JP4937832B2 - 3D shape observation device - Google Patents

Description

  The present invention relates to a three-dimensional shape observation apparatus for observing a three-dimensional shape of a sample.

  In general, it is known to use, for example, a confocal laser scanning microscope or an interference microscope when observing a three-dimensional shape of a fine sample in a non-contact manner.

  For example, Patent Document 1 discloses a method for acquiring and observing a three-dimensional shape (image) of a sample using a confocal laser scanning microscope. In this confocal laser scanning microscope, the laser light emitted from the laser light source is condensed on the sample surface by the objective lens. Next, the confocal laser scanning microscope scans the sampled laser beam in a plane direction with respect to the sample, and receives the reflected laser beam reflected from the sample. At that time, the confocal laser scanning microscope receives the reflected laser light while changing the relative distance between the objective lens and the sample. Thereby, the confocal laser scanning microscope acquires a highly accurate observation image (all-focus image) having the surface information of the sample. Further, the confocal laser scanning microscope combines the relative distance information (sample height information) between the objective lens and the sample when the received light intensity of the reflected laser beam is maximized, and the above-described omnifocal image. Thereby, a three-dimensional shape image having the surface information and height information of the sample is acquired. The confocal laser scanning microscope observes the shape of the sample from this three-dimensional shape image.

  In general, a confocal laser scanning microscope uses a laser beam as light emitted from a laser light source to increase the light condensing property on the sample surface. In addition, the confocal laser scanning microscope has a pinhole at a position conjugate with the condensing position of the laser beam condensed by the objective lens, and the confocal laser scanning microscope has a reflected laser beam that has passed through the pinhole. Only receive light. As a result, the confocal laser scanning microscope has an advantage that a high-resolution three-dimensional shape image with little flare and high contrast can be acquired.

  However, since the resolution of the confocal laser scanning microscope depends on the NA of the objective lens, the resolution is generally lowered with a low-magnification objective lens having a small NA. Therefore, in order to obtain a more accurate three-dimensional shape image, it is generally necessary to use a high-magnification objective lens having a large NA. However, a high-magnification objective lens generally has a drawback that the observation field of the sample is narrowed.

  As described above, in a confocal laser scanning microscope, it is not easy to obtain a three-dimensional shape image of a sample having the surface information and height information of the sample over a wide range of areas with high resolution. Observing the area is not easy.

  For example, Patent Document 2 discloses a method for acquiring and observing a three-dimensional shape of a sample using an interference microscope. In the interference microscope, low-coherent illumination light whose coherence is suppressed is emitted, and is divided by, for example, a beam splitter or the like. One of the divided lights is condensed on the sample surface by the objective lens, and the other divided light is condensed on a reference mirror or the like. The reflected light reflected from the sample surface and the reflected light reflected from the reference mirror interfere with each other, and the interference microscope acquires an interference image from the interference light. The interference microscope acquires this interference image while changing the relative distance between the objective lens and the sample, and forms an observation image having highly accurate sample height information from the intensity distribution of the interference image. The interference microscope observes the shape of the sample from this image.

  In general, an interference microscope has an advantage that high-precision height information can be acquired even with a low-magnification objective lens having a small NA.

  However, the observation image acquired by the interference microscope is likely to be an image with poor contrast and flare. Further, since the interference fringes are superimposed on the luminance image of the sample, the state of the sample surface becomes difficult to understand. As the light source in the interference microscope, for example, a white light source that emits low-coherent white light is used. The condensing property of the white light emitted from the objective lens on the sample surface is not high compared to the condensing property of the laser light. Therefore, when comparing the surface information of the samples acquired by the interference microscope and the confocal laser scanning microscope, the interference microscope has a disadvantage that the resolution in the planar direction of the observation image is inferior. That is, the interference microscope cannot acquire surface information with high accuracy even if an omnifocal image is formed by dynamic focus processing.

  Therefore, when observing the three-dimensional shape of a sample in a wide range and with high accuracy, all of the surface information with high accuracy (high resolution and high contrast) is obtained with a wide observation field using a low magnification objective lens. It is necessary to use a confocal laser scanning microscope capable of acquiring a focus image and an interference microscope capable of acquiring high-precision height information. Therefore, a three-dimensional shape observation apparatus that can use both a confocal laser scanning microscope and an interference microscope is desired.

  FIG. 12 shows the configuration of a conventional three-dimensional shape observation apparatus that combines the configuration of a confocal laser scanning microscope and the configuration of an interference microscope.

  The three-dimensional shape observation apparatus 100 includes a stage 200 on which the sample 17 is placed, an interference objective lens 300 disposed above the sample 17, a microscope body 400 having the stage 200 and the interference objective lens 300, and a drive mechanism 40. The control main unit 51 and the control unit 500 having the memory 52 are configured.

  The microscope main body 400 includes a confocal laser scanning microscope optical system 400a in the confocal laser scanning microscope and an interference optical system 400b in the interference microscope above the interference objective lens 300. The confocal laser scanning microscope optical system 400a is an optical system different from the interference optical system 400b. The confocal laser scanning microscope optical system 400a and the interference optical system 400b irradiate the sample 17 with light. The confocal laser scanning microscope optical system 400a and the interference optical system 400b each have an observation optical system for observing light reflected from the sample 17. The observation optical system (second observation optical system) in the confocal laser scanning microscope optical system 400a is, for example, the laser light receiving element 11, and the observation optical system (first observation optical system) in the interference optical system 400b is For example, the imaging element 16. These observation optical systems also serve as, for example, an interference objective lens 300 that is a member shared by the confocal laser scanning microscope optical system 400a and the interference optical system 400b.

  The confocal laser scanning microscope optical system 400a in the confocal laser scanning microscope will be described. The confocal laser scanning microscope optical system 400a transmits a laser light source 1 that emits laser light 2 having linear polarization characteristics, a laser light 2 emitted from the laser light source 1, and a sample 17 described later. A two-dimensional scanning mechanism 4 that scans the surface of the sample 17 in a two-dimensional direction with respect to the surface of the sample 17 by rotating and the polarizing beam splitter 3 that reflects the laser light 2 reflected from the surface. Are arranged sequentially. The polarization beam splitter 3 transmits or reflects the laser beam 2 according to the polarization characteristics of the laser beam 2. The two-dimensional scanning mechanism 4 is, for example, a resonant scanner or a galvano scanner, and is arranged at a position conjugate with a pupil of an objective lens 31 described later.

  Further, the confocal laser scanning microscope optical system 400a includes a pupil projection lens 5, a first imaging lens 6, a quarter-wave plate on the optical path of the laser light 2 scanned by the two-dimensional scanning mechanism 4. 7 and the first beam splitter 8 are sequentially arranged. The quarter-wave plate 7 is scanned by the two-dimensional scanning mechanism 4 and converts the polarization direction of the laser light 2 transmitted through the pupil projection lens 5 and the first imaging lens 6 by a quarter wavelength. Thereby, the laser beam 2 emitted from the laser light source 1 is converted into circularly polarized light. The first beam splitter 8 is, for example, a dichroic prism or a dichroic mirror, and reflects the laser light 2 and transmits white light 13 (interference light) reflected from a sample 17 described later. The reflection transmittance characteristic of the first beam splitter 8 will be described later.

  On the reflected light path of the first beam splitter 8, a second beam splitter 14 disposed in an interference optical system 400b described later, an interference objective lens 300, and a stage 200 on which the sample 17 is placed are sequentially arranged. Has been placed. The second beam splitter 14 transmits the laser beam 2 reflected by the first beam splitter 8 and the laser beam 2 reflected from the sample 17, and divides (reflects or reflects) the white light 13 described later at a certain division ratio. Transmission). The reflection transmittance characteristic of the second beam splitter 14 will be described later. The objective lens 31 provided in the interference objective lens 300 focuses (condenses) the laser beam 2 on the surface of the sample 17. The interference objective lens 300 is provided with a first half mirror 32 below the objective lens 31, and the first half mirror 32 transmits the laser beam 2. The reflection / transmission characteristics of the first half mirror 32 will be described later. Thus, the confocal laser scanning microscope optical system 400 a irradiates the sample 17 with the laser light 2 emitted from the laser light source 1 by the objective lens 31.

  The laser beam 2 is reflected from the sample 17 and then returns to the polarization beam splitter 3 through the same optical path described above. At that time, the ¼ wavelength plate 7 converts the polarization direction of the laser light 2 reflected from the sample 17 by ¼ wavelength. Thereby, the laser beam 2 is converted again into linearly polarized light. The laser beam 2 converted into linearly polarized light has a characteristic of linearly polarized light orthogonal to the laser beam 2 emitted from the laser light source 1. Therefore, the polarization beam splitter 3 reflects the laser light 2.

  Further, the confocal laser scanning microscope optical system 400 a includes a second imaging lens 9, a pinhole 10, and a laser light receiving element 11 on the reflected light path of the laser light 2 reflected by the polarization beam splitter 3. They are arranged sequentially. The pinhole 10 is disposed at a position conjugate with the focal position of the objective lens 31, and is focused on the surface of the sample 17 by the objective lens 31, and only the laser light 2 that is focused on the surface of the sample 17. Pass through. The laser light receiving element 11 receives the laser light 2 that has passed through the pinhole 10 and outputs an output signal that changes in accordance with the light amount (intensity) of the received laser light 2 to the control main body 51. The control main body 51 forms luminance information (I) from the output signal. For the laser light receiving element 11, for example, a photomultiplier tube or a photodiode is used.

  As described above, the confocal laser scanning microscope optical system 400 a causes the laser light receiving element 11 to receive the laser light 2 (reflected light) reflected from the sample 17 and corresponds to the intensity of the received laser light 2. An output signal is output from the laser light receiving element 11.

  The distance in the optical axis direction between the interference objective lens 300 and the sample 17 (hereinafter referred to as a relative distance) is changed by a fixed pitch by the drive mechanism 40 and is stopped. The laser light receiving element 11 outputs an output signal at this relative distance to the control main body 51. The control main body 51 forms luminance information (I) at this relative distance from the output signal. Thus, the luminance information (I) is formed every time the relative distance changes. When a plurality of luminance information (I) formed for each relative distance is synthesized by the control main body 51, an omnifocal image having the surface information of the sample 17 with high resolution and high contrast with little flare is formed and observed. The

  As described above, the confocal laser scanning microscope optical system 400 a uses the interference objective lens 300 also as the interference optical system 400 b, is emitted from the laser light source 1, is irradiated onto the sample 17 by the objective lens 31, and is reflected from the sample 17. A second observation optical system for observing the surface information of the sample 17 from the laser beam 2 is provided.

  Next, the interference optical system 400b in the interference microscope will be described. The interference optical system 400b includes a white light source 12 that emits white light 13 that is low-coherent illumination light with reduced coherence, and a white light 13 that is emitted from the white light source 12 to the wavelength of the white light 13. The second beam splitters 14 that are divided at a constant division ratio according to the region are sequentially arranged. The white light source 12 is, for example, a halogen lamp or a mercury lamp that emits light in a wide region from the visible region to the infrared region. The second beam splitter 14 reflects a part of the divided white light 13 toward the interference objective lens 300.

  In the interference objective lens 300, the objective lens 31 forms an image (condensation / irradiation) of the white light 13 reflected by the second beam splitter 14 on the surface of the sample 17. At that time, the first half mirror 32 that is a light dividing member divides the white light 13 transmitted through the objective lens 31 at a constant division ratio according to the wavelength range of the white light 13. Specifically, the first half mirror 32 transmits one white light 13 toward the sample 17 and reflects the other white light 13 toward the reference plate (reference surface) 33. The reflection transmittance characteristics of the first half mirror 32 will be described later. As described above, the interference optical system 400 b irradiates the sample 17 and the reference plate 33 with the white light 13 emitted from the white light source 12.

  The reference plate 33 reflects the white light 13 reflected from the first half mirror 32 toward the first half mirror 32. The first half mirror 32 reflects the white light 13 reflected from the reference plate 33 toward the objective lens 31. The white light 13 that has passed through the first half mirror 32 is reflected by the sample 17. The first half mirror 32 transmits the white light 13 reflected from the sample 17 toward the objective lens 31. Thereby, the white light 13 reflected from the surface of the sample 17 interferes with the white light 13 reflected from the reference plate 33.

  The first beam splitter 8 transmits the interference light divided by the second beam splitter 14.

  Further, in the interference optical system 400b, a third imaging lens 15 that forms an image of the interference light transmitted through the first beam splitter 8 on the transmission optical path of the first beam splitter 8, and a third imaging. A first image sensor 16 that is disposed at the focal position of the lens 15 and captures an interference image of the sample 17 is sequentially disposed. The interference image is the white light 13 reflected from the surface of the sample 17 that interferes and the white light 13 reflected from the reference plate 33. For example, a CCD camera or a CMOS sensor is used for the first image sensor 16. In the interference image picked up by the first image sensor 16, interference fringes (interference image information) overlap the surface image of the sample 17. The first image sensor 16 outputs the interference image information to the control main body 51 as an output signal (second output signal).

  As described above, the interference optical system 400b includes the first observation optical system that forms an image of the light reflected from the interfering sample 17 and the light reflected from the reference plate 33 to observe the interference image.

  As described above, the relative distance is changed by a fixed pitch by the drive mechanism 40, and is stopped. An interference image is formed each time the relative distance changes. The interference image formed for each relative distance is acquired by the control main body 51, and a change in luminance due to interference is calculated by the control main body 51 from the plurality of acquired interference images. Thereby, the height information (height image) of the surface of the sample 17 is formed by the control main body 51. As described above, a high resolution height can be obtained even with a low-magnification objective lens having a small NA.

  Next, the configuration of the interference objective lens 300 will be described. As described above, the interference objective lens 300 transmits the laser light 2, the objective lens 31 that irradiates the surface of the sample 17 with the white light 13, and the laser light 2, and splits the white light 13 (one of the white light 13). Is transmitted toward the sample 17 and the other of the white light 13 is reflected), and a reference plate 33 irradiated with the white light 13 reflected from the first half mirror 32 is provided. Yes. The first half mirror 32 is disposed between the objective lens 31 and the sample 17. The reference plate 33 is disposed at a position optically conjugate with the object-side focal position of the interference objective lens 300 via the first half mirror 32 (on the optical path divided by the first half mirror 32). Since the surface of the reference plate 33 (the surface facing the first half mirror 32) is a mirror surface, the irradiated white light 13 is reflected to the first half mirror 32. The first half mirror 32 reflects this white light 13 to the objective lens 31. The reference plate 33 is disposed on the optical path divided by the first half mirror 32. Thus, the objective lens 31, the first half mirror 32, and the reference plate 33 are disposed on the optical axis of the interference objective lens 300, and constitute a Mirau-type interference objective lens.

  Since the interference objective lens 300 (objective lens 31) is a member that is shared (shared) by the confocal laser scanning microscope and the interference microscope, the observation visual field in the confocal laser scanning microscope and the observation visual field in the interference microscope are the same. It is a thing.

  In FIG. 12, the Mirau interference objective lens is shown as an example. However, as shown in FIG. 13, the basic configuration, operation, and action are the same in the Michelson interference objective lens.

  As shown in FIG. 13, a Michelson interference objective lens 300 includes an objective lens 31, an objective beam splitter 34 that transmits one of the laser light 2 and the white light 13, and reflects the other of the white light 13, and an objective. And a reference mirror (reference surface) 35 that is irradiated with the white light 13 reflected by the beam splitter 34. The objective lens 31 and the objective beam splitter 34 are disposed on the optical axis of the interference objective lens 300. The reference mirror 35 is disposed on the reflected light path of the objective beam splitter 34, and is disposed at a position optically conjugate with the object side focal position of the objective lens 31 via the objective beam splitter 34. Since the surface of the reference mirror 35 (the surface facing the objective beam splitter 34) is a mirror surface, the irradiated white light 13 is reflected to the objective beam splitter 34. The objective beam splitter 34 reflects the white light 13 to the objective lens 31. The reflection transmittance characteristic of the objective beam splitter 34 will be described later. Thus, the objective lens 31, the objective beam splitter 34, and the reference mirror 35 constitute a Michelson type interference objective lens.

  Next, the reflection transmittance characteristic of the first beam splitter 8 will be described with reference to FIG. The reflection transmittance characteristic is a relationship between the reflectance and transmittance of the first beam splitter 8 and the wavelength range of light (laser light 2 and white light 13) reflected or transmitted through the first beam splitter 8. is there. Further, the reflection transmittance characteristics of the second beam splitter 14, the first half mirror 32, and the objective beam splitter 34 will be described with reference to FIG. The reflection transmittance characteristics include the second beam splitter 14, the first half mirror 32, the reflectance and transmittance of the objective beam splitter 34, the second beam splitter 14, and the first half mirror. 32 and the wavelength range of light (laser light 2 and white light 13) reflected or transmitted through the objective beam splitter 34.

  As shown in FIGS. 14 and 15, the first beam splitter 8, the second beam splitter 14, the first half mirror 32, and the objective beam splitter 34 have reflectivities according to the wavelength range of light. And the transmittance is different. As described above, the first beam splitter 8 reflects or transmits light according to a desired wavelength range of light. The second beam splitter 14, the first half mirror 32, and the objective beam splitter 34 divide the light at a desired ratio according to the desired wavelength range of the light. The divided light is transmitted or reflected. That is, the first beam splitter 8 has a spectral characteristic that reflects the laser light 2 by approximately 100% and transmits the white light 13 by approximately 100%. The second beam splitter 14, the first half mirror 32, and the objective beam splitter 34 transmit the laser light 2 approximately 100%, reflect the white light 13 approximately 50%, and transmit approximately 50%. Has spectral characteristics.

  The control main body 51 described above is connected to the interference objective lens 300 via the drive mechanism 40. The drive mechanism 40 moves the interference objective lens 300 in the focal direction (Z direction, optical axis direction), for example, and performs positioning to be positioned on the surface of the sample 17. As described above, the drive mechanism 40 moves at least one of the interference objective lens 300 or the stage 200 along the optical axis 18 to change the relative distance between the interference objective lens 300 and the sample 17 in the optical axis direction.

Next, the operation of the three-dimensional shape observation apparatus 100 when setting an acquisition range for acquiring height information will be described.
This acquisition range is a range from the upper limit position to the lower limit position in the relative distance in the optical axis direction between the sample 17 and the interference objective lens 300 for acquiring height information.

  The control main body 51 acquires an observation image from the confocal laser scanning microscope optical system 400a, and focuses on the surface of the sample 17 based on the observation image. Next, the control main body 51 uses the drive mechanism 40 based on the observation image acquired from the confocal laser scanning microscope optical system 400a to obtain the acquisition range of the confocal laser scanning microscope optical system 400a (the upper limit position and the relative distance). Set the lower limit position. Next, the control main body 51 causes the memory 52 to store the set acquisition range of the confocal laser scanning microscope optical system 400a.

  In addition, the control main body 51 acquires an observation image from the interference optical system 400b, and roughly focuses on the surface of the sample 17 based on the observation image. Next, the control main body 51 finely focuses so that an interference fringe is generated in the observation image. Next, the control main body 51 sets the acquisition range of the interference optical system 400b by the drive mechanism 40 based on the observation image acquired from the interference optical system 400b. Next, the control main body 51 stores the set acquisition range of the interference optical system 400 b in the memory 52.

  As described above, the reason why the acquisition ranges are set for the confocal laser scanning microscope optical system 400a and the interference optical system 400b is that the optical characteristics of the confocal laser scanning microscope and the interference microscope are different from each other. This is because they do not match.

As described above, the control main body 51 moves the interference objective lens 300 along the optical axis 18 by the drive mechanism 40 at the relative distance (between the upper limit position and the lower limit position) after setting, and interferes with the luminance information (I). Get a statue. Thereby, the three-dimensional shape observation apparatus 100 acquires a three-dimensional shape image of the sample 17 and observes it with reference to the three-dimensional shape image.
Japanese Patent Laid-Open No. 09-068413 JP 2004-028647 A

  However, since the above-described three-dimensional shape observation apparatus 100 sets acquisition ranges for the confocal laser scanning microscope optical system 400a and the interference optical system 400b, the operability is poor, and the three-dimensional shape image of the sample 17 is displayed. It takes time to get it.

  Therefore, in view of the above circumstances, the present invention can set the acquisition range of the height information of the sample in the optical system other than the interference optical system and the interference optical system by the observation optical system in the optical system other than the interference optical system. It is an object to provide a three-dimensional shape observation apparatus that can easily acquire a three-dimensional shape image in a short time.

In order to achieve the object, the present invention provides a light source that emits light, an objective lens that irradiates a sample with the light emitted from the light source, and is disposed between the objective lens and the sample. A light splitting member that transmits one of the lights by splitting the light transmitted through the light and reflects the other light, and an optical path split by the light splitting member, and is reflected from the light splitting member An interference objective lens having a reference surface irradiated by the other light, and forming an image of the light reflected from the sample that interferes with the light reflected from the reference surface and observing an interference image. A second view of observing surface information of the sample from the light reflected from the sample, wherein the interference optical system is also used as the interference optical system. An optical system different from the interference optical system, a moving mechanism that adjusts a relative distance between the interference objective lens and the sample in the optical axis direction, and the moving mechanism adjusts the relative distance. In this case, a first acquisition range for acquiring the height information of the sample in the optical system is calculated based on the surface information observed by the second observation optical system, and the calculated first A control unit that calculates a second acquisition range for acquiring height information of the sample in the interference optical system from the acquisition range of the interference optical system , and the first acquisition range depending on a coherence distance of the interference optical system A storage unit that stores an addition range to be added to the control unit, wherein the control unit calculates the second acquisition range from the first acquisition range and the addition range. 3D shape observation device To provide.

In order to achieve the object, the present invention provides a light source that emits light, a first objective lens that irradiates a sample with the light emitted from the light source when arranged on the optical axis, and A light splitting member disposed between the first objective lens and the sample and splitting the light transmitted through the first objective lens to transmit one of the lights and reflect the other light; An interference objective lens that is disposed on the optical path divided by the light splitting member and is irradiated with the other light reflected from the light splitting member, and the interference objective lens that is reflected from the interfering sample An interference optical system having a first observation optical system that forms an image of light and the light reflected from the reference surface to observe an interference image, and the interference objective lens having the first objective lens Different second objective lens And an optical system different from the interference optical system, and the interference objective lens disposed on the optical axis, or the second observation optical system. A moving mechanism that adjusts a relative distance between the objective lens and the sample in the optical axis direction, and the second objective lens is disposed on the optical axis, and the moving mechanism adjusts the relative distance when the relative distance is adjusted. Based on the surface information observed by the second observation optical system, a first acquisition range for acquiring the height information of the sample in the optical system is calculated, and from the calculated first acquisition range A control unit that calculates a second acquisition range for acquiring the height information of the sample in the interference optical system, and an addition to the first acquisition range depending on a coherence distance of the interference optical system Addition range to be Comprising a storage unit for憶, wherein the control unit provides a three-dimensional shape observation apparatus and calculates the second acquisition range from the addition range as the first acquisition range.
In order to achieve the object, the present invention provides a light source that emits light, an objective lens that irradiates the sample with the light emitted from the light source, and is disposed between the objective lens and the sample. A light splitting member that splits the light transmitted through the lens and transmits one of the lights and reflects the other light, and is disposed on an optical path split by the light splitting member, and is reflected from the light splitting member An interference objective lens having a reference surface illuminated by the other light, and forming an image of the light reflected from the interfering sample and the light reflected from the reference surface to observe an interference image The interference optical system comprising: an interference optical system having a first observation optical system; and a second observation optical system that uses the interference objective lens as the interference optical system and observes surface information of the sample. An optical system different from the above, a moving mechanism that adjusts the relative distance between the interference objective lens and the sample in the optical axis direction, and the moving mechanism adjusts the relative distance by the second observation optical system. A first acquisition range for acquiring height information of the sample in the optical system is calculated based on the observed surface information, and the sample in the interference optical system is calculated from the calculated first acquisition range. A control unit that calculates a second acquisition range for acquiring the height information of the object, a subtraction range that is subtracted from the first acquisition range depending on the optical characteristics of the objective lens, and the interference optics A storage unit that stores an addition range that is added to the first acquisition range depending on a coherence distance of the system, and the control unit includes the first acquisition range and the subtraction range. And the addition range Providing a three-dimensional shape observation apparatus and calculates the second acquisition range.
In order to achieve the object, the present invention provides a light source that emits light, a first objective lens that irradiates a sample with the light emitted from the light source when arranged on the optical axis, and A light splitting member disposed between the first objective lens and the sample and splitting the light transmitted through the first objective lens to transmit one of the lights and reflect the other light; An interference objective lens that is disposed on the optical path divided by the light splitting member and is irradiated with the other light reflected from the light splitting member, and the interference objective lens that is reflected from the interfering sample An interference optical system having a first observation optical system that forms an image of light and the light reflected from the reference surface to observe an interference image, and the interference objective lens having the first objective lens Different second objective lens An optical system different from the interference optical system, and the interference objective lens arranged on the optical axis or the second observation optical system for observing surface information of the sample A moving mechanism that adjusts the relative distance between the objective lens and the sample in the optical axis direction, and the second objective lens are arranged on the optical axis, and the moving mechanism adjusts the relative distance when the relative distance is adjusted. Calculating a first acquisition range for acquiring height information of the sample in the optical system based on the surface information observed by the two observation optical systems, and calculating the first acquisition range from the calculated first acquisition range A control unit that calculates a second acquisition range for acquiring the height information of the sample in the interference optical system, and subtracts from the first acquisition range depending on the optical characteristics of the second objective lens Subtraction range A storage unit that stores an addition range that is added to the first acquisition range depending on a coherence distance of the interference optical system, and the control unit includes the first acquisition range, A three-dimensional shape observation apparatus is provided that calculates the second acquisition range from the subtraction range and the addition range.

  According to the present invention, the observation optical system in the optical system other than the interference optical system can set the acquisition range of the sample height information in the optical system other than the interference optical system and the interference optical system. A three-dimensional shape observation apparatus that can be easily acquired in a short time can be provided.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.
FIG. 1 is a configuration diagram of a three-dimensional shape observation apparatus according to the first embodiment. FIG. 2 is a schematic view of a revolver that holds a plurality of interference objective lenses. FIG. 3 is a diagram showing the reflection transmittance characteristics of the third beam splitter 36. FIG. 4 is a diagram showing the transmittance characteristics of the bandpass filter 20. FIG. 5 is a diagram showing the transmittance characteristics of the bandpass filter 21. FIG. 6 shows changes in interference intensity in the optical axis direction in the interference optical system corresponding to the surfaces 17a and 17b. The same members as those in the three-dimensional shape observation apparatus shown in FIG. In the following description, the relative distance indicates a distance between the interference objective lens 300 and the sample 17 in the optical axis direction.

  The three-dimensional shape observation apparatus 100 in this embodiment includes a stage 200, an interference objective lens 300, a microscope main body 400, a control unit 500, a display unit 600 that displays a three-dimensional shape image of the sample 17, and a three-dimensional shape. The driving unit 40 includes an instruction unit 700 that outputs an instruction to cause the observation apparatus 100 to observe the three-dimensional shape of the sample 17.

  The drive mechanism 40 adjusts the relative distance by moving at least one of the interference objective lens 300 or the stage 200 along the optical axis direction. In the present embodiment, the relative distance may be manually adjusted, and the adjustment of the relative distance is not particularly limited.

  In the present embodiment, as shown in FIG. 2, a plurality of interference objective lenses 300 having different optical characteristics (for example, NA and magnification) may be held by a revolver 45 that is an objective lens placement unit. In this case, in the present embodiment, the NA of one interference objective lens 300a (hereinafter referred to as an interference objective lens 300a having a low NA) is the NA of the other interference objective lens 300b (hereinafter, an interference objective lens 300b having a high NA). Lower). The interference objective lens 300a (first objective lens) having a low NA and the interference objective lens 300b (second objective lens) having a high NA have different optical characteristics (observation field). The revolver 45 holds the interference objective lens 300a having a low NA and the interference objective lens 300b having a high NA, and any one of them is arranged on the optical axis. Thereby, this embodiment can adjust the breadth of an observation visual field, and can adjust the time which takes in the surface optical image information and interference image information which are mentioned later. The optical characteristics do not need to be limited to NA or the like as long as the observation visual field can be adjusted. In this case, the drive mechanism 40 moves the revolver 45 along the optical axis 18, and the interference objective lens 300 having a low NA and the interference objective lens 300 having a high NA are arranged on the optical axis. The relative distance with the sample 17 is changed. Of course, the stage 200 may be moved along the optical axis 18.

  A third beam splitter 36 is arranged in the interference objective lens 300 in the present embodiment. As shown in FIG. 3, the third beam splitter 36 has different reflectivities and transmissivities depending on the wavelength range of the transmitted light. Specifically, the third beam splitter 36 transmits approximately 100% of light having a wavelength of approximately 780 nm or less (hereinafter referred to as visible light) toward the sample 17, and light having a wavelength of approximately 780 nm or more (hereinafter, infrared). About 50% of the light (referred to as light) is transmitted toward the sample 17, and about 50% of the infrared light is reflected toward the reference plate 33.

  In the microscope main body 400 in the present embodiment, the second half mirror 23 having the same function as the second beam splitter 14 is disposed.

  On the optical axis between the second half mirror 23 and the third imaging lens 15, at least one of the band pass filter 20 and the band pass filter 21 is disposed.

  The transmittance characteristics of the band-pass filter 20 have different transmittances depending on the wavelength range of transmitted light as shown in FIG. The bandpass filter 20 transmits light (infrared light) in a wavelength region centered on a desired wavelength of approximately 900 nm.

  The transmittance characteristics of the band-pass filter 21 have different transmittances depending on the wavelength range of transmitted light as shown in FIG. The band pass filter 21 transmits light (visible light) in a wavelength region centered on a desired wavelength of approximately 550 nm.

  Thus, the band-pass filter 20 and the band-pass filter 21 have different transmittances depending on the desired wavelength. The bandpass filter 20 and the bandpass filter 21 are held by the filter switching mechanism 19. The filter switching mechanism 19 is rotated at a desired rotational speed around the central axis 22a by the first driving unit 22 which is, for example, a motor. The first drive unit 22 is controlled by the control main body 51. When the control main body 51 drives the first drive unit 22, the filter switching mechanism 19 rotates. Thereby, at least one of the bandpass filter 20 and the bandpass filter 21 is arranged on the optical axis.

  When the band-pass filter 20 is disposed on the optical axis, the first image sensor 16 in the present embodiment captures an interference image by infrared light and outputs an output signal corresponding to the captured infrared light to the control main body unit. To 51. In addition, when the band-pass filter 21 is disposed on the optical axis, the first image sensor 16 captures an optical microscope observation image using visible light, and outputs an output signal corresponding to the captured visible light to the control main body 51. Output. The optical microscope observation image indicates surface information of the sample surface.

  As described above, in the three-dimensional shape observation apparatus 100 according to the present embodiment, an optical microscope optical system is formed by arranging the bandpass filter 21 on the optical axis, and the bandpass filter 20 is arranged on the optical axis. Thus, an interference optical system is formed. Thus, the three-dimensional shape observation apparatus 100 has both an optical microscope optical system and an interference optical system. The optical microscope optical system is an optical system other than the interference optical system. Each of the optical microscope optical system and the interference optical system has an observation optical system, and the observation optical system is a member that is shared (shared) by the optical microscope optical system and the interference optical system, for example, of the interference objective lens 300. An objective lens 31 is provided.

  The control unit 500 includes a control main body (for example, CPU) 51, a memory 52 connected to the control main body 51, and an image processing unit 53.

  The control main body 51 switches a revolver for switching the illumination intensity of the white light source 12, the sensitivity adjustment of the first image sensor 16, the shutter speed of the first image sensor 16, and the interference objective lens 300 arranged on the optical axis. The operation of rotating 45 and the drive operation of the first drive unit 22 are controlled.

  In addition, the control main body 51 acquires an output signal output from the first image sensor 16 when the bandpass filter 21 is disposed on the optical axis. Further, the control main body 51 acquires an output signal output from the first image sensor 16 when the bandpass filter 20 is disposed on the optical axis, and the interference imaged by the first image sensor 16 is obtained. Image information is calculated. Further, the control main body 51 forms the height information of the sample 17 from the interference image information by an operation described later. This height information represents the height of the sample 17.

  The memory 52 stores a corresponding output signal (optical microscope observation image) obtained by the visible light acquired by the control main body 51 and interference image information and height information formed by the control main body 51. Further, the memory 52 is configured such that, for example, the interference objective lens 300 emits light when setting parameters used when the image processing unit 53 forms a three-dimensional shape image of the sample 17 or when the drive mechanism 40 adjusts the relative distance. A movement amount (a constant pitch) for moving along the axis 18 is stored. The setting parameters are, for example, an optimum pitch for the control main body 51 to acquire an output signal and a moving speed of the interference objective lens 300. When the 3D shape observation apparatus 100 acquires a 3D shape image, the setting parameters are output to the control main body 51. Further, the memory 52 stores an upper limit position, a lower limit position, an acquisition range D1, an acquisition range D2, an addition range ARL, an addition range ARH, and a focus correction table which will be described later.

  The pitch is set in advance according to the optical characteristics (for example, NA) of the interference objective lens 300 disposed on the optical axis. Therefore, the memory 52 stores a combination of the optical characteristics of the interference objective lens 300 and a pitch corresponding to the optical characteristics. For example, when the interference objective lens 300b having a high NA is arranged on the optical axis instead of the interference objective lens 300a having a low NA as described above, the pitch also changes. The control main body 51 moves the interference objective lens 300 arranged on the optical axis by the pitch input to the drive mechanism 40 along the optical axis 18 to adjust the relative distance.

  The image processing unit 53 forms an optical microscope observation image (surface information), which will be described later, from an output signal stored in the memory 52, and a height image (three-dimensional shape image) from the height information stored in the memory 52. Form.

  The display unit 600 displays at least one of the optical microscope observation image (surface information) and the height image (three-dimensional shape image) formed by the image processing unit 53, and uses the three-dimensional shape observation apparatus 100. The user has a control screen for instructing the 3D shape observation apparatus 100 to operate. The display unit 600 is, for example, a liquid crystal display or a CRT display.

  The instruction unit 700 is, for example, a mouse, a keyboard, a touch panel, or the like. In addition, the instruction unit 700 instructs the control main body unit 51 to set an acquisition range for acquiring height information. This acquisition range is a range from the upper limit position to the lower limit position in the relative distance between the sample 17 and the objective lens 31 in the optical axis direction when acquiring height information.

  The control unit 500, the display unit 600, and the instruction unit 700 are a dedicated controller unit, a PC, and the like that observe the three-dimensional shape of the sample 17.

Next, an operation method of the three-dimensional shape observation apparatus 100 in the present embodiment will be described.
The white light 13 emitted from the white light source 12 is divided by the second half mirror 23 at a constant division ratio as shown in FIG. The white light 13 reflected downward (on the interference objective lens 300 side) by the division is transmitted through the objective lens 31. The transmitted white light 13 is divided by the third beam splitter 36. One white light 13 transmitted through the third beam splitter 36 by the division irradiates the sample 17. Further, the other white light 13 reflected by the division irradiates the surface of the reference plate 33. Since the surface of the reference plate 33 is a mirror surface, the white light 13 is reflected by the reference plate 33.

  The sample 17 is irradiated with a light amount of approximately 100% of visible light and a light amount of approximately 50% of infrared light due to the reflection transmittance characteristic of the third beam splitter 36. The reference plate 33 is irradiated with a light amount of approximately 50% of the infrared light due to the reflection transmittance characteristic of the third beam splitter 36. The reference plate 33 is not irradiated with visible light due to the reflection transmittance characteristic of the third beam splitter 36. The reference plate 33 reflects the infrared light reflected by the third beam splitter 36.

  The white light 13 reflected from the sample 17 is transmitted again through the third beam splitter 36 and the objective lens 31 based on the reflection transmittance characteristic of the third beam splitter 36 described above. The white light 13 reflected from the reference plate 33 is reflected again by the third beam splitter 36 based on the reflection transmittance characteristic of the third beam splitter 36 described above, and passes through the objective lens 31. At this time, the reflected light reflected from the reference plate 33 is only infrared light. Therefore, the reflected light reflected from the sample 17 causes light interference only in this wavelength region. For this reason, the transmitted light that passes through the objective lens 31 includes light in a wavelength region having such interference information (infrared light) and light in a wavelength region having no interference information (visible light).

  The white light (interference light) 13 that has passed through the objective lens 31 passes through the second half mirror 23 and the band-pass filter 20 or the band-pass filter 21 arranged on the optical axis. The transmitted light that has passed through the bandpass filter 20 or the bandpass filter 21 is imaged by the third imaging lens 15 and imaged by the first imaging element 16.

  When the band-pass filter 20 is arranged on the optical axis by the filter switching mechanism 19, the first image sensor 16 has a wavelength of about 900 nm as the center due to the transmittance characteristic of the band-pass filter 20 shown in FIG. An interference image by infrared light is captured.

  Further, when the band-pass filter 21 is arranged on the optical axis by the filter switching mechanism 19, the first imaging element 16 is centered on a wavelength of about 550 nm due to the transmittance characteristics of the band-pass filter 21 shown in FIG. The optical microscope observation image by visible light is imaged.

  Thus, when the filter switching mechanism 19 switches the band pass filter arranged on the optical axis, the first image sensor 16 captures infrared light (interference image) or visible light (optical microscope observation image).

  The first imaging element 16 outputs an output signal to the control main body 51 when imaging infrared light or visible light. The control main body 51 forms an optical microscope observation image (surface information) and height information from the acquired output signal. The formed optical microscope observation image (surface information) and height information are stored in the memory 52. The image processing unit 53 forms an observation image (optical microscope observation image) from the optical microscope observation image stored in the memory 52, and the height image (three-dimensional shape image) from the height information stored in the memory 52. Form. The display unit 600 displays at least one of an optical microscope observation image (surface information) and a height image (three-dimensional shape image).

Next, an operation method of the three-dimensional shape observation apparatus 100 when setting the acquisition range in order to acquire the height information of the sample 17 will be described.
An interference objective lens 300 having optical characteristics (for example, an observation field) necessary for acquiring a three-dimensional shape image is disposed on the optical axis. In the case where a plurality of interference objective lenses 300 are held by the revolver 45 as shown in FIG. 2, the interference objective lens 300 having desired optical characteristics used when observing the three-dimensional shape of the sample 17 is the optical axis. Placed on top.

  Next, the instruction unit 700 instructs the control main body unit 51 to acquire a three-dimensional shape image on the surface of the sample 17. The control main body 51 drives the first drive unit 22 to rotate the filter switching mechanism 19. The filter switching mechanism 19 arranges a band pass filter 21 on the optical axis. Thereby, the three-dimensional shape observation apparatus 100 forms an optical microscope optical system.

  The control main body 51 controls the white light source 12. The white light source 12 emits white light 13. The white light 13 is reflected by the second half mirror 23, passes through the objective lens 31 and the third beam splitter 36, and irradiates the sample 17. The white light 13 is reflected by the second half mirror 23, passes through the objective lens 31, is reflected by the third beam splitter 36, and irradiates the reference plate 33. The white light 13 reflected from the reference plate 33 and the sample 17 passes through the objective lens 31 and the second half mirror 23 and enters the bandpass filter 21. The bandpass filter 21 transmits only visible light based on the transmittance characteristic. Thereby, the first image sensor 16 images visible light. The first image sensor 16 outputs an output signal to the control main body 51. Thereby, an observation image (hereinafter referred to as an optical microscope observation image) formed based on the optical microscope observation image acquired by the optical microscope optical system is displayed on the display unit 600.

  The control main body 51 adjusts the relative distance by the drive mechanism 40 based on the optical microscope observation image acquired by the optical microscope optical system, focuses the sample 17, adjusts the observation position, and adjusts the focus position.

  Next, the instruction unit 700 instructs the control main body unit 51 to set an acquisition range in order to acquire the height information of the sample 17. Thereby, the control main body 51 sets an upper limit position and a lower limit position. For example, the control main body 51 sets the upper limit position and the lower limit position of the interference objective lens 300 when adjusting the relative distance by moving only the interference objective lens 300 along the optical axis 18. The upper limit position is a position away from the sample 17, and the lower limit position is a position close to the sample 17. For example, the control main body 51 sets the upper limit position and the lower limit position of the stage 200 when only the stage 200 is moved along the optical axis 18 to adjust the relative distance. The upper limit position is a position close to the interference objective lens 300, and the lower limit position is a position away from the interference objective lens 300.

With reference to FIG. 6, the setting method of the acquisition range of height information in this embodiment is demonstrated.
As shown in FIG. 6, the sample 17 has a surface 17a and a surface 17b having different heights. FIG. 6 shows changes in interference intensity in the optical axis direction in the interference optical system corresponding to the surfaces 17a and 17b. In the present embodiment, a case where the surface shape from the surface 17a to the surface 17b in the optical axis direction is observed or the height from the surface 17a to the surface 17b is observed (measured) will be described.

  The control main body 51 focuses on the surface 17a based on the optical microscope observation image acquired by the optical microscope optical system. At that time, the instruction unit 700 sets (specifies) the surface 17a at the lower limit position. The memory 52 stores that the focus position ZL in the optical axis direction corresponding to the surface 17a is the lower limit position.

  Next, the control main body 51 focuses on the surface 17b based on the optical microscope observation image acquired by the optical microscope optical system. At that time, the instruction unit 700 sets (specifies) the surface 17b at the upper limit position. The memory 52 stores that the focus position ZH in the optical axis direction corresponding to the surface 17b is the upper limit position.

  The control main body 51 sets (calculates) the range from the set focus position ZL to the focus position ZH as the acquisition range D1 of the optical microscope optical system. The memory 52 stores this acquisition range D1. When the acquisition range D1 (range from the upper limit position to the lower limit position) is set, the control main body 51 adds the addition range ARL and the addition range ARH stored in advance in the memory 52 to the acquisition range D1. The addition range ARL and the addition range ARH have a desired distance, the addition range ARL is located below the focus position ZL, and the addition range ARH is located above the focus position ZH. The addition range ARL, the addition range ARH, and the acquisition range D1 are continuous. The control main body 51 sets (calculates) the addition result as the acquisition range D2. The acquisition range D2 is a height information acquisition range of the interference optical system. The memory 52 stores this acquisition range D2.

Next, the addition range ARL and the addition range ARH will be described.
When attention is paid to an arbitrary pixel as shown in FIG. 6, the interference intensity in the interference optical system has peaks at the focus position ZH or near the focus position ZH and at the focus position ZL or near the focus position ZL. As the distance from ZH or near focus position ZH and away from focus position ZL or near focus position ZL, it gradually attenuates.

  In order to obtain the peak position of the interference intensity in the interference optical system, the control main body 51 arranges the bandpass filter 20 on the optical axis by the filter switching mechanism 19 to form an interference optical system. At that time, the control main body 51 obtains an output signal from the first image sensor 16 and appropriately sets the peak position of the interference intensity from among the focus position ZH or the focus position ZH and the focus position ZL or the vicinity of the focus position ZL. The calculation is performed for all pixels using a simple algorithm. Thereby, the image processing unit 53 forms a three-dimensional shape image.

  Therefore, the control main body 51 moves the interference objective lens 300 in the optical axis direction by the drive mechanism 40 by the addition range ARL from the focus position ZL of the surface 17a in order to calculate the peak position with respect to the surfaces 17a and 17b. The state of the interference intensity near the focus position ZL or the focus position ZL is acquired from the first image sensor 16. At this time, the control main body 51 acquires the peak position of the interference intensity from the interference position near the focus position ZL or the focus position ZL.

  Further, the control main body 51 moves the interference objective lens 300 in the optical axis direction by the driving mechanism 40 from the focus position ZH of the surface 17b of the sample 17 by the addition range ARH, so that the interference intensity near the focus position ZH or the focus position ZH is increased. The state is acquired from the first image sensor 16. At this time, the control main body 51 acquires the peak position of the interference intensity from the interference position near the focus position ZH or the focus position ZH.

  As described above, the control main body 51 needs to acquire an interference image in the acquisition range D2 when setting the acquisition range of height information in the interference optical system.

  The addition ranges ARL and ARH depend on the coherence distance of the white light source 12. In addition, the interference objective lens 300 can match the same focal lengths of the optical microscope optical system and the interference optical system. However, if the in-focus states do not match, the memory 52 stores the in-focus amount in advance as a table (in-focus correction table). The control main body 51 calculates the acquisition range D2, that is, the acquisition range of height information by the interference optical system, based on the acquisition range D1, the addition ranges ARL and ARH, and the confocal correction table.

  When the setting of the acquisition range of the height information is completed, the control main body 51 starts acquiring the height information of the surface shape of the sample 17. At this time, when the band-pass filter 20 is disposed on the optical axis 18 by the filter switching mechanism 19, the first image sensor 16 images infrared light. Next, the interference objective lens 300 moves the acquisition range D2 in the optical axis direction by the drive mechanism 40, the first image sensor 16 sequentially captures infrared light, and the control main body 51 sequentially acquires the interference image. , Form height information.

  Thereby, the image processing unit 53 forms an optical microscope observation image (surface information) and a height image (three-dimensional shape image), and the display unit 600 displays them.

  As described above, the three-dimensional shape observation apparatus 100 of the present embodiment has two optical systems, that is, an interference optical system and an optical microscope optical system different from the interference optical system, and is acquired by the observation optical system of the optical microscope optical system. By adjusting the observation position of the sample 17 using the optical microscope observation image, the height information acquisition range of the interference optical system can be automatically set.

  Since the interference optical system of the conventional three-dimensional shape observation apparatus has interference fringes in the obtained observation image, it takes time to adjust the observation position and the focus position, the operability is poor, and the sample three-dimensional shape image is displayed. Takes time for acquisition.

  However, the three-dimensional shape observation apparatus 100 of the present embodiment uses an optical microscope observation image acquired by the observation optical system of the optical microscope optical system. The optical microscope observation image is an image having a deep focal depth and no interference fringes because the band-pass filter 21 transmits only visible light. Therefore, the three-dimensional shape observation apparatus 100 according to the present embodiment can easily and quickly adjust the observation position and the focus position using the optical microscope observation image. In addition, the three-dimensional shape observation apparatus 100 of the present embodiment can set the acquisition range of the height information of the interference optical system from the optical microscope observation image acquired by the optical microscope optical system. Thereby, the three-dimensional shape observation apparatus 100 of this embodiment can acquire the three-dimensional shape image of the sample 17 easily in a short time with good operability.

  More specifically, when setting the acquisition range of height information by the interference optical system, the work of searching for interference fringes takes time and effort. In the present embodiment, the height information acquisition range of the interference optical system can be set by the observation optical system of the optical microscope optical system. Therefore, in the present embodiment, it is not necessary to set the acquisition range of height information by the interference optical system. Therefore, in the present embodiment, it is unnecessary to search for interference fringes, and the three-dimensional shape image of the sample 17 can be easily acquired with good operability in a short time.

  In the present embodiment, two types of band-pass filters 20 and 21 having different transmittance characteristics are used, but it is not necessary to limit to this number.

  The filter switching mechanism 19 is not limited to the rotary type. For example, the band-pass filters 20 and 21 mounted on the filter slider may be exchanged by inserting and removing from the optical axis 18. As long as the bandpass filters 20 and 21 can be arranged on the optical axis 18 in this way, the configuration of the filter switching mechanism 19 is not limited.

  Further, the reflection transmittance characteristics of the third beam splitter 36 are shown in FIG. 3, and the transmittance characteristics of the bandpass filters 20 and 21 are shown in FIGS. 4 and 5. However, the present invention is not limited to this, and the desired wavelength is not limited. The region may have a desired reflectance or transmittance. In addition, although the acquisition range is set by the optical microscope, the focus position ZL and then the focus position ZH are set first, but this may be reversed.

Next, a second embodiment according to the present invention will be described with reference to FIGS.
The same members as those in the above-described FIG. 1 (first embodiment) and the three-dimensional shape observation apparatus shown in FIG. 12 are denoted by the same reference numerals, and detailed description thereof is omitted.

FIG. 7 is a configuration diagram of a three-dimensional shape observation apparatus according to the second embodiment.
The stage 200, the interference objective lens 300, and the microscope main body 400 in the present embodiment are substantially the same as the three-dimensional shape observation apparatus 100 shown in FIG. In addition, since the control unit 500, the display unit 600, the instruction unit 700, and the drive mechanism 40 in the present embodiment are substantially the same as those in the first embodiment described above, detailed description thereof is omitted.

  The relative distance in the present embodiment is adjusted by the drive mechanism 40 or manually as in the first embodiment, and the adjustment of the relative distance is not particularly limited.

  Further, in the present embodiment, a plurality of interference objective lenses 300 having different optical characteristics (for example, NA and magnification) may be held by the revolver 45 that is an objective lens placement unit, as in the first embodiment.

  Note that the control main body 51 in the present embodiment includes the illumination intensity of the laser light source 1, the scanning of the two-dimensional scanning mechanism 4, the sensitivity adjustment of the laser light receiving element 11, the illumination intensity of the white light source 12, and the first imaging element 16. It controls sensitivity adjustment, the shutter speed of the first image sensor 16, the operation of rotating the revolver 45 to switch the interference objective lens 300 arranged on the optical axis, and the like.

  Further, the control main body 51 acquires an output signal output from the laser light receiving element 11 when the relative distance changes, and processes this output signal as luminance information (I). As a result, the control main body 51 acquires the luminance information (I) of only the portion in focus on the surface of the sample 17. The control main body 51 calculates the luminance information (I) and forms surface information that is an optical feature of the sample surface from the calculation result. In addition, the control main body 51 acquires an output signal output from the first image sensor 16 when the relative distance changes, and calculates interference image information captured by the first image sensor 16. Further, the control main body 51 forms the height information of the sample 17 acquired by the first image sensor 16 from the interference image information by an operation described later.

  Since the memory 52 and the image processing unit 53 are substantially the same as those in the first embodiment, a detailed description thereof will be omitted. Note that the memory 52 in the present embodiment is in focus with the vertical position, the lower limit position, the acquisition range d1, the acquisition range d2, the subtraction range RRL, the subtraction range RRH, the addition range ARL, and the addition range ARH. Store the correction table.

An operation method of the three-dimensional shape observation apparatus 100 in the present embodiment will be described.
First, an operation method of the confocal laser scanning microscope optical system 400a in this embodiment will be described.
Laser light 2 emitted from the laser light source 1 passes through the polarization beam splitter 3, is reflected by the two-dimensional scanning mechanism 4, and is scanned in the two-dimensional direction with respect to the surface of the sample 17. At that time, the scanned laser light 2 passes through the pupil projection lens 5, is imaged by the first imaging lens 6, and passes through the quarter wavelength plate 7. The laser beam 2 that has passed through the quarter-wave plate 7 is reflected by the first beam splitter 8. The reflected laser beam 2 passes through the second beam splitter 14 and is imaged on the surface of the sample 17 by the objective lens 31. The laser beam 2 passes through the first half mirror 32.

  The transmitted laser beam 2 generates a spot (spot) light by diffraction and irradiates the sample 17.

  The laser light 2 (reflected light) reflected from the sample 17 passes through exactly the same path as that incident on the sample 17 and enters the polarization beam splitter 3. The laser beam 2 incident on the polarization beam splitter 3 is reflected by the polarization beam splitter 3.

  The laser beam 2 reflected by the polarization beam splitter 3 is guided to the second imaging lens 9.

  The laser beam 2 is focused in a dot shape by the second imaging lens 9 and passes through the pinhole 10. As described above, the pinhole 10 is disposed at a position conjugate with the imaging position of the laser beam 2 that has passed through the objective lens 31 (the focal position of the objective lens 31), and the laser beam that is focused on the surface of the sample 17 Pass only 2 As a result, the laser light receiving element 11 is focused on the surface of the sample 17 by the objective lens 31, reflected from the surface of the sample 17, and receives only the laser light 2 that has passed through the pinhole 10. As described above, the laser beam 2 is received by the laser light receiving element 11 without being blocked by the pinhole 10 only when the sample 17 is imaged by the objective lens 31. The laser light receiving element 11 outputs an output signal corresponding to the amount of received laser light 2 to the control main body 51.

  Next, an operation method of the interference optical system 400b in the present embodiment will be described.

  The white light 13 emitted from the white light source 12 is divided by the second beam splitter 14 at a constant division ratio as shown in FIG. The white light 13 reflected downward (on the interference objective lens 300 side) by the division is transmitted through the objective lens 31. The transmitted white light 13 is divided by the first half mirror 32. One white light 13 transmitted through the first half mirror 32 by the division irradiates the sample 17. Further, the other white light 13 reflected by the division irradiates the surface of the reference plate 33. Since the surface of the reference plate 33 is a mirror surface, the white light 13 is reflected by the reference plate 33.

  The white light 13 reflected from the sample 17 passes through the first half mirror 32 and the objective lens 31. Further, the white light 13 reflected from the reference plate 33 is reflected by the first half mirror 32 and passes through the objective lens 31. As a result, the white light 13 reflected from the surface of the sample 17 interferes with the white light 13 reflected from the reference plate 33. The interfering white light 13 (interference light) passes through the second beam splitter 14 and the first beam splitter 8 and then is imaged on the imaging surface of the first imaging element 16 by the third imaging lens 15. Is imaged. The white light 13 has an interference image, and the first image sensor 16 captures an image having an interference image (interference fringes overlap the surface image of the sample 17).

  The first image sensor 16 outputs interference image information included in the captured image to the control main body 51 as an output signal.

  The control main body 51 forms surface information and height information from the acquired output signal. The formed surface information (surface optical image information) and height information are stored in the memory 52. The image processing unit 53 forms an omnifocal image from the surface information stored in the memory 52, and forms a height image from the height information stored in the memory 52. The image processing unit 53 combines the omnifocal image and the height image to form a three-dimensional shape image indicating the three-dimensional shape of the sample 17. The display unit 600 displays at least one of an omnifocal image, a height image, and a three-dimensional shape image.

Next, an operation method of the three-dimensional shape observation apparatus 100 when setting an acquisition range for acquiring height information will be described.
An interference objective lens 300 having optical characteristics (for example, an observation field) necessary for acquiring a three-dimensional shape image is disposed on the optical axis. In the case where a plurality of interference objective lenses 300 are held by the revolver 45 as shown in FIG. 2, the interference objective lens 300 having desired optical characteristics used when observing the three-dimensional shape of the sample 17 is the optical axis. Placed on top.

  Next, the instruction unit 700 instructs the control main body unit 51 to acquire a three-dimensional shape image on the surface of the sample 17. Thereby, the control main body 51 controls the laser light source 1 to emit the laser light 2.

  The laser light 2 emitted from the laser light source 1 irradiates the sample 17 as described above, is reflected from the sample 17, and then received by the laser light receiving element 11. The laser light receiving element 11 outputs an output signal to the control main body 51. As a result, the display unit 600 displays an observation image (hereinafter referred to as an optical microscope observation image) formed based on the optical microscope observation image acquired by the confocal laser scanning microscope optical system 400a.

  The control main body 51 adjusts the relative distance by the drive mechanism 40 based on the optical microscope observation image acquired by the confocal laser scanning microscope optical system 400a, focuses the sample 17, adjusts the observation position, and focuses. Adjust the position.

  Next, the control main body 51 sets an acquisition range in order to acquire the height information of the sample 17. That is, the control main body 51 sets an upper limit position and a lower limit position.

With reference to FIG. 8, the setting method of the acquisition range of height information in this embodiment is demonstrated.
As shown in FIG. 8, the sample 17 has a surface 17a and a surface 17b having different heights. FIG. 8 shows the relationship between the position in the optical axis direction in the confocal laser scanning microscope corresponding to the surfaces 17a and 17b and the amount of laser light 2 passing through the pinhole 10 (hereinafter referred to as IZ curve). Show. FIG. 8 shows a change in interference intensity in the optical axis direction in the interference microscope corresponding to the surfaces 17a and 17b. In the present embodiment, a case will be described in which the surface shape from the surface 17a to the surface 17b in the optical axis direction is observed or the height from the surface 17a to the surface 17b is observed (measured).

  The control main body 51 focuses on the surface 17a based on the optical microscope observation image acquired by the confocal laser scanning microscope optical system 400a. A position in the optical axis direction corresponding to the surface 17a is defined as a focus position ZL. Next, the control main body 51 moves the interference objective lens 300, for example, to the defocus position ZLL where the luminance of the surface 17a is lowered based on the optical microscope observation image, and defocuses it. The defocus position ZLL is located below (on the stage 200 side) in the optical axis direction than the focus position ZL. At that time, the instruction unit 700 sets (specifies) the defocus position ZLL as the lower limit position. The memory 52 stores that the defocus position ZLL is the lower limit position.

  Next, the control main body 51 focuses on the surface 17b based on the optical microscope observation image acquired by the confocal laser scanning microscope optical system 400a. A position in the optical axis direction corresponding to the surface 17b is defined as a focus position ZH. Next, the control main body 51 moves, for example, the interference objective lens 300 to the defocus position ZHH where the luminance of the surface 17b is lowered based on the optical microscope observation image, and defocuses it. The defocus position ZHH is located above (on the interference objective lens 300 side) in the optical axis direction from the focus position ZH. At that time, the instruction unit 700 sets (specifies) the defocus position ZHH as the upper limit position. The memory 52 stores that the defocus position ZHH is the upper limit position of the relative distance.

  The control main body 51 may automatically set the upper limit position and the lower limit position. In this case, the control main body 51 sets the upper limit position and the lower limit position from the displacement of the output signal (the amount of laser light reflected from the sample 17) output from the laser light receiving element 11. When the control main body 51 sets the upper limit position and the lower limit position, the control main body 51 sets only the lower limit position, and then acquires height information from the output signal output from the laser light receiving element 11. Set the upper limit position.

  The control main body 51 sets (calculates) the set range from the defocus position ZLL to the defocus position ZHH as the acquisition range d1 of the confocal laser scanning microscope optical system 400a. The memory 52 stores the acquisition range d1. When the acquisition range d1 (range from the upper limit position to the lower limit position) is set, the control main body 51 subtracts the subtraction range RRL and the subtraction range RRH stored in the memory 52 in advance from the acquisition range d1, and performs this calculation. The addition range ARL and the addition range ARH are added to the result. The subtraction range RRL, the subtraction range RRH, the addition range ARL, and the addition range ARH have a desired distance. The addition range ARL and the addition range ARH in the present embodiment may be the same distance as the addition range ARL and the addition range ARH in the first embodiment described above. The subtraction range RRL and the addition range ARL are located below the focus position ZL, and the subtraction range RRH and the addition range ARH are located above the focus position ZH. The control main body 51 sets (calculates) the calculation result as the acquisition range d2. The acquisition range d2 is a height information acquisition range of the interference optical system 400b. The memory 52 stores the acquisition range d2.

Next, the subtraction range RRL, the subtraction range RRH, the addition range ARL, and the addition range ARH will be described.
As shown in FIG. 8, the IZ curve has peaks at the focus position ZH or near the focus position ZH and at the focus position ZL or near the focus position ZL, and the focus position ZH or near the focus position ZH and the focus position ZL or focus. As the distance from the vicinity of the position ZL increases, it gradually attenuates.

  When the control main body 51 acquires an output signal output from the laser light receiving element 11 in order to acquire the peak position of the IZ curve in the confocal laser scanning microscope optical system 400a, the focus position ZH or the focus position ZH. The peak position is calculated from the vicinity and the focus position ZL or the vicinity of the focus position ZL. Further, the control body 51 calculates luminance information (I) for the peak position. The image processing unit 53 forms an omnifocal image based on these.

  Therefore, in order to calculate the peak position of the IZ curve with respect to the surface of the sample 17, the control main body 51 moves the interference objective lens 300 in the optical axis direction by the drive mechanism 40 at least from the focus position ZL of the surface 17a by the subtraction range RRL. Move to. When the interference objective lens 300 is moved by the subtraction range RRL, the control main body 51 acquires the focus position ZL or the state of the IZ curve near the focus position ZL from the laser light receiving element 11. At this time, the control main body 51 acquires the peak position of the IZ curve from the focus position ZL or the state of the IZ curve near the focus position ZL.

  Similarly, the control main body 51 moves the interference objective lens 300 in the optical axis direction by the drive mechanism 40 at least from the focus position ZH of the surface 17b of the sample 17 by the subtraction range RRH. When the interference objective lens 300 is moved by the subtraction range RRH, the control main body 51 acquires the focus position ZH or the state of the IZ curve near the focus position ZH from the laser light receiving element 11. At that time, the control main body 51 acquires the peak position of the IZ curve from the focus position ZH or the state of the IZ curve near the focus position ZH.

  Thus, the control main body 51 needs to capture the subtraction range RRL and the subtraction range RRH when setting the height information acquisition range d1 in the confocal laser scanning microscope optical system 400a.

  Further, in the acquisition range d2 of the interference optical system 400b, the control main body 51 needs to calculate the peak position of the interference intensity with respect to the surfaces 17a and 17b. Therefore, the control main body 51 moves the interference objective lens 300 in the direction of the optical axis by the drive mechanism 40 from the focus position ZL of the surface 17a by at least the addition range ARL, and changes the state of the interference intensity near the focus position ZL or the focus position ZL. Obtained from one image sensor 16. At this time, the control main body 51 acquires the peak position of the interference intensity from the interference position near the focus position ZL or the focus position ZL.

  Similarly, the control main body 51 moves the interference objective lens 300 in the direction of the optical axis by the drive mechanism 40 from the focus position ZH of the surface 17b by at least the addition range ARH so that the interference intensity near the focus position ZH or the focus position ZH is increased. The state is acquired from the first image sensor 16. At this time, the control main body 51 acquires the peak position of the interference intensity from the interference position near the focus position ZH or the focus position ZH.

  Thus, the control main body 51 needs to capture the subtraction range RRL and the subtraction range RRH when setting the height information acquisition range d2 in the interference optical system 400b.

  Therefore, when calculating the acquisition range d2 set by the interference optical system 400b from the acquisition range d1 set by the confocal laser scanning microscope optical system 400a, the control main body 51 subtracts the subtraction range RRL from the acquisition range d1. The range RRH is subtracted, and the addition range ARL and the addition range ARH are added.

  In the confocal laser scanning microscope optical system 400a, the subtraction range RRL and the subtraction range RRH depend on the NA of the objective lens 31, and in the interference optical system 400b, the addition range ARL and the addition range ARH are coherent with the white light source 12. Depends on distance.

  Similarly to the first embodiment, when a confocal deviation occurs in the confocal laser scanning microscope optical system 400a and the interference optical system 400b, the memory 52 previously stores the amount of confocal deviation as a table (confocal correction table). Remember. The control body 51 determines the acquisition range d1, the subtraction range RRL, the subtraction range RRH, the addition range ARL, the addition range ARH, and the height of the acquisition range d2, that is, the interference optical system 400b based on the in-focus correction table. Calculate the information acquisition range.

  When the setting of the acquisition range of the height information is completed, the control main body 51 starts acquiring the height information of the surface shape of the sample 17. The interference objective lens 300 moves in the acquisition range d2 in the optical axis direction by the drive mechanism 40, the first imaging element 16 sequentially captures white light, the control main body 51 sequentially acquires the interference image, and height information Form.

  The interference objective lens 300 is moved in the acquisition range d1 in the optical axis direction by the drive mechanism 40, the laser light receiving element 11 sequentially receives the laser light 2, and the control main body 51 sequentially acquires the optical microscope observation images. , Forming surface information.

  Note that the operation of moving the interference objective lens 300 in the acquisition range d1 and the operation of moving the interference objective lens 300 in the acquisition range d2 may be performed simultaneously or separately.

  As a result, the image processing unit 53 forms an omnifocal image, a height image, and a three-dimensional shape image as described above. The display unit 600 displays at least one of an omnifocal image, a height image, and a three-dimensional shape image.

  As described above, the three-dimensional shape observation apparatus 100 according to the present embodiment includes two optical systems of the interference optical system 400b and an optical system (confocal laser scanning microscope optical system 400a) different from the interference optical system 400b. Using the optical microscope observation image acquired by the observation optical system of the confocal laser scanning microscope optical system 400a, the adjustment of the observation position of the sample 17, the adjustment of the focus position, and the confocal laser scanning microscope optical system 400a And the acquisition range of the height information of both of the interference optical systems 400b can be automatically set.

  Since the interference optical system of the conventional three-dimensional shape observation apparatus has interference fringes in the obtained observation image, it takes time to adjust the observation position and the focus position, the operability is poor, and the three-dimensional shape image of the sample 17 It takes time for getting.

  However, the three-dimensional shape observation apparatus 100 of the present embodiment uses an optical microscope observation image acquired by the observation optical system of the confocal laser scanning microscope optical system 400a. This optical microscope observation image is an image having a deep focal depth and no interference fringes. Therefore, the three-dimensional shape observation apparatus 100 according to the present embodiment can easily and quickly adjust the observation position and the focus position.

  In addition, the three-dimensional shape observation apparatus 100 according to the present embodiment includes a confocal laser scanning microscope optical system 400a and an interference optical system 400b from an optical microscope observation image acquired by the observation optical system of the confocal laser scanning microscope optical system 400a. The acquisition range of both height information can be set. Thereby, the three-dimensional shape observation apparatus 100 of this embodiment can acquire the three-dimensional shape image of the sample 17 easily in a short time with good operability.

  More specifically, when setting the acquisition range of height information by the interference optical system 400b, the operation of searching for interference fringes takes time and effort. In this embodiment, the height information acquisition range of the interference optical system 400b can be set by the observation optical system of the confocal laser scanning microscope optical system 400a. Therefore, in this embodiment, it is not necessary to set the acquisition range of height information by the interference optical system 400b. Therefore, in the present embodiment, it is unnecessary to search for interference fringes, and a three-dimensional shape image of the sample 17 can be easily acquired with good operability in a short time.

  The acquisition range of the confocal laser scanning microscope optical system 400a is set by first setting the lower limit position (defocus position ZLL) and then the upper limit position (defocus position ZHH), but this may be reversed.

  Further, as shown in FIG. 8, in the present embodiment, the acquisition range d1, the subtraction range RRL, the subtraction range RRH, the addition range ARL, the addition range ARH, and the in-focus correction table stored in the memory 52. From this, the acquisition range d2 is calculated, and acquisition of height information is started. As described above, when the acquisition range d2 is automatically set, the surface 17a, the focus position ZL, and the defocus position ZLL are automatically detected. Therefore, the control main body 51 does not use the subtraction range RRL and the subtraction range RRH, but based on the detected focus position ZL, defocus position ZLL, addition range ARL, addition range ARH, and the in-focus correction table. d2, that is, the height information acquisition range d2 by the optical system in the interference microscope may be calculated.

Next, a third embodiment according to the present invention will be described with reference to FIG.
FIG. 9 is a configuration diagram of a three-dimensional shape observation apparatus according to the third embodiment of the present invention.
The three-dimensional shape observation apparatus (first embodiment) shown in FIG. 1, the three-dimensional shape observation apparatus (second embodiment) shown in FIG. 7, and the three-dimensional shape observation apparatus shown in FIG. The same reference numerals are given to the members, and detailed description thereof is omitted.

  In the three-dimensional shape observation apparatus 100 in the present embodiment, a confocal disk scanning microscope optical system 400c of a confocal disk scanning microscope is arranged instead of the confocal laser scanning microscope optical system 400a in the second embodiment. Has been. Further, in the interference optical system 400b, a fifth beam splitter 37 is arranged instead of the second beam splitter. The reflective transmittance characteristic of the fifth beam splitter 37 is substantially the same as the reflective transmittance characteristic of the third beam splitter 36 shown in FIG. Since the other configuration is substantially the same as that of the second embodiment, detailed description thereof is omitted.

  The confocal disc scanning microscope optical system 400c reflects a white light source 71 that emits white light (second light) 70 that is illumination light, and a white light 70 that is emitted from the white light source 71. A third half mirror 72 that transmits the white light 70 reflected from the sample 17 is sequentially arranged.

  The white light source 71 is, for example, a halogen lamp that emits light in a wide region from the visible region to the infrared region.

  The confocal disk scanning microscope optical system 400 c includes a rotating disk 73 and a rotating disk 73 that allow the reflected light reflected by the third half mirror 72 to pass on the reflected light path of the third half mirror 72. A fifth imaging lens 78 that images the passed white light 70 and a fourth beam splitter 77 that reflects the white light 70 imaged by the fifth imaging lens 78 toward the interference objective lens 300 are sequentially provided. Has been placed.

  The rotating disk 73 is, for example, a nippo disk having a mask pattern. In this rotating disk 73, for example, a plurality of pinholes (not shown) are formed in a plate thickness direction in a spiral shape. White light 70 (visible light) enters the fifth imaging lens 78 by passing through the pinhole.

  The rotary disk 73 is rotated at a desired rotation speed around the central axis 73a by a second drive unit 74 which is, for example, a motor. The second drive unit 74 is controlled by the control main body 51.

  The fourth beam splitter 77 has the reflection transmittance characteristic shown in FIG. 10, reflects substantially 100% visible light, and transmits substantially 100% infrared light.

  Further, the confocal disc scanning microscope optical system 400c includes a fourth imaging lens 75 that forms an image of visible light transmitted through the third half mirror 72 on the transmission optical path of the third half mirror 72; A second imaging element 76 is disposed at the imaging position of the fourth imaging lens 75 and images visible light imaged by the fourth imaging lens 75.

  For example, a CCD camera or a CMOS sensor is used for the second image sensor 76. Further, the second image sensor 76 outputs an output signal to the control main body 51 when imaging visible light.

Next, an operation method of the confocal disc scanning microscope optical system 400c in the three-dimensional shape observation apparatus 100 will be described.
An interference objective lens 300 having optical characteristics (for example, an observation field) necessary for acquiring a three-dimensional shape image is disposed on the optical axis. In the case where a plurality of interference objective lenses 300 are held by the revolver 45 as shown in FIG. 2, the interference objective lens 300 having desired optical characteristics used when observing the three-dimensional shape of the sample 17 is the optical axis. Placed on top.

  Next, the instruction unit 700 instructs the control main body unit 51 to acquire a three-dimensional shape image on the surface of the sample 17. As a result, the control main body 51 controls the white light source 71 to emit white light 70. In addition, the control main body 51 controls the second drive unit 74 to rotate the rotating disk 73 at a desired rotation speed.

  White light 70 emitted from the white light source 71 is reflected by the third half mirror 72. The reflected white light 70 irradiates the rotating disk 73 that is rotating. At that time, the white light 70 passes through the pinhole, is imaged by the fifth imaging lens 78, and enters the fourth beam splitter 77. At that time, only the visible light in the white light 70 is reflected by the fourth beam splitter 77 and is reflected by the fifth beam splitter 37.

  The reflected visible light passes through the fifth beam splitter 37, the objective lens 31, and the third beam splitter 36 and irradiates the sample 17.

  The visible light reflected from the sample 17 passes through the third beam splitter 36, the objective lens 31, and the fifth beam splitter 37 again based on the reflection transmittance characteristic of the third beam splitter 36 described above. Reflected by the fourth beam splitter 77.

  The visible light reflected by the fourth beam splitter 77 passes through the fifth imaging lens 78, passes through the pinhole of the rotating disk 73, passes through the third half mirror 72, and passes through the fourth imaging lens. An image is formed by the lens 75. The formed visible light is imaged by the second image sensor 76. The second image sensor 76 outputs an output signal corresponding to the amount of received visible light to the control main body 51.

  Since the operation method of the interference optical system 400b in the three-dimensional shape observation apparatus 100 of the present embodiment is substantially the same as that of the first or second embodiment, detailed description thereof is omitted.

  As a result, the control main body 51 forms surface information and height information from the output signals acquired from the first image sensor 16 and the second image sensor 76. The formed surface information (surface optical image information) and height information are stored in the memory 52. The image processing unit 53 forms an omnifocal image from the surface information stored in the memory 52, and forms a height image from the height information stored in the memory 52. The image processing unit 53 combines the omnifocal image and the height image to form a three-dimensional shape image indicating the three-dimensional shape of the sample 17. The display unit 600 displays at least one of an omnifocal image, a height image, and a three-dimensional shape image.

  In the present embodiment, the operation method of the three-dimensional shape observation apparatus 100 when setting the acquisition range in order to acquire the height information of the sample 17 and the setting method of the acquisition range of height information are the second Since the confocal disk scanning microscope optical system 400c is arranged instead of the confocal laser scanning microscope optical system 400a in the embodiment, it is substantially the same as in the second embodiment. Therefore, detailed description is omitted.

  As described above, when the confocal disk scanning microscope optical system 400c is arranged instead of the confocal laser scanning microscope optical system 400a, the three-dimensional shape observation apparatus 100 of the present embodiment is the second embodiment described above. The same effect can be obtained.

  Further, the confocal disc scanning microscope optical system 400c can acquire a confocal image with higher resolution than, for example, the optical microscope optical system of the first embodiment. Further, the confocal disk scanning microscope optical system 400c can acquire a confocal image having a color that cannot be acquired by the confocal laser scanning microscope optical system 400a in the second embodiment, for example.

  Further, the confocal disk scanning microscope does not require an expensive optical device such as a galvano scanner arranged in the confocal laser scanning microscope. Therefore, the three-dimensional shape observation apparatus 100 of this embodiment can be made cheaper than the three-dimensional shape observation apparatus 100 of the second embodiment.

  Moreover, the confocal disc scanning microscope optical system 400c can shorten the acquisition time for acquiring the three-dimensional shape of the sample 17 as compared with the confocal laser scanning microscope optical system 400a.

  As described above, the three-dimensional shape observation apparatus 100 according to the present embodiment can obtain the above-described effects different from those of the second embodiment by combining the confocal disk scanning microscope optical system 400c and the interference optical system 400b. it can.

  In addition, although the white light sources 12 and 71 are arrange | positioned in the three-dimensional shape observation apparatus 100 in this embodiment, you may arrange | position only the white light source 71. FIG. In this case, the third half mirror 72 has a reflection transmittance characteristic that reflects and transmits the white light 70 emitted from the white light source 71 with a desired division ratio. On the transmission optical path of the third half mirror 72, a reflecting member such as a mirror that reflects the white light transmitted through the third half mirror 72 toward the fifth beam splitter 37 is disposed.

  Further, in the three-dimensional shape observation apparatus 100 in the present embodiment, the operation of the confocal disc scanning microscope optical system 400c and the interference optical system 400b is separately performed, and the optical path for introducing the white light 70 only to one operating. A switching mechanism may be arranged. Thereby, it is also possible to improve S / N of the interference image which the control main-body part 51 acquires.

  Further, the fourth beam splitter 77 may divide (reflect and transmit) light at a desired ratio with a desired wavelength as a boundary.

  Further, the reflection transmittance characteristic of the third beam splitter 36 is shown in FIG. 3, but is not limited to this. Even if the light is divided (reflected and transmitted) at a desired ratio with a desired wavelength as a boundary, Good.

  As a first modification of the first to third embodiments described above, the observation optical system in the interference optical system and the observation optical system other than the interference optical system have different objective lenses. May be. The interference optical system is, for example, the interference optical system when the band-pass filter 20 of the first embodiment is disposed on the optical axis, or the interference optical system 400b of the second to third embodiments. The optical system other than the interference optical system is, for example, an optical microscope optical system when the band-pass filter 21 of the first embodiment is arranged on the optical axis, or the confocal laser scanning type in the second embodiment. These are the microscope optical system 400a and the confocal disk scan type microscope optical system 400c in the confocal disk scan type microscope in the third embodiment.

  As shown in FIG. 11, an interference objective lens 300 having an objective lens 31a (first objective lens) used in the observation optical system of the interference optical system, and an objective used in the observation optical system other than the interference optical system. The lens 31b (second objective lens) is held by a revolver 45 that is an objective lens arrangement portion. The revolver 45 arranges either the objective lens 31b or the objective lens 31a on the optical axis. The objective lenses 31a and 31b are switched manually or automatically.

  The drive mechanism 40 adjusts by changing the relative distance between the interference objective lens 300 or the objective lens 31b arranged on the optical axis and the sample 17 in the optical axis direction. Specifically, the drive mechanism 40 moves the revolver 45 along the optical axis, and changes the relative distance between the sample 17 and the interference objective lens 300 or the objective lens 31b arranged on the optical axis. Of course, the relative distance may be changed by moving the stage 200 along the optical axis 18.

  In addition, the memory 52 stores a correction value for a field shift caused by the objective lens 31a and the objective lens 31b provided in the interference objective lens 300. The control main body 51 may correct the visual field shift based on the correction value when the objective lens is switched.

  Further, the configuration of the revolver 45 shown in FIG. 11 may be combined with the configuration of the revolver 45 shown in FIG. The revolver 45 may hold a plurality of interference objective lenses 300 having the objective lens 31a and a plurality of objective lenses 31b.

  In the first embodiment, the revolver 45 arranges one desired objective lens 31b on the optical axis. In this state, the control main body 51 sets the observation position adjustment, the focus position adjustment, and the height information acquisition range. Next, the revolver 45 is switched from the objective lens 31b to the objective lens 31a and arranged on the optical axis. The control main body 51 automatically adjusts the visual field shift by controlling the image processing unit 53 or moving the interference objective lens 300 in the plane direction via the stage 200 and the revolver 45 by the drive mechanism 40. After the adjustment, the control main body 51 acquires height information.

  The first to third embodiments use an observation optical system that is an interference optical system and an objective lens 31 that is also used in an observation optical system other than the interference optical system. Therefore, the wavelength range used for the observation optical system of the interference optical system (infrared light wavelength range) is separated from the wavelength range used for the observation optical system of the optical system other than the interference optical system (visible light wavelength range). In this case, it is necessary to arrange a high-performance objective lens that forms an image of all light in a wide wavelength region on the sample 17, and the three-dimensional shape observation apparatus 100 becomes expensive.

  However, since the three-dimensional shape observation apparatus 100 according to the present modification can be provided with the objective lens 31b or the objective lens 31a, it is not necessary to arrange a high-performance objective lens, and the three-dimensional shape observation apparatus 100. Can be made cheaper.

  In the first to third embodiments and the first modification described above, the interference objective lens 300 is a Mirau-type interference objective lens. However, the present invention is not limited to this, and as shown in FIG. The basic configuration, operation, and action of the Michelson type interference objective lens are the same.

FIG. 1 is a configuration diagram of a three-dimensional shape observation apparatus according to the first embodiment. FIG. 2 is a schematic view of a revolver that holds a plurality of interference objective lenses. FIG. 3 is a diagram showing the reflection transmittance characteristics of the third beam splitter 36 in the first embodiment and the fifth beam splitter 37 in the third embodiment. FIG. 4 is a diagram showing the transmittance characteristics of the bandpass filter 20. FIG. 5 is a diagram showing the transmittance characteristics of the bandpass filter 21. FIG. 6 is a diagram showing a change in interference intensity in the optical axis direction in the interference microscope corresponding to the surfaces 17a and 17b. FIG. 7 is a configuration diagram of a three-dimensional shape observation apparatus according to the second embodiment. FIG. 8 is a diagram showing changes in the interference intensity in the optical axis direction in the interference microscope corresponding to the IZ curve and the surfaces 17a and 17b. FIG. 9 is a configuration diagram of a three-dimensional shape observation apparatus according to the third embodiment. FIG. 10 is a diagram showing the reflection transmittance characteristics of the fourth beam splitter 77. FIG. 11 is a schematic diagram of the revolver 45 that holds the objective lens 31b and the interference objective lens 300 having the objective lens 31a. FIG. 12 is a configuration diagram showing a configuration of a conventional three-dimensional shape observation apparatus. FIG. 13 is a configuration diagram of a Michelson-type interference objective lens. FIG. 14 is a diagram showing the reflection transmittance characteristic of the first beam splitter 8. FIG. 15 is a diagram showing the reflection transmittance characteristics of the second beam splitter 14, the second half mirror 23, the first half mirror 32, and the objective beam splitter 34.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Laser light source, 2 ... Laser beam, 3 ... Polarizing beam splitter, 4 ... Two-dimensional scanning mechanism, 5 ... Pupil projection lens, 6 ... 1st imaging lens, 7 ... 1/4 wavelength plate, 8 ... 1st 9 ... second imaging lens, 10 ... pinhole, 11 ... laser light receiving element, 12 ... white light source, 13 ... white light, 14 ... second beam splitter, 15 ... third imaging Lens 16, first image sensor 17, sample 17 a, 17 b, surface 18, optical axis, 19 filter switching mechanism 20, 21 band-pass filter 22, first drive unit 23, first 2 half mirrors, 31 ... objective lens, 32 ... first half mirror, 33 ... reference plate, 36 ... third beam splitter, 37 ... fifth beam splitter, 40 ... drive mechanism, 45 ... revolver, 51 ... Control body 52, memory 5 DESCRIPTION OF SYMBOLS ... Image processing part, 100 ... Three-dimensional shape observation apparatus, 200 ... Stage, 300 ... Interference objective lens, 400 ... Microscope main body, 400a ... Confocal laser scanning microscope optical system, 400b ... Interference optical system, 400c ... Confocal disk Scanning microscope optical system, 500 ... control unit, 600 ... display unit, 700 ... instruction unit.

Claims (11)

A light source that emits light;
An objective lens for irradiating the sample with the light emitted from the light source;
A light splitting member that is disposed between the objective lens and the sample and transmits one of the lights by splitting the light transmitted through the objective lens and reflects the other light;
A reference surface disposed on the optical path divided by the light splitting member and irradiated by the other light reflected from the light splitting member;
An interference objective having
A first observation optical system for observing an interference image by forming an image of the light reflected from the sample that interferes with the light reflected from the reference surface;
An interference optical system having
An optical system different from the interference optical system, wherein the interference objective lens is also used as the interference optical system, and has a second observation optical system for observing the surface information of the sample;
A moving mechanism for adjusting a relative distance between the interference objective lens and the sample in the optical axis direction;
A first acquisition range for acquiring height information of the sample in the optical system based on the surface information observed by the second observation optical system when the moving mechanism adjusts the relative distance. A control unit for calculating a second acquisition range for acquiring height information of the sample in the interference optical system from the calculated first acquisition range;
A storage unit that stores an addition range that is added to the first acquisition range depending on a coherence distance of the interference optical system;
Equipped with,
The three-dimensional shape observation apparatus , wherein the control unit calculates the second acquisition range from the first acquisition range and the addition range . A light source that emits light;
A first objective lens that irradiates the sample with the light emitted from the light source when placed on the optical axis;
A light splitting member that is disposed between the first objective lens and the sample and transmits one of the lights by splitting the light transmitted through the first objective lens and reflects the other light;
A reference surface disposed on the optical path divided by the light splitting member and irradiated by the other light reflected from the light splitting member;
An interference objective having
A first observation optical system that forms an image of the light reflected from the interfering sample and the light reflected from the reference surface to observe an interference image;
An interference optical system having
An optical system different from the interference optical system, having a second objective lens different from the interference objective lens having the first objective lens, and having a second observation optical system for observing the surface information of the sample. The system,
A moving mechanism that adjusts a relative distance in the optical axis direction between the interference objective lens or the second objective lens and the sample arranged on the optical axis;
The second objective lens is disposed on the optical axis, and when the moving mechanism adjusts the relative distance, the surface in the optical system is based on the surface information observed by the second observation optical system. A second acquisition range for calculating a first acquisition range for acquiring the sample height information and acquiring the sample height information in the interference optical system from the calculated first acquisition range. A control unit for calculating
A storage unit that stores an addition range that is added to the first acquisition range depending on a coherence distance of the interference optical system;
Equipped with,
The three-dimensional shape observation apparatus , wherein the control unit calculates the second acquisition range from the first acquisition range and the addition range .   A light source that emits light;
  An objective lens for irradiating the sample with the light emitted from the light source;
  A light splitting member that is disposed between the objective lens and the sample and transmits one of the lights by splitting the light transmitted through the objective lens and reflects the other light;
  A reference surface disposed on the optical path divided by the light splitting member and irradiated by the other light reflected from the light splitting member;
  An interference objective having
  A first observation optical system for observing an interference image by forming an image of the light reflected from the sample that interferes with the light reflected from the reference surface;
  An interference optical system having
  An optical system different from the interference optical system, wherein the interference objective lens is also used as the interference optical system, and has a second observation optical system for observing the surface information of the sample;
  A moving mechanism for adjusting a relative distance between the interference objective lens and the sample in the optical axis direction;
  A first acquisition range for acquiring height information of the sample in the optical system based on the surface information observed by the second observation optical system when the moving mechanism adjusts the relative distance. A control unit for calculating a second acquisition range for acquiring height information of the sample in the interference optical system from the calculated first acquisition range;
  Depends on the optical characteristics of the objective lens and is subtracted from the first acquisition range and is added to the first acquisition range depending on the coherence distance of the interference optical system. A storage unit for storing the addition range;
  Comprising
  The three-dimensional shape observation apparatus, wherein the control unit calculates the second acquisition range from the first acquisition range, the subtraction range, and the addition range.   A light source that emits light;
  A first objective lens that irradiates the sample with the light emitted from the light source when placed on the optical axis;
  A light splitting member that is disposed between the first objective lens and the sample and transmits one of the lights by splitting the light transmitted through the first objective lens and reflects the other light;
  A reference surface disposed on the optical path divided by the light splitting member and irradiated by the other light reflected from the light splitting member;
  An interference objective having
  A first observation optical system that forms an image of the light reflected from the interfering sample and the light reflected from the reference surface to observe an interference image;
  An interference optical system having
  An optical system different from the interference optical system, having a second objective lens different from the interference objective lens having the first objective lens, and having a second observation optical system for observing the surface information of the sample. The system,
  A moving mechanism that adjusts a relative distance in the optical axis direction between the interference objective lens or the second objective lens and the sample arranged on the optical axis;
  The second objective lens is disposed on the optical axis, and when the moving mechanism adjusts the relative distance, the surface in the optical system is based on the surface information observed by the second observation optical system. A second acquisition range for calculating a first acquisition range for acquiring the sample height information and acquiring the sample height information in the interference optical system from the calculated first acquisition range. A control unit for calculating
  Depends on the optical characteristics of the second objective lens, depends on the subtraction range to be subtracted from the first acquisition range, and the coherence distance of the interference optical system, and on the first acquisition range A storage unit for storing an addition range to be added;
  Comprising
  The three-dimensional shape observation apparatus, wherein the control unit calculates the second acquisition range from the first acquisition range, the subtraction range, and the addition range. The three-dimensional shape observation apparatus according to any one of claims 1 to 4, wherein the light source emits the light that is low coherent. The three-dimensional shape observation apparatus according to claim 1 , wherein the optical system is an optical microscope optical system. The three-dimensional shape observation apparatus according to any one of claims 1 to 4, wherein the optical system is a confocal optical system. The three-dimensional shape observation apparatus according to claim 7 , wherein the confocal optical system is a confocal laser scanning microscope optical system or a confocal disk scanning microscope optical system. The storage unit further stores a focusing correction table,
The three-dimensional according to claim 1 , wherein the control unit calculates the second acquisition range from the first acquisition range, the addition range, and the confocal correction table. Shape observation device. The storage unit further stores a focusing correction table,
The said control part calculates the said 2nd acquisition range from the said 1st acquisition range, the said addition range, the said subtraction range, and the said focusing correction table, The Claim 3 or Claim 4 characterized by the above-mentioned. The three-dimensional shape observation apparatus described in 1. An objective lens holding unit for holding the interference objective lens, the second objective lens, and arranging either the interference objective lens or the second objective lens on the optical axis;
The three-dimensional shape observation apparatus according to claim 2 or 4 , characterized by comprising:

Images