JP2675500B2 - Light spot tracking device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light spot tracking device capable of tracking the movement of a light spot.

[0002]

2. Description of the Related Art Conventionally, as a technique for tracking the movement of a light spot, a photoconductive cell in which a resistor film is formed on one surface of a light-receiving film and a conductive film is formed on the other surface of the light-receiving film where the light-transmitted portion becomes conductive is used. ,
There is known a technique of tracking the light spot by measuring the position where the light spot hits from the resistance value in the vertical direction and the resistance value in the horizontal direction.

[0003]

However, in this technique, when there are a plurality of light spots, or when light other than the light spots is incident even if the light is weaker than the light spots, the output resistance is reduced. Since the value is affected by light other than the light spot to track,
It had a problem that it could not measure and trace the light spot.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a light spot tracking device capable of tracing a target light spot even if there are a plurality of light spots or light weaker than the light spots is present in the surroundings. In offer.

[0005]

The light spot tracking device of the present invention comprises: a) a camera provided with a large number of pixels for measuring the light intensity, and b) a camera for taking an image of a light spot moved by the plurality of pixels. And forming a moving block that moves in the image receptor composed of the measured light by the large number of pixels, and is composed of an aggregate of a plurality of pixels divided into three or more by contacting the moving block at one place. Block forming means for forming divided blocks, light intensity comparing means for comparing the light intensities of the respective divided blocks based on the pixels of which light intensity exceeding a reference value is measured among a plurality of pixels in each divided block, And an electric circuit including block moving means for moving the moving block so that the contact point of each divided block is located at the light spot based on the comparison result of the intensity comparing means. It adopted the operative means.

[0006]

The light spot is photographed by a camera having a large number of pixels for measuring the light intensity. Initially, the light spot to be traced is set in the moving block formed by the block forming means.
The initial setting of the light spots can be applied in various ways, such as by reading the distribution state of the light intensity in the image receptor imaged by the camera and designating it, even if it is performed on the display using a mouse or the like. If you set the light spot to track in the moving block,
The comparing means compares the light intensities of the respective divided blocks based on the pixels whose light intensity exceeds the reference value in each divided block, and based on the comparison result, the point where the block moving means contacts the respective divided blocks is the light spot. Move the moving block so that it is located at. As a result, the light spot having a high light intensity converges on the position where each divided block contacts. When the light spot moves, the number of pixels whose light intensity exceeds the reference value is measured in the divided block on the side where the light spot moves, or the sum of the light intensities increases. That is, when the light spot moves, the light intensity ratio of each divided block compared by the comparison means changes. However, the block moving means moves the moving block so that the contact point of each divided block is located at the light spot based on the comparison result of the comparing means. It converges on the contact point of the divided blocks, and as a result, the contact point of each divided block traces the light spot.

[0007]

As described above, in the light spot tracking device of the present invention, since the moving block in the image receiver tracks one light spot, another light spot is recorded in the image receiver of the camera. The target light spot can be tracked even if there is a light spot or if light weaker than the light spot is present in the image receptor. Further, by tracing the light spot, it is possible to measure the locus of the light spot or the movement locus of the object to which the light spot is attached.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the light spot tracking device of the present invention will be described with reference to the drawings based on an embodiment in which it is applied to a manufacturing device for a prosthetic restoration for a crown. [Structure of Embodiment] FIGS. 1 to 5 show an embodiment of the present invention. FIG. 1 is a schematic block diagram of an apparatus for manufacturing a prosthesis for restoration of a crown, and FIG. 2 is a handpiece used for treatment of teeth. FIG. 3 is a perspective view of a tooth to be treated. The manufacturing apparatus 1 for a prosthetic restoration for crowns measures the trajectory of the cutting element 3 by capturing the movement of the handpiece 2 and the movement of the tooth 4 to be cut by the cutting element 3, and cuts from the difference. The shape cut by the child 3 is measured. Then, a filling material for restoration of the crown corresponding to the measured cutting shape is prepared by using CAM.

In order to measure the three-dimensional movement of the handpiece 2, first to third light spots 5 to 7 are provided at each end of the triangular plate 2a attached to the handpiece 2. The first to third light spots 5 to 7 are very small in size and emit light of high intensity at the ends of the light emitting diode or the optical fiber. Further, two first and second CCD cameras 8 and 9 are installed at positions where the range of movement of the first to third light spots 5 to 7 provided on the handpiece 2 can be imaged.

On the other hand, the tooth 4 cut by the cutting element 3
In order to measure the three-dimensional movement of the
As shown in FIG.
The tooth mounting member 14 provided with the light spots 11 to 13 is mounted. The fourth to sixth light spots 11 to 13 are also very small in size at the ends of the light emitting diode and the optical fiber,
And emits high intensity light. Further, the third and fourth CCD cameras 15 and 16 are installed so as to capture the range in which the fourth to sixth light spots 11 to 13 provided on the tooth mounting member 14 move.

First CCD camera 8, second CCD camera 9, third CCD camera 15, and fourth CCD camera 1
6, the first to third light spots 5 to 7 of the handpiece 2 and the fourth to sixth light spots 11 of the tooth mounting member 14.
The movements of 13 to 13 are analyzed by the electric circuit 17 using a computer. The computer function of the electric circuit 17 includes
A function is provided for tracking each light spot captured by each camera. The light spot tracking function includes a first light spot tracking function 18 for tracking the first light spot 5 captured by the first CCD camera 8 and a first CC.
The second light spot tracking function 19 for tracking the second light spot 6 captured by the D camera 8, the third light spot tracking function 20 for tracking the third light spot 7 captured by the first CCD camera 8, and the second light spot capturing function of the second CCD camera 9 Fourth light spot tracking function 21 for tracking one light spot 5, second CCD
A fifth light spot tracking function 22 for tracking the second light spot 6 captured by the camera 9, a sixth light spot tracking function 23 for tracking the third light spot 7 captured by the second CCD camera 9, and a fourth light spot captured by the third CCD camera 15. Seventh light spot tracking function 24 for tracking the light spot 11, the third CC
An eighth light spot tracking function 25 for tracking the fifth light spot 12 captured by the D camera 15, and a sixth light spot 13 captured by the third CCD camera 15
Ninth light spot tracking function 26 for tracking light, fourth CCD camera 1
Tenth light spot tracking function 2 for tracing the fourth light spot 11 imaged by 6
7. An eleventh light spot tracking function 28 for tracking the fifth light spot 12 captured by the fourth CCD camera 16 and a twelfth light spot tracking function 29 for tracking the sixth light spot 13 captured by the fourth CCD camera 16.

The first light spot tracking function 18 is provided with a block forming means 31 for forming a moving block 30 for moving the first light spot 5 captured by the first CCD camera 8 while tracking it. The moving block 30 is shown in FIG.
~ It is divided into fourth divided blocks 32 to 35. The first to fourth divided blocks 32 to 35 are CCDs, respectively.
In this embodiment, the divided blocks adjacent to each other are formed by one pixel of 10 pixels × 10 pixels of the camera.
Reference numeral 36 in the figure is a central dot that is in contact with each divided block and is common to each block.

In addition, the first light spot tracking function 18 includes
Based on the light intensity comparing means 37 for comparing the light intensity of each of the fourth divided blocks 32 to 35 and the comparison result of the light intensity comparing means 37, the central dot 36 is positioned at the center of the first light spot 5 and A block moving means 38 is provided to move the moving block 30 so that the fourth divided blocks 32 to 35 have the same light intensity. Light intensity comparison means 37 of this embodiment
First, in each of the first to fourth divided blocks 32 to 35, as shown in FIG. 5, the light intensity of unnecessary light below a predetermined reference is not measured, but only the light intensity of a pixel that clears the reference value is measured. The sum of the light intensities in the first divided block 32 is measured, the sum of the light intensities in the second divided block 33 is b, the sum of the light intensities in the third divided block 34 is c, and the fourth divided block 35 is measured. Let d be the sum of the light intensities. Next, compare each light intensity,
The moving direction and the moving amount of the moving block 30 are calculated.
The movement amount (moving pixel number) m of the moving block 30 in the X direction (for example, the lateral direction of the image receptor imaged by the monitor device) is calculated by the following equation.

## EQU1 ## Xm = {(b + d)-(a + c)} k / allV The movement amount (the number of moving pixels) n of the moving block 30 in the Y direction (for example, the vertical direction of the image receptor imaged by the monitor device) is It is calculated by the formula.

## EQU00002 ## Yn = {(c + d)-(a + b)} k / allV where k is the moving speed coefficient of the moving block 30, al.
LV is a + b + c + d. Then, the block moving means 38 moves the moving block 30 based on the moving amount obtained by the above [Equation 1] and [Equation 2]. by this,
So that the central dot 36 is located at the center of the first light spot 5,
The moving block 30 moves. That is, the central dot 36
Always converges on the first light spot 5, and as a result, the central dot 36 tracks the movement of the first light spot 5. In other words, by measuring the movement of the central dot 36 with a computer,
The movement of the first light spot 5 can be tracked.

The second to twelfth light spot tracking functions 19 to 2
9 is different from the first light spot tracking function 18 only in the light spots to be followed and is otherwise provided in the same manner, and therefore the respective configurations are omitted.

The computer of the electric circuit 17 has the first to third light spots 5 tracked by the first to third light spot tracking functions 18 to 20.
7 to 7, and fourth to sixth light spot tracking functions 21 to 2
The cutting element locus calculation means 3 for measuring the three-dimensional movement of the cutting element 3 from the respective loci of the first to third light spots 5 to 7 tracked by No. 3 of FIG.
9 is provided. In addition, the computer of the electric circuit 17 has the fourth to sixth positions tracked by the seventh to ninth light spot tracking functions 24 to 26.
Each locus of the light spots 11 to 13 and the fourth to sixth light spots 11 to 13 tracked by the tenth to twelfth light spot tracking functions 27 to 29.
The tooth-to-be-cut trajectory calculating means 40 is provided for measuring the three-dimensional movement of the tooth 4 from each trajectory. Furthermore, the electric circuit 17
Of the computer, the three-dimensional movement of the cutting element 3 measured by the cutting element locus calculation means 39 and the cutting tooth locus calculation means 4 are calculated.
A cutting shape calculation means 41 for calculating and measuring the shape to be cut by the cutting element 3 from the difference between the measured three-dimensional movement of the tooth 4 and zero. Then, the measurement result is stored in the internal storage device.

The electric circuit 17 is provided with a reversing output means 42 for reversing and outputting the shape cut by the cutting element 3 measured by the cutting shape calculating means 41. The reversing output means 42 operates the three-dimensional cutting machine 43. By doing so, a prosthetic restoration for a crown that matches the cut shape can be manufactured.

[Effect of Embodiment] In this embodiment, as described above, even if one CCD camera measures three light spots, each light spot can be traced. Also,
Even when there is light other than the light spot, such as the handpiece 2 of the dentist or the oral cavity of the patient, the light spot can be traced without being affected by other light. Further, since the divided blocks 32 to 35 are provided so as to overlap each other,
Even if a light spot exists between pixels, it is possible to stably converge the contact points of the divided blocks to the light spot.

[Modification] In the above embodiment, an example in which the moving speed of the moving block is set constant is shown. However, for example, when the light spot is far from the contact point of the divided blocks, the moving speed is increased. The moving speed may be set in two or more steps so that the moving speed is slowed down when the light spot approaches the contact point of the divided block.
The distance between the light spot and the contact point of the divided block can be determined from the ratio of the light intensity of each divided block, or an area can be provided in the moving block to determine whether the light spot exists in that area. Various applications such as judgment are possible. Although a CCD camera is illustrated as an example of the camera, a MOS camera using a MOS as an image receiving device may be used. Moving block size (divided block size)
Is set according to the changing speed of the light spot and the processing speed of the computer used, and is not limited to the shape and the number of pixels of this embodiment. That is, when the changing speed of the light spot is fast in the horizontal direction, various changes can be made such as a moving block that is long in the horizontal direction. The camera itself may be driven using an actuator so that the light spot is within the range in which the camera is imaged (for example, the moving block is located at the center of the image receiving body). The present invention has been applied to the field of dentistry, but the present invention can be applied to all devices that measure the moving position of light with a camera. As an example thereof, various applications such as shape measurement, movement trajectory measurement and movement speed measurement of a light emitting object (for example, a flying object, a light emitting body attached to a human body, etc.) are applicable. As the shape measurement, a light spot is projected onto an object to be measured using a laser device or the like, and the light spot is tracked by the present invention, and the light spot is constantly measured from the light intensity of the light spot by using a triangulation method. Calculate the distance of. The shape of the object to be measured can be measured from the changing state of the distance of the light spot and the speed and interval of the light spot. The shape of the object to be measured can be measured by using a plurality of light spots.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of a device for manufacturing a prosthetic restoration for a crown.

FIG. 2 is a perspective view of a handpiece used for treating teeth.

FIG. 3 is a perspective view of a tooth to be treated.

FIG. 4 is an explanatory diagram of a moving block.

FIG. 5 is a light intensity distribution graph for explaining the light intensity read by an electric circuit.

[Explanation of symbols]

 8 First CCD Camera 9 Second CCD Camera 15 Third CCD Camera 16 Fourth CCD Camera 17 Electric Circuit 30 Moving Block 31 Block Forming Means 32 First Divided Block 33 Second Divided Block 34 Third Divided Block 35 Fourth Divided Block 37 Light Intensity Comparison Means 38 Block moving means

Claims (1)

(57) [Claims] 1. A plurality of pixels for measuring light intensity are provided,
A camera that captures a moving light spot by the large number of pixels; and (b) (b-1) the large number of pixels captured by the camera.
Forming a moving block that moves in an image receptor formed by the light measured by
It 's an aggregate of multiple pixels that touch each other and are divided into three or more .
Block forming means for forming a Li Cheng divided blocks, a plurality of pixels in the (b-2) in each of the divided blocks
Then, a light intensity comparing means for comparing the light intensities of the respective divided blocks based on the pixels whose light intensity exceeding the reference value is measured , (b-3) From the comparison result of the light intensity comparing means, the respective divided blocks are in contact with each other. A light spot tracking device, comprising: an electric circuit having block moving means for moving the moving block so that a location is located at a light spot.