in the main body case 41. However, the present invention is not limited to this, and the body case 41 may be provided with holes for producing sound.

  3 and 4 show a second embodiment of the present invention. Note that the same parts as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  In the first embodiment, the speaker 50 having omnidirectional characteristics is provided. In the second embodiment, the liquid crystal projector 30 is connected to the external speaker 60 having an amplifier.

  Audio output to the external speaker 60 is performed from the audio terminal 65 on the back surface of the main body case 41. The audio terminal 65 is configured to output an audio signal and simultaneously supply power to the amplifier of the external speaker 60. A terminal (not shown) provided on the cord 70 of the external speaker 60 is an audio terminal. By connecting to 65, sound can be output to the external speaker 60 and power can be supplied to the external speaker 60.

  Therefore, it is not necessary to prepare a power supply for the external speaker 60 in particular, and power can be supplied to the external speaker 60 only by an audio output connection with the projector 30.

  In the first and second embodiments of the present invention, the liquid crystal projector 30 using the liquid crystal display panel is shown. However, the present invention is not limited to this, and the present invention is also applicable to a projection type video display device having another video light generation system. The present invention can be applied. In addition to the front projection type, the present invention can be applied to a rear projection type image display device. The present invention can also be applied to a projector of a DLP (Digital Light Processing) (registered trademark of Texas Instruments (TI)) system.

1 is an external perspective view of a liquid crystal projector according to a first embodiment of the present invention. It is the block diagram which showed the optical system of the liquid crystal projector. It is an external appearance perspective view of the liquid crystal projector of 2nd Embodiment of this invention. It is a rear view of the liquid crystal projector.

Explanation of symbols

1 Light source 16 Projection lens 31 Liquid crystal light valve (display device)
32 Liquid crystal light valve (display device)
33 Liquid crystal light valve (display device)
41 Main unit case 50 Speaker

Claims (2)

In a projection display apparatus that modulates light emitted from a light source through a display device and enlarges and projects an image, the projection display apparatus includes a speaker that amplifies and outputs an input audio signal, and the speaker has omnidirectional characteristics. A projection-type image display device comprising: The projection type video display apparatus according to claim 1, wherein the speaker is provided on a top surface in a main body case of the projection type video display apparatus.