OPTICAL COHERENCE TOMOGRAPHY-BASED INTRAORAL SCANNER CALIBRATION DEVICE AND METHOD FOR OBTAINING CALIBRATION INFORMATION THROUGH FULL AREA SCAN

Abstract

The present inventive concept relates to an optical coherence tomography (OCT)-based intraoral scanner calibration device including: a light source; an optical coupler for splitting the path of light irradiated from the light source in first light and second light; a reference part for generating reference light from the first light split by the optical coupler; a sample part for generating measurement light from the second light split by the optical coupler; and a signal generator for generating an OCT image from the reference light and the measurement light.

Claims

1. An optical coherence tomography (OCT)-based intraoral scanner calibration device comprising: a light source; an optical coupler for splitting the path of light irradiated from the light source in first light and second light; a reference part for generating reference light from the first light split by the optical coupler; a sample part for generating measurement light from the second light split by the optical coupler; and a signal generator for generating an OCT image from the reference light and the measurement light.

2. The device according to claim 1, wherein the sample part comprises a calibration tip mounted on a probe tip and having an image sensor.

3. The device according to claim 2, wherein the image sensor obtains pixel information on a full position area of a measurement object that corresponds to input voltages of an OCT intraoral scanner.

4. The device according to claim 3, wherein the obtained pixel information corresponds to the position values of the measurement object.

5. A method for obtaining calibrated information through full area scans using an optical coherence tomography (OCT)-based intraoral scanner by acquiring pixel information through the full area scans on an x-axis and a y-axis, by means of a calibration tip that is mounted a probe tip of the OCT-based intraoral scanner and has an image sensor, and by transforming position information compared to input voltages corresponding to the acquired pixel information into the input voltages compared to the position information, the method comprising the steps of: increasing a y-axis input voltage by one step voltage value from an initial value (Vy=Vmin); whenever the y-axis input voltage is increased by one step voltage value from the initial value, increasing an x-axis input voltage by one step voltage value from an initial value (Vx=Vmin) to store the position values of the image sensor generated until the x-axis input voltage is increased to a maximum input voltage; until the y-axis input voltage reaches the maximum voltage, repeatedly storing the position values of the x-axis full area voltages according to the y-axis input voltages; and transforming the stored position values of the x-axis full area voltages into the input voltages compared to the position information to thus obtain the calibrated voltage values according to the full area positions of the measurement object.

6. The method according to claim 5, after the step of obtaining the calibrated voltage values according to the full area positions, further comprising the steps of: generating voltage values to be inputted to micro-electromechanical systems (MEMS), based on the calibrated voltage values; generating a camera trigger signal at a position corresponding to the generated voltage inputs to the MEMS; inputting the voltage values to the MEMS; and outputting the camera trigger signal at the position corresponding to the voltage values inputted to the MEMS.

7. The method according to claim 5, after the step of obtaining the calibrated voltage values according to the full area positions, further comprising the steps of: generating a voltage waveform to operate the MEMS; inputting the generated voltage waveform to the MEMS; and if the voltage value inputted to the MEMS is the calibrated voltage value, inputting the trigger signal to a camera.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and other objects, features and advantages of the present inventive concept will be apparent from the following detailed description of the preferred embodiments of the invention in conjunction with the accompanying drawings, in which:

[0017] FIG. 1 is a concept view showing an OCT-based intraoral scanner on which a calibration tip is mounted, which is adopted in the present inventive concept;

[0018] FIG. 2 is a graph showing the pixel information acquired through the calibration tip that corresponds to position information;

[0019] FIG. 3 is a flowchart showing a process of obtaining calibrated input voltages through full area scans according to the present inventive concept;

[0020] FIG. 4 is a flowchart showing a method for capturing linearly calibrated intraoral scans with the use of calibrated input voltages as the input voltages of the OCT-based intraoral scanner; and

[0021] FIG. 5 is a flowchart showing another method for capturing linearly calibrated intraoral scans according to the present inventive concept.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Objects, characteristics and advantages of the present inventive concept will be more clearly understood from the detailed description as will be described below and the attached drawings. Before the present inventive concept is disclosed and described, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. An embodiment of the present inventive concept as will be discussed later will be in detail described so that it may be carried out easily by those having ordinary skill in the art, and therefore, this does not limit the idea and technical scope of the invention.

[0023] Hereinafter, the present inventive concept will be explained in detail with reference to the attached drawings.

[0024] FIG. 1 is a concept view showing an OCT-based intraoral scanner on which a calibration tip is mounted, which is adopted in the present inventive concept, and FIG. 2 is a graph showing the pixel information acquired through the calibration tip that corresponds to position information.

[0025] Referring to FIGS. 1 and 2, an OCT-based intraoral scanner calibration device according to the present inventive concept includes a light source, an optical coupler or beam splitter for splitting the path of light irradiated from the light source in first light and second light, a reference part for generating reference light from the first light split by the optical coupler or beam splitter, a sample part for generating measurement light from the second light split by the optical coupler or beam splitter, and a signal generator for generating an OCT image from the reference light and the measurement light.

[0026] The light source generates light, and the light generated from the light source is transmitted to the optical coupler or beam splitter through optical fibers. The light source emits light having a wavelength in a near-infrared region, but it is not limited necessarily thereto.

[0027] The optical coupler or beam splitter splits the path of the incident light through the optical fibers from the light source in the first light and the second light. The first light split through the optical coupler or beam splitter is inputted to the path of the reference light, and the second light to the path of the measurement light.

[0028] According to an embodiment of the present inventive concept, the first light emitted from the optical coupler is inputted to the reference part through the optical fibers disposed between the optical coupler and the reference part, and the second light to the sample part through the optical fibers disposed between the optical coupler and the sample part. The sample part has a probe tip mounted thereon to capture the teeth scan in the oral cavity.

[0029] The reference light is generated from the first light inputted to the reference part, and the measurement light from the second light inputted to the sample part. The reference light, which moves by a given path in the reference part and is reflected and outputted therefrom, is inputted again to the optical coupler through the optical fibers. The measurement light, which moves by a given path in the sample part, is reflected onto a measurement object, and is outputted therefrom, is inputted again to the optical coupler through the optical fibers.

[0030] The reference light and the measurement light, which are incident onto the optical coupler through the optical fibers from the reference part and the sample part, are inputted to the signal generator through the optical fibers.

[0031] The signal generator generates the OCT images for the measurement object from the combined reference light and measurement light.

[0032] According to the present inventive concept, in specific, the sample part has a calibration tip mounted on the probe tip and having an image sensor.

[0033] The image sensor of the calibration tip obtains pixel information corresponding to full area input voltages, as scanner input voltages. The pixel information corresponds to the position information of the measurement object.

[0034] As there is a given distance per one pixel, that is, the position information of the measurement object can be acquired from the pixel information obtained from the image sensor. According to the present inventive concept, therefore, the pixel information corresponding to the input voltages is the position information of the measurement object (See FIG. 2).

[0035] Further, the input voltages to the position information are transformed into the position information to input voltages to obtain the input voltages at the calibrated positions through full area scans (See FIG. 2).

[0036] FIG. 3 is a flowchart showing a process of obtaining calibrated input voltages through full area scans according to the present inventive concept.

[0037] Referring to FIG. 3, first, a y-axis input voltage is increased by one step voltage value from an initial value (Vy=Vmin).

[0038] In this case, whenever the y-axis input voltage is increased by one step voltage value from the initial value, an x-axis input voltage is increased by one step voltage value from an initial value (Vx=Vmin), and accordingly, the position values of the image sensor, which are generated until the x-axis input voltage is increased from a minimal input voltage to a maximum input voltage, are stored. This is because the pixel values measured by the image sensor correspond to the position values.

[0039] Next, the y-axis input voltage is increased again by one step voltage value, and in this case, the position values of the image sensor, which are generated until the x-axis input voltage is increased from a minimal input voltage to a maximum input voltage, are stored.

[0040] Until the y-axis input voltage reaches the maximum voltage, the position values of the x-axis full area voltages according to the y-axis input voltages are repeatedly stored.

[0041] Through the repetition, the position information for all of Vx and Vy can be obtained, and the position information is transformed into input voltages compared to the position information to thus obtain linear position calibration voltages on a region of interest (ROI), that is, voltage information calibrated according to the positions of the measurement object (See FIG. 2).

[0042] Further, it is possible to capture the oral scan calibrated through the linear position calibration voltages obtained by the above-mentioned method.

[0043] FIG. 4 is a flowchart showing a method for capturing the calibrated oral scan according to the present inventive concept.

[0044] Referring to FIG. 4, voltage values (Vx and Vy values) to be inputted to micro-electromechanical systems (MEMS) are generated based on the calibrated voltage values.

[0045] A camera trigger signal is generated at a position corresponding to the generated voltage inputs to the MEMS.

[0046] Next, the voltage values are inputted to the MEMS, and the camera trigger signal is outputted at the position corresponding to the voltage values inputted to the MEMS.

[0047] Through the above-mentioned process, the calibrated input voltages are used as the input voltages of the OCT-based intraoral scanner, thereby making it possible to capture the linearly calibrated oral scan.

[0048] FIG. 5 is a flowchart showing another method for capturing linearly calibrated intraoral scans according to the present inventive concept.

[0049] Referring to FIG. 5, first, a voltage waveform is generated to operate the MEMS, and next, the generated voltage waveform is inputted to the MEMS. In this case, if the voltage value inputted to the MEMS is the calibrated voltage value, the trigger signal is inputted to a camera.

[0050] Accordingly, a voltage of a sine wave or sawtooth wave is used as an input voltage for the OCT scanner, and if a current voltage corresponds to the calibrated input voltage, the trigger signal is generated to allow the camera to capture the linearly calibrated oral scan.

[0051] As set forth in the foregoing, the present inventive concept allows the pixel information of the image sensor to correspond to the position information, is intuitive so that calibration is easily performed, and replaces the input signal with the calibrated signal so that the calibration result can be conveniently checked.

[0052] The foregoing description of the embodiments of the invention has been presented for the purpose of illustration; it is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Persons skilled in the relevant art can appreciate that many modifications and variations are possible in light of the above teachings. It is therefore intended that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto.