JPH08297328A - Portable overhead projector - Google Patents

Abstract

PURPOSE: To obtain a portable overhead projector largely reduced in size and weight as a whole and excellent in portability by reducing the size of a projection sheet. CONSTITUTION: The overhead projector is constituted of a projection unit 1 provided with a light source 11 and a projection lens 15, a stage 2 provided with a Fresnel lens 8 having a reflection surface facing the projecting unit 1 and an arm part 3 for housing the projecting unit 1 and the stage 2 in a state where they are folded. The arm part 3 is formed in the size of a bible of about B6-size and a picture is formed on a picture forming sheet in about a diary size which is releasably stuck to a mount printable by a printer, etc., to prepare a picture projection sheet 9. Therefore, the picture projection sheet 9 in about a diary size can be easily and simply prepared without requiring a special device adopting a photographic system, etc. Thus, the stage 2 can be formed in about a diary size, the whole of the device can be reduced in size and weight and the size of the folded overhead projector becomes the size of a bible of about B6-size.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable overhead projector.

[0002]

2. Description of the Related Art In an overhead projector, an image projection sheet on which a projected image is formed is placed on a stage table, and the image projection sheet is irradiated with light from a light source.
The image of the image projecting sheet is enlarged and projected on the screen by a projection lens. The image projection sheet used in this overhead projector is a transparent sheet on which a projected image is formed. In order to easily print information such as documents and images created by a popular personal computer or word processor with a printer. In addition, A4 size paper is widely used.

[0003]

By the way, such an overhead projector is required to be excellent in carrying in order to strongly support sales activities of a salesperson, and various types have been developed in response to this. Although it has been commercialized, since the image projection sheet can be used up to A4 size, the stage table cannot be made smaller than the A4 size image projection sheet,
It is difficult to further reduce the size, and for this reason, it is the current situation that a salesperson cannot put it in a bag or a bag and carry it easily.

In order to meet such a situation, the inventor of the present application pays attention to the size of the image projecting sheet and reduces the size of the image projecting sheet, thereby reducing the size, weight and carrying of the entire apparatus. I examined the sex. As a result, it has been found that there are various problems as follows. For example, if the image projection sheet is simply reduced to the size of a notebook, it cannot be conveyed by the feed rollers of a printer or a copying machine, so that the information created by an existing personal computer or word processor can be easily printed by the printer, or I cannot make a copy of what I printed. Therefore, a special device such as a photographic system is required. Also, if a small-sized image projection sheet can be used, the stage base can be made smaller to downsize the entire apparatus, but simply downsizing does not necessarily mean that a sales person is in a bag or bag. It is not always possible to obtain a product with excellent portability that can be put in a portable device. Moreover, even if it is excellent in portability, a clear and good projected image cannot be obtained unless the optical path length from the light source to the projection lens can be secured.

The present invention has been made in consideration of the above problems, and a first object thereof is to provide a portable overhead projector in which a projection sheet is downsized, and a second object. It is an object of the present invention to provide a portable overhead projector which is excellent in portability while achieving a large reduction in size and weight of the entire device.

[0006]

In order to achieve the first object, the invention according to claim 9 is for producing an image of a notebook size or less which is releasably attached to a mount for printer printing or copying machine. A sheet is provided, and an image is formed on the image forming sheet to be used as an image projecting sheet. In order to achieve the second object, the invention according to claim 1 comprises a projection unit, a stage base, and an arm portion, each portion has substantially the same planar size, and these portions are foldably attached, and The feature is that the folded size of these is less than the size of the Bible of B6 size. In this case, as described in claim 2, the projection unit includes at least a light source and a projection lens, and the stage base has a reflection surface for reflecting light from the light source toward the projection lens and a reflection light by the reflection surface. A Fresnel lens for condensing light is preferably installed on the projection lens, and particularly, as described in claim 3, the Fresnel lens preferably has a thickness of 1 mm or less. In order to achieve the second object, the invention according to claim 5 comprises a projection unit, a stage base, and an arm portion.
The projection unit and the stage base are folded and housed in the arm portion. The invention according to claim 6 comprises the projection unit, the stage base, and the arm portion, and the projection unit and the arm are provided in the stage base. It is characterized by accommodating parts.

[0007]

According to the ninth aspect of the present invention, since the image forming sheet having a size smaller than the notebook size is detachably attached to the mount for printer printing or copying machine, the image forming sheet can be made as small as the notebook size. However, you do not need a special device such as a photographic system, you can print information such as documents and images created by existing personal computers or word processors on the image creation sheet with a printer, or copy the printed one. It is possible to easily and easily create an image projection sheet of a size equal to or smaller than the size of a notebook by making a reduced copy with a machine.

Thus, according to the first aspect of the present invention, it is possible to form the stage base in a size of a notebook size, and accordingly, the projection unit and the arm portion are substantially the same size as the stage base. Since it can be formed into a large size, the size and weight of the entire device can be greatly reduced, and since each part can be folded, it can be made compact by folding each part, and the folded size is about B6 size. Is less than or equal to the size of the Bible,
A salesperson can carry it in a bag or a bag, and can obtain something with excellent portability. In this case, the light source and the projection lens are provided in the projection unit, and the reflecting surface and the Fresnel lens are installed in the stage base as described in claim 2, so that even if the size of the entire apparatus is reduced, the light source and the projection lens are provided. The optical path length can be sufficiently secured, and if the Fresnel lens has a thickness of 1 mm or less as described in claim 3, even if the optical path length becomes short, the deviation of the projected image by the Fresnel lens is small, A clear and good projection image can be obtained.

According to the fifth aspect of the invention, since the projection unit and the stage base are folded and housed in the arm portion which can be formed to a size of a notebook, the arm portion is compact. Since the projection unit and the stage base can be protected by, it is extremely portable. Further, according to the invention of claim 6, since the projection unit and the arm portion are folded and housed in the stage base that can be formed to a size of a notebook size, the stage base can be left on the table. The projection unit and arm can be folded and stored and set up, and they have good workability, are easy to handle, and are compact when folded, which makes them extremely portable.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a portable overhead projector according to the present invention will be described below with reference to FIGS. FIG. 1 is a perspective view of a portable overhead projector in use, and FIGS.
FIG. 4 is a perspective view showing a folding process of the portable overhead projector. This portable overhead projector is composed of a projection unit 1, a stage base 2, and an arm section 3. The planar size of each of these sections is approximately the same size, and each section is foldably attached, and as shown in FIG. As shown in the figure, the folded size is almost the same as the size of a B6 size Bible.

That is, the arm portion 3 is made of synthetic resin or metal, and as shown in FIG. 1, is formed in a substantially box shape with the upper surface and the right side surface opened, and the size thereof is a B6 size of B6 size. For example, the width is about 130 mm, the height is about 180 mm, and the thickness is about 50 mm. Opposing surface 3 at the lower inside of this arm portion 3
A support shaft 4 is bridged on the inner side between a and the one end portion (the left end portion in FIG. 1) of the stage base 2 is rotatably attached to the support shaft 4. Further, a support shaft 5 is bridged on the inner side of the upper part of the arm portion 3 between the facing surfaces 3a, and one end portion (the left end portion in FIG. 1) of the unit case 6 of the projection unit 1 is bridged over the support shaft 5. ) Is rotatably attached.

The stage base 2 is made of synthetic resin and is shown in FIG.
As shown in FIG. 2, it is formed in a flat plate shape having substantially the same size as the inner surface 3b on the inner side of the arm portion 3 and rotates about the support shaft 4, and as shown in FIG. 1 and the other end side (the right end side in the figure) horizontally projects from the arm portion 3 as shown in FIG. A Fresnel lens 8 having a reflecting surface 7 is provided on the upper surface 2a of the stage base 2, that is, one surface corresponding to the inner surface 3b on the inner side of the arm portion 3. On the Fresnel lens 8, an image projection sheet 9 of a notebook size, which will be described later, is placed. The lower surface 2b of the other end of the stage base 2 protruding from the arm portion 3 has an upper surface 2a of the stage base 2 when the stage base 2 horizontally protrudes from the arm portion 3.
Is provided with a leg portion 2c for holding it horizontally.

The unit case 6 of the projection unit 1 is made of synthetic resin, and as shown in FIGS. 1 and 2 (c),
It is formed to be a little smaller than the internal shape of the arm portion 3, so that it is housed in the arm portion 3 together with the stage base 2. A distribution duct 10 is provided on the support shaft 5 side (the left end in FIG. 1) in the unit case 6,
A light source 11 is arranged in the circulation duct 10, and slit-shaped air circulation holes 13 (one of which is not shown) are provided on both side surfaces of the unit case 6 corresponding to both ends of the circulation duct 10. There is. The distribution duct 10 is a metal rectangular tube, is arranged along the support shaft 5, and has a light source 11
Is provided with an opening (not shown) through which light passes, and a cooling fan 12 is provided at one end. The cooling fan 12 is a unit case 6
External cold air is introduced from the air circulation hole 13 on one side, and warm air inside is introduced into the air circulation hole 1 on the other side.
The light source 11 is cooled by discharging the light source 11.

A recess 14 is formed on the upper surface of the unit case 6 on the other end side (the right end side in FIG. 1) so as to extend over the front end surface. In the unit case 6 corresponding to the recess 14, the projection lens 15 is movably arranged along the optical axis of the projection lens 15 while being exposed from the bottom surface of the recess 14. Further, in the unit case 6 at a position corresponding to the recess 14, a focus adjusting knob 16 for adjusting the focal position of the projection lens 15 by moving the projection lens 15 along the optical axis thereof has a part thereof recessed. Is provided so as to project from the front end surface to the front end surface.

Further, in the concave portion 14 of the unit case 6, a total reflection mirror 17 is provided on the lower surface facing the projection lens 15.
A flat plate-shaped lid 18 provided with is attached so that it can be erected sideways. That is, the lid 18 has one end (see FIG.
A pin (not shown) is provided on both sides of the left lower end) so as to project laterally, and the pin is movably inserted in a guide groove 19 provided on the back side of the facing surface in the recess 14, and One end (upper end in the figure) of the support lever 20 is rotatably attached in the middle, and the other end (lower end in the same figure) 20a of this support lever 20 is on the front side (right side in the same figure) of the guide groove 19. The support lever 20 is rotatably attached to the inner surface of the recess 14, and the support lever 20 rotates about the other end 20a of the support lever 20 so that the pin moves up and down in the recess 14 while moving in the guide groove 19. ing. Therefore, this lid 1
The reference numeral 8 covers and protects the projection lens 15 in a state where the projection lens 15 is accommodated in the concave portion 14 in a laid-down state, and in the upright state, the pin is locked to a locking portion (not shown) of the guide groove 19 and the support lever 20 is provided. Is supported by being inclined at a predetermined angle.

By the way, the stage base 2 and the unit case 1 are each provided with a lock mechanism 21 for locking them to the arm portion 3 when the stage base 2 and the unit case 1 are arranged so as to project horizontally from the arm portion 3. There is. The lock mechanism 21 is provided with a stage base 2 and a unit case 1.
Both have the same structure. Here, the lock mechanism 21 on the stage base 2 side will be described. The lock mechanism 21 is provided on both sides of the stage base 2 on the support shaft 4 side, and includes a U-shaped lock pin 22 and a coil spring 23 as shown in FIGS. 3 (a) and 3 (b). There is.
The lock pin 22 is slidably disposed in the hollow portion 24 of the stage base 2 in the protruding and retracting directions of the both ends 22a and 22b with both ends 22a and 22b exposed from the side surface of the stage base 2. The coil spring 23 is arranged on the outer periphery of the lock pin 22 on the one end 22a side in the hollow portion 24 and urges both ends 22a and 22b of the lock pin 22 in a direction to push it out. In this lock mechanism 21, when the stage base 2 horizontally projects from the arm portion 3, one end 22a of the lock pin 22 pushed out by the spring force of the coil spring 23 causes the arm portion 3 to move as shown in FIG. By inserting into the locking hole 25 provided on the inner surface to lock the stage base 2 and pressing the other end 22b of the lock pin 22 protruding to the outside of the arm portion 3 against the spring force of the coil spring 23. As shown in FIG. 3B, the one end 22a is disengaged from the locking hole 25 of the arm portion 3 to unlock the stage base 2. As shown in FIG. 2A, the support shaft 5 to which the unit case 6 is attached is attached with a torsion spring 26 that urges the unit case 6 in the direction of pushing it out of the arm portion 3.

Next, the optical path of this portable overhead projector and each optical element on the optical path will be described with reference to FIG. The light source 11 arranged in the projection unit 1 includes a halogen lamp 30 and a reflector 31,
The halogen lamp 30 is arranged at or near the focal point of the reflector 31, and the light of the halogen lamp 30 is condensed by the reflector 31 toward the front total reflection mirror 32 side. In this case, the halogen lamp 30 is 1
It is 130 W at 00V. The reflecting surface of the reflector 31 is
The dichroic mirror is formed to have a focal length fR of about 43 mm and transmits infrared rays and reflects other light in order to reduce heating due to heat generation of the halogen lamp 30. Total reflection mirror 32
Are arranged at a predetermined angle with respect to the optical axis 33 of the light source 11 in order to reflect the light condensed by the reflector 31 toward the Fresnel lens 8 of the stage base 2. In this case, the distance L1 from the optical axis 33 of the light source 11 to the upper surface of the Fresnel lens 8 is set to about 183 mm.

The Fresnel lens 8 is for focusing incident light on the projection lens 15 of the projection unit 1.
As shown in FIG. 5, the upper surface is formed into a flat surface, the lower surface is formed into a Fresnel surface, and the reflecting surface 7 is integrally formed on the Fresnel surface of this lower surface by aluminum sputtering. The Fresnel lens 8 is made of an acrylic sheet and has a thickness of 1 mm or less, preferably a total thickness t1 of about 0.4 mm, a lens cut thickness t1 of about 0.2 mm, and a Fresnel ring pitch. p is 0.3
It is formed to about 5 mm. The Fresnel lens 8 has a size of about 100 × 100 mm, and its focal length f1 is set to about −100 mm.
Further, the angle θ1 formed by the incident light and the outgoing light on the upper surface of the Fresnel lens 8 is the total reflection mirror 32 and the projection lens 15.
Since the distance L1 from the optical axis 33 of the light source 11 to the upper surface of the Fresnel lens 8 is as short as about 183 mm even when is closest to, the angle is set to about 14 °.

The projection lens 15 enlarges and projects an image of the image projection sheet 9 placed on the Fresnel lens 8 onto a screen (not shown) via the total reflection mirror 17 of the lid 18. When the focal length f2 is about 165 mm,
F-number is about 3.5 and projection distance is 1.5-3.0
In m, the magnification is set to 7 to 15.0 times. In addition,
The total reflection mirror 17 of the lid 18 is supported in the concave portion 14 of the unit case 6 at a predetermined angle so that the optical axis 35 of the reflected light is slightly higher than horizontal.

By the way, as shown in FIGS. 6A and 6B, the image projection sheet 9 placed on the Fresnel lens 8 of the stage base 2 has a size of a notebook (for example, 130 × 8 cm). A transparent image forming sheet having a size of (about) is releasably attached to a postcard size mount 36 that can be printed by a printer or copied by a copying machine, and an image is formed on the image forming sheet. . In this case, the image projecting sheet 9 has an image forming area 37 formed in the central portion thereof in a size of about 9 × 6 cm. Further, a plurality of binder holes 38 are formed at substantially equal intervals on one side in the longitudinal direction of the image projection sheet 9, and cut portions 39 are formed from the binder holes 38 to the end sides. Are formed. The cut portion 39 is for attaching and detaching the image projection sheet 9 as it is without opening the binder.

In such a portable overhead projector, an image forming sheet of about a notebook size is removably attached to a mount 36 of about a postcard size, so that the image forming sheet can be reduced to about the notebook size. Without using a special device such as a photographic method, you can print information such as documents and images created by existing personal computers or word processors on a sheet for image creation with a printer, or reduce it with a copier. By doing so, it is possible to easily and easily create the image projection sheet 9 having a size of a notebook size or smaller. As described above, by using the image projection sheet 9 having a size of a notebook, it becomes possible to form the stage base 2 to a size of a notebook, for example, a Bible size of B6 size. The unit 1 and the arm portion 3 can also be formed to have substantially the same size as the stage base 2, so that the size and weight of the entire apparatus can be greatly reduced.

Further, in this portable overhead projector, since the projection unit 1 and the stage base 2 are rotatably attached to the arm portion 3 by the support shafts 4 and 5, respectively, the projection unit 1 and the stage base 2 are armed. It can be folded and stored in the part 3. In this case, first, the lock of the stage base 2 by the lock mechanism 21 is released, and the stage base 2 is rotated around the support shaft 4 as shown in FIG. Then, the lock by the lock mechanism 21 of the projection unit 1 is released, and the projection unit 1 is rotated about the support shaft 5 as shown in FIG.
As shown in (c), it is folded and stored in the arm portion 3 while being superposed on the stage base 2. This makes the entire device compact. At this time, since the arm portion 3 has a B6 size of B6 size, the entire folded size becomes a B6 size of B6 size. For this reason, a salesperson can easily carry it in a bag or a bag and obtain a highly portable product.

When using such a portable overhead projector, contrary to the above operation, first, the projection unit 1 is rotated so that a part thereof is projected horizontally from the arm portion 3 and locked in this state. The projection unit 1 is locked to the arm section 3 by the mechanism 21, and then the stage base 2 is rotated to partially project the part horizontally from the arm section 3. In this state, the stage base 2 is armed by the lock mechanism 21. The stage base 2 and the arm part 3 are placed on a table while being locked by the part 3, and then the lid 18 of the projection unit 1 is raised and supported by the support lever 20 at a predetermined angle shown in FIG. And the Fresnel lens 8 of the stage base 2
The image projection sheet 9 is placed on the light source 11 in this state.
The halogen lamp 30 is turned on. Then, as shown in FIG. 4, the light from the halogen lamp 30 is reflected by the reflector 3
The light is condensed at 1 and totally reflected by the total reflection mirror 32 toward the image projection sheet 9. Of the light radiated on the image projection sheet 9, the light radiated on the image portion 9a is shown in FIG.
As shown in (a), the light that is blocked by the image portion 9a and is applied to the other portion passes through the image projection sheet 9 and enters the Fresnel lens 8. This incident light is reflected by the reflecting surface 7 of the Fresnel lens 8 as shown in FIG. 7A, and of the reflected light, the light that reaches the image portion 9a is the image portion 9a.
The reflected light that has been blocked by, and reaches the other portion is transmitted through the image projection sheet 9 and is condensed by the Fresnel lens 8 on the projection lens 15. As a result, the image of the image projection sheet 9 is enlarged and projected as a projection image on the screen by the projection lens 15 via the total reflection mirror 17 of the lid 18.

By the way, in this portable overhead projector, when the light applied to the image projection sheet 9 is focused on the projection lens 15 by the Fresnel lens 8, from the optical axis 33 of the light source 11 to the upper surface of the Fresnel lens 8. Since the distance L1 is as short as about 183 mm, even if the total reflection mirror 32 and the projection lens 15 are brought close to each other at a minimum, the angle θ1 formed by the incident light and the outgoing light on the optical axis 34 on the upper surface of the Fresnel lens 8 is about 14 °. However, since the Fresnel lens 8 is formed as thin as 1 mm or less,
A good projection image can be obtained for the following reasons.

In the conventional apparatus, since the outer shape of the entire apparatus is large, the distance L1 from the optical axis 33 of the light source 11 to the upper surface of the Fresnel lens 8 can be set long, so that the total reflection mirror 32 and the projection lens 15 are separated from each other. If the distance is constant,
The angle θ1 formed by the incident light and the emitted light on the upper surface of the Fresnel lens 8 becomes small at about 5 to 7 °. Therefore, even if the Fresnel lens 8 is thick, the deviation of the projected image in the vertical direction is hardly noticeable. However, when the entire apparatus becomes small as in this embodiment, the distance L1 from the optical axis 33 of the light source 11 to the upper surface of the Fresnel lens 8 becomes as short as about 183 mm, and therefore the incident light and the emitted light on the upper surface of the Fresnel lens 8 are reduced. The angle θ1 formed by and becomes large at about 14 °. For this reason, when the Fresnel lens 8 is thick, the deviation of the projected image in the vertical direction becomes noticeable as follows.

That is, when the Fresnel lens 8 is thick, the image portion 9a of the image projection sheet 9 and the reflecting surface 7 of the Fresnel lens 8 are separated from each other, as shown in FIG. A part of the light emitted from 32 to the image projection sheet 9 is an image portion 9 a of the image projection sheet 9.
The first projection image 9b is produced by the reflection surface 7 at the position shown by the solid line in the figure by the reflection surface 7, and part of the light reflected by the reflection light 7 reaching the reflection surface 7 without being blocked by the image portion 9a. The second projection image 9c is created at the position indicated by the dotted line in the figure by being blocked by the image portion 9a of the image projection sheet 9. This first, second
Since the projected images 9b and 9c are separated without overlapping, the projected image projected by the projection lens 15 becomes a double image in which the first and second projected images 9b and 9c are vertically displaced. However, when the thickness of the Fresnel lens 8 is reduced to about 1 mm or less as in this embodiment, the image portion 9a of the image projection sheet 9 and the Fresnel lens 8 are formed as shown in FIG. Since the reflecting surface 7 approaches, the first projection image 9 by the light emitted from the total reflection mirror 32 to the image projection sheet 9
b is created at the position shown by the solid line in FIG.
The second projection image 9c formed by the light that reaches the reflection surface 7 and is reflected without being blocked by a is created at the position shown by the dotted line in the figure, and these first and second projection images 9b and 9c are displaced from each other. Little overlap and almost overlap. Therefore, even when the image is enlarged and projected on the screen, the first and second projected images 9b and 9c can be visually recognized as a unit, and a clear projected image can be obtained.

Further, in this portable overhead projector, the light source 11 is arranged in the distribution duct 10 arranged in the unit case 6, and the distribution duct 10 is arranged.
Since the cooling fan 12 forcibly introduces the external cool air into the inside, the light source 11 can be reliably cooled, which prevents the unit case 6 from being thermally deformed by the heat generated by the halogen lamp 30. In addition, since the distribution duct 10 is made of metal, the light source 11 can be strongly protected and the unit case 6 can be reinforced.

The Fresnel lens 8 of the first embodiment described above is used.
Has a total thickness t1 of about 0.4 mm, a lens cut thickness t2 of about 0.2 mm, and a Fresnel ring pitch p of 0.35.
Although the thickness is about 10 mm, the total thickness t1 of the Fresnel lens can be reduced to 0.4 mm or less as the Fresnel ring pitch p is reduced to 0.35 mm or less. By doing so, even if the distance L1 from the optical axis 33 of the light source 11 to the Fresnel lens 8 is shorter than that in the first embodiment, the deviation of the projected image can be suppressed, and the overall size of the apparatus can be further reduced. Can be achieved. Further, in the Fresnel lens 8 of the first embodiment, the reflecting surface 7 is integrally formed on the lower surface of the Fresnel lens 8 by sputtering aluminum.
The reflecting surface 7 does not necessarily have to be integrally formed, and a structure in which a reflecting plate is arranged below the Fresnel lens 8 may be used. In the first embodiment, the light from the light source 11 is reflected by the total reflection mirror 32 toward the Fresnel lens 8. However, the light from the light source 11 is directly condensed on the Fresnel lens 8 for irradiation. May be. Furthermore, in the first embodiment, when the image of the image projection sheet 9 is enlarged and projected by the projection lens 15, the direction of projection by the total reflection mirror 17 of the lid 18 is changed, but the total reflection mirror 17 is not necessarily used. It is not necessary to change the projection direction, and for example, by placing the arm unit 3 on a table so that the projection unit 1 and the stage base 2 stand vertically, the projection lens 15 projects the image directly on the screen in an enlarged manner. You may do it.

Next, a second embodiment of the portable overhead projector of the present invention will be described with reference to FIGS. The same parts as those of the first embodiment shown in FIGS. 1 to 7 are designated by the same reference numerals, and the description thereof will be omitted.
As shown in FIG. 8, this portable overhead projector includes a projection unit 1, a stage base 40, and an arm unit 4.
1, each of these parts is attached so as to be sequentially foldable, and as shown in FIG. 11, the size folded and stored in the stage base 40 is substantially the same as the size of a B6 size Bible. Has been done.

That is, the stage base 40 is made of synthetic resin or metal, and is formed in a substantially box shape with its upper surface and right side surface open, as shown in FIG.
The size of the Bible, such as a width of about 130 mm,
The vertical width is about 180 mm and the thickness (height) is about 50 mm. The Fresnel lens 8 having a reflecting surface on the lower surface is arranged on the bottom surface of the stage base 40, as in the first embodiment. This Fresnel lens 8
Similar to the first embodiment, it is formed in a size that allows the image projection sheet 9 of a notebook size to be placed, for example, a size of about 100 × 100 mm.

The arm portion 41 is made of synthetic resin and is shown in FIG.
As shown in FIG. 4, the flat plate portion 43 has a size corresponding to the bottom surface of the stage base 40, and side portions 44 provided on both side edges of the flat plate portion 43. It is rotatably attached to each support pin 42 provided on the upper left side of the inner surface facing each other, and by pivoting about each support pin 42, as shown in FIG. The structure is such that it stands up and is housed in the upper part of the stage base 40 as shown in FIG.

Similar to the first embodiment, the projection unit 1 includes a light source, a distribution duct, and a projection lens 1 in the unit case 6.
5, a lid 18 having a total reflection mirror is openably and closably attached to the concave portion 14 of the unit case 6, and the unit case 6 is provided on the other end side (the upper end side in FIGS. 8 and 9) of the arm portion 41. It is rotatably attached to a support shaft 45 spanned between the both side portions 44, and is rotated around the support shaft 45 in a state where the arm portion 41 is vertically erected, and becomes a horizontal state shown in FIG. As shown in FIG. 10, it has a structure in which it is in a vertical state in which it is in close contact with the inside of the arm portion 41. In this case, the unit case 6 is formed such that the upper and lower surfaces thereof have substantially the same size as the inner surface of the flat plate portion 43 of the arm portion 41, and the thickness thereof is smaller than that of the stage base 40.

The arm portion 41 is provided with the same lock mechanism 21 as in the first embodiment for locking the arm portion 41 with respect to the stage base 40 when the arm portion 41 stands upright on the stage base 40. . Further, the unit case 6 is provided with a similar lock mechanism 21 that locks the unit case 6 with respect to the arm portion 41 when the unit case 6 is arranged horizontally with respect to the standing arm portion 41.

In such a portable overhead projector, as in the first embodiment, by using the image projecting sheet 9 about the size of the notebook, the stage base 2 is about the size of the notebook, for example, a B6 size Bible. The projection unit 1 and the arm portion 41 can be formed to have substantially the same size as that of the stage base 40, so that the size and weight of the entire apparatus can be reduced. it can. Particularly, in this portable overhead projector, the unit case 6 of the projection unit 1 is rotatably attached to the arm portion 41 by the support shaft 45, and the arm portion 41 is rotatably attached to the stage base 40 by the support pin 42. Since it has been
First, the lock of the unit case 6 by the lock mechanism 21 is released and the unit case 6 is rotated to bring the unit case 6 into close contact with the inner surface of the arm portion 41 as shown in FIG. The arm portion 41 in which the mechanism 21 is released and the unit case 6 is folded.
By rotating, the arm portion 41 can be folded and housed in the stage base 40 together with the unit case 6 as shown in FIG. At this time, since the stage table 40 is about the size of the B6 size of the B6 size, the entire folded size is about the size of the Bible size of the B6 size. Can be easily carried in a bag or bag, and can be easily carried. Further, in the state where the respective parts are folded in this manner, the projection unit 1 is mounted on the stage base 40.
Since it is covered with the arm portion 41, the stage base 40 and the arm portion 41 can protect the projection unit 1 from an external impact or the like.

In the case of using this portable overhead projector, contrary to the above operation, first, the stage base 40 is placed on the table, and in this state, the arm portion 41 is rotated as shown in FIG. Then, the arm portion 41 is vertically erected above the stage base 40, and in this state, the arm portion 41 is locked to the stage base 40 by the lock mechanism 21.
As shown in FIG. 3, the projection unit 1 is rotated horizontally with respect to the arm portion 41, and in this state, the projection unit 1 is locked to the arm portion 41 by the lock mechanism 21 and the lid 18 of the projection unit 1 is raised. It is supported at a predetermined angle shown in FIG. Then, when the image projection sheet 9 is placed on the Fresnel lens 8 of the stage table 2 and the halogen lamp 30 of the light source 11 is turned on in this state, the image of the image projection sheet 9 is displayed as in the first embodiment. It can be enlarged and projected on the screen. In this case, the stage unit 40 in which the projection unit 1 and the arm unit 41 are folded and stored is placed on the table in advance, and the arm unit 41 and the projection unit 1 are sequentially rotated to perform setting. Therefore, the workability of setting is better than that of the first embodiment.

Next, a third embodiment of the portable overhead projector of the present invention will be described with reference to FIGS. Also in this case, the same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. This portable overhead projector, as shown in FIG.
The projection unit 1, the stage base 50, and the arm portion 51 are provided. The projection unit 1 and the stage base 50 are attached to each other by the arm portion 51 so that they can extend and contract. The unit 1 is housed, and the entire size of the unit 1 is configured to be substantially the same as the size of a B6 size Bible. That is, the stage base 50 is made of synthetic resin or metal, and is formed in a U-shaped cross section with its upper surface and left and right side surfaces open, as shown in FIG. 12, and its size is B6.
The size of the Bible, such as a width of about 130 mm,
The vertical width is about 180 mm and the thickness (height) is about 50 mm. A Fresnel lens having a reflecting surface on the lower surface is arranged on the bottom surface of the stage table 50, as in the first embodiment. This Fresnel lens is the first
Similar to the embodiment, it is formed in a size in which an image projection sheet of about a notebook size can be placed, for example, a size of about 100 × 100 mm. Similar to the first embodiment, the projection unit 1 is provided with a light source, a distribution duct, a projection lens, etc. in the unit case 6, and a lid 18 having a total reflection mirror is openably and closably attached to the recess 14 of the unit case 6. ,
The unit case 6 has a structure so formed as to be housed in the stage base 50. The arm part 51 is
As shown in FIGS. 12 and 13, two sets of left and right link mechanisms 52 made of synthetic resin or metal are provided. The link mechanism 52 includes a first link member 53 attached to the right side of the stage base 50 shown in FIG.
The second ring member 54 is attached to the left side of 0.

As shown in FIG. 12, the first link member 53 is composed of a lower arm 55 whose lower end is slightly bent and an upper arm 56 whose upper end is slightly bent. The lower end of the lower arm 55 is the stage table 50. Pin 5 on the right inside
7 is rotatably attached to the lower arm 55, and the lower end of the upper arm 56 is rotatably attached to the upper end of the lower arm 55 by a pin 58. The upper end of the upper arm 56 is attached to the right outer surface of the unit case 6 by a pin 59. It has a structure that is rotatably attached to. This first ring member 5
In the state in which the unit case 6 is pushed up above the stage base 50, the whole 3 has a V shape as shown in FIG. 12, and the upper end of the upper arm 56 of the first ring member 53 is the unit case. In the state where the unit case 6 is held in contact with the positioning stopper portion 60 of 6 and the unit case 6 is housed in the stage base 50, as shown by the dotted line in FIG. The pin 59 at the upper end of the upper arm 56 corresponds to the lower arm 5
5 and the upper arm 56 overlap.

On the other hand, the second ring member 54 is constructed symmetrically with the first ring member 53. That is, the second
In the ring member 54, the lower end of the lower arm 61 is rotatably attached to the inner surface on the left side of the stage table 50 by a pin 63, and the lower end of the upper arm 62 is rotatably attached to the upper end of the lower arm 61 by a pin 64. The upper arm 62 is attached and the upper end of the upper arm 62 is attached to the unit case 6 by a pin 65
Is rotatably attached to the outer surface of the left side of the unit, and the unit case 6 is pushed up above the stage base 50.
As shown in FIG. 12, when the unit case 6 is housed in the stage base 50 as a whole in an inverted V shape, as shown by the dotted line in FIG. The pin 65 at the upper end of the upper arm 62 corresponds to the lower arm 61 and the upper arm 62 and the first ring member 53.

In such a portable overhead projector as well, similar to the first embodiment, by using the image projection sheet of the size of the notebook, the stage table 50 is made to be the size of the notebook, for example, the Bible size of B6 size. Accordingly, the projection unit 1 and the arm portion 51 can be formed to have substantially the same size as the stage base 50, whereby the overall size and weight of the apparatus can be reduced. . In particular, in this portable overhead projector, the unit case 6 of the projection unit 1 is provided with the expandable and contractible arm portion 51 so that the stage base 5 can be prevented.
Since the link unit 52 of the arm unit 51 is bent and contracted, the projection unit 1 can be housed in the stage table 50 together with the arm unit 51 as shown in FIG. At this time, since the stage table 50 is about the size of the B6 size of B6 size, the entire folded size is about the size of the B6 size of B6 size. It can be easily carried by putting it in a bag or a bag, and a product with excellent portability can be obtained.

When this portable overhead projector is used, contrary to the above operation, with the stage base 50 placed on a table, the projection unit 1 is moved from the stage base 50 as shown in FIG. When pulled up, the link mechanism 52 of the arm portion 51 is extended accordingly, and the projection unit 1 is moved by the arm portion 51.
As shown in FIG. In this state, the lid 18 of the projection unit 1 is raised and supported at a predetermined angle shown in FIG. 12, the image projection sheet 9 is placed on the Fresnel lens 8 of the stage table 2, and the light source is turned on. Similar to the embodiment, the image of the image projection sheet can be enlarged and projected on the screen. In this case, since the projection unit 1 can be held above the stage table 50 by pulling up the projection unit 1 and extending the arm portion 41, as in the second embodiment.
The setting work can be easily performed.

[0041]

As described above, according to the invention of claim 9, the image forming sheet having a size smaller than the notebook size is releasably attached to the mount for printer printing or copying machine. Even if you reduce the size of the data sheet to the size of a notebook, you do not need a special device such as a photographic method, and you can print information such as documents and images created by existing personal computers or word processors on the image creation sheet with a printer. Alternatively, or by making a reduced copy of the printed matter with a copying machine, it is possible to easily and easily create an image projection sheet of a notebook size or smaller.

Thus, according to the first aspect of the present invention, the stage base can be formed to have a size of a notebook size, and accordingly, the projection unit and the arm portion have substantially the same size as the stage base. Since it can be formed into a large size, the size and weight of the entire device can be greatly reduced, and since each part can be folded, it can be made compact by folding each part, and the folded size is about B6 size. Is less than or equal to the size of the Bible,
A salesperson can carry it in a bag or a bag, and can obtain something with excellent portability. In this case, the light source and the projection lens are provided in the projection unit, and the reflecting surface and the Fresnel lens are installed in the stage base as described in claim 2, so that even if the size of the entire apparatus is reduced, the light source and the projection lens are provided. The optical path length can be sufficiently secured, and if the Fresnel lens has a thickness of 1 mm or less as described in claim 3, even if the optical path length becomes short, the deviation of the projected image by the Fresnel lens is small, A clear and good projection image can be obtained.

According to the fifth aspect of the invention, since the projection unit and the stage base are folded and housed in the arm portion that can be formed to a size of a notebook, the arm portion is compact. Since the projection unit and the stage base can be protected by, it is extremely portable. Further, according to the invention of claim 6, since the projection unit and the arm portion are folded and housed in the stage base that can be formed to a size of a notebook size, the stage base can be left on the table. The projection unit and the arm can be folded and stored and set up, and the workability is good, the handling is easy, and the folded unit is compact and extremely portable.

[Brief description of drawings]

FIG. 1 is a perspective view of a portable overhead projector according to a first embodiment of the present invention in use.

2A and 2B show the folding process of FIG. 1, in which FIG. 2A is a perspective view of a state in which a stage base is folded in an arm portion, and FIG. 2B is a perspective view of a state in which a projection unit is folded in an arm portion housing a stage base; FIG. 6C is a perspective view showing a state where the arm unit and the projection unit are housed in the stage base.

FIG. 3 shows a cross section taken along the line AA of the lock function of FIG. 1, (a)
Is an enlarged cross-sectional view showing a locked state of the stage base by the locking mechanism, and FIG. 6B is an enlarged cross-sectional view showing a state in which the stage base is unlocked by the locking mechanism.

FIG. 4 is a diagram showing the optical path of FIG. 1 and an optical element on the optical path.

FIG. 5 is an enlarged cross-sectional view of the Fresnel lens shown in FIGS. 1 and 4.

6 is a plan view showing the image projection sheet of FIG. 4, in which (a) is a plan view of a state in which an image forming sheet to be an image projection sheet is attached to a mount, and (b) is a side view thereof.

7A and 7B show an optical path state in a Fresnel lens, FIG. 7A is an enlarged view showing an optical path state in the case of using a thin Fresnel lens in this embodiment, and FIG. 7B is a conventional thick Fresnel lens. The enlarged view which shows the optical path state at the time of using a lens.

FIG. 8 is a perspective view showing a usage state of a second embodiment of a portable overhead projector according to the present invention.

9 is a side view of FIG.

10 is a perspective view showing a state in which the projection unit shown in FIG. 9 is bent into an arm portion.

FIG. 11 is a side view showing a state in which the folded arm portion of the projection unit of FIG. 10 is folded and stored in the stage base.

FIG. 12 is a side view of a portable overhead projector according to a third embodiment of the present invention in use.

13 is a front view of FIG.

FIG. 14 is a side view showing a state where the arm unit of FIG. 12 is expanded and contracted and the projection unit is pushed down toward the stage base.

FIG. 15 is a side view showing a state where the projection unit of FIG. 14 is further pushed down and stored in the stage base.

[Explanation of symbols]

 1 Projection unit 2, 40, 50 Stage base 3, 41, 51 Arm part 4, 5, 45 Support shaft 6 Unit case 7 Reflective surface 8 Fresnel lens 9 Image projection sheet 10 Distribution duct 11 Light source 15 Projection lens 36 Mount

Claims (9)

[Claims] 1. A Bible having a projection unit, a stage base, and an arm portion, each portion having substantially the same planar size, being foldably attached to each portion, and having a folded size of about B6 size. The size of the portable overhead projector is less than or equal to the size. 2. The projection unit includes at least a light source and a projection lens, the stage base reflects a light from the light source toward the projection lens, and the light reflected by the reflection surface is projected onto the stage. The portable overhead projector according to claim 1, wherein a Fresnel lens for condensing light is provided on the lens, and the image projection sheet is placed on the Fresnel lens. 3. The portable overhead projector according to claim 2, wherein the Fresnel lens has a thickness of 1 mm or less. 4. The portable overhead projector according to claim 2, wherein a duct for circulating cooling air for cooling the light source is provided in the projection unit. 5. A portable overhead projector comprising a projection unit, a stage base, and an arm part, wherein the projection unit and the stage base are folded and housed in the arm part. 6. A portable overhead projector comprising a projection unit, a stage base and an arm part, wherein the projection unit and the arm part are housed in the stage base. 7. The projection unit, the stage base, and the arm portion are foldably attached to each other, and the projection unit and the arm portion are folded and stored in the stage base. Portable overhead projector. 8. The portable overhead projector according to claim 6, wherein the arm portion is configured to be extendable and retractable, and the projection portion is housed in the stage base by contracting the arm portion. 9. An image forming sheet of a notebook size or smaller, which is removably attached to a mount for printer printing or a copying machine, forms an image on the image forming sheet and is used as an image projecting sheet. A portable overhead projector characterized in that