Optical system, lens device, imaging device, and projection device

Abstract

To provide an optical system that can form an optical condition according to a purpose, and a lens device, an imaging apparatus, and a projector having the optical system.SOLUTION: An imaging apparatus 100 includes an objective lens 1 and an optical element 2 located on the opposite side of the objective lens 1 to the side where an object is arranged. The optical element 2 includes: a rotatably supported rotary member 21; and a plurality of filters 22A to 22D formed in the rotary member 21, the filters being optically arranged in positions perpendicular to the optical axis 1J of the objective lens 1 and having different optical transmission characteristics. The rotary axis 21J of the rotary member 21 is not parallel to the optical axis 1J of the objective lens 1.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an optical system, a lens device, an imaging device, and a projection device. [Background technology]

[0002] Patent Document 1 describes a multispectral lighting environment imaging device that includes an imaging lens that captures reflected light of the lighting environment by a convex mirror and forms an image, a filter turret that modulates the spectral characteristics of the light by sequentially positioning multiple filters held on the same circumference in the optical path of the imaging lens, and an image sensor that is positioned at the imaging position of the imaging lens and captures the reflected light of the lighting environment as an image signal.

[0003] Patent document 2 describes a calibration camera that includes a photographing optical system with a fisheye lens positioned on the subject side, a turret plate with six holes evenly spaced in the circumferential direction, curved filters attached to five of the six holes in the turret plate, a turret shaft that rotatably supports the turret plate, and a motor that rotates the turret plate around the turret shaft.

[0004] Patent Document 3 describes a transmitted light focusing device having a turret on which a plurality of objective lenses are arranged.

[0005] Patent Document 4 describes an optical device including a turret with an objective lens attachment part on which five objective lenses with different magnifications can be attached. The rotation axis of this turret is inclined at 15 degrees with respect to the observation optical axis in order to keep objective lenses other than the objective lens used for observation away from the observation sample.

[0006] Patent Document 5 describes a confocal laser scanning microscope having a filter turret that holds multiple notch filters and a roughly disk-shaped mirror turret that holds multiple excitation dichroic mirrors, with the optical axis of the mirror turret positioned at a predetermined angle with respect to the optical path.

[0007] Patent Document 6 describes an epifluorescence microscope equipped with a filter cassette having a turret-type switching mechanism. This turret has a truncated pyramid shape with eight pyramidal faces centered on the rotation axis, with a dichroic mirror on each pyramidal face and an absorption filter on the horizontal face. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2007-042318 A [Patent Document 2] JP 2006-276433 A [Patent Document 3] Special Publication No. 2019-523897 [Patent Document 4] Japanese Patent Application Publication No. 11-095087 [Patent Document 5] JP 2015-014755 A [Patent Document 6] JP 2001-208981 A Summary of the Invention [Problem to be solved by the invention]

[0009] An object of the present invention is to provide an optical system capable of forming optical conditions according to an application, and a lens device, an imaging device, and a projection device that include the optical system. [Means for solving the problem]

[0010] An optical system according to one aspect of the present invention is an optical system arranged on the opposite side of an objective lens from an object side, the optical system comprising: a rotating member supported to be rotatable; and a plurality of light transmission regions having different light transmission characteristics formed on the rotating member and arranged so as to be able to be arranged at positions intersecting an optical axis of the objective lens, the rotating axis of the rotating member being configured to be non-parallel to the optical axis of the objective lens. the objective lens is a lens having a total angle of view exceeding 180 degrees, and the rotating member is shaped to prevent a light beam incident on the outermost edge of an effective diameter range of the objective lens or a light beam projected from the outermost edge of an effective diameter range of the objective lens from being blocked by at least one of the light transmitting region and the rotating member. It is something. Effect of the Invention

[0011] According to the present invention, it is possible to provide an optical system capable of forming optical conditions according to an application, and a lens device, an imaging device, and a projection device that include the optical system. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic diagram showing a schematic configuration of an image pickup apparatus 100 according to an embodiment of the image pickup apparatus of the present invention. [Diagram 2] 2 is a schematic diagram of the optical element 2 shown in FIG. 1 as viewed in the direction of the rotation axis from the objective lens 1 side. [Diagram 3] 2 is a schematic diagram of a rotating member 21 shown in FIG. 1 as viewed in a direction Z2. [Figure 4] 4 is a schematic diagram of a rotating member 21 shown in FIG. 3 as viewed in a direction X1. [Diagram 5] 4 is a schematic diagram of the rotating member 21 shown in FIG. 3 as viewed in a direction X2. [Figure 6] 4 is a schematic diagram of the rotating member 21 shown in FIG. 3 as viewed in a direction Y2. [Figure 7] 4 is a schematic diagram of the rotating member 21 shown in FIG. 3 as viewed in a direction Y1. [Figure 8] 3 is a schematic diagram of a rotating member 21 shown in FIG. 2 as viewed in the direction of the rotation axis from the objective lens 1 side. [Figure 9] 3 is a schematic diagram showing a modified example of the rotating member 21 shown in FIG. 2. FIG. [Figure 10] 3 is a schematic diagram showing a modified example of the rotating member 21 shown in FIG. 2. FIG. [Figure 11] 3 is a schematic diagram showing a modified example of the rotating member 21 shown in FIG. 2. FIG. [Figure 12] FIG. 2 is a diagram showing a modified example of the imaging device 100 shown in FIG. 1, and is a schematic cross-sectional view corresponding to FIG. 1 in which the rotating member 21 is configured in a flat plate shape. [Figure 13] FIG. 2 is a schematic diagram for explaining the design conditions of the optical element 2, and corresponds to FIG. [Figure 14] 1. FIG. 4 is a schematic cross-sectional view showing a modified example of the optical element 2 in the imaging device 100 shown in FIG. [Figure 15] FIG. 1 is a cross-sectional view showing a schematic configuration of an imaging device 200 according to another embodiment of the imaging device of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Fig. 1 is a schematic diagram showing a schematic configuration of an imaging device 100 which is one embodiment of the imaging device of the present invention. The imaging device 100 is an imaging unit of a digital camera or an endoscope, etc., and has an objective lens 1 as an optical element arranged closest to the subject. Fig. 1 is a schematic diagram showing a cross section including an optical axis 1J of this objective lens 1.

[0014] Hereinafter, the direction in which the optical axis 1J of the objective lens 1 extends is referred to as the optical axis direction Z. In the optical axis direction Z, the direction from the imaging device 100 toward the subject is referred to as the direction Z1, and the opposite direction of the direction Z1 is referred to as the direction Z2. Two directions perpendicular to the optical axis direction Z and perpendicular to each other are referred to as the direction X and the direction Y. The direction Y constitutes the first direction, and the direction X constitutes the second direction. One side of the direction X is referred to as the direction X1, and the other side of the direction X is referred to as the direction X2. One side of the direction Y is referred to as the direction Y1, and the other side of the direction Y is referred to as the direction Y2. The cross section of the imaging device 100 shown in FIG. 1 is a surface parallel to the XZ plane indicated by the coordinate axes extending in the optical axis direction Z and the coordinate axes extending in the direction X.

[0015] As shown in FIG. 1, the imaging device 100 includes a lens device 3 including at least an objective lens 1 and an optical element 2, an imaging element 4 including a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor, etc., which images a subject through the lens device 3, a driving unit 6 including an actuator such as a motor or a solenoid, a control unit 5 including a processor that controls the imaging element 4 and the driving unit 6 and processes signals output from the imaging element 4, and a housing 7 that accommodates the lens device 3, the imaging element 4, the driving unit 6, and the control unit 5. Although not shown in FIG. 1, other optical elements such as one or more lenses, prisms, mirrors, or diaphragms may be disposed between the objective lens 1 and the imaging element 4. An optical system is formed by at least the optical element 2 among the other optical elements and the optical element 2, and the lens device 3 is formed by this optical system and the objective lens 1.

[0016] The objective lens 1 is a so-called fisheye lens with a total angle of view exceeding 180 degrees. Light ray 1R shown in Fig. 1 indicates a light ray that is incident on the outermost edge of the effective diameter range of the objective lens 1 among the light rays from a subject that the objective lens 1 can collect.

[0017] The optical element 2 is for switching, among multiple patterns, the amount, wavelength, spatial frequency, or vibration direction of the subject light to be collected by the objective lens 1 and reach the image sensor 4. The optical element 2 is provided so that a part of it can be positioned on the optical path of the light passing through the objective lens 1 and reaching the image sensor 4.

[0018] The optical element 2 includes a rotating member 21 that is rotatably supported and has a non-flat plate shape (having a substantially V-shaped cross section in the example of FIG. 1), four light transmission areas (filters 22A to 22D described below) with different light transmission characteristics that are formed on the rotating member 21 and are configured to be positionable at positions intersecting the optical axis 1J of the objective lens 1, and a cylindrical shaft member 23 that forms a rotation shaft 21J of the rotating member 21. The light transmission characteristics refer to the light transmittance, the wavelength of the transmitted light, the spatial frequency of the transmitted light, the vibration direction of the transmitted light, etc.

[0019] The shaft member 23 is fixed to the rotating member 21, and is rotationally driven by power from an actuator included in the driving unit 6. The driving unit 6 is supported by the housing 7. In other words, the rotating member 21 is rotatably supported by the housing 7 via the driving unit 6.

[0020] The optical axis 1J of the objective lens 1 and the rotation axis 21J of the rotating member 21 are not parallel. In other words, the optical axis direction Z and the direction in which the rotation axis 21J extends (hereinafter also referred to as the rotation axis direction) are different. The fact that the two axes are not parallel means that the two axes do not exist on the same plane, or that the two axes exist on the same plane and the two axes or their extensions intersect. In the example of FIG. 1, the optical axis 1J and the rotation axis 21J are on the same plane (XZ plane), and the rotation axis 21J is inclined toward the direction X2 with respect to the optical axis 1J, so that the optical axis 1J and the rotation axis 21J intersect on the imaging element 4 side of the objective lens 1. The optical axis 1J and the rotation axis 21J do not need to be on the same plane, and may be on the XZ plane with different positions in the direction Y. 9, the rotation axis 21J may intersect with the XZ plane including the optical axis 1J. That is, the optical axis 1J and the rotation axis 21J may be configured to have a twisted relationship.

[0021] Fig. 2 is a schematic diagram of the optical element 2 shown in Fig. 1 as viewed in the rotation axis direction from the objective lens 1 side. When viewed in the rotation axis direction, the rotating member 21 has a circular ring shape. A shaft member 23 is fixed to the inner periphery of the rotating member 21, and the central axis of the shaft member 23 forms a rotation axis 21J.

[0022] The rotating member 21 has four openings 21k that penetrate the rotating member 21 and are arranged at equal intervals in the circumferential direction. A flat filter (filter 22A, filter 22B, filter 22C, and filter 22D) is fitted into each of the four openings 21k. The four filters are composed of four ND (Neutral Density) filters with different light transmittances, four spectral filters with different light transmission wavelengths, four optical low-pass filters with different spatial frequencies of transmitted light, or four polarizing filters with different vibration directions of transmitted light. The four filters may be composed of a combination of two or more of the ND filters, the spectral filters, the optical low-pass filters, and the polarizing filters. In addition, one of the four filters may be deleted to leave the opening 21k as it is, or one of the four filters may be changed to glass that has almost the same incident light and transmitted light. The filter, the glass, and the opening 21k that does not include the filter and the glass each constitute a light transmitting region formed in the rotating member 21.

[0023] Every time the rotating member 21 rotates 90 degrees around the rotating shaft 21J, one of the filters 22A, 22B, 22C, and 22D is disposed on the optical path including the optical axis 1J in a state intersecting (orthogonal in the example of FIG. 1) the optical axis 1J of the objective lens 1. Therefore, by changing the type of filter (light transmitting region) that is caused to intersect with the optical axis 1J, it becomes possible to image the subject according to the purpose.

[0024] For example, by using an imaging element 4 capable of capturing color images and providing four ND filters with different light transmittances as the four filters formed on the rotating member 21, an imaging device 100 that can respond to changes in the brightness of the subject can be realized.

[0025] Furthermore, for example, by using an imaging element 4 capable of imaging from the ultraviolet to infrared ranges, and providing the four filters formed on the rotating member 21 with a spectral filter that transmits red light to obtain a visible light image, a spectral filter that transmits green light, and a spectral filter that transmits blue light, as well as a spectral filter for obtaining a fluorescent image, the imaging device 100 can be applied to an endoscope to switch between normal observation and special light observation.

[0026] FIG. 3 is a schematic diagram of the rotating member 21 shown in FIG. 1 as viewed in direction Z2. FIG. 4 is a schematic diagram of the rotating member 21 shown in FIG. 3 as viewed in direction X1. FIG. 5 is a schematic diagram of the rotating member 21 shown in FIG. 3 as viewed in direction X2. FIG. 6 is a schematic diagram of the rotating member 21 shown in FIG. 3 as viewed in direction Y2. FIG. 7 is a schematic diagram of the rotating member 21 shown in FIG. 3 as viewed in direction Y1. FIG. 8 is a schematic diagram of the rotating member 21 shown in FIG. 2 as viewed in the rotation axis direction from the objective lens 1 side. In FIGS. 3 to 8, for understanding the structure, filters are removed from three of the four openings 21k formed in the rotating member 21.

[0027] 3 to 8, the rotating member 21 has an annular plate-shaped annular portion 21A in which openings 21k are formed side by side in the circumferential direction, and a cylindrical shaft portion 21B formed inside the annular portion 21A and supporting a shaft member 23 (in other words, a rotating shaft 21J) therein, and is a member having a truncated cone shape on the surface facing the objective lens 1. A circular opening 21Bk is formed in the center of the rotating member 21, and the shaft member 23 is supported by the inner peripheral wall of this opening 21Bk.

[0028] 3, 4, and 8, the position of the inner peripheral edge portion 21Aei in the rotation axis direction of the annular portion 21A when viewed in the rotation axis direction is located closer to the objective lens 1 than the position of the outer peripheral edge portion 21Aeo in the rotation axis direction when viewed in the rotation axis direction. In other words, the annular portion 21A is configured to be inclined toward the opposite side to the objective lens 1 side (direction away from the objective lens 1) with respect to a plane perpendicular to the rotation axis 21J.

[0029] The annular portion 21A is a plate having a substantially constant thickness, and has an opening 21k penetrating in the thickness direction. Since the annular portion 21A has an inclined configuration as described above, the filters fitted in the openings 21k formed in the annular portion 21A are also inclined along the openings 21k. That is, the light entrance surface and the light exit surface of each of the filters 22A, 22B, 22C, and 22D are inclined in the same direction (away from the objective lens 1) with respect to a plane perpendicular to the rotation axis 21J.

[0030] The optical element 2 is rotationally driven under the control of the control unit 5 so that any one of the filters 22A, 22B, 22C, and 22D is inserted at a position perpendicular to the optical axis 1J. As shown in Fig. 1, when any one of the filters is disposed on the optical path including the optical axis 1J, the light entrance surface and the light exit surface of the filter are perpendicular to the optical axis 1J. This allows the subject light collected by the objective lens 1 to be appropriately adjusted by the filter and guided to the image sensor 4.

[0031] In the optical element 2, the shape of the annular portion 21A in the state shown in FIG. 8 may not be a circular ring, and may be, for example, an elliptical ring. The rotating member 21 may be a member whose surface on the objective lens 1 side is shaped like a truncated pyramid. Alternatively, the rotating member 21 may be configured with a shape in which the area between the areas where the openings 21k are formed is partially cut out, as in the modified example of the rotating member 21 shown in FIG. 10. In order to reduce the size of the rotating member 21, the openings 21k may not be holes, but may be cut out from the outer circumferential edge portion 21Aeo of the annular portion 21A radially inward of the annular portion 21A, as in the modified example of the rotating member 21 shown in FIG. 11.

[0032] In the imaging device 100 configured as described above, the optical axis 1J of the objective lens 1 and the rotation axis 21J of the rotation member 21 are not parallel. In a reference configuration in which the optical axis 1J and the rotation axis 21J are parallel, the rotation member 21 is extended to a position indicated by the broken line CP in FIG. 1, for example. Therefore, compared to this reference configuration, the imaging device 100 can reduce the width in the direction X of the area occupied by the rotation member 21 in the housing 7 (width Dm in FIG. 1). As a result, the imaging device 100 can be made smaller. In particular, when the optical axis 1J and the rotation axis 21J are in a twisted relationship, it becomes easy to design the driving unit 6 for rotationally driving the rotation member 21 to prevent interference between the optical path of the light passing through the objective lens 1 and the driving unit 6, which can facilitate further miniaturization and reduction in manufacturing costs.

[0033] Even if the rotating member 21 is flat, it is possible to obtain the effect of miniaturization due to the optical axis 1J and the rotation axis 21J being non-parallel. FIG. 12 is a diagram showing a modification of the imaging device 100 shown in FIG. 1, and is a schematic cross-sectional diagram corresponding to FIG. 1 in which the rotating member 21 is flat. In the example of FIG. 12, the rotating member 21 is a disk-shaped member with the rotation axis 21J provided at the center. The filters fitted in the four openings 21k of the rotating member 21 are provided at an incline in a direction away from the objective lens 1 with respect to the surface of the rotating member 21 on the objective lens 1 side in the rotation axis direction (i.e., a surface perpendicular to the rotation axis 21J). Even with the configuration shown in FIG. 12, the width of the area occupied by the rotating member 21 in the direction X (width Dm in FIG. 12) in the housing 7 can be made smaller than the reference configuration in which the optical axis 1J and the rotation axis 21J are parallel.

[0034] In addition, in the imaging device 100, since the optical axis 1J and the rotation axis 21J are not parallel, it is possible to design the optical element 2 so that at least one of the rotation member 21 and each filter does not block the light ray 1R incident on the objective lens 1, as shown in FIG. 1 or FIG. 12. In a reference configuration in which the optical axis 1J of the objective lens 1 and the rotation axis 21J of the rotation member 21 are parallel, the light ray 1R intersects with the optical element 2 at a position close to the objective lens 1 in the optical axis direction Z. For this reason, if an objective lens 1 having a total angle of view exceeding 180 degrees is used, the total angle of view may not be effectively utilized. According to the imaging device 100, even if an objective lens 1 having a total angle of view exceeding 180 degrees is used, it is possible to capture an image of a subject in the total angle of view without omission.

[0035] Moreover, in the imaging device 100, the rotating member 21 is non-flat (specifically, a plate shape warped in the rotation axis direction). With this configuration, the width Dm can be made smaller than the configuration in Fig. 12. Furthermore, since the rotating member 21 is non-flat, it is possible to reduce the thickness and weight of the rotating member 21, thereby reducing the manufacturing cost of the imaging device 100 and making the imaging device 100 lighter.

[0036] Next, preferred conditions for preventing at least one of the rotating member 21 and each filter from blocking the light ray 1R incident on the objective lens 1 will be described. The radially outer edge of the rotating member 21 in the optical element 2 can be formed inside the filters as shown in FIG. 11. Therefore, by preventing each filter provided on the rotating member 21 from blocking the light ray 1R incident on the objective lens 1, it is also possible to prevent the rotating member 21 from blocking the light ray 1R incident on the objective lens 1. FIG. 13 is a schematic diagram for explaining the design conditions of the optical element 2, and corresponds to FIG. 1.

[0037] As shown in FIG. 13, a state in which one filter (filter 22A in the example of FIG. 13) intersects perpendicularly to the optical axis 1J is defined as an observation state when viewed in the direction Y. In this observation state, the distance between the edge 1e on the optical element 2 side of the light passing range on the surface of the object side of the objective lens 1 and the edge on the objective lens 1 side of the filter 22A intersecting the optical axis 1J is defined as L. Also, the effective diameter of the objective lens 1 is defined as D1. Further, the length in the direction X of the filter 22A intersecting the optical axis 1J is defined as d2. Also, the distance between the edge 22Ae on the rotation axis 21J side and the objective lens 1 side of the filter 22A intersecting the optical axis 1J and the edge 22Be on the rotation axis 21J side and the objective lens 1 side of the filter 22B not intersecting the optical axis 1J is defined as d3. The distance d3 corresponds to the sum of the distance d3a between the edge 22Ae and the rotation axis 21J and the distance between the edge 22Be and the rotation axis 21J equal to this distance d3a. That is, the distance d3 = 2×d3a. Also, the angle formed by the optical axis 1J and the rotation axis 21J is defined as θ. Also, half of the total angle of view of the objective lens 1 is defined as α.

[0038] When such definitions are made, in the observation state shown in FIG. 13, the distance L2 between the edge 22Beo on the objective lens 1 side and the outer peripheral edge side of the rotating member 21 of the filter 22B not intersecting the optical axis 1J and the edge 1e of the objective lens 1 is expressed by the following formula (A). Also, when the intersection point of the straight line passing through the edge 22Beo and extending in the optical axis direction Z and the light ray 1R is defined as P, the distance L1 between the edge 1e of the objective lens 1 and the intersection point P is expressed by the following formula (B).

[0039] L2 = |L + d3*sin(θ) + d2*sin(2θ)| ···(A) L1 = |{d2 / 2 + d3*cos(θ) + d2*cos(2θ) - D1 / 2}*cos(α)| ···(B)

[0040] By designing the objective lens 1 and the optical element 2 such that L1 and L2 obtained from formula (A) and formula (B) satisfy the relationship L1 < L2, it becomes possible to prevent the light ray 1R from being blocked by the optical element 2.

[0041] In the above description, four filters (light transmitting regions) are provided in the rotating member 21, but it is sufficient that there are at least two light transmitting regions in the rotating member 21. For example, the rotating member 21 may have a configuration in which the two openings 21k (for example, the two openings 21k arranged vertically in FIG. 2) that face each other across the rotation axis 21J and the filters fitted into these two openings 21k are deleted.

[0042] FIG. 14 is a schematic cross-sectional view showing a modified example of the optical element 2 in the imaging device 100 shown in FIG. 1. The rotating member 21 of the optical element 2 shown in FIG. 14 is configured by, for example, bending a flat plate extending in the direction X and perpendicular to the optical axis 1J in a direction away from the objective lens 1 near the rotating shaft 21J. The rotating member 21 has two openings 21k formed at positions facing each other across the rotating shaft 21J, and a filter 22A is fitted only in one of the two openings 21k. When the rotating member 21 rotates 180 degrees around the rotating shaft 21J from the state of FIG. 14, the opening 21k in which the filter is not fitted reaches the broken line position in the figure. In this state, the light collected by the objective lens 1 passes through the opening 21k as it is and reaches the imaging element 4. On the other hand, in the state shown in FIG. 14, the light collected by the objective lens 1 passes through the filter 22A and reaches the imaging element 4.

[0043] 14, it is possible to reduce the size and cost of the imaging device 100. Also, a configuration in which the light ray 1R is not blocked by the optical element 2 is possible.

[0044] Fig. 15 is a cross-sectional schematic diagram showing a schematic configuration of an imaging device 200 which is another embodiment of the imaging device of the present invention. The imaging device 200 includes an imaging device 100A having the same configuration as the imaging device 100 shown in Fig. 1, and an imaging device 100B having the same configuration as the imaging device 100 shown in Fig. 1. The lens device 3 included in the imaging device 100A constitutes a first lens device, and the lens device 3 included in the imaging device 100B constitutes a second lens device, and the first lens device and the second lens device constitute the lens device.

[0045] The imaging devices 100A and 100B are arranged side by side at a distance in the direction X. The optical axis 1J of the objective lens 1 of the imaging device 100A and the optical axis 1J of the objective lens 1 of the imaging device 100B are parallel, and Fig. 15 shows a straight line LS extending in the optical axis direction Z at a position midway between these two optical axes 1J. The imaging devices 100A and 100B are arranged in a line-symmetric relationship with respect to the straight line LS.

[0046] The control unit 5 of the imaging device 100A and the control unit 5 of the imaging device 100B are configured to be able to communicate with each other. The housing 7 may be common to the imaging device 100A and the imaging device 100B. The control unit 5 may be common to the imaging device 100A and the imaging device 100B.

[0047] According to this imaging device 200, a wide range of subjects can be captured by two pairs of lens devices 3 and imaging elements 4 arranged with parallax. This makes it possible to record a stereoscopic image by processing the images captured by the two imaging elements 4.

[0048] 15, it is also possible to invert the imaging device 100A so that the end on the X1 direction side and the end on the X2 direction side are reversed, and to invert the imaging device 100B so that the end on the X1 direction side and the end on the X2 direction side are reversed. In contrast to this modified configuration, as shown in FIG. 15, a configuration in which the rotation axis 21J of each of the imaging devices 100A and 100B is disposed outside the optical axis 1J of each of the imaging devices 100A and 100B can be configured to easily reduce the distance between the two objective lenses 1 and improve the appearance of the entire device.

[0049] The imaging device 100 described so far can be made into a projection device such as a projector by replacing the imaging element 4 with a display element. Similarly, the imaging device 200 can be made into a projection device by replacing each of the two imaging elements 4 with a display element. The display element is, for example, a liquid crystal panel, LCOS (Liquid crystal on silicon), DMD (Digital Micromirror Device), or the like.

[0050] When the imaging device 100 and the imaging device 200 are each changed to a projection device, the objective lens 1 becomes a projection lens that projects an image displayed on a display element onto a projection object. The objective lens 1 becomes the optical element closest to a projection object such as a spherical screen. The light ray 1R becomes a light ray projected from the outermost edge of the range of the effective diameter of the objective lens 1. In this way, even in a projection device, by adopting the configuration of the optical element 2, it becomes possible to reduce the size and prevent vignetting of the light ray 1R.

[0051] Although the objective lens 1 in the imaging device or projection device described so far is a lens with a total angle of view exceeding 180 degrees, it is possible to obtain the effect of miniaturization even if the total angle of view is a lens of 180 degrees or less.

[0052] As described above, this specification includes at least the following:

[0053] (1) An optical system arranged on the opposite side to the object side with respect to an objective lens, A rotating member that is rotatably supported; a plurality of light transmission regions having different light transmission characteristics, the light transmission regions being formed on the rotating member and being arranged so as to be able to intersect with an optical axis of the objective lens; The rotation axis of the rotation member is configured to be non-parallel to the optical axis of the objective lens. optical system.

[0054] (2) The optical system according to (1), At least one set of the plurality of light transmitting regions is provided inclined in the same direction with respect to a plane perpendicular to the rotation axis. optical system.

[0055] (3) The optical system according to (2), The same direction is a direction away from the objective lens. optical system.

[0056] (4) The optical system according to any one of (1) to (3), The objective lens has a total angle of view of more than 180 degrees. optical system.

[0057] (5) The optical system according to (4), the rotating member is shaped to prevent a light beam incident on the outermost edge of the effective diameter range of the objective lens or a light beam projected from the outermost edge of the effective diameter range of the objective lens from being blocked by at least one of the light transmitting region and the rotating member. optical system.

[0058] (6) An optical system according to any one of (1) to (5), The rotating member is non-flat. optical system.

[0059] (7) The optical system according to (6), the rotating member has an annular portion in which the plurality of light transmitting regions are arranged in a circumferential direction, and a shaft portion formed inside the annular portion and on which the rotating shaft is formed, the annular portion is arranged such that a position of an inner peripheral edge portion in the rotation axis direction in a state where the rotation axis extends is located closer to the objective lens than a position of an outer peripheral edge portion in the rotation axis direction in a state where the rotation axis extends. optical system.

[0060] (8) The optical system according to (7), wherein the objective lens is a lens having an overall angle of view exceeding 180 degrees, wherein the plurality of light transmission regions are formed side by side at equal intervals in the annular portion, wherein two directions perpendicular to the optical axis and perpendicular to each other are defined as a first direction and a second direction, a state in which one of the light transmission regions intersects the optical axis perpendicularly is defined as an observation state when viewed from the first direction, in the observation state, a distance between an edge on the optical system side of a light passage range on the object side surface of the objective lens and an edge on the objective lens side of the light transmission region intersecting the optical axis is defined as L, an effective diameter of the objective lens is defined as D1, a length in the second direction of the light transmission region intersecting the optical axis is defined as d2, a value obtained by doubling a distance between an edge on the rotation axis side and the objective lens side of the light transmission region intersecting the optical axis and the rotation axis is defined as d3, an angle formed by the optical axis and the rotation axis is defined as θ, a half of the overall angle of view of the objective lens is defined as α, |{d2 / 2 + d3*cos(θ) + d2*cos(2θ) - D1 / 2}*cos(α)| is defined as L1, when |L + d3*sin(θ) + d2*sin(2θ)| is defined as L2, a relationship L1 < L2 holds, an optical system.

[0061] (9) An optical system according to any one of (1) to (8), wherein the rotation axis is in a twisted relationship with the optical axis, an optical system.

[0062] (10) An optical system according to any one of (1) to (9), and the objective lens, comprising a lens device.

[0063] (11) A first lens device which is the lens device according to (10); (10) and a second lens device arranged in parallel with the first lens device. Lens device.

[0064] (12) The lens device according to (11), the first lens device and the second lens device are arranged side by side in a state in which the optical system is in an axisymmetric relationship; Lens device.

[0065] (13) The lens device according to (12), the rotation axis of each of the first lens device and the second lens device is disposed outside the optical axis of each of the first lens device and the second lens device. Lens device.

[0066] (14) A lens device according to (10), an image sensor that captures an image of a subject through the lens device; Imaging device.

[0067] (15) A lens device according to any one of (11) to (13), an image sensor configured to capture an image of a subject through the first lens device and the second lens device; Imaging device.

[0068] (16) A lens device according to (10), A display element, projecting an image displayed by the display element through the lens device; Projection device.

[0069] (17) A lens device according to any one of (11) to (13), A display element, projecting an image displayed by the display device through the first lens device and the second lens device; Projection device. [Explanation of symbols]

[0070] 1J optical axis 1R ray 1e,22Ae,22Be,22Beo Edge 1 Objective lens 2. Optical elements 3. Lens device 4. Image sensor 5. Control section 6 Drive unit 7. Cabinet 21A Circular section 21B Shaft 21J Rotating shaft 21Aei Inner edge 21Bk,21k opening 21Aeo Outer edge 21 Rotating member 22A, 22B, 22C, 22D Filters 23 Shaft member 100A, 100B, 100, 200 Imaging device P intersection

Claims

1. An optical system arranged on the opposite side to the object side with respect to an objective lens, A rotating member that is rotatably supported; a plurality of light transmission regions having different light transmission characteristics, the light transmission regions being formed on the rotating member and being arranged so as to be able to intersect with an optical axis of the objective lens; The rotation axis of the rotation member is configured to be non-parallel to the optical axis of the objective lens, The objective lens is a lens having a total angle of view exceeding 180 degrees, the rotating member is shaped to prevent a light beam incident on the outermost edge of the effective diameter range of the objective lens or a light beam projected from the outermost edge of the effective diameter range of the objective lens from being blocked by at least one of the light transmitting region and the rotating member. optical system.

2. 2. The optical system according to claim 1, At least one set of the plurality of light transmitting regions is provided inclined in the same direction with respect to a plane perpendicular to the rotation axis. optical system.

3. 3. The optical system according to claim 2, The same direction is a direction away from the objective lens. optical system.

4. 4. The optical system according to claim 1 , The rotating member is non-flat. optical system.

5. 5. The optical system according to claim 4, the rotating member has an annular portion in which the plurality of light transmitting regions are arranged in a circumferential direction, and a shaft portion formed inside the annular portion and on the inside of which the rotating shaft is formed, the annular portion is disposed such that a position of an inner peripheral edge portion in a rotation axis direction in which the rotation axis extends is located closer to the objective lens than a position of an outer peripheral edge portion in the rotation axis direction in a state where the annular portion is viewed in the rotation axis direction. optical system.

6. 6. The optical system according to claim 5, The objective lens is a lens having a total angle of view exceeding 180 degrees, The plurality of light transmitting regions are formed in the annular portion at equal intervals, Two directions perpendicular to the optical axis and perpendicular to each other are defined as a first direction and a second direction, A state in which one of the light transmitting regions perpendicularly intersects with the optical axis is viewed from the first direction as an observation state; In the observation state, L is a distance between an edge of a light passing range on the object side surface of the objective lens on the optical system side and an edge of the light transmitting region on the objective lens side that intersects with the optical axis, The effective diameter of the objective lens is D1, The length of the light transmitting region intersecting the optical axis in the second direction is d2, d3 is twice the distance between the edge of the light transmitting region that is on the rotation axis side and the objective lens side and that intersects with the optical axis, and the rotation axis; The angle between the optical axis and the rotation axis is θ, α is 1 / 2 of the total angle of view of the objective lens, Let |{d2 / 2+d3*cos(θ)+d2*cos(2θ)-D1 / 2}*cos(α)| be L1, When |L+d3*sin(θ)+d2*sin(2θ)| is L2, The relationship L1 < L2 holds. optical system.

7. 7. The optical system according to claim 1 , The rotation axis is in a twisted relationship with the optical axis. optical system.

8. An optical system according to any one of claims 1 to 7; The objective lens, Lens device.

9. A first lens arrangement, which is the lens arrangement according to claim 8; a second lens arrangement, the second lens arrangement being as claimed in claim 8 and juxtaposed with the first lens arrangement; Lens device.

10. 10. The lens device according to claim 9, the first lens device and the second lens device are arranged side by side in a state in which the optical system is in an axisymmetric relationship; Lens device.

11. 11. The lens device according to claim 10, the rotation axis of each of the first lens device and the second lens device is disposed outside the optical axis of each of the first lens device and the second lens device. Lens device.

12. A lens device according to claim 8; an image sensor that captures an image of a subject through the lens device; Imaging device.

13. A lens device according to any one of claims 9 to 11; an image sensor configured to capture an image of a subject through the first lens device and the second lens device; Imaging device.

14. A lens device according to claim 8; A display element, projecting an image displayed by the display element through the lens device; Projection device.

15. A lens device according to any one of claims 9 to 11; A display element, projecting an image displayed by the display device through the first lens arrangement and the second lens arrangement; Projection device.

Images