JP4081770B2 - projector - Google Patents

Description

  The present invention relates to a projector, and more particularly to a projector including a lens cap that is attached to and detached from a light projection port of a lens tube.

  Conventionally, some lens caps that can be attached to and detached from the lens barrel of a projector are handled only by the lens cap. However, this is a great deal of attention and interest in managing the lens cap removed from the lens barrel. If you did not pay, there was a risk of losing. Also, even if the lens cap is connected to the projector with a string, and the lens cap is removed from the lens tube when the projector is in use, the lens cap remains connected to the lens tube with the string to prevent its loss. Some of them were made.

  On the other hand, in order to prevent the lens cap from being lost, there has been known a technique in which the lens cap is connected to a ring having a screw attached to the lens hood with a hinge made of a bending resistant plastic (see Patent Document 1). ). It has also been conventionally known that a lens cap is connected to a mounting member attached to a lens barrel of a camera via a mechanical hinge or a resin hinge (see Patent Document 2, Patent Document 3, and Patent Document 4). .

Further, the projector housing is divided into a first housing provided with a projection lens and a second housing connected to the first housing via a hinge part so as to be opened and closed, and the projection lens is provided in the second housing. It has been conventionally known that the projection lens is accommodated in the projection lens accommodation recess by closing the second housing by providing the accommodation recess (see Patent Document 5).
Japanese Utility Model Publication No. 57-14128 Japanese Patent Laid-Open No. 3-157635 Japanese Utility Model Publication No. 58-71725 JP 2003-43555 A JP 2003-84367 A

  However, although the above-mentioned conventional example in which the lens cap is connected to the projector with a string can achieve the temporary purpose of preventing the loss of the lens cap, the projector is lifted up slightly to achieve a stable installation surface. When performing the installation work, etc., the lens cap that is removed from the lens tube and connected to the projector with a string is often sandwiched between the installation surface, which is very troublesome.

  Therefore, the present invention prevents the lens cap from being lost by installing the lens cap so as not to be separated from the projector, and further facilitates the handling of the lens cap when installing the projector on the installation surface. It is an object of the present invention to provide a projector that not only can eliminate the annoyance that the lens cap becomes obstructed, but also can make the lens cap compact by utilizing the optical characteristics of the projector.

  The projector according to the present invention is a projector having a lens cap for opening and closing the light projection opening of the lens tube, and the projector has an effective light projection area on the upper side and a non-use on the lower side. A reflection type projector that is vertically divided into two areas, wherein at least part of a non-use area of the light projection opening of the lens tube is covered with a shielding part, and the effective light projection is formed on an upper edge of the shielding part The lens cap that opens and closes the region or the effective light projection region and the remaining portion of the non-use region is connected through a resin hinge, and the lens cap is integrated with the lens together with the lens tube, the shielding portion, and the resin hinge. Molded.

  According to the present invention, even if the lens cap is not connected to the projector with a string, the lens cap is always handled together with the projector without being separated from the projector, so there is no room for the lens cap to be lost. The lens cap can be opened and closed without inconvenience by the action of the resin hinge. Further, it is possible to reduce the number of parts and reduce the cost by eliminating the trouble of separately forming the lens cap.

  There is a DLP (digital light processing: reflection type) projector as a projector in which the light projection opening of the lens tube is divided into two upper and lower parts in an upper effective light projecting area and a lower non-use area. In this DLP projector, since the lower section of the projection opening of the lens cylinder is an unused area, even if the lower section is covered with a shielding part, there is no adverse effect on the projection performance. Therefore, by configuring as in the present invention, the lens cap can be made compact, and the opening / closing operation thereof can be easily performed.

  According to the present invention in which the lens cap is formed integrally with the lens barrel of the projector, since the lens cap is mounted on the projector so as not to be separated from the projector, the lens cap is reliably prevented from being lost. The In addition, there is no room for the lens cap to be hung from the projector with a string, making it easy to handle the lens cap when installing the projector on the installation surface, and the lens cap becoming annoying and annoying Will not occur. Therefore, the user does not have the trouble of managing the lens cap removed from the lens tube, and the trouble of disturbing the lens cap when installing the projector on the installation surface is eliminated.

  Since the shielding part and the resin hinge are arranged in the unused area of the light projection opening of the lens barrel, there are advantages that the lens cap can be made compact and the opening / closing operation can be facilitated by utilizing the optical characteristics of the projector.

FIG. 1 shows a projector according to an embodiment of the present invention, in which (A) and (C) are side views of the main part, and (B) and (D) are front views of the main part. Also, FIG. 2 (A) (B) is an explanatory view showing the optical properties of the DLP projector (reflective projector).

FIG. 2A is a side view of the main part of the DLP projector, where 1 is a housing, 2 is a lens cylinder, and a lens (not shown) is attached to the lens cylinder 2. In this DLP projector, due to the structural reason of the optical system housed in the housing 1, the light projection port 21 of the lens tube 2 is connected to the upper effective light projection area Z1 and the lower side as shown in FIG. There are two upper and lower sections in the use area Z2. In other words, the lens attached to the lens tube 2 is divided into an upper section used for projection and a lower section not used for projection. Generally, the height of the non-use area Z2 is projected. The diameter of the mouth 21 is 1/3 to 1/2. As indicated by the arrow P, the optical axis irradiated from the light projection port 21 of the lens barrel 2 is inclined upward by θ with respect to the horizontal axis.

  In the projector of this embodiment, by utilizing the fact that the light projection port 21 of the lens barrel 2 is divided into two parts, the upper effective light projecting area Z1 and the lower non-use area Z2, as described above. A lens cap 3 for opening and closing the light projection port 21 of the lens tube 2 is provided. That is, as shown in FIG. 1, a part or the whole of the unused area Z2 of the light projection port 21 of the lens tube 2 is covered with a shielding portion 22 integrally molded with resin together with the lens tube 2, and the shielding portion. The lens cap 3 is integrally formed with the resin hinge 4 formed over the entire length of the straight upper end edge of the resin 22, so that the lens cap 3 is connected to the shielding portion 22 via the resin hinge 4. . The lens cap 3 is provided with an arc-shaped fitting piece 31 that is fitted to and detached from the lens tube 2, and the resin hinge 4 is extended as shown in FIGS. 1C and 1D to attach the fitting piece 31 to the lens. By fitting the tube 2 outside, the effective light projection area Z1 of the light projection port 21 is closed. Also, as shown in FIGS. 1A and 1B, the fitting piece 31 is removed from the lens tube 2 and the resin hinge 4 is bent, so that the effective light projecting area Z1 of the light projecting opening 21 is opened. A projected image can be projected from Z1.

  According to the projector of this embodiment, since the lens cap 3 is integrally formed with resin together with the shielding portion 22 and the resin hinge 4 on the lens barrel 2 of the projector, there is no need to handle the lens cap 3 alone. Since the lens cap 3 is not separated from the projector, a situation in which the lens cap 3 is lost cannot occur. Further, when the projector is installed on the installation surface, it is impossible for the lens cap 3 to be sandwiched between the installation surface and the projector, so that the lens cap is not obstructed when the projector is installed.

  Furthermore, since the lens cap 3 only needs to have a size that can open and close only the upper section of the light projection port 21 of the lens tube 2, that is, the effective light projection region Z1, the lens cap 3 is large enough to open and close the light projection port 21 as a whole. There is an advantage that it is more compact than the above, and its opening and closing operation is easy.

(A) is the side view of the principal part in the state which opened the lens cap in the projector which concerns on embodiment of this invention, (B) is a front view of (A), (C) is the state of closing the same The side view of a principal part and (D) are front views of (C). (A) is explanatory drawing which showed the optical characteristic of the DLP projector (reflection type projector), (B) is a front view for demonstrating the optical characteristic.

Explanation of symbols

2 Lens barrel 3 Lens cap 4 Resin hinge 21 Light exit 22 Shielding part Z1 Effective light projection area Z2 Non-use area

Claims (1)

In a projector equipped with a lens cap for opening and closing the projection opening of the lens tube,
The projector is a reflective projector in which the light projection port of the lens tube is divided into two upper and lower parts in an upper effective light projecting area and a lower non-use area.
At least a part of the non-use area of the light projection opening of the lens tube is covered with a shielding part, and the effective light projecting area or the effective light projecting area and the remaining part of the non-use area are opened and closed at the upper edge of the shielding part. A projector characterized in that the lens cap is provided continuously through a resin hinge, and the lens cap is integrally formed of resin together with the lens tube, the shielding portion, and the resin hinge.

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