JP2001025036A - Stereoscopic image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively reduce the rotation driving force of a screen and to reduce a cost. SOLUTION: The gap Ga between a rotary disk 39 and a fixed wall surface FL on the side of an enclosure 20a is set as small as possible within the range that the rotary disk 39 can be smoothly rotated, and the inside of the enclosure 20a is almost tightly closed. Then, a motor 74 is driven and the rotary disk 39 and the screen 38 are rotated through a belt 78. At the time, since the inside of the enclosure 20a is almost tightly closed, air moves only in a direction along the inner wall of the enclosure 20a and the eddy air flow is generated in the rotating direction of the screen 38. Thus, load for the rotation driving of the screen 38 is reduced and also the driving power of the motor 74 is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stereoscopic image display apparatus using a screen rotation system.

[0002]

BACKGROUND OF THE INVENTION As one of the methods for displaying a stereoscopic image, there is a volume scanning method utilizing the afterimage effect of the human eye.

In such a volume scanning method, a rotatable screen is rotated at a high speed around a predetermined rotation axis, and a two-dimensional image of a cross section of an object or a contour of the cross section changes momentarily according to the rotation angle of the screen. And projecting. In this case, an enclosure covering the screen is required to prevent the observer from touching the high-speed rotating screen.

[0004]

2. Description of the Related Art In the above-described volume scanning method, since a plate-like screen needs to be rotated at a high speed, there is naturally a problem of air resistance. In other words, in order to realize high-speed rotation against air resistance, a large output is required for a motor serving as a driving source, so that energy consumption is increased, or a larger motor is required to obtain a corresponding output. You have to choose.

Therefore, a technique conventionally used for reducing the air resistance is disclosed in, for example, JP-A-6-2736.
No. 93 is disclosed. Here, the following two devices are described.

[0006] In the first device, a plurality of slits as exhaust holes are provided in the outer peripheral portion of the enclosure covering the rotating screen. When the screen rotates inside the fixed enclosure, the air in the enclosure is exhausted from the slits, the air pressure in the enclosure decreases, and the air resistance to the screen decreases, so that energy consumption can be reduced.

In the second device, the screen is housed in a sealed enclosure, and the screen and the enclosure are rotated integrally. According to this configuration, air resistance occurs only between the enclosure and the outside atmosphere,
Moreover, since the enclosure has a rotationally symmetric shape, air resistance can be reduced.

[0008]

However, the first device has the following problems. That is, since a plurality of slits as exhaust holes are provided, a flow of air is generated between the inside and the outside of the enclosure due to a change in pressure generated in the enclosure in response to the rotation of the screen. That is, air flows from the inside of the exhaust hole to the outside on the front surface in the screen moving direction where the pressure is high, and from the outside of the exhaust hole to the inside on the rear surface in the screen moving direction where the pressure is low. This generates an irregular turbulent flow which is perpendicular to the direction of movement of the screen surface (the circumferential direction of rotation), and imposes a load on the rotation of the screen. Then, the energy consumption required for rotating the screen is increased. Further, since the refraction of light is different between the slit portion and the portion other than the slit, a discontinuous image is formed at the boundary, and the quality of the observed image may be reduced. Further, when a plurality of slits are provided, the appearance of the device is deteriorated.

On the other hand, the second device has the following problems. That is, since the enclosure itself that houses the screen rotates, the enclosure cannot play a role of protecting the observer from an object that rotates at a high speed. Therefore, it is necessary to further cover the outside of the enclosure with a single transparent cover in order to ensure safety. This leads to an increase in cost, and there is a possibility that the quality of an image to be observed may be reduced due to the influence of the transparency of the cover and the multiple reflection on the surface of the cover.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and can effectively reduce the rotational driving force of the screen, reduce the cost, and degrade the quality of the observed image. It is an object of the present invention to provide a three-dimensional image display device that does not have any problem.

[0011]

According to a first aspect of the present invention, there is provided a three-dimensional image display apparatus for displaying a three-dimensional image by a volume scanning method utilizing an afterimage effect. A screen rotatable about a central axis parallel to a plane, (b) projection optical means for projecting a cross-sectional image of a display object corresponding to a rotation angle of the screen on the screen, and (c) the central axis. A hollow enclosure having an opening at one end side of the screen and arranged so as to cover the rotation space of the screen, and (d) sealing means for substantially sealing the opening, the enclosure comprising: At least a part is transparent and a part other than the opening is in an airtight state, and an airflow generated in the rotating space by the rotation of the screen is blocked by an inner wall of the enclosure.

According to a second aspect of the present invention, in the three-dimensional image display device according to the first aspect of the present invention, the screen is substantially rectangular, and the enclosure has a substantially cylindrical shape having a cross section corresponding to a plane size of the screen. It is a shape.

According to a third aspect of the present invention, in the stereoscopic image display device according to the first or second aspect of the present invention, a gap between an outer periphery of the rotating space and an inner wall of the enclosure is a maximum of the screen. It is 10% or less of the turning radius.

According to a fourth aspect of the present invention, in the stereoscopic image display apparatus according to any one of the first to third aspects, the sealing means is arranged near the opening of the enclosure, and And a sealing means for sealing between the rotating disk and a fixed wall surface on the enclosure side.

According to a fifth aspect of the present invention, in the three-dimensional image display device according to the fourth aspect of the present invention, the sealing means comprises:
A labyrinth seal formed on an outer peripheral portion of the rotating disk and / or the fixed wall surface.

According to a sixth aspect of the present invention, in the stereoscopic image display apparatus according to the fourth aspect of the present invention, the sealing means comprises:
An elastic seal inserted between an outer peripheral portion of the rotating disk and the fixed wall surface.

According to a seventh aspect of the present invention, in the stereoscopic image display apparatus according to any one of the first to third aspects, the sealing means is connected to the enclosure and has a window communicating with the opening. And the housing is hermetically sealed at a portion other than the window, and rotation driving means for the screen is housed in the housing.

According to an eighth aspect of the present invention, in the stereoscopic image display device according to any one of the fourth to seventh aspects, the rotating space is reduced to an atmospheric pressure or less.

According to a ninth aspect of the present invention, in the stereoscopic image display device according to any one of the first to third aspects, the sealing means is arranged near the opening of the enclosure, and A rotating disk that rotates with, and a substantial air leak exists between the rotating space and the external space of the device via a gap between the fixed wall surface on the enclosure side and the rotating disk. The apparatus further includes a pressure reducing unit configured to reduce the pressure of the rotating space to the atmospheric pressure or less.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS * <First Embodiment><A. Overall System Configuration> FIG. 1 shows an overall configuration of a stereoscopic image display system using a stereoscopic image display device according to an embodiment of the present invention. This stereoscopic image display system 1
A three-dimensional image display device 100 that performs three-dimensional display of a display object by a volume scanning method of rotational scanning, a host computer 3 that supplies two-dimensional image data relating to a cross-sectional image of the display object to the three-dimensional image display device 100, It is composed of

The three-dimensional image display device 100 generates an afterimage effect by intermittently projecting a cross-sectional image of a display object on a screen that rotates at a high speed about a predetermined rotation axis, as described later. Display an image. Then, by updating the cross-sectional image to be projected according to the position (angle) of the rotating screen, three-dimensional images of various display objects are displayed.

The host computer 3 is a so-called general computer system including a CPU 3a, a display 3b, a keyboard 3c, and a mouse 3d. The host computer 3 incorporates software for performing a process of generating two-dimensional image data of a cross-sectional image corresponding to each angle when the screen is rotated from three-dimensional image data of a display object input in advance. I have. For this reason, the host computer 3 can generate two-dimensional image data relating to a cross-sectional image of the display object to be projected on the screen according to the rotation angle of the screen from the three-dimensional image data of the display object, and generate the same. The obtained two-dimensional image data is supplied to the three-dimensional image display device 100.

Between the host computer 3 and the three-dimensional image display device 100, data can be transferred online, and data can be transferred offline via a portable recording medium 4.
Examples of the recording medium 4 include a magneto-optical disk (MO), a compact disk (CD-RW), a digital video disk (DVD-RAM), and a memory card.

<B. Stereoscopic Image Display> Next, the stereoscopic image display 100 of the first embodiment will be described. FIG.
1 is a diagram showing an overview of a stereoscopic image display device 100. FIG. The three-dimensional image display device 100 is provided on a housing 20 having a built-in optical system for projecting a cross-sectional image on a rectangular screen 38 and a control mechanism for performing various data processing, and provided on an upper side of the housing 20. A hollow enclosure 20a for accommodating a rotating screen therein.

The enclosure 20a is made of a transparent material such as glass or acrylic resin, and is configured so that a cross-sectional image projected on a screen 38 rotating on the inside can be visually recognized from the outside. The enclosure 20a has a cylindrical shape having a cross section corresponding to the plane size of the screen 38. In addition,
At least a part of the enclosure 20a may be made of a transparent material. For example, the front half may be made of a transparent material, and the rear half may be made of an opaque material. Further, as described later, the internal space of the enclosure 20a is substantially closed.

A liquid crystal display (LCD) 21, a detachable operation switch 22, and a detachable opening 23 for the recording medium 4 are arranged on the front side of the housing 20, and a digital input / output terminal 24 is provided on the side. ing. The liquid crystal display 21 is provided with a display means for displaying an operation guide screen when performing an operation input, and a display means 2 for indexing a display object.
It is used as a means for displaying a two-dimensional image. The digital input / output terminal 24 is a SCSI terminal, an IEEE1394 terminal, or the like. Further, speakers 25 for outputting sound are arranged at four places on the outer peripheral surface of the housing 20. The housing 20 is not particularly configured to be airtight.

FIG. 3 is an enlarged view of the detachable operation switch 22. The operation switch 22 functions as an operation input unit for inputting various operation parameters. The power button 221, the start button 222, the stop button 223, the cursor button 224, the select button 225, the cancel button 226, the menu button 2
27, various buttons such as a zoom button 228 and a volume control button 229 are arranged.

The display of a stereoscopic image on the screen 38 is as follows.
By operating the buttons 221 to 227 of the operation switch 22, two-dimensional image data to be displayed in a three-dimensional manner is selected from a data file recorded on the recording medium 4 or data stored in the host computer 3. It starts by selecting two-dimensional image data from a file.

Next, an optical system for projecting a sectional image on the screen 38 in the three-dimensional image display device 100 will be described. FIG. 4 is a diagram showing a configuration including an optical system in the stereoscopic image display device 100. As shown in FIG. 4, the optical system in the stereoscopic image display device 100 includes an illumination optical system 40, a projection optical system 50, a DMD (digital micromirror device) 33, and a TIR prism 44.

First, the DMD 33 will be described. DM
D33 functions as an image generation unit that generates a cross-sectional image to be projected on the screen 38.
It has a structure in which an extremely small mirror of a rectangular metal piece (for example, an aluminum piece) of about μm is laid out on a plane with a scale of several hundred thousand per chip as one pixel, and a static output of the SRAM output arranged immediately below each pixel. This device is capable of individually controlling the tilt angle of each mirror at ± 10 degrees by the action of an electric field. The mirror angle control is an ON / OFF binary control corresponding to the SRAM output “1” or “0”, and is turned ON (or OF) when light from the light source is applied.
Only the light reflected by the mirror facing the direction F) travels toward the projection optical system 50, and the light reflected by the mirror facing the OFF (or ON) direction deviates from the effective optical path. Do not go in the direction of. ON this mirror
By the / OFF control, a cross-sectional image corresponding to the ON / OFF mirror distribution is generated and projected on the screen 38.

The direction of the reflected light is switched by controlling the tilt angle of each mirror. By adjusting the switching time (the length of the reflected time), the density (gradation) of each pixel can be expressed. Thus, 256 gradations can be expressed for one color. Then, R that periodically switches white light from the light source
(Red), G (green), and B (blue) color filters to form a color image by synchronizing the DMD chip with each of the passed colors, or forming a color image for each of R, G, and B colors
A color image can be formed by preparing an MD chip and simultaneously projecting three colors of light.

The DMD 33 generates one image because the response of the deflection of each mirror is about 10 μsec and the writing of image data can be performed in substantially the same manner as a general SRAM. 1ms required
Very fast, c or less. Temporarily 1ms
ec, 1/1 to realize the afterimage effect.
When performing a volume scan of 180 ° (ie, 9 rotations per second) in 8 seconds, the number of cross-sectional images that can be generated is about 60. Compared to CRTs and liquid crystal displays used as image generation means in the conventional volume scanning method, DMD
The unit 33 can project a much larger number of cross-sectional images on the screen 38 per unit time, and can also display a non-rotationally symmetric solid.

As shown in FIG. 4, on the image generation surface side of the DMD 33, the illumination light from the illumination optical system 40 is guided to each micro mirror, and the cross-sectional image generated by the DMD 33 is guided to the projection optical system 50. For this purpose, a TIR prism 44 is provided.

The illumination optical system 40 has a white light source 41 and an illumination lens system 42, and illumination light from the white light source 41 is converted into parallel light by the illumination lens system 42. The illumination lens system 42 includes a condenser lens 421 and an integrator 42.
2, a color filter 43 and a relay lens 423. Illumination light from the white light source 41 is condensed by the condenser lens 421 and enters the integrator 422. Then, the illumination light whose light amount distribution is made uniform by the integrator 422 is separated into any one of R, G, and B color components by the rotary color filter 43. The split illumination light is converted into parallel light by the relay lens 423, and then enters the TIR prism 44.
Irradiated on DMD 33.

The DMD 33 projects only the light component of the illumination light necessary for projecting a cross-sectional image by changing the inclination angle of each micromirror based on the two-dimensional image data given from the host computer 3. Optical system 5
Reflect toward zero.

The projection optical system 50 has a projection lens system 51 and a screen 38. The projection lens system 51 includes two telecentric lenses 511, a projection lens 513, projection mirrors 36 and 37, and an image rotation compensating mechanism 34.
Among them, the projection lens 513 and the projection mirrors 36 and 37 are arranged inside a rotating disk 39 for rotating the screen 38 around the rotation axis Z.

The light (cross-sectional image) reflected by the DMD 33 is converted into parallel light by the two telecentric lenses 511.
The image passes through the image rotation compensating mechanism 34 in order to compensate for the rotation of the cross-sectional image. The light beam whose rotation has been compensated by the image rotation compensating mechanism 34 is projected onto the projection mirror 36 and the projection lens 51.
3. Finally, the screen 38 via the projection mirror 37
Is projected on the main surface (projection plane) of the.

In this optical system, the projection mirror 36, the projection lens 513, the projection mirror 37, and the screen 38 are fixed to a rotating disk 39, and the rotation of the rotating disk 39 causes a vertical rotation including the central axis of the screen 38. It rotates around the axis Z at an angular velocity Ω. That is, when the screen 38 is rotated to perform volume scanning, the rotating disk 39 is rotated.
Since the projection mirror 36, the projection lens 513, and the projection mirror 37 disposed inside also rotate integrally with the screen 38, it is possible to always project a cross-sectional image from the front side regardless of the angle of the screen 38. You can.

The rotation angle of the screen 38 is always detected by the position detector 73.

The cross-sectional image generated in the DMD 33 is projected on the screen 38. Projection lens 5
The role of 13 is to ensure that the light flux has the proper image size everywhere on the screen 38. Also,
The projection mirror 37 is positioned obliquely downward in front of the screen 38 (in the case of FIG. 4, a rotating disk 39) so as not to obstruct the line of sight of the observer when observing the three-dimensional image projected on the screen 38.
Are arranged so as to project a cross-sectional image from the inside side. The projection mirrors 36 and 37 of the projection lens 513
Is not necessarily limited to this embodiment.

Here, the image rotation compensating mechanism 34 will be described. The image rotation compensating mechanism 34 shown in FIG. 4 is realized by a so-called image rotator. When the rotating disk 39 to which the screen 38 is attached is located at a certain rotation angle, the cross-sectional image projected on the screen 38 is used as a reference image. If the image rotation compensating mechanism 34
Is not used, the cross-sectional image projected as the rotating disk 39 rotates rotates in the plane on the screen 38, and the cross-sectional image projected when the rotating disk 39 rotates 180 ° moves up and down with respect to the reference image. Will be the reversed image.
The image rotation compensating mechanism 34 prevents this phenomenon.

The image rotation compensating mechanism 34 shown in FIG. 4 uses an image rotator constituted by combining a plurality of mirrors. When the image rotator is rotated around the optical axis, the emitted image with respect to the incident image is rotated at an angular velocity twice as high as the angular velocity of the image rotator and emitted. Therefore, by rotating the image rotator at an angular velocity of half the angular velocity of the rotating disk 39 to which the screen 38 is attached, an upright sectional image can be always projected regardless of the rotation of the screen.

The same effect can be obtained by using a dub (type) prism other than the image rotator as the image rotation compensating mechanism. Also, without using the image rotation compensating mechanism 34 described here, the rotation of the projected image is performed by using a cross-sectional image generated on the surface of the DMD 33 as an image that rotates around the optical axis according to the rotation angle of the screen 38. You may cancel.

That is, the cross-sectional image generated on the surface of the DMD 33 is an upright image (or an inverted image) at the start of the volume scan, and rotates when the screen 38 rotates to complete the volume scan. The two-dimensional image data for generating the cross-sectional image may be corrected at a stage before being given to the DMD 33 so as to be (or an erect image).

Here, the screen 38 and the rotating disk 3
FIG. 5 shows an example of a perspective overview view of No. 9. As shown in FIG. 5, the rotating disk 39 has a disk shape, and is rotationally driven via a belt 78 wound around a rotating shaft of a motor 74 serving as a rotational driving means. The rotation may be performed by bringing the rotating shaft of the motor 74 into contact with the side surface of the rotating disk 39. Further, a motor may be directly connected to the central axis of the rotating disk 39, or may be driven via a gear or a chain.

When the screen 38 is at a certain rotation angle θ1 as shown in FIG. 5, a sectional image P1 (generated by the DMD 33) of the display object corresponding to θ1 is formed by the projection mirror 36 and the projection lens 513 shown in FIG. And projected on a screen 38 via the projection mirror 37. When the screen 38 rotates for a short period of time and the rotation angle becomes θ2, a cross-sectional image P2 of the display object corresponding to θ2 (generated by the DMD 33) is projected as shown in FIG. The light is projected onto the screen 38 via the mirror 36, the projection lens 513, and the projection mirror 37.

Since the projection mirror 36, the projection lens 513, and the projection mirror 37 rotate together while maintaining a fixed positional relationship with respect to the screen 38, a cross-sectional image is always projected on the screen 38 regardless of the rotation. When the rotating disk 39 is rotated 180 ° (or 360 °), the same cross-sectional image appears again, and one volume scan is completed. The above operation is performed by increasing the rotation speed of the rotating disk 39 sufficiently fast so that an afterimage effect occurs and by sufficiently increasing the number of cross-sectional images to be projected. A three-dimensional image can be visually recognized. FIGS. 6 and 7 conceptually show how a stereoscopic image is displayed by rotating the screen 38 and projecting the cross-sectional image.

<C. Control Mechanism in Stereoscopic Image Display System> Next, a control mechanism for displaying a stereoscopic image in the stereoscopic image display system 1 will be described.

FIG. 8 is a block diagram showing a functional configuration of the stereoscopic image display system 1. In FIG. 8, solid arrows indicate the flow of electric signals, and broken arrows indicate the flow of light.

The two-dimensional image data relating to the cross-sectional image of the display object is input from the host computer 3 to the interface 66 via the digital input / output terminal 24,
Alternatively, it is input from the recording medium 4 to the interface 66.

Generally, image data has a larger data amount than other types of data, and thus data compression is often performed. Therefore, a data decompressor 65 for decompressing the compressed two-dimensional image data is provided.

The expanded two-dimensional image data is DMD3
Drive unit 60 for controlling the generation of the cross-sectional image in the third section
Given to. The DMD driving unit 60 includes the DMD 33 and the DMD
A controller 62 and a memory 63 are provided. The memory 63 stores a plurality of two-dimensional image data. The DMD controller 62 supplies a gradation signal to the DMD 33, controls a driver 71 for driving the color filter 43 in accordance with the rotation angle of the screen 38 detected by the position detector 73, and performs a write operation in the memory 63. And the read operation.

The system controller 64 gives a drive command to a screen controller 72 for controlling the rotation operation of the image rotation compensation mechanism 34 and the operation of the motor 74 in the projection lens system 51. The system controller 64 controls the driver 70 that drives the white light source 41,
The interface 66 and the data decompressor 65 are managed and controlled, and the state of supply of the two-dimensional image data to the DMD driver 60 and the like are transmitted to the DMD controller 62.

The system controller 64 gives an instruction to the character generator 69 to display appropriate characters and symbols on the screen of the liquid crystal display 21 and also inputs information from the detachable operation switch 22. Is also configured to be able to be input. The operation switch 22 and the three-dimensional image display device 100 are configured to perform infrared communication. The three-dimensional image display device 100 has a transmission / reception unit 75a for infrared communication and a driver 75b. Is the transmission / reception unit 7
6a and a driver 76b.

The audio data included in the two-dimensional image data is restored by an audio decoder (not shown) provided inside the data decompressor 65, and the obtained audio data is converted into a D / A converter 68a and an amplifier section. 68b and output from the speaker 25. Power supply 6
7 supplies power to each part of the stereoscopic image display device 100 shown in FIG.

<D. Details of Configuration for Substantially Sealing Inside Enclosure> FIG. 9 corresponds to a configuration in which an enclosure 20a is added to the rotation mechanism of the screen 38 shown in FIG. 5, and a configuration that substantially seals the internal space of the enclosure 20a. FIG. This figure shows a cross section including the rotation axis 38c of the screen 38 and perpendicular to the main surface of the screen 38. However, the optical system shown in FIG. 4 is omitted.

Rotating disk 39 for fixing screen 38
Is rotationally driven by a motor 74 via a belt 78 as a transmission member. Also, the rotation axis 38 of the screen 38
c and the center of rotation of the rotating disk 39 are made to coincide with each other. In addition, this matching is performed to suppress eccentricity,
There may be some deviation. Then, by driving the motor 74, the screen 38 is moved to the enclosure 20.
a, and scans the volume of the cylindrical rotating space Vs.

The enclosure 20a is connected to and fixed to the housing 20 at its lower part. Except for the opening at the lower end, which is necessary and sufficient for coupling to the housing 20, holes and notches are provided in the wall surface WL of the enclosure 20a so that air can flow between the inside and the outside of the enclosure 20a. This enclosure 20
The wall surface WL of a is in an airtight state.

Further, the rotating disk 39 and the enclosure 2
The gap Ga with the fixed wall surface FL on the 0a side (in the illustrated example, the inner wall surface of the housing 20) has a constant width over the entire outer periphery of the rotating disk 39, and is possible within a range where the rotating disk 39 can rotate smoothly. Although it is set as small as possible, it is desirably set to be smaller than the flow path length of the air flow leaking through the gap Ga, that is, the thickness t of the rotating disk 39 in the case of this embodiment. In terms of the size of the screen 38, the gap Ga is preferably half the width of the screen 38 in the direction perpendicular to the rotation axis 38c of the screen 38, that is, 10% or less of the maximum rotation radius Rmax. In addition, it is better if it is 5% or less.

According to the above configuration, the space Vs which is scanned by the rotation of the screen 38 has a space Vs.
a, the housing 20, and the rotating disk 39 form a substantially closed space. Therefore, in the apparatus of this embodiment, the rotating disk 39 functions as a sealing means for substantially sealing the opening at the lower portion of the enclosure 20a.

FIG. 10 is a sectional view as viewed from the position XX in FIG. Regarding the gap Gb between the outer periphery of the rotation space Vs of the screen 38 and the inner wall of the enclosure 20a,
As in the case of a, the rotating disk 39 is set to be as small as possible within a range in which the rotating disk 39 can rotate smoothly, but is desirably set to be smaller than the thickness t of the rotating disk 39. The gap Gb is preferably half the width of the screen 38 in the direction perpendicular to the rotation axis 38c, that is, 10% or less, more preferably 5% or less with respect to the maximum rotation radius Rmax (FIG. 9).

FIG. 11 is a sectional view corresponding to FIG. 9 of the screen 38r having a substantially semicircular main surface. As shown in this figure, when the distance from the central axis to the outer periphery of the rotating space Vsr is not constant, the above-mentioned maximum turning radius refers to the maximum distance rmax from the central axis at the outer periphery of the rotating space Vsr. Become. Further, the inner wall shape of the enclosure 20r has a substantially hemispherical shape that is substantially similar to the outer periphery of the rotation space Vsr of the screen 38r.

<Operation of Stereoscopic Image Display Device 100> The operation of the stereoscopic image display device 100 having such a configuration is as follows.

First, after the observer (operator) performs an operation of writing two-dimensional image data from the recording medium 4 or the like to the memory 63, the start button 22 of the operation switch 22
Press 2. As a result, the screen 38 is
The rotation is started around 8c, the two-dimensional image data is sequentially read from the memory 63, and the cross-sectional image is projected on the rotating screen 38. As a result, a three-dimensional image using the afterimage effect is displayed.

The rotation operation of the screen 38 is shown in FIG.
This will be described with reference to FIG. Locally, the air flow Fa pushed out to the screen 38 rotating in the direction Ds is blocked by the inner wall of the enclosure 20a, and the direction of the flow is changed to Fb. That is, the enclosure 20
Since the air in a is substantially sealed and confined in the internal space of the enclosure 20a, it can only move in the direction along the inner wall of the enclosure 20a. After some time from the start of rotation, the direction Da
, A vortex flow of air around the rotation shaft 38c is generated. Here, the turbulent air flow generated in the slit in the related art does not occur, and the air flow becomes almost laminar. Then, the airflow component in a direction different from the rotation direction of the screen 38 decreases, and the screen 38
The load expended besides the rotational drive of the motor can be reduced, and the motor 7
4 power can be reduced.

Further, since the internal air moves in the rotation direction of the screen 38, the relative speed between the air and the screen 38 is reduced, and the wind noise generated at the time of the collision can be reduced.

Further, since the enclosure 20a is stationary, there is no need to provide a transparent cover or the like outside the enclosure 20a, so that an increase in cost can be prevented.

Since the enclosure 20a is not provided with a slit or the like and there is no need to provide an additional transparent cover as described above, visual obstruction occurs when observing a stereoscopic image projected on the rotating screen. The quality of the image can be maintained with few changes.

Furthermore, image data for generating a rotated image is often created on the premise of a rectangular image area. In the apparatus of this embodiment, the screen 38 has a rectangular shape corresponding thereto. At the same time, the enclosure 20a has a cylindrical shape. Therefore, a clearance (gap G) between the rotation space Vs of the screen 38 and the enclosure 20a for preventing collision between them is provided.
There is little extra space other than b), and no power is required to generate or maintain an airflow in such extra space.

The inventor of the present invention conducted experiments on three cases as shown in FIGS. 17A to 17C in order to verify such a principle. Of these, FIG.
Fig. 17 (b) shows a case without an enclosure.
FIG. 17C shows a case where an enclosure having an open upper surface and covering only the side surface (hereinafter, “side-type enclosure”) is provided. FIG. Full enclosure ”) is used.

In FIG. 17 (c), for the sake of experiment, a substantially sealed state is realized by mounting a plate on an enclosure having an open upper surface, but is aerodynamically similar to the embodiment of FIG. It has a structure.

As a result of the experiment, as shown in the graph of FIG. 17, the electric power (expressed in terms of current) required for driving the motor 74 is almost the same as that without the enclosure in the side type enclosure, In this case, the power consumption is slightly reduced as compared with the case without the enclosure.

On the other hand, in the case of the almost complete enclosure, significantly less power is required in both the case without the enclosure and the case with the side-type enclosure over a wide range of rotation speed. . From this, it can be seen that the use of a substantially complete enclosure greatly contributes to power saving.

* <Second Embodiment> A stereoscopic image display device according to a second embodiment of the present invention is similar to the configuration of the first embodiment, but differs in the configuration for sealing the rotating disk. .

FIG. 12 shows an apparatus according to the second embodiment.
FIG. 10 is an enlarged cross-sectional view corresponding to a state where a region A surrounded by a virtual line in FIG. 9 is replaced. Further, the region A ′ in FIG. 9 has a structure as shown in FIG.

In the surface of the rotating disk 39A corresponding to the rotating disk 39 of the first embodiment, three grooves 39h are provided on the outer peripheral surface facing the housing 20 so as to surround the rotating disk 39A. Is made to change suddenly periodically. Such a structure, that is, the labyrinth seal 39s has a greater resistance to the flow of the fluid in the gap than the gap Ga having a constant width shown in the first embodiment. This labyrinth seal 39s
It functions as sealing means for sealing between the rotating disk 39A and the enclosure 20a. Therefore, screen 3
The degree of sealing of the space that is scanned by the rotation of the volume 8 is higher than in the first embodiment.

In FIG. 12, the groove 3 is formed on the rotating disc 39A side.
Although three 9h are provided, one or more grooves may be provided, and this groove may be provided on the housing 20 side, or may be provided on both the rotating disk 39A side and the housing 20 side. The shape of the groove 39h is not necessarily a triangle, but may be a quadrangle, an arc, or the like.

The basic operation and effects of the stereoscopic image display device of the second embodiment are the same as those of the first embodiment. In the case of the second embodiment, the labyrinth seal 39s is used to increase the degree of sealing compared to the first embodiment, so that the power of the motor 74 can be further reduced.

* <Third Embodiment> A stereoscopic image display device according to a third embodiment of the present invention is similar to the configuration of the first embodiment, but differs in the configuration for sealing the rotating disk. .

FIG. 13 shows an apparatus according to the third embodiment.
FIG. 10 is an enlarged cross-sectional view corresponding to a state where a region A surrounded by a virtual line in FIG. 9 is replaced. The cross section of the region A ′ in FIG.
It becomes symmetrical with 3.

A rubber seal as an elastic seal is provided between the outer peripheral portion of the rotary disk 39B corresponding to the rotary disk 39 of the first embodiment and the fixed wall surface FL (the inner wall surface of the housing 20 in the illustrated example) on the enclosure 20a side. Packing 39 made of
p is inserted. The packing 39p has a rotating disc 3
It is configured such that pressing force is applied from both the 9B and the housing 20. The packing 39p is elastically deformed by the pressing load, and comes into close contact with the rotating disk 39B and the housing 20, respectively. As a result, the space scanned by the rotation of the screen 38 is completely sealed. Here, the packing 39p is connected to the rotating disc 39.
Which side of the housing B or the housing 20 is fixed is arbitrary, but is fixed to the rotating disk 39B side in the apparatus of FIG. Therefore, in this example, the outer periphery of the packing 39p slides on the fixed wall surface FL.

The packing 39p may be made of resin, metal, or the like, and its shape is not limited to FIG. Further, a plurality of packings may be arranged, and in this case, the reliability of the sealing degree is improved. further,
Lubricating oil may be applied or supplied to the sliding portion to reduce the wear of the packing 39p.

The basic operation and effect of the three-dimensional image display device of the third embodiment are the same as those of the first embodiment. Also,
The packing 39 is different from the first embodiment and the second embodiment.
Since the internal space of the enclosure 20a is completely sealed by using p, the power of the motor 74 can be further reduced.

Further, by discharging the air in the enclosure 20a and reducing the pressure to below the atmospheric pressure to reduce the density of the internal gas, the air resistance applied to the rotating screen 38 can be further reduced. Thereby, the power of the motor 74 can be further reduced. Here, even if the degree of vacuum is reduced to some extent during the stereoscopic image display due to deterioration of the packing 39p or the like, the rotation number of the screen 38 detected by the position detector 73 is fed back to the motor 74. It does not decline. Note that the above-described decompression is performed at the time of assembling the stereoscopic image display device.

Further, as shown in FIG. 14 (the mechanism such as the optical system in the housing 20 is omitted), if the housing 20 has a structure capable of maintaining the airtight state of the portion other than the window 20w connected to the enclosure 20a, the housing 20 By connecting the enclosure 20 and the enclosure 20a,
The inside of these can be airtight. Therefore, the packing 39p required for sealing inside the enclosure 20a becomes unnecessary, and the configuration can be simplified. Also in this case, the air resistance applied to the rotating screen 38 can be further reduced by reducing the pressure in the enclosure 20a to the atmospheric pressure or less.

In the case of the configuration shown in FIG. 14, a wiring 80 from the motor 74 and various control circuits is provided between the internal space of the combined body of the enclosure 20a and the housing 20 and the external space of the apparatus. Just connect them. In this case, it is relatively easy to increase the airtightness of the portion where the wiring 80 penetrates the housing 20, and there is an advantage that the hermeticity of the internal space is improved.

* <Fourth Embodiment> A stereoscopic image display apparatus according to a fourth embodiment of the present invention is similar to the configuration of the third embodiment, but as shown in FIG. Evacuation pump 79 to discharge
Is added.

The pressure reducing pump 79 is connected to the enclosure 20a.
The air in the enclosure 20a can be exhausted and reduced in pressure through a pipe 79t connected to the air conditioner. In the third embodiment, the decompression inside the enclosure 20a is possible only during the assembling, but in the present embodiment, even after the assembling, the pressure can be appropriately reduced by starting the pump 79.

The basic operation and effects of the stereoscopic image display device of the fourth embodiment are the same as those of the third embodiment. As in the third embodiment, since the seal is completely sealed by the packing 39p, the power of the motor 74 can be further reduced. Further, a vacuum pump 79 controls the enclosure 20.
A screen 38 that can reduce the pressure inside
Can be further reduced, and the power of the motor 74 can be reduced.

The decompression pump 79 may be started continuously during the display of the stereoscopic image, or may be started for a predetermined time before the display of the stereoscopic image. Alternatively, when the accumulated time of the stereoscopic image display operation is measured and reaches a predetermined accumulated time, the operation may be automatically started.

Further, the packing 39p may be removed, and the pressure reducing pump 79 may be activated during the stereoscopic image display operation to reduce the pressure in the enclosure 20a to the atmospheric pressure or less. In this case, since the packing 39p has been removed, the housing 2
Although there is air inflow through the gap between the rotating disk and the rotating disk, by reducing the gap, the inflow can be relatively reduced. , The pressure inside can be reduced. Therefore, the air resistance can be reduced, and the power of the motor 74 can be reduced.

* <Modifications> ◎ In each embodiment such as FIG. 9, the fixed wall surface FL facing the outer peripheral surface of the rotating disk 39 is the inner wall surface of the housing 20, but the inner wall surface of the enclosure 20a is the rotating circular surface. When facing the outer peripheral surface of the plate 39, the enclosure 20a
The inner wall surface becomes the “fixed wall surface on the enclosure side”. Therefore, in this case, the preferred range of the size of the gap Ga and the description of the position where the sealing means is provided apply to the gap between the rotating disk 39 and the inner wall surface of the enclosure 20a.

That is, the "enclosure-side fixed wall surface" in the inventions of claims 4 to 6 corresponds to the fixed wall surface facing the outer periphery of the rotating disk, and is necessarily the inner wall surface of the enclosure 20a itself. No need.

In each embodiment, a seal is provided near the outermost periphery of the rotating disk 39, but this is not essential. For example, as shown in FIG.
And a seal may be provided near the outer periphery of the cylindrical portion 39m. In this case, since the peripheral speed at the outer periphery of the cylindrical portion 39m is smaller than the outermost periphery of the rotating disk 39,
Wear of packing and the like can be suppressed.

In the second embodiment, a labyrinth seal is not essential, and a seal system such as a mechanical seal may be used.

In the third embodiment, instead of reducing the density of the internal gas by reducing the pressure in the enclosure 20a, a gas lighter than air, for example, helium gas, is sealed to reduce the resistance associated with the rotation of the screen 38. May be. Thus, as in the case of reducing the pressure, the load for driving the screen 38 to rotate can be reduced, and the power of the motor 74 can be reduced.

[0097]

As described above, according to the first aspect of the present invention, the hollow enclosure and the opening which are stationary so as to cover the rotating space of the screen with the opening are substantially sealed. Sealing means, at least a part of the enclosure is transparent and a part other than the opening is in an airtight state, and an airflow generated in the rotating space by rotation of the screen is blocked by an inner wall of the enclosure. As a result, unnecessary airflow other than the airflow along the inner wall of the enclosure in the substantially closed space is rarely generated, and the rotational driving force of the screen can be effectively reduced. No slits etc. are formed in the enclosure,
Since an external transparent cover is not required, the quality of an image to be observed is not impaired, and an increase in cost due to the addition of an external transparent cover can be prevented.

According to the second aspect of the present invention, in response to the fact that image data is often supplied on the basis of a rectangular image area, the screen is made substantially rectangular, and the enclosure is reduced to the screen plane size. Since it is a substantially cylindrical shape with a corresponding cross section, there is little extra space between the rotating screen and the inner wall of the enclosure, airflow along the inner wall of the enclosure is effectively generated, and the rotational driving force of the screen is increased. Can be reduced.

According to the third aspect of the present invention, the gap between the outer periphery of the rotating space and the inner wall of the enclosure is set to be 10% or less of the maximum radius of rotation of the screen, so that the airflow along the inner wall of the enclosure is effectively prevented. And the rotational driving force of the screen can be further reduced.

According to the fourth aspect of the present invention, the sealing means is disposed near the opening of the enclosure and has sealing means for sealing between the rotating disk and the fixed wall surface on the enclosure side. The degree of airtightness can be increased.

According to the fifth aspect of the present invention, since the sealing means is a labyrinth seal formed on the outer peripheral portion of the rotating disk and / or on the fixed wall surface, the sealing in the enclosure can be easily realized.

According to the sixth aspect of the present invention, since the sealing means is an elastic seal inserted between the outer peripheral portion of the rotating disk and the fixed wall surface, the degree of sealing in the enclosure can be further increased. .

According to the seventh aspect of the present invention, the sealing means includes a housing connected to the enclosure and having a window communicating with the opening, and the housing is formed airtight at portions other than the window and rotates the screen. The driving means is housed in the housing. As a result, the configuration for sealing the inside of the enclosure can be simplified.

According to the eighth aspect of the present invention, since the rotating space is reduced to the atmospheric pressure or less, the air resistance can be reduced, and the rotational driving force of the screen can be further reduced.

According to the ninth aspect of the present invention, the sealing means is provided near the opening of the enclosure and includes a rotating disk which rotates together with the screen, and is provided with a gap between the fixed wall surface on the enclosure side and the rotating disk. A substantial air leak exists between the rotating space and the external space of the apparatus, and the apparatus further includes a decompression means for reducing the pressure of the rotating space to the atmospheric pressure or less. As a result, the air resistance can be reduced, and the rotational driving force of the screen can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an overall configuration of a stereoscopic image display system 1 according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an overview of a stereoscopic image display device 100.

FIG. 3 is an enlarged view of a detachable operation switch 22.

FIG. 4 is a diagram showing a configuration including an optical system in the stereoscopic image display device 100.

FIG. 5 is a schematic perspective view of a screen 38 and a rotating disk 39.

FIG. 6 is a conceptual diagram showing an example of how a stereoscopic image is displayed.

FIG. 7 is a conceptual diagram showing another example of how a stereoscopic image is displayed.

FIG. 8 is a block diagram illustrating a functional configuration of the stereoscopic image display system 1.

FIG. 9 is a cross-sectional view showing a configuration for substantially closing the internal space of the enclosure 20a.

FIG. 10 is a cross-sectional view as viewed from a position XX in FIG. 9;

FIG. 11 is a cross-sectional view showing a configuration for substantially sealing the internal space of the enclosure 20r.

FIG. 12 is a sectional view corresponding to a region A surrounded by a virtual line in FIG. 9;

FIG. 13 is a sectional view corresponding to a region A surrounded by a virtual line in FIG. 9;

FIG. 14 shows an enclosure 20a and a housing 20
FIG. 3 is a cross-sectional view showing a configuration for sealing the internal space of FIG.

FIG. 15 is a cross-sectional view showing a configuration for decompressing the internal space of the enclosure 20a.

FIG. 16 is a cross-sectional view showing a configuration for substantially closing the internal space of the enclosure 20a.

FIG. 17 is a diagram showing experimental results regarding the degree of enclosure sealing and motor load.

[Explanation of symbols]

 Reference Signs List 1 stereoscopic image display system 20 housing 20a enclosure 38 screen 39, 39A, 39B, 39C rotating disk 39p packing 79 decompression pump 100 stereoscopic image display device Vs rotating space

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Manami Tsukusako 2-3-1-13 Azuchicho, Chuo-ku, Osaka-shi, Osaka Inside Osaka International Building Minolta Co., Ltd. (72) Inventor Ken Yoshii Azuchi, Chuo-ku, Osaka-shi, Osaka 3-13, Machi-cho, Osaka International Building Minolta Co., Ltd. F-term (reference) 5C061 AA06 AA23 AB12 AB16 5C094 AA22 AA44 AA56 BA16 BA61 CA21 ED01 ED20 5G435 AA16 AA17 BB11 BB17 CC11 DD04 GG01 GG03 GG08 GG46

Claims (9)

[Claims] 1. A stereoscopic image display device for displaying a stereoscopic image by a volume scanning method using an afterimage effect, comprising: (a) a screen rotatable around a central axis parallel to a main surface; Projection optical means for projecting a cross-sectional image of a display object corresponding to the rotation angle of the screen onto the screen; and (c) an opening at one end of the central axis so as to cover the rotation space of the screen. (D) sealing means for substantially sealing the opening, wherein the enclosure is at least partially transparent and the other parts are airtight. A stereoscopic image display device, wherein an airflow generated in the rotation space by rotation of the screen is blocked by an inner wall of the enclosure. 2. The three-dimensional image display device according to claim 1, wherein the screen has a substantially rectangular shape, and the enclosure has a substantially cylindrical shape having a cross section corresponding to a plane size of the screen. Stereoscopic image display device. 3. The three-dimensional image display device according to claim 1, wherein a gap between an outer periphery of the rotating space and an inner wall of the enclosure is 10% or less of a maximum turning radius of the screen. A stereoscopic image display device characterized by the above-mentioned. 4. The stereoscopic image display device according to claim 1, wherein the sealing unit is disposed near the opening of the enclosure, and rotates with the screen. A three-dimensional image display device, comprising: a sealing means for sealing between the rotating disk and a fixed wall surface on the enclosure side. 5. The three-dimensional image display device according to claim 4, wherein the sealing means is a labyrinth seal formed on an outer peripheral portion of the rotating disk and / or on the fixed wall surface. apparatus. 6. The three-dimensional image display device according to claim 4, wherein said sealing means is an elastic seal inserted between an outer peripheral portion of said rotating disk and said fixed wall surface. Stereoscopic image display device. 7. The three-dimensional image display device according to claim 1, wherein the sealing unit includes a housing connected to the enclosure and having a window communicating with the opening. A three-dimensional image display device, which is configured to be airtight in a portion other than the window, and that a rotation driving unit of the screen is housed in the housing. 8. The three-dimensional image display device according to claim 4, wherein the rotation space is reduced in pressure below atmospheric pressure. 9. The stereoscopic image display device according to claim 1, wherein the sealing means includes a rotating disk disposed near the opening of the enclosure and rotating with the screen. A substantial air leak exists between the rotating space and the external space of the device via a gap between the fixed wall on the enclosure side and the rotating disk, and the rotating space is depressurized to an atmospheric pressure or less. A stereoscopic image display device, further comprising: