Abstract: A flexible shaft driven to rotate is inserted through a transparent sheath having pliability. By a fiber inserted through the inside thereof, low-coherence light is guided and is made to exit to a living-body tissue side which is an observation target through a lens and a prism forming an exit and entrance portion at the tip portion. Subsequently, the light reflected on the living-body tissue side is guided in order to produce an image. In that case, a positioning member for keeping the exit and entrance portion and the living-body tissue at a proper distance is formed at the tip portion of the sheath or the tip portion of an endoscope through which an optical probe is inserted and, therefore, a stable tomogram image can be produced.

Abstract: The present invention concerns a method and an apparatus for stabilizing the temperature of optical, in particular optically active, electrooptical, or acoustooptical components, preferably in scanning microscopy, in particular in confocal scanning microscopy, such that the temperature of the component can be held in stable fashion at a constant value in a space-saving manner, as simply as possible, and with as few additional assemblies as possible, and is characterized in that the energy that interacts with the component serves for stabilization.

Abstract: In a scanning probe microscope a probe associated with its sharp end includes a single conductive material.

Abstract: An apparatus and method for measuring optically the position or angle of a variety of objects or arrays of objects, including cantilevers in scanning probe microscopy, micromechanical biological and chemical sensors and the sample or a probe in surface profilometry. The invention involves the use of one or more diffractive optical elements, including diffraction gratings and holograms, combined with conventional optical elements, to form a plurality of light beams, each with a selectable shape and intensity, from a single light source, reflect the beams off mechanical objects and process the reflected beams, all to the end of measuring the position of such objects with a high degree of precision. The invention may also be used to effect mechanical changes in such objects.

Abstract: The invention concerns a method and an apparatus for automatically focusing an optical device onto a specific and predetermined region of a specimen. The apparatus compares signals corresponding to the vertical distance between a principal objective and a region of a specimen which is in focus to the vertical distance between the principal objective and a target region on the specimen. If the comparison of the distances indicates that they are not the same, the system automatically alters the distance between the specimen and the principal objective so that the target region is properly focused.

Abstract: An autofocus module for a microscope-based system includes at least two light sources, each of which generates a light beam for focusing. An optical directing device is provided that directs a respective portion of each light beam onto an incoupling means, which couples each of the light beams into the illuminating light beam of the microscope-based system and directs the light beams onto a specimen. A first and a second detector receive the light beams of the first and second light source reflected from the surface of the specimen, and ascertain the intensities on the first and second detector in time-multiplexed fashion.

Abstract: A pair of optical gratings are used to modulate light from an object, and the modulated light from either optical is used to determine the velocity of the object. Each optical grating is offset from a reference focal point by the same distance, one grating being offset in a positive direction, the other in a negative direction. Signals produced in response to the modulated light can be processed to determine a direction in which a primary collection lens should be moved in order to improve a focus of the imaging system on the object. The lens is moved incrementally in the direction so determined, and the process is repeated until an optimal focus is achieved. In a preferred embodiment, the signals are weighted, so that the optical grating disposed closest to the optimal focus position contributes the most to velocity detection.

Abstract: The autofocus module possesses, between the detector element (43) and the optical means, a cylindrical lens (42) that, for determination of the focus position, generates a line on the detector element (43). In addition, the detector element (43) is pivotable about an axis in such a way that it is inclined with respect to a plane defined by the surface of the specimen (20), and its inclination is adjustable. All the optical components of the autofocus module are combined in a housing (25) that can be quickly flange-mounted onto an existing microscope-based system (1).

Abstract: A light probe microscope has a probe having a tip, a mechanism for positioning the probe tip closely to a sample surface and causing two-dimensional scanning movement between the probe tip and the sample, a light source for emitting light to an area proximate the probe tip and the sample, a two-dimensional image sensor for receiving the light radiated from the sample and producing a two-dimensional image of the sample in accordance therewith, and a device for producing a light image based on a signal intensity of light in a detection region of the two-dimensional image.

Abstract: An optical arrangement for directing illumination light to a sample and for directing the detection light proceeding from the sample to a detector has a spectrally selective influencing means in the beam path of the detection light, which influences the polarization properties of the illumination light reflected or scattered from the sample in such a way that a polarizing beam splitter splits the illumination light reflected or scattered from the sample out of the detection light.

Abstract: A semiconductor wafer inspection system and method is provided which uses a multiple element arrangement, such as an offset fly lens array. The preferred embodiment uses a laser to transmit light energy toward a beam expander, which expands the light energy to create an illumination field. An offset fly lens array converts light energy from the illumination field into an offset pattern of illumination spots. A lensing arrangement, including a first lens, a transmitter/reflector, an objective, and a Mag tube imparts light energy onto the specimen and passes the light energy toward a pinhole mask. The pinhole mask is mechanically aligned with the offset fly lens array. Light energy passing through each pinhole in the pinhole mask is directed toward a relay lens, which guides light energy onto a sensor. The offset fly lens array corresponds to the pinhole mask.

Abstract: Techniques for utilizing a microscope inspection system capable of inspecting specimens at high throughput rates are described. The inspection system achieves the higher throughput rates by utilizing more than one detector array and a large field of view to scan the surface of the semiconductor wafers. The microscope inspection system also has high magnification capabilities, a high numerical aperture, and a large field of view. By using more than one detector array, more surface area of a wafer can be inspected during each scanning swath across the semiconductor wafers. The microscope inspection system is configured to have a larger field of view so that the multiple detector arrays can be properly utilized. Additionally, special arrangements of reflective and/or refractive surfaces are used in order to fit the detector arrays within the physical constraints of the inspection system.

Abstract: A scanning microscope for examination of a sample (31), having at least one optical component (89) that exhibits a wavelength-dependent characteristic and having an apparatus for wavelength-dependent detection that acquires measured values in at least two wavelength regions each characterized by a spectral width and a spectral position, is disclosed. The scanning microscope is characterized in that the wavelength-dependent characteristic of the at least one optical component (89) can be ascertained, can be at least temporarily stored in the form of a data set in a memory (49, 81), and can be considered upon acquisition and/or upon utilization of the measured values.

Abstract: The present invention discloses a method and an arrangement for scanning microscopic specimens (15) with a scanning device. The microscopic specimen (15) is displaceable on a specimen stage (35) in at least two spatial directions. A light beam (3) scans the specimen (15) within a defined scan field (52) by way of a scanning module (7), and the light (17) proceeding from the specimen is detected. A PC (34) is also provided for analysis and calculation. The scan field (52) is defined in such a way that it incompletely encompasses a specimen region that is to be examined. Means (23, 31) are provided which displace the specimen stage (35) in such a way that the entire specimen region of interest can be covered by the plurality of resulting scan fields (521, 522, . . . 52n). The data of the individual scan fields (521, 522, . . . 52n) detected from the specimen region being examined are assembled in the PC (34) into an overall image.

Abstract: A surface optical apparatus that includes a surface optical device with p-side and n-side electrodes, such as a surface emitting laser, a first substrate for supporting the surface optical device directly or through an elastic supporter formed of one or plural layers, and a first electrode wiring of at least a wire formed on the first substrate and electrically connected to one of the electrodes. A current is injected into or a voltage is applied across the surface optical device through the first electrode wiring and the p-side and n-side electrodes. A photodetector for detecting light from the surface optical device may also be arranged in the vicinity of the optical device.

Abstract: A confocal imaging system for imaging a surface. The system includes an area array sensor having rows of sensors for detecting light reflected from the surface, and an optical system arranged to focus light from different focal planes on the surface to different sensor rows of the area array sensor.

Abstract: Methods and apparatus are provided for computing focus information prior to scanning microscope slides with a line scan camera. The methods include a point-focus procedure that works by moving the slide to the desired measurement location, moving the objection lens through a predefined set of height values, acquiring imagery data at each height, and determining the height of maximum contrast. The methods also include a ribbon-focus procedure whereby imagery data are acquired continuously, while the slide and objective lens are in motion. Both methods may be applied with either a static or a dynamic implementation.

Abstract: The invention is directed to an arrangement for autofocusing onto a measuring location on an object moving in a direction which is at least approximately vertical to the optical axis of the imaging optics. According to the invention, a diaphragm device is to be provided the diaphragm opening of which extends in a direction aligned with the direction of movement of the measuring location; a receiving device for the measuring light has receiving areas arranged in a row beside each other and is inclined relative to the optical axis so that the image from the diaphragm device is incident on the receiving areas at an inclination of an angle &agr;; wherein the receiving device and the diaphragm opening are positioned relative to each other in such a way that characteristic measuring values are measured on the receiving areas when the measuring location is in or near the focus position.

Abstract: An autofocus module (30) for a microscope-based system (1) is equipped in such a way that a light source (31) which generates a measurement light bundle (32) is provided. A first axicon (34a) generates an eccentrically extending annularly divergent measurement light beam bundle (32a). A second axicon (34a) is provided in order to parallelize the remitted divergent measurement light beam bundle (32b). A differential diode (42) is mounted in the module (30) for determination of the focus position.

Abstract: A scanning unit for moving an object to be moved along at least one axis, which comprises a first actuator for moving the object along a first axis, the first actuator having a pair of end portions, and the object being attached to one of the end portions, the first actuator being held at a position in the vicinity of the center in dimension or the center of gravity thereof.

Abstract: The invention relates to an optical arrangement provided for a spectral fanning out of a light beam (1), preferably the detection beam path of a confocal microscope, especially for the subsequent splitting of the fanned out beam (2) out of the dispersion plane thereof. The optical arrangment is also provided for detecting the fanned out spectral regions (4), whereby the incoming light beam (1) is focused on a pinhole (7). The invention is characterized in that the pinhole (7) has a polygonal passageway (8) in order to realize a high dynamic response when the light beam is split into spectral regions (4) or into spectral colors.

Abstract: A flexible shaft driven to rotate is inserted through a transparent sheath having pliability. By a fiber inserted through the inside thereof, low-coherence light is guided and is made to exit to a living-body tissue side which is an observation target through a lens and a prism forming an exit and entrance portion at the tip portion. Subsequently, the light reflected on the living-body tissue side is guided in order to produce an image. In that case, a positioning member for keeping the exit and entrance portion and the living-body tissue at a proper distance is formed at the tip portion of the sheath or the tip portion of an endoscope through which an optical probe is inserted and, therefore, a stable tomogram image can be produced.

Abstract: According to the invention, in selecting an analyzed area of a scanning atom probe (SAP), there is adopted a method of using a tip of the lead-out electrode of SAP as a scanning probe of a scanning tunneling microscope (STM) and drawing a surface shape of a sample to thereby select the analyzed area and with regard to the tip of the lead-out electrode of SAP, there is formed an exclusive probe in a needle-like shape by a CVD micromaching technology or a lithographic method using focused ion beam in order to promote accuracy of the scanning probe of STM. Further, a conical dome of a conductive material is formed at the tip of the conical electrode mechanically formed by using a CVD fabricating method using focused ion beam and the tip is shaped by sputter etching to thereby form the lead-out electrode near to an ideal shape.

Abstract: An apparatus and method for measuring an aperture of a near-field optical probe is provided. The apparatus includes a light source, an optical detector, and a filter. The light source radiates light to the near-field optical probe. The optical detector is positioned before the near-field optical probe and receives the light transmitted through the near-field optical probe to detect light intensity. The filter is disposed between the light source and the optical detector and transmits only light of wavelengths in a specific mode from the light transmitted through the near-field optical probe. Thus, an aperture diameter of the near-field optical probe can accurately be measured in real-time without damaging the near-field optical probe.

Abstract: A method for providing a preliminary diagnosis of skin cancer, more specifically a screening risk assessment of pigmented lesions receiving digital photographs of skin abnormalities from a plurality of consumers at a server, receiving medical information related to each of the plurality of consumers at the server, assigning an identification to at least one of the consumers and the digital photographs, reviewing the digital photographs and categorizing the digital photographs into at least three categories so as to define category information, the at least three categories including a first category of a first risk, a second category of risk lower than the first category and a third category of insufficient photograph quality, and providing the category information as a function of the identification.

Abstract: A phase diversity wavefront correction system for use in a multiple aperture optical imaging system forms an in-focus image as a composite, focused image from the multiple apertures of the system and also forms an additional image which is deliberately made out of focus to a known extent. Taken together, the two images are processed to create one or more metrics, such as the power metric and sharpness metric. Neural networks are provided, each having an output corresponding to a parameter of an aperture of the imaging system, such as a piston position (axial displacement) or tip/tilt (angular displacement) of one telescope with respect to the others in the system.

Abstract: A system and method for indicating real time focus information for a scanning microscope. The system includes a detector, one or more bandpass filters, and one or more power indicators associated with the one or more bandpass filters. The detector detects an electrical signal from the scanning microscope. The bandpass filters filter the detected electrical signal. The bandpass filters are tuned to a desired range of frequencies. The power indicators detect and display average power of the electrical signal filtered by the corresponding bandpass filter. The system also includes a focusing device that generates a focusing signal based on the detected average power and focuses the scanning microscope based on the generated focusing signal. The focusing device automatically focuses the scanning microscope.

Abstract: The invention concerns a method for automatic focusing onto the surface of a sample P, in which sample P is illuminated by a measurement light beam 13 that strikes the sample surface at an incidence angle differing from 0°; light reflected therefrom is detected by means of a position-sensitive receiving surface (23); intensity values as allocated to positions on the receiving surface (23) are recorded and evaluated, and the opening of a field stop (7) is imaged onto the receiving surface (23), thereby generating an image that is smaller than the receiving surface (23).

Abstract: A scanning microscope having an acoustooptical component that splits out illuminating light for illumination of a sample from the output light of at least one light source, and conveys detected light proceeding from the sample to a detector, comprises, in the beam path of the output light from which the illuminating light is split out, at least one monitoring detector which is the measuring element of a control circuit. The scanning microscope is characterized in that fluctuations over time in the illuminating light power level are largely eliminated.

Abstract: The near-field spectrometer 10 comprises a Z-axis scanner 18, 20 for bringing a sample 24 and the tip of a probe 12 close to each other at a predetermined distance within a near-field 26 region when obtaining near-field spectral information and separating them from each other at a predetermined distance outside a near-field 26 region when obtaining back ground spectral information, and a data processor 22 for obtaining the true near-field spectral information free from the background by subtracting the background spectral information from the near-field spectral information, characterized in that a background information collector, during the separation of the sample 24 and the tip of the probe 12 at a predetermined distance outside the near-field 26 region, obtains the background spectral information for the corresponding portion to be measured.

Abstract: A method include scanning light from a light source which passes a confocal pattern on a sample through an objective lens while relatively moving one of the sample and the objective lens along a direction of an optical axis, acquiring two or more sectioning images by converting the light from the sample which penetrates the confocal pattern through the objective lens by a photoelectric converter, and changing an opening diameter of the variable diaphragm arranged at the pupil position of the objective lens or a conjugated position to the pupil position thereof to reduce a NA of the objective lens when focusing is not obtained and repeating an operation of taking two or more sectioning images by the photoelectric converter and obtaining the focusing position.

Abstract: A method and apparatus for extracting three-dimensional data of an object using an electron microscope are provided.

Abstract: The present invention discloses a light source (10) for the illumination of microscopic specimens. The invention also discloses a scanning microscope system that possesses a light source (10). The light source (10) emits a combined light beam that is emitted by a first laser (4) and a second laser (6). In the combined light beam, the light of the first laser (4) is synchronized with the light of the second laser (6).

Abstract: An autofocus module (30) for a microscope-based system (1) is equipped in such a way that a light source (31) which generates a measurement light bundle (32) is provided. A first axicon (34a) generates an eccentrically extending annularly divergent measurement light beam bundle (32a). A second axicon (34a) is provided in order to parallelize the remitted divergent measurement light beam bundle (32b). A differential diode (42) is mounted in the module (30) for determination of the focus position.

Abstract: The method of the present invention includes the steps of rotating a molecule having a predetermined structure by applying a first alternating current electromagnetic field to the molecule, wherein the first alternating current electromagnetic field is produced by an electromagnetic field generation means that is set to a predetermined phase, controlling a rotational phase of the molecule by applying a second electromagnetic field to the rotated molecule by an information recording means, detecting a signal using a signal detection means in accordance with a rotation of the molecule having the rotational phase which has been controlled, and outputting a shift between the phase of the first alternating current electromagnetic field and a phase of the detection signal from the signal detection means as information by an information reading means.

Abstract: The invention is based on an apparatus and a method for scanning specimens (1) using an optical imaging system (3) and a scanning stage (2), images of the specimen (1) being acquired by means of a camera (4), and/or measurements on the specimen (1) being made by means of an optical measurement device (5), at specimen points Xp, Yp. For that purpose, the scanning stage (2) is calibrated by obtaining and storing height values Z at different calibration positions X, Y of the scanning stage (2), and thereby generating a running height profile of the scanning stage (2). For the scanning of specimens (1), the specimen height positions Zp at specimen points Xp, Yp are determined by means of a reference height Zref of the specimen (1) together with the running height profile of the scanning stage (2).

Abstract: The invention is directed to an arrangement for autofocusing onto a measuring location (M) on an object (O) moving in a direction (R) which is at least approximately vertical to the optical axis (A) of the imaging optics (3). According to the invention, a diaphragm device is to be provided the diaphragm opening of which extends in a direction (R′) aligned with the direction of movement (R) of the measuring location (M); a receiving device for the measuring light has receiving areas (e1, e2, . . . en) arranged in a row beside each other and is inclined relative to the optical axis so that the image from the diaphragm device is incident on the receiving areas (e1, e2, . . . en) at an inclination of an angle a; wherein the receiving device and the diaphragm opening are positioned relative to each other in such a way that characteristic measuring values are measured on the receiving areas when the measuring location (M) is in or near the focus position.

Abstract: The autofocus module possesses, between the detector element (43) and the optical means, a cylindrical lens (42) that, for determination of the focus position, generates a line on the detector element (43). In addition, the detector element (43) is pivotable about an axis in such a way that it is inclined with respect to a plane defined by the surface of the specimen (20), and its inclination is adjustable. All the optical components of the autofocus module are combined in a housing (25) that can be quickly flange-mounted onto an existing microscope-based system (1).

Abstract: An electron beam apparatus includes a movable table which mounts a specimen, an electron optical system including an electron beam source which emits electron beams, an element for deflecting the emitted electron beams, an objective lens for converging and irradiating the deflected electron beams onto the specimen mounted on the table, and a detector for detecting a secondary electron emanated from the specimen by the irradiation of the electron beams. A surface height detection unit is provided which optically detects a height of a surface of the specimen by projecting light onto the surface of the specimen from an oblique direction to the surface and detecting light reflected from the specimen. A focus controller is provided for focusing the electron beam onto the surface of the specimen by controlling a position of the table in a height direction in accordance with the height information from the surface height detection unit.

Abstract: An optical waveguide probe is disclosed which is used for a scanning near-field optical microscope, has a low light propagation loss, and is capable of performing an AFM operation, and a manufacturing method thereof is disclosed. The vicinity of the tip of an optical waveguide 2 is bent toward a side of a probe portion 9 through a plurality of surfaces symmetrical with respect to a plane including an optical axis of the optical waveguide 2. By this, a loss of a propagated light 7 at a bent portion 10 is reduced, and the propagated light 7 can be condensed to a minute aperture 5, so that near-field light can be efficiently emitted from the minute aperture 5.

Abstract: Arrangement and method for focus monitoring in a microscope with digital image generation, preferably in a confocal microscope. The arrangement provides an additional, rotatably supported transparent optical component in the known construction of a microscope in front of a main beam splitter arranged in the beam path in the area of a parallel illumination beam path. According to the method, the images required for focus monitoring are recorded with a transparent optical component inclined by angle +&agr; or −&agr;. The images are checked for correlation of the image contents in the direction of beam displacement by pixel-by-pixel displacement. The determined displacement &Dgr;s at optimum correlation represents a measurement of the instantaneous focusing or defocusing. The suggested solution for focus monitoring is applicable with slight adaptations for all microscopes outfitted with digital image-generating methods and arrangements.

Abstract: A method and system for controlling resonance within a resonator-enhanced optical system provides improved tracking performance in resonator-enhanced optical measurement and data storage and retrieval systems. The system includes an illumination subsystem and a detection subsystem with an optical resonator interposed in an optical path between the illumination subsystem and the detection subsystem. The resonance of the optical resonator is tuned, either by changing the wavelength of the illumination subsystem or the geometric path length within the resonator. Closed-loop feedback control signals can thereby maintain resonance at a desired operating point. The feedback control signal components can be further used to provide measurement data if the resonance of the optical resonator is a function of a measured surface, such as when a reflective surface of the resonator is a surface under measurement.

Abstract: This invention provides an angled-dual-axis confocal scanning microscope comprising a fiber-coupled, angled-dual-axis confocal scanning head and a vertical scanning unit. The angled-dual-axis confocal scanning head is configured such that an illumination beam and an observation beam intersect optimally at an angle &thgr; within an object and the scanning is achieved by pivoting the illumination and observation beams using a single scanning element, thereby producing an arc-line scan. The vertical scanning unit causes the angled-dual-axis confocal scanning head to move towards or away from the object.

Abstract: Disclosed is an atomic force microscope. A Fabry-Perot interferometer where the intensity of light reflected at a cantilever through an optical fiber varies sensitively to a displacement of the cantilever is constructed to accurately measure a distance between the optical fiber and the cantilever. A Fabry-Perot resonator is formed by the optical fiber having an end of a concave mirror shape and a reflective surface of the cantilever. A displacement of a cantilever tip is measured by detecting a signal reflected at the resonator and a feedback signal corresponding to a variation in the displacement of the cantilever tip is generated. The displacement of the cantilever tip is kept constant by actuating a piezoelectric element in a Z-axis direction.

Abstract: This invention provides an angled-dual-axis optical coherence scanning microscope comprising a fiber-coupled, high-speed angled-dual-axis confocal scanning head and a vertical scanning unit. The angled-dual-axis confocal scanning head is configured such that an illumination beam and an observation beam intersect optimally at an angle &thgr; within an object and the scanning is achieved by pivoting the illumination and observation beams jointly using a high-speed scanning element. The vertical scanning unit causes the angled-dual-axis confocal scanning head to move towards or away from the object, thereby yielding a vertical cross-section scan of the object, while keeping the optical path lengths of the illumination and observation beams unchanged. By incorporating MEMS scanning mirrors and fiber-optic components, the angled-dual-axis optical coherence scanning microscope of the present invention can be miniaturized to provide a particularly powerful tool for in vivo medical imaging applications.

Abstract: A method of precision calibration of magnification of scanning microscopes with the use of a test diffraction grating includes positioning a test object on a stage of microscope so that strips of a test diffraction grating are perpendicular to a direction along which a calibration is performed, scanning of a selected portion of the test object along axes X and Y, measuring values of a signal S versus coordinates x and y in a plane of scanning and storing of the values S (x, y) in a digital form as a two-dimensional digital array, transforming the two-dimensional array of signals S(x, y) into a two-dimensional array S (u, v) by turning of the axes so that a direction of a new axis u is perpendicular to the strips of the grating and a direction of a new axis v coincides with the strips of the grating, line-by-line mathematical processing of the array S(u,v) for each line, converting of the one dimensional, complex function into a one-dimension spectrum of real values of a module, finding from the spectrum of th

Abstract: The present invention provides a method and apparatus for high-speed autofocus and tilt of an inspection surface in a microscope system. The method and apparatus herein described projects an array of spots, lines, circles, grids or other shapes on the surface to be adjusted. The superposition of the array on the surface is imaged by a CCD camera and captured for subsequent analysis. Analysis of the captured image determines both the distance and angle through which the surface must be adjusted to bring it into the focal plane of the optical system. Focus and tilt error is estimated by comparing image dilation and distortion with calibrated data.

Abstract: A scanning probe microscope uses two different scanners (also called “scanning stages”) that are completely detached each from the other, and are physically separated by a stationary frame. One scanner (called “x-y scanner”) scans a sample in a plane (also called “x-y plane”), while the other scanner (called “z scanner”) scans a probe tip (which is supported at a free end of a cantilever) in a direction (also called “z direction”) perpendicular to the plane. Detachment of the two scanners from one another eliminates crosstalk.

Abstract: The present invention relates to a device and to a method for examining and manipulating microscopic objects (1), with a microscope (2), a light source (3, 4) used to illuminate the object (1), an illumination beam path (5), a detector (6) used to detect the light returning from the object (1), a detection beam path (7), a light source (8) used for the object manipulation and a manipulation light beam path (9). The device according to the invention and the method according to the invention are intended to permit three-dimensional examination and manipulation of objects (1) whose dimension along the optical axis is greater than the depth of focus of the microscope objective used, with the additional intention that object manipulation should be possible at all sites of the three-dimensional object (1).

Abstract: A focusing system for a microscope has an objective lens, a sample stage, a reflected illumination system for generating fluorescence from a sample, a transmitted illumination system for irradiating light on the sample to capture a transmitted optical image, a set of optical elements for forming the transmitted optical image on the basis of a phase information included in light transmitted through the sample, an optical element for dividing the fluorescence image and the transmitted optical image, a sensor for capturing the transmitted optical image divided by the optical element for dividing light, a focus detecting section for detecting a focusing level of the transmitted optical image on the basis of a signal output from the sensor, and a driver for moving at least one of the objective lens and the stage to focus on the sample on the basis of the focusing level.