JPH06105337B2 - Projection tv - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection television having a large screen formed by joining a plurality of Fresnel lenses.

[0002]

2. Description of the Related Art Generally, a projection television is provided with a projector including a CRT unit, a liquid crystal unit and a projection lens in a main body casing, and this projector is provided with one RGB unit and a Fresnel lens and a lenticular lens on the front surface thereof. A screen with a combination of sheets is provided.

Further, Japanese Patent Laid-Open No. 3-73938 discloses a projection television in which four unit Fresnel lenses are joined together, and in the screen, a reinforcing sheet is provided to support the Fresnel lens and fixed, The center of the four Fresnel lenses was also fixed to the reinforcing sheet.

[0004]

Thus, in the projection television in which one Fresnel lens corresponds to one RGB unit in the former case, it is not necessary to center the screen. Further, in the latter, the centering of the Fresnel lens in the lateral arrangement is performed through the reinforcing sheet, which requires the reinforcing sheet, the number of parts increases, and the brightness also decreases. In such a case, if the left and right centers are not aligned, the joints of the Fresnel lens and the wrench killer sheet will appear as joints in the image, making the image ugly.

In view of the above problems, an object of the present invention is to provide a projection television capable of easily aligning the centers of the left and right portions of the screen with respect to the frame of the screen assembly.

[0006]

In a projection television provided with a screen assembly formed by joining together at least two left and right Fresnel lenses on a front surface of a main body casing, the screen assembly includes a Fresnel lens and A frame that defines the periphery of the screen on which a lenticular sheet is superposed, a screen support member attached along the upper side of the screen, and a screen suspension for engaging the screen support member to support the screen on the frame. Consisting of parts,
A first center engaging portion is formed at a position corresponding to a joint between right and left portions of the screen of the screen supporting member, and the first center engaging portion is aligned with the second center engaging portion of the screen hanging member; The first center positioning portion of the screen support member formed corresponding to the second center engaging portion of the screen suspension member is aligned with the second center positioning portion formed at the center of the upper side of the frame.

[0007]

A plurality of Fresnel lenses are spliced together, and a screen support member is attached along the upper side of a screen formed by superposing a lenticular sheet on the spliced Fresnel lens, and a screen suspension member is joined to the screen support member. Attach the screen suspension member to the frame. By aligning the first center engaging portion of the screen supporting member with the second center engaging portion of the screen suspending member, the screen supporting member and the screen suspending member are positioned, and the first center of the screen suspending member is further aligned. By engaging the positioning portion with the second center positioning portion of the frame of the screen assembly, the left and right portions of the screen are suspended in a state corresponding to the center of the frame.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 and 2, the projection television P ₁ of the present invention is composed of right and left independent right and left split units R and L, and the front and rear faces of these left and right split units L and R are connected to each other. A screen assembly S is attached to. The screen assembly S includes a rectangular frame 1, and a Fresnel lens plate 6 formed by laminating four rectangular Fresnel lenses 6a, 6a ... 6a in the rectangular frame 1 as shown in FIG. , A screen 4 formed by bonding the left and right lenticular sheets 5a, 5a together to form a lenticular sheet 5 with a double-sided tape 7 in between.
Is supported in a suspended state. A cross-shaped light-shielding frame 2 is attached to the rear side of the screen 4. The screen 4 is divided into four areas by the light-shielding frame 2, and four CRT units are provided corresponding to each area. The light-shielding frame 2 shields the upper and lower and left and right projection lights so that the projection lights from the CRT units do not intersect with each other to prevent overlapping of images.

In FIG. 3, a positioning hole 3 as a second center positioning portion is formed at the center of the upper side 1a of the screen assembly in the left-right direction. On the other hand, the upper side of the screen 4 is attached to a support bar 8 made of an acrylic rod as a screen support member, and a center recess 9 is provided at the center of the support bar 8 in the longitudinal direction. The center recess 9 corresponds to the seam line l ₁ on the left and right portions of the screen 4. On the other hand, a screen suspension plate 10 is adapted to engage with the support bar 8. The screen suspension plate 10 comprises a vertical plate 11 and a cover plate 12 having a U-shaped cross section formed continuously on the vertical plate 11. It is configured. The vertical plate 11 is provided with screw holes 17, 17 ... 17 at appropriate intervals, and screws 14 are inserted into these screw holes, and the screws 14 are fixed to the inner surface of the upper side 1a of the frame 1 of the screen assembly. . Among the screw holes 17, a screw hole 17a serving as a first center positioning portion located at the center of the vertical plate 11 is aligned with a positioning hole 3 serving as a second center positioning portion of the frame 1. A center protrusion 13 as a second center engaging portion is provided at the center of the upper surface of the cover plate 12 and at a position corresponding to the center screw hole 17a. Engage with the center recess 9.

FIG. 6 shows a state in which the screen 4 is attached to the frame 1. The center bar 9 of the support bar 8 is engaged with the center projection 13 of the screen suspension plate 10 to support the support bar 8. The screen hanging plate 10 and the frame 1 are positioned by positioning the screen hanging plate 10 and engaging the center screw hole 17a with the positioning hole 3 of the upper side 1a of the frame 1 by the screw 14.
Are positioned, and thus the left and right seam lines l ₁ of the screen 4 are positioned at positions corresponding to the positioning holes 3 of the frame 1.

.. 15 are fixed to the inner surfaces of the side plates 1b and 1b of the frame 1, and horizontal screen retainers 16 and 16 are provided on the left and right sides of the lower side 1c of the frame 1. ing. Both of these screen retainers 15 are supported with a space between them so that the left and right sides of the screen 4 are spread by the temperature rise, and the spread is absorbed.
6 supports the screen 4 through a gap so as to absorb the expansion of the screen in the vertical direction due to the temperature rise (FIG. 5).

Therefore, although the screen 4 expands and contracts due to environmental changes such as temperature and humidity as shown in FIG. 5, it is a hanging system, and by fixing the center of its upper side, the image screen can be displayed in good alignment. Be done. That is, if the left and right joint lines l ₁ are aligned with the center of the frame 1 as in the present invention, the left and right center joint lines l ₁ do not move and the joint axis center does not change due to changes in temperature and humidity. Unfortunately, the rays from the left and right projectors are projected without crossing the Fresnel lens and the lenticular lens. However, the horizontal seam line l
₂ will move up and down.

In order to prevent the light projected from the left and right CRT units from overlapping, as shown in FIG. 9, on the overlapping surface of the lenticular sheet 5 of the screen 4 and the Fresnel lens 6, and at the left and right joint lines. point P on l ₁
It suffices that the light ray at a position closer to the left and right joint lines l ₁ than the light ray r reaching The left and right seam lines l
₁ does not move to the left or right depending on changes in temperature and humidity if the center is surely adjusted. Therefore, a light blocking member 41 is attached to the front surface of the vertical frame 40 of the light blocking frame 2.
This prevents overlapping of the light projected from the left and right CRT units. At this time, the front end thickness t of the light shielding member 41 is about 1.5 mm.

As shown in FIG. 5, since the horizontal seam line l ₂ of the screen 4 moves up and down due to variations in processing accuracy or changes in temperature and humidity, the light shielding plate 32 of the horizontal frame 70 is expanded or contracted as the screen 4 expands or contracts. Need to be moved (FIGS. 7 and 8). The horizontal frame 70 has a back plate 30, a screw hole b is provided at the tip of the back plate 30, and the horizontal frame 70 is fixed to the side frame 1b of the frame 1 by a screw (not shown) in the screw hole b. There is. The back plate 30 is provided with elastic holding plates 31, 31 vertically spaced from each other, and a light shielding plate 32 is rotatably held between the elastic holding plates 31, 31. The light shielding plate 32 is provided with a rotary bar 33, both ends of which are projected into the side frame 1b, and a groove 34 is provided on the tip end surface thereof. On the other hand, the side frame 1b is provided with a screw hole 18, and the rotary bar 33 is inserted into the screw hole 18. For example, a screwdriver 19 (FIG. 2) is engaged with a groove 34 of the rotary bar 33 to rotate the rotary bar 33.
The position of the tip of the light shielding plate 32 can be changed by rotating. In this way, the position of the horizontal seam line l ₂ differs depending on the product due to variations in processing accuracy, and the horizontal seam line l ₂ changes depending on the expansion and contraction of the screen 4.
Although it moves up and down, the screen 4 can be formed without any joint by blocking the projection light from other CRT units by adjusting the position of the light shielding plate 32 from the outside accordingly.

In the above embodiment, the horizontal frame 70
The light shielding plate 32 of No. 1 is adjusted from the outside by the driver 19. However, as shown in FIG. 10, the support plate 80 is provided at the left and right end portions on the back side of the screen 4.
A recess 81 is formed in the groove and the recess 81 is made to correspond to the horizontal seam line l ₂ . In the recess 81, the end portion 82a of the light shielding plate 82 is formed.
Are engaged with each other, and the base portion of the light shielding plate 82 is attached to the holding plates 83, 83.
Hold it rotatably inside. When the horizontal seam line l ₂ of the screen 4 moves up and down due to changes in temperature and humidity, the light shielding plate 82 automatically rotates according to the expansion and contraction state of the screen 4, and the tip of the light shielding plate 82 is always 82b will occupy a position aligned with the horizontal seam line l ₂ .

[0016]

Since the present invention is constructed as described above,
The right and left seam lines of the screen can be installed correctly with the center of the frame aligned, and the right and left seam lines do not move left and right due to changes in temperature and humidity. The effect of avoiding the mixing of projection light is achieved, and an image is formed without joints.

[Brief description of drawings]

FIG. 1 is a perspective view of a projection television of the present invention.

FIG. 2 is a perspective view of a screen assembly used in the projection television of the present invention.

FIG. 3 is an exploded perspective view of a screen assembly.

FIG. 4 is an exploded perspective view of a screen.

FIG. 5 is an explanatory diagram of a screen expansion / contraction state.

6 is a sectional view taken along line VI-VI of FIG.

FIG. 7 is a perspective view of a main part of a horizontal frame.

FIG. 8 is an end perspective view of a horizontal frame.

FIG. 9 is a principle explanatory diagram illustrating a principle for preventing images from overlapping.

FIG. 10 is an embodiment explanatory view showing another embodiment of the horizontal frame of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Frame 2 ... Shading frame 3 ... Positioning hole 4 ... Screen 8 ... Support bar 9 ... Center recess 10 ... Screen hanging plate 13 ... Center protrusion 31 ... Holding plate 32 ... Shading plate 33 ... Rotating bar 40 ... Vertical frame 70 … Horizontal frame

Front page continuation (72) Inventor Kanehiro Hagiwara 4-15-5 Omori Nishi, Ota-ku, Tokyo Pioneer Co., Ltd. Omori Plant (72) Inventor Mitsuyoshi Mitake 4-chome Omori Nishi, Ota-ku, Tokyo No. Pioneer Co., Ltd. Omori Factory (56) Reference JP-A-61-194433 (JP, A)

Claims (1)

[Claims] 1. A projection television provided with a screen assembly formed by joining at least two left and right Fresnel lenses on a front surface of a main body casing, wherein the screen assembly includes a Fresnel lens and a lenticular sheet. A frame for defining the periphery of the overlapping screens, a screen support member attached along the upper side of the screen, and a screen suspension member for engaging the screen support member to support the screen on the frame. A first center engaging portion is formed at a position corresponding to a joint between right and left portions of the screen of the screen supporting member, and the first center engaging portion is aligned with the second center engaging portion of the screen suspending member. , A disc formed corresponding to the second center engaging portion of the screen suspension member A projection television characterized in that the first center positioning portion of the lean support member is aligned with the second center positioning portion formed at the center of the upper side of the frame.