JPH09322186A - Projection lens mounting device for crt projector television - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the cathode ray tube(CRT) projector television receiver in which a CRT is driven with a same electric circuit even when a screen size or position is changed and excellent image performance is obtained on the screen. SOLUTION: The mount device is provided with a front CRT 16 whose normal lens optical axis 10 is extended onto a normal from a center of screens S1, S2, two tilt CRTs 14, 15 each having a couple of tilt lens optical axes whose start points are cross points between the normal lens optical axis and the screens and which are extended straightforward symmetrically horizontally as being parted from the screens, projection lenses 26 arranged between the screens and each CRT and mount bases 24 used to mount the projection lenses. The projection angle of the tilt lens optical axis with respect to the normal lens optical axis is adjusted by changing the mount angle of each projection lens 26 to each mount base 24 so that the cross points between the screens and the normal lens optical axes are coincident with the tilt lens optical axes regardless of the screen size and position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention shows a color image on a screen of a television set by enlarging and projecting an image of each color from a cathode ray tube (hereinafter referred to as "CRT") on a screen. , A projection lens mounting device used for a CRT projector television.

[0002]

2. Description of the Related Art As shown in FIG. 7, a projection lens mounting device B of a CRT projector TV, which uses three CRTs 50, 51 and 52 of red, green and blue, is used for each CRT5.
The respective red, green and blue images of 0, 51 and 52 are enlarged and projected onto the 46-inch screen S1 by the three projection lenses 56, 57 and 58. Also, in order to balance the height and depth of the television set, although not shown, the screen S1 and each CRT 50,
A plurality of mirror sets are arranged between the projection lenses 56, 57 and 58 for 51 and 52.

As shown in FIG. 7, the CRT 51 for projecting a green image has its lens optical axis 59 aligned with the normal line from the center C1 of the screen S1, while the red and blue images are respectively displayed. The two CRTs 50 and 52 that project are
Inclining those lens optical axes 60 and 61 to the normal side,
The centers of the screens are matched with the center C1 of the screen S1.

However, when the screen size is changed from the screen S1 of 46 inches to the screen S2 of 41 inches, the screen S2 and the projection lenses 56, 57 and 58.
The same couplers 62 and 63 as before the change are used for different screens S2, because the distance between them changes, as shown in FIG.
Although the lens optical axis 59 of T51 coincides, the lens optical axes 60 and 61 of the two red and blue CRTs 50 and 52 do not coincide with the center C2 of the screen S2 as at the center C1 of the screen S1. Will end up.

[0005]

In order to solve such inconsistency of the lens optical axes 59, 60, 61 on the screen S2, conventionally, an electrical correction (offset) is applied to the raster of the CRT 50, 52. By moving the center, the center of the projection screen from the CRTs 50 and 52 is equivalently aligned with the center C2 of the screen S2. However, in order to perform such an operation, two types of CRT drive circuits are required, and when the amount of movement of the raster center is large, the correction balance of the screen changes and a good image on the screen S2 is obtained. There was a problem that performance might not be obtained.

In view of the above problems, the present invention can drive the CRT with the same electric circuit even if the size and position of the screen are changed, and provides good image performance on the screen. An object of the present invention is to provide a projection lens mounting device that can realize a CRT projector television that can be obtained.

[0007]

In order to solve the above problems, the present invention provides one front CRT having a normal lens optical axis extending on a normal line from the center of the screen, and the normal lens optical axis. Two tilted CRTs each having a pair of tilted lens optical axes that start from an intersection with the screen and linearly extend symmetrically with distance from the screen.
A projection lens arranged on the optical axis between the screen and the CRT, and a mount for mounting the projection lens, wherein the projection lens mounting device for a CRT projector TV is arranged on the tilted lens optical axis. The projection angle of the tilted lens optical axis with respect to the normal lens optical axis is adjusted by changing the mounting angle of the projection lens with respect to the mounting base, regardless of the size and position of the screen. The intersection of the linear lens optical axes is made to coincide with the tilted lens optical axis.

According to the projection lens mounting apparatus for a CRT projector TV of the present invention having such a configuration, the tilted lens optical axis is changed by changing the mounting angle of the projection lens arranged on the tilted lens optical axis with respect to the mounting base. Since you can adjust the projection angle that is made with respect to the normal lens optical axis, even if the screen size or position changes, the changed intersection of the new screen and the normal lens optical axis matches the tilted lens optical axis. Can be made. Therefore, the CRT can be driven by the same electric circuit, and at the same time, a CRT projector television can be realized which can obtain good image performance on the screen.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the accompanying drawings. FIG. 1 is a diagram showing an overall configuration of a projection lens mounting device A for a CRT projector TV according to a first embodiment of the present invention.

As shown in the figure, a projection lens mounting device A for a CRT projector TV has a lens optical axis (normal lens optical axis) extending in line with a normal from a center C1 of a screen S1 having a screen size of 46 inches. 10
One CRT (front CR) that has a
T) 16 and a point of intersection of the lens optical axis 10 and the screen S1 (center C1 of the screen S1) as a starting point, and a pair of lens optical axes (tilted lens light) that extend in a linear direction that is symmetrically inclined with distance from the screen S1 Axis) 1
Two CRTs (gradient CRTs) 14 and 15 having red and blue images, respectively, are provided.

On the lens optical axis 10 line of the green CRT 16 extending toward the center C1 of the screen S1, a coupler 17 fixed on a chassis 27 whose upper surface is arranged in parallel with the screen S1, and this coupler 17. The lens mounting plate 18 provided and the projection lens 19 provided on the lens mounting plate 18 are arranged in one row.

On the other hand, on the lens optical axes 12 and 13 of the red and blue CRTs 14 and 15 extending symmetrically toward the center C1 of the respective screens S1, the coupler 22 fixed on the chassis 27 and the coupler 22 are provided. A lens mounting plate 24 fixed to the coupler 22 in an inclined state and a projection lens 26 mounted on the lens mounting plate 24 are arranged in one row. Red and blue CRT1
As shown in FIG. 1, 4 and 15 have the same configuration except that they are symmetrically arranged, and therefore, the same parts are designated by the same reference numerals.

The present embodiment is substantially the same as the chassis 27.
The projection angle β formed by the lens optical axes 12 and 13 with respect to the lens optical axis 10 is changed by changing the mounting angle of the projection lens 26 with respect to the lens mounting plate 24 fixed via the coupler 22.
Even if the screen is changed from the screen S1 (46 inches) having a different size or position to the screen S2 (41 inches) by adjusting 1 and β2, the intersection of the screen S2 and the lens optical axis 10 (screen It is characterized in that the center C2) of S2 is made to coincide with each of the lens optical axes 12 and 13.

That is, in the present embodiment, FIGS.
As shown in FIG. 4, the lens mounting plate 24 having a constant inclination angle with respect to the surface of the chassis 27 is provided with a phase difference of 45 ° in the circumferential direction on the surface thereof, and alternately has four rectangular shapes. Flat mounting pieces 28a, 28b, 28c, 28d and 4
Two rectangular inclined mounting pieces 29a, 29b, 29c, 2
9d are formed. Here, as shown in FIG.
The flat mounting pieces 28a, 28b, 28c, 28d have the same height, and their surfaces are all located on the flat mounting surface M1 (the upper surface of the lens mounting plate 24).

On the other hand, as shown in FIG.
The inclination angles of a, 29b, 29c, and 29d are the same (α), but the inclination attachment piece 29a is the highest and the inclination attachment piece 29a has the highest inclination angle.
c is the lowest, and the inclined mounting pieces 29b and 29d have an intermediate height, and their surfaces are all located on the inclined mounting surface M2. In the present embodiment, the inclined mounting surface M2 is inclined by 1 ° with respect to the flat mounting surface M1. Further, as shown in FIGS. 3 and 4, four lens mounting seats 31 are formed at the base of the cylindrical case portion of the projection lens 26 with a phase difference of 90 ° in the circumferential direction.

At the first lens mounting position shown in FIG. 3, the four lens mounting seats 31 are mounted and fixed on the four flat mounting surfaces 28a, 28b, 28c and 28d, respectively. At this time, the lens mounting plate 24 of the projection lens 26
The mounting angle α with respect to the surface 24a is 0 as shown in FIG.
Is (flat mounting surface M1), and as shown in FIG. 1, the projection angle formed by the lens optical axes 12 and 13 with respect to the lens optical axis 10 is β1. Therefore, as shown in FIG. 1, the lens optical axes 12 and 13 of the red and blue CRTs 14 and 15 coincide with the center C1 of the 46-inch screen S1, that is, the intersection of the screen S1 and the lens optical axis 10. .

However, in the case of the 41-inch screen S2, since the screen S2 is located in front of the screen S1, the projection distance will be different if the projection lens 26 is used as it is. Therefore, as shown in FIG. Axis 12,
13 is off the center C2 of the 41-inch screen S2,
Produces an offset e.

In this embodiment, the projection lens 26 has a 45 ° angle around the lens optical axis, as shown in FIGS.
It is possible to rotate, and by this rotation, at the second lens attachment position as shown in FIG. 4, the four lens attachment seats 3 attached to the base of the cylindrical case portion of the projection lens 26 are mounted.
1 is four inclined mounting surfaces 29a, 29b, 2 respectively
It will be mounted and fixed on 9c and 29d. At this time, as shown in FIG. 5, the mounting angle α of the projection lens 26 is 1 ° (inclined mounting surface M2), and as shown in FIG. 1, the lens optical axes 12 and 13 are relative to the lens optical axis 10. The projection angle is β2.

Therefore, as shown in FIGS. 1 and 5, red,
The lens optical axes 12 and 13 of the blue CRTs 14 and 15 are 46
The lens optical axes 12 and 13 are inclined from the center C1 of the 46-inch screen S1 to the center C2 of the 41-inch screen S2, that is, the screen S2, as compared with the case of the inch-screen S1. It changes so as to coincide with the intersection of the lens optical axis 10. By the way, in FIGS. 3 and 4, reference numeral 33 is a focus adjustment screw screwed to the projection lens 26 from the outside to the inside of the case cylindrical portion, and 34 facilitates rotation of the projection lens 26 and movement in the lens optical axis direction. Therefore, it is a circumferentially inclined guide groove provided on the cylindrical portion of the case.

Incidentally, in the first embodiment described above,
Although the projection lens 26 can take two types of lens attachment positions, three different types of lens attachment pieces 35a to 35d, 36 are provided as in the second embodiment shown in FIG.
By providing a to 36d and 37a to 37d, it is possible to adopt three types of attachment positions with different attachment angles of 0 °, 1 °, and 2 °. In this case, three types of lens mounting pieces 35a to 35d, 36a to 36d, 3
By setting the phase difference of 7a to 37d in the circumferential direction with respect to each other to 30 °, it is possible to realize that three types of mounting positions can be adopted.

[0021]

As described above, according to the present invention, by changing the mounting angle of the projection lens arranged on the optical axis of the tilted lens with respect to the mounting base, the optical axis of the tilted lens with respect to the optical axis of the normal lens is changed. Since the projection angle can be adjusted, the intersection of the changed new screen and the normal lens optical axis can be made to coincide with the tilted lens optical axis even if the screen size or position changes. Therefore, the CRT can be driven by the same electric circuit, and at the same time, a CRT projector television can be realized which can obtain good image performance on the screen.

Therefore, since the same CRT drive circuit can be used for screens having different sizes and positions, the manufacturing cost of the CRT projector TV set can be reduced and the raster center can be electrically connected. Since it is not necessary to move the image, deterioration of the image on the screen can be prevented.

According to the projection lens mounting device for a CRT projector TV set forth in any one of claims 2 to 4, the projection lens on the tilted lens optical axis is rotatable about the lens optical axis, and two types of projection lenses are provided. , Or 3 or more types of rotational positions can be fixed, and 2 or 3 types of projection lens
Since more than one type of mounting angle can be adopted, the mounting angle of the projection lens can be changed simply by rotating the projection lens around the lens optical axis, so that the mounting angle of the projection lens can be adjusted easily, quickly and accurately. You can

[Brief description of drawings]

FIG. 1 is a conceptual configuration explanatory diagram of a projection lens mounting device A for a CRT projector TV according to a first embodiment of the present invention.

FIG. 2 is a plan view of a lens mounting plate 24.

FIG. 3 is a projection lens 26 at a first lens mounting position.
FIG. 3 is an explanatory view of a mounting state of FIG.

FIG. 4 is a projection lens 26 at a second lens mounting position.
FIG. 3 is an explanatory view of a mounting state of FIG.

FIG. 5 is a conceptual explanatory diagram of a lens mounting angle.

FIG. 6 is a plan view of a lens mounting plate 24 showing a second embodiment of the present invention.

FIG. 7 is a conceptual configuration explanatory diagram of a conventional projection lens mounting device B for a CRT projector TV.

[Explanation of symbols]

A: Projector TV projection lens mounting device, S1
... screen (46 inches), C1 ... center of screen S1, S2 ... screen (41 inches), C2 ... center of screen S2, 10 ... lens optical axis, 11 ... green CR
T, 12 ... Lens optical axis, 13 ... Lens optical axis, 14 ... Red CRT, 15 ... Blue CRT, 17 ... Coupler, 18 ... Lens mounting plate, 19 ... Projection lens, 22 ... Coupler, 24
... Lens mounting plate, 24a ... Surface, 26 ... Projection lens, 2
7 ... Chassis, 28a-28d ... Flat mounting piece, 29a-
29d ... Inclined mounting piece, 33 ... Focus adjusting screw, 34 ... Circular direction inclined guide groove, 35a-35d ... Lens mounting piece, 36
a to 36d ... Lens mounting piece, 37a to 37d ... Lens mounting piece, M1 ... Flat mounting surface, M2 ... Inclined mounting surface, α ... Mounting angle, β1 ... Projection angle (at 46 inch screen), β
2 ... Projection angle (41-inch screen)

Claims (4)

[Claims] 1. A front CRT having a normal lens optical axis extending on a normal line from the center of the screen, and left and right symmetrically with respect to the screen starting from an intersection of the normal lens optical axis and the screen. Two tilted CRs each having a pair of linearly extending tilted lens optical axes
A projection lens mounting device for a CRT projector TV, comprising: T, a projection lens arranged on the optical axis between the screen and the CRT, and a mounting base for mounting the projection lens on the tilted lens optical axis. By changing the mounting angle of the projection lens to be mounted with respect to the mounting base, the projection angle of the tilted lens optical axis with respect to the normal lens optical axis is adjusted, and the screen and the screen are adjusted regardless of the size or position of the screen. CRT characterized in that the intersection of the normal lens optical axis is made to coincide with the tilted lens optical axis
Projection lens mounting device for projector TV. 2. A projection lens disposed on the tilted lens optical axis is rotatable about the lens optical axis, and the projection lens can be fixed at a plurality of types of rotational positions. The projection lens mounting device for a CRT projector TV according to claim 1, wherein a plurality of different mounting angles can be adopted. 3. The CRT projector according to claim 2, wherein the projection lens can be fixed at two types of rotational positions, and the projection lens can take two types of different mounting angles depending on the rotational position. Projection lens mounting device for TV. 4. The projection lens can be fixed at three or more kinds of rotational positions, and the projection lens can be fixed at three or more rotational positions.
The projection lens mounting device for a CRT projector TV according to claim 2, wherein different mounting angles of more than one type can be adopted.