JP2007240678A - Liquid crystal projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal projector suitably miniaturized by enhancing the housing property of a lens barrel equipped with a projection lens. <P>SOLUTION: The single-plate type liquid crystal projector 10 which guides light from a light source 13 to a liquid crystal panel 11 having video information so as to change into video light and projects the video light to a screen by a projection lens has: a housing 23 in which the light source and the liquid crystal panel are housed; a first moving mechanism 31 which moves a lens barrel 24 equipped with the projection lens in space A from a position in using where the lens barrel 24 projects from the housing 23 to a position where it approaches to the liquid crystal panel 11; and a second moving mechanism 32 which integrally moves the lens barrel 24 and the liquid crystal panel 11 to the rear space B of the liquid crystal panel so as to house the lens barrel in the housing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a single-plate liquid crystal projector provided with one liquid crystal panel.

  The liquid crystal projector includes a single-plate liquid crystal projector (Patent Document 1) provided with one liquid crystal panel, a three-panel liquid crystal projector (Patent Document 2) provided with three liquid crystal panels, and a DMD (Digital Micromirror Device). A DLP type liquid crystal projector provided with the above is known.

  In such a liquid crystal projector, as described in Patent Document 3, a lens barrel provided with a projection lens is retracted so that it can be stored in the case, and is placed in the case when the lens barrel is stored in the case. The one configured to close the provided shutter is disclosed.

JP-A-4-263237 JP 2000-137289 A JP-A-11-64971

  However, in the liquid crystal projector described in Patent Document 3, only the lens barrel is moved and housed in the housing, and other optical systems including the liquid crystal panel are not moved.

  For example, in the case of the three-panel type liquid crystal projector disclosed in Patent Document 1, a dichroic prism that synthesizes monochromatic image lights of red, green, and blue cannot be moved. It is only moved between the cylinder and the dichroic prism. Similarly, in the case of a DLP type liquid crystal projector, the DMD cannot be moved because a large heat dissipation mechanism and an image processing mechanism are in close contact with the DMD. It can only move to DMD.

  As described above, even when the retractable method is adopted, the conventional liquid crystal projector moves the lens barrel only by the retracting and accommodates it in the housing. A liquid crystal projector could not be provided.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid crystal projector capable of realizing a favorable compactness by improving the storage capacity of a lens barrel provided with a projection lens.

  According to the first aspect of the present invention, in the single-plate type liquid crystal projector in which the light from the light source is guided to a liquid crystal panel having image information to be image light, and the image light is projected onto a screen by a projection lens, the light source and A housing that houses the liquid crystal panel; a first moving mechanism that allows a lens barrel including the projection lens to move from a position in use protruding from the housing to a position approaching the liquid crystal panel; and And a second moving mechanism that moves the lens barrel and the liquid crystal panel integrally to the rear of the liquid crystal panel so that the lens barrel can be housed in the housing.

  According to a second aspect of the present invention, in the first aspect of the invention, the second moving mechanism is configured to rotate the lens barrel and the liquid crystal panel while linearly moving the liquid crystal panel rearward. It is a feature.

  According to a third aspect of the present invention, in the second aspect of the invention, the second moving mechanism rotates the lens barrel and the liquid crystal panel by approximately 90 degrees.

  According to the first aspect of the present invention, the first moving mechanism can move the lens barrel from the position in use protruding from the housing to the position approaching the liquid crystal panel, and the second moving mechanism includes the lens barrel and The liquid crystal panel is moved integrally behind the liquid crystal panel so that the lens barrel can be housed in the housing. For this reason, since the space between the lens barrel and the liquid crystal panel and the space behind the liquid crystal panel can be used as a storage space for the lens barrel, the storage performance of the lens barrel can be improved. As a result, a compact liquid crystal projector having no protrusion when not in use can be provided.

  According to the second or third aspect of the invention, since the lens barrel and the liquid crystal panel are rotated and housed in the housing by the second moving mechanism, the projection lens in the lens barrel is not exposed in the housing. Since it is hidden, damage to the projection lens can be reliably prevented when the liquid crystal projector is not used.

The best mode for carrying out the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing the principle in one embodiment of a liquid crystal projector according to the present invention. FIG. 2 is a plan view showing the lens barrel storing operation of the liquid crystal projector of FIG. FIG. 3 is a plan view showing a continuation of the lens barrel storing operation of FIG.

  The liquid crystal projector 10 shown in FIG. 1 is a single plate type, and projects an image displayed on one liquid crystal panel 11 onto a screen 12. That is, light emitted from the light source 13 is collected by the condenser lens 14 and is incident on the translucent liquid crystal panel 11. The liquid crystal panel 11 has image information corresponding to an input signal and converts incident light into video light. This image light is incident on the projection lens 15 to be enlarged and projected onto the screen 12. Since such a single-plate liquid crystal projector 10 requires only one optical system, there is an advantage that the liquid crystal projector 10 can be reduced in size.

  The light source 13 may be a halogen lamp, a metal halide lamp, or the like, but may be an LED (light emitting diode). Examples of the light source 13 employing LEDs include those shown in FIGS. That is, the light source 13 irradiates light emitted from the LED 16 as a light emitter, which includes an LED (light emitting diode) light emitting element (not shown). The LEDs 16 are a red LED 16A that emits red light, a green LED 16B that emits green light, and a blue LED 16C that emits blue light.

  Red light, green light, and blue light respectively emitted from the red LED 16A, green LED 16B, and blue LED 16C are collected by the collimator lens 17 and incident on the dichroic filter 18 to be combined into white light. The white light is collected by the collimating lens 19 and is incident on the indexer 20 (in this embodiment, a light pipe or a light tunnel). The white light incident on the integrator 20 is repeatedly totally reflected in the integrator 20 to improve in-plane uniformity, and is emitted (irradiated) from the emission end face 21 of the integrator 20.

  The liquid crystal projector 10 provided with the light source 13 includes a light source 13, a condenser lens 14, a prism 22 for bending an optical path in a desired direction, a liquid crystal panel 11, and the like housed in a housing 23. The lens barrel 24 having the projection lens 15 is disposed in the housing 23 so as to be able to enter and exit and is configured to be retractable. The housing 24 is configured to be movable between the liquid crystal panel 11 as shown in FIG. 2 by a first moving mechanism 31 described later. Further, the lens barrel 24 and the liquid crystal panel 11 are moved integrally (linear movement) between the liquid crystal panel 11 and the prism 22 behind the liquid crystal panel 11 as shown in FIG. , Rotational movement). The linear movement and rotational movement of the lens barrel 24 and the liquid crystal panel 11 are performed simultaneously or individually.

Specifically, the first moving mechanism 31 and the second moving mechanism 32 are configured as shown in FIG.
That is, the lens barrel 24 is supported by the bracket 33, and the rotation shaft 35 is fixed to the bulging portion 34 of the bracket 33. The rotation shaft 35 is rotatably passed through the slide plate 36. A slider 37 is fixed to the lower surface of the slide plate 36, and the slider 37 is slidably fitted to a guide rail 38 installed on the bracket 33. The slide plate 36 is formed with a knob 44 extending outside the housing 23. A rotating gear 39 is fixed to the tip of the rotating shaft 35 integrally with the rotating shaft 35, and the rotating gear 39 is configured to be able to mesh with a flat gear 40 installed in the housing 23.

  In addition, a slide shaft 41 is projected from the liquid crystal panel 11. The slide shaft 41 slidably penetrates the bracket 33, and a compression spring 42 is disposed between the tip portion and the bracket 33. The compression spring 42 is configured such that the liquid crystal panel 11 is locked to a stopper 43 implanted in the casing 23, and the knob 44 of the slide plate 36 is locked to the stepped portion 45 of the casing 23. It is held in a compressed state when 10 is used. The stopper 43 is disposed in a groove 46 (FIG. 6) formed in the slide plate 36 as the slide plate 36 moves.

  The bracket 33, the rotating shaft 35, the slide plate 36, the guide rail 38, the slide shaft 41, the compression spring 42, and the stopper 43 mainly constitute the first moving mechanism 31. As shown in FIG. 2, the first moving mechanism 31 moves the lens barrel 24 closest to the liquid crystal panel 11 from the position in use of the liquid crystal projector 10 protruding from the housing 23 (back focus position of the projection lens 15). It is possible to move linearly along the direction of the optical axis O of the projection lens 15 to a position where the projection lens 15 is positioned. Thereby, the space A between the lens barrel 24 and the liquid crystal panel 11 when the liquid crystal projector 10 is used is used as a storage space for the lens barrel 24.

  The bracket 33, the rotation shaft 35, the slide plate 36, the guide rail 38, the rotation gear 39, and the spur gear 40 mainly constitute the second moving mechanism 32. As shown in FIG. 3, the second moving mechanism 32 rotates while moving the closest barrel 24 and the liquid crystal panel 11 linearly in the direction of the optical axis O of the projection lens 15 to the rear of the liquid crystal panel 11. The lens barrel 24 is housed in the housing 23 by rotating approximately 90 degrees around the shaft 35 (FIG. 4). Thereby, the rear space B of the liquid crystal panel 11 between the liquid crystal panel 11 and the prism 22 when the liquid crystal projector 10 is used is used as a storage space for the lens barrel 24.

  Next, operations of the first moving mechanism 31 and the second moving mechanism 32 will be described with reference to FIGS. Here, FIG. 5A is the same drawing as FIG.

  When the lens barrel 24 protrudes from the housing 23 when the liquid crystal projector 10 is used, the slide plate 36 is at the uppermost position in FIG. At this time, the knob 44 of the slide plate 36 is locked to the stepped portion 45 of the housing 23, and the liquid crystal panel 11 is locked to the stopper 43, so that the compression spring 42 is held in a compressed state (FIG. 5A). )).

  In this state, when the knob 44 of the slide plate 36 is removed from the stepped portion 45 of the housing 23, the urging force of the compression spring 42 acts on the bracket 33, and the lens barrel 24 moves downward in FIG. The lens barrel 24 moves linearly along the direction of the optical axis O, and the lens barrel 24 approaches the liquid crystal panel 11 (FIG. 5B).

  When the knob 44 is further moved downward in FIGS. 5 and 6 from the position where the lens barrel 24 is closest to the liquid crystal panel 11, the rotation gear 39 at the tip of the rotation shaft 35 starts to mesh with the flat gear 40, and the lens barrel 24 and The liquid crystal panel 11 is united and begins to rotate around the rotation axis 35 while moving linearly along the optical axis O direction of the projection lens 15 to the rear of the liquid crystal panel 11 (FIG. 6A).

  Then, by further moving the knob 44 downward in FIG. 6, the above-described linear and rotational movement of the lens barrel 24 and the liquid crystal panel 11 further proceeds, and the lens barrel 24 and the liquid crystal panel 11 are rotated by a quarter rotation (approximately 90). And the lens barrel 24 is completely stored in the housing 23 (FIG. 6B).

With the configuration as described above, the following effects (1) to (3) are achieved according to the above embodiment.
(1) The first moving mechanism 31 enables the lens barrel 24 to move from the position in use protruding from the housing 23 to the position closest to the liquid crystal panel 11, and the second moving mechanism 32 includes the lens barrel 24 and the liquid crystal. The panel 11 is moved integrally behind the liquid crystal panel 11 so that the lens barrel 24 can be stored in the housing 23. For this reason, since the space A between the lens barrel 24 and the liquid crystal panel 11 and the rear space B of the liquid crystal panel 11 can be used as a storage space for the lens barrel 24, the storability of the lens barrel 24 can be improved. As a result, it is possible to provide a compact liquid crystal projector 10 having no protrusion when not in use, and the liquid crystal projector 10 can be stored in a pocket of clothes and carried.

  (2) Since the lens barrel 24 and the liquid crystal panel 11 are rotated around the rotation axis 35 by the second moving mechanism 32 and housed in the housing 23, the projection lens 15 in the lens barrel 24 is attached to the housing 23. Since it is not exposed to the outside and is hidden in the housing 23, the projection lens 15 can be reliably prevented from being damaged when the liquid crystal projector 10 is not used without fitting a cap for protecting the projection lens 15 to the lens barrel 24. . Furthermore, since it is not necessary to use a cap for protecting the projection lens 15, there is no risk of the cap being lost.

  (3) Since the storage property of the lens barrel 24 is improved as in the above (1), it is not necessary to design the projection lens 15 in the lens barrel 24 with extremely small size and shortening. Accordingly, the degree of freedom in designing the projection lens 15 and the lens barrel 24 can be improved, and a low refractive lens can be used as the projection lens 15. For these reasons, an increase in the cost of the liquid crystal projector 10 can be suppressed.

  As mentioned above, although this invention was demonstrated based on the said embodiment, this invention is not limited to this. For example, as a mechanical element of the first moving mechanism 31 and the second moving mechanism 32, a guide rail and a rack and pinion may be used.

It is a block diagram which shows the principle in one Embodiment of the liquid crystal projector which concerns on this invention. FIG. 3 is a plan view showing a lens barrel storing operation of the liquid crystal projector of FIG. 1. FIG. 6 is a plan view showing a continuation of the lens barrel storing operation of FIG. 2. 2 and 3 show the first and second moving mechanisms for storing the lens barrel, in which (A) is a plan view, (B) is a left side view, and (C) is a view in the direction of arrow C in FIG. 4 (A). FIG. It is an operation | movement figure which shows the lens barrel accommodation operation | movement by the 1st and 2nd moving mechanism of FIG. FIG. 6 is an operation diagram showing a continuation of FIG. 5.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Liquid crystal projector 11 Liquid crystal panel 12 Screen 13 Light source 15 Projection lens 23 Case 24 Lens barrel 31 1st moving mechanism 32 2nd moving mechanism 35 Rotating shaft A, B Space

Claims (3)

In a single-plate type liquid crystal projector in which light from a light source is guided to a liquid crystal panel having video information to form video light, and this video light is projected onto a screen by a projection lens.
A housing for housing the light source and the liquid crystal panel;
A first moving mechanism that allows the lens barrel including the projection lens to move from a position in use protruding from the housing to a position approaching the liquid crystal panel;
A liquid crystal projector comprising: a second moving mechanism that moves the lens barrel and the liquid crystal panel integrally to the rear of the liquid crystal panel so that the lens barrel can be housed in the housing.   The liquid crystal projector according to claim 1, wherein the second moving mechanism is configured to rotate the lens barrel and the liquid crystal panel while linearly moving the lens barrel and the liquid crystal panel to the rear of the liquid crystal panel.   The liquid crystal projector according to claim 2, wherein the second moving mechanism rotates the lens barrel and the liquid crystal panel by approximately 90 degrees.

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