JPS62145375A - Three-dimensional display device - Google Patents

Abstract

PURPOSE:To easily display the cross section position of a stereoscopic image in a short time by performing the addition and subtraction of a parallel projection image until when an designated cross section is displayed. CONSTITUTION:The parallel projection image in which a tomographic image is projected in an optional direction with an affine transformation device is generated, and a restructured image is generated by adding the tomographic image with an addition/subtraction device. Next, all of the tomographic images of a three-dimensional stereoscopic image are affine-transformed and an added perfect reprojection image is set as 0. First of all, a tomographic image 1 at the upmost part of the three-dimensional stereoscopic image is affine- transformed, and a parallel projection image 1 is constituted, and when the image is subtracted from the reprojection image 0, the reprojection image of which the upmost part is cut off, can be obtained. By repeating in order the processing, a reprojection image (n) can be obtained as the reprojection image in which the tomographic image from the upmost part to the n-th number of part are cut off from the three-dimensional stereoscopic image. Also, by adding the tomographic image at the n-th number on the reprojection image (n), a reprojection image (n-1) can be generated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention 1] The present invention relates to a three-dimensional display device that can perform three-dimensional display at high speed using a reprojection method.

[Technical background of the invention and its problems 1 The reprojection method, which is one of the conventional three-dimensional display methods, requires adding all three-dimensional images to an arbitrary projection plane. It took some time to display the cross section.

In addition, when displaying a 3D image on a display device such as a CRT, since the CRT is a 2D plane, it is difficult to specify the direction in which the 3D image will go when displayed, and it is difficult to specify the direction in which the 3D image will go when displayed. It has been difficult to visually indicate the point or measure the distance between two points in a short time.

[Objective of the Invention 1] The present invention has been made in view of the above-mentioned circumstances, and improves the conventional reprojection method to cut out or stack each tomogram and display the positional relationship of tomograms in three-dimensional space. The purpose of the present invention is to provide a three-dimensional display device that allows the user to intuitively grasp the information, roughly display the positional relationship of arbitrary points in a three-dimensional space, and enable three-dimensional measurement of these points in a short time. .

SUMMARY OF THE INVENTION 1 In order to achieve the above-mentioned object, the present invention provides a memory storage system for storing 1A'Jj layer images constructed by data collection or tomographic images constructed by interpolation based on these tomographic images. an affine transformation device that performs affine transformation on each tomographic image in a desired direction to create a parallel projection image; and an affine transformation device that adds the parallel projection images to create a reprojection image; An addition/subtraction device capable of adding and subtracting the parallel projection image, a display device displaying the IA reprojection image, and a puff 3 means for specifying and inputting an arbitrary cross section of the reprojection image displayed on the display device,
Until the section specified by this input means is displayed;
This device is characterized by performing h0 calculation of a parallel projection image using a 11I numbing device.

[Embodiment 1 of the Invention Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a circuit block diagram showing one embodiment of the present invention.

In FIG. 1, 1 is a storage device that stores at least a reprojection image created based on a tomographic image and a tomographic image of the mouth, and 2 is a storage device that interpolates between a plurality of tomographic images stored in the storage device to create a new one. 3 (J) is an affine transformation device that performs one affine transformation on the tomographic image (including interpolated images) to create a parallel projection image; 4 is the affine transformation device; /JLI'D the parallel projection image projected by ii7 to create a reprojection image, and adjust the parallel projection image to this reprojection image.
5 is a coordinate input device such as a trackball, joystick, digitizer, etc. for inputting various coordinate positions on the tomographic image or reprojection image; 6 is a coordinate input device that can be assigned to the display device; A keyboard is used to input information as to whether the parallel projection image is to be JJn R or subtracted in order to display the cross section, and 7 is a display device that displays the tomographic image stored in the storage device or the reprojection image. .

Next, the operation of the three-dimensional display device according to the present invention configured as described above will be explained. First, the operation of the interpolation processing device 2 will be explained using FIG. FIG. 2 shows a three-dimensional stereoscopic image composed of a plurality of tomographic images, and since this three-dimensional stereoscopic image is data net-determined in the slice pitch direction only with the tomographic images constructed by data collection, the interpolation device is used to create a new three-dimensional image. Creating a tomographic image. It should be noted that if a sufficient number of tomographic images are ISlized in the slice pitch direction by data collection, interpolation processing is not necessary, and therefore, this interpolation processing device is not necessarily an essential component.

Next, the image display operation of the apparatus of this embodiment will be explained with reference to FIG. FIG. 3 shows the display of the re-projected image on the display device, in which a parallel projection image is created by projecting the tomographic image in an arbitrary direction by the affine transformation device, and these tomographic images are added by the addition and subtraction device. Create a reconstructed image. Note that if you want to change the direction of projection, you can change the projection direction arbitrarily by changing the affine transformation variables of the affine transformation device 3.

Next, in FIG. 4, all the tomographic images of the three-dimensional stereoscopic image are subjected to affine transformation, and a complete reprojected image obtained by adding them is designated as O.

First, the topmost tomographic image 1 of the three-dimensional stereoscopic image is subjected to affine transformation, a parallel projection image 1 is formed tM, and this image is reprojected as O
Subtracting from gives a truncated reprojection fm1. By repeating this process one after another, a reprojection image can be created in which the n-th tomographic image from the top of the three-dimensional stereoscopic image is deleted. Moreover, the reprojection image n1. = By adding and subtracting the n-th tomographic image, a reprojected image (n=1> can be created. In this way, as shown in FIG. 5, the affine-transformed tomographic images, that is, the parallel projected images are added. If you specify whether to subtract or subtract, and display the reprojected image on the display device 7 each time,
When subtraction is specified, the currently displayed reprojection image n can be displayed as being gradually cut out, and conversely, when addition is specified, the currently displayed reprojection images are gradually stacked on top of each other. can be displayed. The above-mentioned information on whether to add or subtract is input from the keyboard 6, but it is not limited to such a designation, and any addition or subtraction can be performed by designating the cross-sectional position.

Such a display makes it easy to specify an arbitrary cross section of the stereoscopic image. Further, in this embodiment, arbitrary coordinates on the arbitrary cross section can be easily specified. That is, cut/stack display S: Repeat the position of the tomographic image at point 94 and stop the display.If the cursor is displayed at the same time and this cursor is controlled by the coordinates tiδ5, it, II. , it is possible to specify an arbitrary position in the topmost tomographic image of the currently displayed reprojected image.

Next, as shown in FIG. 6, if the reprojection image and the tomographic image are displayed simultaneously, the position coordinates in the three-dimensional space can be uniquely specified. That is, if the currently displayed reprojected image is defined as the top tomographic image, the coordinates of the Z axis are determined, and the coordinates of the X and Y axes are determined from the tomographic image.

Next, Fig. 7 (A') ([3> is a diagram showing the method of measuring the distance between two points. As mentioned above, the square point A is shown as the reprojected image on the left and the tomographic image on the right. Next, define point B in the same way. In this case, point A and point B are displayed twice.

On the other hand, FIG. 8 shows points A and B on the same art dealer.

Also, when displaying the re-projected image, if you perform image conversion such as window conversion, you can brighten the visible parts. In addition, when creating a reprojected image using the subtraction device 4, it is possible to cast a μλ shadow in the 11 inner directions by covering the hand.

As mentioned above, according to this embodiment, when cutting out a three-dimensional object of each :hl+r) layer, that is, an nxnxrlBL field, using the vi projection method, the number of affine transformations is n in the case of this embodiment.
In the conventional case, it is nxnx(n-1) times. Therefore, in the case of this embodiment, compared to the conventional case, the number of affine transformations is 1/(n-1), which is 1, and the pixel addition time is 2n hours in the case of this embodiment, compared to the conventional case. is nxnx(n-1) time. Therefore, the pixel activation time is -b2/(n-1).

Furthermore, by cutting the middle part of one slice or stacking them continuously, it is possible to easily specify a point in three-dimensional space and measure the distance between two points in a short time.

U Effect of the Invention 1 As explained above, according to the present invention, the cross-sectional position of a three-dimensional image can be displayed easily and in a short time, and roughly, it is easy to specify arbitrary coordinates in a three-dimensional space. Therefore, it is possible to provide a three-dimensional display device that can perform three-dimensional measurement in a short time.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of a three-dimensional display device according to the present invention, Fig. 2 is a diagram configuring a three-dimensional stereoscopic image based on a tomographic image, and Fig. 3 is a diagram showing a three-dimensional stereoscopic image. Figure 4 is a diagram showing how to cut out the reprojected image in units of imperial palace layer and create the reprojected image. Figure 5 shows how to cut out the tomographic image in imperial palace layer units. FIG. 6, which is a diagram showing how stacked reprojection images are displayed continuously, shows reprojection images and tomographic images. DESCRIPTION OF SYMBOLS 1... Storage device, 2... Interpolation processing device, 3... Affine transformation device, 4... lJn subtraction device, 5... Coordinate input device, 6... Input means (keyboard) 7.・・・
Display device Figure 3

Claims (1)

[Claims] A storage device that stores tomographic images constructed by data collection or tomographic images constructed by interpolation based on these tomographic images, and affine transformation that performs affine transformation on each tomographic image in the desired direction to create a parallel projection image. an adding/subtracting device that is capable of adding the parallel projection images to create a reprojection image and adding or subtracting the parallel projection image to the reprojection image; and a display device that displays the reprojection image; An input means for specifying and inputting an arbitrary cross section of the re-projected image displayed on the display device is provided, and the adding/subtracting device performs addition and subtraction of the parallel projected image until the cross section specified by the input means is displayed. A three-dimensional display device.