JPH0991468A - Three-dimensional image display device and its method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the 3-dimensional image display device and its method in which an object image is smoothly displayed even in a depth direction. SOLUTION: Color and luminance information at each point of a 3-dimensional image to be displayed is stored in a 3-dimensional image storage means 20, a coordinate of each point of the 3-dimensional image is converted into other 3-dimensional by an address conversion means 30 and a cross sectional image for each depth distance generated by the 3-dimensional image storage means 20 and the address conversion means 30 is stored in a cross sectional image storage means 40, the cross sectional image stored in the cross sectional image storage means 40 is displayed on a 3-dimensional image display means 50 for each depth and the end of display in the 3-dimensional image display means 50 is detected by a synchronization matching means 60 and display start is commanded.

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 device and method for electrically and smoothly displaying a stereoscopic image of an object or the like without using mechanical vibration or the like.

[0002]

2. Description of the Related Art Presently, three-dimensional image display is required in various applications. For example, it is used for shape design and correction in product design, and is necessary for virtually confirming the shape, size, function, etc. of the product even when there is no real product in the product display. Still others are needed in many fields such as virtual reality and immersive communication in video conferencing.

By the way, conventionally, when displaying an object as an image, a flat display device such as a cathode ray tube or a liquid crystal panel has been used. Since it is impossible to directly display an object having a three-dimensional shape in a three-dimensional manner on a flat display device, the object is represented by using a projection view in the upward direction or the side direction, or an overhead view of the object. Gives a three-dimensional effect. However, it is difficult for the observer to intuitively understand the three-dimensional shape and size of the object from these figures, and it is possible to grasp the three-dimensional shape and size of the object in the same way as when viewing an actual object. Various three-dimensional image display methods capable of performing the above have been devised.
For example, Takanori Ogoshi "3D Image Engineering", Shuichi Inada edited "3D Video", Chihiro Masuda "3D Display",
"Holographic Display," edited by Junpei Tsujiuchi, describes various 3D image display methods that have been devised so far.

The three-dimensional image display methods that have been proposed so far are large: (1) a method using stereoscopic vision (a method with or without glasses) (2) a method proposed by Benton et al. Of MIT (3) Method using holography (4) Method using moving light emitting surface (5) Method using depth sampling display.

As an example of (1), there is a method of using polarized glasses or glasses with a liquid crystal shutter when there are glasses. In addition, the head-mounted display, which has been actively developed recently, provides a right-eye image and a left-eye image in a form of being in close contact with the eyes and enables stereoscopic viewing. In principle, the method is the same as the method with glasses, but a method of giving a right-eye image and a left-eye image without wearing glasses has also been developed. An example thereof is a method using a lenticular lens array or a parallax barrier.

The method (2) is a method proposed by Benton et al. Of MIT (P. St. Hilaire, SA Benton, M. Lu).
cente, MLJepsen, J.Kollin, H.Yoshikawa and J.Underk
offer. "Electrronic display system for computationa
l display ", Proc.SPIE Vol.1212 (1990) pp.174-182). This is one laser beam scanned by an acousto-optic device and a three-dimensional image is formed using a galvano mirror and a polygon mirror. .

The method (3) is a method of recording and reproducing the object information by recording the interference fringes of the scattered light of the laser applied to the object and the reference light. For example, "Holographic Display" edited by Junpei Tsujiuchi. Is described in detail.

According to the method (4), the point light source elements are two-dimensionally arranged on one plane plate, and the plate is vibrated vertically or horizontally and rotated, and the object at each position is moved. This is a method of blinking each point light source according to the sectional shape of. For example, Kameyama has proposed a method of arranging LEDs two-dimensionally on a light emitting surface, moving the LEDs up and down, and blinking the LEDs according to the shape of an object to generate a stereoscopic image (K. Kameyama, K. .Ohtomi and
S.Sekimoto: "An interactive volume display system", T
AO first international symposium, E-5-2-E-5-4).

The method (5) is a method of arranging a display panel for each depth distance and displaying a cross-sectional image of the object at each depth distance to display a stereoscopic image of the object. For example, Tamura and Tanaka have proposed a device for displaying a stereoscopic image of an object by combining cross-sectional images displayed on a CRT display with a multidirectional beam splitter (S.
Tamura and K. Tanaka: "Multilayer 3-D display by mul
tidirectional beam splitter ", Appl.Opt.Vol.21 No.20
(1982) pp.3659-3663). As a method of displaying a stereoscopic image having a continuous depth with a simpler configuration, a method of arranging a plurality of liquid crystal panels at each depth distance and displaying a cross-sectional image on each of them is possible to display a stereoscopic image of an object. Invented by Nagatsu.

[0010]

However, each of the above methods has the following problems.

The method (1) has a problem that the eyes tend to get tired because a difference between the depth feeling due to the binocular parallax and the depth feeling due to the eye adjustment occurs. In addition to this, in the case of wearing glasses, there is a problem that a plurality of viewers cannot observe them. On the other hand, in the case without glasses, a plurality of observers can observe the images, but the method of giving the right-eye image and the left-eye image following the movement of the observers requires a complicated device configuration.

The method (2) has a movable part such as a galvanometer mirror and a polygon mirror, which causes a problem of reliability.
In addition, although a stereoscopic image is generated in advance on an electronic computer, it requires a very long calculation time. Although efforts have been made to use a high-speed computer and reduce the amount of calculation, when displaying an object of a real size, the amount of calculation is large and it is difficult to display the object in real time.

The method (3) is ideally the most desirable method. If a photographic dry plate is used, interference fringes can be recorded in the thickness direction of the emulsion, so that a large object with a sufficient sense of depth can be displayed, and the appearance changes naturally with changes in the viewpoint. However, in the case of a hologram on a photographic dry plate, since the process of the dry plate is included, the object cannot be displayed in real time. A method of displaying holograms in real time using a liquid crystal panel is considered, but the spatial resolution is low to record interference fringes, and it is not possible to record interference fringes in the thickness direction like a photo plate. Therefore, it is difficult to display an object with a sense of depth with one liquid crystal panel.

The method (4) is a sufficiently practical method even with the current technology. However, it is difficult for mechanical operation to vibrate and rotate the light emitting surface at high speed so that flicker does not occur, and reliability also becomes a problem. Further, there is a problem that the displayed image becomes a hollow image.

The method (5) is the second most practical method after the method (4). However, in the method proposed by Tamura and Tanaka, the number of images combined by one beam splitter is limited to 5, so it is necessary to increase the number of beam splitters in order to increase the images in the depth direction.
In this case, it is not practical because it physically takes up space. On the other hand, as described above, the method proposed by Nagatsu is that the liquid crystal panels are arranged in the depth direction in principle, except for restrictions due to the transmitted light intensity and the physical thickness of the liquid crystal panel because the liquid crystal panels are arranged in a stack. It is possible to arbitrarily increase the number of.

However, even with this method, it is difficult to make the intervals of the depth method sufficiently small. For example, since the pixel size of the liquid crystal panel is 1 mm or less, the cross-sectional image can be displayed smoothly with a fineness of about 1 mm. On the other hand, if the liquid crystal panels are arranged at intervals of 1 mm in the depth direction, it is necessary to display an object with a size of 10 cm.
This requires 00 liquid crystal springs, which is difficult in reality. On the other hand, if the gap is set to about 5 mm, only 20 liquid crystal panels are required, which is a method that can be sufficiently realized. However, the display interval in the depth direction is larger than that of the display pixels of the cross-sectional image of the liquid crystal, and the object image displayed in the depth direction becomes a very rough image compared to the smoothness of the cross-sectional image, and the three-dimensional shape of the object is It becomes difficult to grasp.

As a method of solving the problem, the above-mentioned method of Nagatsu proposes a method of smoothly displaying an object image also in the depth direction by vibrating the image display device itself by the display interval in the depth direction. ing. However, in this case, the same problem as in the above (4) will occur.
That is, it is difficult to operate the display device fast enough so that flicker does not occur, and reliability is also a problem.

The present invention has been made in view of the above,
An object of the invention is to provide a three-dimensional image display device and method capable of displaying an object image smoothly also in the depth direction.

[0019]

In order to achieve the above object, the present invention according to claim 1 is a three-dimensional image display device for stereoscopically displaying an image, wherein each of three-dimensional object images to be displayed. Three-dimensional image storage means for storing color and luminance information at points, address conversion means for converting the coordinates of each point of the three-dimensional object image into other three-dimensional coordinates, the three-dimensional image storage means and the address conversion means. Section image accumulating means for accumulating the sectional image for each depth distance generated by, the three-dimensional image display means for displaying the sectional image accumulated in the sectional image accumulating means for each depth distance, and the three-dimensional image. The gist of the present invention is to have a synchronization means for detecting the display end on the display means and instructing the three-dimensional image display means to start the display.

According to the first aspect of the present invention, the color and luminance information at each point of the three-dimensional object image stored in the three-dimensional image storage means and the coordinates of each point of the three-dimensional object image are converted by the address conversion means. Further, a cross-sectional image for each depth distance generated from another three-dimensional coordinate is accumulated, and the accumulated cross-sectional image is displayed for each depth distance by the control of the synchronization means, so that the time-varying object image is continuously displayed. Is displayed.

The present invention described in claim 2 provides the present invention in claim 1.
The gist of the invention described above is to have a vibration / rotation display means for displaying the three-dimensional object image while vibrating it in the front, rear, left, and right directions, or displaying it with rotation.

According to the second aspect of the present invention, the three-dimensional object image is displayed while being oscillated in the front-rear direction and the left-right direction, or is displayed with rotation, so that a smooth display is performed.

Further, the present invention according to claim 3 provides the invention according to claim 2.
In the invention described above, the gist is that the address conversion means only performs coordinate conversion of points of a three-dimensional object image belonging to a cross-sectional image generated during display by the vibration / rotation display means.

According to the third aspect of the present invention, the address conversion means performs only the coordinate conversion of the points of the three-dimensional object image belonging to the sectional image generated during display.

According to a fourth aspect of the present invention, in the inventions according to the first to third aspects, the three-dimensional image display means includes a plurality of display panels provided in parallel in the depth direction at predetermined intervals, and the plurality of display panels. And a plurality of display control means for controlling the display of the corresponding display panel, wherein the cross-sectional image storage means is provided corresponding to each of the plurality of display panels. The gist of the present invention is to have a plurality of memory means for respectively storing cross-sectional images corresponding to the depth distances provided in the respective display panels.

In the present invention according to claim 4, a plurality of display panels are provided in parallel in the depth direction at predetermined intervals, and sectional images respectively corresponding to the plurality of display panels are accumulated by a plurality of memory means. There is.

According to a fifth aspect of the present invention, there is provided a three-dimensional image display method for stereoscopically displaying an image, in which color and luminance information at each point of the displayed three-dimensional object image is stored. The coordinate of each point of the three-dimensional object image is converted into another three-dimensional coordinate, and the color and luminance information of each point of the stored three-dimensional object image and the depth distance generated by the converted three-dimensional coordinate are calculated. Cross-sectional images are accumulated, the accumulated cross-sectional images are displayed for each depth distance, and a three-dimensional object image is displayed.
The gist is to detect the display end of the cross-sectional image and to give an instruction to start the display.

In the present invention according to claim 5, the color and luminance information stored for each point of the three-dimensional object image and the coordinate of each point of the three-dimensional object image are generated from another transformed three-dimensional coordinate. Cross-sectional images are accumulated for each depth distance, and the accumulated cross-sectional images are displayed for each depth distance to display a three-dimensional object image.

Furthermore, the present invention according to claim 6 provides the invention according to claim 5.
In the invention described above, the gist is that the three-dimensional object image formed by the cross-sectional images displayed for each depth distance is displayed while being electrically vibrated in the front, rear, left and right, or is displayed with electrical rotation. To do.

According to the sixth aspect of the present invention, the three-dimensional object image displayed by the cross-sectional image displayed for each depth distance is displayed while being electrically vibrated back and forth, left and right, or accompanied by electrical rotation. indicate.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a three-dimensional image display device according to an embodiment of the present invention. A three-dimensional image display device 10 shown in the figure includes a three-dimensional image storage unit 20 that stores information such as color and brightness at each point of an object,
Address conversion means 30 for converting the coordinates of each point of the object to another new three-dimensional coordinate, cross-sectional image storage means 40 for accumulating the generated cross-sectional image for each depth distance, and displaying the cross-sectional image for each depth distance. The three-dimensional image display means 50 for stereoscopically displaying the object and the synchronization means 60 for performing synchronous control of the image display of the three-dimensional image display means 50 are provided.

In the three-dimensional image display device configured as described above, the three-dimensional image storage means 20 stores information such as color and brightness at each point of the object. The coordinates of each point of the object are converted into new coordinates by the address conversion means 30, and the sectional image in the depth direction is stored in the sectional image storage means 40.
The three-dimensional image display means 50 displays the cross-sectional images in the depth direction accumulated in the cross-sectional image accumulating means 40 and stereoscopically displays the object. The synchronization unit 60 monitors whether the three-dimensional image display unit 50 is displaying an image, and after receiving the signal indicating the completion of display from the three-dimensional image display unit 50, executes another object image display 3 A display start signal is transmitted to the three-dimensional image display means 50.

FIG. 2 is a block diagram showing a more specific structure of the three-dimensional image display device shown in FIG. The three-dimensional image display device 100 shown in the figure corresponds to the three-dimensional image storage unit 200 corresponding to the three-dimensional image storage unit 20 in FIG. 1, the address conversion unit 300 corresponding to the address conversion unit 30, and the cross-sectional image storage unit 40. The cross-sectional image storage unit 400, the three-dimensional image display unit 500 corresponding to the three-dimensional image display unit 50, and the synchronization unit 600 corresponding to the synchronization unit 60 are included.

The three-dimensional image storage unit 200 stores information such as color and brightness at each point of the object, and may be an ordinary memory. The three-dimensional image is stored as voxel data as shown in FIG. That is, assuming that the spatial coordinates are left-handed and the coordinates are x, y, z, the voxel v (x,
The color and luminance information of this point is stored in y, z). FIG.
Then, the coordinates are x = (− Nx) / 2, ..., (Nx / 2),
y = (-Ny) / 2, ..., (Ny / 2), z = (-N
z) / 2, ..., (Nz / 2). On the other hand, the subscript of a normal three-dimensional array is an integer starting from 0. However, the subscripts of the three-dimensional array are i, j, and k

## EQU1 ## v (x, y, z) = v (i-Nx / 2, j-N
If y / 2, k-Nz / 2) is set, the coordinates can be associated with each other, so that no problem occurs. Therefore, description will be given below using the coordinate system of FIG.

The address conversion unit 300 generates a cross-sectional image for each depth distance displayed on the three-dimensional image display unit 500 from the three-dimensional object image stored in the three-dimensional image storage unit 200. That is, voxel data {v (x, y,
z)} address (coordinates x, y, z) is converted into a cross-sectional image address to generate a cross-sectional image. Three-dimensional image storage unit 20
Although the coordinates of the voxel data stored in 0 are continuous, the three-dimensional image display unit 500 can display only a sectional image with a limited depth distance in the depth direction. The address conversion unit 300 samples an image in the depth distance direction from the voxel data of the three-dimensional image storage unit 200 to generate a cross-sectional image. Further, when the object displayed on the three-dimensional image display unit 500 is vibrated or rotated, the coordinates of the voxel data are converted into new coordinates for the three-dimensional image display unit 500, and a cross-sectional image for each depth distance is obtained. To generate. The details will be described later.

The sectional image storage section 400 stores sectional images for each depth distance, and may be a memory having a capacity capable of storing a plurality of sectional images. In the case of FIG. 2, the memory 40
1, 402, 403, 404. This is 3
Display panels 501, 502, 5 of the three-dimensional image display unit 500
03, 504, display control units 511, 512, 513, 5
The number corresponding to 14 is provided, for example, the memory 4
01 is provided corresponding to the display panel 501 and the display control unit 511.

The three-dimensional image display unit 500 displays an object three-dimensionally, and in FIG. 2, four display panels 501, 502, 503, 504 provided in the depth direction and its display control unit 511. It is composed of 512, 513 and 514.

Display panels 501, 502, 503, 50
4 displays a cross-sectional image for each depth distance, and C
Examples include RTs and liquid crystal panels. Display control units 511, 51
2, 513 and 514 are processors or display circuits. The display control units 511, 512, 513, 514 correspond to the liquid crystal panels 501, 502, 503, 504, respectively. If the display control unit 511 is the memory 4,
The cross-sectional image is read from 01 and the image is displayed on the display panel 501. In FIG. 2, the number of display panels is four, but the number of display panels may actually be larger. For example, when displaying an object having a depth of 10 cm on a display panel having a depth distance of 5 mm, 20 display panels are required.

FIG. 3 is a diagram showing an example of the configuration of the three-dimensional image display unit. The example of FIG. 3 (a) is a method proposed by Tamura and Tanaka, and is a distance L from the multidirectional beam splitter BS.
Emissive display panels D1, D2 and D3 are placed at positions separated by 1, L2 and L3, respectively. The images displayed on the light emitting display panels D1, D2, D3 are combined by the multi-directional beam splitter BS and observed by an observer. At this time, since the image of the display panels D1, D2, D3 appears to the observer at the distances L1, L2, L3 behind the beam splitter BS as shown in FIG. 3B, the object is stereoscopic. Can be observed. However, in this method, as described above, one multi-directional beam splitter B
With S, the number of images that can be combined at one time is less than 5, and if the number of depth images is further increased, it is necessary to increase the number of multidirectional beam splitters, resulting in a large apparatus.

FIG. 4 is a diagram showing another example of the configuration of the three-dimensional image display unit, which is proposed by the method of Nagatsu mentioned above. The illumination light S passes through the polarizer P2 and the transmissive liquid crystal panels D3, D2 and D1. After that, the polarizer P
An image is observed by an observer through a polarizer P1 which allows a polarized light orthogonal to 2 to pass therethrough. At this time, the observer actually observes the cross-sectional image displayed at each depth distance, and thus can observe the three-dimensional object image.

Returning to FIG. 2 again, description will be made. The synchronization unit 600 includes a synchronization signal reception unit 601 and a synchronization signal transmission unit 602.
Consists of In the synchronization signal receiving unit 601, the display control units 511, 512, 513, and 514 are the display panels 501.
A display end signal transmitted when the display of the sectional images on 502, 503, and 504 is completed is received. Display control unit 511
Since the time required for 512, 513, and 514 to display the cross-sectional image varies, the synchronization signal receiving unit 601 determines that the display ends when the display end signals are received from all the display control units.

The synchronization signal sending unit 602 sends the display start signal of another object image only after the display is finished, and the display control units 511, 5 are provided.
It is sent to 12,513,514. Display control unit 511
When the display start signals are received, the display devices 512, 513, and 514 start displaying another stereoscopic image, so that the display of a plurality of display panels can be synchronized.

Next, the three-dimensional image display method according to the present invention will be described. The three-dimensional image display device of the present invention has a plurality of display panels arranged in the depth direction and displays a cross-sectional image for each depth distance. Since the display interval in the depth direction is coarser than that of the pixels, the displayed stereoscopic image is not smooth in the depth direction, resulting in an image that is inconvenient for grasping the shape of the stereoscopic image. As a method of solving the problem, in the method of Nagatsu described above, by vibrating the image display device itself by the display interval in the depth direction, the cross-sectional image of the depth distance that could not be displayed is displayed, and the object image is smoothed. Suggests a way to display. However, it is difficult to operate the display device fast enough so that flicker does not occur, and reliability is also a problem.

On the other hand, in the three-dimensional image display method of the present invention, the displayed object is not moved but displayed by vibrating back and forth, or by rotating and displaying. By displaying a cross-sectional image at a depth distance that could not be displayed in the object image, the object image is smoothly displayed in the depth direction, and the three-dimensional shape of the object image can be easily grasped.

FIG. 5 is a diagram showing a vibration display method of a three-dimensional image. Consider a case where a wedge-shaped object is displayed on nine display panels arranged in the depth direction. FIG. 5 (b)
In (e), the sides of the wedge-shaped object extending in the depth direction are also continuously connected, but in reality, each cross-sectional image is displayed as a point as shown in FIG. Observed as connected. Here, the wires are continuously connected for the sake of explanation. 5 (b) to (e),
The wedge-shaped object drawn with a thin dotted line shows the position of the object displayed one time before, and the wedge-shaped object with a thick dotted line shows the position of the object displayed at the current time. As shown in the figure, the display surface of the three-dimensional image display device does not vibrate, and the object image is repeatedly displayed while vibrating in the order of (b) → (c) → (d) → (e) → (a). It In this way, since the cross-sectional image at the depth distance that could not be displayed in the state of FIG. 5B is displayed by the vibration display, the shape of the wedge-shaped object that vibrates back and forth due to the afterimage is smoothly observed.

6A to 6D and 7E to 7E.
(H) is a figure which shows the rotation display method of a three-dimensional image.
Consider a case where a wedge-shaped object is displayed on nine display panels arranged in the depth direction as in FIG. Figure 6
In (a) to (d) and FIGS. 7 (e) to (h), the wedge-shaped object drawn with a thin dotted line indicates the shape and position of the object displayed in the initial state, and the wedge-shaped object has a thick dotted line. The wedge-shaped object indicates the shape and position of the object displayed at the current time. As shown in the figure, the display surface of the three-dimensional image display device does not rotate,
Wedge-shaped object image is (a) → (b) → (c) → (d) →
(E)->(f)->(g)->(h)-> (a) ... is displayed while rotating by 45 [deg.] Counterclockwise. In this way, since the cross-sectional image at the depth distance of the object is displayed in a state different from the state of FIG. 6A by the rotation display, it becomes easy to grasp the shape of the wedge-shaped object.

Now, referring to FIG. 2, the sectional image accumulating section 400 is shown.
Has memories 401 to 404 for accumulating cross-sectional images corresponding to the respective display panels 501 to 504 and display control units 511 to 514. 5A to 5E, 6A to 6D, and 7A to 7D in the memories 401 to 404 in advance.
The cross-sectional images at the corresponding depth distances of the three-dimensional object images (e) to (h) may be accumulated. When the object image at a certain time is displayed on the three-dimensional image display unit 500, the synchronization signal receiving unit 601 displays all the display panels 501 to 504.
Waits until it receives a display end signal indicating that the display has ended from the display control units 511 to 514, and when the display ends, the display control unit 5 starts displaying the image at the next time.
By sending the display start signal to 11 to 514 from the synchronization signal sending unit 602, the vibrating or rotating object image can be continuously displayed.

In the following, with respect to the vibration and rotation display of the object image shown in FIGS. 5, 6 and 7, an address conversion method performed by the address conversion unit 300 of FIG. 2 for generating a sectional image will be described. The voxel data representing the object image is shown in FIG.
I took the coordinates like, but after that, for simplicity, Nx
= Ny = Nz = N.

FIG. 9 is a diagram for explaining a method of extracting a cross-sectional image when a three-dimensional image is vibratingly displayed. The sampling interval of the cross-sectional image in the depth (x-axis) direction is n. It is assumed that the center of the display object is in the center of the display device in the initial state. At this time, kth from the center (k = 0, ± 1, ± 2, ± 3, ...
If the cross-sectional image of () is d _k (y, z), then d _k (y, z) = v (kn, y, z).

On the other hand, if the center of gravity of the object is deviated by s, then d _k (y, z) = v (kn + s, y, z).

Next, an address conversion method for rotation will be described. FIG. 10 is an explanatory diagram for obtaining a cross-sectional image when the display object is rotated around the z axis. It is assumed that the xy axes rotate counterclockwise about the z axis by θ. In this case, the display object is equivalent to rotating clockwise by (−θ).

FIG. 10A is an explanatory view for obtaining a sectional image at a distance kn from the center. The hatched plane is a sectional image separated from the center by a distance kn. Sectional image d _k
On (y, z) = v (x, y, z), between the coordinates x and y, the geometrical shape on the xy plane of FIG.

(2) (x−kn cos θ) / (− sin θ) = (y−kn sin θ) / cos θ (1). Also, the coordinates of the end points (x1, y
1) and (x2, y2) are

X1 = kn cos θ + N / 2 sinα sin θ (2-1) y1 = kn sin θ−N / 2 sin α cos θ (2-2) x2 = kn cos θ−N / 2 sin α sin θ (2-3) y2 = kn sin θ + N / 2 sin α cos θ (2-4). α is

## EQU00004 ## .alpha. = Cos.sup.- ¹ (2kn / N) (2-5).

From FIG. 10A, the range on the z axis is

## EQU00005 ## z1 = N / 2 (3-1) z2 = -N / 2 (3-2).

As described above, the range of the sectional view is determined only by the values of n, N and θ. Therefore, if the method of obtaining the cross-sectional image is written programmatically, if x1 ≠ x2,

Δx = sgn (x2-x1); Δy = (y2-y1) / (x2-x1); Δz = sgn (z2-z1); for (x = x1; x = x2; x = x + Δx) {Y = y1 + (y−y1) Δy; (4) for (z = z1; z = z2; z = z + Δz) {d _k (y, z) = v (x, y, z);}} Good. When x1 = x2,

Δy = sgn (y2-y1); Δz = sgn (z2-z1); for (y = y1; y = y2; y = y1 + Δy) {for (z = z1; z = z2; z = z + Δz ) {(5) d _k (y, z) = v (x1, y, z);}}. Here, sgn (x) in equations (4) and (5)
Is a function that takes the sign of x.

FIG. 11 is an explanatory diagram for obtaining a cross-sectional image when rotation conversion is performed around an arbitrary axis. Here it is assumed that the object is cylindrical. Considering the case where the x-axis rotates by θ in the counterclockwise direction and the z-axis rotates by φ in the clockwise direction as shown in FIG. 11A, the equation of the center line oo ′ is

Xc / (sin θ cos φ) = yc / (cos θ cos φ) = (zc−kn / cos φ) / (− sin φ) (6) Here, the possible values of z are

Z1 = kn cosφ + N / 2 sinφ (7-1) z2 = kn cosφ−N / 2 sinφ (7-2). In the cross-sectional image separated by a distance kn from the center,
The coordinates (x1, y1), (x2, y2) of the end points are

X1 = xc + N / 2 sinα sinθ (8-1) y1 = yc−N / 2 sinα cosθ (8-2) x2 = xc−N / 2 sinα sinθ (8-3) y2 = yc + N / 2 sinα cos θ (8-4). α is

[Expression 11] α = cos ^-1 (2kn / N) (8-5) This is the angle obtained.

Therefore, the method of obtaining the sectional image separated from the center by the distance kn is as follows. First, zc is continuously changed from z1 to z2. For some value of zc,
The values of xc and yc are obtained from the equation (6). Next, the end points (x1, y1), (x2, y2) of the cross-sectional image are (8-1) to
It is calculated by the equation (8-5). The value of (x, y) is changed to (x
1, y1) to (x2, y2) while changing d _k
It is sufficient to take the value of (y, zc) = v (x, y, zc).

FIG. 12 is an explanatory diagram for obtaining a cross-sectional image when rotation conversion is performed around an arbitrary axis. However, unlike FIG. 11, it is considered that the object is spherical. FIG.
Assuming that the x-axis is rotated counterclockwise by θ and the z-axis is rotated clockwise by φ as shown in (a), and assuming that the cross section is circular, the equation of the center line oo ′ is expressed by equation (6). As well as

Xc / (sin θ cos φ) = yc / (cos θ cos φ) = (zc−n / cos φ) / (− sin φ) (9) However, the possible values of z are

Z1 = kn cosφ + N / 2 sinα sinφ (10-1) z2 = kn cosφ−N / 2 sinα sinφ (10-2). Where α is

[Mathematical formula-see original document] [alpha] = cos- ¹ (2kn / N) (10-3). In the cross-sectional image separated by a distance kn from the center,
The coordinates (x1, y1), (x2, y2) of the end points are

X1 = xc + N / 2 sinβ sinθ (11-1) y1 = yc-N / 2 sinβ cosθ (11-2) x2 = xc-N / 2 sinβ sinθ (11-3) y2 = yc + N / 2 sinβ cos θ (11-4). β is

## EQU16 ## β = cos ^-1 (2 kr / N) (11-5) r = (x ² + y ² + zc ² ) ^1/2 (11-6) This is the angle obtained.

Therefore, the method of obtaining the sectional image separated from the center by the distance kn is as follows. First, zc is continuously changed from z1 to z2. For some value of zc,
The values of xc and yc are obtained from the equation (9). Next, the end points (x1, y1), (x2, y2) of the cross-sectional image are (11-1)
It is calculated by the equation (11-6). It is sufficient to take the value of d _k (y, zc) = v (x, y, zc) while changing the value of (x, y) from (x1, y1) to (x2, y2). . In this case, (11-5), (11
Since zc is related to the value of β from equation (6), the calculation becomes more difficult than in the case of FIG.

If the coordinate conversion described above is implemented as hardware logic in the address conversion unit 300 of FIG. 2, only the coordinates of the points included in the sectional image are converted and 3
It is converted into the coordinates of the voxel data stored in the three-dimensional image storage unit 200, and only the color and brightness information of that point is extracted. Therefore, the sampling interval n in the depth direction
Is larger, the number of coordinate conversions performed by the address conversion unit can be reduced, and the cross-sectional image can be generated at high speed.

[0061]

As described above, according to the present invention,
Depth distance generated from color and brightness information at each point of the three-dimensional object image stored in the three-dimensional image storage means and another three-dimensional coordinate obtained by converting the coordinates of each point of the three-dimensional object image by the address conversion means. Since the cross-sectional images for each are accumulated and the accumulated cross-sectional images are displayed by the control of the synchronization means for each depth distance, it is possible to continuously display the object image that changes with time.

Further, since the three-dimensional object image is displayed while being oscillated in the front-rear and left-right directions, or is displayed while being rotated, information is provided in the three-dimensional image display device having a rough sampling interval in the depth direction. It is possible to display various object images.

Further, regarding the vibration display and rotation display of the three-dimensional object image, the address conversion means only performs the coordinate conversion of the points of the three-dimensional object image belonging to the generated sectional image, so that the sectional image to be displayed at high speed can be obtained. Can be generated.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a three-dimensional image display device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a more specific configuration of the three-dimensional image display device shown in FIG.

FIG. 3 is a diagram showing a configuration example of a three-dimensional image display unit.

FIG. 4 is a diagram showing another configuration example of a three-dimensional image display unit.

FIG. 5 is a diagram illustrating a vibration display method of a three-dimensional image.

FIG. 6 is a diagram illustrating a rotation display method of a three-dimensional image.

FIG. 7 is a diagram illustrating a rotation display method of a three-dimensional image.

FIG. 8 is a diagram illustrating a storage format of a three-dimensional image.

FIG. 9 is a diagram illustrating a cross-sectional image extraction method when a three-dimensional image is displayed in vibration.

FIG. 10 is a diagram illustrating a cross-sectional image extraction method when rotating and displaying a three-dimensional image around the z axis.

FIG. 11 is a diagram illustrating a cross-sectional image extraction method when a three-dimensional image is arbitrarily rotated and displayed when an object has a cylindrical shape.

FIG. 12 is a diagram illustrating a cross-sectional image extraction method when a three-dimensional image is arbitrarily rotated and displayed when an object is spherical.

[Explanation of symbols]

 10, 100 three-dimensional image display device 20 three-dimensional image storage means 30 address conversion means 40 cross-sectional image storage means 50 three-dimensional image display means 60 synchronization means 200 three-dimensional image storage unit 300 address conversion unit 400 cross-sectional image storage unit 401, 402, 403, 404 memory 500 three-dimensional image display section 501, 502, 503, 504 display panel 511, 512, 513, 514 display control section 600 synchronization unit 601 synchronization signal reception section 602 synchronization signal transmission section

Claims (6)

[Claims] 1. A three-dimensional image display device for stereoscopically displaying an image, comprising: a three-dimensional image storage means for storing color and luminance information at each point of the displayed three-dimensional object image; and a three-dimensional object image. Address conversion means for converting the coordinates of each point into another three-dimensional coordinate, and sectional image storage means for storing sectional images for each depth distance generated by the three-dimensional image storage means and the address conversion means, Three-dimensional image display means for displaying the cross-sectional images stored in the cross-sectional image storage means for each depth distance, and detection of display end in the three-dimensional image display means,
A three-dimensional image display device comprising: a three-dimensional image display means and a synchronization means for instructing the three-dimensional image display means to start display. 2. The vibration / rotation display means for displaying the three-dimensional object image while vibrating it in the front-rear and left-right directions, or displaying it with rotation.
Dimensional image display device. 3. The address conversion means belongs to a cross-sectional image generated during display by the vibration / rotation display means.
3. The three-dimensional image display device according to claim 2, wherein only the coordinate conversion of the points of the three-dimensional object image is performed. 4. The three-dimensional image display means includes a plurality of display panels arranged in parallel in the depth direction at predetermined intervals,
A plurality of display control units that are provided corresponding to the plurality of display panels, respectively, and that control the display of the corresponding display panels; and the cross-sectional image storage unit is provided corresponding to the plurality of display panels, respectively. 4. The three-dimensional image display device according to claim 1, further comprising a plurality of memory means for accumulating the sectional images corresponding to the depth distances provided in the respective display panels. 5. A three-dimensional image display method for stereoscopically displaying an image, wherein color and brightness information at each point of a displayed three-dimensional object image is stored, and coordinates of each point of the three-dimensional object image are stored. The image is converted into another three-dimensional coordinate, and the color and brightness information of each point of the stored three-dimensional object image and the cross-sectional image for each depth distance generated by the converted three-dimensional coordinate are accumulated. Display the cross-sectional image for each depth distance 3
A three-dimensional image display method comprising displaying a three-dimensional object image, detecting the display end of the cross-sectional image, and instructing the display start. 6. A three-dimensional object image formed by cross-sectional images displayed for each depth distance is displayed while being electrically vibrated in the front, rear, left and right, or is displayed with electrical rotation. The three-dimensional image display method according to claim 5.