JP2003131101A - Optical equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that a satisfactory sealing effect is not obtained due to non-uniformity of a sealing work in a sealing structure around a fastening member for fixing an optical element to a camera main body. SOLUTION: In the optical equipment wherein a base member 2 with the optical element G is mounted is fixed to the equipment body 1 by the fastening member (bolt 14 or nut 5), an elastic sealing member 17 is arranged between the fastening member and the base member or the equipment body while being pressurized and deformed, and the fastening member is provided with an abutting part 14a for deciding the pressure-deformation amount of the elastic sealing member while coming into contact with the base member or the equipment body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical device such as a video camera, and more particularly to an optical device provided with a prism-shaped optical element in the device.

[0002]

2. Description of the Related Art A so-called three-plate type video camera is provided with a color separation optical system which splits light incident from a photographing lens into three primary color lights of red, green and blue and guides them to an image pickup device for each color. ing. In the color separation optical system, a color separation prism having a dichroic film having different reflectance / transmittance depending on the wavelength region of incident light is often used.

FIGS. 3A to 3C show the structure of a color separation optical system provided in the video camera. In addition,
FIG. 3A shows a cross section taken along the line BB in FIG.

In this figure, 1 is a camera body fixed to a video camera housing (not shown), and 2 is a base member to which one side surface of a color separation prism G is adhered. Three
Is a sub-base bonded to the other side surface of the color separation prism G.

Reference numeral 4 denotes a bolt embedded in the recess of the base member 2. The camera body 1 arranged below the recess of the base member 2 and below the recess has a hole through which the bolt 4 penetrates. Has been done.

Reference numeral 5 denotes a nut for fixing the base member 2 to the camera body 1 by being screwed into a portion of the bolt 4 exposed from a hole formed in the camera body 1.

Further, FIG. 4 shows the portion A in FIG. 3 in an enlarged manner. In this figure, reference numeral 6 denotes a blind lid which is arranged in the opening of the base member 2 on the prism side of the concave portion, and the peripheral portion of the blind lid 6 and the peripheral portion of the concave portion are sealed with an adhesive agent AD.

Above the blind cover 6, there is a gap (air gap) formed between a plurality of prisms forming the color separation prism G.

[0009]

With the structure in which the color separation prism G is fixed to the camera body 1 as shown in FIGS. 3 and 4, the sealing work by the adhesive AD during assembly is incomplete, or Adhesive AD when AD hardens
If there is any contraction, the path indicated by the thick line in FIG. 5 (the gap between the hole of the camera body 1 and the nut 5 and the bolt 4 → the gap between the hole and the recess of the base member 2 and the bolt 4 → Through the gap between the blind lid 6 and the recess → the gap between the blind lid 6 and the color separation prism G), moisture in the outside air enters the air gap of the color separation prism G, and the color separation prism G There is a problem that the quality of the captured image is impaired due to clouding or the like.

[0010]

In order to solve the above-mentioned problems, the present invention provides an optical device in which a base member to which an optical element is attached is fixed to a device body using a fastening member (bolt or nut). An elastic seal member is disposed by being pressed and deformed between the fastening member and the base member or the device main body, and an abutting portion which is pressed against the base member or the device main body to determine the pressing deformation amount of the elastic seal member is provided to the fastening member. It is provided.

That is, by pressing the abutting portion of the fastening member against the base member or the main body of the apparatus, the amount of pressing deformation (crushing degree) of the elastic seal member is made constant, and the elastic seal member allows the outside air to enter the periphery of the optical element. Be sure to prevent. This makes it possible to prevent the amount of pressing deformation of the elastic seal member from changing due to variations in work, and it is necessary to seal the space between the blind cover and the base member with an adhesive as in the conventional case. It is also possible to eliminate the blind cover (it is also possible to abolish the blind cover), and it is possible to improve the assembly workability.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) FIG. 1 is an enlarged view of a seal portion of a video camera according to a first embodiment of the present invention. In this embodiment, the same components as those of the conventional video camera shown in FIG. 3 are designated by the same reference numerals as those in FIG.

Reference numeral 1 denotes a camera body fixed to a video camera housing (not shown), and reference numeral 2 denotes a base member to which one side surface of the color separation prism G is adhered. Color separation prism G
Is formed by combining a plurality of prisms and forming a dichroic film on the surface where the prisms face each other.
A slight gap (air gap) is provided between the surfaces where the prisms face each other.

Reference numeral 14 denotes a bolt embedded in the recess of the base member 2, and the bolt 4 is provided on the camera body 1 disposed below and above the recess of the base member 2.
Is formed with a hole portion that penetrates the shaft portion.

Reference numeral 5 is a nut for fixing the base member 2 to the camera body 1 by being screwed into a portion of the bolt 14 exposed from the hole formed in the camera body 1.

Above the concave portion of the base member 2, there is a gap (air gap) formed between a plurality of prisms forming the color separation prism G.

Here, in this embodiment, the bolt 14 on the lower surface of the head of the bolt 14 and the bottom surface of the recess of the base member 2 is used.
A rubber O-ring (elastic sealing member) having a high sealing property is arranged between the shaft portion and the periphery of the hole into which the shaft portion is inserted.

Further, on the lower side of the head of the bolt 14, an abutting surface 14a that abuts the bottom surface of the recess of the base member 2.
Are formed. The dimension between the bottom surface of the head of the bolt 14 and the abutting surface 14a is such that the O-ring 17 is crushed and pressure is applied to the bottom surface of the head of the bolt 14 and the bottom surface of the recess with a pressure required to secure the sealing property. It is set to a size that allows it. That is, the amount of pressing deformation of the O-ring 17 is fixed by the abutment between the abutment surface 14a and the bottom surface of the recess.

As a result, the outside air from the holes of the camera body 1 and the base member 2 is reliably sealed by the O-ring 17, and the outside air can be prevented from entering the air gap of the color separation prism G.

Further, in assembling and holding, the tightening amount of the nut 5 is determined by the abutting surface 14a of the bolt 14 abutting against the bottom surface of the recess, and the pressing deformation amount of the O-ring 17 at this time is always the same. Therefore, variations in work are unlikely to occur and an incomplete sealed state is unlikely to occur.

Moreover, since the O-ring 17 can provide a sufficient sealing effect, it is possible to eliminate the conventional sealing of the blind lid itself or the adhesive of the blind lid, which seals the recess. Therefore, assembling workability can be improved as a whole.

(Second Embodiment) FIG. 2 shows a second embodiment of the present invention.
The seal part in the video camera which is an embodiment is expanded and shown. In this embodiment, the same components as those in the first embodiment are designated by the same reference numerals as those in FIG.

This embodiment is different from the first embodiment in that
It shows an example in which the positions of the bolt and nut are reversed.

In FIG. 2, 24 is a nut (female screw nut) housed in the recess and hole of the base member 2, and 25 is a bolt inserted from the outside into the hole of the camera body 1.

An O-ring 17 is arranged between the lower surface of the head of the nut 24 and the periphery of the hole where the nut 24 is inserted in the bottom surface of the recess of the base member 2.
An abutting surface 24a is formed on the lower side of the head in FIG. The butting surface 24a is butted against the bottom surface of the recess.

The bottom surface of the head of the nut 24 and the abutting surface 24a
The dimension between and is set so that the O-ring 17 can be crushed and pressed against the lower surface of the head portion of the nut 24 and the bottom surface of the recess with a pressure required to secure the sealing property. That is, the amount of pressing deformation of the O-ring 17 is fixed by the abutment between the abutment surface 24a and the bottom surface of the recess.

As a result, like the first embodiment,
Outside air from the holes of the camera body 1 and the base member 2 is O
The ring 17 reliably seals and prevents outside air from entering the air gap of the color separation prism G.

In assembling and holding, the tightening amount of the nut 5 is determined by the abutting surface 24a of the nut 24 abutting against the bottom surface of the recess, and the O-ring 1 at this time.
Since the amount of pressing deformation of 7 is always the same, it is unlikely that the work will vary and an incomplete sealed state will not easily occur.

Moreover, since the O-ring 17 can obtain a sufficient sealing effect, it is possible to eliminate the conventional sealing of the blind lid itself or the adhesive of the blind lid, which seals the concave portion. Therefore, assembling workability can be improved as a whole.

In each of the above-described embodiments, an O-ring is arranged between the bolt or nut and the base member 2, and the abutting surface of the bolt or nut is abutted against the base member 2. An O-ring may be arranged between the nut and the camera body, and the abutting surface of the bolt or nut may abut the camera body 2.

Further, in each of the above embodiments, the video camera provided with the color separation prism has been described, but the present invention can be applied to various optical devices in which the optical element is fixed in the device main body by using the fastening member. it can. For example, it can be applied to a projection type image display device (projector) provided with a color separation prism or a color synthesis prism.

[0032]

As described above, according to the present invention,
By abutting the abutting portion of the fastening member with the base member or the main body of the device, the amount of pressing deformation of the elastic seal member can be made constant, and this elastic seal member ensures that the outside air enters the periphery of the optical element. Can be prevented.

As a result, it is possible to prevent the amount of pressing deformation of the elastic seal member from changing due to variations in work, and to seal the space between the blind cover and the base member with an adhesive as in the conventional case. It is possible to eliminate the need and eliminate the blind lid itself, and it is also possible to improve the assembly workability.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a seal unit in a video camera that is a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a seal unit in a video camera that is a second embodiment of the present invention.

FIG. 3 is a diagram showing a color separation optical system of a conventional video camera.

FIG. 4 is an enlarged view of a seal portion in the color separation optical system.

FIG. 5 is a diagram showing an invasion path of outside air in the seal portion.

[Explanation of symbols]

1 camera body 2 Base member 3 sub-base 4,14,25 Volts 14a, 24a abutting surface 5,25 nuts 17 O-ring G color separation prism

Claims (3)

[Claims] 1. An optical device in which a base member to which an optical element is attached is fixed to a device body using a fastening member, and an elastic seal member is pressed between the fastening member and the base member or the device body. An optical device, which is deformed and arranged, and wherein the fastening member is provided with an abutting portion which is abutted against the base member or the device body to determine a pressing deformation amount of the elastic seal member. 2. The optical device according to claim 1, wherein the fastening member includes a bolt and a nut, and the abutting portion is provided on one of the bolt and the nut. 3. The optical device according to claim 1, wherein the optical element is a prism-shaped optical element.