KR102470764B1 - How to scan the mouth and face using an optical lens for an oral scanner - Google Patents

Abstract

The present invention secures a wide angle of view of the imaging lens of the oral scanner without a face scanner or a digital camera, enabling quick face scan, using an optical lens for an oral scanner for performing aesthetic design of teeth through the face scan and oral scan. It relates to a method of scanning the oral cavity and scanning the face, comprising: performing an oral scan to obtain oral scan data; removing or replacing a tip after obtaining the oral scan data; and converting to a face scan by performing a face scan. The method may include obtaining data and collecting the acquired oral cavity scan data and face scan data.

Description

How to scan the mouth and face using an optical lens for an oral scanner}

The present invention relates to a method for oral scan and face scan using an optical lens for an intraoral scanner, and more particularly, fast face scan is possible by securing a wide angle of view of an imaging lens of an intraoral scanner without a face scanner or a digital camera, It relates to a method of performing an oral scan and a face scan using an optical lens for an oral scanner for performing aesthetic design of teeth by combining the face scan and oral scan.

The imaging lens used in the existing triangulation method is set at an angle of view sufficient to scan the size of a molar (molar tooth), and has a narrow angle of view as shown in FIG. .

Therefore, since it takes a long time to perform a face scan using only an intraoral scanner and data is inaccurate, it is inconvenient to photograph a face using a face scanner or a digital camera. Regarding this, reference may be made to Korean Registered Patent No. 10-1744079-0000 (2017.05.31).

In addition, the triangulation method (refer to Korean Registered Patent No. 10-2129915-0000 (2020.06.29)) that obtains surface data using triangulation when a light source is reflected from an impression body or plaster model and reaches the optical sensor has the best angle of view of the imaging lens. Since only large molars, i.e. molars, were scanned, there was a problem that the angle of view was narrow, and the area of the face had to be scanned and attached by the size of the molars.

Therefore, it takes a long time to scan a face only with an intraoral scanner having a narrow angle of view and inaccurate data are generated.

An object of the present invention for solving the above problems is to scan the oral cavity and face using an optical lens for an oral scanner that secures a wide angle of view of the imaging lens of the oral scanner without a face scanner or a digital camera to enable fast face scanning. in providing a way.

The present invention for achieving the above object is a light output unit for outputting a light source, two or more mirrors for reflecting the light output from the light output unit to left and right or upper and lower teeth, disposed on the left and right sides of the light output unit to prevent the mirror from An oral scan and a face scan method using an optical lens for an oral and facial scanner including two or more image sensors for photographing reflected teeth and an imaging lens located at the front end of the sensor to widen the angle of view, Acquiring intraoral scan data by performing oral scan, removing the tip and converting to face scan after acquiring the oral scan data, performing face scan to acquire face scan data, the acquired oral scan data and face It may include collecting scan data.

Also, the light output unit is DLP (Digital Light Processing), and the projection lens may be a DLP projection lens.

In addition, the face scan may be performed in a stereo vision manner after removing the tip of the intraoral scanner.

In addition, a step of calibrating before the intraoral scan may be further included.

In addition, the angle of view of the imaging lens,

h' = f x tanθ (h': sensor size, f: focal length, θ: angle of view)

expression can be satisfied.

를 만족하고, 화각의 범위는

를 만족할 수 있다.In addition, the focal length range of the imaging lens is

is satisfied, and the range of angle of view is

can be satisfied.

On the other hand, the present invention is a light output unit for outputting a light source, two or more mirrors for reflecting the light output from the light output unit to the left and right or upper and lower teeth, disposed on the left and right of the light output unit to photograph the teeth reflected from the mirrors It relates to a method for oral scan and face scan using an optical lens for scanning the oral cavity and face including two or more image sensors located at the front end of the sensor and an imaging lens for widening the angle of view, which performs oral scan Acquiring oral scan data, replacing the tip and switching to a face scan after acquiring the oral scan data, performing a face scan to obtain face scan data, collecting the acquired oral scan data and face scan data steps may be included.

Also, the replacement tip may be a (-) power lens tip.

In addition, the face scan may be performed in a structured light manner after replacing the tip of the intraoral scanner.

In addition, a step of calibrating before the intraoral scan may be further included.

In addition, the angle of view of the imaging lens,

h' = f x tanθ (h': sensor size, f: focal length, θ: angle of view)

expression can be satisfied.

를 만족하고, 화각의 범위는

를 만족할 수 있다.In addition, the focal length range of the imaging lens is

is satisfied, and the range of angle of view is

can be satisfied.

Also, the light output unit is DLP (Digital Light Processing), and the projection lens may be a DLP projection lens.

The present invention has the advantage of securing a wide angle of view of the imaging lens of the intraoral scanner, enabling rapid face scanning, and obtaining accurate face scan data by removing or replacing the tip.

1 is a graph showing the angle of view for each focal length according to the method of oral scan and face scan using the optical lens for intraoral scanner of the present invention;
Figure 2 is a configuration diagram showing the configuration of the scanner when the tip of the oral scanner according to an embodiment of the present invention is removed;
3 is a flow chart showing a method for obtaining a face scan when removing the tip of an oral scanner according to an embodiment of the present invention;
Figure 4 is a configuration diagram showing the configuration of the scanner when replacing the tip of the intraoral scanner according to another embodiment of the present invention;
5 is a flowchart illustrating a method for securing a face scan when replacing a tip of an intraoral scanner according to an embodiment of the present invention.

Since the present invention can apply various transformations and have various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the detailed description. Effects and features of the present invention, and a method of achieving them will become clear with reference to the embodiments described later in detail together with the drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various forms. In the following embodiments, terms such as first and second are used for the purpose of distinguishing one component from another component without limiting meaning. Also, expressions in the singular number include plural expressions unless the context clearly dictates otherwise. In addition, terms such as include or have mean that features or elements described in the specification exist, and do not preclude the possibility that one or more other features or elements may be added. In addition, in the drawings, the size of components may be exaggerated or reduced for convenience of description. For example, since the size and thickness of each component shown in the drawings are arbitrarily shown for convenience of description, the present invention is not necessarily limited to the illustrated bar.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 is a graph showing the angle of view for each focal length according to the oral scan and face scan method using the optical lens for intraoral scanner of the present invention, Figure 2 is a case where the tip of the intraoral scanner according to an embodiment of the present invention is removed Figure 3 is a block diagram showing the configuration of a scanner, Figure 3 is a flow chart showing a face scan securing method in case of removing the tip of the oral scanner according to an embodiment of the present invention, Figure 4 is for oral according to another embodiment of the present invention A configuration diagram showing a configuration of a scanner when a tip of a scanner is replaced, and FIG. 5 is a flowchart illustrating a method for securing a face scan when a tip of an intraoral scanner is replaced according to an embodiment of the present invention. See Figures 1 to 5.

The present invention is to secure a wide angle of view of an imaging lens of an intraoral scanner without a face scanner or a digital camera to enable fast face scan.

To this end, the present invention provides a light output unit for outputting a light source, two or more mirrors for reflecting the light output from the light output unit and reflected from the measurement object to an image sensor, disposed on the left and right sides of the light output unit and reflected from the mirrors. It may include an optical lens for an oral scanner that scans the mouth and face using an oral scanner including two or more image sensors for photographing teeth and an imaging lens located at the front end of the sensor to widen the angle of view. In addition, a projection lens may be included in front of the light output unit.

The light source may be a DLP (Digital Light Processing) projector pattern, and left and right cameras centered on the light source may be cameras that measure in a stereo vision method. The projection lens may be a DLP projection lens.

An aspect of the present invention is to provide a method for widening an angle of view during face scanning.

In the case of face scanning, the tip of the intraoral scanner can be removed to perform a face scan in a stereo vision method, or the tip of the intraoral scanner can be replaced with a lens of (-) power to perform a face scan in a structured light method.

In particular, the present invention presents the most desirable optical conditions for widening the angle of view.

Hereinafter, the range of the angle of view is calculated as follows.

In order to obtain the angle of view of an imaging lens, the magnification of the lens must be obtained.

Magnification m is the same as equation (1). (h: molar tooth measurement range, h': sensor size)

m = h/h' ...(1)

In addition, if the magnification is expressed in terms of the object distance s and the image distance s' of the imaging lens,

Magnification m is the same as Equation (2).

m = s'/s ...(2)

The image distance s' can be obtained with the object distance s and magnification m suitable for driving the hand piece of the intraoral scanner, and the focal length f can be obtained from the s'.

1/s - 1/s' = 1/f...(3)

The angle of view (θ) is obtained from the focal length (f) and the sensor size (h') of the imaging lens as shown in Equation (4).

h' = f x tanθ...(4)

Therefore, the size of the angle of view for each focal length is the same as in FIG. 1 .

That is, as the size of the sensor increases, the angle of view increases, and as the focal length decreases, the angle of view increases.

를 만족하고, 화각의 범위는

를 만족해야 한다.Therefore, the focal length range of a preferred imaging lens for increasing the angle of view is

is satisfied, and the range of angle of view is

should satisfy

tip removal type

In one embodiment of the present invention, the tip removal type is to perform a face scan in a stereo vision method by removing the tip after the intraoral scan.

Referring to FIGS. 2 and 3 , the tip removal type according to an embodiment of the present invention performs calibration before intraoral scanning. Thereafter, an intraoral scan is performed, and the tip of the intraoral scanner is removed after the intraoral scan is completed. After removing the tip, a face scan is performed in a stereo vision method, and an accurate tooth shape may be modeled by collecting the oral scan data and the face scan data.

Preferred optical system conditions for face scan in this embodiment may be as follows.

- Focal length f : 17mm

- Sensor size h' : 10mm

- Angle of view θ : 30.46 deg

- Object distance s : 120mm

- Measuring range h : 64mm

That is, the focal length f of the optical system may be smaller than or equal to 17 mm, and the sensor size h' may also be smaller than 10 mm.

tip replacement type

In another embodiment of the present invention, in order to obtain accurate data during face scanning, the tip of the intraoral scanner can be replaced and a face scan can be performed using a structured light method using a lens of negative power in front of the projection lens.

4 and 5, the replacement tip is mounted in front of a DLP (Digital Light Processing) projection lens so as to connect a lens of (-) power, and irradiation in DLP (Digital Light Processing) due to the replacement tip. The area of the pattern to be is expanded and becomes larger. Accordingly, the enlarged pattern area may be captured by an imaging lens.

That is, the face scan in this embodiment is performed by the structured light method after replacing the tip of the intraoral scanner.

Referring to FIG. 2 , calibration is performed before intraoral scan. Thereafter, an intraoral scan is performed, and the tip is replaced after the intraoral scan is completed. The replacement tip may be a (-) power lens, and then a face scan is performed with the replaced (-) power lens. In this way, the angle of view of the face scan can be widened.

Finally, by combining the oral scan data and the face scan data, an accurate tooth shape may be modeled.

As described above, the embodiments according to the present invention have been reviewed, and the fact that the present invention can be embodied in other specific forms in addition to the above-described embodiments without departing from the spirit or scope is those skilled in the art. It is self-evident to Therefore, the foregoing embodiments should be regarded as illustrative rather than restrictive, and thus the present invention is not limited to the foregoing description and may be modified within the scope of the appended claims and their equivalents.

Claims (13)

A light output unit for outputting a light source, two or more mirrors for reflecting light output from the light output unit and reflected from the measurement object to an image sensor, and two or more mirrors disposed on the left and right sides of the light output unit for photographing the teeth reflected from the mirrors. It relates to a method of oral scan and face scan using an optical lens for oral and facial scanners including at least one image sensor and an imaging lens located at the front end of the sensor to widen the angle of view,
Obtaining oral scan data by conducting an intraoral scan;
After acquiring the intraoral scan data, removing the tip and switching to a face scan;
obtaining face scan data by performing a face scan;
A method of performing oral scan and face scan using an optical lens for an oral scanner comprising the step of collecting the acquired oral scan data and face scan data. According to claim 1,
The light output unit is a DLP (Digital Light Processing) projector pattern, and the projection lens is a method of oral scan and face scan using an optical lens for an oral scanner, characterized in that the DLP projection lens. According to claim 1,
The face scan method of oral scan and face scan using an optical lens for an oral scanner, characterized in that the stereo vision method after removing the tip of the oral scanner. According to claim 1,
A method of performing an oral scan and a face scan using an optical lens for an oral scanner, further comprising the step of calibrating before the oral scan. According to claim 1,
The angle of view of the imaging lens is
h' = fx tanθ (h': sensor size, f: focal length, θ: angle of view)
A method of oral scan and face scan using an optical lens for an intraoral scanner, characterized in that it satisfies the equation. According to claim 5,
The focal length range of the imaging lens is

Satisfies, and the field of view range of the imaging lens is

Oral scan and face scan method using an optical lens for an intraoral scanner, characterized in that satisfies the. A light output unit for outputting a light source, two or more mirrors for reflecting light output from the light output unit and reflected from the measurement object to an image sensor, and two or more mirrors disposed on the left and right sides of the light output unit for photographing the teeth reflected from the mirrors. It relates to a method of oral scan and face scan using an optical lens for oral and facial scanners including at least one image sensor and an imaging lens located at the front end of the sensor to widen the angle of view,
obtaining oral scan data by conducting an intraoral scan;
After acquiring the intraoral scan data, switching to tip replacement and face scan;
obtaining face scan data by performing a face scan;
A method of performing oral scan and face scan using an optical lens for an oral scanner comprising the step of collecting the acquired oral scan data and face scan data. According to claim 7,
The replacement tip is a method of oral scan and face scan using an optical lens for an oral scanner, characterized in that the (-) power lens tip. According to claim 7,
The face scan is a method of oral scan and face scan using an optical lens for an oral scanner, characterized in that the structured light method is performed after replacing the tip of the oral scanner. According to claim 7,
A method of performing an oral scan and a face scan using an optical lens for an oral scanner, further comprising the step of calibrating before the oral scan. According to claim 7,
The angle of view of the imaging lens is
h' = fx tanθ (h': sensor size, f: focal length, θ: angle of view)
A method of oral scan and face scan using an optical lens for an intraoral scanner, characterized in that it satisfies the equation. According to claim 11,
The focal length range of the imaging lens is

Satisfies, and the field of view range of the imaging lens is

Oral scan and face scan method using an optical lens for an intraoral scanner, characterized in that satisfies the. According to claim 7,
The light output unit is a DLP (Digital Light Processing) projector pattern, and the projection lens is a method of oral scan and face scan using an optical lens for an oral scanner, characterized in that the DLP projection lens.

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