JP2005181085A - Optical trap probe near-field light microscope and near-field optical detection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical trap probe near-field light microscope, capable of obtaining a high S/N ratio in a near-field light detection signal captured stably and detected by an optical trap probe, and to provide a near-field optical detection method. <P>SOLUTION: The optical trap probe near-field light microscope is constituted so that the optical trap probe (15), provided with a metal member (17) in the whole or a part of the surface of a dielectric microstructure (16), is used to perform positional scanning after the capture due to condensed luminous flux to be allowed to approach the surface of an object to be inspected to detect scattered light produced, by scattering the condensed luminous flux by both of the optical trap probe and the surface of a specimen or a part of scattered light passed through the specimen. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical trap probe near-field light microscope apparatus and a near-field light detection method, and more particularly to a nano-order measurement / processing technique using a scanning near-field optical microscope (hereinafter abbreviated as SNOM).

  In recent years, measurement and processing of nano-orders have been carried out by scanning probe microscopes (hereinafter abbreviated as SPM), including scanning tunneling microscopes (hereinafter abbreviated as STM) and scanning atomic force microscopes (hereinafter abbreviated as AFM). It has been broken. SNOM, which is in this SPM and can detect optical characteristics in a minute region below the diffraction limit, is used as a measuring device and an evaluation device in various fields such as biotechnology. In this SNOM, a fine structure having a dimension smaller than the diffraction limit is used as a probe, and near-field light is generated in the vicinity thereof by illuminating the probe tip. By scanning the probe on the sample surface in this state, the near-field light scattered by the electromagnetic interaction between the near-field light localized near the probe and the sample surface or near-field light transmitted through the sample surface is detected. Thus, optical information on the sample surface can be obtained. In addition, research and development of optical recording devices and microfabrication devices using such SNOM technology is also underway.

  This SNOM can be roughly classified into an aperture type and a scattering type depending on the form of the probe for generating or detecting near-field light. As a typical example of the former, the end portion of the optical fiber is sharpened and then covered with a light shielding film, and a part of the fiber core that is formed by exposing a part of the fiber core is used. In addition, a typical example of the latter is a sharpened metal probe, for example, Non-Patent Document 2. As another representative example of the latter, Non-Patent Document 3 describes SNOM using laser trapped particles as a probe. In the said nonpatent literature 3, the fine structure of glass is observed using the gold | metal fine particle of a smaller diameter (40 nm) as a probe with the laser of wavelength 1064nm. The SNOM using the laser trapped particles as a probe will be described below with reference to the drawings.

  FIG. 10 is a schematic cross-sectional view showing the configuration of the laser trap SNOM. In the figure, light oscillated from a laser light source 1 for optical trapping is collimated by a lens 2, and is turned back by a dichroic mirror 3 that selectively reflects light having the same wavelength as the light oscillated from the laser light source 1. Is incident on the objective lens 4 immersed in the lens. The light condensed by the objective lens 4 captures the fine particles 5 dispersed in the pure water 14. In the experimental system of Non-Patent Document 3, since the trapped fine particles (diameter 40 nm) are sufficiently small with respect to the trap light wavelength (1064 nm), the fine particles are three-dimensionalized by a gradient force based on the light intensity distribution near the focal point of the trap light. Has been captured. On the other hand, by utilizing the fact that the force acting on the fine particles 5 is the direction attracted to the focal position of the objective lens 4, the fine particles 5 are placed on the surface of the sample 9 by arranging the focal position near the surface of the sample 9. You can always keep in contact. The laser light oscillated from the near-field light generating laser light source 6 is applied to the collimating lens 7, the beam splitter 8, and the objective lens 4 with respect to the fine particles 5 captured by the laser light from the optical trap laser light source 1. And near-field light is generated around the fine particles 5. The light scattered by the near-field light interacting with the surface of the sample 9 enters the detector 13 through the objective lens 4, the condenser lens 11, and the pinhole 12 for removing disturbance light. Using the scanning stage 10 on which the sample 9 is mounted, the sample 9 is scanned relative to the fine particles 5, and a signal is obtained by the above-described near-field light detection method at each scanning position. Thus, near-field light information of the entire surface of the sample 9 can be obtained.

  In SNOM using such laser trapped particles as a probe, the sample size and shape can be made constant without causing damage to each other due to collision between the sample and the probe compared to SNOM using conventional probes. Therefore, there is an advantage that the reproducibility of the acquired data is high and the particle can be kept in contact with the sample surface at all times, so that the distance control between the probe and the sample is unnecessary. However, it depends on variations in the size and shape of available particles.

  However, in the SNOM of Non-Patent Document 3 using gold fine particles trapped by a laser as a probe, it is necessary to further reduce the diameter of the particles in consideration of higher resolution. However, as the diameter is reduced, the thermal energy of the trap light increases. Increased Brownian motion causes an increase in position error. In general, in order to trap stably (with little variation in capture position), the output of trap light must be improved. However, as the particle size decreases, the capture power per unit light output decreases. The variation of the capture position due to Brownian motion and the ratio of deviation amount increase. Therefore, the S / N of the near-field light detection signal is reduced.

Therefore, Patent Document 1 proposes an SNOM that can detect the distance between the probe and the sample by detecting the return light from the particles by the critical angle method.
APPI.Phys.Lett.Vol.40,651 (1984) Opt.Lett.Vol.19,159 (1994) Opt.Lett.Vol.22,1663 (1997) JP 2002-22640 A

  However, since Patent Document 1 is an SNOM using a single particle as a probe, the same problem as in the above-mentioned Non-Patent Document 3 is caused by the reduction in particle diameter. In addition, a “critical angle method” has been proposed that obtains displacement information of the trapped optical axis direction of particles by detecting changes in the amount of return light. Obtaining is considered difficult in practice.

  The present invention is intended to solve these problems, and an optical trap probe capable of stably capturing an optical trap probe and obtaining a high S / N in a detected near-field light detection signal. An object is to provide a near-field optical microscope apparatus and a near-field light detection method.

  In order to solve the above problems, the optical trap probe near-field optical microscope apparatus of the present invention includes an optical trap probe, a condensed light beam generation means, an optical trap probe scanning means, and a scattered light detection means. The optical trap probe is provided with a metal member on the whole or a part of the surface of the dielectric microstructure. The condensed light beam generating means generates a condensed light beam of laser light to capture the optical trap probe. The optical trap probe scanning means is a means for bringing the optical trap probe close to the surface of the subject in a state where the optical trap probe is captured by the condensed light beam by the condensed light beam means. Furthermore, the scattered light detection means detects scattered light generated by the scattered light beam being scattered by both the optical trap probe and the surface of the subject, or part of the scattered light that has passed through the subject. Therefore, the optical trap probe can be stably captured, high S / N can be obtained in the detected near-field light detection signal, and internal physical property information of the subject can be obtained.

  Further, the optical trap probe near-field optical microscope apparatus of the present invention includes a generating unit that generates a laser beam having a different oscillation wavelength from the condensed beam by the focused beam unit, and a beam incident that causes the beam to enter the optical trap probe. And detecting means for detecting the light beam reflected and scattered by the optical trap probe separately from the reflected light or scattered light of the condensed light beam for capturing the optical trap probe. Therefore, a stable S / N can be obtained in the near-field light detection signal.

  Further, the optical trap probe near-field optical microscope apparatus according to the present invention includes a generating unit that generates a laser beam having a different intensity modulation frequency from the focused beam by the focused beam unit, and a beam that enters the beam into the optical trap probe. Incident means and detection means for detecting the light beam reflected and scattered by the optical trap probe separately from the reflected or scattered light of the condensed light beam for capturing the optical trap probe. Therefore, a stable S / N can be obtained in the near-field light detection signal.

  In addition, by providing a means for changing the condensed light beam by the condensed light beam means into a light beam whose cross-sectional light intensity distribution perpendicular to the optical axis has a hollow shape, stable capture of the optical trap probe and efficient near-field light can be achieved. Can be generated automatically.

  In addition, since the dielectric microstructure is spherical, near-field light detection with high S / N becomes possible.

  In addition, the near-field light detection signal can be increased when the metal member is either Au or Ag.

  Furthermore, by providing means for moving the focal position of the collected light beam for capturing the optical trap probe in a direction perpendicular to the optical axis of the collected light beam, near-field light at each position on the surface of the subject. The signal can be detected.

  Further, by providing means for driving the subject in a three-dimensional space, it is possible to detect a near-field light signal at each position on the surface of the subject.

  Furthermore, according to another embodiment of the near-field light detection method, an optical trap probe in which a metal member is provided on the whole or a part of the surface of the dielectric microstructure is used, and the optical trap probe is captured by the condensed light flux. Scan the position above and bring it close to the surface of the subject, and detect the scattered light generated by the scattered light beam scattered by both the optical trap probe and the surface of the subject, or part of the scattered light that has passed through the subject. To do.

  Further, according to another embodiment of the near-field light detection method, a light flux having a wavelength different from that of the collected light flux for capturing the optical trap probe is generated, and the light flux is incident on the optical trap probe. The reflected and scattered light beam is detected separately from the reflected light or scattered light of the condensed light beam for capturing the optical trap probe. Therefore, a stable S / N can be obtained in the near-field light detection signal.

  Furthermore, according to another embodiment of the near-field light detection method, a light flux having an intensity modulation frequency different from that of the collected light flux for capturing the optical trap probe is generated, the light flux is incident on the optical trap probe, and the optical trap The light beam reflected and scattered by the probe is detected separately from the reflected light or scattered light of the condensed light beam for capturing the optical trap probe. Therefore, a stable S / N can be obtained in the near-field light detection signal.

  In addition, by using a light beam whose vertical cross-sectional component is a ring shape as the condensed light beam for capturing the optical trap probe, stable capture of the optical trap probe and efficient generation of near-field light can be achieved. It becomes possible.

  Further, the focal position of the condensed light beam for capturing the optical trap probe is moved in a direction perpendicular to the optical axis of the condensed light beam, and the optical trap probe is scanned on the surface of the object, or the object By driving the optical trap probe relative to the subject by driving in a three-dimensional space, it is possible to detect a near-field optical signal at each position on the surface of the subject.

  The optical trap probe near-field optical microscope apparatus of the present invention generates near-field light while stably capturing an optical trap probe in which a metal member is provided on all or a part of the surface of a dielectric microstructure. It is possible to obtain a high S / N in the detected near-field light detection signal.

  In the optical trap probe near-field optical microscope apparatus of the present invention, an optical trap probe in which a metal member is provided on the entire surface or part of the surface of the dielectric microstructure is used. Scanning is performed close to the surface of the subject, and the scattered light generated by the scattered light beam being scattered by both the optical trap probe and the surface of the subject or a part of the scattered light passing through the subject is detected.

  FIG. 1 is a schematic cross-sectional view showing a configuration of an optical trap probe near-field optical microscope apparatus according to a first embodiment of the present invention. In the figure, the same reference numerals as those in the figure denote the same components. According to the optical trap probe near-field optical microscope apparatus of this embodiment, the light oscillated from the optical light source 1 for the optical trap is collimated by the lens 2 and selectively selects the light having the same wavelength as the light oscillated from the laser light source 1. The light is incident on the objective lens 4 which is folded back by the dichroic mirror 3 to be reflected and immersed in pure water 14. The light collected by the objective lens 4 captures the optical trap probe 15 dispersed in the medium. Here, when an example of the configuration of the optical trap probe 15 is shown in FIG. 2, metal particles 17 are fixed to a part of the surface of the dielectric sphere 16. As examples of materials and approximate dimensions, the dielectric sphere 16 is made of silica and has a diameter of several μm, and the metal particles 17 are made of gold and have a diameter of several tens of nanometers. The light incident on the dielectric sphere 16 is refracted on the surface of the dielectric sphere 16 and changes its direction. The change in the momentum of the light at that time becomes a trapping force. In order to capture the dielectric sphere 16 with the light condensed by the objective lens 4, the focal point is disposed slightly above the center position of the dielectric sphere 16. The laser light oscillated from the near-field light generating laser light source 6 is passed through the collimating lens 7, the beam splitter 8, and the objective lens 4 to the optical trap probe 15 captured by the light from the optical trap laser light source 1. Make it incident. The focal position is the lowest vertical position of the dielectric sphere 16. As a result, the metal particles 17 are affected by the gravitational force due to their own mass and the gradient force based on the electric field distribution at the condensing position of the laser light oscillated from the near-field light generating laser light source 6. It can be generally captured at the lowest vertical position. In this state, by the actuator 18 that can drive the objective lens 4 in the trap optical axis direction, the optical trap is placed at a position where the distance between the metal particle 17 of the optical trap probe 15 and the surface of the sample 9 of the subject is about several nm to 100 nm. The probe 15 is moved. Here, a necessary initial relative position between the objective lens 4 and the surface of the sample 9 is obtained in advance by measurement.

  In the state where the optical trap probe 15 is close to the surface of the sample 9, the near-field light is generated around the metal particles 17 by being illuminated by the light oscillated from the near-field light generating laser light source 6. Light scattered by interaction of near-field light with the surface of the sample 9 enters the detector 13 through the objective lens 4, the condenser lens 11, and the pinhole 12 for removing disturbance light. The near-field light information on the surface of the sample 9 can be obtained by the above procedure.

  As described above, in this embodiment, unlike the case of directly trapping nano-order metal fine particles as in the prior art, the trapped particles are dielectric particles having a size larger than the trap light wavelength, so that the position due to Brownian motion is Errors are unlikely to occur and can be trapped stably. In addition, by making the dielectric sphere 16 spherical, the metal particles 17 can be fixed at a position close to the surface of the sample 9, so that near-field light detection with high S / N becomes possible. Further, the metal particles 17 are made of a material having a negative dielectric constant with respect to the wavelength of the near-field light generating laser light source 6, thereby enhancing the electromagnetic field by surface plasmons at the interface between the dielectric sphere 16 and the metal particles 17. The effect can be obtained, the near-field light generated around the metal particles 17 can be increased, and the S / N can be improved. In general, the near-field light generating laser light source 6 is a light source having a wavelength in the visible region to the near infrared region. However, since gold and silver have a negative dielectric constant in the wavelength band, the metal particles 17 are used. Suitable as a material. Further, as shown in FIG. 1, by providing a trapping laser light source and a near-field light generating laser light source having different oscillation wavelengths, it is possible to independently set the light intensity of both. When using both trapping of optical trap probe and generation of near-field light with a single beam, the power required for trapping the probe is excessive compared to the optimum power for generating near-field light. Although there is a possibility that the S / N of the near-field light detection signal cannot be obtained, this problem can be avoided by preparing each of the trapping light beam and the measurement light beam.

  FIG. 3 is a schematic sectional view showing the configuration of the optical trap probe near-field optical microscope apparatus according to the second embodiment of the present invention. In the optical trap probe near-field optical microscope apparatus of the present embodiment shown in the figure, the objective lens 19 designed on the assumption that it is used in the atmosphere is used, and the optical trap probe can be operated in the atmosphere.

  Next, FIG. 4 is a schematic sectional view showing a configuration of an optical trap probe near-field optical microscope apparatus according to a third embodiment of the present invention. The optical trap probe near-field optical microscope apparatus of the present embodiment shown in the figure is an example provided with means for detecting the near-field light scattered by the optical trap probe 15 after passing through the test surface. According to the present embodiment, the near-field light generated around the metal particles 17 by the same near-field light generation procedure as in the first embodiment interacts with the surface of the sample 9 and is scattered. Here, when the sample 9 is a light-transmitting material, such as a dielectric or a metal thin film, a part of the scattered light passes through the sample 9 and enters the objective lens 4. This incident light is detected by a detector 13 through a condenser lens 11 and a pinhole 12 for removing disturbance light. With the above procedure, the near-field light including the surface and internal physical property information of the sample 9 can be detected.

  FIG. 5 is a schematic cross-sectional view showing a configuration of an optical trap probe near-field optical microscope apparatus according to a fourth embodiment of the present invention. The optical trap probe near-field optical microscope apparatus of this embodiment shown in the figure is an example of an apparatus in which the cross-sectional intensity distribution of the trap light beam is changed by inserting a filter in the optical path of the light beam for capturing the optical trap probe. is there. In this embodiment, by inserting a filter 20 having a low cross-sectional intensity distribution of the light beam oscillated from the laser light source 1 for optical trapping and collimated by the lens 2 only in the transmittance around the optical axis, It is possible to obtain a light beam having a “doughnut-like” hollow intensity distribution whose light intensity is lower than that of its surroundings. Here, in the cross-sectional intensity distribution of the trap light beam, when the light beam has a high light intensity around the optical axis, when the trap light beam is incident on the optical trap probe 15, the metal particles 17 constituting the light trap probe 15 are: There is a possibility of melting and deformation due to the influence of the energy of the trapped beam. However, by using a trap light beam having a hollow intensity distribution, the intensity of the component of the trap light beam irradiated to the metal particles can be reduced, so that the melting and deformation of the metal particles can be avoided by the energy of the trap light beam. In particular, as in the first embodiment, the metal particles 17 added to the dielectric structure of the optical trap probe 15 are sufficiently small, and the lowest point of the optical trap probe 15, that is, the collected light flux. When the metal particles are held in the vicinity of the optical axis, the strength of the trapped light beam applied to the metal particles 17 can be greatly reduced by using trap light having a hollow intensity distribution, so that the effect is great. Further, as a further effect of making the hollow intensity distribution, conventionally, light in the vicinity of the optical axis of the condensed light flux generates a force to press the optical trap probe 15 against the sample, but reduces its component. As a result, the effect of improving the trapping force of the optical trap probe 15 can also be obtained.

  In addition, although the example by filter insertion was given here as a shaping means of the cross-sectional intensity distribution, other methods may be used as long as the cross-sectional intensity distribution is a hollow distribution such as a beam shaping method using a diffraction effect by a hologram element. .

  FIG. 6 is a schematic cross-sectional view showing a configuration of an optical trap probe near-field optical microscope apparatus according to a fifth embodiment of the present invention. The optical trap probe near-field optical microscope apparatus of the present embodiment shown in the figure is high by using light sources having different intensity modulation frequencies for the trapped condensing light beam and the near-field light generating light beam of the optical trap probe 15. It is an example of the apparatus which can perform near-field light detection by S / N. First, the laser light source 1 for optical trap performs CW oscillation, the optical trap probe 15 is captured by the above-described method, and the optical trap probe 15 is brought close to the surface of the sample 9 by the actuator 18. The near-field light generating laser light source 6 generates a near-field light generating light beam based on an intensity modulation signal of, for example, several kHz received from the signal generator 21. A scattered component of the near-field light generated by this light beam is detected by the photodetector 13 via the objective lens 4 and the condenser lens 11. Here, the detected optical signal is also a signal having the same intensity modulation frequency as the signal generated by the previous signal generator 21. This signal and the signal generated by the signal generator 21 are input to the lock-in amplifier 22 as a reference signal and processed, so that the signal component detected by the photodetector 13 is synchronized with the reference signal from the signal generator 21. It becomes possible to extract the amplitude change of only the component as a DC signal. In addition to the dichroic mirror 3 that is slightly scattered by the trapped light flux for trapping and entering the photodetector 13, incident light from indoor light (not shown) and electromagnetic waves from peripheral devices are incident on the photodetector 13. Although there is a risk of being affected by environmental disturbance such as reception, this method can reduce the influence and improve the S / N of the detection light.

FIG. 7 is a schematic cross-sectional view showing a configuration of an optical trap probe near-field optical microscope apparatus according to a sixth embodiment of the present invention. The optical trap probe near-field optical microscope apparatus of the present embodiment shown in the same figure scans the focal position of the collected light flux for capturing of the optical trap probe 15 on a plane parallel to the sample surface, thereby providing an optical trap probe. 15 is an apparatus capable of two-dimensional scanning on the surface of the sample 9. As shown in the figure, in this embodiment, a galvanometer mirror 23 and a relay lens 24 are provided between the dichroic mirror 3 and the objective lens 4. By driving the two galvanometer mirrors 23 and changing the angle with respect to the incident light, the focal position of the collected light flux for capturing of the optical trap probe 15 and the light flux for generating near-field light is a plane perpendicular to the optical axis of the light flux. It can be moved to any position. The deflection angle of the galvanometer mirror 23 and the amount of movement of the focal position of the light beam are acquired in advance by experiments or calculations. Based on the correlation information between the mirror deflection angle and the amount of movement of the focal point of the light beam, which is obtained in advance by experiments as described above, the surface of the sample 9 is scanned on the surface of the sample 9 as shown in FIG. At the same time, the near-field light detection is performed as in the first embodiment, whereby the optical information of the entire surface of the sample 9 can be acquired. The amount of movement of the focal position of the light beam, that is, the size of the region in the scanning pattern 25 in FIG.
FIG. 9 is a schematic cross-sectional view showing a configuration of an optical trap probe near-field optical microscope apparatus according to a seventh embodiment of the present invention. The optical trap probe near-field optical microscope apparatus of the present embodiment shown in the same figure is mounted on a scanning stage 26 that can be driven in a direction parallel to the surface of the sample 9, so that the sample 9 is placed on the optical trap probe 15. This is a device capable of relatively two-dimensionally scanning the surface. In FIG. 9, the scanning stage 26 is an XY (biaxial) stage or a PZT tube scanner. The optical information of the entire surface of the sample 9 can be obtained by driving the scanning stage 26 on which the sample 9 is mounted with the scanning pattern 25 as shown in FIG. Note that the driving amount of the scanning stage 26, that is, the size of the region in the scanning pattern 25 of FIG. 8 is, for example, about ± 50 μm at the maximum. As another effect, when a mechanism capable of driving the scanning stage 26 in the optical axis direction of the collected light flux for capturing of the optical trap probe 15, such as a PZT tube scanner, is used, the actuator 18 in the fifth embodiment is used. Since it can be used as an alternative, the actuator 18 becomes unnecessary.

  In addition, this invention is not limited to the said Example, It cannot be overemphasized that various deformation | transformation and substitution are possible if it is description in a claim.

It is a schematic sectional drawing which shows the structure of the optical trap probe near-field optical microscope apparatus which concerns on 1st Example of this invention. It is a schematic sectional drawing which shows the example of a form of the probe of FIG. It is a schematic sectional drawing which shows the structure of the optical trap probe near-field optical microscope apparatus which concerns on the 2nd Example of this invention. It is a schematic sectional drawing which shows the structure of the optical trap probe near-field optical microscope apparatus which concerns on the 3rd Example of this invention. It is a schematic sectional drawing which shows the structure of the optical trap probe near-field optical microscope apparatus which concerns on the 4th Example of this invention. It is a schematic sectional drawing which shows the structure of the optical trap probe near-field optical microscope apparatus which concerns on the 5th Example of this invention. It is a schematic sectional drawing which shows the structure of the optical trap probe near-field optical microscope apparatus which concerns on the 6th Example of this invention. It is a top view which shows the drive pattern which drives a sample surface. It is a schematic sectional drawing which shows the structure of the optical trap probe near-field optical microscope apparatus which concerns on the 7th Example of this invention. It is a schematic sectional drawing which shows the structure of laser trap SNOM.

Explanation of symbols

1; laser light source for optical trap; 2; lens; 3; dichroic mirror;
4, 19; objective lens, 5; fine particle, 6; laser light source for generating near-field light,
7; collimating lens, 8; beam splitter, 9; sample,
10; scanning stage, 11; condenser lens, 12; pinhole,
13; Detector, 14; Pure water, 15; Optical trap probe, 16; Dielectric sphere,
17; metal particles, 18; actuator, 20; filter, 21; signal generator,
22; lock-in amplifier, 23; galvanometer mirror, 24; relay lens,
25; Scanning pattern, 26; Scanning stage.

Claims (14)

An optical trap probe in which a metal member is provided on the whole or a part of the surface of the dielectric microstructure;
A condensed light beam generating means for generating a condensed light beam of laser light to capture the optical trap probe;
An optical trap probe scanning means for bringing the optical trap probe close to the surface of the subject in a state where the optical trap probe is captured by the condensed light flux by the condensed light flux means;
Scattered light detection means for detecting scattered light generated by scattering of the condensed light beam by both the optical trap probe and the surface of the subject, or a part of the scattered light that has passed through the subject. An optical trap probe near-field optical microscope apparatus.   Generation means for generating a laser beam having a different oscillation wavelength from the condensed light beam by the condensed light beam means, light beam incident means for making the light beam incident on the optical trap probe, and reflection and scattering by the optical trap probe The optical trap probe near-field optical microscope apparatus according to claim 1, further comprising: a detecting unit that detects the light beam separately from the reflected light or scattered light of the condensed light beam for capturing the optical trap probe. .   The condensing light beam by the condensing light beam means is generated by means for generating a light beam of laser light having a different intensity modulation frequency, a light beam incident means for making the light beam incident on the optical trap probe, and reflected by the optical trap probe, 2. The optical trap probe near-field optical microscope according to claim 1, further comprising detection means for detecting the scattered light beam separately from the reflected light or scattered light of the condensed light beam for capturing the optical trap probe. apparatus.   The optical trap probe near-field light according to any one of claims 1 to 3, further comprising means for changing the condensed light beam by the condensed light beam means into a light beam whose cross-sectional light intensity distribution perpendicular to the optical axis is hollow. Microscope device.   The optical trap probe near-field optical microscope apparatus according to claim 1, wherein the dielectric microstructure is spherical.   The optical trap probe near-field optical microscope apparatus according to claim 1, wherein the metal member is either Au or Ag.   The optical trap probe proximity according to any one of claims 1 to 4, further comprising means for moving a focal position of the collected light beam for capturing the optical trap probe in a direction perpendicular to an optical axis of the collected light beam. Field light microscope device.   The optical trap probe near-field optical microscope apparatus according to claim 1, further comprising means for driving the subject in a three-dimensional space.   Using an optical trap probe in which a metal member is provided on the entire surface or a part of the surface of the dielectric microstructure, the optical trap probe is captured by a condensed light beam, and is then scanned close to the surface of the subject. A near-field light detection method, comprising: detecting scattered light generated by scattering of a light beam by both the optical trap probe and the surface of the subject, or part of the scattered light that has passed through the subject.   A light beam having a wavelength different from that of the condensed light beam for capturing the optical trap probe is generated, the light beam is incident on the optical trap probe, and the light beam reflected and scattered by the optical trap probe is passed through the optical trap probe. The near-field light detection method according to claim 9, wherein the detection is performed separately from reflected light or scattered light of the collected light beam for capturing.   A light flux having an intensity modulation frequency different from that of the condensed light flux for capturing the optical trap probe is generated, the light flux is incident on the optical trap probe, and the light flux reflected and scattered by the optical trap probe is converted into the optical trap. The near-field light detection method according to claim 9, wherein the detection is performed separately from the reflected light or scattered light of the collected light beam for capturing the probe.   The near-field light detection method according to claim 9, wherein a light beam having a ring-shaped vertical cross-sectional component is used as the condensed light beam for capturing the optical trap probe.   13. The focal position of the collected light beam for capturing the optical trap probe is moved in a direction perpendicular to the optical axis of the collected light beam, and the optical trap probe is scanned on the surface of the subject. The near-field light detection method according to any one of the above. The near-field light detection method according to claim 9, wherein the subject is driven in a three-dimensional space to scan the optical trap probe relative to the subject.

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