JPH0618349Y2 - Holding sheet for transparent subjects - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION This invention relates to a holding sheet for a transparent subject, particularly a slide film held there.
The present invention relates to a holding sheet suitable for use in projecting an image of a transparent subject such as a slide with a projector having an autofocus device while maintaining the holding state.

[0002]

2. Description of the Related Art A holding sheet widely used in the past for organizing, storing and projecting a transparent object such as a slide film is shown in FIG.

The holding sheet 1 here is provided by aligning a plurality of rectangular recesses 2 on one transparent or translucent plastic sheet, and on the two side walls of each of these recesses 2 facing each other, the recesses are formed therein. 2 form the ear pieces 3 and 3 that project laterally inward, and their bottom walls 4
At the edge of the object, a subject supporting portion 5 is provided which protrudes upward from the edge toward the inside of the recess 2.

Here, the slide film is inserted into the recess from the tip side of the ear pieces 3 and 3, and the film mount is positioned on the subject support portion 5, so that the slide film is inserted into the recess. Hold horizontally.

For this reason, when a plurality of sheets are bound by the binder 6 as shown in the drawing using the binding holes provided on one side of the holding sheet 1, a large amount of slide films can be easily and surely arranged. , Can be saved.

When the slide film is arranged and stored, the bottom wall 4 of the depression is located sufficiently apart from the emulsion fixing surface of the slide film except the subject supporting portion 5, so that the emulsion fixing surface is , It is possible to effectively protect the outer surface of the bottom wall from contact with other objects. Moreover, when the holding sheet 1 is formed of a semitransparent plastic sheet, the bottom wall 4 diffuses the light rays from the back surface side of the holding sheet 1 and transmits them to the front surface side thereof, so that the holding sheet 1 is transparently seen. As a result, all the slide films held on the holding sheet 1 can be seen and inspected extremely clearly, and a specific slide film can be easily searched.

However, such a conventional holding sheet interferes with the accurate operation of the automatic focusing device when a film image is projected by an overhead type projector as shown in FIG. 2 while holding the slide film thereon. was there.

That is, in the projector here, the upper surface of the projector main body 7 housing the light source system is closed by the transparent diffusion plate 8, and the position directly above the condenser lens 9 protruding from the transparent diffusion plate 8 While the projection lens 11 and the reflecting mirror 12 are attached to the arm member 10 whose one end is fixed to the projector body 7, the stage 13 located above the condenser lens 9 and movable in the two-dimensional direction in the horizontal plane,
The holding sheet 1 is detachably attached, and further, the arm member 10
And an automatic focusing device 15 for detecting the vertical position of the slide film 14 aligned with the holding sheet 1 and moving the projection lens 11 in the axial direction thereof.

The projection by the projector is
The light flux passing through the condenser lens 9 from the light source system is passed through the slide film 14 held horizontally and the projection lens 11 whose focus is adjusted, and finally reflected by the reflecting mirror 12 onto the screen. But,

The optical system of the autofocus device 15 in this projector is as shown in FIG.
A light emitting tube 18 surrounding the light source 16 and the focusing lens 17 and a light receiving tube 21 surrounding the focusing lens 19 and the light receiving element 20 are tilted by approximately 45 ° in opposite directions with respect to the optical axis of the projection lens 11 in the same vertical plane. Since this optical system is used for projecting the slide film 14 horizontally held by the conventional holding sheet 1 shown in FIG. 1, for example, as shown in FIG. , Luminous tube 18
The thin light flux A emitted from the light is reflected at almost the center of the slide film 14, and the reflected light B is reflected by the light receiving element 20.
Since it is not necessary to move the projection lens 11 at all in the center portion of the light flux A, a part of the light flux A passing through the slide film 14 is
The reflected light C is reflected by the flat hollow bottom wall 4 provided in the holding sheet 1, and affects the light receiving element 20 in the light receiving tube 21 to operate the projection lens 11, and as a result,
The clarity of the projected image on the screen was often compromised.

The parts other than the optical system of the autofocus device 15 are not shown here because they are known in the prior art and are not directly related to the gist of the present invention.

On the other hand, in addition to the above-mentioned prior art, as disclosed in Japanese Utility Model Publication No. 45-18339, an insert portion for holding a slide plate is formed on a synthetic resin thin plate, and the bottom surface of the insert portion is molded. The lower half of the upper half is inclined toward the rear to form an inclined recess, and a pillow is projected on the front of the upper half, and recesses are formed on both left and right side walls to attach a transparent thin film. A slide photo holding case has also been conventionally proposed. According to this photo holding case, the slide plate is easily inserted by inserting the slide plate along the pillow portion into the insertion portion from an oblique direction. It is possible to insert it without damaging the film surface, the slide plate after insertion is protected by a transparent thin film, and there is no fear of falling off from the insertion part,

Further, when the slide plate is taken out, if a finger is inserted into the pointing portion and the lower end edge of the slide plate is pushed out from the push-out portion, the slide plate is pushed obliquely upward in the inclined state. However, it does not directly contact the synthetic resin thin plate and the transparent thin film, and the film surface is not damaged.

However, in this photographic holding case, the pillow portion functioning as the support portion of the film mount is provided in front of the upper half portion of the insertion portion, but any other portion, in other words, There is no mount support part corresponding to the pillow part on the rear half or the left and right sides of the insertion part, and moreover, the lower half part of the insertion part is formed to be inclined toward the rear. Since the inclined concave portion is provided, it is substantially impossible to hold the slide plate inserted into the insertion portion in a horizontal posture,

Further, in the holding case, although the slide plate inserted into the insertion portion can be prevented from falling off, it is impossible to position and hold the slide plate at a predetermined position in the insertion portion.

Even if the holding case is applied to the above-mentioned overhead type projector for the purpose of projecting the film image of the slide plate housed in the photographic holding case, a clear projection is made at a predetermined position on the screen as a whole. There is a problem that cannot bring an image.

That is, in this conventional case, the slide plate inserted into the insertion portion is always positioned in a tilted state within the insertion portion, so that any one of the slide plates can be placed on the slide plate by the autofocus device of the projector. Even if it is possible to focus, many other parts will be out of focus, and as a result, the projected image on the screen will be out of focus for viewing and other reasons. In addition, since the slide plate cannot be positioned and held in the insertion portion, the projection image often deviates largely from the screen.

In addition, in this conventional case, when it is applied to an overhead type projector, the transparent thin film functioning as a fall-off preventing means and a protecting means for the slide plate ensures accurate operation of the automatic focusing device. 1
Similar to the recessed bottom wall 4 of the holding sheet 1 shown in the figure, there is an extremely high risk of obstruction, and similarly, an inclined recessed portion located very close to the slide plate inserted in the insertion portion also has the same effect.
It is likely to interfere with the correct operation of the autofocus device.

[0019]

[Means and Actions for Solving the Problems]
The present invention advantageously solves the problems of the prior art without impairing the inherent advantages of the conventional holding sheet shown in FIG. 1, and particularly, the center of the image area of a transparent subject on the bottom wall of each rectangular depression. Only the portion corresponding to the portion is provided with at least one of the upper side and the lower side of the bottom wall, a flat surface-shaped or curved surface-shaped inclined surface, and the inclined surface is projected to the upper side of the bottom wall. By making the height lower than that of the subject support section, the luminous flux emitted from the light emitting tube of the automatic focusing device and passing through the slide film is reflected by the inclined surface in a direction different from that of the light receiving tube. The present invention provides a holding sheet for preventing malfunction of the automatic focusing device.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

4 and 5 are a partially enlarged perspective view and a sectional view, respectively, showing an embodiment of the present invention.

Reference numeral 31 in the figure denotes a holding sheet, and this holding sheet 31 is also made of one transparent or semitransparent plastic sheet.

Here, in this kind of plastic sheet,
A plurality of rectangular recesses 32 are provided in an aligned manner, and an ear piece 34 protruding substantially horizontally from the two side walls 33 facing each other of the rectangular recesses 32 to the inside of the recess 32 is provided. The ear piece 34 in the illustrated example is formed by cutting and raising from the bottom wall 35 of the recess 32, the side wall 33, and one of the other two side walls 36 orthogonal to the side wall 33.
It can also be formed by cutting and raising it from the bottom wall 35 and an intermediate portion in the longitudinal direction of the.

Further, at the edge of the recess bottom wall 35, at a position close to each side wall 36, the subject support portion 37 protruding upward from the bottom wall 35 to the inside of the recess 32.
To provide. The shape and dimensions of the subject support portion 37 are
Various choices can be made as long as it can be supported above the bottom wall 35 at a position outside the image area of the slide film, but the one on the tip side of the ear piece of the support portion 37 here is the side walls 33 and 36. Has a U-shaped planar shape in contact with, and the ear piece base side thereof has a linear planar shape in contact with the side wall 36.

Further, here, in a substantially central portion of the bottom wall 35, in other words, in a region corresponding to the central portion of the image area of the transparent subject of the bottom wall 35, a flat surface shape protruding above the bottom wall 35 is formed. The inclined surface 38 of the
Is tilted so that its lower side faces the tip side of the ear piece 34. Here, the height of protrusion of the inclined surface 38 toward the upper side of the bottom wall is set lower than that of the subject support portion 37, so that the emulsion fixing surface of the slide film is sufficiently protected.

In order to hold the slide film 39 with a mount on such a holding sheet 31, first, it is pinched in the width or thickness direction and one end thereof is positioned below the ear piece 34 ( (See FIG. 5),
Then, by pressing the other edge with a finger, the ear piece 3
Under the elastic deformation of No. 4, one end thereof is allowed to ride on the subject support portion 37 on the ear piece base side through the inclined surface 38. As a result, the other end of the slide film 39 is positioned on the subject support portion 37 on the tip side of the ear piece, and the slide film 39 is based on the elastic force of the ear piece 34, and within the depression, It is firmly clamped in a horizontal position between the support portion 37 and the support portion 37.

In such a holding state of the slide film 39, the bottom wall 35 having the inclined surface 38 effectively protects the emulsion fixing surface of the slide film 39 and the see-through of the slide film 39 as described in the prior art. ,
Functions such as facilitating inspection can be exhibited.

The slide film 39 can be removed from the holding sheet 31 by inserting a finger into the recess 40 provided in the side wall 36 on the ear piece base side, and then using the slide film 3
By pressing one end edge of the insertion tip side of 9,
Easily done.

FIG. 6 shows a holding sheet 31 according to the present invention.
FIG. 9 is a schematic cross-sectional view of a case where the image is projected while holding the slide film 39 on the substrate. According to the holding sheet 31 of the present invention, a part of the thin light flux A emitted from the light emitting tube 18, which is represented by the same number as the optical system of the automatic focusing device shown in FIG. 3, passes through the slide film 39. However, due to the existence of the inclined surface 38, the light receiving element 20 is not affected by the reflected light C from the inclined surface 38. In other words, it is provided at a preselected central position on the bottom wall 14,
For example, the inclined surface 38 that is inclined by α ° with respect to the horizontal plane has a part of the light flux A that has passed through the film at the position where the slide film 39 and the optical axis of the projection lens 11 intersect with respect to the reflected light B that is reflected by the film surface. Reflected light C tilted outward by 2α °
Therefore, there is no possibility that the reflected light C will enter the light-receiving cylinder and affect the light-receiving element 20.

Therefore, the light receiving element 20 receives only the reflected light B from the film surface, and extremely accurate focus adjustment becomes possible.

FIG. 7 is an explanatory view showing another embodiment of the present invention, in which the inclined surface 38a is formed by the light emitting cylinder 18 and the light receiving cylinder 2.
It is tilted in a direction orthogonal to a plane including 1.

According to this example, the reflected light C is diverted in the direction orthogonal to the reflected light B, so that it is possible to more sufficiently eliminate the possibility that it will enter the light-receiving cylinder 21.

Incidentally, when the inclined surface 38 shown in FIG. 6 and the inclined surface 38a of this example are combined, the influence of the reflected light C on the light receiving element 20 can be removed more advantageously. Further, in the illustrated example, when a curved surface is interposed in the inflection portion of the inclined surfaces 38 and 38a shown in an exaggerated manner, the bent portion for forming the inclined surface is projected on the screen when projecting a film image. It is possible to reliably remove the influence on the.

FIG. 8 is a partial sectional view showing still another example of the inclined surface. The inclined surfaces 38b and 3 shown in FIGS. 8 (a) and 8 (b).
All of 8c are slopes that project and incline below the recess 32, that is, below the bottom wall 35. These slopes 3
8b and 38c, they are further separated from the emulsion fixing surface of the slide film 39 held in the recess 32 than in the above-mentioned example, so that the emulsion fixing surface is more effectively protected against the action of external force. You can Further, the inclined surface 38d shown in FIG. 8 (c) is an inclined surface protruding and inclining in the respective directions of the upper side and the lower side of the bottom wall 35.
According to 8d, when the holding sheet 31 is manufactured, the draw forming depth can be made relatively shallow to obtain a slope having a sufficient length. Furthermore, the inclined surfaces 38e, 3 shown in FIGS. 8 (d), (e)
Each of 8f is an inclined surface having a curved shape, and the inclined surfaces 38e and 38f can sufficiently remove the influence of the inclined surfaces 38e and 38f on the projected image on the screen.

The present invention has been described above based on the illustrated example, but the present invention can be applied not only to the holding sheet for the slide film but also to the same holding sheet for the slide.

[0036]

Therefore, according to the present invention, by holding the transparent object in a predetermined position in the depression in a horizontal position as expected, a clear projection image can be entirely displayed at a predetermined position on the screen. Of course, it can be brought about by the inclined surface provided in the approximately central portion of the bottom wall of the recess,
By reflecting the light flux reaching it in a direction other than the direction of the light receiving tube of the automatic focusing device, the light receiving element is not adversely affected by the reflected light, and proper focusing is always performed.

[Brief description of drawings]

FIG. 1 is a perspective view illustrating a conventional holding sheet.

FIG. 2 is a perspective view showing an overhead type projector.

FIG. 3 is a cross-sectional view showing a relationship between an optical system of an automatic focusing device and a conventional holding sheet.

FIG. 4 is an enlarged partial perspective view showing an embodiment of the present invention.

5 is a cross-sectional view taken along the line VV of FIG.

FIG. 6 is a sectional view showing a relationship between a holding sheet and an optical system according to the present invention.

FIG. 7 is a sectional view showing a relationship between a modified example of the present invention and an optical system.

FIG. 8 is a partial cross-sectional view showing another embodiment of the inclined surface.

[Explanation of symbols]

 31 Holding sheet 32 Rectangular recess 33, 36 Side wall 34 Ear piece 35 Bottom wall 37 Subject support 38, 38a, 38b, 38c, 38d, 38e, 38f Inclined surface 39 Slide film

Claims (1)

[Scope of utility model registration request] 1. A plurality of rectangular recesses aligned with each other, ear pieces projecting inwardly from two mutually facing two side walls of each of these rectangular recesses, and a pair of respective rectangular pieces orthogonal to the two side walls. In a holding sheet for a transparent subject, which comprises a subject supporting portion projecting upward from the bottom wall of the rectangular depression in the vicinity of the side wall, the bottom wall of each rectangular depression corresponds to the central portion of the image area of the transparent subject. The flat surface-shaped or curved-surface-shaped inclined surface that protrudes to either the upper side or the lower side of the bottom wall is provided only in the portion to be covered, and the protruding height of the inclined surface to the upper side of the bottom wall is provided. A holding sheet for a transparent subject, which is lower than that of the subject supporting portion.