KR20160117816A - Dual focusing optical coherence tomography with balanced detection - Google Patents

Abstract

The objective of the present invention is to provide a balancing detecting dual optical coherence imaging device. The present invention comprises: a light source unit (100) for generating light of optical bands; a main light distributor (120), equipped with one or more balancing light distributor which distribute and process the light, generated in the light source unit; an interference unit (200), equipped with an interference part (201) (including a first interference part and a second interference part), to form interference signals against one or more focusing areas of a subject by using the light distributed by the main light distributor, a common sample arm (203), commonly connected to the interference part (including the first interference part and the second interference part) for forming differences in the light path for the one or more focusing areas of a subject of light radiated by the interference part (including the first interference part and the second interference part) and a balancing switching unit (300) for outputting interference signals alternately, which are formed by the signals, transmitted by the interference part, passing through at least parts of the main light distributor; and a detection unit (400) for converting the interference signal, outputted from the balancing switching unit, into electric signals.

Description

[0001] DUAL FOCUSING OPTICAL COHERENCE TOMOGRAPHY WITH BALANCED DETECTION [0002]

The present invention relates to a coherent imaging apparatus, and more particularly, to a coherent coherent imaging apparatus capable of acquiring image information for a plurality of regions through a single scanning operation.

Recently, optical coherence tomography (OCT), which is popular in optical research and medical device industry, is a technology that enables non-invasive tomographic imaging of microstructure in living tissue using near-infrared light. Since successful commercialization of ophthalmic optic coherent tomography for ocular and retinal imaging, there has been active research on the commercialization of a variety of OCT products such as endoscopic OCT, OCT for skin diagnosis and OCT for the diagnosis of cancer globally, The fields are improvement of image acquisition speed for clinical applications, acquisition of high-resolution images, and technology for reducing production costs. The optical coherent tomographic imaging system is composed of a time domain optical coherence tomography (TD-OCT), a spectral domain optical coherence tomography (SD-OCT), a wavelength tunable optical coherence tomography (SS-OCT). The system developed in the present invention was developed based on a spectral domain optical coherence tomography (SD-OCT), and basically, the spectral domain coherent tomography apparatus uses a Michelson interferometer. Light from a near-infrared light source having a broad wavelength band passes through an optical distributor and is divided into a sample stage and a reference stage.

The light incident on the sample is inversely scattered at different depths of the sample structure, and the light incident on the reference end is reflected on the fixed mirror of the reference stage. The light reflected from the sample stage and the reference stage is again reflected at the optical distributor, and interference occurs when the optical path difference of the two separated lights is smaller than the interference length of the light source. The generated interfering signal is detected as a signal in the frequency domain through the spectroscope and can be used to image the depth of the sample through inverse Fourier transform.

However, in the case of OCT according to the related art, in particular, the existing spectral domain optical coherence tomography (SD-OCT) is exposed to auto-correlation (AC) occurring between the DC noise and the sample internal structure , Which causes distortion of the tomographic image.

In addition, there is a disadvantage in that the sensitivity is lower than that of a wavelength variable light source coherent apparatus that performs balance detection using a balance detector. In order to compensate for this, many studies have been conducted to apply balance detection in SD-OCT, such as using a multi-line camera or using two spectrometers. However, the above-mentioned methods cause problems such as a slow detection time, an additional cost, and a detection error in a high-frequency signal band caused by misalignment between two spectrometers.

Also, an OCT can be used to obtain image information for different focus regions, such as the eyeball. The OCT system according to the prior art constructs two interferometers using one or two light sources and two spectrometers This is a common system. In order to visualize the anterior segment and the retina, the focus of light must be located at each position, so one light is focused on the anterior segment by the objective lens and the other is focused on the objective lens So that the retina is focused through the lens of the eyeball. This method can not avoid the price increase by using two of the most expensive parts of the OCT system, the light source and the spectroscope. In addition, the use of two spectrographs requires the use of two frame grabbers, which transfer the depth information obtained by the camera to a computer, and two spectrometers must be controlled simultaneously by one software. Follow.

Another way to visualize the entire eye is to use only one light to image the anterior segment and the retina. The beam size is narrowed to about 1 to 1.5 mm and the depth of focus is greatly increased by using an objective lens having a long focal length to acquire an image up to the retina. However, since this method does not focus on the retina, the quality of the image is so low that it can not be used in clinical practice.

The present applicant has proposed a method for acquiring an image of an entire eye including the anterior segment and the retina in Patent Application No. 10-2012-0005919. However, the prior art has a problem in obtaining a clear image. In the anterior segment, the length from the surface of the cornea to the undersurface of the lens is long, and the sensitivity decreases from the upper side of the lens toward the outer side and from the inner side, resulting in an unclear image. To solve this problem, the exposure time of the camera is increased in order to improve the sensitivity. However, the degradation of the image acquisition speed and the degradation of the image acquisition speed result in the recovery of the complex conjugate image. When a complex conjugate image appears, it acts as a noise because it overlaps with the image to be obtained, and it has a considerable influence when reconstructing it as a 3D image.

Accordingly, the present invention provides a structure that eliminates noise to enable high-quality image acquisition, improves system stability, implements imaging to a deep region of a sample, enables rapid image acquisition, and reduces manufacturing costs The present invention also provides a coherent image pickup apparatus of the present invention.

Also, the present invention provides a simple optical coherence imaging apparatus for acquiring image information for substantially different focus regions from each other at the same time, minimizing optical elements, improving the accuracy of image information, and reducing manufacturing costs .

According to an aspect of the present invention, there is provided a light source device including: a light source part generating light in a wide band; A main optical distributor (120) including at least one balancing optical distributor for distributing and propagating light generated from the light source unit; An interference unit for forming an interference signal with respect to a focus region of the subject by using each of the lights distributed from the main optical distributor; and an interference unit, connected to the interference unit, An interference unit 200 having a common sample arm forming a light path for the main optical distributor and a balancing switching unit for alternately switching-outputting an interference signal formed by the signal transmitted from the interference unit through at least a part of the main optical distributor; And a detection unit for converting the interference signal output from the balancing switching unit into an electrical signal.

The balancing switching unit 300 includes: a balancing optical switch 310 receiving an interference signal distributed from at least a part of the main optical distributor and alternately outputting the interference signal to the detection unit; And a balancing delay unit disposed in one of two optical paths between at least a part of the main optical distributor and the balancing optical switch for delaying the transmission of an interference signal transmitted from the main optical distributor to the balancing optical switch 320).

In the balanced detection optical coherence imaging apparatus, the balancing delay unit may be an optical fiber having a predetermined length.

The main optical distributor may include: a first balancing optical splitter 121 for distributing and propagating the light received from the light source unit; and a second balancing optical splitter 121 for receiving the signal transmitted from the interference unit, And a second balancing optical distributor 123 for forming and redistributing a signal and outputting the signal.

The interferometer 201 may further include: a sample arm 220 having a sample arm collimator for receiving the light distributed from the main optical distributor; A reference arm collimator for receiving light distributed from the main optical distributor and a reference arm for reflecting the light transmitted from the reference arm collimator and returning the light to the reference arm collimator.

The common sample arm (202) includes: a common arm optical scanner (204) for irradiating light transmitted through the sample arm collimator toward a focus region of the test subject; And a common arm objective lens 205 that focuses the light irradiated from the common-arm optical scanner and irradiates the focused light onto the focused region of the inspected object and transmits the light reflected from the focused region of the inspected object back to the common-arm optical scanner It is possible.

In the balanced monitoring optical coherence imaging apparatus, an optical circulator (110) is connected to the first balancing optical splitter and the second balancing optical splitter, respectively, and the optical circulators are connected to the sample arm and the reference And transmits the light transmitted from the first balancing optical splitter to the sample arm and the reference arm and transmits the light reflected and transmitted from the sample arm and the reference arm to the second balancing optical splitter have.

The balancing optical distributor 120 may further include: a light distributor 120 for distributing the light received from the light source to at least a part of the interferometer, receiving a signal reflected and transmitted from the interferometer, And may be a first balancing optical splitter 121 for advancing to another part.

The interferometer 201 may further include: a sample arm 220 having a sample arm collimator for receiving the light distributed from the main optical distributor; A reference arm collimator for receiving light distributed from the main optical distributor and a reference arm for reflecting the light transmitted from the reference arm collimator and returning the light to the reference arm collimator.

The common sample arm (202) includes: a common arm optical scanner (204) for irradiating light transmitted through the sample arm collimator toward a focus region of the test subject; And a common arm objective lens 205 that focuses the light irradiated from the common-arm optical scanner and irradiates the focused light onto the focused region of the inspected object and transmits the light reflected from the focused region of the inspected object back to the common-arm optical scanner It is possible.

In the balanced detection optical coherence imaging apparatus, an optical circulator 110 is connected to the light source unit and the first balancing optical splitter, and the optical circulator is connected to the balancing switching unit, And transmits the light from the first balancing optical splitter to the balancing switching unit.

The detection unit 400 may include: a detection collimator 410 for outputting the interference signal selected by the balancing switching unit as parallel light; a light source 410 for diffracting light incident from the detection collimator 410; A detection lens 430 for focussing the light diffracted by the detection diffraction grating 420 and a detector 440 for converting the diffracted light incident from the detection lens into an electrical signal It is possible.

In the balancing detecting optical coherence imaging apparatus, at least one of the main optical distributors may include an optical fiber splitter.

The balancing detecting optical coherence imaging apparatus includes a control unit 20 for receiving an electrical signal from the detection unit, a storage unit 30 connected to the control unit and storing preset data, An arithmetic unit (40) for calculating an image information by executing an arithmetic operation in accordance with an electric signal and preset data of the storage unit in accordance with a control signal of the control unit; And a display unit 50 may be provided.

According to another aspect of the present invention, there is provided a light source device including: a light source part generating light in a wide band; A main optical distributor (120) including at least one balancing optical distributor for distributing and propagating light generated from the light source unit; An interference unit 201 for forming an interference signal for at least one focus region of the subject using the light distributed from the main optical distributor, and an interference unit 201, which is commonly connected to the interference unit, A common sample arm (203) for forming optical path differences with respect to at least one focus region of the specimen; and a balancing unit for alternately switching and outputting an interference signal formed and distributed through at least a part of the main optical distributor An interference unit 200 having a switching unit 300; And a detection unit (400) for converting the interference signal output from the balancing switching unit into an electrical signal.

The balancing switching unit 300 includes: a balancing optical switch 310 receiving an interference signal distributed from at least a part of the main optical distributor and alternately outputting the interference signal to the detection unit; And a balancing delay unit disposed in one of two optical paths between at least a part of the main optical distributor and the balancing optical switch for delaying the transmission of an interference signal transmitted from the main optical distributor to the balancing optical switch 320).

In the balancing detecting optical coherence imaging apparatus, the balancing delay unit 320 may be an optical fiber having a predetermined length.

The main optical distributor 120 includes: a first balancing optical splitter 121 for distributing and propagating light received from the light source unit; and a second balancing optical splitter 121 for inputting a signal transmitted from the interference unit, And a second balancing optical splitter 123 for forming the interference signal, redistributing the interference signal, and outputting the resultant signal.

The interferometer 201 may further include: a sample arm 220 having a sample arm collimator for receiving light distributed from the main optical distributor; A reference optical switch 234 that receives light distributed from the main optical distributor and is alternately switched in a preset manner, a first reference arm collimator and a second reference arm that are alternately received light from the reference optical switch, A first reference mirror and a second reference mirror for reflecting light transmitted from the collimator, the first reference arm collimator and the second reference arm collimator, respectively, and returning the light to the first reference arm collimator and the second reference arm collimator, The first reference arm 230a and the second reference arm 230b, which include the first reference arm 230a and the second reference arm 230b, (230).

The common sample arm comprises: a common arm optical scanner (204) for irradiating light transmitted through the sample arm collimator toward a different focus region of the subject; Irradiating the light irradiated from the optical scanner to different focus areas of the subject and transmitting the reflected light from different focus areas of the subject to the common arm optical scanner again, And a common-arm optical path dispersion unit 206 disposed between the subject and the common-arm optical scanner so as to form a light path difference of light to be transmitted.

In the balancing detecting optical coherence imaging apparatus, the common-arm optical path distributing unit 206 may be configured to distribute the light radiated from the optical scanner to be formed in the same direction as the traveling direction of the light irradiated from the optical scanner A dispersed first optical splitter 2061 for forming a first sample optical path PathP and a second sample optical path PathS formed in a direction perpendicular to the traveling direction of light emitted from the optical scanner, A dispersion second optical distributor (2062) disposed between the inspected object and the first sample optical path path (Path P) and the second sample optical path path (PathS) opposite to the first optical splitter, The light that is transmitted between the optical distributor 2062 and the subject and that is transmitted through the second optical distributor 2062 is irradiated to different focus areas of the subject and is focused on different focus areas of the subject A dispersive objective lens 2069 for transmitting the reflected light to the second dispersive optical distributor 2062 and a second objective lens 2070 disposed on the second optical path S Diffracted second sample optical path mirrors 2065 and 2067 that are formed to be different from the first sample optical path PathP and a second sample optical path path that does not intersect with the first sample optical path PathP And a dispersed second sample optical path focusing lens 2063 disposed on the optical path.

In the balanced detection optical coherence imaging apparatus, the dispersion second sample optical path focusing lens 2063 is disposed between the dispersion first optical distributor 2061 and the dispersion second sample optical path mirror 2065 It is possible.

The first reference arm 230a includes a first reference optical path PathRP formed between the first reference arm collimator 233a and the first reference mirror 235a, And the second reference arm 230b has a second reference optical path RS formed between the second reference arm collimator 233b and the second reference mirror 235b, And common reference light distributors 241 and 243 through which the light on the first reference optical pathRP and the light on the second reference optical pathRAS share.

The first reference mirror of the first reference arm 230a may be a distributed first reference light path that reflects and transmits light inputted through the common reference light distributors 241 and 243, Mirror 235a and the second reference mirror of the second reference arm 230b is a dispersed second reference optical path mirror 235b that reflects and transmits the light input through the common reference light distributors 241 and 243 It is possible.

The first reference polarization controller 236a and the second reference polarization controller 236b are provided between the reference optical switch 234 and the first reference arm collimator 233a and the second reference arm collimator 233b, And two reference polarization controllers 236b may be respectively provided.

In the balanced monitoring optical coherence imaging apparatus, optical circulators (110, 111, 113) are disposed in the first balancing optical splitter (121) and the second balancing optical splitter (123) The reference arm 110 is connected to the sample arm 220 and the reference arm 230 so that the light transmitted from the first balancing optical splitter 121 is transmitted to the sample arm 220 and the reference arm 230, And transmits the light reflected and transmitted from the sample arm 220 and the reference arm 230 to the second balancing optical distributor 123. [

The balancing optical divider of the main optical distributor 120 may be configured to: distribute the light received from the light source unit to advance to at least a part of the interferometer, receive a signal reflected and transmitted from the interferometer, And may be a first balancing optical splitter 121 for advancing to another part of the interferometer.

The interferometer includes: a sample arm 220 having a sample arm collimator 223 for receiving light distributed from the main optical distributor; and a beam splitter 230 for splitting the sample arm 220 A reference optical switch 234 that receives light distributed from the main optical distributor 120 and is alternately switched in a preset manner, a first reference arm collimator 234 that receives light from the reference optical switch alternately, The first reference arm collimator 233a and the second reference arm collimator 233b reflect the light transmitted from the first reference arm collimator 233a and the second reference arm collimator 233b and the first reference arm collimator 233a and the second reference arm collimator 233b, Which includes a first reference mirror 235a and a second reference mirror 235b for returning to the second reference arm collimator 233b, (230a) and the may include a reference arm 230, including the second reference arm (230b).

The common sample arm 202 may include: a common arm optical scanner 204 for irradiating light transmitted through the sample arm collimator toward a different focus region of the subject; Irradiating the light irradiated from the common arm optical scanner to different focus areas of the subject and transmitting the light reflected from different focus areas of the subject to the common arm optical scanner again, And a common-arm optical path dispersion unit 206 disposed between the subject and the common-arm optical scanner so as to form a light path difference of light irradiated to the common-arm optical scanner.

In the balancing detecting optical coherence imaging apparatus, the common-arm optical path distributing unit 206 may be configured to distribute the light radiated from the optical scanner to be formed in the same direction as the traveling direction of the light irradiated from the optical scanner A dispersed first optical splitter 2061 for forming a first sample optical path PathP and a second sample optical path PathS formed in a direction perpendicular to the traveling direction of light emitted from the optical scanner, A dispersion second optical distributor (2062) disposed between the inspected object and the first sample optical path path (Path P) and the second sample optical path path (PathS) opposite to the first optical splitter, The light that is transmitted between the optical distributor 2062 and the subject and that is transmitted through the second optical distributor 2062 is irradiated to different focus areas of the subject and is focused on different focus areas of the subject A dispersive objective lens 2069 for transmitting the reflected light to the second dispersive optical distributor 2062 and a second objective lens 2070 disposed on the second optical path S Diffracted second sample optical path mirrors 2065 and 2067 that are formed to be different from the first sample optical path PathP and a second sample optical path path that does not intersect with the first sample optical path PathP And a dispersed second sample optical path focusing lens 2063 disposed on the optical path.

In the balanced detection optical coherence imaging apparatus, the dispersion second sample optical path focusing lens 2063 is disposed between the dispersion first optical distributor 2061 and the dispersion second sample optical path mirror 2065 It is possible.

The first reference arm 230a includes a first reference optical path PathRP formed between the first reference arm collimator 233a and the first reference mirror 235a, And the second reference arm 230b has a second reference optical path RS formed between the second reference arm collimator 233b and the second reference mirror 235b, And common reference light distributors 241 and 243 through which the light on the first reference optical pathRP and the light on the second reference optical pathRAS share.

The first reference mirror of the first reference arm 230a may be a distributed first reference light path that reflects and transmits light inputted through the common reference light distributors 241 and 243, Mirror 235a and the second reference mirror of the second reference arm 230b is a dispersed second reference optical path mirror 235b that reflects and transmits the light input through the common reference light distributors 241 and 243 It is possible.

The first reference polarization controller 236a and the second reference polarization controller 236b are provided between the reference optical switch 234 and the first reference arm collimator 233a and the second reference arm collimator 233b, And two reference polarization controllers 236b may be respectively provided.

The optical circulator of the first balancing optical splitter and the optical circulator are connected to the balancing switching unit so that the light emitted from the light source unit can be transmitted to the first and second balanced optical splitter, 1 balancing optical divider, and may transmit the light transmitted from the first balancing optical splitter to the balancing switching unit.

The detection unit may include: a detection collimator for outputting the interference signal selected by the balancing switching unit as parallel light; a detection diffraction grating for diffracting light incident from the detection collimator; A detection lens for focussing the light diffracted by the detection diffraction grating and a detector for converting the diffracted light incident on the focal point from the detection lens into an electrical signal.

In the balancing detecting optical coherence imaging apparatus, at least one of the main optical distributors may include an optical fiber splitter.

The control unit receives the electrical signal from the detection unit. The storage unit stores the preset data. The electrical signal transmitted from the detection unit and the electrical signal transmitted from the storage unit And a display unit for displaying the image information in accordance with the image control signal of the control unit. The image display apparatus according to the present invention may further comprise:

The balancing detecting optical coherence imaging apparatus according to the present invention having the above-described configuration has the following effects.

First, the balancing detec- ting optical coherence imaging apparatus according to the present invention removes noise to enable high-quality image acquisition, improves system stability, implements imaging to a deep region of a sample, enables rapid image acquisition , And a simple configuration can reduce the manufacturing cost.

In particular, the present invention can remove DC noise and AC noise to obtain high quality images. In addition, fixed-pattern noise generated by fluctuation of the light source power according to time changes can be captured to enhance the stability of the system and to improve the sensitivity of the system to image the deep region of the sample The cost reduction structure can reduce system size, improve durability, and perfectly detect balance in high frequency signal band.

Second, it enables simultaneous and alternative image acquisition through a single scan on a single object, minimizes optical components, reduces the need for high intensity light sources, and increases the intensity of light It is possible to solve the problem that the interference signal is weakened to half intensity and to provide a structure for preventing the deterioration of the performance due to the occurrence of an error other than the same spectrometer when the interference signal in the high frequency range is detected in balance have.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

1 is a schematic block diagram of a balanced detection optical coherence imaging apparatus according to an embodiment of the present invention.
2 is a schematic block diagram of a modification of Fig.
3 is a schematic block diagram of a structure that enables image acquisition of a phase-to-focus image of a subject's eye of a balancing detec- ting optical coherence imaging device according to an embodiment of the present invention.
Fig. 4 is a schematic block diagram of a modification of Fig. 3; Fig.
Figures 5 and 6 are schematic illustrations illustrating balancing detection.

Hereinafter, a balancing detecting optical coherence imaging apparatus will be described with reference to the drawings.

FIG. 1 is a schematic block diagram of a balanced detection optical coherence imaging apparatus according to an embodiment of the present invention. FIG. 2 is a schematic block diagram of a balancing detecting optical coherence imaging apparatus according to another embodiment of the present invention. 3 is a schematic block diagram of a balanced detection optical coherence imaging apparatus for acquiring image information for different focus regions according to another embodiment of the present invention, A schematic block diagram of a balanced detection optical coherence imaging apparatus for acquiring image information for mutually different focus regions according to another embodiment of the present invention is shown.

The balancing detecting optical coherence imaging apparatus 10 according to an embodiment of the present invention includes a light source 100, an interference unit 200 having an interference unit 201 and a common sample arm 202, (300), and a detection unit (400).

The light source unit 100 generates light of a wide band, and the light source unit 100 includes a low coherence light source in the present embodiment. Hereinafter, a case where a light source part of a low-coherent light source and a line scan camera as a detector are provided and a detection unit as a spectroscopic unit that implements a spectroscopic function is provided will be described.

The average time interval at which a light wave arriving at a point on an arbitrary point oscillates predictably and maintains a sinusoidal form without a phase change is called a coherence time. This is called a coherence time, to be. The light wave propagates in a sinusoidal form only for a time interval in which the phase is kept constant. The spatial distance of the light wave oscillating regularly before the phase changes arbitrarily is called the interference distance coherence length) and is used as a measure to grasp the degree of spectroscopically pure. A low-coherent light source is a light source having a short interference distance of a light wave and has a wide spectrum band. The transmission path between the components for transmitting the light of the wide band generated from the light source 100 is implemented by an optical fiber.

The light of the wide band generated from the light source unit 100 is transmitted to the main optical distributor 120. The main optical distributor 120 includes at least one balancing optical distributor for distributing the generated light from the light source unit 100 . 1, the main optical splitter 120 includes a first balancing optical splitter 121 and a second balancing optical splitter 123. The first balancing optical splitter 121 receives the light from the light source 100 The second balancing optical splitter 123 receives the signal transmitted from the interfering unit 201 and forms a trunk signal, redistributes the trunk signal, and outputs the trunk signal. That is, the first balancing optical splitter 121 and the second balancing optical splitter 123 of the main optical distributor 120 are connected to the interference unit 201 of the interference unit 200 to transmit light from the light source unit, Receives the light reflected from the light source 201, forms and distributes an interference signal, and outputs the signal to the balancing switching unit 300 to transmit the interference signal to the detection unit 400 through the balancing switch unit 300. The balancing optical splitters 121 and 123 of the main optical distributor 120 are implemented as optical fiber splitters and the phase difference between the lights outputted through the first balancing optical splitter 121 and the second balancing optical splitter 123 is π / . 1, the first balancing optical splitter 121 and the second balancing optical splitter 123 are connected to each other with the interfering unit 201 interposed therebetween. The first balancing optical splitter 121 and the second balancing optical splitter 123 are connected to each other, A phase difference of? / 2 is formed between the lights output through the splitter 121 and a phase difference of? / 2 is generated between the lights output through the second balancing optical splitter 123, A phase difference of? Is formed between the light as the interference signal output through the sample arm 220 of the interference unit 201 and the reference arm 230 and the second balancing optical splitter 123 of the main optical distributor.

5 and 6 show a schematic explanatory diagram of two interference signals 1 (a) and 2 (b) formed through the main optical distributor 120 and the interference unit 201, Can be separated into a DC component and an AC component. In the case of separating the interference signal 1 (a) (DC + AC) and the interference signal 2 (b) (DC + AC (πshift)) into a DC component and an AC component, ≪ / RTI > Therefore, when subtracting the two interference signals output through the balancing switching unit and the detection unit via the main optical distributor, the DC component is removed and the interference signal of the interference signal represented by the AC component representing the internal information of the sample unit S The size can be doubled (2AC = AC-AC (πshift)) to achieve balance detection.

When the main optical distributor 120 includes two balancing optical splitters 121 and 123 as in the present embodiment, the second balancing optical splitter 123 for transmitting light to the balancing switching unit 300, ), It is desirable to set the light distribution ratio to 50:50. On the other hand, in the case of the first balancing optical splitter 121 that divides the light input from the light source unit 100 and transmits the split light to the interferometer 201, the size ratio of the divided light can be evenly divided. However, It is possible to increase the transmission ratio of light to one side of the interferometer 201 to be divided, for example, to the side of the sample arm, thereby making it possible to obtain more accurate image information.

Meanwhile, the signal output through the second balancing optical splitter 123 is transmitted to the balancing switching unit 300. The balancing switch 300 of the present invention includes a balancing optical switch 310 and a balancing delay unit 320. The balancing optical switch 310 is connected to at least part of the main optical distributor 120, The balancing delay unit 320 receives the interference signal distributed from the second balancing optical distributor 123 and outputs the interference signal to the detection unit 400. The balancing delay unit 320 receives at least part of the main optical distributor 120, Which is an optical path between the second balancing optical splitter 123 and the balancing optical switch 310. The second balanced optical splitter 123 of the main optical splitter 120 is connected to the balanced optical switch And delays the transmission of the interference signal to the base station 310.

The balancing delay unit 320 of the present invention may have various configurations within a range that functions to delay the transmission time of the light signal input from the main optical distributor 123, that is, the second balancing optical splitter 123, to the balancing optical switch 310 However, in this embodiment, the balancing delay unit 320 is implemented with an optical fiber having a predetermined length. In the present embodiment, the balancing delay unit 320 is implemented with an optical fiber having a length of about 2 km, but it can be variously modified according to design specifications.

In the present invention, the light generated from the light source unit 100 is transmitted to the main optical distributor 120 and is transmitted to the interferometer 201, and the sample arm of the interferometer 201 and the light reflected from the reference arm are transmitted to the balancing switching unit It is possible to minimize the use of the optical element in the process of transmitting the light to the optical element 300, thereby minimizing the reduction rate of light transmission occurring in the process of passing through the optical element. That is, the balancing detecting optical coherence imaging apparatus 10 of the present invention is provided with an optical circulator 110, which performs optical transmission to a desired side and transmits light to an undesired side Execute the blocking function. In this embodiment, the optical circulator 110 is disposed between the main optical distributor 120, that is, between the first balancing optical splitter 121 and the second balancing optical distributor 123, And a sample arm 220 is connected to the sample. The optical circulators 110 and 112 and 113 are connected to the sample arm 220 and the reference arm 230 to transmit the light transmitted from the first balancing optical distributor to the sample arm 220 and the reference arm 230, The sample arm 220 and the reference arm 230 to the second balancing optical splitter 123 and the balancing switching unit 300 without transmitting the light to the first balancing optical splitter 121.

An optical isolator is disposed between the first balancing optical splitter 121 of the main optical distributor 120 and the light source unit 100 so that the light of the broadband light generated from the light source unit 100 The main light distributor 120 may be provided with a component for blocking transmission of reflected light to the light source unit 100 to protect the light source unit 100 and reducing optical loss.

The first balancing optical splitter 121 of the main optical distributor 120 divides the light of the wide band transmitted from the light source unit 100 and transmits the divided light to the interference unit 200. The interference unit 200 includes an interference unit 201 and a common sample arm 202. The interference unit 201 is provided in the main optical distributor 120, that is, in the first balancing optical splitter 121 in this embodiment, And the common sample arm 202 is connected to the interference unit 201 to form a reflection path and a reflection path to form a reflection path and a reflection path for forming an interference signal with respect to the focus area of the subject S using the transmitted light, Thereby forming a light path for the focus region of the illuminated object of the light irradiated by the light source 201.

The sample arm 220 is provided with a sample arm collimator 223 and a sample arm collimator 223 is disposed between the sample arm optical fiber 221 and the sample arm optical fiber 221. The sample arm collimator 223 includes a sample arm 220 and a reference arm 230, The first balancing optical splitter 121 is connected to the optical circulator 112 connected to the first balancing optical splitter 121 and more specifically to the first balancing optical splitter 121 through the first balancing optical splitter 121, The light formed by the collimated light is transmitted from the sample arm collimator 223 through the common sample arm 202 to the sample collimator 212 via the sample arm 202, Focus area.

The other one of the lights split from the light source unit 100 through the first balancing optical splitter 121 is transmitted to the reference arm 230 via the optical circulator 113. The reference arm 230 is a reference arm collimator, (232) and a reference mirror (235). The reference arm collimator 233 is connected to the first balancing optical splitter 121 and the optical circulator 113 through the reference arm optical fiber 231. The parallelism between the reference arm collimator 233 and the reference mirror 235 can be smoothly formed through the structure of the reference arm optical fiber 231. The light intensity of the light due to the reference arm optical fiber 231 The reference polarization controller 237 may be disposed between the optical circulator 113 and the reference arm collimator 233 in order to reduce such influence. The reference polarization controller 237 may maximize the light intensity of the broadband light from the light source unit and form the shape of the light close to Gaussian.

The reference arm collimator 233 also makes the light in the wide band parallel to the sample collimator 231a. The parallel light emitted from the reference arm collimator 233 is irradiated to the reference mirror 235. The irradiated light is reflected by the reference mirror 235 and returned to the optical circulator 113 via the reference arm collimator 233. The optical circulator 113 transmits the returned light to the second The light reflected by the reference mirror 235 and returned to the optical circulator 113 passes through the sample arm 202 to be passed through the sample arm 220, S and returning to another optical circulator 112 and the main light distributor 120, that is, the second balancing optical splitter 123, to form interference phenomenon, Thereby forming an interference signal for image acquisition with respect to the focus area.

As described above, the main optical distributor is implemented as a fiber coupler so that a stable and uniform light distribution and output can be achieved regardless of the incident angle of light, and a compact and compact structure can be achieved.

The common sample arm 202 includes a common arm optical scanner 204 and a common arm objective lens 205. The common-arm optical scanner 204 receives light transmitted through the sample arm collimator 223. The common-arm optical scanner 204 may be implemented as a galvanometer type, and a structure in which a mirror is mounted on the galvanometer And rotates at a predetermined angle and speed. Light passing through the common arm optical scanner 204 is irradiated to the subject S, more specifically, the focus region P of the subject S via the common arm objective lens 205. [ One common arm objective lens 205 is provided in the present embodiment. The number and type of the common arm objective lenses are not limited to this, and various configurations are possible depending on the relationship between the design specification and the focus area of the object to be measured Do.

Therefore, the sample arm 220 of the interferometer 201 of the interference unit 200, the reference arm 230, and the common sample arm 202 are connected to each other through the first balancing optical splitter 121 of the main optical distributor 120, The light that has passed through the sample arm 220 among the light beams of the distributed and transmitted light is transmitted through the common sample arm 202 to be irradiated to the respective focus regions P1 and P2 of the inspected object P, The reflected light enabling the acquisition of the image signal for the image P is transmitted back to the optical circulator 112 via the common sample arm 202 and the sample arm 220 as opposed to the incident light. At the same time, the light transmitted to the reference arm 230 is reflected by the reference mirror 235 and returns to the other optical circulators 113 through the reverse path. The reflected light for obtaining the image of the focus region P of the subject S passing the sample arm 220 and the common sample arm 202 and the reflected light for obtaining the image of the reference mirror 235 through the reference arm 230, Is transmitted to the second balancing optical splitter 123 of the main optical distributor 120 and the sample arm introduced into the second balancing optical splitter 123 is interfered with the light passing through the reference arm and the light passing through the sample arm The interference signal due to the second balanced optical splitter 123 can be formed.

The interference signal formed in the second balancing optical splitter 123 of the main optical distributor 120 is transmitted to the balancing switch unit 400. As described above, the balancing switch unit 300 includes the balancing optical switch 310, And a delay unit 320. That is, all of the light that is distributed by the second balancing optical splitter 123 is introduced into the balancing optical switch 310. The balancing optical switch 310 performs the switching operation to sequentially transmit the light as the interference signal, that is, The interference light for the divided focus region P at the splitter 123 and the interference light for the second focus region P2 through the second interference portion 201b, To another detection unit (400). On the other hand, a phase difference of? / 2 is generated between the lights split by the first balancing optical splitter 121, and a phase difference of? / 2 is additionally generated between the lights as the interference signal divided by the second balancing optical splitter 123 A phase difference of π is formed between the light as the interference signal ultimately transmitted from the second balancing optical splitter 121 to the balancing optical switch 310 of the balancing switching unit 300. The balancing delay unit 320 is disposed in one of the paths of the interference signal transmitted from the second balancing optical splitter 121 to the balancing optical switch 310 of the balancing switching unit 300 to delay the signal transmission by a preset time , It may be possible to continuously transmit the image obtained at the same time with respect to the focus area during switching of the balancing optical switch 310.

The balancing optical switch 310 uses a high-speed optical switch for an optical range of 800 to 1300 nm in the present embodiment. The balancing optical switch 310 performs selective operation through a control signal, To the detection unit 400 to perform balancing detection that excludes the DC components as shown in FIGS. 5 and 6, thereby achieving a clearer visualization of the focus area.

Also, at least one switching polarization controller 330 may be disposed between the second balancing optical splitter 123 and the balancing optical switch 310. That is, in the present embodiment, the switching polarization controller 330 minimizes the loss of the strength of the transmitted interference signal, thereby achieving stable transmission of the interference signal.

The detection unit 400 converts an interference signal transmitted from the balancing switching unit 300 into an electrical signal. The detection unit 400 (see FIG. 3) implemented as a spectroscopic unit includes a detection collimator 410, a detection diffraction grating 420, a detection lens 430, and a detector 440. The detection collimator 410 converts the interference signal selected and transmitted from the optical switch 300 into parallel light and outputs the parallel light to the detection diffraction grating 420.

The detection diffraction grating 420 diffracts an interference signal as incident parallel light. In this embodiment, a transmission grating of 1800 roots / mm is used for the detection diffraction grating 420, Various options are available.

The light diffracted by the detection diffraction grating 420 is transmitted to the detector 440 through the detection lens 430. In this embodiment, the detector 440 is implemented as a line scan camera with a scan rate of 70000 lines / s.

In some cases, a prism may be disposed between the detection lens 430 and the detector 440. The prism disposed between the detection lens 430 and the detector 440 can detect a linear value of the wave number from the detector 440 in contrast to a conventional spectroscope that obtains a linearly increasing value with respect to the wavelength with a camera, So that it is possible to replace the function of linearly changing the value of the wave number by processing it in a software manner, so that it is possible to acquire more accurate image information.

The electrical signal converted from the interference signal through the detection unit 400 is transmitted to the control unit 20, and is converted into a digital signal in this process. 1, the balancing detecting optical coherence imaging apparatus 10 of the present invention includes a control unit 20, a storage unit 30, an operation unit 40, and a display unit 50, (20) is electrically connected to the storage unit (30) and the calculation unit (40). The storage unit 30 may store preset data including preset image conversion data necessary for converting an electrical signal from the detection unit 400 into a video signal. The arithmetic unit 40 performs a predetermined arithmetic process in accordance with the arithmetic control signal of the controller 20, that is, the arithmetic unit 40 performs inverse fast Fourier transform (IFFT) and / or k- (k-domain calibration). The control unit 20 uses the preset image conversion data stored in the storage unit 30 in accordance with the calculation result to cause the display unit 50 to output the image control signal Thereby realizing image display of real-time image information.

On the other hand, the preset data of the storage unit 30 may include preset mode data for a mode for switching the optical switch. That is, the balancing detecting optical coherence imaging apparatus 10 of the present invention may further include an input unit 60, and an input signal including a user's intention through the input unit 60 may be input by the user, When a preset mode through preset preset mode data in the storage unit 30 can be displayed on the display unit 50 and a selection is made through the input unit 60 by the user, And the control unit 20 controls the balancing optical switch 310 of the sensing unit 400 and the balancing switch unit 300 implemented by the galvanometer and the image of the desired region of the subject Information may be acquired and displayed on the display unit 50. [

In the meantime, although the balancing detecting optical coherence imaging apparatus of the present invention has been described as an integrated apparatus in the foregoing embodiments, the balancing detecting optical coherence imaging apparatus of the present invention may be embodied as a hand-held type probe, And is apparent from the present invention.

Such a structure can eliminate the complicated spectroscopic unit structure and achieve a simple and compact structure. This can improve the realization of the image-capturing device which is mated with the handheld type described above, Information acquisition system, Doppler optical coherence tomography algorithm can be applied to acquire information on the vascular structure, blood flow direction and velocity in tissue. In addition to acquiring images of the vascular structure using the same system configuration, it is also possible to calculate the phase change of the light according to the flow of blood and to obtain information about the direction and speed of blood flow in the software. Or may be implemented by various image information acquisition devices within a range that takes a predetermined configuration.

In the meantime, the main optical distributor 120 of the present invention is not limited to the embodiment of FIG. 1 but may include a single balancing optical distributor to reduce the cost of equipment. The same reference numerals and names are used for the same reference numerals, and redundant descriptions are omitted and differences are mainly described.

A variation of one embodiment of the present invention is shown in FIG. 2, where the master optical splitter 120 of the present invention can have a single number of balancing optical splitters, wherein the balancing optical splitter is formed of a first balancing optical splitter 121 . In this case, the first balancing optical splitter 121 divides the light received from the light source unit 100 by the optical fiber connected to the light source unit 100 side to advance to the interferometer 201 of the interference unit 200, And transmits the received signal to the balancing switching unit 300.

The light generated from the light source unit 100 is distributed to the first balancing optical distributor 121 of the main optical distributor 120 so that the sample arm 220 and the reference arm 230 of the interferometer 201, 202 and the sample arm of the common sample arm 202 and the interferometer 201 and the light reflected from the reference arm to the balancing switching unit 300 are the same as described above. 2 is provided with an optical circulator 110. The optical circulator 110 includes a light source unit 100 and a main optical distributor 120. The optical circulator 110 includes a light source 100, The first balancing optical splitter 121 and the first balancing optical splitter 121 are disposed between the light source unit 100 and the first balancing optical splitter 121 and are connected to the balancing optical switch 100. [ Lt; RTI ID = 0.0 > 310 < / RTI > The first balancing optical splitter 121 is connected to the balancing optical switch 310 of the light source unit 100 and the balancing switching unit 300 through the optical circulator 110 and simultaneously transmits the sample arm of the interferometer 201 220 and the reference arm 230 to allow transmission of light and return of the reflected light.

That is, the light emitted from the light source unit 100 is transmitted to the first balancing optical splitter 121 through the optical circulator 110, not to the balancing switching unit 300, and the first balancing optical splitter 121 receives the input And transmits the light to the sample arm 220 and the reference arm 230 of the interferometer 201. The light transmitted to the interferometer 201 and the interference unit 200 of the common sample arm 202 is returned to the first balancing optical splitter 121 via the inspected object S and the reference mirror 235.

The light transmitted to the first balancing optical splitter 121 is formed as an interference phenomenon, and the interference signals are respectively divided and transmitted from the first balancing optical splitter 121 to the balancing switching unit 300, Is the same as that of the above embodiment. When the light input from the light source unit 100 to the first balancing optical splitter 121 of the main optical distributor 120 through the optical circulator 110 is redistributed and transmitted to the interferometer 201 A phase difference of? / 2 is formed between the divided lights, and after the interference signal is formed again from the interferometer 201 to the first balancing optical splitter 121, the interference signal is redistributed and transmitted, And finally a phase difference of π is formed between the lights that are distributed and transmitted to the balancing switching unit 300. Such a configuration can minimize the possibility of image degradation by minimizing the optical element.

In the meantime, although the balancing detecting optical coherence imaging apparatus that implements the image information obtaining function for a single number of focus areas has been described, the balancing detecting optical coherence imaging apparatus of the present invention is capable of detecting image information for different focus areas It is possible to adopt a configuration capable of selective acquisition or substantially simultaneous acquisition. In this respect, the same reference numerals and names are used for the same components as in the foregoing embodiments, and the description of the difference between the interferometers will be omitted.

FIG. 3 is a schematic block diagram of a balanced detection optical coherence imaging apparatus that enables acquisition of image information for different focus regions according to another embodiment of the present invention.

The first balancing optical splitter 121 of the main optical distributor 120 divides the light of the wide band transmitted from the light source 100 and transmits the divided light to the sample arm 220 and the reference arm 230 of the interferometer 201.

The sample arm 220 has a sample arm collimator 223 which is connected to the first balancing optical splitter 121 side through the sample arm optical fiber 221 and more specifically to the first balancing optical splitter 121 121 are connected to an optical circulator 112 to form parallel light from the light source unit 100 through the first balancing optical splitter 121 and transmitted to the optical circulator 112, The light formed by the parallel light is irradiated from the sample arm collimator 223 to the focus region of the subject S through the common sample arm 202 described below.

The other one of the lights split from the light source unit 100 through the first balancing optical splitter 121 is transmitted to the reference arm 230 through the optical circulator 113. The reference arm 230 includes a reference optical switch A reference mirror 234, first and second reference arm collimators 232a, b, and first and second reference mirrors 235a, b. The reference optical switch 234 is connected to the first balancing optical splitter 121 and the optical circulator 113 via the reference arm optical fiber 231 and is switched according to the switching control signal of the control unit 20, The second reference arm collimator 233a and the second reference arm collimator 233b. The first reference arm collimator 233a and the second reference arm collimator 233b are connected to the reference optical switch 234 via the reference arm optical fiber 231. [ Through the structure of the reference arm optical fiber 231, the first and second reference arm collimators 233a and 233b and the first and second reference mirrors 235a and 23b, that is, the respective first reference arms 230a And the second reference arm 230b can be smoothly formed. In order to reduce the influence of the light intensity of the light due to the reference arm optical fiber 231, the optical circulator 113 A reference polarization adjuster 236a, b may be disposed between the reference optical switch 234 and / or the reference optical switch 234 and the first and second reference arm collimators 233a, b. The reference polarization controllers 236a and 236b may be configured to maximize the light intensity of the broadband light from the light source unit and shape the light to be close to Gaussian.

The first and second reference arm collimators 233ab are configured to emit parallel light in the same wavelength band as the sample collimator 231 described above. The collimated light emitted from the first and the reference arm collimators 233a and 233b is irradiated to the first and second reference mirrors 235a and 235b. The illuminated light is reflected by the first and second reference mirrors 235a and 235b and returned to the reference optical switch 234 through the first and second reference arm collimators 233a and 233b.

The light reflected by the first reference mirror 235a and transmitted to the second balancing optical distributor 123 via the reference optical switch 234 passes through the sample arm 202 to be transmitted through the sample arm 220, The light is incident on the first focus region of the subject reflected from the specimen S and transmitted to the second balancing optical splitter 123 to form an interference phenomenon to thereby acquire images of the first focus region P1 of the subject Thereby forming an interference signal.

The light reflected by the second reference mirror 235b and transmitted to the second balancing optical splitter 123 via the reference optical switch 234 passes through the common sample arm 202 through the sample arm 220, The second balanced light P2 is reflected by the second reflected light S and transmitted to the second balanced light distributor 123. The second focused area P2 is formed by interference with the light of the second focused area P2 of the inspected object, And an interference signal for image acquisition is formed.

The common sample arm 202 includes a common arm optical scanner 204 and a common arm objective lens 205. The common-arm optical scanner 204 transmits the light transmitted through the sample arm collimator 223 to the common-arm objective lens 205. The common-arm optical scanner 204 can be implemented as a galvanometer type, which is a mirror-mounted structure on a galvanometer and pivots at a predetermined angle and speed. Light passing through the common-arm optical scanner 204 is irradiated to the subject S, more specifically, the focus areas P1 and P2 of the subject S via the common-arm objective lens 205. [ The common-arm objective lens 205 includes two common-arm first objective lenses 205-1 and a common-arm second objective 205-2 in this embodiment. The number and type of common-arm objective lenses The present invention is not limited to this, and various configurations are possible depending on the relationship between the design specification and the focus region of the subject to be measured.

The light of the wide band distributed through the first interferometer 201a and the second interferometer 201b of the interference unit 200 through the main optical distributor 120 is transmitted to each of the first optical splitter 210a, The second sample arm 220b and the first reference arm 230a / the second reference arm 230b via the second optical distributor / second optical splitter 210b. Light passing through the first sample arm 220a and the second sample arm 220b is transmitted through the common sample arm 202 and irradiated to the respective focus regions P1 and P2 of the inspected object P. [ Then, the reflected light, which allows the image signals for the respective focus areas P1 and P2 to be acquired, is reflected by the common sample arm 202 and the first sample arm 220a / The first optical splitter 210a and the second optical splitter 210b are distributed to the first optical splitter 210a and the second optical splitter 210b via the first optical splitter 220a and the second optical splitter 210b, The light transmitted to the reference arm 230a and the second reference arm 230b is reflected by the first reference mirror 235a and the second reference mirror 235b and passes through the first optical splitter 210a / 2 optical splitter 210b. The reflected light for image acquisition of the focus regions P1 and P2 of the inspected object S passing through the first sample arm 220a / the second sample arm 220b and the common sample arm 202, An interference signal is generated due to an interference phenomenon with light reflected from the first reference mirror 235a / second reference mirror 235b through the first reference arm 230a / the second reference arm 230b.

The first reference arm 230a and the second reference arm 230b have the same structure and the first reference arm 230a is formed between the first reference arm collimator 233a and the first reference mirror 235a And the second reference arm 230b has a second reference optical pathRas formed between the second reference arm collimator 233b and the second reference mirror 235b do. The first reference mirror 235a may be further provided with a first reference mirror 235a and a second reference mirror 235b. The first reference mirror 235a may include a first reference mirror 235a and a second reference mirror 235b. And a second reference mirror 235b that reflects the light input from the second reference arm collimator 233a through the common reference light distributors 241 and 243. The second reference mirror 235b receives the common reference light from the second reference arm collimator 233b, And a dispersed second reference optical path mirror 235b that reflects and transmits the light input through the optical distributors 241 and 243.

3, the first reference light path is between the first reference arm collimator 233a and the first reference mirror 235a, and the second reference light path is between the second reference arm collimator 233b and the second reference light path 233b. 2 reference mirror 235b between the first reference arm collimator 233a and the first reference mirror 235a and between the second reference arm collimator 233b and the second reference mirror 235b between the first reference arm collimator 233a and the first reference mirror 235a, On the reference optical path and the second reference optical path, common reference optical splitters 241 and 243, through which the respective lights pass, are disposed. The common reference light distributors 241 and 243 correspond to the first distributed optical distributor 2061 of the common-arm optical distributor 203 and the common-arm optical path distributor 206, respectively.

Two common reference optical distributors 241 and 243 are provided. The common reference light distributor 241 indicated by reference numeral 241 divides the light transmitted from the first reference arm collimator 233a / the second reference arm collimator 233b into The common reference light distributor 243 divides the received light into the first reference mirror 235a and the second reference mirror 235a, That is, the scattered first reference light path mirror 235a and the second reference mirror, that is, the scattered second reference light path mirror 235b. On the other hand, the light reflected by the first reference mirror 235a and the second reference mirror 235b travels along the reverse path, and the light transmitted to the common reference light splitter 243 indicated by reference numeral 243 is collected, The reflected light is transmitted to the common reference light distributor 241 indicated by the reference numeral 241 and the reflected light inputted to the common reference light distributor 241 passes through each of the first reference arm collimator 233a and the second reference arm collimator 233b, And is transmitted to the optical switch 234. In this case, a common reference lens may be further included between the common reference light distributors 241 and 243, which may be formed of an achromatic lens, As a ND filter (Neutral Density filter) for adjusting the amount of light is provided between the common reference light distributor 243 and the second reference mirror, that is, the dispersed second reference arm optical path mirror 235b, A reference light path filter 247b may be further provided, and various configurations are possible according to design specifications.

Here, the common reference light splitters 241 and 243 are implemented as a polarized beam splitter (PBS), and the lights forming the first reference light path and the second reference light path via the common reference light distributing paths 241 and 243, respectively, Is selectively formed so as to match with the polarized structure in the common sample arm which is alternatively selected so as not to be overlapped among the horizontal light (LP) and the vertical light (LS).

That is, in this embodiment, the light on the first reference light path is formed of the normal light (LP) and the light on the second reference light path is formed of the perpendicular light (LS) Taking the structure excluded on the optical path. It is apparent from the above that it is possible to take an opposite structure as an example.

The light transmitted and received from the first reference arm collimator 233a to the common reference light splitter 241 indicated by reference numeral 241 is transmitted to the common reference light splitter 241 and is transmitted from the first reference arm collimator 233a Of the light input to the reference optical distributor 241, only the LP component is transmitted and transmitted through the common reference optical distributor 243 indicated by reference numeral 243, transmitted to and reflected by the first reference mirror 235a, 1 reference collimator 233a to the reference optical switch 234 and interference with light reflected from the sample arm side occurs. Namely, only the normal light (LP) component can be used by appropriately adjusting the common reference light distributors 241 and 243 on the first reference optical path.

The light transmitted and received from the second reference arm collimator 233b to the common reference light splitter 241 is transmitted to the common reference light splitter 241 and the second reference arm collimator 233b, (LS) component of the light input to the common reference light splitter 241 is transmitted and reflected by the second reference mirror 235b through the common reference light splitter 243 indicated by reference numeral 243, And then transmitted through the second reference arm collimator 233b to the reference optical switch 234 and interference with the light reflected from the sample arm side occurs. Namely, only the vertical light (LS) component can be used by appropriately adjusting the common reference light distributors 241 and 243 on the second reference light path.

The common sample arm 202 includes a common arm optical scanner 204 and a common arm optical path distribution unit 206. The light transmitted through the sample arm collimator 223 is transmitted to the common arm optical scanner 204. The common-arm optical scanner 204 can be implemented as a galvanometer type, which is a mirror-mounted structure on a galvanometer and pivots at a predetermined angle and speed. The light passing through the common arm optical scanner 204 is irradiated to the subject S and more specifically to the focus areas P1 and P2 of the subject S via the common arm light path dispersing unit 206. [ The light input to the common-arm optical path distributor 206 forms a different optical path, i.e., a first sample optical path and a second sample optical path, depending on whether polarized light is a normal light component or a normal light component. In the drawing, each is represented by a dotted line denoted by PathP and PathS. The horizontal light component LP constituting the first sample optical path PathP is divided into a dispersive first optical distributor 2061, which is implemented by PBS, The vertical light component LS that is transmitted through the optical splitter 2062 and constitutes the second sample optical path PathS is reflected and transmitted to the optical path in the dispersion first optical splitter 2061 and the dispersion second optical splitter 2062 Structure.

More specifically, the common-arm optical path distributing section 206 includes a dispersion-type first optical distributor 2061, a dispersion-type second optical distributor 2062, a dispersion objective lens 2069, 2065, and 2067), and a dispersed second sample optical path focusing lens 2063. The dispersed first optical distributor 2061 and the dispersed second optical distributor 2062 are implemented as a PBS as described above. The dispersion-type first optical distributor 2061 and the dispersion-type second optical distributor 2062 form different optical paths according to the polarization components of light. That is, an optical path is determined depending on whether the light passed through the common arm optical scanner 204 is a normal light component LP or a vertical light component LS. The dispersive first optical distributor 2061 separates the optical scanner 204, (PathP) formed in the same direction as the traveling direction of the light irradiated from the optical scanner and the second sample optical path PathP formed in the direction perpendicular to the traveling direction of the light irradiated from the optical scanner 204 And a second sample optical path (Path S) is formed. The dispersed second optical distributor 2062 is disposed between the dispersed first optical distributor 2061 and the object to be inspected and disposed on the first sample optical path PathP and the second sample optical path PathS, The first sample optical path PathP and the second sample optical path PathS pass both the dispersion first and second optical splitters 2061 and 2062. [

The dispersed second sample optical path mirrors 2065 and 2067 are disposed on the second sample optical path PathS so that the light split by the first dispersive optical distributor 2061 is combined by the second dispersive optical distributor 2062 2 sample optical paths (PathS). When the light is reflected from the object and travels in the opposite direction, the dispersed second sample optical path mirrors 2065 and 2067 can transmit the reflected vertical light component branched at the dispersed second optical distributor to the dispersed first optical distributor. The second sample optical path PathS is formed to be different from the first sample optical path PathP. In this embodiment, two dispersed second sample optical path mirrors 2065 and 2067 are provided, The present invention is not limited to the number of mirrors.

The dispersive objective lens 2069 is disposed between the dispersed second optical distributor 2062 and the inspected object S and transmits light transmitted through or reflected and transmitted through the dispersed second optical distributor 2062 to a different And the light reflected from the different focus regions P1 and P2 of the subject S is transmitted to the second dispersion optical splitter 2062 again.

The dispersed second sample optical path focus lens 2063 is disposed on the second sample optical path PathP between the dispersive first optical distributor 2061 and the dispersed second sample optical path mirror 2065, Since the exemplary dispersive objective lens 2069 is disposed between the subject S and the dispersed second optical distributor 2061, light is transmitted through the dispersed second sample optical path focusing lens 2063 to the second focus region P2 So that it is precisely focused. That is, in this embodiment, the dispersion objective lens 2069 is disposed on the first sample optical path PathP and the second sample optical path PathS. For example, when the inspected object S is an eye, The light on the first sample optical path PathP through the dispersion objective lens 2069 is focused on the first focus region P1 that is the cornea, The second sample optical path PathS passed through the lens 2063 is converted to parallel light by passing through the dispersion objective lens 2069 and is irradiated to the eye as the subject S and the lens of the eyeball serves as a separate lens So that the vertical light component of the second sample optical path PathS can be accurately focused on the retina which is the second focus position Ps of the subject S to acquire a predetermined accurate imaging image.

That is, a signal having passed through the first sample arm collimator 223a through the common-arm optical path dispersing unit 206 is transmitted to the dispersive first and second optical distributors 2061 and 2062 along the first sample optical path PathP, Transmitted through the dispersion objective lens 2069 to the first focus region P1 of the inspected object S and then reflected and transmitted along the reverse path to the first sample arm collimator 223a, And the second balanced optical splitter 123 to form an interference signal together with the optical signal reflected from the first reference arm side.

The signal passed through the second sample arm collimator 223b is reflected and transmitted along the second sample optical path PathS through the dispersive first optical splitter 2061 to be transmitted through the dispersed second sample optical path focusing lens 2063 and dispersion Is transmitted through the second sample optical path mirrors 2065 and 2067 to the dispersion second optical distributor 2062 and reflected and transmitted by the dispersion second optical distributor 2062 and is transmitted to the sample S via the dispersion objective lens 2069 Parallel light is input through the dispersed second sample optical path focusing lens 2063 and the dispersion objective lens 2069 and is transmitted through the lens of the eye to be examined S to the retina which is the second focus region P2 The reflected light is further reflected and transmitted to the second sample arm collimator 223b along the reverse path to be transmitted to the optical circulator and the second balancing optical splitter to form an interference signal together with the optical signal reflected from the second reference arm side .

Each of the different focus areas P1 and P2 of the inspected object S is projected through the interferometer 210 having the common sample arm 202, the reference arm and the sample arm of the interference unit having the common- It is possible to form a signal for forming an interference signal for forming more accurate image information with respect to the signal.

The subject S according to the present embodiment may be an eyeball as in the previous embodiment and the focus areas P1 and P2 may be designated as cornea and cornea and retina respectively And the image information to be acquired is the same as that described in the foregoing embodiment in addition to the point that the image quality is improved.

The balancing detecting optical coherence imaging apparatus of the present invention can acquire information on the vascular structure, blood flow direction and velocity in the tissue by applying the Doppler optical coherence tomography algorithm in addition to the ocular imaging information acquisition apparatus. In addition to acquiring images of the vascular structure using the same system configuration, it is also possible to calculate the phase change of the light according to the flow of blood and to obtain information about the direction and speed of blood flow in the software. Or may be implemented by various image information acquisition devices within a range that takes a predetermined configuration.

The rest of the configuration is the same as the configuration mentioned in the embodiment of FIG.

On the other hand, the present invention may be configured to acquire image information for different focus areas and to have the same configuration as that of the embodiment of FIG. 2 for simplicity of components. That is, FIG. 4 shows a schematic view of a balanced detection optical coherence imaging apparatus capable of acquiring image information for different focus regions according to another embodiment of the present invention and the main optical distributor having a single number of balancing optical splitters A block diagram is shown. Here, the interferometer 201 of the interference unit may include a reference arm 230 and a sample arm 220 having the same reference switch 234 as in the case of FIG. 3, and the main optical distributor 120 may include a single- The optical circulator 110 includes a balancing optical splitter 121 and a balancing switching unit 300 and a detection unit 400. The optical circulator 110 is disposed between the light source unit 100 and the interferometer 201 of the interference unit 200, And the optical circulator 110 is connected to the balancing optical splitter 121 and one side of the balancing switching unit 300 is the same as that in FIG. 3 in the previous embodiment.

The embodiments are illustrative of the present invention, and the present invention is not limited thereto, and various modifications are possible.

10 ... Balancing Detecting Optical Coherence Imager 20 ... Control
30 ... storage unit 40 ... operation unit
50 ... display unit 100 ... light source unit
200 ... interference unit 300 ... balancing switching unit
400 ... Detection unit

Claims (24)

A light source unit (100) for generating light in a wide band;
A main optical distributor (120) including at least one balancing optical distributor for distributing and propagating light generated from the light source unit;
An interference unit 201 for forming an interference signal for at least one focus region of the subject using the light distributed from the main optical distributor, and an interference unit 201, which is commonly connected to the interference unit, A common sample arm (203) for forming optical path differences with respect to at least one focus region of the specimen; and a balancing unit for alternately switching and outputting an interference signal formed and distributed through at least a part of the main optical distributor An interference unit 200 having a switching unit 300;
And a detection unit (400) for converting the interference signal output from the balancing switching unit into an electrical signal. The method according to claim 1,
The balancing switching unit 300 includes:
A balancing optical switch 310 for receiving an interference signal distributed from at least a part of the main optical distributor and alternately outputting the interference signal to the detection unit,
A balancing delay unit 320 disposed in one of two optical paths between at least a part of the main optical distributor and the balancing optical switch for delaying the transmission of an interference signal transmitted from the main optical distributor to the balancing optical switch, Wherein the balanced coherent detector is a coherent detector. 3. The method of claim 2,
Wherein the balancing delay unit (320) is an optical fiber having a predetermined length. 3. The method of claim 2,
The main optical distributor 120 includes:
A first balancing optical splitter 121 for distributing and propagating the light received from the light source unit,
And a second balancing optical splitter (123) for receiving the signal transmitted from the interference unit, forming the interference signal, redistributing the signal, and outputting the interference signal. 5. The method of claim 4,
The interferometer 201 comprises:
A sample arm 220 having a sample arm collimator for receiving light distributed from the main optical distributor,
A reference optical switch 234 that receives light distributed from the main optical distributor other than the light that is distributed to the sample arm and alternately switches in a predetermined manner; a first reference switch 234 that receives light alternately from the reference optical switch, The first reference arm collimator, the second reference arm collimator, the first reference arm collimator, and the second reference arm collimator, and reflects the light transmitted from the first reference arm collimator and the second reference arm collimator to return to the first reference arm collimator and the second reference arm collimator, And a reference arm (230) including a first reference arm (230a) and a second reference arm (230b) each including a first reference mirror and a second reference mirror. 6. The method of claim 5,
The common sample arm is:
A common arm optical scanner 204 for irradiating light transmitted through the sample arm collimator toward different focus areas of the subject,
Irradiating the light irradiated from the common arm optical scanner to different focus areas of the subject and transmitting the light reflected from different focus areas of the subject to the common arm optical scanner again, And a common-arm optical path dispersion unit (206) disposed between the subject and the common-arm optical scanner so as to form a light path difference of light to be irradiated on the subject. The method according to claim 6,
The common-arm optical path dispersion unit 206 includes:
A first sample optical path PathP formed in the same direction as the traveling direction of the light irradiated from the optical scanner, and a second optical path path Sd perpendicular to the traveling direction of the light irradiated from the optical scanner A first dispersive optical distributor 2061 for forming a second sample optical path PathS formed by the first optical splitter 2061,
A dispersed second optical splitter 2062 disposed between the inspected objects facing the dispersed first optical splitter and disposed on the first sample optical path PathP and the second sample optical path PathS,
And a second optical distributor (2062) disposed between the dispersed second optical distributor (2062) and the subject to irradiate different focus areas of the inspected object with light transmitted through the dispersed second optical distributor (2062) A dispersive objective lens 2069 for transmitting the light reflected from the region to the second dispersive optical distributor 2062,
Scattered second sample optical path mirrors 2065 and 2067 arranged on the second sample optical path PathS to form the second sample optical path PathS different from the first sample optical path PathP, ,
And a dispersed second sample optical path focusing lens (2063) disposed on an optical path that does not intersect with the first sample optical path PathP of the second sample optical path (PathS) Optical coherence imaging device. 8. The method of claim 7,
Wherein said dispersed second sample optical path focusing lens (2063) is disposed between said dispersed first optical distributor (2061) and said dispersed second sample optical path mirror (2065) . 6. The method of claim 5,
The first reference arm 230a has a first reference optical pathRP formed between the first reference arm collimator 233a and the first reference mirror 235a,
The second reference arm 230b includes a second reference optical path RS formed between the second reference arm collimator 233b and the second reference mirror 235b,
And a common reference optical splitter (241, 243) through which light on the first reference optical path (PathRP) and the light on the second reference optical path (Path RS) pass. 10. The method of claim 9,
The first reference mirror of the first reference arm 230a is a distributed first reference light path mirror 235a that reflects and transmits the light inputted through the common reference light distributors 241 and 243,
And the second reference mirror of the second reference arm 230b is a dispersed second reference optical path mirror 235b that reflects and transmits the light input through the common reference light distributors 241 and 243. [ Tessing Optical Coherence Imaging. 10. The method of claim 9,
A first reference polarization controller 236a and a second reference polarization controller 236b are provided between the reference optical switch 234 and the first reference arm collimator 233a and the second reference arm collimator 233b Wherein the optical coherence detector is a balancing detector. 6. The method of claim 5,
Optical circulators 110 and 111 and 113 are disposed in the first balancing optical splitter 121 and the second balancing optical splitter 123,
The optical circulator 110 is connected to the sample arm 220 and the reference arm 230 so that light transmitted from the first balancing optical splitter 121 is transmitted to the sample arm 220 and the reference arm 230, And transmits the reflected light from the sample arm 220 and the reference arm 230 to the second balancing optical distributor 123. The balanced coherent optical coherence image Device. 3. The method of claim 2,
The balancing optical divider of the main optical distributor 120 includes:
And a first balancing optical distributor (121) for distributing the light received from the light source part and advancing the light to at least a part of the interferometer, and for receiving the signal reflected from the interferometer and advancing it to another part of the interferometer. Optical coherence imaging device. 14. The method of claim 13,
The interferometer comprising:
A sample arm 220 having a sample arm collimator 223 for receiving light distributed from the main optical distributor,
A reference optical switch 234 that receives light distributed from the main optical distributor 120 and is alternately switched in a preset manner other than light distributed to the sample arm 220, Reflects light transmitted from the first reference arm collimator 233a and the second reference arm collimator 233b, the first reference arm collimator 233a, and the second reference arm collimator 233b, A first reference arm 230a including a first reference mirror 235a and a second reference mirror 235b for returning to the first reference arm collimator 233a and the second reference arm collimator 233b, And a reference arm (230) including an arm (230b). 15. The method of claim 14,
The common sample arm 202 includes:
A common arm optical scanner 204 for irradiating light transmitted through the sample arm collimator toward different focus areas of the subject,
Irradiating the light irradiated from the common arm optical scanner to different focus areas of the subject and transmitting the light reflected from different focus areas of the subject to the common arm optical scanner again, And a common-arm optical path dispersion unit (206) disposed between the subject and the common-arm optical scanner so as to form a light path difference of light to be irradiated on the subject. 16. The method of claim 15,
The common-arm optical path dispersion unit 206 includes:
A first sample optical path PathP formed in the same direction as the traveling direction of the light irradiated from the optical scanner, and a second optical path path Sd perpendicular to the traveling direction of the light irradiated from the optical scanner A first dispersive optical distributor 2061 for forming a second sample optical path PathS formed by the first optical splitter 2061,
A dispersed second optical splitter 2062 disposed between the inspected objects facing the dispersed first optical splitter and disposed on the first sample optical path PathP and the second sample optical path PathS,
And a second optical distributor (2062) disposed between the dispersed second optical distributor (2062) and the subject to irradiate different focus areas of the inspected object with light transmitted through the dispersed second optical distributor (2062) A dispersive objective lens 2069 for transmitting the light reflected from the region to the second dispersive optical distributor 2062,
Scattered second sample optical path mirrors 2065 and 2067 arranged on the second sample optical path PathS to form the second sample optical path PathS different from the first sample optical path PathP, ,
And a dispersed second sample optical path focusing lens (2063) disposed on an optical path that does not intersect with the first sample optical path PathP of the second sample optical path (PathS) Optical coherence imaging device. 17. The method of claim 16,
Wherein said dispersed second sample optical path focusing lens (2063) is disposed between said dispersed first optical distributor (2061) and said dispersed second sample optical path mirror (2065) . 15. The method of claim 14,
The first reference arm 230a has a first reference optical pathRP formed between the first reference arm collimator 233a and the first reference mirror 235a,
The second reference arm 230b includes a second reference optical path RS formed between the second reference arm collimator 233b and the second reference mirror 235b,
And a common reference optical splitter (241, 243) through which light on the first reference optical path (PathRP) and the light on the second reference optical path (Path RS) pass. 19. The method of claim 18,
The first reference mirror of the first reference arm 230a is a distributed first reference light path mirror 235a that reflects and transmits the light inputted through the common reference light distributors 241 and 243,
And the second reference mirror of the second reference arm 230b is a dispersed second reference optical path mirror 235b that reflects and transmits the light input through the common reference light distributors 241 and 243. [ Tessing Optical Coherence Imaging. 19. The method of claim 18,
A first reference polarization controller 236a and a second reference polarization controller 236b are provided between the reference optical switch 234 and the first reference arm collimator 233a and the second reference arm collimator 233b Wherein the optical coherence detector is a balancing detector. 15. The method of claim 14,
The light source unit and the optical circulator of the first balancing optical splitter are disposed,
Wherein the optical circulator is connected to the balancing switching unit to transmit light emitted from the light source unit to the first balancing optical splitter and to transmit the light transmitted from the first balancing optical splitter to the balancing switching unit Balancing detection optical coherence imaging device.
The method according to claim 1,
Wherein the detection unit comprises:
A detection collimator for outputting the interference signal selected by the balancing switching unit as parallel light;
A detection diffraction grating for diffracting light incident from the detection collimator,
A detection lens that focuses the light diffracted by the detection diffraction grating,
And a detector for converting the diffracted light incident on the focus lens into an electrical signal from the detection lens. The method according to claim 1,
Wherein at least one of the main optical distributors comprises an optical fiber splitter. The method according to claim 1,
A control unit for receiving an electrical signal from the detection unit,
A storage unit connected to the control unit and storing preset data;
An arithmetic unit for performing arithmetic operation according to a control signal of the control unit and calculating image information based on an electrical signal transmitted from the detection unit and preset data of the storage unit;
And a display unit for displaying the image information according to an image control signal of the control unit.

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