JP2000278712A - Stereoscopic picture display method, stereoscopic picture display device and computer-readable recording medium storing stereoscopic picture display data - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the efficiency of data transfer in the case of displaying a stereoscopic picture. SOLUTION: A range of updating a crosssectional picture is sequentially being limited with respect to an area on which the crosssectional picture of a display object is displayed. Thus, handled data only data within an updated range of the crosssectional picture so as to reduce a write amount and a read amount of data of the crosssectional picture to/from a memory. As a result, data can efficiently be transferred in matching with a size of the display object and a stereoscopic picture with high definition can be displayed at a high speed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional image display method for displaying a three-dimensional image, and more particularly to a three-dimensional image by displaying a sectional image of a display object on a screen while changing the position and / or orientation of the screen. The present invention relates to a three-dimensional image display method, a three-dimensional image display device, and a computer-readable recording medium for displaying a.

[0002]

2. Description of the Related Art Conventionally, by changing the position and / or orientation of a screen on which an image is projected, the screen is volume-scanned, and a sectional image of a display object is sequentially displayed in synchronization with the scanning position of the screen. A method of displaying a stereoscopic image of a display object is known.

FIG. 28 shows a cross-sectional image 90 of a display object 903 on the screen 901 while repeatedly moving the screen 901 in a direction perpendicular to the main surface (direction indicated by an arrow 902).
4 is a conceptual diagram illustrating a method of displaying a stereoscopic image of a display object 903 by sequentially displaying No. 4.

[0004]

By the way, in the stereoscopic image display by the so-called volume scanning method utilizing the afterimage effect of the human eye, it is necessary to write and read data of many cross-sectional images to and from the memory, which is a high-speed operation. Data transfer is required. However, when actually displaying a stereoscopic image, the periphery of the display target is an area where light is not guided to the screen.

That is, conventionally, the data of the entire cross-sectional image is sequentially read from the memory in synchronization with the scanning of the screen, but the data in the area around the display object is data indicating that light is not guided to the screen. There is data common to each cross-sectional image. Therefore, it can be said that writing and reading to and from the memory are effectively performed as valid data even for a portion where the data content is not changed.
In particular, when the size of the display object is smaller than the size of the screen, the data in unnecessary surrounding areas becomes enormous, and it becomes necessary to transfer much useless data.

Accordingly, the present invention has been made in view of the above problems, and has as its object to improve the efficiency of data transfer when displaying a stereoscopic image.

[0007]

The invention according to claim 1 is a stereoscopic image display method, wherein (a) changing the position and / or posture of a screen on which a sectional image of a display object is projected. Scanning the screen, and (b)
In synchronization with the scanning of the screen, a plurality of 2
While sequentially reading the two-dimensional image data,
Displaying a three-dimensional image of the display object by sequentially projecting a plurality of cross-sectional images on the screen based on the two-dimensional image data, wherein the step (b) comprises: The method includes a step of limiting an update range when a corresponding cross-sectional image is projected by limiting a range of data when writing and / or reading the at least one of the storage units.

According to a second aspect of the present invention, there is provided a stereoscopic image display method, comprising the steps of: (a) scanning the screen by changing the position and / or orientation of the screen on which a sectional image of a display object is projected; (B) a step of writing a two-dimensional image data group corresponding to at least one cross-sectional image of the display object into a storage unit; and (c) the two-dimensional image data from the storage unit in synchronization with scanning of the screen. Reading a group, sequentially projecting the at least one cross-sectional image on the screen based on the two-dimensional image data group, and (d) repeating the steps (b) and (c) to form a plurality of the display objects. Displaying a three-dimensional image of the display object by sequentially projecting the cross-sectional images of the display object, at least before the step (b) is finally executed, (e) for the storage means. The method includes a step of limiting an update range when at least one corresponding cross-sectional image is projected by limiting a range of data at the time of writing and / or reading of the two-dimensional image data group.

According to a third aspect of the present invention, there is provided the stereoscopic image display method according to the second aspect, wherein the step (f) is performed after the step (e).
The method further includes the step of changing the limited update range.

According to a fourth aspect of the present invention, there is provided the stereoscopic image display method according to the second or third aspect, wherein after the step (e), (g) the display object is set according to the limited update range. The method further includes a step of changing the number of cross-sectional images constituting one scene of the object.

According to a fifth aspect of the present invention, there is provided a three-dimensional image display device, wherein a scanning means for scanning the screen by changing a position and / or a posture of the screen on which a cross-sectional image of a display object is projected; A plurality of two-dimensional image data is sequentially read out from the storage unit in synchronization with the scanning of the screen, and a plurality of cross-sectional images are sequentially projected on the screen based on the plurality of two-dimensional image data, thereby obtaining a three-dimensional image of the display target. And, by restricting the range of data at the time of writing and / or reading from / to the storage means for at least one of the plurality of two-dimensional image data, a corresponding cross-sectional image is projected. Means for limiting the update range.

According to a sixth aspect of the present invention, the screen is scanned by changing the position and / or orientation of the screen, and a plurality of cross-sectional images of the display object are sequentially displayed on the screen in synchronization with the scanning of the screen. A computer-readable recording medium that records stereoscopic image display data used when displaying a stereoscopic image of the display target by projecting the stereoscopic image display data, wherein the stereoscopic image display data includes a plurality of cross-sectional images of the display target. And update range data that substantially defines a range in which display should be updated when sequentially projecting the plurality of cross-sectional images.

According to a seventh aspect of the present invention, in the computer readable recording medium according to the sixth aspect, the update range data substantially updates display of each of the plurality of groups of the plurality of cross-sectional images. Specify the range to be performed.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <A. Overall System Configuration> As an embodiment of the stereoscopic image display system according to the present invention,
FIG. 1 shows the overall configuration of the stereoscopic image display system. This stereoscopic image display system 1 includes a stereoscopic image display device 100 that performs stereoscopic display of a display target by a volume scanning method, and a host that supplies two-dimensional image data relating to a cross-sectional image of the display target to the stereoscopic image display device 100. And a computer 3.

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 will be 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 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 computer-readable recording medium 4. is there. As the recording medium 4,
Magneto-optical disk (MO), compact disk (CD-
RW), digital video disk (DVD-RA)
M) and memory cards.

<B. Stereoscopic Image Display> Next, an embodiment of the stereoscopic image display 100 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 includes a housing 20 having a built-in optical system for projecting a cross-sectional image on a screen 38 and a control mechanism for performing various data processing, and an upper portion of the housing 20 provided inside. A windshield 20a that accommodates a rotating screen.

The windshield 20a is formed 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 inner side can be visually recognized from the outside. Further, the windshield 20a seals the internal space, so that the screen 38
The aim is to stabilize the rotation of the motor and reduce the power consumption of the motor that rotates.

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 used as a means for displaying an operation guide screen when performing an operation input and a means for displaying a two-dimensional image for indexing a display object. The digital input / output terminal 24 is a SCSI terminal or an IEEE 1394 terminal.
Terminals. Further, speakers 25 for outputting sound are arranged at four places on the outer peripheral surface of the housing 20.

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 each of 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 on the host computer 3 side. 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 inclination 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 has two major features, namely, firstly, a very high light use efficiency and secondly, a high-speed response. Generally, the DMD 33 makes use of the high light use efficiency. It is used for applications such as video projectors.

In the three-dimensional image display device 100,
By utilizing the high-speed response, which is another great feature of the DMD 33, it is possible to display a moving image of a display target even in a volume scanning method using an afterimage effect.

The DMD 33 generates one image because the response of 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 handle not only the display of a non-rotationally symmetric solid but also the display of a moving image.

Further, one of the features of the DMD 33 is that the light utilization efficiency is high, and a brighter cross-sectional image is displayed on the screen 3.
8 contributes to enhancing the afterimage effect,
A high-quality stereoscopic image can be displayed as compared with a CRT system or the like.

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 changes only the angle of inclination of each micromirror based on the two-dimensional image data provided from the host computer 3 to project only the light components of the illumination light necessary for projecting a cross-sectional image. 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 member 39 for rotating the screen 38 around the rotation axis Z.

The light (cross-sectional image) reflected by the DMD 33 is made parallel 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. Therefore, the projection optical system 50 and the DMD 33 sequentially generate a plurality of cross-sectional images based on the two-dimensional image data, and sequentially project the plurality of cross-sectional images on the screen in synchronization with the rotational scanning of the screen 38. To form a projected image generating means.

In this optical system, the projection mirror 36, the projection lens 513, the projection mirror 37 and the screen 38
Is fixed to a rotating member 39, and a vertical rotating axis Z including the center axis of the screen 38 with the rotation of the rotating member 39.
Rotate at angular velocity Ω around. That is, when rotating the screen 38 for performing volume scanning, the rotating member 3
9, projection mirror 36, projection lens 513
In addition, since the projection mirror 37 also rotates integrally with the screen 38, it is possible to always project the cross-sectional image from the front side regardless of the angle of the screen 38.

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

The cross-sectional image generated by 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 inclined downward (in the case of FIG. 4, a rotating member 39) in front of the screen 38 so as not to disturb the line of sight of the observer when observing the stereoscopic 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 3 of the projection lens 513
The positional order with respect to 7 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 member 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 member 39 rotates rotates in-plane on the screen 38, and the cross-sectional image projected when the rotating member 39 rotates 180 ° is turned upside down with respect to the reference image. It will be a statue.
The image rotation compensating mechanism 34 prevents this phenomenon.

The image rotation compensating mechanism 34 shown in FIG. 4 uses an image rotator constructed 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 member 39 to which the screen 38 is attached, an upright sectional image can always be 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 provided to the DMD 33 so as to be (or an erect image).

Here, the screen 38 and the rotating member 3
FIG. 5 shows an example of a perspective overview view of No. 9. As shown in FIG. 5, the rotating member 39 has a disk shape, and is rotatably driven by a rotating shaft of a motor 74 serving as a rotating drive unit being in contact with a side surface thereof. Note that a motor may be directly connected to the central axis of the rotating member 39, or may be driven via a gear or a belt.

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 continuously projected on the screen 38 regardless of the rotation. Then, when the rotating member 39 is rotated by 180 ° (or 360 °), the same cross-sectional image as the beginning appears again, and one volume scan is completed. The above operation is performed by increasing the rotation speed of the rotating member 39 sufficiently fast so that an after-image effect occurs and by sufficiently increasing the number of cross-sectional images to be projected. You can see the image.

Next, the size (resolution) of the cross-sectional image will be described. FIG. 6 is a diagram showing the size of the cross-sectional image projected on the screen 38. The sectional image has a size of 256 pixels (horizontal direction) × 256 pixels (vertical direction), and is projected symmetrically with respect to the rotation axis of the screen 38. That is, the size becomes 128 pixels on the left and right in the circumferential direction about the rotation axis. Since the projected cross-sectional image rotates together with the screen 38 while maintaining a certain relationship, the screen 3
Regardless of the rotation of 8, the size of the projected cross-sectional image is constant. The size of the cross-sectional image shown in FIG. 6 is merely an example, and an arbitrary size can be set according to the number of micromirrors provided in the DMD 33 to be used.

<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. 7 is a block diagram showing a functional configuration of the stereoscopic image display system 1. In FIG. 7, solid arrows indicate the flow of electric signals, and broken arrows indicate the flow of light. The illumination optical system 40 and the projection optical system 50 shown in FIG. 7 have the above-described contents.

The two-dimensional image data relating to the 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.

In general, since image data has a larger data amount than other types of data, two-dimensional image data input to the interface 66 is often subjected to data compression by the MPEG2 system or the like. In this case, it is necessary to decompress (restore) the compressed two-dimensional image data. Therefore, in the configuration of FIG. 7, a data decompressor 65 for decompressing the compressed two-dimensional image data is provided. When data compression is not applied to the two-dimensional image data input to the interface 66, the data decompressor 6
There is no need to provide 5.

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
It has a controller 62 and memories 63a and 63b. The memories 63a and 63b are configured so that writing or reading is independently controlled, and each functions as a storage unit that 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 according to the rotation angle of the screen 38 detected by the position detector 73, and controls the memories 63a and 63b. Controls a write operation and a read operation.

Here, the configuration of the memory serving as the storage means will be described. Assume that the number of cross-sectional images that can be generated by the DMD 33 when performing volume scanning as described above is 60 sheets. Since the sectional images are intermittently projected in accordance with the rotation angle of the screen 38 to perform stereoscopic display, two-dimensional image data included in the sectional image group is sequentially repeated when 60 sectional image groups are defined as one scene. Data to the DMD 33. Therefore, the storage capacity of the memory for supplying the two-dimensional image data to the DMD 33 requires a memory size capable of storing at least 60 pieces of two-dimensional image data corresponding to one scene.

That is, when the memory size for two-dimensional image data is small, for example, when only two-dimensional image data of less than 60 cross-sectional images can be stored in the memory, the host computer 3 or the recording medium 4
Unless the two-dimensional image data for each cross-sectional image is repeatedly transferred from the device, even a still image cannot be properly displayed in three dimensions. Generally, the speed at which the two-dimensional image data is transferred from the host computer 3 or the recording medium 4 is lower than the speed at which the two-dimensional image data is supplied from the memory to the DMD 33. In such a case, supply of two-dimensional image data in accordance with the rotational position cannot be made in time, and appropriate three-dimensional display cannot be performed.

On the other hand, if the memory size is equal to or more than 60 sheets, all the two-dimensional image data of the sectional image group constituting one scene can be stored in the memory. If the three-dimensional image data is stored, the three-dimensional image can be appropriately displayed by sequentially providing the two-dimensional image data to the DMD 33 according to the rotational position of the screen 38 from this memory.

The above is the same regardless of whether a still image is displayed or a moving image is displayed when performing stereoscopic display.

Next, a memory configuration for displaying a moving image will be described. R, G, B for color display
When an image for each color component is constructed, these R, G, B
One set of images constitutes one cross-sectional image. Therefore, if 60 sheets are made to correspond to each of the R, G, and B color components, the image for each color component has a configuration of 20 sheets. Therefore, considering the size of the cross-sectional image shown in FIG. 6, the memory size required to perform one stereoscopic display is 256 × 256 × 3 × 20 = 3.75 MByte.
(= 30 Mbit).

FIG. 8 is a diagram showing a configuration example of the memory.
FIG. 8A shows an example in which one memory is used for each image of each color component of R, G, and B. Two memories for one cross-sectional image are stored in three memories corresponding to R, G, and B. The image data is stored. Therefore, in the case of FIG. 8A, the memory size of each memory may be small, but at least 60 memory is required to store two-dimensional image data for one scene.
Memory is required. FIG. 8B shows an example in which one memory is used, and FIG. 8C shows an example in which two memories are used.

If the three-dimensional image to be displayed is a still image, two-dimensional image data relating to the cross-sectional image group of all scenes is stored in a single memory as shown in FIG. Output to the DMD 33 for stereoscopic display. However, when a moving image is displayed, the contents of the cross-sectional image to be displayed as one scene change with the rotation of the screen 38, so that the two-dimensional image data in the memory is sequentially updated. It is necessary to go. In other words, when dealing with moving images,
It is necessary to simultaneously read (display) and write (update) two-dimensional image data in parallel. For this reason, the readout of the stored two-dimensional image data and the writing of new two-dimensional image data cannot be performed at the same time with one memory configuration as shown in FIG. Can't respond.

On the other hand, in the case of a configuration having a plurality of memories as shown in FIGS. 8A and 8C, the memory to be read and the memory to be written are sequentially switched. In addition, reading and writing of two-dimensional image data can be performed in parallel in time, and it is possible to support moving image display.

Therefore, when comparing the memory configurations of FIGS. 8A and 8C, in the configuration of FIG. 8A, since there are 60 memories, the configuration of the device becomes complicated, and it becomes a target to be read. While the memory control when sequentially switching between the memory and the memory to be written becomes complicated, in the configuration (c), it is only necessary to alternately switch between the memory to be read and the memory to be written in the two memories. Therefore, the configuration and the memory control are relatively simple. For this reason, in this embodiment, FIG. 7 shows an example in which the memory configuration shown in FIG. 8C is employed as a memory configuration capable of stereoscopically displaying a moving image of a display object.

However, in adopting the memory configuration shown in FIG. 8C, it is necessary to solve the problem of the data transfer speed. In the case of the configuration in FIG. 8C, two-dimensional image data of 256 × 256 × 3 × 20 bytes for one scene is separated and stored in two memories. In this case, the first
256 × 256 × 3 × 10 Byte stored in memory
While the two-dimensional image data is read out and supplied to the DMD 33, the next 256 × 256 × 3 ×
10 bytes of two-dimensional image data must be stored. As described above, the speed at which two-dimensional image data is transferred from the host computer 3 or the recording medium 4 is lower than the speed at which two-dimensional image data is supplied from the memory to the DMD 33. It is conceivable that the writing of the two-dimensional image data for the next half scene to the other memory is not completed while the two-dimensional image data for the half scene is being read from the memory. When such a situation occurs, it becomes impossible to project a cross-sectional image in the latter half when the screen 38 makes one rotation.

In order to solve this problem, in this embodiment, when adopting the memory configuration shown in FIG. 8C, the storage capacity of each memory is required to store at least one scene of two-dimensional image data. Configure to be able to. For example, as shown in FIG. 9, a memory size of 256.times.256.times.3.times.20 Bytes is secured for each memory so that each memory can store one scene of two-dimensional image data. .
By adopting such a configuration, while reading one-scene two-dimensional image data from one memory, writing of the next one-scene two-dimensional image data to the other memory is not completed. In such a case, the same scene as the previous scene can be displayed again by repeating the operation. As a result, since the cross-sectional image is continuously projected on the screen 38 without interruption, the afterimage effect can be maintained.

Therefore, in this embodiment, each of the memories 63a and 63b shown in FIG. 7 corresponds to one scene, that is, a plurality of cross-sectional images necessary for displaying a stereoscopic image of a display object. It is configured to have a memory size capable of storing the dimensional image data group.

The stereoscopic image display device 1 according to the present invention
At 00, the data transfer efficiency at the time of displaying a stereoscopic image is further improved by updating the display only in a specific range of the cross-sectional image. This method will be described later.

Returning to the description of FIG. 7, the system controller 64 controls the image rotation compensating mechanism 34 in the projection lens system 51.
A drive command is given to the screen controller 72 for controlling the rotation operation of the motor and the operation of the motor 74. Also,
The system controller 64 controls the driver 70 that drives the white light source 41, and manages and controls the interface 66 and the data decompressor 65, and controls the DMD controller 6 such as the supply status of two-dimensional image data to the DMD driving unit 60.
2 and so on.

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 receives input information from the detachable operation switch 22. It is configured to be able to 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 unit. 68b and output from the speaker 25. Power supply 6
7 supplies power to each part of the three-dimensional image display device 100 shown in FIG.

FIG. 10 is a diagram in which the main parts of the configuration shown in FIG. 7 are extracted. As described above, in the three-dimensional image display device 100, two memories 63a and 63b are provided to display a moving image related to the display target by changing the three-dimensional image of the display target from time to time, and to one of the memories. The writing operation and the reading operation from the other memory are performed in parallel in time. Specifically, the memory control unit 62a in the DMD controller 62 functions as a control unit for switching between a memory to be read and a memory to be written, and according to the rotation angle of the screen 38 obtained by the position detector 73. The read operation and the write operation of the memories 63a and 63b are alternately switched. The memory control unit 62a and the two memories 63a and 63b are integrated into a buffer when a two-dimensional image data group in which the entirety of one scene of the display target is collectively expressed by a plurality of cross-sectional images is input. It functions as a buffer means for executing.

The two-dimensional image data supplied from the data decompressor 65 is supplied to both of the memories 63a and 63b, but only the one of the two memories to which a write command is given by the memory control unit 62a is designated. The two-dimensional image data is written (or updated) sequentially from the address. On the other hand, the memory to which the read command is given from the memory control unit 62a sequentially outputs a plurality of stored two-dimensional image data based on the command from the memory control unit 62a, and gives the DMD 33 to the DMD 33.

The memory control unit 62a specifies a read address for one of the memories 63a (or 63b) in order to cause the DMD 33 to generate a cross-sectional image based on the rotation angle obtained from the position detector 73. By controlling the reading operation of the two-dimensional image data, the display of the cross-sectional image is controlled. When the projection of the cross-sectional image group for one scene is completed, the other memory 6
It is determined whether or not writing of the next one-dimensional image data for one scene to 3b (or 63a) has been completed.
If the processing has been completed, the memory of the read target and the memory of the write target are switched. If the processing has not been completed, the same scene is repeatedly projected again from one of the memories 63a (or 63b) to be read. The two-dimensional image data is sequentially read.

The memory control unit 62a for performing such control
FIG. 11 is a functional block diagram showing the details of FIG. That is, the counter 81 counts a pulse signal corresponding to the rotation angle obtained from the position detector 73 and sends the result to the read address generation unit 82 and the switching unit 84. The read address generator 82 specifies a cross-sectional image suitable for the current position of the screen 38 based on the count result, and generates a read address for reading the two-dimensional image data. On the other hand, the write address generator 83 generates a write address of the two-dimensional image data supplied based on the supply state of the two-dimensional image data from the data decompressor 65 transmitted from the system controller 64. The addresses generated by the read address generator 82 and the write address generator 83 are guided to the switching unit 84, respectively. The switching unit 84 is a counter 81
When it is determined that the projection of the cross-sectional image group for one scene has been completed based on the rotation angle from, it is checked whether the writing of the two-dimensional image data for the next one scene to the other memory has been completed. If the processing has been completed, the memory for the read target and the memory to be written are switched to switch the destination of the read address and the write address, and if not completed, the switching operation is not performed.

By performing such a configuration and control, it is possible to update the cross-sectional image projected on the screen 38 with the rotation of the screen 38, and to display the moving image of the display object in the stereoscopic display by volume scanning. An image can be displayed. Further, when the reading of the two-dimensional image data relating to the cross-sectional image group for one scene from the memory to be read is completed, the input from the host computer 3 or the expansion processing in the data expander 65 is still completed. No, 2 for the other memory
Even when the writing (updating) of the three-dimensional image data is not completed, it is possible to prevent the cross-sectional image projected on the screen 38 from being interrupted, and to always maintain an appropriate three-dimensional display. Become.

Next, generation of two-dimensional image data relating to a cross-sectional image will be described. FIG. 12 is a block diagram showing a functional configuration of the host computer 3 of FIG. The CPU 3a of the host computer 3 functions as a three-dimensional data storage unit 91, a three-dimensional display condition input unit 92, and a cross-sectional image calculation unit 93. Then, from the three-dimensional image data of the display target, two-dimensional image data is derived for each cross-sectional image corresponding to the rotation angle of the screen 38, and the data is supplied to the three-dimensional image display device 100 side.

The three-dimensional data storage section 91 stores three-dimensional image data of a display object. The three-dimensional image data stored here is data on a moving image of a display target.
For example, by storing each form of the display object from the initial state to the final state as one piece of three-dimensional image data in the three-dimensional data storage unit 91, a three-dimensional image related to a moving image of the display object is stored. Data can be stored.

A three-dimensional display condition input unit 92 is provided for setting display conditions and the like on what size and posture of the stored display object is to be displayed. Based on the two-dimensional image data and the display conditions provided from the three-dimensional display condition input unit 92, the two-dimensional image data of the cross-sectional image obtained by cutting the display target at predetermined angle intervals is derived by the cross-sectional image calculation unit 93.

FIG. 13 is a diagram showing a process of converting three-dimensional image data into two-dimensional image data performed in the cross-sectional image calculation unit 93. First, a rotation axis serving as a central axis when performing rotation display is set for three-dimensional image data of a display target as shown in FIG. This state is shown in FIG.
(B). Then, the number of divisions of the three-dimensional image data per rotation is set, and the display object is cut into radial planes at substantially equal angles according to the number of divisions as shown in FIG. By expressing, as image data, a cross-sectional image of the display object guided by this cutting, FIG.
Two-dimensional image data relating to a cross-sectional image of the display object cut at predetermined angles as shown in (d) is generated.

All the two-dimensional image data of the cross-sectional image group necessary for displaying the three-dimensional image of the display object during one rotation as shown in FIG. Become. By performing three-dimensional display based on the two-dimensional image data for one scene, a three-dimensional image can be projected when the display object is in one state. Then, in the case of a moving image, the section image calculation unit 93
In each of the modes from the initial state to the final state of the display object, two-dimensional image data in which one scene is one unit is sequentially derived, and the data is sequentially extracted from the three-dimensional image display device 100. It is supplied to the side.

The derived two-dimensional image data is subjected to data compression by a method such as MPEG2 as required.

<D. Correction of Projected Image> Next, the necessity of correcting the projected image will be described. There are two points where the projection image needs to be corrected. First, in projecting the cross-sectional image on the screen 38, the distortion of the cross-sectional image due to the difference in the optical path length between the upper side and the lower side of the screen 38 is corrected. Second, screen 38 is
When one volume scan is completed at the time of rotating by 80 °, cross-sectional images to be projected when the projection surface of the screen 38 is on the front side and on the back side with respect to the observer. Is reversed right and left.

First, the correction of the first projected image will be described. In the three-dimensional image display device 100, the projection mirror 37 is disposed at a position shifted obliquely downward from the front of the screen 38 as shown in FIG. . Therefore, the optical path length differs between the upper and lower portions of the screen 38, and the screen 3
8, the cross-sectional image is relatively enlarged and projected on the upper side compared to the lower side. In this state, the stereoscopic image is distorted, and it is necessary to correct the difference in the scale of the projected image.

As an example of a method for correcting a projected image, a DMD
There is a method in which the cross-sectional image generated in 33 is corrected in advance to give a difference in scale between the upper side and the lower side of the image. Specifically, when the cross-sectional image P3 to be actually projected has a rectangular ring shape as shown in FIG. 14A, the cross-sectional image P4 generated by the DMD 33 is lower than that shown in FIG. D to form a trapezoidal ring-shaped image with the scale reduced at the top
The two-dimensional image data given to the MD 33 is corrected in advance. The correction means for performing this correction includes a host computer 3
When generating two-dimensional image data on the side, the host computer 3 reduces the upper scale as compared to the lower scale.
The data decompressor 65 itself may be used as a correction means, and the data decompressor 65 may be used as a correction means so as to perform correction when decompression is performed in the data decompressor 65 shown in FIG. Correction means for performing such correction may be provided alone. The scale reduction rate is
Since it is preferable to set so as to cancel the enlargement ratio at the time of projection on the screen 38, it is preferable that the correction means is provided on the three-dimensional image display device 100 side.

As another example of a method of correcting a projected image, for example, a lens system having a refraction characteristic that is asymmetric with respect to the optical axis (a lens having a small magnification on the upper side and a large magnification on the lower side) System) in the projection optical system. In this case, the lens system can be disposed between the projection mirror 36 and the projection mirror 37, between the projection mirror 37 and the screen 38, and between the DMD 33 and the image rotation compensating mechanism.

In addition, a plurality of projection mirrors 36 and 37 are used to reduce the image with respect to the light projected upward and enlarge the image with respect to the light projected downward. May be adopted. When the projection mirror 36 and the projection mirror 37 are both curved mirrors, and finally projected onto the screen 38, the image is reduced for light projected upward,
The image may be enlarged for light projected downward.

Next, the correction of the second projected image will be described. All the two-dimensional image data of the cross-sectional image group projected when the screen 38 is rotated by 360 ° are stored in the memories 63a, 63a.
3b, and when the 360 ° rotation of the screen 38 is one volume scan, an appropriate cross-sectional image is projected to the observer even when the projection surface of the screen 38 is on the front side or the back side. It can be carried out.

However, when the screen 38 is 180 °
The two-dimensional image data of the cross-sectional image group to be projected when rotating is stored in the memories 63a and 63b.
When the 0 ° rotation is one volume scan, the screen 38 is used.
When projecting a non-rotationally symmetric three-dimensional image on the top, it is necessary to invert the cross-sectional image when the projection plane is on the front side and when it is on the back side. This is because, for example, when the left-right inversion is not performed in order to display a three-dimensional image of a coffee cup as a display object, the display object is three-dimensionally displayed even though the coffee cup of the display object has only one handle portion. This is because two handles are displayed on the image in a symmetrical positional relationship with respect to the rotation axis.

As an example of the method of performing the left-right reversal, there is a method of switching the read addresses of the memories 63 a and 63 b in supplying two-dimensional image data from the memories 63 a and 63 b to the DMD 33 according to the rotation angle of the screen 38. is there. In this method, in order to invert the cross-sectional image every time the screen 38 rotates by 180 °,
It is only necessary to switch the data reading order in the horizontal direction of the cross-sectional image, and it is not necessary to change the vertical direction of the cross-sectional image.

For example, when the size of the cross-sectional image is 256 pixels (horizontal direction) × 256 pixels (vertical direction) as shown in FIG. 6, the horizontal scale at the time of reading the two-dimensional image data from each of the memories 63a and 63b is determined. The address is 8 bits, and the 0th to 255th pixels in the horizontal direction can be designated. Then, the memory controller 62a shown in FIG. 10 sends the DMD 33 from the memories 63a and 63b in accordance with the rotation angle of the screen 38 obtained from the position detector 73.
Of the two-dimensional image data to be given in the horizontal direction.

FIG. 15 is a diagram showing the reading order from the memories 63a and 63b according to the rotation angle θ of the screen 38. As shown in FIG. 15, the memories 63a and 63b
Stores n pieces of two-dimensional image data as a group of cross-sectional images projected when the screen 38 is rotated by 180 °. When the rotation angle θ of the screen 38 is in the range of 0 ° ≦ θ <180 ° as shown in FIG. 15A, n pieces of two-dimensional image data are sequentially sequentially shifted rightward in the horizontal direction. Image data D0, D1, D2 for each pixel,
.., D255 are read and supplied to the DMD 33.
On the other hand, as shown in FIG.
Is within the range of 180 ° ≦ θ <360 °, the n pieces of two-dimensional image data are sequentially converted to image data D255, D of one pixel in the horizontal left direction.
, D253,..., D0 are read out and DMD33 is read.
Supplied to

That is, when the rotation angle θ of the screen 38 is 0
When the angle is in the range of ° ≦ θ <180 °, each image data of the two-dimensional image data is sequentially read in a horizontal right direction orthogonal to the rotation axis Z as a first read mode, The rotation angle θ of the screen 38 is 18
If the angle is within the range of 0 ° ≦ θ <360 °, the image data of the two-dimensional image data is sequentially read in the horizontal left direction orthogonal to the rotation axis Z as the second reading mode.

FIG. 16 shows an example of a control mechanism for switching the reading order. FIG. 16 shows a detailed configuration of the read address generator 82 shown in FIG. As shown in FIG.
Are the first address generator 82a and the second address generator 82
b and an address selection unit 82c. The first address generator 82a determines that the rotation angle θ of the screen 38 is 0 ° ≦ θ <
The second address generator 82b generates a read address when the rotation angle θ of the screen 38 is in a range of 180 ° ≦ θ <360 ° (that is, the first address). Generator 82a
The read address in which the horizontal read order generated in (1) is set in the reverse order is generated. The first address generator 82a and the second address generator 82b both specify a cross-sectional image suitable for the current position of the screen 38 based on the count result obtained from the counter 81 and read out the two-dimensional image data. Address is always generated.

FIG. 17 shows these address generators 82a, 82a,
FIG. 7 is a diagram showing an example of an 8-bit horizontal address signal generated at 82b. In FIG. 17, (a) shows an address signal generated by the first address generator 82a, and (b) shows an address signal generated by the second address generator 82b. Note that FIGS. 17A and 17B
, A0 to A7 indicate signals in bit units.

As shown in FIG. 17, when the rotation angle of the screen 38 is in the range of 0 ° ≦ θ <180 °,
When 0 ° ≦ θ <360 °, the bit signals A0 to A7 have a level-inverted relationship. As a result, when it is within the range of 0 ° ≦ θ <180 °, FIG.
Data for each pixel is read out in the order shown in FIG. 15A, and when it is within the range of 180 ° ≦ θ <360 °, data for each pixel is read out in the order shown in FIG. Will be issued. As shown in FIG. 17, the read address is set for the second and subsequent lines of the two-dimensional image data in the same read procedure (direction) as the first line.

Thus, the first address generator 82a
The read addresses generated by both the address generator 82b and the second address generator 82b are guided to the address selector 82c. In the address selecting section 82c, the rotation angle θ obtained from the counter 81 is in the range of 0 ° ≦ θ <180 ° and 180 ° ≦ θ <36.
It is checked whether the angle falls within the range of 0 °, and 0 ° ≦
When θ <180 °, the address signal (see FIG. 17A) generated by the first address generation unit 82a is supplied to the above-described switching unit 84, and 180 ° ≦
If θ <360 °, the address signal (see FIG. 17B) generated by the second address generation unit 82b is supplied to the switching unit 84 described above.

By adopting the above configuration,
When reading two-dimensional image data from the memory 63a or 63b, the reading order corresponding to the horizontal direction of the cross-sectional image can be inverted (switched) according to the rotation angle of the screen 38. As a result, the two-dimensional image data given to the DMD 33 becomes the left and right inverted data every time the screen 38 is rotated by 180 °.
The cross-sectional image projected on 8 is also flipped horizontally every 180 ° rotation. As a result, when the 180 ° rotation of the screen 38 is performed as one volume scan, it is possible to realize left-right reversal of the cross-sectional image, and it is possible to satisfactorily correct the projected image.

Note that the three-dimensional image display device 1 according to the present invention.
In 00, the data transfer efficiency at the time of displaying a stereoscopic image is improved by updating the display only in a specific range of the cross-sectional image. Therefore, the address signal shown in FIG. The storage area shown in FIG. 15 is made smaller. The limitation of the updating range of the cross-sectional image will be described below.

<E. Limiting the update range of the cross-sectional image>
In the stereoscopic image display device 100, the memories 63a and 63 are updated by updating only a predetermined range of the cross-sectional image (that is, limiting a range in which the content of the cross-sectional image is changed).
A method for reducing the amount of data written to and data read from b will be described.

FIG. 18 (a) is a conceptual diagram showing a state of a standing human being displayed from the front, and FIG. 18 (b) is a conceptual diagram showing it from above. The maximum cross-sectional image size that can be displayed on the stereoscopic image display device 100 is 256 pixels × 25.
Assuming that there are six pixels, in the example shown in FIG. 18, the size of the displayable area of the stereoscopic image is larger than the area where the display is actually performed, that is, the area where the light is guided from the DMD 33 to the screen 38. Become.

However, when displaying a stereoscopic image by the volume scanning method, light is not guided to the screen 38 except for the region where the display object is displayed. Are the same.

Therefore, in the three-dimensional image display device 100, the operation of writing and reading the data in the areas indicated by the parallel oblique lines in FIGS. 19A and 19B to and from the memories 63a and 63b is omitted. I have. In the case of the example shown in FIG. 19, the actual size of one slice image is 256
Pixels × 128 pixels, and only data in this range is treated as two-dimensional image data. With such a technique, the stereoscopic image display device 100 achieves a reduction in the amount of data and an efficient data transfer.

FIG. 20 is a diagram showing a region where a stereoscopic image is substantially displayed in the example shown in FIG.
(A) is a conceptual view from the front, and (b) is a conceptual view from above. As shown in FIG. 20, by sequentially projecting a cross-sectional image of 256 pixels × 128 pixels as shown in FIG. 20, that is, by limiting the update range of the cross-sectional image to 256 pixels × 128 pixels which is １ ／ of the original. A display completely equivalent to the stereoscopic image display is realized. As a result, the memory 63a,
63b, the amount of data writing and reading is 1 /
2 and efficient data transfer is realized.

Next, the state of the two-dimensional image data actually written in the memories 63a and 63b will be described with reference to FIG. FIG. 21A shows a case where the displayable area is 256 pixels × 256 pixels illustrated in FIG. 18 and two-dimensional image data corresponding to each cross-sectional image of this size is stored in the memory 63a (or 63b, hereinafter simply referred to as “memory”). It is a figure which shows a mode that 60 pieces were written in "."). In contrast, FIG.
FIG. 20B shows that the update range of the cross-sectional image is 256 as illustrated in FIG.
FIG. 9 is a diagram illustrating a state in which 60 pieces of two-dimensional image data corresponding to each cross-sectional image are written in the memory in the case of pixels × 128 pixels. As shown in FIG. 21B, by limiting the range in which the cross-sectional image is actually updated in the displayable area of the stereoscopic image display device 100 in advance, the amount of data to be written to the memory and the data to be read from the memory The amount can be reduced.

By limiting the updating range of the cross-sectional image, the amount of data to be written to and read from the memory can be reduced as described above, and the display of the stereoscopic image can be followed even when the screen 38 is rotated at a higher speed. Can be done. As a result, a flicker-free and smooth moving image can be displayed.

On the other hand, by reducing the amount of two-dimensional image data corresponding to one cross-sectional image, the number of two-dimensional image data that can be stored in the memory can be increased. FIG. 21C is a diagram showing a state in which data of 256 pixels × 128 pixels has been written to 120 memories. As shown in FIG. 21C, when one scene is originally composed of 60 slice images, the number of slice images constituting one scene is reduced by halving the two-dimensional image data of each slice image. It can be doubled to 120 sheets. As a result, a higher definition stereoscopic image can be displayed in displaying a still image and a moving image.

When the data shown in FIGS. 21 (b) and 21 (c) are stored in the memory, the read address generation unit is provided so that the limited storage area can be properly accessed at the time of writing and reading. 82 and the address signal from the write address generator 83 (FIG. 11) are appropriately changed. Also, the read data is DMD 33
The address signal inside the DMD 33 is also appropriately corrected so that the address signal is stored at an appropriate position. Thereby, the two-dimensional image data stored in the memory is transferred to a limited range on the DMD 33, and only the contents of the cross-sectional image within the limited update range are updated and projected on the screen 38.

<F. Outline of processing procedure in stereoscopic image display device> Next, an outline of a processing procedure when a stereoscopic image is actually displayed in the stereoscopic image display apparatus 100 will be described. FIG. 22 to FIG. 24 are flowcharts showing this processing procedure. FIG. 23 is a flowchart relating to display processing when an image for performing stereoscopic display is a still image, and FIG. 9 is a flowchart related to a display process when is a moving image.

In the flowchart of FIG. 22, first, initial settings are made (step S1). The contents of the initialization include stabilization of the power supply and initialization of parameters relating to various processing conditions. In addition, the rotational scanning of the screen 38 is also started.

Step S2 and subsequent steps are steps for displaying a stereoscopic image. In step S2, the observer (operator)
Input from the operation switch 22 for selecting a data file. For example, when two-dimensional image data is stored in the recording medium 4 in the configuration of FIG. 7, a file name or the like relating to the two-dimensional image data is displayed on the liquid crystal display 21, and the observer can use A desired data file is selected while visually confirming the display contents of. When two-dimensional image data is stored in the host computer 3, data communication is performed between the three-dimensional image display device 100 and the host computer 3 under an instruction of the system controller 64, and the host computer 3 Is displayed on the liquid crystal display 21. As a result, the observer selects a desired data file while viewing the display contents of the liquid crystal display 21.

When the data file is selected, the process proceeds to step S3, where the header file of the data file selected in step S2 is input. That is, the system controller 64 acquires the header file from the recording medium 4 or the host computer 3.
The header file contains information on the size of the cross-sectional image, that is, how many pixels each is formed in the horizontal and vertical directions of the cross-sectional image, the number of cross-sectional images forming a scene, and one volume scan. ° rotation or 36
Various information necessary for three-dimensional display such as information on whether to rotate by 0 °, the number of scenes in the case of a moving image, and a data format indicating whether the two-dimensional image data is in a still image format or a moving image format are included. include.

At step S4, the system controller 64 identifies the data format from the header file and identifies whether the stereoscopic image to be displayed is a still image or a moving image. Then, the above-mentioned various information is transmitted to each section, and a preparation stage for the stereoscopic display is started.

FIG. 25 shows a host computer 3 or a computer-readable recording medium (magnetic disk,
FIG. 3 is a diagram illustrating a structure of data (hereinafter, referred to as “stereoscopic image display data”) 801 transferred from a magneto-optical disk, an optical disk, or the like 4 to the stereoscopic image display device 100. The stereoscopic image display data 801 is roughly divided into a header 811 that is data of a projection condition and the like, and a two-dimensional image data 812 that is data of a cross-sectional image to be projected.
Is the system controller 6
4 acquired.

As described above, the header 811 includes data indicating the size of a substantial cross-sectional image, that is, data that defines a range in which the cross-sectional images are substantially sequentially updated (hereinafter referred to as “update range data”). ). The update range data 813 is sent from the system controller 64 to the read address generator 82 and the write address generator 83 in the DMD controller 62, so that the appropriate read address and write address Is generated, and a cross-sectional image limited to the displayable area is projected at an appropriate position on the screen 38. That is, the system controller 64, the read address generator 82, and the write address generator 8
3 serves as a means for limiting the update range. Note that the content of the update range data 813 is generated based on the size and data amount of the display target when a cross-sectional image for displaying a stereoscopic image is generated from the three-dimensional image data.

The header 811 also includes data of the number of cross-sectional images constituting one scene (hereinafter referred to as “update speed data” since it is data corresponding to the speed of updating the cross-sectional images) 814, This update speed data 814
Is appropriately generated by the host computer 3 or the like in accordance with the update range data 813. That is, the update range data 8
When the update range specified by 13 is small, the value of the update speed data 814 is set large, and when the update range is large, the update speed data 814 is set small.

After step S4, the apparatus is in a standby state for input from the operation switch 22 (step S5), and a display start instruction from the observer (ie, operation of the start button 222).
If there is, the process proceeds to step S6, and if there is no display start instruction, the process returns to step S2. When the observer inputs a display start instruction for a still image, the observer also sets the display time of the still image.

In step S6, it is determined whether the data format identified in step S4 is a still image or a moving image. If it is a still image, the process proceeds to step S7, and if it is a moving image, the process proceeds to step S8. .

When the operation proceeds to the still image display mode (step S7) as shown in FIG. 23, first, two-dimensional image data is input from the recording medium 4 or the host computer 3 under the control of the system controller 64. Start. As a result, the two-dimensional image data of the still image is sequentially supplied to the data decompressor 65 via the interface 66 for each cross-sectional image. Then, the two-dimensional image data expanded while performing the expansion processing in the data expander 65 is written to one of the two memories 63a and 63b (or 63b) (step S71). At this time, the memory control unit 62a in the DMD controller 62 designates one memory 63a (or 63b), and sequentially designates write addresses for that memory. When the writing of the two-dimensional image data for all the cross-sectional images for displaying the still image is completed, the process proceeds to step S72.

In step S72, one memory 63a (or 63b) in which the two-dimensional image data has been written is stored.
Are sequentially read, and the read two-dimensional image data is provided to the DMD 33. As a result, a sectional image corresponding to the two-dimensional image data given to the DMD 33 is projected on the rotating screen 38.

Then, all of the two-dimensional image data stored in the memory 63a (or 63b) is
When the time is supplied to 3, the process proceeds to step S73 to determine whether or not the display time has exceeded the set time. If the display time has not reached the set time, the process returns to step S72 to display the same cross-sectional image again. On the other hand, if the set time has passed, the processing relating to the display of the still image ends.

It is to be noted that in the case where the processing of step S72 is repeatedly performed, the 180 ° rotation of the screen 38 is changed by one.
If the volume scanning is performed twice, this step S72 is performed.
Each time is performed, a read address for inverting the cross section image described above is generated. By doing so, it is possible to satisfactorily correct the projected image in the still image display.

Next, a description will be given of a case where the process has proceeded to the moving image display mode (step S8) as shown in FIG. Even when the operation proceeds to the moving image display mode (step S8), first, input of two-dimensional image data from the recording medium 4 or the host computer 3 is started under the control of the system controller 64. As a result, the two-dimensional image data of the moving image is sequentially supplied to the data decompressor 65 via the interface 66 for each cross-sectional image. However, in the case of a moving image, since it is the same as a group of a plurality of two-dimensional image data for one still image,
Even if the input of the dimensional image data is started, the data input is not completed immediately. Therefore, stereoscopic display of a moving image is performed while data is input from the recording medium 4 or the host computer 3.

In the data decompressor 65, the interface 66
The expansion processing is sequentially performed on the two-dimensional image data input through the CPU, and the resulting two-dimensional image data is sequentially output to the memories 63a and 63b.

In step S81, the memory control unit 62a of the DMD controller 62 sets one of the memories 63a as a write target, and specifies a write address for the memory 63a. As a result, the two-dimensional image data for the first scene is sequentially written to the memory 63a. When the writing of the two-dimensional image data for one scene is completed, the process proceeds to step S82.

In step S82, the memory control unit 62a
Converts the two-dimensional image data written in the memory 63a to the DM
In order to provide the data to D33, the memory 63a is set as a read target and the other memory 63b is set as a write target. As a result, the two-dimensional image data for the first scene is supplied to the DMD 33 and the rotating screen 3 is used.
8 and obtained from the data decompressor 65
The two-dimensional image data for the scene is sequentially written to the memory 63b. In this step S82, when the reading of the two-dimensional image data stored in the memory 63a is completely completed, the next one to the memory 63b is read.
If the writing operation for the scene has not been completed, reading from the memory 63a is repeated again, and the same cross-sectional image as the previous time is projected on the screen 38. On the other hand, if the reading of the next one scene to the memory 63b has been completed when the reading of the two-dimensional image data stored in the memory 63a has been completed, the process proceeds to step S83.

Then, in a step S83, it is determined whether or not the two-dimensional image data supplied from the data decompressor 65 to the memories 63a and 63b is completed. That is, it is determined whether two-dimensional image data for all scenes for displaying a moving image has been stored in the memories 63a and 63b. Then, from the data decompressor 65 to the memory 6
If the two-dimensional image data supplied to the 3a, 63b side continues, the next scene exists, so that “NO” is determined in the step S83, and the step S83 is performed.
Proceed to 84. On the other hand, when the two-dimensional image data supplied to the memories 63a and 63b does not exist, the two-dimensional image data written in the memory 63b in step S82 is the last scene. To display step S86.

In the step S84, the memory control unit 62a
Converts the two-dimensional image data written in the memory 63b into the DM
In order to provide the data to D33, the memory 63b is set as a read target and the other memory 63a is set as a write target (update target). As a result, two-dimensional image data for one scene following one scene displayed in step S82 is supplied to the DMD 33 and projected on the rotating screen 38, and the next one scene obtained from the data decompressor 65 is obtained. Minute two-dimensional image data is sequentially written to the memory 63a. Note that also in this step S84, when reading of the two-dimensional image data stored in the memory 63b has been completed,
If the writing operation for the next one scene for a has not been completed, the reading from the memory 63b is repeated again, and the same cross-sectional image as the previous time is projected on the screen 38. On the other hand, if the reading of the next one scene to the memory 63a has been completed when the reading of the two-dimensional image data stored in the memory 63b has been completed, the process proceeds to step S85.

Then, in step S85, step S8
A determination similar to 3 is made. Therefore, if the two-dimensional image data supplied from the data decompressor 65 to the memories 63a and 63b continues further, the next scene exists, so "NO" in step S85.
Is determined, the process proceeds to step S82, and the memories 63a, 63
If there is no two-dimensional image data supplied to the 3b side, the two-dimensional image data written in the memory 63a in step S85 is the last scene, so the process proceeds to step S86 to display the last scene. .

In steps S82 and S84,
It is clear from the contents already described that writing of two-dimensional image data to one memory and reading of two-dimensional image data from the other memory are performed simultaneously and in parallel.

In step S86, in order to project the last one scene on the screen 38, two-dimensional image data is read from one of the memories 63a or 63b, and is read by the DM.
The operation given to D33 is performed.

The moving image display is performed in this manner. When reading out the two-dimensional image data from the memory 63a or 63b in steps S82, S84 and S86, the cross-sectional image projected on the screen 38 is horizontally inverted. When it is necessary to change the read address in the horizontal direction as described above, the read address is switched.

By performing the processing procedure as described above,
It is possible to appropriately and stereoscopically display not only a still image but also a moving image within a limited update range.

FIG. 26 is a flowchart showing another example of the operation in the moving image display mode in step S8 in FIG. In the operation of the moving image display mode shown in FIG.
According to the contents of the header file input in Step S3 of Step 2, the update range and update speed of the cross-sectional image are set before displaying the stereoscopic image.

On the other hand, in the operation shown in FIG. 26, the updating range and the updating speed of the cross-sectional image are not set in step S4, but need to be performed each time a cross-sectional image of one scene is displayed. Is set in advance. That is,
First, an update range and an update speed are set before the two-dimensional image data is written to the memory 63a (steps S81a and S81), and thereafter, the update range and the update range are set before the two-dimensional image data is written to the memories 63a and 63b. The update speed is changed as needed (step S82).
a, S82, S84a, S84).

For example, when the display object displayed in the first several scenes is large and the display object displayed in the subsequent several scenes is small, the update range of the cross-sectional image of the first several scenes is 256 pixels × 256 pixels. (That is, the update range is not limited and the cross-sectional image is updated over the entire displayable area), and the number of cross-sectional images (update speed) constituting one scene is set to 60. After that, several scenes are displayed without changing these settings, and when it is time to display a small display object, the updating range of the cross-sectional image is changed to 256 pixels × 128 pixels to constitute one scene. The number of slice images to be changed is changed to 120.
Such an operation realizes efficient display according to the size of the display object.

The update range and update speed are changed as needed (steps S82a and S84a), and the initial setting of the update range and update speed (step S81a) is performed when the header file is read (step S81a). It may be performed in step S3). If the initial setting is not performed, the displayable area may be predetermined as the update range by default. That is, at least once at any stage (ie, before the last write of data to the memory) before data is written to the memory,
If the update range is limited, the data transfer efficiency can be improved.

FIG. 27 is a diagram showing the structure of stereoscopic image display data 802 when the operation shown in FIG. 26 is performed. The stereoscopic image display data 802 has a header 821 and two-dimensional image data 822 as in the case of the stereoscopic image display data 801 shown in FIG. 25, and the header 821 includes update range data 823 and update speed data 824 of the cross-sectional image. included. The two-dimensional image data 822 is divided into a plurality of groups, and an auxiliary header 821a is arranged before each group.

The auxiliary header 821a is data defining conditions unique to the subsequent two-dimensional image data 822, and includes update range data 823 and update speed data 824.
Is included. That is, in the three-dimensional image display device 100,
Each time the auxiliary header 821a is input, the update range of the cross-sectional image and the number of cross-sectional images forming one scene are changed (steps S82a and S84a), and the subsequent two-dimensional image data 822 is changed according to the changed setting. Writing to and reading from the memory and projection of the cross-sectional image are performed.

As described above, in the three-dimensional image display apparatus 100, the storage capacity of the writing and reading range of the two-dimensional image data in the memory is changed to the data amount corresponding to the corresponding cross-sectional image (256 pixels in the above example). (The data amount of 256 pixels), efficient data transfer is realized, and high-speed display of a stereoscopic image is realized. In addition, a smooth display is realized by improving the update speed.

<G. Modifications> While the embodiment of the stereoscopic image display device and the stereoscopic image display system according to the present invention has been described in detail, the present invention is not limited to the above-described embodiments.

For example, in the above embodiment, by limiting the update range of the cross-sectional image, the storage capacity of the range in which the two-dimensional image data corresponding to one cross-sectional image is written to and read from the memory is limited. However, only one of the writing range and the reading range for the memory may be limited.

The form of the two-dimensional image data stored in the memory is 256 pixels × 25 pixels as shown in FIG.
It is data of 6 pixels, and writing of new data is 25
The data of 6 pixels × 128 pixels may be read at a corresponding location on the memory, and the reading may be performed in units of 256 pixels × 256 pixels. When the writing of data to the memory is the rate-determining step in displaying a stereoscopic image, the data can be quickly written to the memory, and the efficiency of image display can be improved.

On the other hand, the form of the two-dimensional image data stored in the memory is 256 pixels × 2 pixels as shown in FIG.
It is 56 pixel data, and writing of new data is also 2
Reading is performed in units of 56 pixels × 256 pixels, but reading may be performed only in a necessary range in units of 256 pixels × 128 pixels. When the reading of data to the memory is the rate-determining step in displaying a stereoscopic image, the data can be quickly read from the memory, and the efficiency of image display can be improved.

As described above, the efficiency of displaying a stereoscopic image can be improved even when only one of the data writing range and the data reading range for the memory is limited. That is, if the update range of the cross-sectional image when displaying the stereoscopic image is substantially limited, the display efficiency can be improved.

In the above description, the case where the number of memories as the storage means is two is exemplified. However, since there is no technical limit to be limited to two, two or more memories may be used. In this case, when switching between one memory to be read and one memory to be written, a configuration may be adopted in which switching is performed cyclically among a plurality of memories. As described above, when only a still image is displayed, only one memory may be used. If there is no need to switch scenes at high speed, the display of a moving image may be performed by one memory depending on the specification. It is possible.

The number of cross-sectional images corresponding to the two-dimensional image data group that can be stored in the memory is not limited to one scene. Is sufficiently fast, the storage capacity of one cross-sectional image may be used. That is, the number of two-dimensional image data that can be stored in the memory may be at least one. Note that the storage capacity may be one or less as long as writing and reading to and from the memory can be performed at very high speed.

In summary, the data transfer efficiency can be improved by restricting the range of data when writing and / or reading data from or to at least one of the two-dimensional image data. It can be said that.

In the above embodiment, 256 pixels × 256 pixels are set as 256 pixels × 1
Although a case where the number of pixels is limited to 28 pixels has been described as an example, the range to be limited may be arbitrary, for example, 100 pixels × 100 pixels.
Pixels may be used, and the update range of the cross-sectional image is not limited to a rectangle.

The update range data 823 and the update speed data 824 in the stereoscopic image display data 802 shown in FIG. 27 may all be included in the header 821, and such a header 821 is used as a header file. It may be prepared separately.

In the above embodiment, the header file is read (step S3) or before a stereoscopic image of one scene is displayed (steps S81a and S82).
(a, S84a) The update range of the cross-sectional image and the number of cross-sectional images constituting one scene are set or changed, but only the update range of the cross-sectional image may be set or changed.

Further, the change of the updating range and the updating speed of the sectional images is not limited to being performed in units of one scene, but may be performed for each arbitrary number of sectional images. For example, when displaying a still image or a moving image, the update range may be changed for each display of the cross-sectional images, or the update range may be changed for every 1/2 scene.

Further, the update speed does not change every time the update range of the slice image is changed, and the rotation speed of the screen 38 may be changed. As a result, the flicker of the still image display is suppressed, and the smooth display is realized in the moving image display.

As an example of image generating means for generating a cross-sectional image to be projected on the screen 38 based on two-dimensional image data supplied from a memory to be read, D
Although the MD 33 is illustrated, an element other than the DMD 33 may be used.

In the above description, a configuration example in which a three-dimensional image of a display object is displayed by projecting a cross-sectional image on a screen that rotates about a predetermined rotation axis Z has been mainly described. However, the present invention is not limited to this, and may be a volume scan that scans straight in a direction perpendicular to the projection plane of the screen. That is,
It is only necessary to scan a three-dimensional predetermined space by changing the position and / or posture of the screen.

In the above description, the screen 38
Although no particular mention was made of the material of the screen 3,
By devising the material of No. 8, the duty ratio at which the stereoscopic image is displayed can be doubled.

That is, although the volume scanning is completed by rotating the screen 38 by 180 °, when the screen 38 is made of an opaque material, the projection surface of the screen on which the cross-sectional image is projected is viewed from the observer. While facing to the back side (opposite side), the cross-sectional image cannot be visually recognized. Therefore, the duty ratio at which the stereoscopic image is displayed is １ ／. For this reason, after the end of the volume scanning, it is necessary to further rotate the screen 38 while the observer's eyes have an afterimage, and consequently it is necessary to rotate it by 360 °.

However, the material of the screen 38 has such a diffuse reflection performance that the projected image can be sufficiently viewed from the projection side, and at the same time, has a light transmittance that allows the image to be viewed from the back side of the screen 38. By using the material, the projected image can be visually recognized from both the front and back of the screen 38. Therefore, screen 38
The cross-sectional image can be visually recognized irrespective of the angle, and the duty ratio of the stereoscopic image display is 1. For this reason, the angle at which the screen 38 must be rotated within a time period in which the afterimage effect can be maintained is only 180 °. This allows
The number of rotations of the screen 38 can be reduced to １ ／, the angle of the cross-sectional image to be projected can be made finer by that amount, and the number of cross-sectional images can be increased to improve the quality of the stereoscopic image displayed. .

As the material of the screen 38, for example,
A translucent material such as frosted glass, frosted glass obtained by processing the surface of a transparent resin plate into frosted glass, or thin paper may be used.

[0155]

According to the first to fifth aspects of the present invention, the efficiency of data transfer to the storage means can be improved.

According to the third aspect of the present invention, the updating range of the cross-sectional image can be appropriately changed according to the size of the display object, and the cross-sectional image can be projected more efficiently.

According to the fourth aspect of the present invention, a high-definition stereoscopic image can be displayed according to the update range of the cross-sectional image.

According to the sixth and seventh aspects of the present invention, stereoscopic image display data suitable for reducing the amount of data transferred to the storage means can be obtained. 3D image display data suitable for appropriately changing the update range of.

[Brief description of the drawings]

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

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

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

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

FIG. 5 is a schematic perspective view of a screen and a rotating member.

FIG. 6 is a diagram showing the size (resolution) of a cross-sectional image projected on a screen.

FIG. 7 is a block diagram illustrating a functional configuration of the stereoscopic image display system.

FIG. 8 is a diagram illustrating a configuration example of a memory;

FIG. 9 is a diagram showing a configuration example of a memory according to the embodiment of the present invention;

FIG. 10 is a diagram in which main parts of the configuration shown in FIG. 7 are extracted.

FIG. 11 is a block diagram illustrating details of a memory control unit.

FIG. 12 is a block diagram illustrating a functional configuration of a host computer.

FIG. 13 is a diagram showing a conversion process from three-dimensional image data to two-dimensional image data.

FIG. 14 is a diagram illustrating an example of correction of a cross-sectional image (projected image).

FIG. 15 is a diagram showing a reading order from a memory according to a screen rotation angle θ.

FIG. 16 is a diagram illustrating an example of a control mechanism for switching a reading order of two-dimensional image data.

FIG. 17 is a diagram illustrating an example of an 8-bit horizontal address signal generated by an address generator.

FIG. 18 is a diagram illustrating a displayable area of the stereoscopic image display device.

FIG. 19 is a diagram illustrating an area in which display of a cross-sectional image is not updated.

FIG. 20 is a diagram showing a restricted area where the display of a cross-sectional image is updated.

21A is a diagram illustrating normal two-dimensional image data stored in a memory, FIG. 21B is a diagram illustrating two-dimensional image data stored in a limited storage amount area, and FIG. c)
FIG. 4 is a diagram showing a state in which a large amount of two-dimensional image data is stored in a memory by limiting a storage area.

FIG. 22 is a flowchart illustrating a processing procedure when a stereoscopic image is actually displayed on the stereoscopic image display device.

FIG. 23 is a flowchart illustrating a processing procedure when a stereoscopic image is actually displayed on the stereoscopic image display device.

FIG. 24 is a flowchart illustrating a processing procedure when a stereoscopic image is actually displayed on the stereoscopic image display device.

FIG. 25 is a diagram illustrating an example of the structure of stereoscopic image display data transferred to the stereoscopic image display device.

FIG. 26 is a flowchart illustrating another processing procedure when a stereoscopic image is actually displayed on the stereoscopic image display device.

FIG. 27 is a diagram illustrating another example of the structure of stereoscopic image display data transferred to the stereoscopic image display device.

FIG. 28 is a diagram illustrating the principle of a stereoscopic image display method using a volume scanning method.

[Explanation of symbols]

Reference Signs List 4 recording medium 33 DMD 38 screen 39 rotating member 50 projection optical system 60 DMD drive unit 63a, 63b memory 64 system controller 74 motor 82 read address generation unit 83 write address generation unit 100 stereoscopic image display device 801 802 stereoscopic image display data 812 , 822 Two-dimensional image data 813, 823 Update range data P1 to P4 Cross-sectional images S1 to S8, S81 to S86, S81a, S82a, S
84a step

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) G09G 5/00 550 G09G 5/00 550P 5/36 510 5/36 510V (72) Inventor Manami Kusako Osaka-shi, Osaka Osaka International Building Minolta Co., Ltd. 2-3-113 Azuchicho, Chuo-ku (72) Inventor Ken Yoshii Osaka International Building Minolta Co., Ltd. 2-72-13 Azuchicho, Chuo-ku, Osaka-shi, Osaka (72) Inventor Toshio Kaida F-term in Osaka International Building Minolta Co., Ltd. 2-13-13 Azuchicho, Chuo-ku, Osaka-shi, Osaka (reference) GG02 GG12 JJ01 JJ02 JJ04 JJ06 JJ07 5C082 AA01 BA12 BA34 BA47 BB15 BB26 BB42 BC05 CA76 CA84 DA51 MM02 MM10

Claims (7)

[Claims] 1. A stereoscopic image display method, comprising: (a) changing the position and / or orientation of a screen on which a cross-sectional image of a display object is projected to scan the screen; A plurality of two-dimensional image data is sequentially read from the storage means in synchronization with the scanning of the screen, and a plurality of cross-sectional images are sequentially projected on the screen based on the plurality of two-dimensional image data, so that a three-dimensional image of the display object is obtained. Displaying an image, wherein the step (b) restricts a range of data when at least one of the plurality of two-dimensional image data is written to and / or read from the storage unit. A step of limiting an update range when a corresponding cross-sectional image is projected. 2. A stereoscopic image display method, comprising: (a) changing the position and / or orientation of a screen on which a cross-sectional image of a display object is projected, thereby causing the screen to scan; Writing a two-dimensional image data group corresponding to at least one cross-sectional image of the display object to a storage unit; and (c) reading out the two-dimensional image data group from the storage unit in synchronization with scanning of the screen, Sequentially projecting the at least one cross-sectional image on the screen based on a two-dimensional image data group; and (d) repeating the steps (b) and (c) to sequentially display a plurality of cross-sectional images of the display object. Projecting, thereby displaying a stereoscopic image of the display object, at least before the step (b) is finally executed; (e) a two-dimensional image for the storage means Limiting the range of data at the time of writing and / or reading of the data group, thereby limiting an update range when at least one corresponding cross-sectional image is projected. Display method. 3. The stereoscopic image display method according to claim 2, further comprising: (f) changing the limited update range after the step (e). 3D image display method. 4. The stereoscopic image display method according to claim 2, wherein, after the step (e), (g) displaying one scene of the display object according to the limited update range. A stereoscopic image display method, further comprising the step of changing the number of sectional images to be constituted. 5. A three-dimensional image display device, comprising: a scanning unit that scans the screen by changing a position and / or a posture of a screen on which a cross-sectional image of a display object is projected, and synchronizing with the scanning of the screen. Projecting means for sequentially reading out a plurality of two-dimensional image data from the storage means while sequentially projecting a plurality of cross-sectional images on the screen based on the plurality of two-dimensional image data to display a three-dimensional image of a display object Limiting the range of data when at least one of the plurality of two-dimensional image data is written to and / or read from the storage unit, thereby limiting an update range when a corresponding cross-sectional image is projected. And a means for displaying a three-dimensional image. 6. The screen is scanned by changing the position and / or orientation of the screen, and a plurality of cross-sectional images of a display object are sequentially projected on the screen in synchronization with the scanning of the screen. A computer-readable recording medium recording stereoscopic image display data used when displaying a stereoscopic image of a display object, wherein the stereoscopic image display data is a cross-sectional image corresponding to a plurality of cross-sectional images of a display object. A computer-readable recording medium comprising: data; and update range data that substantially defines a range in which display should be updated when sequentially projecting the plurality of cross-sectional images. 7. The computer-readable recording medium according to claim 6, wherein the update range data defines a range in which display is to be substantially updated for each of the plurality of groups of the plurality of cross-sectional images. A computer-readable recording medium characterized by the following.