JP2011247601A - Minute flow field imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To overcome difficulty in acquiring image data due to reasons such as processing error or manufacturing error in a device or in a part and influence of refraction index unique to fluid and acquire an effective image for analysis of fluid velocity in a micro scale minute flow field and the like by a single imaging apparatus.SOLUTION: A minute flow field imaging apparatus includes an imaging apparatus (11) for imaging a particle image of visual fluid in the minute flow field (M) and a microscope (12) which is optically connected to the imaging apparatus. A plurality of first reflection surfaces (17,17a) and a plurality of second reflection surfaces (16,16a) respectively facing the first reflection surfaces and also arranged in an optical path of the microscope are arranged in between the microscope and the minute flow field. The minute flow field imaging apparatus includes an angle adjustment mechanism for adjusting the angles of the first or the second reflection surfaces and a position adjustment mechanism for adjusting the positions of the first or the second reflection surfaces. Reflectance of the particle in the minute flow field is reflected by the first and the second reflection surfaces and makes incidence on the optical path of the microscope and a plurality of images for the same particle obtained from different viewpoints are imaged on a single imaging surface of the imaging apparatus.

Description

  The present invention relates to a microfluidic field imaging device, and more particularly to a microfluidic field imaging device for visualizing a fluid and measuring a fluid velocity or the like of the microfluidic field.

  A visualization measurement technique is known in which tracer particles for visualizing a fluid are mixed as a marker into a fluid flow and the fluid velocity of a flow field is measured. In the direct imaging method known as visualization measurement technology, tracer particles are continuously photographed at short time intervals by methods such as double-exposure photography or high-speed camera photography or frame-crossing photography using a pulse laser and a digital CCD camera. Thus, the moving distance of the particles is measured. The velocity of the particles is calculated by dividing the distance traveled by the time interval.

  PIV (Particle Image Velocimetry) technology is a measurement technique that is widely used as a direct imaging method for examining the flow velocity distribution. According to the PIV measurement technique, two in-plane velocity components in the sheet light can be measured.

  However, the flow aspect in an actual flow field is complex, and many flows have a velocity three component in three-dimensional space. For this reason, in actual speed measurement, it is often necessary to obtain three-dimensional speed information. However, in order to perform three-dimensional measurement, it is essential to obtain the correspondence between physical space and image coordinates.

In order to obtain the correspondence between the physical space and the image coordinates, it is necessary to use at least two cameras and take images of the flow field from different viewpoints.
For example, the stereo PIV technology uses two cameras arranged in stereo as described in Japanese Patent Application Laid-Open No. 2004-286733 (Patent Document 1), and measures three components in the laser sheet light with two cameras. This is a measurement technique for measuring the two-dimensional three components of the fluid velocity.

  On the other hand, a holographic PIV technique is known as a technique for measuring a three-dimensional three component of fluid velocity (Japanese Patent Laid-Open No. 2007-298327 (Patent Document 2) and Japanese Patent Laid-Open No. 2005-315850 (Patent Document 3)). ). While the stereo PIV technology is a two-dimensional measurement technology, the holographic PIV technology has an advantage in that it is a three-dimensional measurement technology.

  In the holographic PIV technique described in Patent Document 2, the optical axes of the two cameras are arranged at positions that are spaced apart from the particles to be measured. Particle interference images are captured by two cameras. However, in order to acquire an interference image, it is necessary to adjust the optical path using various lenses, and the apparatus configuration or system configuration becomes complicated.

  On the other hand, according to the holographic PIV technique described in Patent Document 3, the three-dimensional position information of the measurement target can be acquired by one camera by using two colors of laser light. However, as with the holographic PIV technology of Patent Document 2, the holographic PIV technology of Patent Document 3 also requires adjustment of the optical path using various lenses in order to obtain an interference image. The system configuration is complicated. In addition, the laser device that emits laser light of two colors is very expensive, and the cost for constructing the measurement system increases.

  Furthermore, in such holographic PIV technology, it takes a very long time to acquire the hologram image and process the image data, and the image acquired by the holographic method is a spectral image. Thus, there is a problem in that the amount of movement or the like cannot be intuitively grasped from the image obtained by the above, and therefore the quality of the measurement result cannot be judged until all the analysis processes are completed. In addition, it is known that hologram images have a weakness that they are vulnerable to noise, but it is difficult to shoot images without noise. For this reason, there is a concern that the reliability of measurement results may be impaired by the effects of noise. The

  As another three-dimensional measurement technique, two cameras are arranged in stereo, or three or more cameras are arranged in stereo, and a three-dimensional PTV that measures three velocity components of individual tracer particles in a three-dimensional space ( Particle Tracking Velocimetry) technology is known.

  However, in any three-dimensional measurement system, it is necessary to arrange a plurality of imaging devices (cameras) in stereo, and to connect a power supply line and a control signal line to the illumination device and each imaging device. Not only does the apparatus configuration become complicated, but the overall configuration of the system tends to increase in size in order to secure installation space and wiring space for the photographing apparatus. However, when measuring a micro-scale microfluidic field, there is a circumstance where it is difficult to ensure a sufficient device installation space and wiring space, a sufficient peripheral device placement space, and the like because the measurement target is very small.

  In addition, the holographic PIV (Patent Documents 2 and 3) has problems such as an expensive system, complicated apparatus, delay in data acquisition and data processing, delay in recognition of measurement results, and influence of noise as described above. To do.

  For this reason, the present inventors have continuously researched and developed a microfluidic field imaging device that measures the fluid velocity of the microfluidic field with a single imaging device (camera), mirror, and prism. With regard to a microfluidic field imaging device having such a configuration, a technique for acquiring a particle image from a plurality of viewpoints by using a single imaging device using two mirrors and a prism is the academic paper “Development of Stereo” by the present inventors. Micro PTV and Its Application to a Rotating Disk Flow (8th International Symposium On Particle Image Velocimetry-PIV09) "(Non-Patent Document 1).

JP 2004-286733 A JP2007-298327A JP 2005-315850 A Academic Paper “Development of Stereo Micro PTV and Its Application to a Rotating Disk Flow (8th International Symposium On Particle Image Velocimetry-PIV09)” (H. J. Lee, S. Mitorida and K. Nishino, August 2009)

  Although the technique described in Non-Patent Document 1 has achieved the intended research purpose of acquiring particle image data for measuring the fluid velocity of a microfluidic field by a single imaging device (camera), Increasing the magnification of the microscope by setting the measurement area to a very small dimension of about 500 μm on a side increases the effects of processing errors or manufacturing errors on the device or parts, and provides effective image data for speed analysis etc. There was a problem that it was difficult to obtain.

  It is considered that such a problem can be avoided theoretically by improving processing accuracy and manufacturing accuracy. However, in reality, it has been found that no matter how much the processing accuracy and the manufacturing accuracy can be improved, such a problem cannot be solved. This is considered to be due to the fact that the measurement area is an extremely small area.

  Further, it has been further found that when a micro-scale microfluidic field is measured, the same problem can occur due to the influence of the refractive index inherent to the fluid.

  The present invention has been made in view of such a problem, and an object of the present invention is to provide a processing error of a device or a component in a microfluidic field imaging device for measuring a fluid velocity of a microfluidic field or the like. A single imaging device that eliminates the difficulty of acquiring image data due to manufacturing errors and the influence of the refractive index inherent to the fluid, and analyzes the fluid velocity of a micro-scale microfluidic field. It is an object to provide a microfluidic field imaging device that can be acquired by:

In order to achieve the above object, the present invention provides an imaging device for capturing a particle image of a visualization fluid in a microfluidic field, a microscope optically coupled to the imaging device, and the microscope and the microfluidic field. In a microfluidic field imaging device that includes a first reflecting surface and a second reflecting surface disposed between, and acquires image data for measuring a flow velocity of the visualization fluid by the imaging device,
The angles of the plurality of first reflection surfaces, the plurality of second reflection surfaces facing each of the first reflection surfaces and arranged in the optical path of the microscope, and the first or second reflection surface are adjusted. An angle adjustment mechanism, and a position adjustment mechanism for adjusting the position of the first or second reflecting surface;
The angle and position of the reflecting surface are adjusted by the angle adjusting mechanism and the position adjusting mechanism, and the reflected light of the same particle in the microfluidic field is reflected by the first and second reflecting surfaces to enter the optical path in the microscope. Provided is a microfluidic field imaging device characterized in that a plurality of images of the same particle obtained from different viewpoints are formed on a single imaging surface of the imaging device.

  According to the present invention, the microfluidic field imaging device includes an angle adjustment mechanism that adjusts the angle of the first or second reflection surface, and a position adjustment mechanism that adjusts the position of the first or second reflection surface. The optical path of the reflected light of the particles can be corrected so that a plurality of particle images of the same particle obtained from different viewpoints are formed on the imaging surface of the imaging device. According to the microfluidic field imaging device provided with such an optical path correction means, even when the magnification of the microscope is increased and the measurement area is miniaturized, a plurality of particle images of the same particle are captured as a single image. It can be reliably acquired by the device.

  According to the microfluidic field imaging device of the present invention, it is possible to eliminate the difficulty in acquiring image data due to the processing error or manufacturing error of the device or parts, the influence of the refractive index inherent to the fluid, and the like. It is possible to acquire effective image data for analyzing the three-dimensional three-component of the fluid velocity in the single imaging device and measure the fluid velocity of the microfluidic field. Further, by applying the present invention to a microfluidic field imaging device for a three-dimensional PTV measurement system, not only the three-dimensional three components of the fluid velocity in the microfluidic field but also the particle position and particle size measurement, ie, micro Image data effective for measuring the shape of an object, measuring the displacement of a micro object, and measuring the deformation of a micro object can be acquired by a single imaging device.

FIG. 1 is a system configuration diagram schematically showing a configuration of a three-dimensional measurement system including a microfluidic field imaging device according to the present invention. FIG. 2 is a schematic longitudinal sectional view conceptually showing the structure of the microfluidic field imaging device. FIG. 3 is a schematic longitudinal sectional view conceptually showing the configuration of the microfluidic field imaging device, and shows a cross section orthogonal to FIG. FIG. 4 is a plan view showing the structure of a stereo optical attachment provided with a prism position adjusting mechanism and a mirror angle adjusting mechanism. FIG. 5 is a front view of the stereo optical attachment shown in FIG. FIG. 6 is a right side view of the stereo optical attachment shown in FIG. 7 is a left side view of the stereo optical attachment shown in FIG. 8 is a cross-sectional view taken along the line II of FIG. 9 is a cross-sectional view taken along the line II-II in FIG. 10 is a cross-sectional view taken along line III-III in FIG. FIG. 11 is a longitudinal sectional view showing a tightening structure of the mirror position adjusting screw. FIG. 12 is a longitudinal sectional view showing the adjustment direction of the prism and mirror. FIG. 13 is a cross-sectional view showing the adjustment direction of the prism and mirror. FIG. 14 is a schematic longitudinal sectional view conceptually showing a modification of the microfluidic field imaging device.

  According to a preferred embodiment of the present invention, the angle adjusting mechanism adjusts the angle of the first reflecting surface, and the position adjusting mechanism adjusts the position of the second reflecting surface.

  Preferably, a second position adjusting mechanism for adjusting the position of the first reflecting surface is further provided. More preferably, the angle adjusting mechanism adjusts the angle of the first reflecting surface about an axis perpendicular to the optical axis of the microscope, and the position adjusting mechanism is configured to adjust the second reflecting surface in a direction parallel to the optical axis of the microscope. And the position of the second reflecting surface in a plane perpendicular to the optical axis of the microscope is adjusted.

  According to a further preferred embodiment of the present invention, the first reflecting surface is composed of a reflecting surface of a mirror supported so as to be adjustable in angle by an angle adjusting mechanism, and the second reflecting surface is adjusted in position by a position adjusting mechanism. It consists of a reflective surface of a prism or mirror that is supported and arranged in the optical path of the microscope.

  Preferably, a plurality of second reflecting surfaces are formed by a prism disposed on the optical axis of the microscope, and the first reflecting surface is formed by a plurality of mirrors spaced from the prism in a direction perpendicular to the optical axis of the microscope. It is formed. The optical path of the reflected light reflected from the particles is formed between the prism and the mirror.

  If desired, a third reflecting surface that reflects the illumination light of the light source toward the microfluidic field is attached to the support of the second reflecting surface. As a modification, illumination light for a microfluidic field may be applied to the microfluidic field by coaxial epi-illumination of a microscope.

  In a preferred embodiment of the present invention, the angle adjusting mechanism and / or the position adjusting mechanism includes an elastic body that elastically holds the support of the reflecting surface, a support surface that supports the support so as to be relatively displaceable, and a support. And an adjusting tool for relative displacement with respect to the bearing surface. The elastic body elastically urges the support body against the bearing surface, and the support body makes surface contact with the bearing surface. The adjustment tool presses the support to displace the support, and the bearing surface regulates the direction of displacement of the support.

  Preferably, an optical attachment including the reflection surface, a support for the reflection surface, and a base for supporting the support is disposed between the microscope and the microfluidic field. The position of the base is fixed with respect to the imaging device and the microscope.

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

  FIG. 1 is a system configuration diagram schematically showing a configuration of a three-dimensional measurement system including a microfluidic field imaging device according to the present invention. 2 and 3 are schematic cross-sectional views conceptually showing the structure of the microfluidic field imaging device.

  The three-dimensional measurement system shown in FIG. 1 includes a microfluidic field imaging device 1, a PC (personal computer) 2, a delay generator 3, a function generator 4, a laser device 5, and a fiber scope 6. The microfluidic field imaging device 1 includes an imaging device 11, a microscope 12, and a stereo optical attachment 10.

  The imaging device 11 is connected to the PC 2 by a control signal line (indicated by a two-dot chain line). The PC 2 is connected to the delay generator 3 by a control signal line. The delay generator 3 is connected to the function generator 4, the laser device 5, and the microscope 12 by a control signal line. A fiberscope 6 is connected to the laser device 5, and the emission unit 7 of the fiberscope 6 supplies illumination light for photographing to the fluid in the measurement region M. The measurement region M is a microscale flow field, and is a regular cubic region having a side of 1 mm or less, for example, about 500 μm.

  The measurement area M is located immediately below the stereo optical attachment 10. The fluid to be measured flows through the measurement region M. Reflected light (indicated by arrows) of the tracer particles P (FIGS. 2 and 3) contained in the fluid is incident on the objective lens 13 of the microscope 12 via the stereo optical attachment 10. As the objective lens 13 of the microscope 12, for example, an objective lens “M PIAN APO SL 20 ×, NA 0.28” manufactured by Mitutoyo can be suitably used.

  The optical axis of the microscope 12 is set in the vertical direction, and the upper end of the microscope 12 is connected to the imaging device 11. The imaging device 11 is composed of a digital CCD camera capable of acquiring image data. The particle image magnified by the microscope 12 is imaged on an imaging surface (not shown) of the imaging device 11.

  The movement of the fluid is visualized as the movement of the tracer particle P and is photographed by the imaging device 11. The PC 2 stores the image of the imaging device 11 and calculates the moving speed of the tracer particles P, that is, the flow velocity of the fluid using a particle image processing algorithm.

For example, the following high-resolution digital CCD camera can be suitably used as the imaging device 11.
・ Product name: JAI "jAi CV-M2CL"
・ Number of effective pixels: 1600 (h) x 1200 (v)
・ CCD element size: 11.8mm (h) x 8.9mm (v)
・ Number of bits: 10bit
・ Shooting speed: 30fps / dual channel

As the laser device 5, a double pulse Nd: YAG laser (neodymium / yag laser) or the like is used. For example, the following Nd: YAG laser can be suitably used as the laser device 5.
-Product name: Surelite Q-switched Nd: YAG Laser manufactured by Continuum
・ Maximum emission frequency: 15Hz
・ Output: 170mJ / pulse @ 532nm
・ Pulse width: 4 to 6 ns

  If desired, the microscope 12 includes a laser light filter 14 that cuts the laser light and passes the fluorescent light. For example, a rugate / notch filter can be suitably used as the laser light filter. The Rugate notch filter cuts light of 519 nm to 545 nm and has a fluorescence transmission rate of 95% or more.

  The laser device 5 that has received the trigger signal of the delay generator 3 supplies a double pulse laser to the fiberscope 6 as illumination light. The illumination light is guided to the optical fiber of the fiberscope 6 and irradiated from the emitting unit 7 to the fluid in the measurement region M.

  The PC 2 reads and stores the image data of the image taken by the imaging device 11 and saves the image data, and adjusts the length of the minute time interval of the delay generator 3. The delay generator 3 controls the pulse interval of the laser device 5. As the delay generator 3, "VSD1000" manufactured by Flotech Research, and the number of output channels: 7ch can be suitably used.

  The function generator 4 controls the output frequency of the laser device 5 to an arbitrary frequency. As the function generator 4, for example, FG3021B manufactured by Tektronix can be suitably used.

  2 and 3 schematically show the configuration of the stereo optical attachment 10.

  The stereo optical attachment 10 is attached to a prism 16 positioned immediately below the objective lens 13, a pair of mirrors 17 disposed on both sides of the prism 16, a support member 18 that supports the prism 16, and a lower surface of the support member 18. And a prism 19.

  The optical path of the illumination light is indicated by an arrow in FIG. The emission unit 7 of the fiberscope 6 emits illumination light in the horizontal direction. The reflecting surface 19 a of the prism 19 reflects the illumination light vertically downward and changes the traveling direction of the light toward the measurement region M. The tracer particles P mixed in the fluid reflect the illumination light incident on the measurement region M as scattered light.

  The optical path of the reflected light between the tracer particle P and the objective lens 17 is indicated by an arrow in FIG. Although the reflected light of the tracer particles P is scattered light, only the optical path of the reflected light incident on the objective lens 13 is indicated by arrows in FIG.

  The reflecting surfaces 17a of the left and right mirrors 17 reflect the reflected light of the tracer particles P in the horizontal direction toward the reflecting surface of the prism 16, and change the traveling direction of the light. The left and right reflecting surfaces 16 a of the prism 16 reflect the reflected light reflected by the left and right mirrors 17 vertically upward, and change the traveling direction of the light toward the objective lens 13. The reflected light reflected by the left and right reflecting surfaces 16a of the prism 16 enters the objective lens 13 substantially in parallel, is magnified by the microscope 12, and forms an image on an imaging surface (not shown) of the imaging device 11.

  That is, since the pair of left and right optical paths are formed by the pair of left and right reflecting surfaces 17a and 16a, the reflected light (scattered light) of the tracer particle P is incident on the microscope 12 as reflected light of the tracer particle P obtained from different viewpoints. To do. As a result, two images of the single tracer particle P imaged from different viewpoints are formed on the imaging surface of the imaging device 11. Thus, according to the microfluidic field imaging device 1 configured as described above, one image data including two images of the single tracer particle P captured from different viewpoints can be acquired by the single imaging device 11.

  4, 5, 6, and 7 are a plan view, a front view, a right side view, and a left side view showing the structure of the stereo optical attachment 10. 8 and 9 are cross-sectional views taken along the line II of FIG. 4 and the line II-II of FIG. 8, and FIG. 10 is a cross-sectional view taken along the line III-III of FIG.

  The stereo optical attachment 10 includes a base 20, a prism holding mechanism 30, and a mirror holding mechanism 50. The prism holding mechanism 30 constitutes a position adjusting mechanism that supports the prism 16 so that the position of the prism 16 can be adjusted. The mirror holding mechanisms 50 are arranged in pairs on both sides of the prism 16 and support the respective mirrors 17 so that the angles can be adjusted, thereby constituting an angle adjusting mechanism.

  The base 20 is horizontally disposed at a predetermined position of the microfluidic field imaging device 1. The position of the base 20 is fixed by a frame (not shown) of the microfluidic field imaging device 1 or the like. 4 to 10, the width direction, the depth direction, and the height direction of the base 20 are shown as an X direction, a Y direction, and a Z direction.

  The prism holding mechanism 30 includes a support 31 fixed to the upper surface of the base 20 by a fixing screw 21 and a carrier 32 supported by the support 31 so as to be vertically displaced. As shown in FIG. 8, the column 31 has a guide groove 34 that guides the guide portion 33 of the carrier 32 in the vertical direction (vertical direction). A vertical adjusting screw 35 passes through the top wall portion 36 of the column 31 and contacts the upper end surface of the guide portion 33. A spring holder 37 is formed at the lower portion of the column 31, and a compression coil spring 38 is interposed between the lower end surface of the guide portion 33 and the spring holder 37. The tightening force of the adjusting screw 35 presses the guide portion 33 downward against the elastic repulsive force of the spring 38. The guide portion 33, the guide groove 34, the adjustment screw 35, and the spring 38 constitute a vertical position adjustment mechanism of the prism 16, and the prism 16 is entirely moved by tightening the adjustment screw 33 and displacing the guide portion 33 downward. The prism 16 can be displaced vertically upward (upward in the Z direction) by loosening the adjusting screw 33 and displacing the holder 37 upward. .

  The carrier 32 supports the support member 18 via the horizontal position adjustment mechanism 40. The horizontal position adjustment mechanism 40 includes a horizontal shaft portion 41 having a circular cross section, a Belleville spring 42 in a compressed state, an enlarged base portion 43 integrated with a base end portion of the horizontal shaft portion 41, and a connecting portion of the support member 18. And an arcuate bearing surface 44 formed on the surface. The horizontal shaft portion 41 passes through the horizontal through hole 45 of the carrier 32. A screw part 46 formed at the tip of the horizontal shaft part 41 is screwed into the screw hole 18 a of the support member 18. The horizontal shaft portion 41 and the support member 18 are integrally connected by fastening the screw portion 46 and the screw hole 18a. The support member 18 is formed with an arcuate bearing surface 47 that comes into surface contact with the arcuate bearing surface 44. The bearing surfaces 44 and 47 have substantially the same vertical direction (Z direction) curvature center axis, and the support member 18 can be horizontally displaced around the curvature center axis.

  As shown in FIG. 9, horizontal screw holes 48 are formed symmetrically on both sides of the horizontal shaft portion 41. The screw hole 48 penetrates the wall of the carrier 32 in the X direction. The adjusting screw 49 is screwed into each screw hole 48, and the tip of the adjusting screw 49 comes into contact with the shaft portion 41. When the adjustment screw 49 on one side is tightened and the adjustment screw 49 on the other side is released to displace the shaft portion 41, the shaft portion 41 is displaced relative to the carrier 32 in the X direction. Since the bearing surfaces 44 and 47 maintain a sliding contact state by the elastic repulsive force of the spring 42, the support member 18 is horizontally displaced in accordance with the horizontal displacement of the shaft portion 41. The horizontal displacement of the support member 18 causes a horizontal displacement in the X direction of the prisms 16 and 19 disposed at the tip of the support member 18.

  As shown in FIG. 4, support arms 22 and 23 for supporting the casing 51 of the mirror holding mechanism 50 are disposed on the upper surface of the base 20. The casing 51 has a substantially rectangular parallelepiped shape having a long axis in the X direction. The mirror holding mechanism 50 is disposed symmetrically on both sides of the prism 16 and supports the mirror 17 so that the angle can be adjusted.

  The housing 51 of the mirror holding mechanism 50 located on the right side in FIG. 4 is fixed to the support arm 22 by the fixing screw 21. On the other hand, the housing 51 of the mirror holding mechanism 50 located on the left side in FIG. 4 is supported by a screw 25 that supports the support arm 23 and the housing 51 so as to be relatively displaceable in the X direction.

  FIG. 11 is a cross-sectional view showing the tightening structure of the screw 25.

  The screw hole 26 drilled in the support arm 23 has a horizontal cross section elongated in the X direction. A spring washer 27 is interposed between the screw head of the screw 25 and the upper surface of the housing 51. The housing 51 can be displaced relative to the support arm 23 in the X direction by a gap 28 formed between the outer surface of the screw 25 and the inner surface of the screw hole 26.

  FIG. 10 shows the configuration of the X-direction adjusting mechanism 70 that relatively displaces the support arm 23 and the casing 51 in the X direction. The X direction adjustment mechanism 70 constitutes a second position adjustment mechanism.

  The X-direction adjusting mechanism 70 includes a projecting portion 71 that is integrally formed on the upper surface of the housing 51 and a pair of left and right adjusting screws 73 that abut on the projecting portion 71. The protrusion 71 is disposed in a recess 74 formed on the lower surface of the support arm 23, and the adjustment screw 73 is screwed into a screw hole 72 extending in the X direction and abuts against the protrusion 71. The housing 51 is displaced in the X direction in accordance with the screwing positions of the left and right adjusting screws 73.

  FIG. 10 shows the structure of the left and right mirror holding mechanisms 50. As described above, the mirror holding mechanism 50 constitutes an angle adjustment mechanism.

  The mirror holding mechanism 50 includes a hemispherical holder 52 that supports the mirror 17 and a horizontal shaft portion 53 having a circular cross section that extends in the X direction. The mirror 17 is fixed in the recess of the holder 52. A through hole 54 extending in the X direction is formed in the central portion of the holder 52, and the horizontal shaft portion 53 is disposed horizontally in the through hole 54. The front end portion of the horizontal shaft portion 53 is integrally connected to the holder 52. An outer tube 55 having a substantially square cross section is fixed to the base end portion of the horizontal shaft portion 53. A compression coil spring 56 is inserted between the distal end surface 55 a of the outer tube 55 and the stepped portion 54 a in the through hole 54. The spring 56 urges the horizontal shaft portion 53 and the outer tube 55 outward in the X direction.

  The adjusting screw 57 is screwed into the screw hole 58 of the housing 51. The tip of the adjustment screw 57 contacts the outer surface of the outer tube 55. As shown in FIGS. 6 and 7, the adjusting screw 57 is disposed at an angular interval of 90 degrees, and restrains the outer tube 55 from the Y direction and the Z direction.

  Since the base end portion of the horizontal shaft portion 53 is displaced in the Y direction and the Z direction in accordance with the screwing position of each adjusting screw 57, the horizontal shaft portion 53 is in the Y direction or Z direction with respect to the central axis line in the X direction. Inclined in the direction.

  As shown in FIG. 10, a hemispherical recess 51a having a shape complementary to the hemispherical surface of the holder 52 is formed on the front end surface of the housing 51, and the hemispherical surface of the holder 52 has a hemispherical recess. It is in sliding contact with the inner surface of 51a. The holder 52 rotates within the hemispherical recess 51 a according to the inclination of the horizontal shaft portion 53, and changes the angle of the mirror 17.

  12 and 13 are a longitudinal sectional view and a transverse sectional view showing adjustment directions of the prism 16 and the mirror 17 by the prism holding mechanism 30, the horizontal position adjusting mechanism 40, the mirror holding mechanism 50, and the X direction adjusting mechanism 70, respectively.

  12 and 13 show the adjustment directions α, β, γ, and η of the prism 16 and the mirror 17 by the prism holding mechanism 30, the horizontal position adjusting mechanism 40, the mirror holding mechanism 50, and the X direction adjusting mechanism 70, respectively. . According to the microfluidic field imaging device 1 having such an adjustment mechanism, the optical path between the measurement region M and the imaging surface of the imaging device 11 can be finely corrected or finely adjusted. An image effective for analyzing the fluid velocity of a micro-scale microfluidic field is surely obtained by the single imaging device 11 by eliminating the influence of the processing image or the manufacturing error and the acquired image data due to the difference in the measurement target fluid. Can be acquired.

  FIG. 14 is a schematic cross-sectional view conceptually showing a modification of the microfluidic field imaging device 1.

  The microfluidic field imaging device 1 shown in FIG. 14 irradiates the measurement region M with the epi-illumination of the microscope 12 indicated by a broken line by the prism 16 and the mirror 17, and reflects the reflected light of the tracer particles P by the prism 16 and the mirror 17. It has the structure made to inject into. Other configurations are the same as those of the above-described embodiment.

  The preferred embodiments and examples of the present invention have been described in detail above. However, the present invention is not limited to the above-described embodiments and examples, and is within the scope of the present invention described in the claims. Various modifications or changes are possible.

  For example, in the above embodiment, the reflecting surface of the prism disposed at the center is used as the second reflecting surface, but the second reflecting surface may be formed by a plurality of mirrors having the same function as the prism.

  Further, in the above-described embodiment, each adjustment mechanism is a mechanism that is manually operated, but an adjustment mechanism having a configuration that is remotely operated or automatically controlled may be employed.

  Furthermore, in the above-described embodiments, the configuration including a pair of mirrors on both sides of the prism has been described, but a configuration including three or more mirrors may be employed. In this case, three or more reflecting surfaces that reflect the reflected light of the three or more mirrors toward the objective lens of the microscope are arranged at the position of the prism.

  The microfluidic field imaging device of the present invention is a microfluidic field for performing three-dimensional three-component measurement of the flow velocity of a visualization fluid flowing in a microscale microfluidic field set to a size of 1 mm or less, for example, about 500 μm. It is suitably used for an imaging system. Further, by applying the present invention to a microfluidic field imaging system for three-dimensional PTV measurement, not only the three-dimensional three components of the fluid velocity in the microfluidic field, but also particle position measurement, particle size measurement, etc. Effective image data can also be acquired by a single imaging device for effective image data for object shape measurement, micro object displacement measurement, and micro object deformation measurement. Therefore, according to the microfluidic field imaging device of the present invention, there is no need for a plurality of imaging devices, complicated control systems and control mechanisms, a large number of parts, a large device configuration, etc. 3D flow velocity of a microfluidic field can be obtained by applying the present invention, or by mounting the stereo optical attachment according to the present invention, without requiring processing accuracy or manufacturing accuracy of Since it is possible to perform measurement, micro object shape measurement such as particle position measurement and particle size measurement, micro object displacement measurement, and micro object deformation measurement, the practical value of the present invention is remarkable.

1 Microfluidic field imaging device 2 PC (personal computer)
3 delay generator 4 function generator 5 laser device 6 fiber scope 7 emitting unit 10 stereo optical attachment 11 imaging device 12 microscope 13 objective lens 14 laser light filter 16 prism 16a reflecting surface (second reflecting surface)
17 Mirror 17a Reflecting surface (first reflecting surface)
18 Support member 20 Base 30 Prism holding mechanism (position adjustment mechanism)
40 Horizontal position adjustment mechanism 50 Mirror holding mechanism (angle adjustment mechanism)
70 X direction adjustment mechanism (second position adjustment mechanism)
M Measurement area P Tracer particles

Claims (10)

An imaging device for imaging a particle image of a visualization fluid in a microfluidic field, a microscope optically coupled to the imaging device, a first reflecting surface disposed between the microscope and the microfluidic field, and a first A microfluidic field imaging device that acquires image data for measuring the flow velocity of the visualization fluid by the imaging device,
The angles of the plurality of first reflection surfaces, the plurality of second reflection surfaces facing each of the first reflection surfaces and arranged in the optical path of the microscope, and the first or second reflection surface are adjusted. An angle adjustment mechanism, and a position adjustment mechanism for adjusting the position of the first or second reflecting surface;
The angle and position of the reflecting surface are adjusted by the angle adjusting mechanism and the position adjusting mechanism, and the reflected light of the particles in the microfluidic field is reflected by the first and second reflecting surfaces and enters the optical path in the microscope. A microfluidic field imaging device characterized in that a plurality of images of the same particle obtained from different viewpoints are formed on a single imaging surface of the imaging device.   2. The microfluidic field imaging device according to claim 1, wherein the angle adjusting mechanism adjusts an angle of the first reflecting surface, and the position adjusting mechanism adjusts a position of the second reflecting surface.   The microfluidic field imaging device according to claim 2, further comprising a second position adjusting mechanism that adjusts a position of the first reflecting surface.   The angle adjusting mechanism adjusts an angle of the first reflecting surface with an axis perpendicular to the optical axis of the microscope as a center, and the position adjusting mechanism is configured to adjust the second direction in a direction parallel to the optical axis of the microscope. 3. The microfluidic field imaging device according to claim 2, wherein the position of the reflecting surface is adjusted, and the position of the second reflecting surface in a plane perpendicular to the optical axis of the microscope is adjusted.   The first reflecting surface is a reflecting surface of a mirror that is supported by the angle adjusting mechanism so that the angle can be adjusted, and the second reflecting surface is supported by the position adjusting mechanism so that the position can be adjusted, and in the optical path of the microscope. The microfluidic field imaging device according to any one of claims 1 to 4, wherein the microfluidic field imaging device comprises a reflecting surface of a prism or a mirror arranged.   A plurality of second reflecting surfaces are formed by a prism disposed on the optical axis of the microscope, and a first reflecting surface is formed by a plurality of mirrors spaced from the prism in a direction perpendicular to the optical axis. 5. The microfluidic field imaging device according to claim 1, wherein an optical path of reflected light reflected from the particles is formed between the prism and the mirror. 6.   The third reflecting surface that reflects illumination light of a light source toward the microfluidic field is attached to a support body of the second reflecting surface. Microfluidic field imaging device.   The microfluidic field imaging apparatus according to any one of claims 1 to 6, wherein the microfluidic field illumination light is irradiated onto the microfluidic field by coaxial incident illumination of the microscope.   The angle adjustment mechanism and / or the position adjustment mechanism includes an elastic body that elastically holds the support body of the reflecting surface, a support surface that supports the support body and restricts the direction of displacement of the support body, An adjusting tool that presses the support so that the support is displaced relative to the support surface, and the elastic body is configured so that the support is in surface contact with the support surface. The microfluidic field imaging device according to any one of claims 1 to 8, wherein the microfluidic field imaging device is elastically biased with respect to the bearing surface.   An optical attachment comprising the reflecting surface, a support for the reflecting surface, and a base for supporting the support is disposed between the microscope and the micro area, and the position of the base is determined by the imaging device and The microfluidic field imaging device according to any one of claims 1 to 9, wherein the microfluidic field imaging device is fixed to a microscope.

Images