JP2000231078A - Video projecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To adjust an illumination area made incident on a light valve element up and down and right and left with simple constitution, to reduce the size of the illumination area and to improve utilization efficiency by arranging a device so that a lens attaching position can be adjusted on a plane perpendicular to an optical axis. SOLUTION: An (x) direction adjusting screw 800 is arranged on a line nearly passing through the optical axis in parallel with a 1st direction ((x) direction) perpendicular to the optical axis in a fitting for adjustment 801. A (y) direction adjusting screw is arranged on the line nearly passing through the optical axis in parallel with a 2nd direction ((Y) direction) perpendicular to the optical axis and perpendicular to the 1st direction in an optical unit cover. An energizing spring is arranged at the lower part of a relay lens B403 so as to energize the lens B403 to a nearly middle direction between a - direction and + direction. By arranging the screw 800 and the (y) direction adjusting screw on a reverse side in a direction where the lens B403 is energized, the position in the (x) direction is decided by the screw 800 and the position in the (y) direction is decided by the (y) direction adjusting screw.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light valve element such as a liquid crystal panel, which modulates a light beam emitted from a light source into a video signal and projects it on a screen. More particularly, the present invention relates to an adjustment mechanism for adjusting a mounting position of a lens disposed in an optical path between a light source and a light valve element.

[0002]

2. Description of the Related Art In an image projection apparatus such as a liquid crystal projector that projects light such as a screen by modulating light emitted from a light source such as a lamp by a light valve element such as a liquid crystal panel, the light from the light source is converted into red, green, blue or the like. As a method of accurately irradiating a light flux from a light source to an image forming area of a light valve element in an optical path having a long optical path length among optical paths of respective colors, an attachment angle of a reflection mirror in the optical path is adjusted. There are methods, and these adjustment mechanisms are disclosed in, for example, Japanese Patent Application Laid-Open No. 10-115803.

[0003]

In the prior art, only the adjustment of the mounting angle in the left-right direction (x direction) is performed, and the adjustment in the vertical direction (y direction) is not taken into consideration. When the size of the illumination area is reduced to improve the image quality, if the light incident on the light valve element is vertically displaced, the image forming area of the light valve element cannot be completely included in the illumination area. Therefore, there is a problem that it is not possible to improve the utilization efficiency by reducing the illumination area in the vertical direction. In addition, when an adjusting mechanism for the vertical mounting angle is added to the reflecting mirror, the adjusting mechanism becomes complicated because the reflecting mirror moves three-dimensionally.

An object of the present invention is to adjust the position of an illumination area incident on a light valve element vertically, horizontally, and with a simple structure,
An object of the present invention is to provide a video projection device in which the size of an illumination area is reduced and the use efficiency is improved.

[0005]

In order to solve the above-mentioned problems, in a video projection apparatus according to the present invention, a lens (relay lens B) disposed in a light path of a color having a long light path length (here, a blue light path). ), An x-direction adjusting screw is arranged in a first direction (x direction) perpendicular to the optical axis, and a y-axis adjusting screw is arranged in a second direction (y direction) perpendicular to the optical axis and perpendicular to the first direction. Is arranged, and an urging spring for urging the lens in a substantially intermediate direction between the x direction and the y direction is arranged. The lens is moved in the x direction by tightening or loosening the x direction adjusting screw, and the y direction adjusting screw is tightened. Alternatively, the lens is moved in the y direction by loosening, so that the lens mounting position can be adjusted on a plane perpendicular to the optical axis.

According to the present invention, since the illumination area of the light incident on the light valve element can be adjusted in the x direction and the y direction by adopting the above configuration, the illumination area is reduced and the utilization efficiency is increased. In this case, the image forming area of the light valve element can be completely covered by the illumination area.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 9 are explanatory diagrams of a video projection device equipped with the present invention.

Prior to the detailed description, a schematic configuration of an image projection apparatus according to an embodiment of the present invention will be described with reference to FIGS.

FIG. 3 is a diagram showing the appearance of a video projection device equipped with the present invention. An optical unit to be described later is housed inside the video projection device 1. In the illustrated image projection device 1, a projection lens unit 502 that is a part of the projection system unit 500 is exposed outside the housing of the image projection device 1, and the projection lens unit 502 causes the projection lens unit 502 to connect to an external screen 122 or the like. An image is projected. An intake port 110 is provided at the front, and an exhaust port 111 is provided at the rear of the side. After taking in outside air from the intake port 110 to cool the inside of the apparatus, the warmed air is discharged from the exhaust port 111 to the outside of the apparatus.

The operation of the apparatus is performed by an external operation signal via the operation button 113 or the remote operation receiving unit 117 on the front. When the device is moved, the handle 122
Use

FIG. 4 shows the appearance of the bottom surface side of the video projector shown in FIG.

An exchange lid 114 for the light source unit 100 is provided on the bottom side of the image projection device 1.
4 is opened and the light source unit 100 is replaced. Also, an adjustment leg A112 and an adjustment leg B for adjusting the angle of the projected image
115 is provided. By adjusting the height of these two legs and adjusting the installation angle of the entire apparatus, the position and inclination of the projected image are adjusted.

An external video signal to the device is supplied to an input terminal A.
118 and the input terminal B120. The power is input to the power connector 119. A remote operation receiver 116 is also provided on the rear side of the apparatus, and operates in the same manner as the remote operation receiver 117 on the front surface shown in FIG.

On the opposite side of the handle 122 shown in FIG. 3, a leg 121 is provided at a position higher than the input terminals 118 and 120. When the handle 122 is held and placed on a floor or the like, the input terminal is provided. 118, 120 are not damaged.

FIG. 5 is an explanatory diagram of the operation state of the video projector 1. In FIG. 5, the positional relationship between the image projected from the image projection apparatus 1 and the image on the lean side is represented by the projection system unit 5.
The light emitted from 00 is directed upward with respect to the horizontal,
A so-called tilt angle is provided. This tilt angle is
It is provided to project an image on the upper screen while the device is installed on a horizontal table such as a desk. In addition, when it is installed above a ceiling or the like, it is possible to display an image on a lower screen or the like below the ceiling by installing it upside down from that in FIG.

FIG. 6 shows an optical configuration inside the image projection device 1.

The light beam emitted from the light source 101 passes through the integrator lens A202, the reflection mirror A407, and the integrator lens B203.

The light beam transmitted through the collimator lens B301 is guided to a dichroic mirror B408. The dichroic mirror B 408 separates into two color components, here red and cyan components, transmits the red component to the reflection mirror D 412 and reflects the cyan component to guide it to the dichroic mirror C 409. Further, the dichroic mirror C409 further separates the incident cyan component into two color components, here a green component and a blue component, reflects the green component to the condenser lens G405, and transmits the blue component to the relay lens A402. Lead each.
In this way, the image is separated into a plurality of color components necessary for color image expression. These optical elements are called a color separation optical system.

The luminous flux of each of the separated color components proceeds to the light valve element means which is in charge of each color component. That is, the red light beam reflected from the reflection mirror D412 passes through the condenser lens R404 to the light valve element R404.
Proceed to 413. The green luminous flux incident on the condenser lens G405 proceeds to the light valve element G414. Also, in the blue light path, similarly to the light paths of other colors, the reflection mirror D410, the reflection mirror F411, the condenser lens B
The light flux passes through 406 and proceeds to the light valve element B 415. Here, since the blue light path has a longer light path length than the other color light paths, the two lenses, the relay lens A402 and the relay lens B403 described above, are arranged to prevent a reduction in light amount due to a difference in light path length.

Light valve elements 413 and 41 for each color component
Images are displayed on the reference numerals 4 and 415 by drive circuit means (not shown), and the incident light of each color component is modulated by the light valve elements 413, 414 and 415 and proceeds to the projection system unit 500. The projection system unit 500 is provided with a prism stage as a synthesizing means for synthesizing the light beams of a plurality of color components.
02 goes outside the device. Thereby, a light valve element for displaying each color is displayed on a screen (not shown),
The composition of the images displayed at 413, 414, and 415 is enlarged and projected as a video.

FIG. 7 shows the configuration of the optical unit 10 inside the video projection device. Although the arrangement of the optical components is shown in the diagram shown in FIG. 6, each optical component is actually supported by the optical unit base 700.

The light source 101 is a light source unit 100
And is attached to the optical unit 10. The light source unit 100 needs to be replaced depending on the use condition, and is detachable from the optical unit 10.

The centrifugal cooling means 130 takes in air from the outside and converts the light valve element 4 in the optical unit 10 into light.
The air is sent to members requiring cooling, such as 13, 414, and 415, for cooling.

The projection system unit 500 includes the optical unit 1
0 is attached to the optical unit base 700 constituting the lower side. That is, the projection system unit 500 is mounted on the optical unit base 700 supporting the optical components.

FIG. 8 shows the optical unit 10 described with reference to FIG.
5 shows a state in which the optical unit cover 701 is attached to the optical unit base 700 constituting the above.

A first cover 160 and a second cover 161 are further attached to the optical unit cover 701, and are disposed above the light valve elements 413, 414, 415.

A light source housing 151 is provided above the light source unit 100, and an axial fan 150 is attached to the light source housing 151 to mainly cool the vicinity of the optical unit 100.

FIG. 9 shows a state in which the optical unit 10 is housed in an outer casing. For the purpose of explanation, the upper part of the housing is cut away.

The optical unit 10 housed in the housing of the video projector 1 takes in the external air taken in from the air inlet 112 by the centrifugal cooling means 130 and mainly uses it for cooling the inside of the optical unit 10. The cooled air is discharged into the housing. On the other hand, an axial fan 150 is provided facing the exhaust port 111, and cools the vicinity of the light source unit 100 and discharges warmed air to the outside of the image projection device 1.
At this time, the air flowing near the light source unit 100 is
The air inside the housing, which is the optical unit 10 described above.
Includes air used to cool the interior. In addition, the axial fan 150 collectively discharges air that has cooled an electric circuit portion such as a power supply and signal processing (not shown) to the outside of the apparatus 1.

Next, the state of light applied to the light valve element will be described. FIG. 10 shows the light valve element 415.
5 shows the relationship between the image forming area 415b and the illumination area 415a. As shown, the light valve element 415
Light valve element 4
The illumination area 415a of the light incident on the optical path 15 is set to be large in consideration of the positioning accuracy of the optical components forming the optical path, the error in the focal length of the lens, and the like. In the blue light path, since the number of optical components to be arranged is large, the positioning accuracy and the focal length of each optical component are large compared to the optical path with a short optical path length. Are accumulated, the deviation of the illumination area of the blue light path is likely to be larger than that of the light paths of other colors. When the displacement is large, the illumination area shown in FIG.
As described above, a position shifted from the image forming area 415b is irradiated. At this time, since light is not irradiated to a part of the image forming area 415b, the image is projected on the screen in a state where the color of the part is lacking, so that a shadow is formed on an edge or color unevenness occurs. If the illumination area is set to be large (415c) so as to irradiate the entire image forming area 415b even if the illumination area 415a is displaced, there arises a problem that the light use efficiency is reduced and the amount of light to be projected is reduced.

Therefore, in the image projection apparatus equipped with the present invention, as shown in FIGS. 1 and 2, the relay lens B403 arranged in the blue light path can be finely adjusted on a plane perpendicular to the optical axis. The position of the illumination area 415a for irradiating the light valve element 415 can be adjusted. The mechanism for adjusting the relay lens B403 will be described in detail.

FIG. 1 is a diagram viewed from above the peripheral portion of the relay lens 2. In FIG. 1, an optical unit cover 701 covers the optical member from above so that the inside can be seen.
Is not shown. FIG. 2 is a sectional view of the relay lens B portion. As shown in FIG. 1, the shape of the relay lens B403 has a surface perpendicular to the optical axis on the outer periphery of the lens, and annular ribs 403a and 403b centered on the optical axis are provided. These ribs 403a and 403b can obtain the same effect regardless of whether they are formed integrally with the lens or formed separately. Furthermore, the optical unit base 700 also has a wall portion 70 formed of a surface perpendicular to the optical axis.
0a, 700b, 700c, 700d, and 700a
700d and 700b and 700b are the same plane. The walls 700a (700d) and 70 of the optical unit base 700
0b (700c), the relay lens B403 is arranged, and the walls 700a (700d) and 700b (700c)
Is between the ribs 403a and 403 of the relay lens B403.
b is set to be slightly larger than the interval between the walls 700a (700d) and 700b (70d).
0c) (on a plane perpendicular to the optical axis). Reference numeral 801 denotes an adjustment bracket, which is fixed to the optical unit base 700 with screws 802. The adjustment metal fitting 801 has an x-direction adjusting screw 80 parallel to a first direction (hereinafter, x direction) perpendicular to the optical axis and substantially passing through the optical axis.
0 is arranged. Also in the optical unit cover, the y-direction adjusting screw 803 is arranged on a straight line that is parallel to a second direction (hereinafter, y direction) perpendicular to the optical axis and perpendicular to the first direction and substantially passes through the optical axis. I have. An urging spring 804 is disposed below the relay lens B, and urges the relay lens B403 in a substantially intermediate direction between the -x direction and the + y direction (the arrow F direction in the figure). By setting the direction of the urging force F by the urging spring 804 as described above, the relay lens B 403 is driven by the component force of the urging force F by -X.
Biasing in one direction, + y direction.
With only 4 it is possible to obtain a biasing force in two directions.

As described above, the relay lens B403 is urged in the -x direction and the + y direction by the urging spring 804, and the x-direction adjusting screw 800, y is located on the opposite side of the direction in which the relay lens B403 is urged. By arranging the direction adjusting screw 803, the position in the x direction can be determined by the x direction adjusting screw 800 and the position in the y direction can be determined by the y direction adjusting screw 803. That is, when the x-direction adjustment screw 800 is rotated in the tightening direction, the x-direction adjustment screw 800 pushes the relay lens B403 and moves in the + x direction. Conversely, when the x-direction adjusting screw 800 is rotated in the loosening direction, the screw is moved in the −x direction by the urging force of the urging spring 804. Similarly, in the y direction, when the y direction adjusting screw 803 is rotated in the tightening direction, the relay lens B403 moves in the −y direction, and when it is rotated in the loosening direction, the relay lens B403 moves in the + y direction.

At this time, in the optical axis direction (Z direction), the wall 700 perpendicular to the optical axis is placed on the optical unit base 700.
a to 700d are provided, and the ribs 403a and 403b on the outer peripheral portion of the relay lens B403 are arranged so that the positioning can be performed accurately.

As described above, when the mounting position of the relay lens B403 is moved in the ± x direction and the ± y direction, the illumination area 415a on the light valve element B415 is also moved by ±.
Move in x direction, ± y direction. Therefore, FIG.
As shown in 415a 'of FIG. 7B, when the irradiation is performed with the image forming area 415b shifted and the entire image forming area 415b is not irradiated, the x-direction adjustment screw 800 and the y-direction adjustment screw 8 are used.
03 by tightening or loosening
By adjusting the mounting position of the 403, the image forming area 415b can be included in the illumination area 415a as shown in FIG.

As described above, by moving the mounting position of the relay lens B403, the light valve element 4
Since the position of the illumination area 415a incident on the light source 15 can be adjusted, the size of the illumination area 415a can be reduced, and the light emitted from the light source 101 can be efficiently projected. In addition, the optical unit base 700 has a wall 700a.
To 700d, and only the x-direction adjustment screw 800, the y-direction adjustment screw 803, and the urging spring 804 need to be arranged, so that lens adjustment can be realized with a simple configuration. Here, the x-direction adjustment screw 800 is an adjustment bracket 80 fixed to the optical unit base 700 by a screw 802.
However, the same effect can be obtained by directly mounting the optical unit base 700. Also, the biasing spring 8
04 is made of a leaf spring, but may be any elastic member such as a coil spring or a sponge.

Next, the adjustment amount (movement amount) of the relay lens B403 will be described. Here, the adjustment amount indicates the movable range of the lens. FIG. 11 is an enlarged explanatory view of the y-direction adjusting screw 803. As the y-direction adjusting screw 803, a flat-pointed screw having a flat portion at the tip end that comes into contact with the relay lens B403 is used, and the amount of movement of the relay lens B403 in the x direction (lateral direction) by the x-direction adjusting screw 800 (not shown). For the adjustment amount, the diameter of the flat portion at the tip of the y-direction adjustment screw 803 is set large. By doing so, the vertex of the relay lens B403 always comes into contact with the flat end of the y-direction adjustment screw 803. Therefore, when the x-direction adjustment screw 800 is tightened or loosened, the relay lens B403 becomes flat with the top of the y-direction adjustment screw 803. And move in parallel. Since the y-direction adjusting screw is arranged perpendicular to the x direction, the flat end of the y-direction adjusting screw 803 is parallel to the x direction, and the moving direction of the relay lens B403 is also parallel to the x direction. Also, the movement of the relay lens B in the y direction is increased by increasing the diameter of the flat portion at the tip of the x direction adjustment screw 800 with respect to the movement amount (adjustment amount) in the y direction as in the x direction.
403 can be moved in parallel with the y direction.

The relay lens B403, the x-direction adjusting screw 800, the y-direction adjusting screw 803, the biasing spring 804
Since the outer peripheral portion of the relay lens B403 is annular and has line contact, the frictional force between these members is small, and the lens can be moved smoothly during adjustment. Furthermore, since the outer peripheral shape of the relay lens B403 is annular around the optical axis, the optical axis does not move even when the relay lens B403 rotates due to friction, vibration, or the like, so that the performance does not change and the reliability does not change. Can be improved.

[0039]

As described above, in a video projection apparatus equipped with the present invention, a lens (relay lens) disposed in an optical path having a long optical path length (blue optical path) among optical paths separated into a plurality of colors. Since B) can be adjusted in the x direction and the y direction, it can be set so that the image forming area of the light valve element is always included in the illumination area of incident light. Therefore, there is no need to set a large illumination area, and the light use efficiency can be improved, so that the brightness of the projected image can be improved. Further, there is no adverse effect such that a shadow is formed on an edge of the projected image or color unevenness occurs.

[Brief description of the drawings]

FIG. 1 is a top view illustrating an adjustment mechanism of a relay lens B according to the present invention.

FIG. 2 is a cross-sectional view of an adjustment mechanism of the relay lens B of the present invention.

FIG. 3 is an external view of a video projection device.

FIG. 4 is an external view of a bottom side of the video projection device.

FIG. 5 is an explanatory diagram of an operation state of the video projection device.

FIG. 6 is an explanatory diagram of an optical configuration inside a video projection device.

FIG. 7 is an explanatory diagram of an optical unit inside the video projection device.

8 is a diagram illustrating a state where an optical unit cover is attached to the configuration of FIG. 7;

FIG. 9 is a diagram illustrating a state where the optical unit is housed in an exterior housing.

FIG. 10 is an explanatory diagram of a state of light applied to a light valve element.

FIG. 11 is an enlarged explanatory view of an adjusting screw portion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Video projection apparatus, 10 ... Optical unit, 100 ... Light source unit, 101 ... Light source, 403 ... Relay lens B, 413, 414, 415 ... Light valve element, 414, 700 ... Optical unit base, 701 ... Optical unit cover , 800: x-direction adjusting screw, 803: y-direction adjusting screw, 804: biasing spring.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Mikio Shiraishi 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Yokohama, Japan Inside the Multimedia Systems Development Division of Hitachi, Ltd. (72) Inventor Kenji Fuse Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa (292) Inventor Fukubashi Abe 292 Yoshidacho, Totsuka-ku, Yokohama-shi, Kanagawa Pref. Hitachi, Ltd. Multimedia System Development Headquarters

Claims (6)

[Claims] 1. A light source, a color separation optical system for separating light emitted from the light source into light beams of a plurality of colors, and a plurality of light beams of each color separated by the color separation optical system, the plurality of light beams corresponding to the respective light beams. Color combining means for modulating the light flux of each color modulated by the light valve element, projecting means for projecting the combined light flux, and an optical unit base for fixedly holding these optical members In the image projection device comprising: a lens is disposed in at least one of the optical paths of the respective light paths until the light flux of each color separated by the color separation optical system is incident on the light valve element corresponding to each light flux, An image projection device, wherein the mounting position of the lens can be adjusted on a plane perpendicular to the optical axis. 2. The apparatus according to claim 1, wherein, among the optical paths of each color separated into a plurality of colors, the mounting position of the lens arranged in the optical path having the longest optical path length can be adjusted on a plane perpendicular to the optical axis. An image projection device, comprising: 3. An adjusting mechanism according to claim 1, wherein said adjusting mechanism for adjusting the mounting position of said lens comprises: a first adjusting screw for moving the lens in a first direction perpendicular to the optical axis; A second adjusting screw for moving the lens in a second direction perpendicular to the first direction and substantially perpendicular to the first direction, and an urging spring for urging the lens in a substantially intermediate direction between the first direction and the second direction. An image projection device comprising: 4. An image projection apparatus according to claim 1, wherein the diameter of the flat portion at the tip of the first adjustment screw is increased with respect to the adjustment amount of the lens in the second direction. 5. An image projection apparatus according to claim 1, wherein the diameter of the flat portion at the tip of the second adjustment screw is increased with respect to the adjustment amount of the lens in the first direction. 6. The lens according to claim 1, 2 or 3, wherein the diameter of the flat portion at the tip of the second adjusting screw is made larger than the adjusting amount of the lens in the first direction, and the adjusting amount of the lens in the second direction is further increased. In contrast, an image projection apparatus characterized in that the diameter of the flat portion at the tip of the first adjustment screw is increased.