KR102346342B1 - MEMS mirror control apparatus and method for optical coherence tomography system - Google Patents

Abstract

The present invention relates to an apparatus for controlling a MEMS mirror for an optical coherence tomography imaging system and a method for controlling the same, and more particularly, to an apparatus for controlling an operation of a MEMS mirror performing 2D or 3D scanning of an object in an optical coherence tomography imaging system and to a method for controlling the same.
According to the present invention, when implementing a sawtooth wave signal as a MEMS mirror scan control signal, it is not a method that cuts off the signal at a specific time using a timer interrupt method as in the past, but a Fourier series of a periodic function and scan A MEMS mirror control device and its control method are provided that realize a signal, but generate the best image without mirror shake and no sagging by finding the Fourier series for the optimal n value in which the mirror shake phenomenon disappears and using it as a scan signal. .

Description

MEMS mirror control apparatus and method for optical coherence tomography system and method for controlling the same for optical coherence tomography system

The present invention relates to an apparatus for controlling a MEMS mirror for an optical coherence tomography imaging system and a method for controlling the same, and more particularly, to an apparatus for controlling an operation of a MEMS mirror performing 2D or 3D scanning of an object in an optical interference tomography imaging system and to a method for controlling the same.

In the optical coherence tomography system, a 2-axis scanning mirror is used to perform 2D or 3D scanning of an object. In addition, the size of the driving unit that drives the mirror had to be increased as well. The 2-axis MEMS mirror has the advantage of greatly reducing the volume because one mirror rotates in two axes, so the problem could be solved.

In controlling such a 2-axis MEMS mirror, sawtooth is used as the MEMS scan control signal. In a conventional 32-bit microcontroller, SOC (System On Chip), a timer interrupt method is used to control the MEMS mirror for a specific time. By cutting off the signal, such a sawtooth wave was realized to control the scan.

However, when the scan is controlled using the sawtooth wave implemented in such a way, the MEMS mirror vibrates nonlinearly in the section where the signal is sharply bent. There was a problem that was the biggest cause of serious errors when image processing was performed.

KR 10-2014-0097727 A

The present invention was devised to solve this problem, and when a sawtooth wave signal as a MEMS mirror scan control signal is implemented, it is not a method that cuts off a signal at a specific time using a timer interrupt method as in the conventional one, but a periodic function A MEMS mirror that realizes a scan signal by finding a Fourier series, but finds a Fourier series for the optimal n value where the mirror shake phenomenon disappears and uses it as a scan signal to generate the best image without mirror shake and sagging An object of the present invention is to provide a control device and a control method therefor.

에 의하여 구해지고,
여기서

,

,

이고,

,

이다.MEMS mirror control apparatus according to the present invention in order to achieve the above object, a communication interface conversion unit for performing a communication interface conversion between the control and image acquisition device and the control signal generator; a control signal generator for generating a MEMS mirror scan control signal; and a D/A converter for converting the MEMS mirror scan control signal formed by the control signal generator into a low-voltage analog scan control signal, wherein the control signal generator includes a MEMS mirror scan control signal by calculating a Fourier series The Fourier series calculation of the control signal generating unit is performed so that, when the MEMS mirror is scanned, shaking at both ends of the scan is removed,

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The MEMS mirror control device may further include a high voltage amplifier for amplifying the low voltage analog scan control signal output from the D/A converter into a high voltage analog scan control signal.

The MEMS mirror control device may further include a high voltage converter that converts the low voltage power supplied from the control and image acquisition device into a high voltage and provides the converted low voltage power to the high voltage amplifier.

delete

The control signal generator may further include a function of generating a line scan camera trigger signal and transmitting the generated line scan camera trigger signal to the line scan camera.

에 의하여 구해지고,
여기서

,

,

이고,

,

이다.According to another aspect of the present invention, there is provided a method for the control signal generating unit to control the MEMS mirror, comprising the steps of: (a) receiving a MEMS mirror control parameter from a control and image acquisition device; (b) setting the parameter as a control parameter for forming a MEMS mirror scan control signal; (c) receiving a scan command of the MEMS mirror from the control and image acquisition device; and, (d) forming a MEMS mirror scan control signal according to the scan command, wherein the MEMS mirror scan control signal in step (d) is formed by an operation of a Fourier series, wherein the Fourier series operation comprises: , so that the vibration at both ends of the scan is removed when scanning the MEMS mirror,

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The scan command in step (c) may be a 2D scan command or a 3D scan command.

When the scan command of step (c) is a 2D scan command, the MEMS mirror scan control signal of step (d) may be an x-axis scan control signal.

After the step (d), (e) receiving a 3D scan command of the MEMS mirror from the control and image acquisition device; and, (f) forming a y-axis scan control signal of the MEMS mirror according to the scan command.

delete

Prior to the step (c), (c01) receiving a line scan camera trigger signal control parameter from the control and image acquisition device; and, (c02) setting the parameter as a control parameter for forming a line scan camera trigger signal; The method may further include forming a trigger signal and transmitting it to the line scan camera.

에 의하여 구해지고,
여기서

,

,

이고,

,

이다.According to another aspect of the present invention, the computer program stored in the non-transitory storage medium for the control signal generating unit to perform MEMS mirror control is stored in the non-transitory storage medium, and by the processor, (a) control and image receiving the MEMS mirror control parameter from the acquiring device; (b) setting the parameter as a control parameter for forming a MEMS mirror scan control signal; (c) receiving a scan command of the MEMS mirror from the control and image acquisition device; and, (d) generating a MEMS mirror scan control signal according to the scan command to be executed, wherein the MEMS mirror scan control signal in step (d) is formed by an operation of a Fourier series, The Fourier series calculation is such that, when scanning the MEMS mirror, vibrations at both ends of the scan are removed,

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According to another aspect of the present invention, there is provided a method for a control and image acquisition apparatus to control the MEMS mirror apparatus, the method comprising: (a) receiving a MEMS mirror control parameter; (b) transmitting the MEMS mirror control parameters to the MEMS mirror control device; (c) receiving a MEMS mirror scan input; and, (d) transmitting a scan command of the MEMS mirror to the MEMS mirror control device.

The scan in steps (c) and (d) may be a 2D scan or a 3D scan.

When the scans of steps (c) and (d) are 2D scans, after step (d), (e) receiving a MEMS mirror 3D scan; and, (f) transmitting a 3D scan command of the MEMS mirror to the MEMS mirror control device.

Prior to step (c), (c01) receiving a line scan camera trigger signal control parameter; and, (c02) transmitting the line scan camera trigger signal control parameter to the MEMS mirror control device.

According to another aspect of the present invention, a computer program stored in a non-transitory storage medium for the control and image acquisition device to control the MEMS mirror device is stored in the non-transitory storage medium, and by the processor, ( a) receiving MEMS mirror control parameters; (b) transmitting the MEMS mirror control parameters to the MEMS mirror control device; (c) receiving a MEMS mirror scan input; and, (d) sending a scan command of the MEMS mirror to the MEMS mirror control device to be executed.

According to the present invention, when implementing a sawtooth wave signal as a MEMS mirror scan control signal, it is not a method that cuts off the signal at a specific time using a timer interrupt method as in the past, but a Fourier series of a periodic function and scan To provide a MEMS mirror control device and its control method that implement a signal, but obtain the Fourier series for the optimal n value in which the mirror shake phenomenon disappears, and use it as a scan signal to generate the best image without mirror shake and sagging. It works.

1 is a view showing an optical coherence tomography imaging system according to the present invention.
2 is a view for explaining a MEMS mirror scan control signal and its problems;
3 is a diagram illustrating a typical sawtooth wave signal.
4 is a diagram in which a sawtooth signal is implemented as a Fourier series in the case of n=5 and n=10.
5 is a diagram illustrating a trigger signal of a line scan camera;
6 is a flowchart illustrating a sequence for controlling a MEMS mirror control apparatus according to the present invention.
7 is a view showing the configuration of a MEMS mirror control apparatus according to the present invention.
8 is a flowchart illustrating a control sequence of a control signal generator in the MEMS mirror control apparatus according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms or words used in the present specification and claims should not be construed as being limited to conventional or dictionary meanings, and the inventor should properly understand the concept of the term in order to best describe his invention. Based on the principle that it can be defined, it should be interpreted as meaning and concept consistent with the technical idea of the present invention. Accordingly, the embodiments described in this specification and the configurations shown in the drawings are only the most preferred embodiment of the present invention and do not represent all the technical spirit of the present invention, so at the time of the present application, various It should be understood that there may be equivalents and variations.

1 is a diagram illustrating an optical coherence tomography imaging system according to the present invention.

The optical coherence tomography imaging system 1000 includes a light source unit 1100 , a coupler 1200 , a reference unit 1300 , a scan unit 1400 , and an optical coherence tomography image to obtain a tomographic image of the object 40 . It includes a capture unit 1500 and a MEMS mirror control unit 1600 .

Also, the optical coherence tomography imaging system 1000 may further include a surface image capture unit 1700 to acquire a surface image of the object 40 .

The control and image acquisition device 1800 implements a tomography image of the object by collecting the tomographic images of the object 40 captured by the optical coherence tomography image capture unit 1500 , and displays the implemented image on the display device 1810 . Also, by receiving the surface image of the object 40 captured by the surface image capture unit 1700 , the surface image is also displayed on the display device 1810 .

Furthermore, the control and image acquisition device 1800 controls the operation of the MEMS mirror control device 1600 to control the entire process for optical coherence tomography image acquisition.

Hereinafter, the operation of the optical coherence tomography imaging system 1000 will be described in more detail through the functions of each component.

In the light source unit 1100 , the first light source 1110 generates light having a wavelength of 840 nm. The isolator 1120 serves to block the reflected light from entering the first light source 1110 again after passing through the coupler 1200, thereby passing through the coupler 1200 and returning Light propagates only to the optical coherence tomography image capture unit 1500 .

The light irradiated from the first light source 1110 passes through the coupler 1200 and is divided into a reference unit 1300 and a scan unit 1400 and proceeds.

Light traveling in parallel through the collimator 1310 of the reference unit 1300 passes through the focusing lens 1320 , is reflected by the reference mirror 1330 , and enters the coupler 1200 again.

In addition, light passing through the collimator 1410 of the scan unit 1400 and traveling in parallel is reflected by the MEMS mirror 1420 . The MEMS mirror 1420 does not require two mirrors as one mirror rotates in two axes. That is, a tomography image of one surface can be acquired by scanning one x-axis line of the object 40 through rotation in one axis (x-axis), and rotation in the other one axis (y-axis) is performed. By scanning the other x-axis lines of the object 40 through the screen, the image obtained thereby enables the acquisition of a 3D tomography image. The beam splitter 1430 reflects the light reflected from the MEMS mirror 1420 again, so that the light is incident on the object 40 through the focusing lens 1440 . If the light of the first light source 1110 is light that can be transmitted up to, for example, 5 mm, when the MEMS mirror 1420 is at a point during the x-axis scan, the light is transmitted to a depth of 5 mm of the object 40, (40) The image from the surface of the corresponding point to a depth of 5 mm is reflected and enters the coupler 1200 again.

In this way, when the light reflected from the reference unit 1300 and the light reflected from the scan unit 1400 are combined in the coupler 1200, the distance between the focusing lens 1320 and the reference mirror 1330 and the focusing lens ( When the distance between 1440 ) and the object 40 is the same, an interference fringe is generated, and the interference fringe enters the optical coherence tomography image capture unit 1500 . As such, the interference image entering the optical coherence tomography image capture unit 1500 passes through the collimator 1520 and becomes parallel, and then is extended to a longer length in the grating unit 1530 and the lens arrangement 100 Passing through, the image is formed on the focal plane (focal plane) (10). The focal plane 10 may be a kind of line scan sensor. As described above, in the image formed on the line scan sensor 10 at a time, when the MEMS mirror 1420 is at a point during the x-axis scan, light is transmitted to a specific depth of the object 40 , and the object 40 ) becomes an image of one line from the surface of the corresponding point to the corresponding depth.

This one-line image is acquired by the control and image acquisition device 1800, and continuously, according to the x-axis scan of the MEMS mirror 1420, one-line images up to a specific depth at each point on the x-axis are continuously controlled and imaged. It is acquired by the acquisition device 1800 .

As a result, as a result, the control and image acquisition device 1800 acquires a tomographic image of one surface up to a specific depth with respect to the x-axis line of the object by summing the images of one line up to the corresponding depth and the specific depth of the object 40 . Furthermore, when tomography images of adjacent surfaces are continuously acquired as the MEMS mirror 1420 performs a y-axis scan, a 3D tomography image up to a specific depth of the object 40 may be acquired. Such a tomographic image is displayed through the display device 1810 .

The lens arrangement 100 of the optical coherence tomography image capture unit 1500 will be described later in detail with reference to FIGS. 8 to 11 .

On the other hand, the aforementioned beam splitter 1430 has, for example, a characteristic of reflecting light having a wavelength of 800 nm or more and transmitting light having a wavelength of less than 800 nm. Accordingly, as described above, light of a wavelength of 840 nm emitted from the first light source 1110 is reflected in the direction of the object 40 .

Referring to FIG. 1 , a second light source 50 for irradiating light with a wavelength of 400 to 630 nm toward the object 40 is provided on the object 40 . When this light is reflected from the surface of the object 40 and enters the beam splitter 1430, the reflected light, that is, the image of the surface of the object 40, is light with a wavelength of less than 800 nm, so it passes through the beam splitter 1430 and goes out. After passing through the lens array 200 for imaging, an image is captured on a focal plane 20, and the captured object 40 surface image is also acquired from the control and image acquisition device 1800 It is displayed through the display device 1810 .

As described above, the optical coherence tomography imaging system 1000 of the present invention simultaneously acquires a tomography image and a surface image of the object 40 and shows it to the user, thereby enabling the analysis of the object 40 to be performed more effectively.

The MEMS mirror control device 1600 also serves to generate a trigger signal for reading the image formed on the image forming device 10, 20, which is collectively referred to as the 'focal plane (10, 20)' from above.

The lens arrangement 200 of the surface image capture unit 1700 will be described later in detail with reference to FIGS. 2 to 7 .

2 is a view for explaining a MEMS mirror scan control signal and its problems.

The scan control signal sent to the MEMS mirror 1420 forms a sawtooth waveform as shown in FIG. 2 . The voltage can be 10~10V, and the voltage magnitude and width of the sawtooth wave are adjustable. In addition, it is preferable that the MEMS mirror is capable of both x-axis scan and y-axis scan.

For example, in the scan control signal of FIG. 2 , the signal of the rising part 10 is a signal that drives the MEMS mirror so that the light reflected from the MEMS mirror scans in the x-axis, and the signal of the falling part 20 is the MEMS mirror It is a signal that drives to return to the original position after stopping.

As described above, in SOC (System On Chip), which is a conventional 32-bit microcontroller, by using a timer interrupt method to control the MEMS mirror and cutting off the signal at a specific time (30), such a sawtooth wave was implemented to control the scan. .

However, when the scan is controlled using the sawtooth wave implemented in such a way, the MEMS mirror vibrates non-linearly in the sections 30 and 31 where the signal is sharply bent. When image processing on the scanned tomography was performed, there was a problem that was the biggest cause of serious errors such as repeating the same image several times.

In order to solve this problem, in the present invention, a scan signal is implemented by obtaining a Fourier series of a periodic function, but by obtaining a Fourier series for an optimal n value in which the mirror shake phenomenon disappears and using it as a scan signal, the mirror To generate the best image without shaking and without sagging, this will be described with reference to FIGS. 3 and 4 .

3 is a diagram illustrating a general sawtooth wave signal.

When the period of the function in Fig. 3 is T, it is assumed that from -T to 0 and from T to 0, it has the following function form

[Equation 1]

[Equation 2]

The Fourier series can be obtained by directly applying the formula for obtaining the Fourier coefficient.

in other words,

[Equation 3]

[Equation 4]

[Equation 5]

[Equation 6]

In Equation 4 and 5, if Fourier coefficients a(n) and b(n) are input to the program as functions for n, and these are summed as in Equation 6, the desired Fourier series can be calculated by computer operation. can be saved

Equation 6 shows the case of summing up to n=5, and how much of this n is summed is a very important part. That is, while changing n, the most appropriate value of n should be determined by grasping the waveform and the operating state of the MEMS mirror.

4 is a diagram in which a sawtooth signal is implemented as a Fourier series in the case of n=5 and n=10.

4 is a result for the case where T=2, A=1, B=0.2 in the function, and is a Fourier series graph obtained when the red dotted line in FIG. 4(a) is n=5, FIG. 4(b) ) is a Fourier series graph obtained when the red dotted line is n = 10. In each graph, a solid black line indicates a sawtooth wave as shown in FIG. 3 .

In fact, in the results derived from Equation 6 above, when 1≤n≤4, the sawtooth waveform itself is not formed and the MEMS mirror does not operate, and when 6≤n≤10, the result is very close to the sawtooth waveform. Mirror jitter continues intermittently.

From this, in Equation 6, it was confirmed that the shaking phenomenon of the MEMS mirror disappears and the scan operation is smooth in the scan control signal by the Fourier series in the case of n=5, and the image obtained thereby is also in a clear state without sagging.

5 is a diagram illustrating a trigger signal of a line scan camera.

5( a ) shows a trigger signal 60 and a rectangular waveform 70 of a line scan camera. The trigger signal 60 is a signal outputting an image formed on the focal plane 10 (eg, a line scan sensor, see FIG. 1 ) of the line scan camera, and the image formed on the line scan sensor 10 at once is described above. As described above, when the MEMS mirror 1420 is at a point during the x-axis scan, light is transmitted to a specific depth of the object 40, so that the image of one line from the surface of the object 40 to the corresponding depth becomes this This one-line image is acquired by the control and image acquisition device 1800, and continuously, according to the x-axis scan of the MEMS mirror 1420, one-line images up to a specific depth at each point on the x-axis are continuously controlled and imaged. Acquired by the acquisition device 1800, as a result, the control and image acquisition device 1800 sums up one line of images up to the corresponding depth of the target object 40 to a specific depth to a specific depth with respect to the x-axis line of the target object A tomography image of one side of the surface is acquired, and further, when tomography images of adjacent surfaces are continuously acquired as the MEMS mirror 1420 performs a y-axis scan, a 3D tomography image up to a specific depth of the object 40 is acquired. it could be done

At this time, the width 71 of the rectangular waveform 70 is also changeable by setting, left and right movement is possible, and it is also adjustable by setting the time 61 between the trigger signals 60 .

The multiplication of the rectangular waveform 70 and the trigger signal 60 finally forms a trigger signal of the line scan camera. This final trigger signal is shown in FIG. 5( b ).

6 is a flowchart illustrating a sequence for controlling the MEMS mirror control apparatus 1600 according to the present invention.

6 shows a sequence in which the control and image acquisition device 1800 of FIG. 1 or 7 controls the MEMS mirror control device 1600 . The control and image acquisition apparatus 1800 may be, for example, a PC, and may perform control as shown in FIG. 6 by a computer program operating in the PC.

Referring to FIG. 6 , first, the control and image acquisition apparatus 1800 may receive control parameters for the MEMS mirror 1420 ( S601 ). The control parameter may be, for example, the voltage of the scan control signal, which is a sawtooth wave, or the width of the sawtooth wave. That is, it is preferable to adjust the voltage of the scan control signal, which is a sawtooth wave, or the width of the sawtooth wave. In addition, the value of n in the case of forming the sawtooth scan control signal as a Fourier series, which has been described with reference to FIGS. 3 and 4 , may also be configured to be changeable. Of course, as described above, it is preferable to use the optimal n value in actual driving through testing of several n values, and in the example of FIG. 4 , it has been described that the case where n=5 has an optimal result. The control and image acquisition device 1800 transmits the input MEMS mirror control parameter to the MEMS mirror control device 1600 ( S602 ).

In addition, a line scan camera trigger signal control parameter as described with reference to FIG. 5 may also be input ( S603 ). The control parameter in this case may be the width 71 of the rectangular waveform 70 , the left-right movement or the distance 61 between the trigger signals 60 , as described with reference to FIG. 5 . The control and image acquisition device 1800 also transmits the line scan camera trigger signal control parameter input as described above to the MEMS mirror control device 1600 (S604).

Thereafter, the control and image acquisition apparatus 1800 transmits a 2D scan command to the MEMS mirror control apparatus 1600 according to the user's 2D scan input ( S605 ) or the like ( S606 ). In this case, the MEMS mirror performs a scan on the x-axis and repeatedly scans the same line on the x-axis. Thereafter, the 3D scan command is transmitted to the MEMS mirror control device 1600 according to the user's 3D scan input (S607) (S608). In this case, the MEMS mirror performs not only a scan on the x-axis but also a scan on the y-axis, and as a result, a 3D cross-section of the object 40 up to a certain depth can be viewed.

Similarly to the x-axis scan, the y-axis scan may be performed by a scan control signal formed by a Fourier series operation in the same manner as in FIGS. 3 and 4 .

Thereafter, when a user's scan stop is input (S609), the control and image acquisition device 1800 transmits a scan stop command to the MEMS mirror control device 1600 (S610).

In the above, it is not limited to performing 3D scan according to 3D scan command after 2D scan according to 2D scan command, only 2D scan according to 2D scan command, or 3D scan according to 3D scan command from the beginning It is also possible to

7 is a diagram showing the configuration of the MEMS mirror control apparatus 1600 according to the present invention.

The MEMS mirror control device 1600 of FIG. 7 receives the control parameters from the control and image acquisition device 1800 to set the control parameters, and also performs 2D scan or Perform a 3D scan.

Referring to FIG. 7 , the communication interface conversion unit 160 converts a communication interface enabling communication between the control and image acquisition apparatus 1800 and the control signal generation unit 1620 . For example, when the control and image acquisition device 1800 is a PC and the control signal generator 1620 is configured with a CPU or DSP chip, a role of converting USB communication with the PC into serial communication with the CPU or DSP chip, etc. carry out

The control signal generator 1620 may use a general CPU, but more preferably a DSP chip capable of performing many operations more quickly. That is, in particular, a MEMS mirror scan control signal can be generated through a fast operation through a program driven in the DSP chip. In order to form the MEMS mirror scan control signal by the operation of the Fourier series as described above with reference to FIGS. 3 and 4 , such a fast operation is essential. In addition, the control signal generator 1620 is also responsible for forming the line scan camera trigger signal as described with reference to FIG. 5 . Such a trigger signal is a 3V level square wave signal, and is transmitted to the line scan camera 300 to acquire an image of the focal plane 10 , which is, for example, a kind of line scan sensor of FIG. 1 .

The MEMS mirror scan signal formed by the control signal generator 1620 is a digital signal, and the D/A converter 1630 converts it into an analog signal to control the x-axis scan control signals (X+, X-) and the y-axis scan. Signals (Y+, Y-) are output, and the low voltage analog scan control signal is amplified into a high voltage analog scan control signal in the high voltage amplifier 1640. This high voltage analog scan control signal is output from 0V up to 150V. This is possible, and the MEMS mirror 1420 is controlled by this signal. The high voltage amplifier 1640 may include an OP-AMP.

The high voltage converter 1650 is, for example, a DC/DC converter that converts 5V power supplied from the control and image acquisition device 1800 such as a PC into a high voltage (150V) and provides it to the high voltage amplifier 1640 .

8 is a flowchart illustrating a control sequence of the control signal generator 1620 in the MEMS mirror control apparatus 1600 of FIG. 7 .

As described above, the control signal generating unit 1620 may use a general CPU, but more preferably, a function such as forming a MEMS mirror scan control signal by operation of a Fourier series can be performed more quickly. It is preferable to use a DSP chip.

First, the control signal generator 1620 receives a control parameter for the MEMS mirror 1420 from the control and image acquisition device 1800 (S701), and sets it as a control parameter for the MEMS mirror 1420 (S702) . These control parameters have been described above with reference to FIG. 6 . Afterwards, a MEMS mirror scan control signal is formed according to these control parameters.

Also, the control signal generator 1620 receives the line scan camera trigger signal control parameter as described with reference to FIG. 5 from the control and image acquisition device 1800 (S703), and sets it as a control parameter for the camera trigger signal do (S704). These control parameters have also been described above with reference to FIG. 6 . A subsequent line scan camera trigger signal is formed according to these control parameters.

Thereafter, when the control signal generator 1620 receives the 2D scan command from the control and image acquisition device 1800 ( S705 ), the x-axis MEMS is performed by the Fourier series calculation method as described with reference to FIGS. 3 and 4 . A mirror scan control signal is formed and output (S706). This output signal is input to the D/A converter 1630 as described above with reference to FIG. 7 and is converted into an analog signal.

In addition, the control signal generator 1620, upon receiving the 2D scan command from the control and image acquisition device 1800 (S705), generates and outputs a line scan camera trigger signal (S707), as described above with reference to FIG. 7 . As shown, this trigger signal is directly input to the line scan camera 300 .

When the control signal generator 1620 receives the 2D scan command from the control and image acquisition device 1800 ( S708 ), the y-axis MEMS mirror scan is performed by the Fourier series calculation method as described with reference to FIGS. 3 and 4 . A control signal is formed and output (S709). This output signal is also input to the D/A converter 1630 as described above with reference to FIG. 7 and is converted into an analog signal.

Thereafter, when a scan stop command is received from the control and image acquisition device 1800 (S710), the control signal generator 1620 stops outputting the MEMS mirror control signal (S711), and also the line scan camera trigger signal output Stop (S712).

As described above with reference to FIG. 6, in the above description, after 2D scan according to the 2D scan command, the 3D scan according to the 3D scan command is not limited, and only the 2D scan according to the 2D scan command is performed, Alternatively, it is also possible to perform a 3D scan according to a 3D scan command from the beginning.

10, 20: focal plane
30: lens central axis
40: object
50: second light source
60: trigger signal
70: rectangular waveform
100: lens arrangement
200: lens arrangement
1000: optical coherence tomography imaging system
1100: light source unit
1110: first light source
1120: isolator (isolator)
1200: coupler (coupler)
1300: reference (reference) unit
1310: collimator
1320: focusing lens
1330: reference mirror (mirror)
1400: scan unit
1410: collimator
1420: MEMS mirror
1430: beam splitter (beam splitter)
1440: focusing lens
1500: optical coherence tomography image capture unit
1510: third light source
1520: collimator
1530: grating part
1600: MEMS mirror control unit
1700: surface image capture unit
1800: control and image acquisition device
1810: display device

Claims (19)

A MEMS mirror control device comprising:
a communication interface conversion unit for performing communication interface conversion between the control and image acquisition apparatus and the control signal generation unit;
a control signal generator for generating a MEMS mirror scan control signal; and,
A D/A converter that converts the MEMS mirror scan control signal formed by the control signal generator into a low-voltage analog scan control signal
including,
The control signal generator,
A MEMS mirror scan control signal is formed by the operation of the Fourier series,
The Fourier series calculation of the control signal generator is performed so that, when the MEMS mirror is scanned, shaking at both ends of the scan is removed,

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sign,
MEMS mirror control unit. The method according to claim 1,
A high voltage amplifier amplifying the low voltage analog scan control signal output from the D/A converter into a high voltage analog scan control signal.
MEMS mirror control device further comprising a. 3. The method according to claim 2,
A high voltage converter that converts the low voltage power supplied from the control and image acquisition device into a high voltage and provides it to the high voltage amplifier
MEMS mirror control device further comprising a. delete delete The method according to claim 1,
The control signal generator,
Ability to form a line scan camera trigger signal and forward it to the line scan camera
MEMS mirror control device further comprising a. A method for the control signal generating unit of claim 1 to perform MEMS mirror control, comprising:
(a) receiving the MEMS mirror control parameters from the control and image acquisition device;
(b) setting the parameter as a control parameter for forming a MEMS mirror scan control signal;
(c) receiving a scan command of the MEMS mirror from the control and image acquisition device; and,
(d) forming a MEMS mirror scan control signal according to the scan command
including,
The MEMS mirror scan control signal of step (d) is,
It is formed by the operation of Fourier series,
The Fourier series calculation is such that, when scanning the MEMS mirror, vibrations at both ends of the scan are removed,

saved by
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ego,

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sign,
Method of performing MEMS mirror control by the control signal generator. 8. The method of claim 7,
The scan command of step (c) is,
Anything that is a 2D scan command or a 3D scan command
Method of performing MEMS mirror control of the control signal generator, characterized in that. 9. The method of claim 8,
When the scan command in step (c) is a 2D scan command,
The MEMS mirror scan control signal of step (d) is,
What is the x-axis scan control signal
Method of performing MEMS mirror control of the control signal generator, characterized in that. 10. The method of claim 9,
After step (d),
(e) receiving a 3D scan command of the MEMS mirror from the control and image acquisition device; and,
(f) forming a y-axis scan control signal of the MEMS mirror according to the scan command
Method for performing MEMS mirror control of the control signal generator further comprising a. delete delete 8. The method of claim 7,
Prior to step (c),
(c01) receiving a line scan camera trigger signal control parameter from the control and image acquisition device; and,
(c02) setting the parameter as a control parameter for forming a line scan camera trigger signal;
further comprising,
When the scan command of the MEMS mirror is received in step (c),
(g) forming a line scan camera trigger signal and passing it to the line scan camera;
Method for performing MEMS mirror control of the control signal generator further comprising a. A computer program stored in a non-transitory storage medium for the control signal generator of claim 1 to perform MEMS mirror control, comprising:
It is stored in a non-transitory storage medium, and by the processor,
(a) receiving the MEMS mirror control parameters from the control and image acquisition device;
(b) setting the parameter as a control parameter for forming a MEMS mirror scan control signal;
(c) receiving a scan command of the MEMS mirror from the control and image acquisition device; and,
(d) forming a MEMS mirror scan control signal according to the scan command
contains a command that causes it to be executed,
The MEMS mirror scan control signal of step (d) is,
It is formed by the operation of Fourier series,
The Fourier series calculation is such that, when scanning the MEMS mirror, vibrations at both ends of the scan are removed,

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A computer program stored in a non-transitory storage medium for the control signal generating unit to control the MEMS mirror.
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