JPH08262395A - Screening device for movable lens in optical instrument - Google Patents

Abstract

PURPOSE: To provide a screening device for a movable lens in an optical instrument whose assembly an-hours are reduced and which is excellent in outside appearance. CONSTITUTION: In the optical instrument where a lens device 3 is arranged to be moved in a transverse axis direction with respect the optical axis; a cylindrical cover 5 being large enough to allow the lens device 3 to move is fixed in the instrument body, and a screen board 7 is arranged so as to slide in the transverse axis direction with respect to the cover 5, then a through-hole 8 through which the lens device 3 passes is formed in the screen board.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blind device in an optical device such as a liquid crystal projector for preventing the inside of the device from being seen from around the lens when the movable lens device moves.

[0002]

2. Description of the Related Art FIG. 2 shows a part of a liquid crystal projector. A lens device 23 is movably arranged back and forth in an oval window 22 provided in a front panel 21, and the lens device 23 is raised and lowered in the window 22. Is ready to go.

In this case, since the window 22 has an oval shape, the interior of the device can be seen from around the lens device 23 when the lens device 23 moves up and down. Is provided.

The conventional blinding means 24 includes a circular ring member 25 to be fitted on the lens device 23, an oval ring member 26 fitted to the window 22, and a tubular expansion and contraction made of cloth stretched between the ring members. The ring members 25, 26 are made of synthetic resin, and the tubular elastic body 27 is formed into a substantially tubular shape by stitching cloth with stitches 27a.
The opening ends are fixed to the ring members 25 and 26, respectively, the circular ring member 25 is covered on the lens device 23, the oval ring member 26 is fitted in the window 22, and each is fixed by a screw 28.

[0005]

However, in the conventional blindfold means, a considerable number of man-hours are required for assembling, such as sewing the tubular telescopic body 27 and attaching it to the ring member, and
As the lens device 23 was moved up and down, the cloth of the tubular elastic body 27 was wrinkled, which was not preferable in appearance.

An object of the present invention is to solve the above-mentioned drawbacks of the conventional blindfolding means, to provide a blinding device for a movable lens in an optical apparatus which has a small number of assembling steps and is excellent in appearance.

[0007]

A blinding device for a movable lens in an optical apparatus according to the present invention is an optical apparatus such as a projection apparatus in which a lens device is arranged so as to be movable in an axial direction with respect to an optical axis. A tubular cover having a size that allows the device to move is fixed to the main body of the device, and a blind plate provided with a through hole through which the lens device penetrates so that the cover plate can be slid in the intersecting axis direction with respect to the cover. It is arranged.

The blind plate slides along a guide groove formed in the cover. Further, a blind sheet is attached to the side edge portion of the blind plate, particularly to the upper edge to cover the upper void when the blind plate descends.

[0009]

The blind plate moves up and down as the lens device moves up and down to prevent the inside of the set from being seen from around the lens device. Further, with respect to the front and rear movement of the lens device, the lens device moves while making contact with the inside of the hole of the blindfold plate, and the blindfold plate does not move. The upper gap when the blindfold plate descends is covered with a blindfold sheet.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an exploded perspective view showing an example in which a movable lens blinding device in an optical apparatus according to the present invention is applied to a liquid crystal projector. In the figure, 1 is a front panel, 2 is a vertically long rectangular window formed in the front panel 1, 3
Is a lens device that moves back and forth in the direction of arrow F1 and also moves up and down in the direction of arrow F2.

Reference numeral 4 denotes a blinding device, which is a rectangular cylindrical cover 5 having a height that allows the lens device 3 to move up and down, and the lens device 3 that allows the lens device 3 to move forward and backward.
And a blind plate 7 provided with a through hole 8 through which
Both the cover 5 and the blind plate 7 are made of synthetic resin.

The cover 5 is arranged so as to correspond to the square window 2 and is fixed to the main body of the device by a screw 11 via a mounting portion 5a. A blind plate 7 is vertically installed near the rear opening of the cover 5. It is adapted to move up and down along the groove 6. Reference numeral 9 is a notch formed in the lower part of both side edges of the blindfold plate 7, and the upper end edge thereof engages with the abutting portion provided at the lower end of the guide groove 6 to serve as a lower limit lowering stopper of the blindfold plate 7. It was made to become.

Reference numeral 10 denotes a blind sheet made of a flexible material attached to the upper edge of the blind plate 7 for covering an upper void formed between the blind plate 7 and the case 12 when the blind plate 7 descends. , When assembled, it is bent back and assembled. When assembled, the guide groove 6 of the cover 5
The blindfold plate 7 is inserted into the blindfold plate 7, and the lens device 3 is inserted into the through hole 8 of the blindfold plate 7.

In the above embodiment, the blindfold sheet 10 is attached to the upper edge of the blindfold plate 7 for the convenience of the height of the main body of the device, but the height position is such that the inside cannot be seen even if the blindfold plate 7 descends. As long as they are related, the blind sheet 10 is not necessary, and this makes it possible to reduce the number of parts and man-hours. Also,
In the embodiment, the liquid crystal projector has been described as an example, but it is needless to say that the lens device can be applied to a blindfold device of another optical device in which the lens device can move vertically or horizontally.

[0015]

According to the blind device for a movable lens in the optical apparatus of the present invention, the optical apparatus such as a projection apparatus in which the lens apparatus is arranged so as to be movable in the direction intersecting the optical axis is installed in the main body of the apparatus. A cylindrical cover that is fixed and has a size that allows the lens device to move, and is arranged so as to be slidable in the intersecting axis direction with respect to the cover,
The lens device is composed of a blind plate having a through hole that penetrates the lens device, so that the structure is simple, and, for example, the cover and the blind plate can be molded of synthetic resin, which makes the appearance beautiful. It becomes possible. Further, since the entire device is of a fitting type, it is easy to assemble and the number of assembling steps can be reduced.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an example in which a blind lens device for a movable lens in an optical apparatus according to the present invention is applied to a liquid crystal projector.

FIG. 2 is an exploded perspective view showing a blindfold means in a conventional liquid crystal projector.

[Explanation of symbols]

 1 Front Panel 2 Square Window 3 Lens Device 4 Entire Blinding Device 5 Cover 6 Guide Groove 7 Blinding Plate 8 Through Hole 10 Blinding Sheet

Claims (3)

[Claims] 1. In an optical device such as a projection device in which a lens device is arranged so as to be movable in an axis-to-axis direction with respect to an optical axis, the lens device is fixed to the device body and has a size allowing the lens device to move. Movable optical device comprising: a cylindrical cover; and a blind plate arranged so as to be slidable in the intersecting axis direction with respect to the cover and having a through hole through which the lens device penetrates. Lens blindfold device. 2. A blindfold device for a movable lens in an optical apparatus according to claim 1, wherein a blindfold sheet is attached to a side edge portion of the blindfold plate. 3. The blindfold device for a movable lens in an optical apparatus according to claim 1, wherein the blindfold plate is configured to slide along a guide groove provided in the cover.