Image capturing apparatus

An image capturing apparatus includes an image capturing device that has a plurality of photoelectric converting elements, and a light restricting portion that has a plurality of light inlets and a plurality of light outlets provided to each of the plurality of photoelectric converting elements, that emits, to each of the plurality of photoelectric converting elements, light that can reach each of the plurality of light inlets among light incident on each of the plurality of light outlets and that restricts light that cannot reach each of the plurality of light outlets among the light incident on the light inlets from being emitted to each of the plurality of photoelectric converting elements.

BACKGROUND

1. Technical Field

The present invention relates to an image capturing apparatus.

2. Related Art

Conventionally, an image capturing apparatus that generates an all-in-focus image of a subject has been known. However, a conventional image capturing apparatus has needed to respectively obtain image data on a plurality of focus positions.

PRIOR ART LITERATURE

Patent Document

SUMMARY

In a first aspect, an image capturing apparatus includes an image capturing device that has a plurality of photoelectric converting elements, and a light restricting portion that has a plurality of light inlets and a plurality of light outlets provided to each of the plurality of photoelectric converting elements, that emits, to each of the plurality of photoelectric converting elements, light that can reach each of the plurality of light outlets among light incident on each of the plurality of light inlets, and that restricts light that cannot reach each of the plurality of light outlets among the light incident on the light inlets from being emitted to each of the plurality of photoelectric converting elements.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

FIG. 1schematically shows a usage example of a microscope system5according to a first embodiment. The microscope system5includes a microscope apparatus10and a preparation70. The microscope apparatus10captures an image of a sample90provided on the preparation70. Note that the microscope system5is one example of an image capturing system. The microscope apparatus10is one example of an image capturing apparatus. The sample90is one example of a subject.

The preparation70has a slide glass80and a cover glass60. The cover glass60and the slide glass80have light transparency. The sample90is mounted on the slide glass80. The sample90is provided by being sandwiched between the slide glass80and the cover glass60. Specifically, the slide glass80has a first principle surface81and a second principle surface82that is a surface on an opposite side to the first principle surface81. The sample90is mounted on the first principle surface81of the slide glass80. The sample90is provided by being sandwiched between the cover glass60and the first principle surface81of the slide glass80.

The microscope apparatus10has a mounting surface11to mount the preparation70. The preparation70is mounted on the mounting surface11of the microscope apparatus10. Specifically, the preparation70is mounted on the microscope apparatus10so that the second principle surface82of the slide glass80is in contact with the microscope apparatus10. The microscope apparatus10captures an image of the sample90in a state in which the preparation70is mounted on the mounting surface11.

The microscope apparatus10outputs generated image data to an apparatus such as an output apparatus such as a monitor or a printer, or a recording apparatus such as a storage medium. The microscope apparatus10may include an apparatus being an output destination of the image data. The apparatus being the output destination of the image data may be an external apparatus other than the microscope apparatus10.

In the present embodiment, a direction vertical to the mounting surface11of the microscope apparatus10is defined as a z-axis direction. A direction from the sample90toward the microscope apparatus10is defined as a negative direction along the z axis, and an opposite direction to the direction is defined as a positive direction along the z axis. The x axis, the y axis and the z axis form an orthogonal coordinate system being a right-hand system. In each drawing, to show the direction of each axis of the coordinate system, a coordinate axis may be added to the drawings. Note that for convenience of descriptions, the positive direction along the z axis may be considered as an upper direction and the negative direction along the z axis may be considered as a lower direction.

FIG. 2schematically shows a perspective view of the microscope apparatus10. The microscope apparatus10has an imaging module20. The imaging module20captures an image of the sample90. The imaging module20selects light in a direction substantially along the z axis among light from the first principle surface81of the slide glass80passing through the second principle surface82and toward the imaging module20to capture an image of the sample90.

The imaging module20has a plurality of light inlets including a light inlet120-11. The imaging module20captures an image of the sample90by separately receiving and photoelectrically converting, by a plurality of photoelectric converting elements, light in the direction substantially along the z axis among light respectively incident on the plurality of light inlets including the light inlet120-11. The microscope apparatus10generates image data of the sample90based on a pixel signal obtained by photoelectrically converting by the plurality of photoelectric converting elements in the imaging module20.

FIG. 3schematically shows a cross-sectional view obtained by cutting the imaging module20at a plane parallel to the xz plane.FIG. 4Aschematically shows a cross-sectional view obtained by cutting the imaging module20at a plane parallel to the xy plane.

The imaging module20has a light restricting portion30, a light diffusing portion40and an image capturing unit50. The image capturing unit50is an image capturing device. The image capturing unit50is a solid-state image capturing device such as a CMOS image sensor or a CCD image sensor, for example. The image capturing unit50is a color image sensor of a Bayer type array, for example. The image capturing unit50provides a single-plate image capturing portion.

The image capturing unit50has a color filter portion300, a substrate portion250and a photoelectric converting element portion200. The substrate portion250includes a passivation layer260, a wiring layer280and an insulation layer270. The color filter portion300is provided between the light diffusing portion40and the passivation layer260. In the image capturing unit50, the color filter portion300, the substrate portion250and the photoelectric converting element portion200are provided along the negative direction along the z axis in an order of the color filter portion300, the substrate portion250and the photoelectric converting element portion200.

The color filter portion300has a plurality of color filters including a color filter310-11to a color filter310-1m. The plurality of color filters included in the color filter portion300are arrayed in a matrix of n rows×m columns. Here, n and m may be an integer equal to or more than 2. A color filter positioned on the ith row and the jth column may be called as a color filter310-ijby adding “-ij” to the reference sign of the color filter as a suffix to the reference sign. Also, the plurality of color filters included in the color filter portion300may be collectively called as the color filters310.

Note thatFIG. 4Ashows a cross-sectional view obtained by cutting the color filter portion300at a plane parallel to the xy plane. InFIG. 4A, a letter “R” is added to a color filter that has a spectral characteristic passing light in a red wavelength range through the color filter. A letter “G” is added to a color filter that has a spectral characteristic passing light in a green wavelength range trough the color filter. A letter “B” is added to a color filter that has a spectral characteristic passing light in a blue wavelength range through the color filter. As shown inFIG. 4A, four color filters310of 2 rows×2 columns form one unit lattice of a Bayer array. For example, the color filter310-11, a color filter310-12, a color filter310-21and a color filter310-22form one unit lattice of the Bayer array.

A passivation layer260is positioned on the positive side along the z axis of the substrate portion250to provide a principle surface of the substrate portion250on the positive side along the z axis. A photoelectric converting element portion200is provided on the principle surface of the substrate portion250on the negative side along the z axis.

The photoelectric converting element portion200provides a photoelectric converting portion of the image capturing device. The photoelectric converting element portion200has a plurality of photoelectric converting elements including a photoelectric converting element210-11to a photoelectric converting element210-1m. The plurality of photoelectric converting elements included in the photoelectric converting element portion200are arrayed in a matrix of n rows×m columns. A photoelectric converting element positioned on the ith row and the jth column may be called as a photoelectric converting element210-ijby adding “-ij” to the reference sign of the photoelectric converting element as a suffix to the reference sign. Also, the plurality of photoelectric converting elements included in the photoelectric converting element portion200may be collectively called as the photoelectric converting elements210.

The photoelectric converting element210is one example of each pixel device. The color filter310is provided to the photoelectric converting element210in one-to-one correspondence. Light passing through each color filter310is incident on the respectively-corresponding photoelectric converting element210. For example, light passing through the color filter310-11is incident on the photoelectric converting element210-11, and light passing through the color filter310-12is incident on the photoelectric converting element210-12.

The photoelectric converting element210generates electric charges by using the incident light. The photoelectric converting element210has a photoelectric conversion function for converting the incident light into electric charges. The photoelectric converting element210accumulates the photoelectrically converted electric charges. The microscope apparatus10generates a photoelectric conversion signal by using the electric charges respectively accumulated in the photoelectric converting element210. That is, the microscope apparatus10generates the image data of the subject by using the electric charges accumulated in the photoelectric converting element210.

The light restricting portion30provides a function for emitting, to the image capturing unit50, light in a specific direction (a first direction) among light from the sample90. Specifically, the light restricting portion30emits, toward the image capturing unit50, light in the direction substantially along the z axis among light incident on the light restricting portion30(the z-axis direction is the first direction). Accordingly, the image capturing unit50can receive light selected from among the light from the sample90. The light restricting portion30can provide a similar function to a function of an imaging optical system, without having the imaging optical system such as an imaging lens. The microscope apparatus10does not have an imaging optical system in an optical path from the sample90to the light inlet120. Also, the microscope apparatus10does not have an imaging optical system on an optical path from the sample90to the light diffusing portion40. Also, the microscope apparatus10does not have an imaging optical system on an optical path from the sample90to the image capturing unit50.

The light tube portion100has a plurality of light tubes including a light tube110-11to a light tube110-1M. The plurality of light tubes included in the light tube portion100are arrayed in a matrix of N rows×M columns. Here, N and M may be an integer equal to or more than 2. A light tube positioned on the ith row and the jth column may be called as a light tube110-ijby adding “-ij” to the reference sign of the light tube as a suffix to the reference sign. Also, the plurality of light tubes included in the light tube portion100may be collectively called as the light tubes110.

Each light tube110is one example of the light passing portion. The light tube110has a tubular shape. For example, the light tube110has a cylindrical shape. Each light tube110is a through hole formed in a base body150, for example. Each light tube110is a through hole that penetrates, along the z axis, from a first principle surface151to a second principle surface152of the base body150.

The light tube110-11is formed by a light inlet120-11, a light outlet130-11and a side wall140-11. The side wall140-11connects the light inlet120-11and the light outlet130-11. Similar to the light tube110-11, the light tube110other than the light tube110-11is also formed by the light inlet, the light outlet and the side wall.

Note that when identifying and describing the light inlet, the light outlet and the side wall that form the light tube110-ij, the “-ij” may be added as a suffix to each reference sign for the description. For example, a light tube110-12is formed by a light inlet120-12, a light outlet130-12and a side wall140-12connecting the light inlet120-12and the light outlet130-12. Also, the plurality of light inlets included in the imaging module20may be collectively called as the light inlets120. Also, the plurality of light outlets130included in the imaging module20may be collectively called as the light outlets130. Also, the plurality of side walls140included in the imaging module20may be collectively called as the side walls140.

In this manner, each light tube110is formed by the light inlet120, the light outlet130and the side wall140connecting the light inlet120and the light outlet130. Light being incident on the light inlet120, passing through the light tube110and being emitted from the light outlet130is incident on the light diffusing portion40.

The light diffusing portion40diffuses the incident light and emits the light to the image capturing unit50. The light diffusing portion40has a plurality of light diffusing devices including a light diffusing device180-11to a light diffusing device180-1M. The plurality of light diffusing devices included in the light diffusing portion40are arrayed in a matrix of N rows×M columns. A light diffusing device positioned on the ith row and the jth column may be called as a light diffusing device180-ijby adding “-ij” to the reference sign of the light diffusing device as a suffix to the reference sign. Also, the plurality of light diffusing devices included in the light diffusing portion40may be collectively called as the light diffusing devices180.

The light diffusing device180is provided to the light tube110in one-to-one correspondence. The light diffusing device180is provided on a position on the negative side along the z axis of the light outlet130of the light tube110, the position covering the light outlet130-11. Note that the light diffusing device180may be a light scattering device including a light scattering device such as a microparticle, for example. Also, the light diffusing portion40may also be formed of one piece of sheet-like sheet member such as a light diffusion film.

InFIG. 4A, a position on which the light tube110is projected onto the z-axis direction is shown by dotted lines. Each light tube110is provided correspondingly to four photoelectric converting elements210that correspond to one unit lattice of the Bayer array. Each light passing through the light tube110and reaching the light outlet130is diffused by the light diffusing portion40and is incident on four photoelectric converting elements210of the corresponding unit lattice.

Specifically, as shown inFIG. 4Aand the like, the light tube110-11is provided so that a position of a central axis of the light tube110-1is positioned relative to a central position of the unit lattice formed by the color filter310-11, the color filter310-12, the color filter310-21and the color filter310-22. In this manner, the light tube110-11is provided correspondingly to the color filter310-11, the color filter310-12, the color filter310-21and the color filter310-22. Therefore, the light tube110-11is provided correspondingly to the photoelectric converting element210-11, the photoelectric converting element210-12, the photoelectric converting element210-21and the photoelectric converting element210-22. Light passing through the light tube110-11and reaching the light outlet130-11passes through the light diffusing device180and the color filter310that correspond to the light tube110-11, and is incident on the photoelectric converting element210-11, the photoelectric converting element210-12, the photoelectric converting element210-21and the photoelectric converting element210-22. In this manner, the light being incident on the light inlet120, passing through the light tube110and being emitted from the light outlet130is incident on the photoelectric converting element210that is provided correspondingly to the light tube110.

In this manner, each photoelectric converting element210receives light belonging to a specific wavelength range among the light being emitted from each light outlet130of the corresponding light tube110and being diffused by the light diffusing portion40. For example, the photoelectric converting element210-11and the photoelectric converting element210-22are provided to the light outlet130-11and receive light belonging to the green wavelength range among the light being emitted from the light outlet130-11and being diffused by the light diffusing device180-11. Also, the photoelectric converting element210-12is provided to the light outlet130-11and receives light belonging to the red wavelength range among the light being emitted from the light outlet130-11and being diffused by the light diffusing device180-11. Also, the photoelectric converting element210-21is provided to the light outlet130-11, and receives light belonging to the blue wavelength range among the light being emitted from the light outlet130-11and being diffused by the light diffusing device180-11. By providing the light diffusing portion40, directivity of light emitted from one light tube110can be reduced. Accordingly, the light toward the photoelectric converting element210within one unit lattice of the Bayer array can be approximately uniformized.

Note that each of the photoelectric converting element210-11and the photoelectric converting element210-22is one example of a first photoelectric converting element that is provided to the light outlet130-11and receives light in a first wavelength range among the light being emitted from the light outlet130-11and being diffused by the light diffusing portion40. Also, the photoelectric converting element210-12is one example of a second photoelectric converting element that is provided to the light outlet130-11and receives light in a second wavelength range among the light being emitted from the light outlet130-11and being diffused by the light diffusing portion40. Also, the photoelectric converting element210-21is one example of a third photoelectric converting element that is provided to the light outlet130-11and receives light in a third wavelength range among the light being emitted from the light outlet130-11and being diffused by the light diffusing portion40.

Here, the side wall140is restricted from reflecting light. For example, the side wall140absorbs light being incident on the side wall140. In this manner, in the light restricting portion30, each light inlet120and each light outlet130are connected by the light tube110and the side wall140of each light tube110is restricted from reflecting light. Therefore, for example, among the light incident on the light inlet120-11, substantially only the light that reaches the light outlet130-11by straightly travelling into the light tube110-11without being incident on the side wall140-11is incident on the photoelectric converting element210corresponding to the light tube110-11. Also, the light incident on the light tube110other than the light tube110-11is substantially not incident on the photoelectric converting element210corresponding to the light tube110-11.

Note that the side wall140may be formed of a material that has a low light reflectivity. The side wall140may be formed of a material that provides more light absorptivity than light reflectivity. The color of the side wall140may be black. The side wall140may be formed of carbon and the like. For example, the material forming the base body150may be carbon and the light incident on the side wall140may be absorbed by carbon.

In this manner, the light restricting portion30has a light inlet120and a light outlet130provided to each photoelectric converting element210. The light restricting portion30emits, to each photoelectric converting element210, the light that can straightly travel into and reach each light outlet130among the light incident on each light inlet120, and restricts the light that cannot straightly travel into and reach each light outlet130among the light incident on each light inlet120from being emitted to each photoelectric converting element210.

The light tube110selects light in a direction within a predetermined minute solid angle around a direction along the z axis (the first direction) among light from a corresponding position of the sample90toward the light restricting portion30, and emits the selected light to a corresponding photoelectric converting element210. For that reason, the light incident on each photoelectric converting element210is, so to speak, limited to the light from each portion that is right above each photoelectric converting element210. Therefore, according to the microscope apparatus10, within a plane parallel to the xy plane in space on the subject side, an area of a region for emitting light that can be received by each photoelectric converting element210can be made small. For that reason, according to the microscope apparatus10, so to speak, an image capturing can be performed in a deep depth of field.

Here, the area of the region for emitting light that can be received by each photoelectric converting element210is determined by an aperture diameter D of the light inlet120and of the light outlet130within a flat plane parallel to the xy plane, and a length L of the light tube portion100in the z-axis direction. For example, as F is defined by L/D, the depth of field is determined in accordance with a value of F. As the value of F is large because the length L of the light tube portion100is greater than the aperture diameter D of the light inlet120and the light outlet130, the depth of field becomes deep. Therefore, based on F determined in accordance with the depth of field required by the microscope apparatus10, at least one of the aperture diameter D and L may be designed. For example, L may be determined based on the aperture diameter D that is based on a pitch of the photoelectric converting element210, and the depth of field that is required by the microscope apparatus10.

Note that the light tube110may be filled with air. As another example, the light tube110may be filled with a material having a uniform refractive index. In a case in which the light tube110is filled, it is preferable that in the light inlet120a difference between an incident angle and a refracting angle of light on a boundary surface between a filling medium and an incident-side medium is smaller than a predetermined value. It is preferable that a difference between a refractive index of the filling medium and a refractive index of the incident-side medium is less than a predetermined value. If the incident-side medium is air, it is preferable than the refractive index of the material with which the light tube110is filled is close to that of the air.

Note that in the imaging module20, one light tube110is provided correspondingly to each unit lattice of the Bayer array. As a pixel array of the image capturing unit50, various arrays other than the Bayer array may be applied.

FIG. 4Bshows a modification example in which one light tube is provided to each photoelectric converting element210.FIG. 4Bis an enlarged cross-sectional view of a portion corresponding to a unit lattice including the color filter310-11, the color filter310-12, the color filter310-21and the color filter310-22inFIG. 4A.

As shown inFIG. 4B, the light tube410-11is provided to the color filter310-11. The light tube410-12is provided to the color filter310-12. The light tube410-21is provided to the color filter310-21. The light tube410-22is provided to the color filter310-22. Note that the light tube410-11, the light tube410-12, the light tube410-21and the light tube410-22may be collectively called as light tubes410.

As shown inFIG. 4B, one light tube410is provided to each of the color filter310-11, the color filter310-12, the color filter310-21and the color filter310-22. As described above, the color filter310and the photoelectric converting element210are provided in one-to-one correspondence. Therefore, one light tube410is provided to each photoelectric converting element210.

Each light tube410is provided so that the light outlet of each light tube410is positioned on an inner side of four sides of a corresponding photoelectric converting element210on a plane parallel to the xy plane. On the cross section obtained by cutting the light tube410at a plane parallel to the xy plane, a length of a diameter of the light outlet of each light tube410may be shorter than a length of one side of the photoelectric converting element210. In a case in which the photoelectric converting element210has a shorter side and a longer side, the length of the diameter of the light outlet of each light tube410may be shorter than a length of the shorter side of the photoelectric converting element210on the cross section obtained by cutting the light tube410at a plane parallel to the xy plane. Except these respects, a similar configuration to that of the light tube110can be applied to each light tube410. InFIG. 4B, although only the portion corresponding to the unit lattice is shown, one light tube similar to the light tube410may also be provided to each of another color filter310and a corresponding photoelectric converting element210.

FIG. 4Cshows a modification example in which two light tubes are provided to one photoelectric converting element210.FIG. 4Cis an enlarged cross-sectional view of the portion corresponding to the unit lattice including the color filter310-11, the color filter310-12, the color filter310-21and the color filter310-22inFIG. 4A.

As shown inFIG. 4C, the light tube410-11aand the light tube410-11bare provided to the color filter310-11. The light tube410-12aand the light tube410-12bare provided to the color filter310-12. The light tube410-21aand the light tube410-21bare provided to the color filter310-21. The light tube410-22aand the light tube410-22bare provided to the color filter310-22.

The light tube410-11aand the light tube410-11bare provided so that the light outlet of the light tube410-11aand the light outlet of the light tube410-11bare positioned on an inner side of four sides of the corresponding photoelectric converting element210within a plane parallel to the xy plane. On the cross section obtained by cutting the light tube410at the plane parallel to the xy plane, a length of a diameter of the light outlet of each of the light tube410-11aand the light tube410-11bis at least shorter than a length of one side of the photoelectric converting element210. In a case in which the photoelectric converting element210has a shorter side and a longer side, the length of the diameter of the light outlet of each of the light tube410-11aand the light tube410-11bis at least shorter than a length of the shorter side of the photoelectric converting element210on the cross section obtained by cutting the light tube410at the plane parallel to the xy plane. The light tube410-11aand the light tube410-11bmay be provided along a diagonal line of a quadrangle formed by four sides of the photoelectric converting element210. In a case in which the photoelectric converting element210has a shorter side and a longer side, the light tube410-11aand the light tube410-11bmay be provided along the longer side on the cross section obtained by cutting the light tube410at the plane parallel to the xy plane. Except these respects, each of the light tube410-11aand the light tube410-11bmay have a similar configuration to that of the light tube110.

Also, for the color filter310-12and the corresponding photoelectric converting element210, the light tube410-12aand the light tube410-12brespectively have a similar configuration to that of the light tube410-11aand the light tube410-11b. Also, for the color filter310-21and the corresponding photoelectric converting element210, the light tube410-21aand the light tube410-21brespectively have a similar configuration to that of the light tube410-11aand the light tube410-11b. Also, for the color filter310-22and the corresponding photoelectric converting element210, the light tube410-22aand the light tube410-22brespectively have a similar configuration to that of the light tube410-11aand the light tube410-11b. Note that although inFIG. 4Conly the portion corresponding to the unit lattice including four photoelectric converting elements210is shown, another color filter310and a corresponding photoelectric converting element210may also be provided with two light tubes similar to the light tube410-22aand the light tube410-22b.

With reference toFIG. 4C, a modification example in which two light tubes are provided to one photoelectric converting element210is shown. As another modification example, three or more light tubes may be provided to one photoelectric converting element210. Also, as the modification example described with reference toFIG. 4BandFIG. 4C, in a configuration in which one or more light tubes are provided to each photoelectric converting element210, the light diffusing portion40may be omitted.

Also, a shape of the cross section of the light tube110within the plane parallel to the xy plane is not limited to a circular shape. The light tube110may have various cross-section shapes other than the rectangular shape, the circular shape and the like. Also, the image capturing unit50may have a microlens provided to each photoelectric converting element210.

FIG. 5schematically shows one example of the imaging module2020according to a second embodiment.FIG. 5shows a cross-sectional view of the same cross section as that of theFIG. 3. The imaging module2020further has an aperture plate500in addition to the components included in the imaging module20. Among the components included in the imaging module2020, the components to which the same reference signs as those of the components described with reference to the imaging module20are added have similar configurations to those of the components described with reference to the imaging module20. For that reason, descriptions for the said components may be omitted.

The aperture plate500serves as one light restricting portion together with the light restricting portion30. The aperture plate500is provided apart from the light restricting portion30on the positive side along the z axis of the light restricting portion30. A distance in the z-axis direction from a surface of the aperture plate500on the subject side to the light inlet120is set as L′.

The aperture plate500has a plurality aperture portions including an aperture portion510-11to an aperture portion510-1M. The plurality of aperture portions included in the aperture plate500are arrayed in a matrix of N rows×M columns. An aperture portion positioned on the ith row and the jth column may be called as an aperture portion510-ijby adding “-ij” to the reference sign of the aperture portion as a suffix to the reference sign. Also, the plurality of aperture portions included in the aperture plate500may be collectively called as the aperture portions510.

Each aperture portion510is provided to the light tube110in one-to-one correspondence. Each aperture portion510is provided on an extension that is extended in the positive direction along the z axis from the corresponding light tube110. For example, a center of each aperture portion510is positioned relative to the center of the corresponding light tube110. An aperture diameter of the aperture portion510is D that is the same as that of the light tube110. A length of each aperture plate500in the z direction is shorter than L being the length of the light tube portion100.

Each light tube110emits, to each photoelectric converting element210, the light that can straightly travel into and reach each light outlet130among the light passing through each aperture portion510and being incident on each light inlet120, and restricts the light that cannot straightly travel into and reach each light outlet130-11among the light passing through each aperture portion510and being incident on each light inlet120from being emitted to each photoelectric converting element210. According to the imaging module2020, L in the imaging module20can be effectively increased to L+L′.

Specifically, the depth of field of the imaging module2020is substantially determined by (L+L′)/D. Therefore, according to the imaging module2020, the depth of field can be set substantially deeper compared to a case in which the aperture plate500is not provided. Also, according to the imaging module2020, the length of the light tube110in the z-axis direction that is required for obtaining a certain depth of field can be set shorter compared to the case in which the aperture plate500is not provided.

Note that in the imaging module2020a light wave obtained by superimposing light waves being incident on the aperture portion510and being emitted from the aperture portion510is incident on the light tube110. The microscope apparatus10may correct the obtained image data by image processing based on an inverse function of an optical transfer function obtained by the superimposition of the light waves.

Note that it is preferable that the side wall of the aperture portion510along the z axis does not reflect light, similar to the side wall140of the light tube110. However, the side wall of the aperture portion510-11may also reflect light. Also, one or more aperture plates having the same configuration as that of the aperture plate500may be provided between the aperture plate500and the light tube110.

FIG. 6shows one example of the imaging module4020in a third embodiment. The imaging module4020has a light restricting portion4030, a light diffusing portion4040and an image capturing unit4050. The light restricting portion4030corresponds to the light restricting portion30in the imaging module20. The light diffusing portion4040corresponds to the light diffusing portion40in the imaging module20. The image capturing unit4050corresponds to the image capturing unit50in the imaging module20. Note that when describing the components included in the imaging module4020, a difference from corresponding components among the components included in the imaging module20may be described and descriptions for the other respects may be omitted.

The image capturing unit4050has a color filter portion4300, a substrate portion4250and a photoelectric converting element portion4200. The color filter portion4300corresponds to the color filter portion300. The substrate portion4250corresponds to the substrate portion250. The photoelectric converting element portion4200corresponds to the photoelectric converting element portion200. Note that because the substrate portion4250has a similar layer configuration to that of the substrate portion250, the illustration and the description for the substrate portion4250are omitted.

The substrate portion4250has an upwardly convex curved shape. The substrate portion4250has a curved shape in both cross sections in a direction along the x axis and a direction along the y axis. In this manner, the substrate portion4250has a three-dimensional upwardly convex curved shape. The color filter portion4300and the photoelectric converting element portion4200are formed on the curved front surface of the substrate portion4250. The substrate portion4250is a flexible substrate, for example.

The color filter portion4300has a plurality of color filters including a color filter4310-11to a color filter4310-1m. The plurality of color filters included in the color filter portion4300correspond to the color filter310. The plurality of color filters included in the color filter portion4300have a similar function to that of the color filter310except that the plurality of color filters included in the color filter portion4300are formed on the curved front surface. The plurality of color filters included in the color filter portion4300may be collectively called as the color filters4310.

The photoelectric converting element portion4200has a plurality of photoelectric converting elements including a photoelectric converting element4210-11to a photoelectric converting element4210-1m. The plurality of photoelectric converting elements included in the photoelectric converting element portion4200have a similar function to that of the photoelectric converting element210except that the plurality of photoelectric converting elements included in the photoelectric converting element portion4200are formed on the curved front surface. The plurality of photoelectric converting elements included in the photoelectric converting element portion4200may be collectively called as the photoelectric converting elements4210.

The light tube portion4100has a plurality of light tubes including a light tube4110-11to a light tube4110-1M. The plurality of light tubes included in the light tube portion4100correspond to the light tube110. The plurality of light tubes included in the light tube portion4100have a similar function to that of the light tube110except that the plurality of light tubes included in the light tube portion4100include a light tube along a direction that is substantially not parallel to the z axis. The plurality of light tubes included in the light tube portion4100may be collectively called as the light tubes4110.

The light tube110-11is formed by a light inlet4120-11, a light outlet4130-11and a side wall4140-11. The light inlet4120-11corresponds to the light inlet120-11. The light outlet4130-11corresponds to the light outlet130-11. The side wall4140-11corresponds to the side wall140-11.

Each light tube4110is a through hole formed in the base body4150, for example. For example, each light tube110is a through hole that penetrates from the first surface4151of the base body4150to a second surface4152on an opposite side to the first surface4151. Note that the base body4150corresponds to the base body150. Similar to the base body150, the base body4150may be formed of carbon and the like absorbing light. The first surface4151of the base body4150may have an upwardly convex curved shape. Also, the second surface4152of the base body4150may also have an upwardly convex curved shape.

The light tube4110may have a generally truncated cone shape, for example. A direction of the light tube4110-11is different from a direction of the light tube4110-12. For example, an angular difference between a central axis4190-11of the light tube4110-11and a central axis4190-12of the light tube4110-12is larger than 0 degrees. Note that the central axis4190-11is a straight line connecting the center of the light inlet4120-11to the center of the light outlet4130-11, for example. The central axis4190-12is a straight line connecting the center of the light inlet4120-12and the center of the light outlet4130-12. The central axes of the respective light tubes4110may be radially arranged. It is desired that the direction of the light tube4110is determined so that a range in which any of the photoelectric converting elements4210can receive light can substantially cover the entire range of the field in an angle of view. Also, the maximum value of the angular difference between the direction of the light tube4110and the z axis may be determined in accordance with the angle of view required by the microscope apparatus10.

According to the light restricting portion4030, an incident direction of light beams that can be received by the photoelectric converting element4210is not substantially limited to the z-axis direction only. For that reason, according to the imaging module4020, the image capturing can be performed at a wider angle. Note that instead of the curved image capturing unit50, an image capturing unit in which a number of photoelectric converting elements are arranged may be used, the number of photoelectric converting element portions with a principle surface having a direction different from one another.

FIG. 7schematically shows one example of an imaging module5020according to a fourth embodiment. The imaging module5020has the light restricting portion4030that is described with reference to the imaging module4020, the light diffusing portion40and the image capturing unit50that are described with reference to the imaging module20and the like, and the light guiding device portion5500. When describing the components included in the imaging module5020, differences from corresponding components among the components included in the imaging module20or the imaging module4020may be described and descriptions for the other respects may be omitted.

The light guiding device portion5500is provided between the light restricting portion4030and the light diffusing portion40. The light guiding device portion5500has a plurality of light guiding devices including a light guiding device5510-11to a light guiding device5510-1M. The plurality of light guiding devices included in the light guiding device portion5500are provided to each light outlet4130. A light guiding device corresponding to the light outlet4130on the ith row and the jth column may be called as the light guiding device5510-ijby adding “-ij” to the reference sign of the light guiding device as a suffix to the reference sign. Also, the plurality of light guiding devices included in the light guiding device portion5500may be collectively called as the light guiding devices5510.

Each light guiding device5510is, for example, an optical fiber. The light guiding device5510guides each light emitted from each light outlet4130to each light diffusing device180. The light guided to the light diffusing device180by the light guiding device5510passes through the light diffusing device180, is incident on the image capturing unit50and is incident on the corresponding photoelectric converting element210. In this manner, the light guiding device5510guides each light emitted from each light outlet4130to each photoelectric converting element210. For example, the light guiding device5510-11guides each light emitted from each light outlet4130-11to each corresponding photoelectric converting element210. Note that in a case in which the light guiding device5510substantially has a property of diffusing light, a configuration in which the light diffusing portion40is not included may be applied to the light guiding device5510.

According to the imaging module5020, an image capturing can be performed at a wider angle by using a flat plate-like image capturing unit50. Note that a configuration in which a similar light guiding device to the light guiding device5510is further included can also be applied to the imaging module20and the imaging module2020.

In the present embodiment, the microscope apparatus10is used as one example of the image capturing apparatus. However, the image capturing apparatus is not limited to the microscope apparatus. The image capturing apparatus is a concept including various electronic devices having an image capturing function, such as a finger print sensor apparatus, a scanner, a monitor camera, a smart phone having an image capturing function, a mobile phone having an image capturing function and a mobile terminal having an image capturing function.

While the embodiments of the present invention have been described, the technical scope of the invention is not restricted to the above described embodiments. It is apparent to persons skilled in the art that various alterations and improvements can be added to the above-described embodiments. It is also apparent from the scope of the claims that the embodiments added with such alterations or improvements can be included in the technical scope of the invention.

EXPLANATION OF REFERENCES