WO2010109577A1

WO2010109577A1 - Projection display device

Info

Publication number: WO2010109577A1
Application number: PCT/JP2009/055650
Authority: WO
Inventors: 恭太郎奥津
Original assignee: Ｎｅｃディスプレイソリューションズ株式会社
Priority date: 2009-03-23
Filing date: 2009-03-23
Publication date: 2010-09-30
Also published as: JPWO2010109577A1; JP5126413B2

Abstract

Influence of a strain of a case or influence of a strain of an optical base inside the case is reduced. The projection display device has the case which can be fixed to an attaching base, and a strain gage sensor (34) for detecting a strain.

Description

Projection display

The present invention relates to a projection display device that can be fixed to a mounting base.

A projector as a projection display device may be placed on a desk or a floor during use, and may be suspended from, for example, a ceiling (see Patent Documents 1-3). When the projector is suspended from the ceiling, a ceiling mount is used as an instrument for suspending the projector.

The ceiling hanger has a support part and a mounting base connected to the support part. The support portion is fixed to the ceiling, and the projector is fixed to the mounting base. In this way, the projector is suspended from the ceiling.

FIG. 1 is a perspective view showing an example of a projector attached to an attachment base. The projector 100 is fixed to the mounting base 110 while being suspended from the mounting base 110. A support portion (not shown) is connected to the mounting base, and the support portion is fixed to the ceiling, for example. The projector 100 and the mounting base 110 have screw holes and are fixed to each other by screws 122.

If the size, number, and position of the screw holes formed in the projector are different for each product, there is a problem that only a mounting base suitable for the product can be used. Therefore, the size, number, and position of screw holes formed in the housing and the mounting base are defined by standards. In this way, various types of projectors can be fixed to the same mounting base.

In recent years, various types of projectors have been manufactured. From the viewpoint of miniaturization and weight reduction, a part of the surface of the projector that cannot be seen from the outside (the bottom surface of the housing) is raised, and irregularities may be formed on the bottom surface of the housing. In order to develop various functions, various parts are housed in the housing. Depending on the parts housed in the housing, irregularities may be formed on the bottom surface of the housing.

As described above, since there are cases having various shapes of the bottom surface, the shape of the bottom surface of the housing and the shape of the mounting base do not match even if the size, number, and position of the screw holes are determined. Sometimes. In addition, it is difficult to manufacture a mounting base that fits a housing having various shapes.

Hereinafter, an example in which the housing and the mounting base are not compatible will be described with reference to FIG. FIG. 2 shows a state in which a projection type display device having irregularities formed on the bottom surface of the housing is fixed to a plate-like mounting base. When unevenness is formed on the bottom surface 104 of the housing, the convex portion 106 on the bottom surface may come into contact with the mounting base 110. At this time, a gap is generated between the screw hole 124 formed in the housing 102 and the mounting base 110. In this state, if the housing 102 is forcibly fixed by the screw 122, a load is applied to the housing 102. Usually, the mounting base 110 has higher strength than the housing 102, so that the housing 102 is distorted.

As in the above example, if the casing is forcibly fixed to a mounting base that is not suitable for the shape of the casing, there is a problem that the casing is distorted and the casing deteriorates.

Even if the shape of the housing matches the shape of the mounting base, if the strength of screw tightening varies between the screws that secure the mounting base and the housing, the housing will be distorted and the housing will be distorted. The body may deteriorate.

When the housing is distorted, the components mounted inside the housing are also distorted. A precision optical component such as a light separation component is housed inside the housing of the projection display device. The inventor of the present application has found that a further problem that a band-like shadow occurs in the projected image as a result of the distortion of the optical base affecting the optical component.

Therefore, it is desired to reduce the influence of the distortion of the casing or the optical base inside the casing.
Japanese Patent Application Publication No. 2006-34879 Japanese Patent Application Publication No. 2007-178651 Japanese Patent Application Publication No. 2007-285355 Japanese Patent Application Publication No. 2005-37474

An object of the present invention is to provide a projection display device that solves any of the above-described problems.

The first projection display device of the present invention has a casing that can be fixed to the mounting base and a strain sensor that detects strain.

The above and other objects, features, and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings, which illustrate the present invention.

It is a perspective view of the projection type display apparatus in related technology fixed to the attachment base. It is a typical top view of the projection type display apparatus in related technology fixed to the attachment base. 1 is a perspective view of a projector according to an embodiment of the invention. FIG. 4 is a perspective view of the projector shown in FIG. 3 fixed to a mounting base. It is a perspective view of the optical base provided in the housing | casing of a projector. It is a block diagram which shows the structure for displaying the detection result by a strain gauge sensor. FIG. 2 is a schematic plan view of a projector according to an embodiment fixed to a mounting base. It is a schematic diagram of the foot | leg part which the projector of FIG. 7 has. It is a schematic diagram of the foot | leg part to which the elastic member was attached.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Projector 12 Housing | casing 14 Bottom surface of housing 20 Mounting base 22 Fixing tool 22a Screw 24 Screw hole 26 Foot portion 28 Bottom surface of foot portion 30 Optical base 32 Bottom surface of optical base 34 Strain gauge sensor 40 A / D converter 42 CPU
44 Light Emitting Diode (LED)
46 On-Screen Display (OSD) Control Unit 50 Convex 60 Upper Part 62 Lower Part 64 Hinge 66 Tilt Part 70 Elastic Member

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following embodiment, the present invention will be described in detail by taking a projector as an example. However, the present invention can be applied to all projection display devices having a housing that can be fixed to the mounting base.

FIG. 3 is a perspective view of the projector according to the first embodiment. The projector 10 includes a housing 12 that can be fixed to a mounting base, and an optical base on which optical components are mounted. The optical base is provided inside the housing 12. Examples of the optical component mounted on the optical base include a photosynthetic component and a light separating component.

FIG. 4 is a perspective view of the projector fixed to the mounting base of the ceiling mount. The attachment base 20 may be a plate formed integrally with a support portion (not shown) fixed to the ceiling, for example. In this case, the projector 10 can be fixed to the lower surface of the mounting base 20. When fixing the housing 12 to the mounting base 20, the housing 12 is strongly fixed to the mounting base 20 by the fixture 22. Thereby, the projector 10 is prevented from dropping from the mounting base 20. Moreover, the mounting base 20 does not necessarily need to be installed horizontally, and may be angled with respect to a horizontal plane.

As the fixture 22, for example, a screw can be used. In this case, a screw hole 24 is formed in the projector. In the present embodiment, a foot portion 26 is formed on the bottom surface 14 of the housing to support the housing when the projector is installed, and a screw hole 24 is formed in the bottom surface 28 of the foot portion (see FIG. 3). . Here, the bottom surface 14 of the housing refers to one surface of the housing 12 that faces the mounting base 20 when the housing 12 is mounted to the mounting base 20. In the figure, four feet 26 are provided, but any number of feet may be used.

FIG. 5 is a schematic perspective view of the optical base provided inside the projector housing. The optical base 30 is provided with a strain sensor that detects distortion of the optical base. In the present embodiment, a strain gauge sensor 34 is used as a strain sensor, which detects a strain at a location where the strain sensor is attached as a change in electrical resistance. However, the strain sensor is not limited to the strain gauge sensor as long as the strain of the optical base 30 can be detected.

In this embodiment, the strain gauge sensor 34 is attached to the optical base 30. Specifically, the strain gauge sensor 34 is attached to the surface 32 of the optical base (hereinafter simply referred to as “the bottom surface of the optical base”) located toward the bottom surface 14 of the housing.

Since the bottom surface 32 of the optical base is located in the vicinity of the bottom surface 14 of the housing, it is easily affected by distortion of the bottom surface 14 of the housing. Therefore, by attaching the strain gauge sensor 34 to the bottom surface 32 of the optical base, the strain detection accuracy of the optical base 30 is improved.

As another embodiment, the strain gauge sensor 34 may be attached to the bottom surface 14 of the housing. Since the distortion of the optical base 30 is caused by the distortion of the casing 12, the distortion of the optical base 30 can be indirectly detected by detecting the distortion of the casing 12.

FIG. 6 is a block diagram showing a configuration for displaying a detection result by the strain gauge sensor. FIG. 6 shows only the configuration related to the display of the detection result. The arrow in the figure indicates the direction in which the output signal from the strain gauge sensor 34 is transmitted.

The projector 10 includes an A / D converter 40, a CPU 42 as a control unit, a light emitting diode (LED) 44 as a display unit, an on-screen display (OSD) control unit 46, Have.

When the optical base 30 is distorted, the strain gauge sensor 34 outputs an electrical signal (analog signal). The analog signal from the strain gauge sensor 34 is converted into a digital signal by the A / D converter 40. The A / D converter 40 transmits a high level signal when it receives an analog signal that is equal to or larger than a predetermined magnitude, and transmits a low level signal when it receives a smaller analog signal. Thus, the A / D converter 40 binarizes the distortion signal.

The signal digitized by the A / D converter 40 is sent to the CPU 42 as a control unit. The CPU 42 sends a signal to the LED 44 or the OSD control unit 46 in accordance with the received signal. The OSD control unit controls the OSD displayed on the screen.

In this embodiment, when the CPU 42 receives a high level signal, the CPU 42 displays a warning on a display unit such as the LED 44 or the OSD. As an example, warning can be performed by blinking the LED 44. As another example, a warning message may be displayed on the OSD displayed on the screen. As yet another example, the warning may be issued by stopping the projection of the image from the projector 10. The projector 10 can warn the user through these operations. Further, the warning is not limited to a visual one but may be a sound.

As described above, the strain sensor can cause the user to detect the occurrence of strain, so that the user can take measures such as loosening the fixture 22 that is strongly fixed to the housing 12. Thereby, the burden concerning the housing | casing 12 can be eased. Furthermore, since the distortion of the optical base 30 is also alleviated, it is possible to suppress image distortion caused by the distortion of the optical base 30.

In the above embodiment, the A / D converter 40 binarizes the distortion signal, but the A / D converter 40 may convert the distortion signal into a multistage digital signal. Thereby, a stepwise warning can be performed according to the magnitude of distortion of the optical base 30.

Next, in the present embodiment, the configuration of the legs of the housing will be described in detail. FIG. 7 is a schematic plan view of the projector device fixed to the mounting base, and FIG. 8 is a schematic view of the feet formed on the housing.

A screw hole 24 is formed in the bottom surface 28 of the foot provided on the bottom surface 14 of the housing (see also FIG. 3). As described above, the housing 12 is fixed to the mounting base 20 via the foot portion 26.

Since the foot part 26 of the housing 12 supports the projector 10, it generally has high strength. Therefore, the distortion of the housing 12 can be reduced by fixing the housing 12 and the mounting base 20 via the foot portion 26 rather than directly fixing the housing 12 and the mounting base 20. In order to fix the housing 12 to the mounting base 20 via the foot portions 26, it is preferable that at least three foot portions 26 are formed.

Further, when the mounting base 20 is fixed to the foot portion 26, the convex portion 50 does not contact the mounting base 20 even if the convex portion 50 is formed on the bottom surface 14 of the housing. Therefore, since there is no gap between the mounting base 20 and the bottom surface 28 of the foot, the distortion of the housing 12 is reduced as compared with the case shown in FIG.

Further, it is preferable that the foot part 26 is configured to be extendable, and it is more preferable that the foot part 26 is configured to be able to bend back and forth. In this specification, a direction F in which the projector 10 projects an image is defined as “front”, and a direction B on the opposite side to the front is defined as “rear”.

Referring to FIG. 8, the foot part 26 has an upper part 60, a lower part 62, and a hinge 64. The upper portion 60 and the lower portion 62 are connected by a hinge 64. The hinge 64 extends substantially parallel to the bottom surface 28 of the foot, and the foot 26 can be bent forward and backward with the hinge 64 as a center. The hinge 64 is preferably bendable in several stages.

Also, the tilt adjustment structure described in Patent Document 4 may be adopted. That is, the foot part 26 is connected to a tilt adjusting part 66 provided in the housing 12, and the tilt adjusting part 66 is movable in the height direction H of the projector. Thereby, the length of the foot | leg part 26 can be adjusted.

As described above, the direction in which the image is projected can be controlled by configuring the foot to be bendable and / or extendable.

As shown in FIG. 9, it is preferable that an elastic member 70 for closing the screw hole 24 is detachably attached to the bottom surface 28 of the foot. Rubber can be used as the elastic member 70.

When the projector 10 is attached to the attachment base 20, the elastic member 70 is removed from the foot portion 26 (see FIG. 8). On the other hand, when the projector is placed on a desk, for example, the elastic member 70 is preferably attached to the foot portion 26. Thereby, the vibration of the projector is prevented.

Further, the projector 10 includes a light source, an image forming element, a projection lens, and the like. The light emitted from the light source is converted into an image by the image forming element. The light converted into an image is projected onto a screen, for example, through a projection lens. As the components provided in the housing 12 and their arrangement, those of conventional techniques can be arbitrarily adopted.

The projector 10 may further include a sensor that detects the tilt of the housing 12, for example, a biaxial acceleration sensor. Thereby, the inclination of the housing | casing 12 currently fixed to the attachment base 20 is detectable.

While preferred embodiments of the invention have been presented and described in detail, it should be understood that various changes and modifications can be made without departing from the spirit or scope of the appended claims.

Claims

In a projection display device having a housing that can be fixed to a mounting base,
A projection display device comprising a strain sensor for detecting strain.
An optical base provided inside the housing and on which optical components are mounted;
The projection display device according to claim 1, wherein the distortion sensor detects distortion of the optical base.
The projection display device according to claim 1, wherein the strain sensor is a strain gauge sensor that detects a strain at a position where the strain sensor is attached as a change in electric resistance.
The projection display device according to any one of claims 1 to 3, wherein the casing is configured to be fixed to a lower surface of the mounting base.
5. The projection display device according to claim 1, further comprising a display unit configured to display a result detected by the strain sensor.
Legs that support the casing when the projection display device is stationary are formed on the casing,
The projection display device according to any one of claims 1 to 5, wherein a fixture for fixing the housing to the attachment base is attached to the foot portion.
The fixture is a screw;
The projection display device according to claim 6, wherein a screw hole is formed in a bottom surface of the foot portion.
The projection display device according to claim 7, wherein an elastic member that closes the screw hole is detachably attached to a bottom surface of the foot portion.
9. The unevenness according to claim 1, wherein an unevenness is formed on one surface of the housing that faces the mounting base when the housing is mounted on the mounting base. 10. The projection type display device described.