Optical member, lens device, and imaging device

Abstract

Provided are an optical member having a plurality of opening regions, a lens device, and an imaging device. The lens device (100) includes: an imaging optical system (100A); a first polarization unit (101) that polarizes at least a portion of light that passes through the imaging optical system (100A); and a filter unit (130) that is disposed closer to an image side than the first polarization unit (101) and is disposed at or near a pupil position of the imaging optical system, the filter unit (130) including: a plurality of opening regions that allow light of the imaging optical system (100A) to pass therethrough and including a first opening region and a second opening region; a plurality of wavelength selection filters that are disposed in the first opening region and the second opening region and allow at least a portion of light of different wavelength bands to pass therethrough, respectively; and a second polarization filter that is disposed in the first opening region and the second opening region and has a plurality of polarization filters having different polarization directions from each other.

Description

Technical Field

[0001] This invention relates to an optical component, a lens device, and a camera device, and more particularly to an optical component, a lens device, and a camera device having multiple opening regions. Background Technology

[0002] There is a known technique for simultaneously acquiring multiple images with distinct image information.

[0003] Patent Document 1 describes a technique for simultaneously acquiring multiple images with different optical conditions. In the technique described in Patent Document 1, crosstalk correction processing is performed to reduce the effects of crosstalk caused by array-shaped optical elements such as microlens arrays or biconvex lenses.

[0004] Previous technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2015-211430 Summary of the Invention

[0007] One embodiment of the present invention provides an optical component, a lens device, and a camera device having multiple opening regions.

[0008] means for solving technical problems

[0009] A lens device according to one aspect of the present invention includes: a camera optical system; a first polarizing section that polarizes at least a portion of light transmitted through the camera optical system; and a filter unit disposed further on the image side than the first polarizing section and disposed at or near the pupil position of the camera optical system, the filter unit comprising: a plurality of opening regions that allow light from the camera optical system to pass through, including the first opening region and the second opening region; a plurality of wavelength selective filters disposed in the first opening region and the second opening region, allowing at least a portion of light with different wavelengths to pass through; and a second polarizing filter disposed in the first opening region and the second opening region, having a plurality of polarizing filters with different polarization directions.

[0010] Preferably, the polarization direction of the first polarization section is variable.

[0011] Preferably, the first polarizing section is a first polarizing filter that rotates around the optical axis.

[0012] Preferably, the first polarizing part is disposed on the object side of the lens included in the imaging optical system.

[0013] Preferably, the first polarizing part is disposed within the camera optical system and is disposed closer to the object side than the filter unit.

[0014] Preferably, the first polarization section has multiple regions with different polarization directions.

[0015] Preferably, the first polarization section has multiple regions that can independently change the polarization direction, and the multiple regions rotate along their respective rotation axes.

[0016] Preferably, the second polarizing filter is disposed on the image side of multiple wavelength selective filters.

[0017] The preferred filter unit further includes multiple optical path length correction filters, which are disposed in the first opening region and the second opening region to correct on-axis chromatic aberration caused by multiple wavelength selective filters.

[0018] The preferred filter unit further includes an ND filter, which is disposed in the first opening region and the second opening region to reduce the amount of light from the camera optical system.

[0019] Preferably, the first polarization section is composed of a polarization filter and a liquid crystal polarization rotation element disposed on the image side of the polarization filter.

[0020] The preferred lens device includes a polarization direction control unit, which controls the polarization direction of the first polarization part. The polarization direction control unit controls the polarization direction of the first polarization part based on the ratio of the amount of light corresponding to the first opening region to the amount of light corresponding to the second opening region.

[0021] The preferred lens device includes a polarization direction limiting section, which limits the polarization direction of the first polarization section to a predetermined position. The polarization direction limiting section limits the polarization direction of the first polarization section according to the ratio of the amount of light corresponding to the first opening region to the amount of light corresponding to the second opening region.

[0022] As another aspect of the present invention, an optical component is disposed at or near the pupil position of a camera optical system, and includes: a first polarizing filter that polarizes at least a portion of the light transmitted through the camera optical system; and a plurality of opening regions that allow light from the camera optical system to pass through, including the first opening region and the second opening region. The optical component further includes: a plurality of wavelength selective filters disposed in the first and second opening regions, allowing at least a portion of light with different wavelengths to pass through; and a second polarizing filter disposed in the first and second opening regions, having a plurality of polarizing filters with different polarization directions. The first polarizing filter is disposed closest to the object side, and the second polarizing filter is disposed closest to the image side.

[0023] As another aspect of the present invention, the camera device includes the above-described lens device or the above-described optical component.

[0024] As another aspect of the present invention, an optical component is disposed at or near the pupil position of a camera optical system, having multiple opening regions through which light from the camera optical system can pass, including a first opening region and a second opening region. The optical component comprises: an ND filter disposed in the first and second opening regions to reduce the amount of light from the camera optical system; multiple wavelength selective filters disposed in the first and second opening regions, allowing light of at least a portion of different wavelength bands to pass through; multiple optical path length correction filters disposed in the first and second opening regions to correct on-axis chromatic aberration caused by the multiple wavelength selective filters; and multiple polarization filters disposed in the first and second opening regions with different polarization directions, wherein the optical path length correction filters are disposed closer to the image side than the wavelength selective filters.

[0025] As another aspect of the present invention, the camera device includes the above-described optical components and a polarization section that polarizes at least a portion of the light transmitted through the camera optical system. Attached Figure Description

[0026] Figure 1 It is a diagram showing the general structure of a camera device.

[0027] Figure 2 This is a diagram showing the structure of the signal processing unit and the lighting device.

[0028] Figure 3 It is a diagram showing the general structure of the imaging element.

[0029] Figure 4 It means Figure 3 A cross-sectional view of a 1-pixel schematic structure is shown.

[0030] Figure 5 This is a three-dimensional view of the lens assembly.

[0031] Figure 6 This is a cross-sectional view of the lens device on the yz plane.

[0032] Figure 7 This is an external view of the frame.

[0033] Figure 8 This is a diagram illustrating an example of the structure of a wavelength polarizing filter unit.

[0034] Figure 9 This is a diagram illustrating an example of the structure of a filter assembly.

[0035] Figure 10 It is a diagram showing the relationship between the opening area and the filter structure.

[0036] Figure 11This is a diagram showing the frame and filter assembly.

[0037] Figure 12 This is a conceptual diagram representing the first polarizing filter and lens assembly.

[0038] Figure 13 This is a table explaining how to adjust the amount of light.

[0039] Figure 14 This is a table explaining how to adjust the amount of light.

[0040] Figure 15 This is a table explaining how to adjust the amount of light.

[0041] Figure 16 This is a conceptual diagram representing the first polarizing filter and lens assembly.

[0042] Figure 17 This is a table explaining how to adjust the amount of light.

[0043] Figure 18 This is a table explaining how to adjust the amount of light.

[0044] Figure 19 This is a table explaining how to adjust the amount of light.

[0045] Figure 20 This is a conceptual representation of the first polarizing filter.

[0046] Figure 21 This is a table explaining how to adjust the amount of light.

[0047] Figure 22 This is a diagram illustrating another example of the first polarization section.

[0048] Figure 23 This is a diagram illustrating another example of the first polarization section.

[0049] Figure 24 This is a conceptual representation of the first polarizing filter and the wavelength polarizing filter unit.

[0050] Figure 25 This is a conceptual representation of the first polarizing filter and the wavelength polarizing filter unit.

[0051] Figure 26 This is a diagram illustrating the configuration of the second polarizing filter.

[0052] Figure 27 This is a diagram illustrating the configuration of the second polarizing filter.

[0053] Figure 28 This diagram illustrates the configuration of the wavelength-selective filter and the second polarizing filter.

[0054] Figure 29This diagram illustrates the configuration of the wavelength-selective filter and the second polarizing filter.

[0055] Figure 30 This diagram illustrates the configuration of ND filters and wavelength selective filters.

[0056] Figure 31 This is a diagram illustrating the configuration of ND filters.

[0057] Figure 32 This is a diagram illustrating the configuration of ND filters.

[0058] Figure 33 This is a diagram illustrating the configuration of the optical path length correction filter.

[0059] Figure 34 This is a diagram illustrating the configuration of the optical path length correction filter. Detailed Implementation

[0060] Hereinafter, preferred embodiments of the optical components, lens devices, and imaging devices involved in the present invention will be described with reference to the accompanying drawings.

[0061] Figure 1 This diagram shows a schematic structure of the imaging device 10. The imaging device 10 is a multispectral camera that captures multispectral images. The imaging device 10 includes a lens assembly 100, an imaging device main body 200, and an illumination device 100B. The imaging device main body 200 includes an imaging element 210 and a signal processing unit 230. The lens assembly 100 includes a first polarizing filter 101 (first polarizing section) disposed on the object side, an imaging optical system 100A composed of a first lens 110 and a second lens 120, and a wavelength polarizing filter unit (filter unit, optical component) 130 disposed at or near the pupil position of the imaging optical system 100A. Furthermore, the imaging device 10 includes an illumination device 100B. The imaging device 10 acquires a multispectral image of the subject illuminated by the illumination device 100B. In the following description, the object side refers to the positive side of the z-axis shown in the diagram, and the image side refers to the negative side of the z-axis.

[0062] Figure 2This diagram illustrates the structure of the signal processing unit 230 and the illumination device 100B. The signal processing unit 230 includes an analog signal processing unit 232 that performs analog signal processing on the signal output from the imaging element 210, an image generation unit 234, and a coefficient storage unit 236. The image generation unit 234 (processor) includes a non-temporary recording medium (not shown) such as a ROM (Read Only Memory) containing computer-readable code that enables a computer to execute an imaging program, and a temporary storage area (not shown) for operation. Based on the multiple image signals output from the imaging element 210, it generates multiple images (spectral images) corresponding to the bands of the multiple wavelength selective filters disposed in the imaging optical system 100A. For example, the image generation unit 234 can generate images (three-band multispectral images) corresponding to the bands λ1, λ2, and λ3 of the wavelength selective filters.

[0063] The functions of the aforementioned signal processing unit 230 are implemented using various processors and recording media. These processors include, for example, general-purpose processors that execute software (programs) to implement various functions, such as CPUs (Central Processing Units); GPUs (Graphics Processing Units) that specialize in image processing; and FPGAs (Field Programmable Gate Arrays), which are processors whose circuit structure can be changed after manufacturing—that is, programmable logic devices (PLDs). Each function can be implemented by a single processor, or by multiple processors of the same or different types (e.g., multiple FPGAs, a combination of CPUs and FPGAs, or a combination of CPUs and GPUs). Furthermore, multiple functions can be implemented by a single processor. More specifically, the hardware structure of these various processors is a circuit composed of circuit elements such as semiconductor components.

[0064] When the aforementioned processor or circuit executes the software (program), the code that can be read by the computer executing the software (e.g., various processors or circuits constituting the image generation unit 234 and / or combinations thereof) is stored in a non-temporary recording medium such as ROM, and the computer refers to the software.

[0065] When the imaging device 10 receives a photography instruction input, such as from a shutter release switch (not shown), it performs exposure control in the imaging element 210. The optical image of the subject, imaged on the light-receiving surface of the imaging element 210 by this exposure control, is converted into an electrical signal by the imaging element 210. This signal is then stored in each pixel of the imaging element 210 and incident on the photodiode 212. Figure 3 The amount of light corresponding to the charge is read from the imaging element 210 and the electrical signal corresponding to the amount of charge stored in each pixel is used as an image signal and output.

[0066] The lighting device 100B includes: a light source 320 that illuminates the subject with illumination light having spectral characteristics (bands, etc.) including multiple wavelength selective filters disposed in the imaging optical system 100A; and a light source control unit 310 that controls the illumination of the light source 320. The light source 320 of the lighting device 100B can be any type of light source 320. For example, the light source 320 can be a halogen lamp or an LED (light emitting diode).

[0067] Figure 3 This is a diagram showing a schematic structure of the imaging element 210. Figure 4 It means Figure 3 The diagram shows a cross-sectional view of a schematic structure for one pixel. Imaging element 210 is a CMOS (Complementary Metal-Oxide Semiconductor) type imaging element (image sensor), a monochrome imaging element having a pixel array layer 211, a polarizing filter element array layer 213, and a microlens array layer 215. The pixel array layer 211, the polarizing filter element array layer 213 (multiple polarizing elements), and the microlens array layer 215 are arranged sequentially from the image (plane) side towards the object side. Furthermore, imaging element 210 is not limited to CMOS type; it can also be an XY address type or a CCD (Charge Coupled Device) type image sensor.

[0068] The pixel array layer 211 is composed of multiple photodiodes 212 (multiple pixel groups) arranged in a two-dimensional pattern. One photodiode 212 constitutes one pixel. The photodiodes 212 are regularly arranged along the horizontal direction (x-direction) and the vertical direction (y-direction).

[0069] The polarizing filter element array layer 213 is constructed by arranging four types of polarizing filter elements (polarizers) 214A, 214B, 214C, and 214D (multiple polarizing elements) with different polarization directions (polarization directions of transmitted light) in a two-dimensional arrangement. The polarization directions of the polarizing filter elements 214A, 214B, 214C, and 214D can be set to, for example, 0°, 45°, 90°, and 135°. Furthermore, as another example, the polarization directions of the polarizing filter elements 214A, 214B, 214C, and 214D can be set to 0°, 60°, 90°, and 120°. Moreover, these polarization directions can be correlated with the second polarizing filters 148A to 148C (reference) in the wavelength polarizing filter unit 130. Figure 8 The polarization direction corresponds to that of the photodiode 212. The imaging element 210 includes a plurality of pixels, which selectively receive any one of the light transmitted through the plurality of opening regions via polarization filter elements 214A to 214D. These polarization filter elements 214A to 214D are arranged at the same interval as the photodiode 212, and are set per pixel.

[0070] The microlens array layer 215 has microlenses 216 arranged in each pixel.

[0071] Figure 5 This is a perspective view of the lens device 100. Figure 6 These are cross-sectional views of the lens assembly 100 in the yz plane. As shown in these figures, the lens assembly 100 houses a single imaging optical system 100A composed of a first lens 110 and a second lens 120 within the lens barrel 102. The first lens 110 and the second lens 120 may also be a lens group composed of multiple lenses. Furthermore, a slit 108 is formed in the lens barrel 102 at the pupil position (near the pupil) of the lens assembly 100, and a wavelength polarizing filter unit 130 is inserted into this slit 108, configured so that its optical axis is aligned with the optical axis L of the imaging optical system 100A.

[0072] Figure 7 This is an external view of frame 132. Figure 8 This is a diagram showing an example of the structure of the wavelength polarizing filter unit 130. Figure 7 Parts (a) to (f) are respectively the rear view, top view, left side view, bottom view, perspective view, and front view. For example... Figure 7 As shown in parts (a), (e), and (f), the frame 132 has four opening regions 132A to 132D. Furthermore, opening regions 132A to 132D correspond to the first to fourth opening regions. The shape of opening regions 132A to 132D is not limited to a fan shape; it can also be circular, elongated, rectangular, polygonal, or other shapes. When acquiring three images (images of bands λ1, λ2, and λ3), since three opening regions are sufficient, opening region 132D is as follows... Figure 8 As shown, the light is blocked by the shielding member B. Furthermore, in this example, by shielding the opening region 132D with the shielding member B, the opening regions 132A to 132C are made effective, but this is not a limitation. For example, it is also possible to not have the shielding member B and instead arrange a wavelength selective filter of the same band as any of the opening regions 132A to 132C and a second polarizing filter with the same polarization direction in the opening region 132D.

[0073] Furthermore, in the three unshaded opening areas (132A~132C), such as Figure 8As shown, filter groups 1.40A to 140C are respectively configured with ND (Neutral Density) filters, wavelength selective filters, optical path length correction filters, and a second polarizing filter. Additionally, in Figure 8 The diagram shows filter groups 140A to 140C, each consisting of four filters. Furthermore, in each of filter groups 140A to 140C, the filter closest to the object side (ND filter) is positioned on the object-side surface of the frame 132, while the remaining three (wavelength selection filter, optical path length correction filter, and second polarizing filter) are positioned on the image-side surface of the frame 132. However, the arrangement of the filters and the position of the frame 132 between the filters are not limited to the example described above, and various methods can be employed.

[0074] Figure 9 This is a diagram illustrating the structural examples of filter groups 140A to 140C.

[0075] Filter group 140A consists of four different types of filters. From the object side, filter group 140A consists of an ND filter 142A, a wavelength-selective filter 144A that allows light of wavelength band λ1 to pass through, an optical path length correction filter 146A, and a second polarizing filter 148A with a polarization direction of 0°. Similarly, from the object side, filter group 140B consists of an ND filter 142B, a wavelength-selective filter 144B that allows light of wavelength band λ2 to pass through, an optical path length correction filter 146B, and a second polarizing filter 148B with a polarization direction of 60°. Similarly, from the object side, filter group 140C consists of an ND filter 142C, a wavelength-selective filter 144C that allows light of wavelength band λ3 to pass through, an optical path length correction filter 146C, and a second polarizing filter 148C with a polarization direction of 120°. Furthermore, in this example, since spectral images of band λ1, band λ2, and band λ3 are acquired, the polarization directions of the second polarizing filters 148A to 148C are different. For example, when acquiring two spectral images, at least two second polarizing filters with different polarization directions are used. Also, a portion of the bands of λ1, λ2, and λ3 are different. Furthermore, the ND filters 142A to 142C have the function of reducing the amount of light, and the optical path length correction filters 146A to 146C have the function of correcting axial chromatic aberration. In this embodiment, polarization directions of 0°, 60°, and 120° are used, but combinations of other angles are also possible.

[0076] Figure 10 It is a diagram showing the relationship between the opening area and the filter structure.

[0077] The wavelength polarization filter unit 130 has opening regions 132A to 132D formed by a frame 132. Specifically, region boundary members 132(a) of the frame 132 are disposed at the boundaries of opening regions 132A and 132D, and opening regions 132B and 132C, and region boundary members 132(β) are disposed at the boundaries of opening regions 132A and 132B, and opening regions 132C and 132D. Furthermore, ND filters 142A to 142C, wavelength selective filters 144A to 144C, optical path length correction filters 146A to 146C, and second polarization filters 148A to 148C are respectively disposed in opening regions 132A to 132C.

[0078] Figure 11 This is a diagram showing the frame 132 and the filter groups 140A to 140C. Figure 11 (A) is a diagram showing the opening regions 132A to 132D formed by the frame 132. Figure 11 (B) is a cross-sectional view showing the filter groups 140B and 140C disposed in the opening regions 132B and 132C.

[0079] An ND filter 142B, a wavelength selective filter 144B, an optical path length correction filter 146B, and a second polarizing filter 148B are provided in the opening region 132B. Furthermore, an ND filter 142C, a wavelength selective filter 144C, an optical path length correction filter 146C, and a second polarizing filter 148C are provided in the opening region 132C.

[0080] <Optical Amount Adjustment Based on Polarizing Filters>

[0081] As described above, the imaging device 10 of the present invention includes a first polarizing filter 101 and second polarizing filters 148A to 148C. The imaging device 10 can adjust the amount of light in the opening regions 132A to 132C according to the difference in polarization direction between the first polarizing filter 101 and the second polarizing filters 148A to 148C.

[0082] Hereinafter, the first to fourth embodiments related to the adjustment of light intensity in the opening regions 132A to 132C of the imaging device 10 will be described.

[0083] <First Implementation>

[0084] First, the first embodiment will be described. In this embodiment, the first polarization section is composed of a first polarization filter 101, and the amount of light in the opening regions 132A to 132C is adjusted by rotating the first polarization filter 101.

[0085] Figure 12This diagram conceptually illustrates the first polarizing filter 101 and lens assembly 100 of this embodiment. The frame 132 of the wavelength polarizing filter unit 130 is omitted from the diagram. Furthermore, the ND filters 142A-142C, wavelength selective filters 144A-144C, and optical path length correction filters 146A-146C are shown as an integrated intermediate filter A.

[0086] The first polarizing filter 101 allows light with a polarization direction in one direction to pass through. The first polarizing filter 101 functions as a first polarizing unit, polarizing at least a portion of the light passing through the imaging optical system 100A. The first polarizing filter 101 can change the polarization direction of the transmitted light by rotating about the optical axis L. The polarization direction is also 0° when the rotation angle θ of the first polarizing filter 101 is 0°, and the first polarizing filter 101 is configured such that the polarization direction can be changed in accordance with the rotation angle θ. Furthermore, the polarization direction of 0° refers to the direction along the y-axis. And, when viewing the first polarizing filter 101 from the object side to the image side, the clockwise direction is taken as a positive rotation angle, and the counterclockwise direction is taken as a negative rotation angle.

[0087] The amount of light (or the change in light amount) in the opening regions 132A to 132C can be calculated using the rotation angle θ of the first polarizing filter 101.

[0088] Specifically, the light intensity variation α of the opening regions 132A to 132C is calculated using the following formula (1). i In addition, the change in light intensity in the opening region 132A is represented by the change in light intensity α0, the change in light intensity in the opening region 132B is represented by the change in light intensity α1, and the change in light intensity in the opening region 132C is represented by the change in light intensity α2.

[0089] [Formula 1]

[0090] Light change α i =cos 2 (θ-Φ i (1)

[0091] Furthermore, θ in equation (1) represents the polarization direction (or rotation angle) of the first polarizing filter 101. And, in equation (1), Φ... i In the diagram, Φ0 represents the angle of polarization direction of the second polarizing filter in the opening region 132A, Φ1 represents the angle of polarization direction of the second polarizing filter in the opening region 132B, and Φ2 represents the angle of polarization direction of the second polarizing filter in the opening region 132C.

[0092] As explained above, the amount of light in the opening regions 132A to 132C can be adjusted using the first polarizing filter 101 and the second polarizing filters 148A to 148C.

[0093] The following describes an embodiment of adjusting the light intensity in the opening regions 132A to 132C.

[0094] (First Embodiment)

[0095] Figure 13 Table 501 is a table illustrating the light intensity adjustment of the first embodiment. Furthermore, in this example, the ND filter 142 is not used. Also, the wavelength selective filter 144A disposed in the aperture region 132A selectively transmits light in the blue band (referred to as "B" in the table), the wavelength selective filter 144B disposed in the aperture region 132B selectively transmits light in the green band (referred to as "G" in the table), and the wavelength selective filter 144C disposed in the aperture region 132C selectively transmits light in the red band. Furthermore, in this example and the examples described below, the polarization direction of the second polarizing filter 148A disposed in the aperture region 132A is 0°, the polarization direction of the second polarizing filter 148B disposed in the aperture region 132B is 60°, and the polarization direction of the second polarizing filter 148C disposed in the aperture region 132C is 120°.

[0096] When the light source 320 is a halogen lamp, by rotating the first polarizing filter 101 4° clockwise, the light intensity ratio in the opening regions 132A to 132C is close to 1:1:1, which can make the light intensity of each opening region well balanced. Hereinafter, Table 501 will be used for explanation.

[0097] When the light source 320 is set to a halogen lamp, without the first polarizing filter 101 (initial state), a light quantity of 40 is obtained in the opening region 132A (“B”), a light quantity of 100 is obtained in the opening region 132B (“G”), and a light quantity of 140 is obtained in the opening region 132C (“R”) (Item (1) of Table 501). The change in light quantity in each opening region 132A to 132C when the first polarizing filter 101 is rotated 4° clockwise is calculated by the above formula (1) (Item (2) of Table 501). Furthermore, by calculating the product of the light quantity in the initial state when the light source 320 is set to a halogen lamp and the calculated change in light quantity, the light quantity in the opening regions 132A to 132C when the first polarizing filter 101 is rotated 4° clockwise is calculated (Item (3) of Table 501). These light intensity ratios are 1.27297∶1∶0.860377 (item (4)) in Table 501. By rotating the first polarizing filter 101 4° clockwise, the light intensity of the opening regions 132A to 132C can be well balanced.

[0098] When the light source 320 is set as an LED, by rotating the first polarizing filter 101 counterclockwise by 63°, the light intensity ratio in the opening regions 132A to 132C is close to 1:1:1, which can make the light intensity of each opening region well balanced. Hereinafter, Table 501 will be used for explanation.

[0099] When the light source 320 is set as an LED, without the first polarizing filter 101 (initial state), a light quantity of 140 is obtained in the opening region 132A (“B”), a light quantity of 100 is obtained in the opening region 132B (“G”), and a light quantity of 30 is obtained in the opening region 132C (“R”) (item (5) of Table 501). The change in light quantity in each opening region 132A to 132C when the first polarizing filter 101 is rotated 63° counterclockwise is calculated by the above formula (1) (item (6) of Table 501). Furthermore, by calculating the product of the light quantity in the initial state when the light source 320 is set as an LED and the calculated change in light quantity, the light quantity in the opening regions 132A to 132C when the first polarizing filter 101 is rotated 63° counterclockwise is calculated (item (7) of Table 501). These light intensity ratios are 0.972756∶1∶1.008585 (item (8)) in Table 501. By rotating the first polarizing filter 101 counterclockwise by 63°, the light intensity of the opening regions 132A to 132C can be well balanced.

[0100] As explained above, by rotating the first polarizing filter 101 by a predetermined angle, even when the light source 320 is a halogen lamp or an LED, the light intensity ratio of the opening regions 132A to 132C can be made close to 1:1:1, thereby ensuring a good balance of light intensity in each opening region.

[0101] (Second Embodiment)

[0102] Next, the second embodiment will be described. Figure 14 Table 503 is a table illustrating the light intensity adjustment in the second embodiment. In this embodiment, the light source 320 is changed from a halogen lamp to an LED. Furthermore, ND filters 142A to 142C are set when the light source 320 is a halogen lamp and the rotation angle θ of the first polarizing filter 101 is 0°. Other settings are the same as in the first embodiment.

[0103] When the light source 320 changes from a halogen lamp to an LED, by rotating the first polarizing filter 101 clockwise by 121°, the light intensity ratio of the opening regions 132A to 132C can be made close to 1:1:1, thereby ensuring a good balance of light intensity in each opening region. Table 503 will be used for explanation below.

[0104] In the initial state (without the first polarizing filter 101 and without ND filters 142A to 142C) when the light source 320 is an LED or a halogen lamp, the same amount of light is obtained in the opening regions 132A to 132C as in the first embodiment (items (1) and (2) of Table 503). When the rotation angle of the first polarizing filter 101 is 0°, the change in the amount of light in each opening region 132A to 132C is calculated by the above formula (1) (item (3) of Table 503). The change in the amount of light in the ND filters 142A to 142C is set according to the case where the light source 320 is a halogen lamp (item (4) of Table 503). That is, the light intensity in the open area 132A (“B”) is 40×1×0.625=25, the light intensity in the open area 132B (“G”) is 100×0.25×1=25, and the light intensity in the open area 132C (“R”) is 140×0.25×0.714286≈25 (the product of items (2), (3), and (4) in Table 503). Thus, when the light source 320 is a halogen lamp, the light intensity in the open areas 132A~132C is well balanced.

[0105] On the other hand, when the light source 320 is changed from a halogen lamp to an LED, the light balance mentioned above is disrupted because the ND filters 142A to 142C are set to be used for halogen lamps (item (5) of Table 503).

[0106] Therefore, the light intensity is changed by rotating the first polarizing filter 101 clockwise by 121° (item (6) in Table 503). Thus, by rotating the first polarizing filter 101 clockwise by 121°, the light intensity of the aperture regions 132A to 132C changes (item (7) in Table 503). Furthermore, the light intensity ratio of the aperture regions 132A to 132C becomes 0.987516∶1∶0.91142 (item (8) in Table 503), and even when the light source 320 is changed to an LED, the disruption of the light intensity balance can be suppressed.

[0107] As explained above, when the ND filters 142A to 142C are set for halogen lamps, when the light source 320 is changed from a halogen lamp to an LED, the first polarizing filter 101 is rotated to change the polarization direction, thereby adjusting the light amount in the aperture regions 132A to 132C. This prevents the light amount balance in the aperture regions 132A to 132C from being disrupted.

[0108] (Third Embodiment)

[0109] Next, the third embodiment will be described. Figure 15Table 505 describes the light intensity adjustment in the third embodiment. In this embodiment, the light source 320 is changed from an LED to a halogen lamp. Furthermore, ND filters 142A to 142C are set when the light source 320 is an LED and the rotation angle θ of the first polarizing filter 101 is 120°. Other settings are the same as in the first embodiment.

[0110] When the light source 320 is changed from an LED to a halogen lamp, by rotating the first polarizing filter 101 clockwise by 1°, the light intensity ratio of the opening regions 132A to 132C can be made close to 1:1:1, thus suppressing the disruption of the light intensity balance in each opening region. The following explanation uses Table 505.

[0111] In the initial state (without the first polarizing filter 101 and without ND filters 142A to 142C) when the light source 320 is an LED or a halogen lamp, the same amount of light is obtained in the opening regions 132A to 132C as in the first embodiment (items (1) and (2) of Table 505). When the rotation angle of the first polarizing filter 101 is 120°, the change in the amount of light in each opening region 132A to 132C is calculated by the above formula (1) (item (3) of Table 505). The change in the amount of light in the ND filters 142A to 142C is set according to the case where the light source 320 is an LED (item (4) of Table 505). That is, the light intensity in the opening region 132A (“B”) is 140×0.25×0.714286≈25, the light intensity in the opening region 132B (“G”) is 100×0.25×1=25, and the light intensity in the opening region 132C (“R”) is 30×1×0.833333≈25 (the product of items (2), (3), and (4) in Table 505). Thus, when the light source 320 is an LED, the light intensity in the opening regions 132A to 132C is well balanced.

[0112] On the other hand, when the light source 320 is changed from an LED to a halogen lamp, the above-mentioned light balance is disrupted because the ND filters 142A to 142C are set for LEDs (item (5) of Table 505).

[0113] Therefore, the light intensity is changed by rotating the first polarizing filter 101 clockwise by 1° (item (6) of Table 505). Thus, by rotating the first polarizing filter 101 clockwise by 1°, the light intensity of the aperture regions 132A to 132C changes (item (7) of Table 505). Furthermore, the light intensity ratio of the aperture regions 132A to 132C becomes 1.076765∶1∶1.033738 (item (8) of Table 505), and even when the light source 320 is changed to a halogen lamp, the disruption of the light intensity balance can be suppressed.

[0114] As explained above, when the ND filters 142A to 142C are set for LEDs, when the light source 320 is changed from an LED to a halogen lamp, the first polarizing filter 101 is rotated to change the polarization direction, thereby adjusting the light amount in the aperture regions 132A to 132C. This prevents the light amount balance in the aperture regions 132A to 132C from being disrupted.

[0115] <Second Implementation Method>

[0116] Next, the second embodiment will be described. In this embodiment, the first polarization section is composed of a first polarizing filter 101 having multiple regions with different polarization directions. Furthermore, the amount of light in the opening regions 132A to 132C is adjusted by rotating the first polarizing filter 101.

[0117] Figure 16 This diagram conceptually illustrates the first polarizing filter 101 and the lens device 100 of this embodiment. The illustration of the frame 132 of the wavelength polarizing filter unit 130 is omitted. Furthermore, the ND filters 142A-142C, wavelength selective filters 144A-144C, and optical path length correction filters 146A-146C are shown as an integrated intermediate filter A.

[0118] The first polarizing filter 101 has multiple regions with different polarization directions. Specifically, the first polarizing filter 101 has four regions 101A to 101D with different polarization directions. When the rotation angle θ is 0°, region 101A sets the polarization direction angle to 150°, region 101B sets the polarization direction angle to 172°, region 101C sets the polarization direction angle to 53°, and region 101D sets the polarization direction angle to 20°.

[0119] Light intensity variation α in the opening region 132A–132C i It can be calculated using the following equation (2). Furthermore, the change in light intensity in the opening region 132A is represented by the change in light intensity α0, the change in light intensity in the opening region 132B is represented by the change in light intensity α1, the change in light intensity in the opening region 132C is represented by the change in light intensity α2, and the change in light intensity in the opening region 132D is represented by the change in light intensity α3. Additionally, in the example of the imaging device 10 described above, the opening region 132D is blocked by the shielding member B.

[0120] [Formula 2]

[0121]

[0122] In addition, the following values ​​are represented in equation (2).

[0123] θ'=(θ+180)%90

[0124] [Formula 3]

[0125]

[0126]

[0127] In addition, the above uses the expression A%B to represent the remainder when A is divided by B.

[0128] The rotation angle of the first polarizing filter: θ

[0129] [Formula 4]

[0130] Polarization resolution of the opening region 132A: Φ0

[0131] Polarization angle of opening region 132B: Φ1

[0132] Polarization angle of opening region 132C: Φ2

[0133] Polarization angle of opening region 132D: Φ3

[0134] [Formula 5]

[0135] Polarization angle of region 101A: Ψ0

[0136] Polarization angle of region 101B: Ψ1

[0137] Polarization angle of region 101C: Ψ2

[0138] Polarization angle of region 101D: Ψ3

[0139] As explained above, the amount of light in the opening regions 132A to 132C can be adjusted using the first polarizing filter 101 and the second polarizing filters 148A to 148C.

[0140] The following describes an embodiment of adjusting the light intensity in the opening regions 132A to 132C.

[0141] (Example 4)

[0142] Figure 17 Table 507 is a table illustrating the light intensity adjustment of the fourth embodiment. Furthermore, in this example, the ND filter 142 is not used. Also, the wavelength selection filters 144A-144C and the second polarizing filters 148A-148C disposed in each aperture region are the same as in the first embodiment.

[0143] When the light source 320 is a halogen lamp, by rotating the first polarizing filter 101 counterclockwise by 10°, the light intensity ratio in the opening regions 132A to 132C is close to 1:1:1, which can make the light intensity of each opening region well balanced. Hereinafter, Table 507 will be used for explanation.

[0144] When the light source 320 is set to a halogen lamp, without the first polarizing filter 101 (initial state), a light quantity of 40 is obtained in the opening region 132A (“B”), a light quantity of 100 is obtained in the opening region 132B (“G”), and a light quantity of 140 is obtained in the opening region 132C (“R”) (Item (1) of Table 507). The change in light quantity in each opening region 132A to 132C when the first polarizing filter 101 is rotated 10° counterclockwise is calculated by the above formula (2) (Item (2) of Table 507). Furthermore, by calculating the product of the light quantity in the initial state when the light source 320 is set to a halogen lamp and the calculated change in light quantity, the light quantity in the opening regions 132A to 132C when the first polarizing filter 101 is rotated 10° counterclockwise is calculated (Item (3) of Table 507). These light intensity ratios are 0.994268∶1∶1.0242 (item (4)) in Table 507. By rotating the first polarizing filter 101 counterclockwise by 10°, the light intensity of the opening regions 132A to 132C can be well balanced.

[0145] When the light source 320 is set to an LED, by rotating the first polarizing filter 101 counterclockwise by 76°, the light intensity ratio in the opening regions 132A to 132C is close to 1:1:1, and the balance becomes good. Hereinafter, Table 507 will be used for explanation.

[0146] When the light source 320 is set as an LED, without the first polarizing filter 101 (initial state), a light quantity of 140 is obtained in the opening region 132A (“B”), a light quantity of 100 is obtained in the opening region 132B (“G”), and a light quantity of 30 is obtained in the opening region 132C (“R”) (item (5) of Table 507). The change in light quantity in each opening region 132A to 132C when the first polarizing filter 101 is rotated 76° counterclockwise is calculated by the above formula (2) (item (6) of Table 507). Furthermore, by calculating the product of the light quantity in the initial state when the light source 320 is set as an LED and the calculated change in light quantity, the light quantity in the opening regions 132A to 132C when the first polarizing filter 101 is rotated 76° counterclockwise is calculated (item (7) of Table 507). These light intensity ratios are 1.038306∶1∶0.984503 (item (8)) in Table 507. By rotating the first polarizing filter 101 counterclockwise by 76°, the light intensity of the opening regions 132A to 132C can be well balanced.

[0147] As explained above, by rotating the first polarizing filter 101 by a predetermined angle, even when the light source 320 is a halogen lamp or an LED, the light intensity ratio in the opening regions 132A to 132C can be close to 1:1:1, thereby ensuring a good balance of light intensity in each opening region.

[0148] (5th embodiment)

[0149] Next, the fifth embodiment will be described. Figure 18 Table 509 is a table illustrating the light intensity adjustment in the fifth embodiment. In this embodiment, the light source 320 is changed from a halogen lamp to an LED. Furthermore, ND filters 142A to 142C are set when the light source 320 is a halogen lamp and the rotation angle θ of the first polarizing filter 101 is -57°. Other settings are the same as in the first embodiment.

[0150] When the light source 320 changes from a halogen lamp to an LED, by rotating the first polarizing filter 101 counterclockwise by 57°, the light intensity ratio of the opening regions 132A to 132C can be made close to 1:1:1, thereby ensuring a good balance of light intensity in each opening region. Table 509 will be used for explanation below.

[0151] In the initial state (without the first polarizing filter 101 and without ND filters 142A to 142C) when the light source 320 is an LED or a halogen lamp, the same amount of light is obtained in the opening regions 132A to 132C as in the first embodiment (items (1) and (2) of Table 509). When the rotation angle of the first polarizing filter 101 is 57° counterclockwise, the change in the amount of light in each opening region 132A to 132C is calculated by the above formula (2) (item (3) of Table 509). The change in the amount of light in the ND filters 142A to 142C is set according to the case where the light source 320 is a halogen lamp (item (4) of Table 509). That is, the light intensity in the open region 132A (“B”) is 40×0.395742×1≈15.8296, the light intensity in the open region 132B (“G”) is 100×0.250463×0.632017≈15.8296, and the light intensity in the open region 132C (“R”) is 140×0.218296×0.517962≈15.8296 (product of items (2), (3), and (4) in Table 509).

[0152] On the other hand, when the light source 320 is changed from a halogen lamp to an LED, the above-mentioned light balance is disrupted because the ND filters 142A to 142C are set for halogen lamps (item (5) of Table 509).

[0153] Therefore, the light intensity is changed by rotating the first polarizing filter 101 counterclockwise by 169° (item (6) in Table 509). Thus, by rotating the first polarizing filter 101 counterclockwise by 169°, the light intensity of the aperture regions 132A to 132C changes (item (7) in Table 509). Furthermore, the light intensity ratio of the aperture regions 132A to 132C becomes 1.021719∶1∶1.028647, which can suppress the disruption of the light intensity balance even when the light source 320 is changed to an LED.

[0154] As explained above, when the ND filters 142A to 142C are set for halogen lamps, when the light source 320 is changed from a halogen lamp to an LED, the first polarizing filter 101 is rotated to change the polarization direction, thereby adjusting the light amount in the aperture regions 132A to 132C. This prevents the light amount balance in the aperture regions 132A to 132C from being disrupted.

[0155] (Sixth Embodiment)

[0156] Next, the sixth embodiment will be described. Figure 19Table 511 is a table illustrating the light intensity adjustment in the sixth embodiment. In this embodiment, the light source 320 is changed from an LED to a halogen lamp, and the ND filters 142A to 142C are set when the light source 320 is an LED and the first polarizing filter 101 is rotated 11° counterclockwise. Other settings are the same as in the first embodiment.

[0157] When the light source 320 is changed from a halogen lamp to an LED, by rotating the first polarizing filter 101 counterclockwise by 132°, the light intensity ratio of the opening regions 132A to 132C can be made close to 1:1:1, thus suppressing the disruption of the light intensity balance in each opening region. Table 511 will be used for explanation below.

[0158] In the initial state (without the first polarizing filter 101 and without ND filters 142A to 142C) when the light source 320 is an LED or a halogen lamp, the same amount of light is obtained in the opening regions 132A to 132C as in the first embodiment (items (1) and (2) of Table 511). When the first polarizing filter 101 is rotated counterclockwise to a position of 11°, the change in the amount of light in each opening region 132A to 132C is calculated by the above formula (2) (item (3) of Table 511). The change in the amount of light in the ND filters 142A to 142C is set according to the case where the light source 320 is an LED (item (4) of Table 511). That is, the light intensity in the opening region 132A (“B”) is 140×0.147053×1≈20.587, the light intensity in the opening region 132B (“G”) is 100×0.89386×0.23032=20.587, and the light intensity in the opening region 132C (“R”) is 30×0.982663×0.698353≈20.587 (the product of items (2), (3), and (4) in Table 511). Thus, when the light source 320 is an LED, the light intensity in the opening regions 132A to 132C is well balanced.

[0159] On the other hand, when the light source 320 is changed from an LED to a halogen lamp, the above-mentioned light balance is disrupted because the ND filters 142A to 142C are set for LEDs (item (5) of Table 511).

[0160] Therefore, the light intensity is changed by rotating the first polarizing filter 101 counterclockwise by 132° (item (6) in Table 511). Thus, by rotating the first polarizing filter 101 counterclockwise by 132°, the light intensity of the aperture regions 132A to 132C changes (item (7) in Table 511). Furthermore, the light intensity ratio of the aperture regions 132A to 132C becomes 1.046081∶1∶1.001267, which can suppress the disruption of the light intensity balance even when the light source 320 is changed to a halogen lamp.

[0161] As explained above, when the ND filters 142A to 142C are set for LEDs, when the light source 320 is changed from an LED to a halogen lamp, the first polarizing filter 101 is rotated to change the polarization direction. This prevents the light quantity balance in the opening regions 132A to 132C from being disrupted.

[0162] <Third Implementation Method>

[0163] Next, the third embodiment will be described. In this embodiment, the first polarization section is composed of a first polarizing filter 101 having multiple regions capable of independently changing the polarization direction. Furthermore, the amount of light in the opening regions 132A to 132C is adjusted by rotating the first polarizing filter 101.

[0164] Figure 20 This diagram conceptually illustrates the first polarizing filter 101 of this embodiment. The first polarizing filter 101 has three regions 101A to 101C, each capable of independently changing its polarization direction. Regions 101A to 101C can change their polarization direction by rotating around rotation axes LA to LC, respectively. Specifically, regions 101A to 101C each have a unidirectional polarization direction, and by rotating around rotation axes LA to LC, the polarization direction of light passing through the region can be changed. Furthermore, region 101A corresponds to open region 132A, region 101B corresponds to open region 132B, and region 101C corresponds to open region 132C.

[0165] Thus, in this embodiment, the amount of light in each region can be adjusted by the interaction between the polarization direction of regions 101A to 101C of the first polarizing filter 101 and the polarization direction of the second polarizing filter.

[0166] Light intensity variation α in the opening region 132A–132C i It is represented by the following equation (3). In addition, the change in light intensity in the opening region 132A is represented by the change in light intensity α0, the change in light intensity in the opening region 132B is represented by the change in light intensity α1, and the change in light intensity in the opening region 132C is represented by the change in light intensity α2.

[0167] [Formula 6]

[0168] Light change α i =cos 2 (ψ i -φ i (3)

[0169] In addition, the following values ​​are represented in the above formula (3).

[0170] [Formula 7]

[0171] Polarization angle of opening region 132A: Φ0

[0172] Polarization angle of opening region 132B: Φ1

[0173] Polarization angle of opening region 132C: Φ2

[0174] [Formula 8]

[0175] Polarization angle of region 101A: Ψ0

[0176] Polarization angle of region 101B: Ψ1

[0177] Polarization angle of region 101C: Ψ2

[0178] As explained above, the amount of light in the opening regions 132A to 132C can be adjusted using the region of the first polarizing filter 101 and the second polarizing filters 148A to 148C.

[0179] The following describes an embodiment of adjusting the light intensity in the opening regions 132A to 132C.

[0180] (Seventh Embodiment)

[0181] Figure 21 Table 513 is a table illustrating the light intensity adjustment in the seventh embodiment. Furthermore, in this example, the ND filter 142 is not used. Also, the wavelength selection filters 144A-144C and the second polarizing filters 148A-148C disposed in each aperture region are the same as in the first embodiment.

[0182] When the light source 320 is a halogen lamp, by setting the polarization angle of region 101A of the first polarizing filter 101 to 4°, the polarization angle of region 101B to 9°, and the polarization angle of region 101C to -2°, the light intensity ratio in the opening regions 132A to 132C is close to 1:1:1, which can achieve a good balance of light intensity in each opening region. Table 513 will be used for explanation below.

[0183] When the light source 320 is a halogen lamp, without the first polarizing filter 101 (initial state), a light quantity of 40 is obtained in the opening region 132A (“B”), a light quantity of 100 is obtained in the opening region 132B (“G”), and a light quantity of 140 is obtained in the opening region 132C (“R”) (Item (1) of Table 513). The changes in light quantity in each opening region 132A to 132C when the polarization direction of region 101A of the first polarizing filter 101 is set to 4°, the polarization direction of region 101B is set to 9°, and the polarization direction of region 101C is set to -2° are calculated by the above formula (3) (Item (2) of Table 513). Furthermore, by calculating the product of the initial light quantity when the light source 320 is set to a halogen lamp and the calculated light quantity change, the light quantity in the opening regions 132A to 132C when each region 101A to 101C of the first polarizing filter 101 is set as described above is calculated (item (3) of Table 513). These light quantity ratios are 1.005074∶1∶0.992668 (item (4) of Table 513). By setting the polarization direction of region 101A of the first polarizing filter 101 to 4°, the polarization direction of region 101B to 9°, and the polarization direction of region 101C to -2°, the light quantity in the opening regions 132A to 132C can be well balanced.

[0184] When the light source 320 is set to an LED, by setting the polarization direction of region 101A of the first polarizing filter 101 to -71°, the polarization direction of region 101B to -8°, and the polarization direction of region 101C to -14°, the light intensity ratio in the opening regions 132A to 132C is close to 1:1:1, which can achieve a good balance of light intensity in each opening region. Table 513 will be used for explanation below.

[0185] When the light source 320 is set as an LED, without setting the first polarizing filter 101 (initial state), a light quantity of 140 is obtained in the opening region 132A (“B”), a light quantity of 100 is obtained in the opening region 132B (“G”), and a light quantity of 30 is obtained in the opening region 132C (“R”) (item (5) of Table 513). The changes in light quantity in each opening region 132A to 132C when the polarization direction of region 101A of the first polarizing filter 101 is set to -71°, the polarization direction of region 101B is set to -8°, and the polarization direction of region 101C is set to -14° are calculated by the above formula (3) (item (6) of Table 513). Furthermore, by calculating the product of the initial light quantity when the light source 320 is set as an LED and the calculated light quantity change, the light quantity in the opening regions 132A to 132C when the regions 101A to 101C of the first polarizing filter 101 are set as described above is calculated (item (7) of Table 513). These light quantity ratios are 1.057453∶1∶1.031604 (item (8) of Table 513). By setting the polarization direction of the regions 101A to 101C of the first polarizing filter 101 as described above, the light quantity in the opening regions 132A to 132C can be well balanced.

[0186] As explained above, by setting the polarization direction of regions 101A to 101C of the first polarizing filter 101 to a specified angle, even when the light source 320 is a halogen lamp or an LED, the light intensity ratio in the opening regions 132A to 132C can be close to 1:1:1, thereby ensuring a good balance of light intensity in each opening region.

[0187] <Another example of the first polarization section>

[0188] In the examples of the first to third embodiments described above, the case in which the first polarizing filter 101 is provided as the first polarizing part on the front surface of the imaging optical system 100A on the object side has been described (see reference). Figure 5 However, in this invention, another method of using the first polarization section is also possible. Hereinafter, another example of the first polarization section will be described.

[0189] Figure 22This diagram illustrates another example of the first polarization section. In this example, the first polarizing filter 101, constituting the first polarization section, is rotatably disposed within the imaging optical system 100A. It is positioned closer to the object side than the wavelength polarizing filter unit 130. Specifically, the first polarizing filter 101 is disposed adjacent to the object side of the intermediate filter A in a manner that allows it to rotate around the optical axis L. In this case, the first polarizing filter 101 is disposed at or near the pupil position of the imaging optical system 100A, thereby being adjacent to the object side of the intermediate filter A. As a result, the light intensity difference generated in the portion of the aperture region near the optical axis L and the peripheral portion can be suppressed.

[0190] Figure 23 This diagram illustrates another example of the first polarization section. In this example, the first polarization section comprises a first polarizing filter 101 and a liquid crystal polarization rotation element C disposed on the image side of the first polarizing filter 101. The first polarizing filter 101 is fixed to allow light with a unidirectional polarization direction to pass through. The liquid crystal polarization rotation element C polarizes the light that has passed through the first polarizing filter 101. By changing the applied voltage, the liquid crystal polarization rotation element C changes the orientation of the liquid crystal molecules, thereby changing the polarization direction of the light that has passed through the first polarizing filter 101. Therefore, the polarization direction of the light that has passed through the first polarizing filter 101 can be freely changed.

[0191] <Control of polarization direction of the first polarization section>

[0192] As described above, in the first to third embodiments, the light intensity of the opening regions 132A to 132C is adjusted by controlling the polarization direction of the first polarizing unit. Furthermore, the polarization direction of the first polarizing unit is controlled automatically or manually as described below.

[0193] The case of automatically controlling the polarization direction of the first polarizing unit will be explained. For example, the polarization direction of the first polarizing unit is automatically controlled by a polarization direction control unit consisting of a CPU provided in the lens device 100 or a CPU provided in the camera device main body 200. When the first polarizing unit is composed of a first polarizing filter 101 as described in the first embodiment, the polarization direction control unit rotates the first polarizing filter 101 to adjust the light amount in the aperture regions 132A to 132C. The polarization direction control unit controls the polarization direction of the first polarizing filter 101 by rotating it according to the light amount ratio of each of the aperture regions 132A to 132C. The polarization direction control unit rotates the first polarizing filter 101 to achieve a good balance in the light amount ratio of each of the aperture regions 132A to 132C.

[0194] Next, the case of manually controlling the polarization direction of the first polarizing section will be explained. For example, the lens device 100 includes a polarization direction limiting section that restricts the polarization direction of the first polarizing section to a predetermined position. When the first polarizing section is composed of a first polarizing filter 101 as described in the first embodiment, the polarization direction limiting section is set such that when the user manually rotates the first polarizing filter 101, the rotation stops at a position where the balance of the light intensity ratio in the opening regions 132A to 132C becomes good. In the first embodiment, when the light source 320 is a halogen lamp, the polarization direction limiting section is set such that the first polarizing filter 101 stops rotating at a position of 4° clockwise. Furthermore, when the light source 320 is an LED, the polarization direction limiting section is set such that the first polarizing filter 101 stops rotating at a position of 63° counterclockwise. Thus, when the user rotates the first polarizing filter 101, the first polarizing filter 101 can be stopped at a position where the balance of the light intensity ratio in each of the opening regions 132A to 132C becomes good.

[0195] <Fourth Implementation Method>

[0196] Next, the fourth embodiment will be described. In the first to third embodiments described above, the first polarizing unit polarizes the light transmitted through the imaging optical system 100A in various directions, and adjusts the amount of light in the opening regions 132A to 132C by interacting with the polarization directions of the second polarizing filters 148A to 148C. That is, in the first to third embodiments, the first polarizing unit is configured to change the polarization direction of the transmitted light. In the fourth embodiment, instead of the first polarizing unit that can change the polarization direction of the light, a first polarizing filter 101 with a fixed polarization direction is provided in the wavelength polarizing filter unit 130.

[0197] Figure 24 and Figure 25 This diagram conceptually represents the first polarizing filter 101 and the wavelength polarizing filter unit 130. Furthermore, the first polarizing filter 101 and the wavelength polarizing filter unit 130 are integrally bonded together to form an optical component. In the following description, filter groups 140A to 140C are collectively referred to as filter group 140, ND filters 142A to 142C are collectively referred to as ND filters 142, wavelength selective filters 144A to 144C are collectively referred to as wavelength selective filters 144, optical path length correction filters 146A to 146C are collectively referred to as optical path length correction filters 146, and second polarizing filters 148A to 148C are collectively referred to as second polarizing filters 148.

[0198] The wavelength polarization filter unit 130 of this embodiment has a first polarization filter 101 on the object side. Figure 24The first polarizing filter 101 shown and Figure 25 The polarization directions of the first polarizing filter 101 shown are different. On the other hand, Figure 24 and Figure 25 The second polarizing filter 148 has the same polarization direction. Thus, by preparing multiple optical components that each change the polarization direction of the first polarizing filter 101, and by replacing these optical components, the light intensity ratio of the aperture regions 132A to 132C can be changed. Furthermore, in the aforementioned optical components, the first polarizing filter 101 is positioned closest to the object side, and the second polarizing filter 148 is positioned closest to the image side, thereby reducing the light intensity in the aperture regions 132A to 132C and suppressing crosstalk between the aperture regions 132A to 132C.

[0199] <Example of a filter set>

[0200] Next, the filter group 140 described above will be explained. Hereinafter, the configuration of each filter constituting the filter group 140 will be explained.

[0201] First, the configuration of the second polarizing filter 148 in the filter group 140 will be explained.

[0202] Figure 26 and Figure 27 This diagram illustrates the configuration of the second polarizing filter 148. Additionally, the filters indicated by the symbol X include an ND filter 142, a wavelength-selective filter 144, and an optical path length correction filter 146. (As shown...) Figure 26 and Figure 27 As shown, the second polarizing filter 148 is preferably disposed closest to the image side in the filter group 140. In this way, by disposing the second polarizing filter 148 closest to the image side in the filter group 140, the polarization characteristics caused by the transmission of other filters (ND filter 142, wavelength selective filter 144, and optical path length correction filter 146) can be eliminated by the second polarizing filter 148.

[0203] In addition, Figure 27 In this case, since all the filters of the filter group 140 are arranged on the object side of the frame 132, the second polarizing filter 148 is arranged on the image side of the region boundary member 132(α).

[0204] Next, the configuration of the second polarizing filter 148 and the wavelength selective filter 144 in the filter group 140 will be described.

[0205] Figure 28 and Figure 29 This diagram illustrates the configuration of the wavelength selection filter 144 and the second polarizing filter 148. Additionally, the filters indicated by the symbol X include an ND filter 142 and an optical path length correction filter 146. (As shown...) Figure 28 and Figure 29 As shown, the second polarizing filter 148 is positioned further away from the image side than the wavelength selective filter 144. Thus, by positioning the second polarizing filter 148 further away from the image side than the wavelength selective filter 144, the polarization characteristics caused by transmission through the wavelength selective filter 144 can be eliminated using the second polarizing filter 148.

[0206] Next, the configuration of the ND filter 142 and the wavelength selective filter 144 in the filter group 140 will be described.

[0207] Figure 30 This diagram illustrates the configuration of the ND filter 1.42 and the wavelength selective filter 144. Additionally, the filter indicated by symbol X includes an optical path length correction filter 146 and a second polarizing filter 148. (As shown...) Figure 30 As shown, the ND filter 142 is positioned closer to the object than the wavelength selective filter 144. This allows for the suppression of light spots or ghosting caused by strong reflected light from the surface of the wavelength selective filter 144.

[0208] Next, the configuration of the ND filter 142 in the filter group 140 will be described.

[0209] Figure 31 and Figure 32 This diagram illustrates the configuration of the ND filter 142. Additionally, the filter indicated by symbol X includes a wavelength-selective filter 144, an optical path length correction filter 146, and a second polarizing filter 148. Figure 31 In this configuration, the ND filter 142 is positioned closest to the object within the filter group 140. By positioning the ND filter 142 closest to the object, light is reduced before being reflected by the wavelength-selective filter 144, thereby suppressing ghosting and facilitating subsequent adjustments. Figure 32 In this configuration, the ND filter 142 is positioned closest to the image side in the filter group 140. This allows for easy installation of the ND filter 142 and facilitates subsequent adjustments.

[0210] Next, the configuration of the optical path length correction filter 146 in the filter group 140 will be explained.

[0211] Figure 33 and Figure 34 This diagram illustrates the configuration of the optical path length correction filter 146. Additionally, the filter indicated by symbol X includes an ND filter 142, a wavelength selective filter 144, and a second polarizing filter 148. Figure 33 In this configuration, the optical path length correction filter 146 is positioned closest to the object. Furthermore, in... Figure 34In this configuration, the optical path length correction filter 146 is positioned closest to the image side. This allows for easy installation and subsequent adjustment of the optical path length correction filter 146.

[0212] The above description illustrates examples of the present invention, but the present invention is not limited to the above embodiments. Various modifications can be made without departing from the spirit of the present invention.

[0213] Symbol Explanation

[0214] 10-Camera device, 100-Lens device, 100A-Camera optical system, 100B-Illumination device, 101-First polarizing filter, 102-Lens barrel, 108-Slit, 110-First lens, 120-Second lens, 130-Wavelength polarizing filter unit, 132-Frame, 200-Camera device body, 210-Imaging element, 211-Pixel array layer, 212-Photodiode, 213 - Polarizing filter element array layer, 214A- Polarizing filter element, 214B- Polarizing filter element, 214C- Polarizing filter element, 214D- Polarizing filter element, 215- Microlens array layer, 216- Microlens, 230- Signal processing unit, 232- Analog signal processing unit, 234- Image generation unit, 236- Coefficient storage unit, 310- Light source control unit, 320- Light source, L- Optical axis.

Claims

1. A lens device comprising: Camera optical system; The first polarizing section polarizes at least a portion of the light transmitted through the imaging optical system; and A filter unit is configured further to the image side than the first polarizing section and is located at or near the pupil position of the imaging optical system. The filter unit includes: Multiple opening areas allow light from the camera optical system to pass through, including a first opening area and a second opening area; Multiple wavelength selective filters are disposed in the first aperture region and the second aperture region, allowing light of at least a portion of different wavelength bands to pass through; and a second polarizing filter is disposed in the first aperture region and the second aperture region, and has multiple polarizing filters with mutually different polarization directions. The amount of light in the first opening region and the second opening region is adjusted according to the difference in polarization direction between the first polarizing part and the second polarizing filter.

2. The lens device according to claim 1, wherein, The polarization direction of the first polarization section is variable.

3. The lens device according to claim 1 or 2, wherein, The first polarizing section is a first polarizing filter that rotates around the optical axis.

4. The lens device according to claim 1 or 2, wherein, The first polarizing section is disposed on the object side of the lens included in the imaging optical system.

5. The lens device according to claim 1 or 2, wherein, The first polarizing section is disposed within the imaging optical system and is positioned closer to the object side than the filter unit.

6. The lens device according to claim 1 or 2, wherein, The first polarization section has multiple regions with different polarization directions.

7. The lens device according to claim 1 or 2, wherein, The first polarization section has multiple regions capable of independently changing the polarization direction, and the multiple regions rotate along their respective rotation axes.

8. The lens device according to claim 1 or 2, wherein, The second polarizing filter is disposed on the image side of the plurality of wavelength selective filters.

9. The lens device according to claim 1 or 2, wherein, The filter unit further includes multiple optical path length correction filters, which are disposed in the first opening region and the second opening region to correct the on-axis chromatic aberration caused by the multiple wavelength selective filters.

10. The lens device according to claim 1 or 2, wherein, The filter unit further includes an ND filter, which is disposed in the first opening region and the second opening region to reduce the amount of light from the camera optical system.

11. The lens device according to claim 1, wherein, The first polarization section is composed of a polarization filter and a liquid crystal polarization rotation element disposed on the image side of the polarization filter.

12. The lens device according to claim 1 or 2, wherein, The lens device includes a polarization direction control unit, which controls the polarization direction of the first polarization unit. The polarization direction control unit controls the polarization direction of the first polarization unit based on the ratio of the light quantity corresponding to the first opening region to the light quantity corresponding to the second opening region.

13. The lens device according to claim 1 or 2, wherein, The lens device includes a polarization direction limiting part, which limits the polarization direction of the first polarization part to a predetermined position. The polarization direction limiting unit limits the polarization direction of the first polarization unit based on the ratio of the light quantity corresponding to the first opening region to the light quantity corresponding to the second opening region.

14. A camera device comprising a lens device according to any one of claims 1 to 13.

15. An optical component disposed at or near the pupil position of a camera optical system, comprising: A first polarizing filter polarizes at least a portion of the light transmitted through the imaging optical system; and Multiple opening regions allow light from the camera optical system to pass through, including a first opening region and a second opening region. The optical component includes: Multiple wavelength selective filters are disposed in the first opening region and the second opening region, allowing light of at least a portion of different wavelength bands to pass through; and A second polarizing filter is disposed in the first opening region and the second opening region, and has multiple polarizing filters with different polarization directions. The first polarizing filter is positioned closest to the object side, and the second polarizing filter is positioned closest to the image side. The amount of light in the first and second opening regions is adjusted according to the difference in polarization direction between the first and second polarizing filters.

16. A camera device comprising the optical component of claim 15.

17. An optical component included in a camera device, the camera device having a polarizing section, the optical component being disposed at or near a pupil position of a camera optical system, having a plurality of opening regions through which light from the camera optical system passes, including a first opening region and a second opening region, the polarizing section polarizing at least a portion of the light passing through the camera optical system, the optical component comprising: An ND filter is disposed in the first opening region and the second opening region to reduce the amount of light emitted by the imaging optical system; Multiple wavelength selective filters are disposed in the first opening region and the second opening region, allowing light of at least a portion of different wavelength bands to pass through; and Multiple optical path length correction filters are disposed in the first opening region and the second opening region to correct on-axis chromatic aberration caused by the multiple wavelength selective filters; and Multiple polarizing filters are disposed in the first opening region and the second opening region, and their polarization directions are different from each other. The optical path length correction filter is positioned further on the image side than the wavelength selection filter. The amount of light in the first opening region and the second opening region is adjusted according to the difference in polarization direction between the polarizing part and the plurality of polarizing filters.

18. A camera device comprising the optical component and the polarizing portion as described in claim 17.

Images