JP2949916B2 - projector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projector for projecting a projected image on a screen.

[0002]

2. Description of the Related Art Generally, as this type of projector, as shown in FIG.
A projection having three CRTs a to c for separately projecting images separated into three color elements, and three lenses e to g provided in front of the CRTs a to c and projecting an image on a screen d. One having units A to C is widely known.

In such a projector, the projection axes of the projection units A to C are inclined with respect to each other so that the images from the cathode ray tubes a to c coincide at a certain point on the screen d.

[0004] In this type of projector, screen size, with the change of the projection system such as a projection distance or projection angle, since the launch angle lens convergence angle theta ₁ is changed, the horizontal CRT a~c a tilt angle theta ₂ to change the vertical tilt angle it is necessary to adjust the focus of the focus and screen around the screen center.

Further, by filling a cooling liquid (not shown) for optical coupling between the cathode ray tubes a to c and the lenses e to g, the light emitted from the cathode ray tubes a to c returns to the fluorescent screen. To prevent the contrast of the projected image from lowering.

[0006] For this reason, a projector has conventionally been disclosed in Japanese Utility Model Laid-Open Publication No. 1-115145 as a "projection tube of a projection type television apparatus", and is configured as shown in FIG. Referring to FIG. 1, reference numeral 1 denotes a cathode ray tube having an annular spacer 2; 3, a lens provided in front of the cathode ray tube 1 and having an annular spacer 4; 3 is an annular rubber tube as a coupler interposed between the spacer 4 of the CRT 3 and the spacer 2 of the cathode ray tube 1. A liquid 6 that optically couples the cathode ray tube 1 and the lens 3 is provided in the rubber tube 5 and the spacers 2 and 4.
Is enclosed. Reference numeral 7 denotes an adjusting screw for adjusting the tilt angle of the cathode ray tube 1. Reference numeral 8 denotes a first O-ring interposed between the cathode ray tube 1 and the spacer 2, and reference numeral 9 denotes a second O-ring interposed between the lens 3 and the spacer 4.

In the projector configured as described above, the rubber tube 5 can be deformed by the adjusting screw 7 to adjust the tilt angle of the CRT 1.

[0008]

However, in the conventional projector, the adjustment of the tilt angle of the cathode-ray tube 1 is performed by simply deforming the rubber tube 5, and therefore, the tilt angle accompanying the change of the projection system is adjusted. The optical reference point fluctuated with each adjustment. As a result, it is difficult to perform the mark adjustment, and there is an inconvenience that the reliability of the focus adjustment around the screen is reduced.

The present invention has been made in view of such circumstances, and can adjust the tilt angle of the projection tube.
Accordingly, it is an object of the present invention to provide a projector capable of improving the reliability in focus adjustment.

[0010]

A projector according to the present invention includes a first spacer for holding a projection tube, and a second spacer movably provided in front of the first spacer for holding a lens. An adjusting member for rotatably supporting the second spacer is rotatably provided near the first spacer, and the adjusting member and the second spacer are respectively rotated about axes extending in directions perpendicular to each other. It is constituted by a rotating body that rotates.

[0011]

According to the present invention, the adjustment member and the second spacer can be rotated around an axis passing through the optical reference point when adjusting the tilt angle of the projection tube accompanying the change of the projection system.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of the present invention will be described below in detail with reference to the embodiments shown in the drawings.

1 and 2 are a perspective view and a sectional view showing a projector according to the present invention, and FIG. 3 is a perspective view showing a coupler according to the present invention. In FIG.
Reference numeral 1 denotes a first spacer for holding a cathode ray tube (hereinafter, referred to as “CRT”), and a through hole 1 that is opened on both front and rear end surfaces.
2a and annular grooves 12b and 12c are provided on both sides of the through hole 12a. A frame-shaped positioning projection 13 is provided on the periphery of the opening of the CRT-side annular groove 12b of the two annular grooves 12b and 12c of the first spacer 11, and a projection tube is provided in the positioning projection 13. CRT 14 is mounted.

Reference numeral 15 denotes a second spacer for holding a lens having a stepped through hole 15a opened at both ends of the front and back at the center thereof. The second spacer 15 is movably provided in front of the first spacer 11. At the upper end edge of the second spacer 15, a hook-shaped holding piece 16 composed of a horizontal portion 16a protruding forward and a vertical portion 16b connected to the horizontal portion 16a and protruding upward is integrally provided. The second spacer 15 has a stepped surface on the lens side of the through hole 15a and a CR.
Annular grooves 15b and 15c are provided on the periphery of the T-side opening. A lens assembly 17 having a plurality of lenses 17a to 17d is mounted on the lens-side end surface of the second spacer 15.

Reference numeral 18 denotes a first O-ring as a sealing member, which is mounted in the annular groove 12b of the two annular grooves 12b and 12c, and is provided with the CRT 14 and the first spacer 1.
1 is interposed.

Reference numeral 19 denotes a back focus length (BF
L) A first screw for adjustment is rotatably provided at the four corners of the first spacer 11, and is configured to be able to adjust a forward / backward moving stroke of a variable frame for BFL adjustment described later. I have. Reference numeral 20 denotes a ring for restricting the first screw 19 from moving in the axial direction.

Reference numeral 21 denotes a second O-ring as a sealing member, which is mounted in the annular groove 15b of the two annular grooves 15b and 15c, and is interposed between the lens 17a and the second spacer 15. .

Reference numeral 22 denotes a bellows as a coupler, which is formed of a cylindrical bellows made of an iron-based metal material such as stainless steel, which has a biasing force in the axial direction, between the first spacer 11 and the second spacer 15. The CRT 14 is configured to be able to change the tilt angle of the CRT 14. Annular bodies 23 and 24 as flanges each having a plurality of mounting holes 23a and 24a arranged in parallel in the circumferential direction are welded to both ends of the bellows 22, respectively. The bellows 22 includes the CRT
Liquid 2 for optically coupling 14 and lens assembly 17
5 is enclosed.

Reference numeral 26 denotes a third O-ring as a sealing member, which is a CRT-side end face of the annular body 23 and the through-hole 12a.
And is mounted in the annular groove 12c.

Reference numeral 27 denotes a fourth O-ring as a sealing member.
5a is interposed between the peripheral edge of the opening on the CRT side and mounted in the annular groove 15c.

Numeral 28 denotes a variable frame for adjusting the BFL, which is provided around the bellows 22 so as to be able to advance and retreat, and is screwed to the tip of the first screw 19. At the upper and lower edges of the movable frame 28, the second spacer 15
The two holding pieces 28a and 28b opposed to the upper and lower end surfaces of are respectively provided integrally.

Reference numeral 29 denotes a frame-shaped adjusting member,
First pins 30, 31 extending vertically to 8a, 28b
It is provided rotatably via. This adjusting member 29
, The second spacer 15 is pivotably supported via second pins 32 and 33 extending in the horizontal direction.

Here, the first pins 30 and 31 are fixed to the movable frame 28, and the second pins 32 and 33 are fixed to the adjusting member 29. And these first two
The pins 30, 31 and both the second pins 32, 33 are set at positions where the intersections of the respective axes coincide with the optical reference points.

Reference numeral 34 denotes a second screw for adjusting the angle in the vertical direction.
The distal end portion is screwed to the vertical portion 16b of the holding piece 16 with the front end portion abutting on the front end surface of the adjusting member 29.

Reference numeral 35 denotes a third screw for adjusting a horizontal angle.
At the upper right side of the adjustment member 29, the tip is
8 is screwed into contact with the front end face.

Reference numerals A ₁ , A ₂ and B ₁ , B ₂ in the figure denote rotation directions of the second spacer 15 by adjusting the second screw 34 and rotation of the adjusting member 29 by adjusting the third screw 35, respectively. Indicates the direction.

In the projector configured as described above, the tilt angle of the CRT 14 is adjusted by moving the second screw 34 or the third screw 35 forward and backward.

[0028] That is, when advancing the second screw 34 on the CRT side, since the second spacer 15 is rotated in the direction indicated by the arrow A ₁ in FIG. 1 the second pin 32, 33 as a rotation axis,
The bellows 22 partially extends. At this time, the lens assembly 17 swings in the same direction as the rotation direction of the second spacer 15, and the optical axis at the initial position is inclined clockwise in FIG.

Further, retracting the second screw 34 on the lens side, the second spacer 15 is rotated in the direction indicated by arrow A ₂ in Fig. 1 the second pin 32, 33 as a rotation shaft, the bellows 22 Partially shrinks. At this time, the lens assembly 17
Swings in the same direction as the rotation direction of the second spacer 15, and the optical axis at the initial position is inclined counterclockwise in FIG.

On the other hand, it is advanced a third screw 35 on the CRT side, since the adjusting member 29 is rotated in the direction indicated by arrow B ₁ in FIG. 1 a first pin 30, 31 as a rotation shaft, the bellows 22 is Partially elongate. At this time, the lens assembly 17 swings in the same direction as the rotation direction of the adjustment member 29, and the optical axis at the initial position is inclined clockwise (in plan view).

Further, when retracting the third screw 35 on the lens side, since the adjusting member 29 is rotated in the direction indicated by the arrow B ₂ in FIG. 1 a first pin 30, 31 as a rotation shaft, the bellows 22 is Some shrink. At this time, the lens assembly 17 swings in the same direction as the rotation direction of the adjustment member 29, and the optical axis at the initial position is tilted counterclockwise (in plan view).

The dimensional adjustment between the CRT 14 and the lens assembly 17 is performed as follows.

That is, when the first screw 19 is advanced to the lens side, the moving frame 28 moves to the CRT side, so that the second spacer 15 moves in the same direction as this moving direction.
At this time, the entire bellows 22 contracts in the axial direction and C
The dimension between the RT 14 and the lens assembly 17 is reduced.

On the other hand, when the first screw 19 is retracted to the CRT side, the moving frame 28 moves to the lens side, so that the second spacer 15 moves in the same direction as this moving direction. At this time, the entire bellows 22 extends in the axial direction and the CRT
The dimension between 14 and the lens assembly 17 is increased.

Therefore, in the present embodiment, the adjustment member 29 and the second spacer 15 can be rotated around the axis passing through the optical reference point when the tilt angle of the CRT 14 is adjusted according to the change of the projection system. The optical reference point does not change every time the tilt angle of the CRT 14 is adjusted, and fine adjustment of the tilt angle can be performed. In this case, the optical reference point is the first
It is determined from the intersection of the axis of the pins 30, 31 and the axis of the second pins 32, 33.

In this embodiment, since the amount of deformation of the coupler can be set to a large amount, the CR
The tilt angle adjustment range of T14 can be expanded.

Further, in this embodiment, the sealing between the first spacer 11 and the annular body 23 can be enhanced by the third O-ring 26, and the sealing between the second spacer 15 and the annular body 24 can be enhanced by the fourth O-ring 27. Can be enhanced.

Further, in this embodiment, since the bellows 22 is formed of an iron-based metal material made of stainless steel, the heat radiation effect of the liquid 25 can be enhanced.

In addition, in this embodiment, since the coupler is formed by a bellows having an urging force in the axial direction, it is possible to prevent the bellows 22 from bending due to gravity.

In this embodiment, the second spacer 15 is pivotally supported by the second pins 32, 33 extending in the horizontal direction, and the adjusting member 29 is pivotally supported by the first pins 30, 31 extending in the vertical direction. Although an example of pivoting by the second spacer 15 has been described, the present invention is not limited to this.
The same effect as that of the embodiment can be obtained by pivotally supporting the adjusting member 29 by a pin extending in the horizontal direction while pivoting the adjusting member 29 by the pin extending in the vertical direction.

[0041]

As described above, according to the present invention, a first spacer for holding a projection tube and a second spacer movably provided in front of the first spacer for holding a lens are provided. An adjusting member for rotatably supporting the second spacer is rotatably provided near the first spacer, and the adjusting member and the second spacer are respectively rotated about axes extending in directions perpendicular to each other. When the tilt angle of the projection tube is adjusted according to the change of the projection system, the adjustment member and the second member are provided around the axis passing through the optical reference point.
The spacer can be rotated.

Therefore, the vertical and horizontal tilt angles can be adjusted without changing the optical reference point every time the tilt angle of the projection tube is adjusted, and the reliability in focus adjustment can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a projector according to the invention.

FIG. 2 is a sectional view showing a projector according to the present invention.

FIG. 3 is a perspective view showing a coupler according to the present invention.

FIG. 4 is a plan view showing an outline of the projector.

FIG. 5 is a sectional view showing a conventional projector.

[Explanation of symbols]

11: First spacer, 14: CRT, 15: Second spacer, 17: Lens assembly, 17a: Lens, 29: Adjusting member, 30, 31: First pins, 32, 33: Second pins.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Showa 60-161313 (JP, U) Japanese Utility Model Showa 64-51385 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03B 21/00 G02B 7/02 H04N 5/74 H04N 9/31

Claims (1)

(57) [Claims] A first spacer for holding a projection tube; and a second spacer movably provided in front of the first spacer to hold a lens, and rotatably pivotally support the second spacer. An adjusting member is rotatably provided near the first spacer, and the adjusting member and the second spacer are each constituted by a rotating body that rotates around an axis extending in a direction perpendicular to each other. Projector.