KR20120114756A - Spectral domain optical coherence tomograpy including of high resolution spectromiter and the method - Google Patents

Abstract

PURPOSE: An optical coherence tomography system including a high resolution spectroscope and a method thereof are provided to improve the quality of a final output image by obtaining accurate information about a pixel to wavelength region. CONSTITUTION: An optical coupler(120) divides light from a light source into reference light and measurement light and outputs the reference light and the measurement light to each light path. A reference unit(130) outputs the reflected reference light to the optical coupler. A sample unit(140) outputs the reflected measurement light to the optical coupler. A spectroscope(150) detects pixel and wavelength information by inputting and reflecting the synthesized light of the reference light and the measurement light according to the movement of a mirror. An image processing unit generates an image by processing the pixel information and the wavelength information. [Reference numerals] (110) Optical source; (120) Optical coupler; (130) Reference unit; (140) Sample unit; (150) Spectroscope

Description

Optical tomography system with high resolution spectroscopy and its method {SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPY INCLUDING OF HIGH RESOLUTION SPECTROMITER AND THE METHOD}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical tomography system and method thereof having a high-resolution spectrometer, and in particular, to obtain an accurate information on a pixel-to-wavelength region in an optical tomography system using a spectrometer, the quality of a final output image can be improved. An optical tomography system having a high resolution spectrometer and a method thereof.

Recently, the development of an optical coherence tomography apparatus (OCT), which has a simpler structure than a computed tomography machine or a magnetic resonance imaging machine and which can provide a higher resolution than an ultrasonic imaging machine, has been developed.

BACKGROUND OF THE INVENTION An optical coherence single photographing apparatus is a device that obtains a tomographic image of a living body by irradiating low coherence light close to natural light to a multi-scattering material such as a living body and detecting light reflected from the material.

Such conventional optical tomography apparatuses are characterized and manufactured according to samples corresponding to respective wavelength characteristics, and tomography is performed using different systems on the same sample.

In other words, SD-OCT with a central wavelength of 840 ㎚ is absorbed by substances such as water, and is widely applied to diagnosis of diseases in the central fovea of the eye. Due to the long wavelength range, it is widely applied to disease diagnosis of blood vessel tissue.

The optical tomography apparatus analyzes the performance of the optical system by obtaining information on the pixel-to-wavelength region by inserting or separately adding a spectroscope to the system in order to accurately obtain the final tomographic image.

However, there is a risk of measurement error in spectroscopic performance analysis due to the addition of new devices, and there is a limit that the performance must be analyzed again after modification if it is not the desired specification.

The technical problem to be solved by the present invention is an optical tomography having a high-resolution spectrometer that can improve the quality of the final output image by obtaining accurate information about the pixel-to-wavelength region by moving the mirror in the optical biotomography system using a spectroscope A photographing system and a method thereof are provided.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, unless further departing from the spirit and scope of the invention as defined by the appended claims. It will be possible.

An optical tomography system having a high-resolution spectrometer according to the present invention for solving the above technical problem, the optical coupler for dividing the light emitted from the light source into a reference light and a measurement light and outputs to each light path; A reference unit which receives the reference light output from the optical coupler and outputs the reference light reflected through the reflection path back to the optical coupler, and receives the measurement light output from the optical coupler and radiates the reflected measurement light reflected on the subject A sample unit for outputting to the optical coupler, a spectrometer for receiving the synthesized light of the reference light and the measurement light from the optical coupler, a spectroscope for detecting pixel information and wavelength information using a mirror, and an electrical signal output from the spectroscope And an image processor configured to generate an image, wherein the spectroscope measures the movement displacement and the movement direction of the mirror. It is characterized in that the pixel intensity array and the wavelength array are obtained by setting and moving and obtaining the pixel intensity array and the wavelength array by the incident and reflection of the synthesized light at the position of the moved mirror.

The spectrometer may include a collimator for receiving the synthesized beam and converting the parallel beam into parallel light, a diffraction grating portion for receiving the parallel light converted by the collimator and separating the light into respective wavelength bands, and the angles separated from the diffraction grating portion. A focusing lens for condensing light, a line scan camera for receiving each light passing through the focusing lens and converting the light into an electrical signal, and a line scan camera provided between the focusing lens and the line scan camera and moving in a set direction to scan the line. It is characterized in that it comprises a mirror for reflecting the light input to the pixel of the camera according to the moving position, and a mirror driving unit for moving the mirror in a set direction.

Here, it is characterized in that it further comprises a mirror drive unit for mounting the mirror to move in the set direction.

Here, the mirror driving unit is characterized in that it has a structure that is transferred using a motor, a rail or the like.

Here, the mirror is characterized in that it is moved in the unit of μm or less.

The reference unit may include a collimator for converting light output from the optical coupler into parallel light; A lens for condensing parallel light output from the collimator; It is characterized in that it comprises a mirror for reflecting the light collected from the lens.

Here, the sample unit and a collimator for converting the light output from the optical coupler to parallel light; A scanner which scans the X-axis direction and the Y-axis direction of the subject by adjusting the parallel light output from the collimator in the radial direction; The scanner is characterized in that it comprises a scan lens for condensing the light whose radiation direction is adjusted to the subject.

According to a preferred embodiment of the present invention, an optical tomography method having a high-resolution spectrometer includes: dividing light emitted from a light source into reference light and measurement light and outputting the light into respective light traveling paths; Receiving the reference light again to receive the reference light reflected through a reflection path, receiving the measurement light, radiating the reflected light to a subject, and inputting and combining the measured light to output composite light; Injecting or reflecting the synthesized light into a camera pixel according to a position of a mirror to be moved, and detecting light incident on the camera pixel to obtain each pixel information and wavelength information corresponding to each pixel; And controlling the optical system to focus on each unit pixel by using the acquired pixel information and the wavelength information.

The acquiring of the pixel information and the wavelength information corresponding to each pixel may include setting a movement displacement and a movement direction of the mirror; Obtaining first pixel intensity array information and first wavelength array information for the current position of the mirror; Moving the mirror in which the movement direction is set; Obtaining second pixel intensity array information and second wavelength array information for a location after the mirror is moved; The predetermined pixel information value is obtained by calculating the first pixel intensity array information value and the second pixel intensity array information value, and the wavelength information value is calculated by calculating the first wavelength array information value and the second wavelength array information value. Its feature is that it includes the step of acquiring.

The second pixel intensity array information value may be calculated from a first pixel intensity array information value when the moving displacement of the mirror is in the + direction in the obtaining of the predetermined pixel information value and the wavelength information value. The characteristic is that the first wavelength array information value is calculated from the array information value.

Herein, in the obtaining of the predetermined pixel information value and the wavelength information value, when the displacement of the mirror is in the − direction, the first pixel intensity array information value is calculated from a second pixel intensity array information value, and the first wavelength is calculated. The characteristic is that the second wavelength array information value is calculated from the array information value.

Here, in the calculating process, the mirror is continuously moved with + or − displacement to calculate until the first pixel intensity array information value and the second pixel intensity array information value are the same, and the second wavelength array information value The characteristic is that it calculates until and the first wavelength array information value are equal.

Here, in the step of moving the mirror is characterized in that the mirror is moved to the unit of μm or less.

According to the present invention, an optical tomography system having a high-resolution spectrometer and a method thereof can improve the quality of a final output image by obtaining accurate information about a pixel-to-wavelength region by moving a mirror in an optical tomography system using a spectrometer. Can be.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a diagram schematically showing the configuration of an optical tomography system having a high resolution spectrometer according to the present invention.
2 is a view schematically showing the configuration of a spectrometer according to an embodiment of the present invention.
Figure 3 is a flow diagram for an optical tomography method having a high resolution spectrometer according to an embodiment of the present invention.
4 is a flowchart of a method of obtaining pixel information and wavelength information corresponding to each pixel of the present invention;
5 is a diagram showing a relationship of pixel-to-light intensity according to the movement of the mirror of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, in describing in detail the operating principle of the preferred embodiment of the present invention, if it is determined that the detailed description of the related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

The same reference numerals are used for portions having similar functions and functions throughout the drawings.

In addition, in the entire specification, when a part is referred to as being 'connected' to another part, it may be referred to as 'indirectly connected' not only with 'directly connected' . Also, to include an element does not exclude other elements unless specifically stated otherwise, but may also include other elements.

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

1 is a view schematically showing the configuration of an optical tomography system having a high resolution spectrometer according to the present invention. As shown in FIG. 1, the light source 110 includes an optical coupler 120, a reference unit 130, a sample unit 140, a spectrometer 150, and an image processor (not shown).

The optical coupler 120 divides the light emitted from the light source 110 into reference light and measurement light and outputs the light to each light path.

The reference unit 130 receives the reference light output from the optical coupler 120 and outputs the reference light reflected through the reflection path back to the optical coupler 120.

More specifically, the reference unit 130 converts the light output from the optical coupler 120 from the collimator 131 into parallel light, and collects the parallel light from the lens 132 and reflects it from the mirror 133. To output the reference light. In this case, the reference light reflected by the mirror 133 is incident on the optical coupler 130 again.

The sample unit 140 receives the measurement light output from the optical coupler 120 and emits the reflected measurement light reflected on the subject to the optical coupler 120.

More specifically, the sample unit 140 converts the light output from the optical coupler 120 from the collimator 141 into parallel light and collects the beams through the scanners 142a and 142b and the scanning lens 143. To the subject 144. In addition, the reflected light back scattered by the scatterer of the subject 144 is incident to the optical coupler 120 through the scan lenses 143, the scanners 142a and 142b, and the collimator 141. Here, the scanners 142a and 142b adjust the radiation direction of the optical signal in the X-axis direction and the Y-axis direction to scan the X-axis direction (horizontal direction) and the Y-axis direction (vertical direction) of the subject 144. Do this.

The spectroscope 150 receives the synthesized light of the reference light and the measurement light from the optical coupler 120 to detect pixel information and wavelength information using the mirror 154. That is, the spectroscope 150 moves by setting the movement displacement and the movement direction of the mirror 154, and acquires the pixel intensity array and the wavelength array by the incident and reflection of the synthesized light at the position of the mirror. Pixel information and wavelength information corresponding to each pixel are obtained.

The spectrometer will be described in more detail with reference to the accompanying drawings.

2 is a view schematically showing the configuration of a spectrometer according to an embodiment of the present invention. As shown in FIG. 2, the spectrometer 150 includes a collimator 151, a diffraction grating 152, a focusing lens 153, a line scan camera 155, a mirror 154, and a mirror. It comprises a drive unit (not shown).

The collimator 151 receives the beam synthesized from the optical coupler 120 and converts the beam into parallel light, and the diffraction grating unit 152 receives the parallel light converted by the collimator 151 and separates each wavelength. do.

The focusing lens 153 collects each light separated by each wavelength in the diffraction grating 152.

The line scan camera 155 receives the light intensity condensed by the focusing lens 153 differently according to the position of the mirror 154 provided at a position corresponding to the pixel of the line scan camera 155. That is, the mirror is moved by the set displacement and the set direction, and incident or reflected light input to the pixel of the line scan camera according to the + displacement or-displacement of the mirror.

The line scan camera 155 converts the light intensity into voltage at each position (wavelength) using a line sensor that is an array of photoelectric conversion elements.

The mirror 154 moves in a direction set by the mirror driver (not shown) or less in a micrometer unit, and the mirror driver has a structure in which it is transferred using a motor, a rail, or the like.

The image processor (not shown) obtains pixel information and wavelength information corresponding to each pixel by data processing the electrical signal output from the spectroscope 150.

3 is a flowchart of an optical tomography method having a high resolution spectrometer according to an embodiment of the present invention. As shown in FIG. 3, in the optical tomography method having the high-resolution spectrometer, the light emitted from the light source is divided into reference light and measurement light and output to each light propagation path (S31).

In addition, the step of receiving the reference light again receives the reference light reflected through the reflection path, receives the measurement light and radiates the reflected measurement light reflected back to the subject, combines and outputs the composite light (S32). ).

In more detail, the reference light is converted into parallel light, and the parallel light is collected to output the beam reflected through the mirror again.

The measurement light is converted into parallel light, and when the parallel light is emitted to the subject by adjusting the radiation direction of the optical signal in the X-axis direction and the Y-axis direction, the reflected light is outputted back scattered by the scattering body of the subject. do.

The synthesized light, which combines the output reference light and the measurement light again, is output through another light traveling path.

Then, the incident composite light is incident or reflected on the camera pixel according to the position of the mirror to be moved, and the light incident on the camera pixel is detected to obtain each pixel information and wavelength information corresponding to each pixel. It is performed (S33).

Finally, the step of controlling the optical system to focus on each unit pixel using the obtained pixel information and the wavelength information (S34).

4 is a flowchart illustrating a method of obtaining pixel information and wavelength information corresponding to each pixel of the present invention. As shown in FIG. 4, the method of obtaining the pixel information and the wavelength information corresponding to each pixel sets the movement displacement and the movement direction of the mirror (S41). That is, the displacement and the direction in which the mirror is moved are set corresponding to the camera pixels.

Subsequently, a first pixel intensity array information value PIA 1 and a first wavelength array information value WA 1 for the current position of the mirror are obtained (S42). That is, the first pixel intensity array information value PIA 1 and the first wavelength array information value WA 1 are obtained by the light incident on the pixel.

Next, the mirror in which the movement direction is set is moved by the set displacement (S43). Here, the mirror is preferably moved in the unit of μm or less.

More specifically, the second pixel intensity array information value PIA 2 and the second wavelength array information value WA 2 for the position at which the movement displacement of the mirror is moved in the + direction S44a or the − direction S44b are determined. Each is obtained (S45a, S45b).

The first pixel intensity array information value and the second pixel intensity array information value are calculated to obtain a predetermined pixel information value, the first wavelength array information value and the second wavelength array information value are calculated, and the wavelength information is calculated. A value is obtained (S46a, S46b).

More specifically, the predetermined pixel information value pixel (i) and the wavelength information value Wavelength (i) are the second pixel intensity in the first pixel intensity array information value when the movement displacement of the mirror is in the + direction. An array information value is subtracted and the first wavelength array information value is subtracted from the second wavelength array information value. At this time, the value of each calculated difference has a value of 0 or more (S46a).

In addition, when the displacement of the mirror is in the − direction, the first pixel intensity array information value is subtracted from the second pixel intensity array information value to obtain a predetermined pixel information value pixel (i), and the first wavelength array information is obtained. The wavelength information value Wavelength (i) is obtained by subtracting the second wavelength array information value from the value (S46b). At this time, the value of each calculated difference has a value of 0 or more (S46a).

In the calculating process, the mirror is continuously moved with a + or − displacement to calculate the first pixel intensity array information value until the first pixel intensity array information value is the same, and the second wavelength array information value is calculated. Computation is performed until the first wavelength array information value is the same (S47).

5 is a view showing a relationship between pixel and light intensity according to the movement of the mirror of the present invention. As shown in FIG. 5, the intensity of the pixel is shown along the direction in which the mirror of FIG. 2 moves. Here, it can be seen that the intensity input to the pixel changes as the mirror is moved. That is, the optical system can be controlled to focus on the unit pixel by accurately acquiring pixel information and wavelength information corresponding to each pixel according to the movement of the mirror, thereby improving spectral performance.

While the present invention has been particularly shown and described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, Of course, this is possible. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by the equivalents as well as the claims that follow.

Description of the Related Art
110 --- light source 120 --- optocoupler
130 --- Reference section 140 --- Sample section
150 --- Spectroscope 154 --- Mirror
155 --- line scan camera

Claims (12)

A light source;
An optical coupler for dividing the light emitted from the light source into reference light and measurement light and outputting the light to each light path;
A reference unit which receives the reference light output from the optical coupler and outputs the reference light reflected through the reflection path back to the optical coupler;
A sample unit receiving the measurement light output from the optical coupler and radiating the reflected light to a subject and outputting the reflected measurement light back to the optical coupler;
A spectroscope configured to detect pixel information and wavelength information by incident and reflecting the synthesized light of the reference light and the measurement light according to the moving position of the mirror in the optical coupler;
Including an image processor for generating an image by processing the pixel information and wavelength information output from the spectroscope,
The spectroscope moves by setting a movement displacement and a movement direction of the mirror, and acquires a pixel intensity array and a wavelength array by incidence and reflection of the synthesized light at a position of the mirror to correspond to each pixel information and each pixel. An optical tomography system having a high resolution spectrometer, characterized in that obtaining wavelength information.
The method of claim 1,
The spectroscope,
A collimator for receiving the synthesized beam and converting the beam into parallel light;
A diffraction grating unit for receiving the parallel light converted by the collimator and separating the light into each wavelength band;
A focusing lens for condensing each light separated by the diffraction grating portion;
A line scan camera which receives each light transmitted through the focusing lens and converts the light into an electrical signal;
A mirror provided between the focusing lens and the line scan camera and configured to move in a predetermined direction to reflect light input to a pixel of the line scan camera according to a moved position;
And a mirror driving unit for moving the mirror in a predetermined direction.
The method of claim 2,
And the mirror driving unit has a structure in which the mirror driving unit is transferred using a motor, a rail, or the like.
The method of claim 1,
The optical tomography system having a high-resolution spectrometer, characterized in that the mirror is moved in less than a unit.
The method of claim 1,
The reference unit
A collimator for converting the light output from the optical coupler into parallel light;
A lens for condensing parallel light output from the collimator;
And a mirror for reflecting the light collected by the lens.
The method of claim 1,
The sample unit
A collimator for converting the light output from the optical coupler into parallel light;
A scanner which scans the X-axis direction and the Y-axis direction of the subject by adjusting the parallel light output from the collimator in the radial direction;
And a scan lens configured to focus the radiation direction-controlled light on the subject in the scanner.
Dividing the light emitted from the light source into reference light and measurement light and outputting the light to each light path;
Receiving the reference light again to receive the reference light reflected through a reflection path, receiving the measurement light, radiating the reflected light to a subject, and inputting and combining the measured light to output composite light;
Injecting or reflecting the synthesized light into a camera pixel according to a position of a mirror to be moved, and detecting light incident on the camera pixel to obtain each pixel information and wavelength information corresponding to each pixel;
And controlling the optical system to focus on each unit pixel by using the acquired pixel information and the wavelength information.
8. The method of claim 7,
Acquiring the pixel information and the wavelength information corresponding to each pixel
Setting a movement displacement and a movement direction of the mirror;
Obtaining first pixel intensity array information and first wavelength array information for the current position of the mirror;
Moving the mirror in which the movement direction is set;
Obtaining second pixel intensity array information and second wavelength array information for a location after the mirror is moved;
The predetermined pixel information value is obtained by calculating the first pixel intensity array information value and the second pixel intensity array information value, and the wavelength information value is calculated by calculating the first wavelength array information value and the second wavelength array information value. Optical tomography method comprising a high resolution spectrometer, characterized in that it comprises the step of obtaining.
The method of claim 8,
In the obtaining of the predetermined pixel information value and the wavelength information value,
Subtracting the second pixel intensity array information value from the first pixel intensity array information value and subtracting the first wavelength array information value from the second wavelength array information value when the shift of the mirror is in the + direction. An optical tomography method provided with a high resolution spectrometer.
The method of claim 8,
In the obtaining of the predetermined pixel information value and the wavelength information value,
And subtracting the first pixel intensity array information value from the second pixel intensity array information value and subtracting the second wavelength array information value from the first wavelength array information value when the shift of the mirror is in the-direction. An optical tomography method provided with a high resolution spectrometer.
The method of claim 9 or 10,
In the process of calculating
The mirror is continuously moved with a + or − displacement to calculate until the first pixel intensity array information value is equal to the second pixel intensity array information value, and the second wavelength array information value and the first wavelength array information are calculated. A strong tomography method with a high resolution spectrometer, characterized in that until the value is equal.
The method of claim 8,
In the step of moving the mirror
The optical tomography method of claim 1, wherein the mirror is moved in a micrometer unit or less.

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