JP2014106108A - Particle collector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a particle collector capable of measuring a temporal change of the number of particles and the like which are precipitated from a space only with one collection member.SOLUTION: A particle collector 10 includes a collection member 11 for capturing particles precipitated from a particle detection object space. A capturing surface 111 of the collection member 11 is covered with an upper case 13, and only a part of the collection surface 111 is exposed from an opening 135 of the upper case 13. Consequently, the particles in the particle detection object space are collected only in the area exposed from the opening 135 within the collection surface 111 of the collection member 11. Since the exposed area from the opening 135 of the collection surface 111 is switched over by the relative movement of the upper case 13 and the collection member 111, the particles are collected in a newly exposed area after the exposed area from the opening 135 of the collection surface 111 is switched over.

Description

  The present invention relates to a particle collecting device used for detecting the number of particles existing in a space where a collecting member is arranged.

  When a painting process, an assembly process of an optical device, or the like is performed, particles that settle from the work space adhere to the product, the quality deteriorates. On the other hand, as an apparatus for detecting the number of particles and the like, an apparatus for detecting the number of particles attached to the substrate surface has been proposed (see Patent Documents 1 and 2).

JP 2012-73039 A JP 2012-73040 A

  Here, the inventor of the present application proposes to measure temporal changes such as the number of particles settling from the work space by the methods described in Patent Documents 1 and 2 and the like. Specifically, the concentration of particles settling from the work space is determined by placing a collecting member in the work space and detecting the number of particles that have settled and adhered to the collecting surface of the collecting member. It is proposed to measure temporal changes such as (density, number).

  However, in order to measure temporal changes such as the concentration of particles in the work space using the methods described in Patent Documents 1 and 2, etc., it is necessary to replace the collection member arranged in the work space every time. Necessary and not preferred.

  In view of the above problems, an object of the present invention is to provide a particle collecting apparatus that can measure temporal changes such as the number of particles that settle from space with a single collecting member.

  In order to solve the above-described problems, the present invention is a particle collection device including a collection member having a collection surface for collecting particles, and holds the collection member with the collection surface facing upward. A collecting member holding part, and a cover having an opening partly exposing the collecting surface, and by moving the collecting member and the cover relative to each other, the collecting surface The exposure area from the opening is switched.

  In the present invention, the collection surface of the collection member is covered with a cover, and only a part of the collection surface is exposed from the opening of the cover. For this reason, the particles in the work space are collected only in the region exposed from the opening of the collection surface of the collection member. Here, since the exposure area from the opening of the collection surface is switched by the relative movement of the cover and the collection member, after the exposure area from the opening of the collection surface is switched, it is newly exposed. Particles are collected in the area. For this reason, if the number of particles for each region of the collection surface is detected, temporal changes such as the concentration (number / area) of particles that settle from the space can be measured with one collection member. .

  In this invention, it is preferable to provide the drive device which moves the said cover and the said collection member relatively, and the exposure area | region from the said opening part of the said collection surface is switched by the said drive device. According to this configuration, it is possible to automatically switch the exposure area from the opening of the collection surface.

  In this invention, it is preferable that the said drive device switches the exposure area | region from the said opening part of the said collection surface by moving the said collection member. According to such a configuration, since the cover can be fixed, the configuration of the drive device can be simplified. Further, when the particle detection device detects the number of particles on the collection surface and the like, if the entire particle collection device including the collection member is set in the particle detection device, the particle detection device is driven by the particle collection device drive device. Thus, the detection area for the collection surface can be automatically switched.

  In the present invention, the driving device may adopt a configuration in which the cover is moved to switch an exposure area from the opening of the collection surface.

  In the present invention, it is preferable that the drive device switches the exposure area from the opening of the collection surface by relatively rotating the cover and the collection member. According to this structure, even if it is a small collection member, a collection surface can be divided into areas efficiently. Moreover, if it is rotational movement, there exists an advantage that the movement area | region of a cover or a collection member may be narrow.

  In the present invention, the drive device may adopt a configuration in which the cover and the collection member are relatively linearly moved to switch the exposure area from the opening of the collection surface.

  In the present invention, it is preferable that the driving device adopts a configuration in which the cover and the collecting member are relatively moved relative to each other at regular intervals to switch an exposed area from the opening of the collecting surface. . According to such a configuration, it is possible to grasp the particle concentration of the work environment at each time without performing calculation such as correction on the detection result of the number of particles in each region of the collection surface.

  In the present invention, the drive device may adopt a configuration in which the cover and the collection member are continuously relatively moved at a constant speed to switch an exposure region from the opening portion of the collection surface.

  In this invention, it is preferable that the said collection member is provided with the parameter | index which shows the origin position at the time of switching the exposure area | region from the said opening part of the said collection surface. According to this configuration, it is possible to easily grasp the relationship between each region of the collection surface and the time during which each region is exposed from the opening.

  In the present invention, the collection surface of the collection member is covered with a cover and exposed only from the opening. For this reason, the particles in the work space are collected in a region exposed from the opening of the collection surface of the collection member. Here, since the exposure area from the opening of the collection surface is switched by the relative movement of the cover and the collection member, after the exposure area from the opening of the collection surface is switched, it is newly exposed. Particles are collected in the area. For this reason, if the number of particles or the like for each region of the collection surface is detected, it is possible to monitor temporal changes such as the concentration (number / area) of particles that settle from the space with a single collection member.

It is explanatory drawing which shows typically the structure of the particle collection apparatus which concerns on Embodiment 1 of this invention. In the particle collection apparatus which concerns on Embodiment 1 of this invention, it is explanatory drawing which shows a mode that a particle is collected by the collection surface of a collection member through the opening part of a cover. It is explanatory drawing which shows the method of monitoring the number (concentration) of the particle | grains of a workspace with time using the particle collection apparatus which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows typically the planar structure of the particle collection apparatus which concerns on Embodiment 2 of this invention. It is explanatory drawing of a particle detection apparatus. It is explanatory drawing which shows the principal part of the optical apparatus for particle detection. It is explanatory drawing of the inspection light source part of the optical apparatus for particle detection. It is a block diagram which shows the control system in a particle detection apparatus.

  With reference to the drawings, a particle collecting device to which the present invention is applied, a method for measuring a temporal change in particle concentration in a work environment, and the like will be described.

[Embodiment 1]
(Configuration of particle collecting device)
FIG. 1 is an explanatory view schematically showing a configuration of a particle collection device according to Embodiment 1 of the present invention, and FIGS. 1 (a) and 1 (b) each show a planar configuration of the particle collection device. It is explanatory drawing and explanatory drawing which shows a cross-sectional structure. In FIG. 1 (a), the area corresponding to the cover 131 is shaded upward to the right.

  In FIG. 1, a particle collection device 10 of this embodiment is a particle detection target space for the purpose of measuring the concentration (number) of particles in a particle detection target space such as a work space using a particle detection device described later. It is a device to collect particles from. For this reason, the particle collection device 10 includes a collection member 11 including a collection surface 111 that collects particles that settle from the particle detection target space, and a table that holds the collection member 11 with the collection surface 111 facing upward. And the upper case 13 provided with the cover 131 which covers the upper side of the collection surface 111, and the lower case 14 provided under the collection member 11.

  The collection member 11 is a substantially circular substrate such as a silicon wafer, and a collection surface 111 that collects particles that have settled from the air is formed by the upper surface thereof. In this embodiment, the collection member 11 is a silicon wafer, and the collection surface 111 is mirror-finished. In the present embodiment, the collecting member 11 is provided with an index 119 indicating the circumferential origin position of the collecting member 11 at one place in the circumferential direction.

  The upper case 13 protrudes outward in the radial direction from the outer edge of the cover 131, the substantially circular cover 131 covering the upper side of the collecting surface 111 of the collecting member 11, the side plate portion 132 bent downward from the outer edge of the cover 131. The connecting portion 133 is connected to the upper end portion of the protruding portion 141 that protrudes radially outward from the collecting member holding portion 12 in the lower case 14 via the hinge 140. . For this reason, the upper case 13 is rotatable about the hinge 140, the cover 131 is covered with the collection surface 111 of the collection member 11, and the cover 131 is the collection surface of the collection member 11. It is possible to switch to a standing state in which the upper part of 111 is opened. Therefore, in the flat state, the side plate portion 132 of the upper case 13 can contact the upper surface of the lower case 14 and shield the outer peripheral side of the collecting member 11. Further, in the standing state, the collecting member 11 can be installed in the collecting member holding unit 12, and the collecting member 11 can be recovered from the collecting member holding unit 12.

Here, an opening 135 is formed in the cover 131 at a position that partially overlaps the collection surface 111 of the collection member 11, and the opening 135 partially covers the collection surface 111 of the collection member 11. Exposed. In this embodiment, the opening 135 has a sector shape in which an inner arc 135a and an outer arc 135b extend within a predetermined angle range around the collection surface 111 of the collection member 11 and the center O of the collection member holding unit 12. The end portion of the inner arc 135a and the end portion of the outer arc 135b are connected by side surfaces 135c and 135d extending in the radial direction. Here, assuming that the radius of the inner arc 135a is ra, the radius of the outer arc 135b is rb, and the angle range in which the inner arc 135a and the outer arc 135b extend is θa °, the area of the opening 135 is as follows: (Π (rb) ² −π (ra) ² ) · (θa / 360)
It is represented by

  The particle collecting device 10 includes a driving device 15 that rotationally drives the collecting member 11. More specifically, the drive unit 15 includes a drive unit (not shown) including a drive source such as a motor, a transmission mechanism, a control unit, and the like inside the lower case 14, and the collecting member 11 from the lower case 14. And an upper end portion of the rotating shaft 151 is connected to a table-shaped collecting member holding portion 12 that is driven to rotate integrally with the rotating shaft 151. In this embodiment, the driving device 15 intermittently rotates the rotating shaft 151 and the collecting member holding part 12 around a certain axis L around the axis L passing through the center O of the collecting member 11 (around the axis L of the rotating shaft 151). By doing so, the collection member 11 is intermittently rotated and moved at regular intervals, and the exposed region from the opening 135 of the collection surface 111 is switched in the circumferential direction. The control of the driving device 15 controls the rotation speed, the stop time, and the like during the intermittent rotation based on settings from the outside.

  Thus, in the particle collection device 10 of the present embodiment, the cover 131 (upper case 13) is fixed, whereas the collection member 11 is rotationally driven around the axis L by the drive device 15, The exposed area from the opening 135 of the collection surface 111 is switched in the circumferential direction.

(How to use the particle collecting device 10)
FIG. 2 is a diagram illustrating how particles are collected on the collection surface 111 of the collection member 11 through the opening 135 of the upper case 13 in the particle collection device 10 according to Embodiment 1 of the present invention. FIG. FIG. 3 is an explanatory diagram showing a method of monitoring the number (concentration) of particles in the particle detection target space over time using the particle collection device 10 according to Embodiment 1 of the present invention. ) And (b) are explanatory diagrams showing the relationship between the time passage and the angular position of the region exposed from the opening 135 of the upper case 13 in the collecting surface 111 of the collecting member 11, and the time passage, respectively. It is explanatory drawing which shows a mode that the number (density | concentration) of the particle | grains captured by the collection surface 111 with it changes.

  When monitoring the concentration of particles in the particle detection target space using the particle collection device 10 shown in FIG. 1, first, the particle collection device 10 is arranged at a predetermined position in the particle detection target space, and the driving device 15 is operated. . In such an initial state, the collection member 11 is at the origin position with reference to the index 119, and a region of the collection surface 111 closest to the index 119 is exposed from the opening 135 of the upper case 13.

  In this state, as shown in FIG. 2, the particles floating in the particle detection target space settle. At this time, the particles P1 that have settled in the region where the opening 135 of the upper case 13 is located pass through the opening 135 to the region exposed from the opening 135 on the collection surface 111 of the collection member 11. Settling and collecting. The collection amount of the particles P1 is proportional to the particle concentration in the particle detection target space. On the other hand, the particles P2 that have settled in the region where the opening 135 is not formed in the cover 131 of the upper case 13 are captured by the upper surface of the cover 131 and do not pass through the opening 135. It is not collected on the collecting surface 111 of the collecting member 11.

  From this state, as shown in FIG. 3A, when a certain sampling time (stop time t1) has elapsed, the driving device 15 rotates around the axis L passing through the center O of the collecting member 11 (the axis of the rotating shaft 151). By rotating the rotation shaft 151 and the collection member holding portion 12 around the rotation member, the collection member 11 is rotated by a predetermined angle, and the exposed region from the opening 135 of the collection surface 111 is switched in the circumferential direction. Thereafter, such driving is executed at every fixed stop time t1. For this reason, on the collection surface 111 of the collection member 11, the exposure area | region from the opening part 135 moves in the circumferential direction for every progress of time, and as shown to FIG. In this case, particles proportional to the particle concentration in the particle detection target space are collected. Therefore, if the number of particles in each region obtained by dividing the collection surface 111 of the collection member 11 in the circumferential direction is detected by a particle detection device or the like described later, the temporal change in the particle concentration in the particle detection target space is measured. can do.

(Main effects of this form)
As described above, in the particle collection device 10 of this embodiment, the collection surface 111 of the collection member 11 is covered with the cover 131, and only a part of the collection surface 111 is opened from the opening 135 of the cover 131. Exposed. For this reason, the particles in the particle detection target space are collected only in the region exposed from the opening 135 on the collection surface 111 of the collection member 11. Here, since the exposure area from the opening 135 of the collection surface 111 is switched by the relative movement of the cover 131 and the collection member 11, the exposure area from the opening 135 of the collection surface 111 is switched. The particles are collected in the newly exposed area. Therefore, if the number of particles or the like for each region of the collection surface 111 is detected, temporal changes such as the concentration (number / area) of particles that settle from the particle detection target space by one collection member 11 Can be monitored.

  In addition, since the collection member 11 is provided with an index 119 indicating the origin position when switching the exposure area from the opening 135 of the collection surface 111, each area of the collection surface 111 and each area are The relationship with the time exposed from the opening 135 can be easily grasped.

  Further, the particle collection device 10 of the present embodiment is provided with a drive device 15 for moving the cover 131 and the collection member 11 relative to each other, and the drive device 15 exposes the collection surface 111 from the opening 135. The area is automatically switched. For this reason, it is possible to automatically collect particles settled from the particle detection target space at each time, and it is possible to easily monitor temporal changes such as the concentration (number) of particles. Further, the drive device 15 can keep the cover 131 fixed in order to move the collection member 11. Therefore, the configuration of the driving device 15 can be simplified. In addition, when detecting the number of particles on the collection surface 111 with a particle detection device or the like, which will be described later, if the particle distribution on the entire collection surface 111 cannot be measured by a single detection process, the collection member 11 is used. When the entire particle collecting device 10 including the particle collecting device 10 is set in the particle detecting device, the particle collecting device driving device 15 can automatically switch the detection area for the collecting surface 111 by the particle detecting device.

  Moreover, since the drive device 15 rotates and moves the collection member 11, even if it is a small collection member 11, the collection surface 111 can be divided into regions efficiently. Moreover, if it is rotational movement, there exists an advantage that the movement area | region of the collection member 11 may be narrow.

  Furthermore, the drive device 15 switches the exposure region from the opening 135 of the collection surface 111 by relatively moving the upper case 13 and the collection member 11 intermittently at regular intervals. For this reason, it is possible to grasp the particle concentration of the working environment at each time without performing correction or the like on the detection result of the number of particles in each region of the collection surface 111.

[Embodiment 2]
FIG. 4 is an explanatory view schematically showing a planar configuration of the particle collecting apparatus according to Embodiment 2 of the present invention. Since the basic configuration of this embodiment is the same as that of Embodiment 1, common portions are denoted by the same reference numerals and description thereof is omitted. In FIG. 4, a region corresponding to the cover 131 is shaded upward to the right.

  In FIG. 4, the particle collection device 10 of the present embodiment also collects the collection member 11 having the collection surface 111 for collecting the settled particles and the collection surface 111 upward as in the first embodiment. A table-shaped collecting member holding portion (not shown) for holding the collecting member 11, an upper case 13 having a circular cover 131 covering the upper side of the collecting surface 111, and a lower portion of the collecting member 11 are provided. And a driving device (not shown) is provided using the inside of the lower case 14 and the like. The cover 131 is formed with an opening 135 that partially exposes the collection surface 111 of the collection member 11.

  Regarding the particle collecting apparatus 10 configured as described above, in the first embodiment, the cover 131 (upper case 13) is fixed and the collecting member 11 is rotationally driven by the driving device 15. Then, the collection member 11 and the collection member holding part are fixed. Therefore, in the upper case 13 of the present embodiment, a frame-like support portion 137 that rotatably supports the cover 131 is provided around the circular cover 131, and the connecting portion 133 of the upper case 13 is driven. A transmission mechanism is configured to transmit a rotational driving force from a device (not shown) to the cover 131 and rotate the cover 131 around an axis L passing through the center O of the collecting member 11. For this reason, in the particle collection device 10 of this embodiment, the cover 131 is rotationally driven around the axis L by the drive device 15 so that the exposed region from the opening 135 of the collection surface 111 is switched in the circumferential direction. It has become. Further, the driving device is configured to switch the exposure region from the opening 135 of the collection surface 111 by relatively moving the cover 131 of the upper case 13 intermittently at regular intervals.

  Also in the particle collecting apparatus 10 having such a configuration, as in the first embodiment, if the number of particles for each region of the collection surface 111 is detected, the single collection member 11 sinks from the particle detection target space. It is possible to monitor temporal changes such as the concentration (number / area) of particles to be performed.

[Embodiment 3]
In the first and second embodiments, the driving device 15 intermittently relatively moves the upper case 13 and the collection member 11 at regular intervals. However, the drive case 15 moves the upper case 13 and the collection member 11 at a constant speed. The relative movement may be continuously performed. Even in such a configuration, if the number of particles in each region of the collection surface 111 is detected, it is possible to monitor temporal changes in the particle concentration at each time. Further, if the calculation is performed on the detection result of the number of particles in each region of the collection surface 111, the particle concentration at each time can be grasped.

[Embodiment 4]
In the said Embodiment 1, 2, although the collection member 11 was circular by planar view and was the structure which moves the exposure area | region from the opening part 135 of the collection surface 111 in the circumferential direction, the collection surface 111 The exposed area from the opening 135 may be moved spirally on the collection surface 111. Such a configuration is, for example, in Embodiment 1 by reducing the radial dimension of the opening 135 and moving the radial position of the opening 135 in the radial direction in conjunction with the rotation of the collection member 11. Can be realized. According to this structure, even if it is the small collection member 11, the collection surface 111 can be divided | segmented into more area | regions.

[Embodiment 5]
In the said Embodiment 1-4, although the collection member 11 was circular by planar view, the polygon etc. may be sufficient as the collection member 11 by planar view.

[Embodiment 6]
In the first and second embodiments and the like, the collection member 11 has a circular shape in plan view and is configured to move the exposed area from the opening 135 of the collection surface 111 in the circumferential direction. 11 may be configured to use a belt-like member in plan view and linearly move the exposed region from the opening 135 of the collection surface 111.

[Configuration example of particle detector]
After collecting the particles on the collecting member 11 using the particle collecting device 10 described above, the particle distribution on the collecting surface 111 is measured by the particle detecting device, and the particles in each region of the collecting surface 111 are measured. Measure the number of Therefore, it is possible to measure the concentration of particles in the particle detection target space at the time corresponding to each region in the circumferential direction of the collection surface 111. The detection method of the particle detection device is not particularly limited, such as a microscopic method, but in this embodiment, the particle detection device described below is used. Since the particle detection apparatus illustrated here is the same as that described in Japanese Patent Application Laid-Open No. 2012-73039, its configuration and principle will be briefly described. In the following description, the case where a circular member in plan view is used as the collecting member 11 is illustrated, but the basic case also when the strip-like collecting member 11 described in the sixth embodiment is used. The number of particles in each region of the collection surface 111 can be measured by the same principle.

(Overall configuration of particle detector)
FIG. 5 is an explanatory diagram of the particle detection device, and FIGS. 5A and 5B are respectively an explanatory diagram illustrating a configuration of the entire particle detection device and a plan view of the collection member 11 to be inspected for particles. It is. FIG. 6 is an explanatory view showing a main part of the optical device for particle detection. FIG. 7 is an explanatory diagram of the inspection light source unit 31 of the particle detection optical device. FIGS. 7A, 7B, and 7C are planes showing a planar layout of the inspection light source unit 31, respectively. It is explanatory drawing which shows the optical layout of the light source part 31 for a test | inspection, and a mode that the test | inspection light L is irradiated to the collection surface 111. In FIG. 7, the reflecting mirror 26 is removed.

  As shown in FIG. 5, the particle detection device 1 includes a particle detection optical device 2, and a computer 3 including a display unit 3a and an input unit 3b such as a keyboard and a mouse. The computer 3 is communicably connected to the particle detection optical device 2.

  The particle detection optical device 2 includes a device main body 21 provided with a switch 21a and a lamp 21b on the front side, and an optical system storage portion 22 that stands up on the rear side of the device main body 21 and has an upper portion protruding forward. doing. On the upper surface of the apparatus main body 21, a sample stage 23 is provided one step higher. The sample stage 23 is provided with a circular plane inspection region 24 on the upper end surface thereof, and the collection member 11 to be inspected for particles P is arranged in the plane inspection region 24, and the collection member 11 is captured. The collecting surface 111 is located on the planar inspection region 24. On the side of the sample stage 23, an illuminance reference member 25 is provided (see FIG. 7). In front of the sample stage 23 and the illuminance reference member 25, a reflecting mirror 26 (reflective member) that covers the front part of the sample stage 23 and the illuminance reference member 25 is attached. In front of the reflecting mirror 26, a double revolving door 27 is provided between the apparatus main body 21 and the optical system storage unit 22 so as to switch between a state in which the sample table 23 is enclosed and an open state. The revolving door 27 has a light shielding property, and the inside of the revolving door 27 with the revolving door 27 in a closed state is a measurement chamber 28 in which light is blocked from the outside. In this embodiment, the reflecting mirror 26 has a mirror surface as a reflecting surface.

  As shown in FIGS. 6 and 7, the sample stage 23 has a circular recess 231 in the center, and the collecting member 11 is disposed in the circular recess 231. The circular concave portion 231 has an inner diameter corresponding to the outer diameter of the collecting member 11. When the collecting member 11 is arranged inside the circular concave portion 231, the collecting member 11 is positioned in the radial direction, and the collecting member 11. And the center 24a of the planar inspection region 24 coincide with each other. The circular recess 231 has a depth corresponding to the thickness of the collection member 11. When the collection member 11 is disposed inside the circular recess 231, the collection surface 111 and the upper end surface of the sample stage 23 are arranged. 23a matches in the height direction. The upper end opening of the circular recess 231 defines the plane inspection region 24.

  The optical system storage unit 22 (see FIG. 5) includes an imaging unit 29 and an illumination device 30 above the sample stage 23. The imaging unit 29 includes a CCD camera in which a plurality of pixels are arranged in a matrix, and is arranged downward so as to face the center 24 a of the planar inspection region 24. The illumination device 30 is disposed downward so as to face the planar inspection region 24, and irradiates divergent light that can irradiate the entire planar inspection region 24. Further, the optical system storage unit 22 includes an inspection light source unit 31 that irradiates the planar inspection region 24 and the illuminance reference member 25 with the inspection light L (see FIG. 7) behind the sample stage 23.

  When detecting the particles P adhering to the collecting member 11, in the optical device 2 for particle detection, the collecting member 11 is set on the sample stage 23 and the rotary door 27 is closed. Next, the inspection light L is irradiated from the inspection light source unit 31 to the planar inspection region 24, and the scattered light of the inspection light L scattered by the particles P adhering to the collection surface 111 is imaged by the imaging unit 29. . When the image data is acquired in this way, the particle detection optical device 2 transmits the image data to the computer 3. The computer 3 detects the number and size of the particles P on the collecting member 11 based on the received image data. Further, the computer 3 displays the detection result of the particles P together with the received image data on the display unit 3a.

  When observing the particles P adhering to the collection member 11, in the particle detection optical device 2, the collection member 11 is set on the sample stage 23 and the rotary door 27 is opened. Next, the illumination device 30 illuminates the planar inspection region 24, irradiates the planar inspection region 24 with the inspection light L from the inspection light source unit 31, and scatters the inspection light L scattered by the particles P on the collection surface 111. The light is imaged by the imaging unit 29. When the image data is acquired in this way, the particle detection optical device 2 transmits the image data to the computer 3. The computer 3 displays the received image data on the display unit 3a.

(Configuration of inspection light source unit 31)
As shown in FIGS. 5, 6, and 7, the inspection light source unit 31 emits a light emitting diode 41 as a light source, a holder 42 that holds the light emitting diode 41, and an inspection light L toward the planar inspection region 24. In addition, a scanning device 43 for scanning along the plane inspection region 24 is provided.

  The light emitting diode 41 emits green divergent light. As shown in FIGS. 7B and 7C, the scanning device 43 includes a scanning mirror 432 and a drive device (not shown) that rotates the scanning mirror 432 around its central axis 431. The scanning mirror 432 is a regular octagonal prismatic polygon mirror having a central axis 431 oriented in a direction perpendicular to the planar inspection region 24 and is positioned slightly above the planar inspection region 24.

  A convex lens 44 (convergence lens) is accommodated in the holder 42, and divergent light emitted from the light emitting diode 41 is converted into convergent light by the convex lens 44. As shown in FIG. 7C, the convergent light proceeds as convergent light even after being reflected by the scanning mirror 432, and is irradiated as the inspection light L toward the planar inspection region 24. The inspection light L forms a focal point F at a position where the distance from the light source is optically farthest in the planar inspection region 24. Further, the inspection light L is reflected by the scanning mirror 432 rotating around the central axis 431, thereby collecting the collection surface 111 along the planar inspection region 24 as indicated by an arrow S in FIG. The entire collection surface 111 is irradiated from the side obliquely upward.

(Configuration of illuminance reference member)
The illuminance reference member 25 is a glass plate or the like having fine irregularities on the surface 25a, and the surface 25a has light scattering properties. The illuminance reference member 25 is disposed such that the surface of the illuminance reference member 25 is lower than the collection surface 111 disposed in the planar inspection region 24 at a position outside the planar inspection region 24. Accordingly, the inspection light L from the inspection light source unit 31 is applied to the illuminance reference member 25 with an illuminance lower than that of the planar inspection region 24.

  The reflecting mirror 26 is disposed on the opposite side of the scanning mirror 432 across the center 24a of the planar inspection region 24, and covers the front side portion of the planar inspection region 24 from obliquely upward from the front. An inner reflection surface 26 a facing the flat inspection region 24 side in the reflecting mirror 26 is an arc surface defined with the center 24 a of the flat inspection region 24 as the center. The reflecting mirror 26 reflects the reflected light of the inspection light L reflected by the collection surface 111 of the collection member 11 disposed in the planar inspection region 24 to the collection surface 111 side by the reflection surface 26a.

(Control system configuration)
FIG. 8 is a block diagram showing a control system in the particle detection apparatus 1. In FIG. 8, in the particle detection device 1, the computer 3 operates based on a program stored in the memory in advance, and an optical device control unit that controls the particle detection optical device 2 based on a command from the input unit 3 b. 51, a receiving unit 52 that receives image data transmitted from the particle detection optical device 2, an image processing unit 53 that detects particles P based on the image data, and particles detected based on the image data and the image data The display control part 54 which displays the detection result of P on the display part 3a is provided. The optical device control unit 51 controls the imaging unit 29, the illumination device 30, and the inspection light source unit 31 based on the command input from the input unit 3b.

  In this example, when the “particle detection command” is input from the input unit 3b after the collection member 11 is set on the sample stage 23 and the rotary door 27 is closed, the inspection light source unit 31 and the imaging unit 29 are turned on. Driving control is performed, the inspection light L is irradiated from the inspection light source unit 31 to the planar inspection region 24, and the scattered light of the inspection light L scattered by the particles P on the collection surface 111 is imaged by the imaging unit 29. Then, the acquired image data is transmitted from the imaging unit 29 to the computer 3. In the “particle detection command”, the illumination device 30 is not turned on, and the imaging by the imaging unit 29 is performed in the “dark field state”. The dark field state means a state in which light other than the inspection light L is not irradiated on the measurement chamber 28.

  Further, when a “particle observation command” is input from the input unit 3b after the collection member 11 is set on the sample stage 23 and the rotary door 27 is closed, the illumination device 30, the inspection light source unit 31, and the imaging The unit 29 is driven and controlled, the illumination device 30 illuminates the planar inspection region 24, the inspection light L is irradiated from the inspection light source unit 31 to the planar inspection region 24, and the particles P on the collection surface 111 are captured by the imaging unit 29. The scattered light of the inspection light L scattered by is photographed. Then, the acquired image data is transmitted from the imaging unit 29 to the computer 3. In the “particle observation command”, the illumination device 30 is turned on, and the imaging by the imaging unit 29 is performed in the “bright field state”. The bright field state means a state where light other than the inspection light L is irradiated on the planar inspection region 24. Note that, when a “particle observation command” is input, imaging may be performed without driving the inspection light source unit 31. That is, the inspection light L is not irradiated from the inspection light source unit 31 to the planar inspection region 24, and the scattered light of the diverging light of the illumination device 30 scattered by the particles P on the collection surface 111 is captured by the imaging unit 29. You may shoot.

  Here, the image data transmitted from the particle detection optical device 2 to the computer 3 is two-dimensional image data, in which coordinates indicating pixel positions are associated with luminance values of the respective pixels. The receiving unit 52 receives the image data from the particle detecting optical device 2 and stores it in the storage device 55. The image data is output to the image processing unit 53 and the display control unit 54.

  The image processing unit 53 specifies the size of the particle P based on the region extracted by the region extracting unit 531 and the region extracting unit 531 that extract the scattered light region from the image data received from the particle detection optical device 2. A particle identification unit 532 and a counting unit 533 that counts the number of particles P identified by the particle identification unit 532 are provided. Here, the region extraction unit 531, the particle identification unit 532, and the counting unit 533 operate when the “particle detection command” is input, and when the “particle observation command” is input, Do not work.

  The area extracting unit 531 includes various memories and stores a threshold value input in advance from the input unit 3b. The threshold value is a lower limit value for recognizing that the particle P exists in the intensity of the scattered light of the inspection light L irradiated to the particle P. The region extraction unit 531 processes the image data using the image data input from the imaging unit 29 and a threshold value, and obtains a high-luminance pixel region in which pixels having luminance values equal to or higher than the threshold value are grouped. At the same time, the position of the high luminance pixel region, the number of pixels included in the high luminance pixel region, and the luminance value of each pixel are extracted as high luminance pixel information and output to the particle specifying unit 532. The high luminance pixel region extracted by the region extraction unit 531 corresponds to the particle P on a one-to-one basis.

  Here, the region extraction unit 531 corrects the luminance and threshold value of each pixel based on the intensity of the scattered light of the inspection light L irradiated on the illuminance reference member 25. That is, since the amount of light emitted from the light emitting diode 41 used as the light source may fluctuate and affect the luminance of each pixel, the luminance and threshold value of each pixel are corrected. In this example, the value obtained by dividing the actual luminance of each pixel by the detected value of scattered light from the illuminance reference member 25 is treated as the luminance of the pixel. For this reason, the threshold value is also set to a value corresponding to a value obtained by dividing the actual luminance of each pixel by the detected value of scattered light from the illuminance reference member 25.

  The particle identification unit 532 is attached to the collection surface 111 based on the position of the high luminance pixel area, the total number of pixels included in the high luminance pixel area, and the luminance value included in the high luminance pixel information. The position and size of the particle P are specified. That is, if the size of the particle P is large, the number of pixels existing in the high luminance pixel region is large and the luminance is high. Therefore, the size of the particle P is specified based on the number of pixels existing in the high luminance pixel region and the luminance. be able to.

  In addition, the particle specifying unit 532 classifies each specified particle P by size. In this example, for example, it is classified into 30 μm or more and less than 60 μm, 60 μm or more, less than 90 μm, and 90 μm or more. Further, the particle identification unit 532 outputs the position and size of the particle P and the classification result to the counting unit 533 as the particle identification information.

  The counting unit 533 includes a plurality of counters, and counts the number of particles P by incrementing the counter value by 1 each time the particle identification information is received. Further, the number of particles P of each classification is counted based on the classification result included in the particle identification information. Further, the particle specifying information, the total number of counted particles P and the number of classified particles P are output to the display control unit 54.

  If the region extraction unit 531 cannot detect the high luminance pixel region, the region extraction unit 531 outputs zero information indicating that no high luminance pixel region exists to the particle identification unit 532. In this case, since the particle identification information is not output from the particle identification unit 532, the counting unit 533 does not count the particles P.

  When the “particle detection command” is input, the display control unit 54 displays the image data from the reception unit 52 on the display unit 3a, and also includes particles including the position, size, and classification result of each particle P. Specific information, the total number of particles P, and the number of particles P of each classification are displayed on the display unit 3a. Here, the image data displayed on the display unit 3a is acquired in the dark field state.

  Further, when the “particle observation command” is input, the display control unit 54 displays only the image data from the reception unit 52 on the display unit 3a. Here, the image data displayed on the display unit 3a is acquired in the bright field state.

(Particle detection operation)
The particle detection device 1 is used for monitoring the particles P in the area where the collection member 11 is disposed. More specifically, after the collection member 11 is arranged in a predetermined area, it is collected and monitored for the particles P adhering to the collection member 11, thereby existing in the area where the collection member 11 was arranged. The number and size of particles P to be obtained are obtained. In addition, the index 119 attached to the collection member 11 is set as the origin position, and the number of particles P for each region on the collection member 11 is detected. The number of particles P for each region corresponds to the particle concentration at each time in the particle detection target space.

  When detecting the particles P, first, the collection member 11 is set on the sample stage 23, that is, the collection surface 111 of the collection member 11 is arranged on the planar inspection region 24, and the rotary door 27 is closed. And Thereafter, a “particle detection command” is input from the input unit 3b. Thereby, irradiation of the inspection light L from the inspection light source unit 31 to the planar inspection region 24 is started, and imaging by the imaging unit 29 is started. At that time, the illumination device 30 is turned off (dark field imaging step).

  In the dark field imaging step, when the imaging unit 29 acquires scattered light generated by the particles P as image data and transmits it to the computer 3, the receiving unit 52 stores the image data in the storage device 55. The receiving unit 52 outputs the image data to the display control unit 54 and also outputs the image data to the region extraction unit 531. The area extraction unit 531 obtains a high-luminance pixel area, extracts the position of the high-luminance pixel area, the number of pixels included in the high-luminance pixel area, and the luminance of each pixel as high-luminance pixel information, and supplies the extracted data to the particle identification unit 532. Output.

  In the particle specifying unit 532 to which the high luminance pixel information is input, each particle attached to the collection surface 111 based on the position of the high luminance pixel region, the number of pixels included in the high luminance pixel region, and the luminance of each pixel. Specify the position and size of P. Moreover, each particle P is classified according to size. Then, the position and size of each particle P and the classification result are output to the measurement unit as particle identification information.

  The counting unit 533 to which the particle identification information is input counts the total number of particles P and the number of particles P of each classification, and outputs them together with the particle identification information to the display control unit 54. Therefore, the display control unit 54 includes the image data. The particle specifying information including the position and size of each particle P and the classification result, the total number of particles P, and the number of particles P of each classification are displayed on the display unit 3a.

  Next, when the user of the particle detection device 1 inputs a “particle observation command” to the input unit 3 b of the computer 3, the illumination device 30 is turned on, and the imaging unit 29 images the collection surface 111 in a bright field state. At that time, the inspection light L from the inspection light source unit 31 is in a state of scanning the planar inspection region 24. (Bright-field imaging process).

  In the bright field imaging step, when the imaging unit 29 acquires scattered light generated by the particles P as image data and transmits it to the computer 3, the reception unit 52 stores and holds this image data in the storage device 55. The receiving unit 52 outputs the image data to the display control unit 54, and the display control unit 54 displays the image data on the display unit 3a. That is, since the particle P is not specified in the bright field imaging process, only the image data is displayed on the display unit 3a by the display control unit 54.

  Here, in the bright field imaging step, an image of the large-sized particle P is displayed on the display unit 3a, so that the outer shape of the large-sized particle P can be observed. Therefore, it is possible to determine what the large size particle P is derived from. Further, since the light emitting diode 41 continues to be lit during the bright field imaging process, the outer shape of the small particle P cannot be observed, but the scattered light from the small particle P is displayed on the display unit 3a. Is done.

  In such a particle detection operation, if the intensity of the inspection light L and the sensitivity of the imaging unit 29 are set corresponding to the particles P with low brightness of scattered light, the number of small particles P or The size can be detected. In this case, the detection sensitivity is saturated at the brightness level of the scattered light from the large particles P, and the outer shape of the large particles P cannot be detected, but the outer shape of the large particles P can be detected in the bright field imaging process. . Accordingly, the particle P having a small size can be detected with a simple configuration, and the outer shape of the particle P having a large size can be detected.

  In the particle detection apparatus 1 described with reference to FIGS. 5 to 8, the particles on the entire collection surface 111 of the collection member 11 are measured in a lump, but the collection of the collection member 11 is performed. The particle detection apparatus 1 that divides the surface 111 into a plurality of regions and sequentially measures particles in each region may be used.

DESCRIPTION OF SYMBOLS 1 Particle detection apparatus 10 Particle collection apparatus 11 Collection member 12 Collection member holding part 13 Upper case 14 Lower case 15 Drive apparatus 111 Collection surface 119 Indicator 131 Cover 135 Opening part P, P1, P2 Particle

Claims (9)

In a particle collecting apparatus having a collecting member having a collecting surface for collecting particles,
A collecting member holding part for holding the collecting member with the collecting surface facing upward;
A cover having an opening partly exposing the collection surface;
Have
The particle collection device, wherein an exposure area of the collection surface from the opening is switched by relatively moving the collection member and the cover. A drive device for relatively moving the cover and the collecting member;
The particle collection device according to claim 1, wherein an exposure area of the collection surface from the opening is switched by the driving device.   The particle collecting apparatus according to claim 2, wherein the driving device moves the collecting member to switch an exposed region of the collecting surface from the opening.   The particle collecting device according to claim 2, wherein the drive device switches the exposure region from the opening of the collection surface by moving the cover.   5. The drive device according to claim 2, wherein the cover and the collection member are rotated relative to each other to switch an exposure region of the collection surface from the opening. The particle collection apparatus as described in.   5. The drive device according to claim 2, wherein the exposure region of the collection surface from the opening is switched by relatively moving the cover and the collection member linearly. The particle collection apparatus as described in.   7. The drive device according to claim 2, wherein the drive device switches the exposure area from the opening of the collection surface by intermittently moving the cover and the collection member at regular intervals. The particle collection apparatus as described in any one of Claims.   7. The drive device according to claim 2, wherein the cover and the collecting member are continuously moved relative to each other at a constant speed so as to switch an exposed area from the opening of the collecting surface. The particle collecting apparatus according to claim 1.   The said collection member is provided with the parameter | index which shows the origin position at the time of switching the exposure area | region from the said opening part of the said collection surface, It is any one of Claim 1 thru | or 8 characterized by the above-mentioned. Particle collection device.

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