Optical devices

Abstract

To provide an optical member holding configuration which, even if either one of an eyepiece in contact with ambient atmosphere and a second eyepiece counted from the outside is made of plastic material, prevents surface accuracy and resolution from deteriorating and an image from being deformed, and further inhibits dew condensation caused by intrusion of moisture vapor into the eyepiece.SOLUTION: An optical device of the present invention comprises a second optical member 402 and a first holding member 403. The second optical member includes at its periphery a contact part 402c for tightly contacting a second sealing member 405. The first holding member includes at its periphery a contact part 403c for tightly contacting the second sealing member 405. The first optical member 401 and the first holding member 403 are tightly sealed by a first sealing member 404. A space between the first optical member 401 and the second optical member 402 is tightly sealed.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a sealing structure for an optical device in which a plurality of optical members are arranged in the optical axis direction. For example, the present invention relates to a sealing structure for an optical device that constitutes a viewfinder unit such as a camera body. Background Art

[0002] Conventionally, when a camera is suddenly moved from a warm indoor environment to a low-temperature environment such as winter, a cold region, or nighttime, a temperature difference occurs between the outside air temperature and the inside of the camera.

[0003] Accordingly, a decrease in the temperature of the inner side of the eyepiece, which is in contact with outside air, reduces the saturated water vapor content of water vapor inside the camera, which may cause dew condensation on the inner surface of the eyepiece that is in contact with outside air.

[0004] Furthermore, the camera is turned on in a high-humidity and low-temperature environment such as a rainy day.

[0005] When turned on, heat generated by integrated circuits on an electric board and heat from a backlight for a display element inside the viewfinder increases the temperature inside the camera, which may similarly cause dew condensation on the inner side of the eyepiece that is in contact with outside air.

[0006] In any case, users cannot wipe the inner side of the eyepiece, and dew condensation causes a problem of reduced visibility.

[0007] To address the above problem, dew condensation can be reduced by adopting a configuration that prevents water vapor from entering the inner side of the eyepiece that is in contact with outside air.

[0008] Accordingly, as disclosed in Patent Document 1, a method has been proposed in which the space between the outermost lens and the second lens from the outside is annularly bonded to each other with an adhesive medium, thereby suppressing the intrusion of water vapor into the inner side of the eyepiece that is in contact with outside air. Prior Art Documents Patent Documents

[0009] [Patent Document 1] Japanese Patent Publication No. 2021-135354 [Overview of the project] [Problems that the invention aims to solve]

[0010] However, in the prior art disclosed in Patent Document 1 mentioned above, if the eyepiece lens that comes into contact with the outside air and the second lens from the outside are made of glass, the shrinkage during the curing of the adhesive is not affected, and it is possible to bond the entire circumference.

[0011] However, to reduce costs and weight, plastic materials are commonly used for eyepieces.

[0012] When using plastic material for eyepieces, if the entire circumference is bonded, the shrinkage of the adhesive during curing causes the lens to deform. This leads to a deterioration in the surface accuracy of the lens, resulting in reduced resolution and image distortion.

[0013] Therefore, when bonding plastic lenses, the bonding is often done only at specific points, within a range that does not affect the deterioration of surface accuracy due to lens deformation, rather than bonding the entire circumference.

[0014] In that case, if at least one of the eyepiece lenses that come into contact with the outside air, or the second lens from the outside, is made of plastic, it is not possible to bond the entire circumference.

[0015] Therefore, it is not possible to suppress the intrusion of water vapor into the inside of the eyepiece lens using the prior art disclosed in Patent Document 1.

[0016] Therefore, the objective of the present invention is to prevent deterioration of surface accuracy, reduction in resolution, and image distortion even if either the eyepiece exposed to the outside air or the second eyepiece from the outside is made of plastic.

[0017] Another object of the present invention is to provide a holding configuration for an optical member that can suppress dew condensation caused by water vapor entering the inner side of an eyepiece. Means for Solving the Problem

[0018] To achieve the above object, the optical device of the present invention includes: a first optical member in contact with outside air; a first optical member in contact with outside air; The second plastic object located in the optical axis direction from the outside air side a second optical member; a first holding member that holds the first optical member and the second optical member; a first sealing member that seals a gap between the first optical member and the first holding member; and a member that seals a gap between the first holding member and the second optical member Sheet-like a second sealing member; wherein the optical device comprises: the first optical member is held on one side in the optical axis direction of the first holding member, the second optical member is held on the other side of the first holding member, and an outer peripheral portion on the other side of the first holding member The aforementioned provided on The plane perpendicular to the optical axis a flat surface portion First and an outer peripheral portion on the other side of the second optical member 、 provided on The plane perpendicular to the optical axis a flat surface portion second and , on the same side are The first planar portion and the second planar portion are formed, in close contact with a flat surface portion provided on the one side of the second sealing member. Effect of the Invention

[0019] Even if either one of the eyepiece in contact with outside air and the second eyepiece from the outside is made of a plastic material, deterioration of surface accuracy, reduction in resolution, image distortion and the like do not occur.

[0020] Furthermore, it is possible to provide a holding configuration for an optical member that can suppress dew condensation caused by water vapor entering the inner side of an eyepiece. Brief Description of the Drawings

[0021] [Figure 1]It is an external perspective view of the digital camera 100. [Figure 2] It is a cross-sectional view of the eyepiece unit 16. [Figure 3] It is an exploded perspective view of the eyepiece unit 16 [Figure 4] It is an exploded perspective view before incorporating the optical member 413 into the lens holding member 409. [Figure 5] It is an exploded perspective view before assembling the spacer 412 to the lens holding member 409. [Figure 6] It is an exploded perspective view before incorporating the optical member 408 into the lens holding member 409. [Figure 7] It is an exploded perspective view before incorporating the spacer 411 into the lens holding member 409. [Figure 8] It is an exploded perspective view before incorporating the elastic member 410 into the lens holding member 409. [Figure 9] It is an exploded perspective view before fixing the optical member 401 to the lens holding member 403 with the sealing member 404. [Figure 10] It is an exploded perspective view before incorporating the optical member 402 into the lens holding member 403. [Figure 11] It is an exploded perspective view before sealing the gap between the lens holding member 409 and the optical member 402 with the sealing member 405. [Figure 12] It is an exploded perspective view before combining the lens holding member 409 and the lens holding member 403. MODE FOR CARRYING OUT THE INVENTION

[0022] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0023] (External Perspective View of Digital Camera 100) Figs. 1(A) and 1(B) are external perspective views of a digital camera 100 as an example of an optical apparatus to which the present invention can be applied.

[0024] These optical devices may include, for example, mobile phones, game consoles, tablet devices, personal computers, watch-type or glasses-type information terminals, and head-mounted displays.

[0025] It can also be applied to products with eyepieces (e.g., monoculars, binoculars, rangefinders, etc.) and eyepiece accessories that attach to eyepieces (e.g., rain covers, magnifiers, angle finders, etc.). Figure 1(A) is a perspective view of the digital camera 100 as seen from the front, and Figure 1(B) is a perspective view of the digital camera 100 as seen from the rear.

[0026] In Figure 1, the eyecup 802 is made of a soft material or the like in order to prevent light from entering the viewfinder through the gap between the eyepiece frame 801 and the photographer.

[0027] The diopter adjustment dial 900 is used to adjust the position of the EVF module 29 (shown in Figure 2), which will be described later, according to the user's diopter.

[0028] The eyepiece section 16 is a magnifying optical system for the eyepiece viewfinder (a type of viewfinder that you look through), allowing the user to view a magnified image displayed on the internal EVF module 29 through the eyepiece section 16.

[0029] The EVF module 29 is a display device such as an LCD or organic EL, and displays information in response to an analog signal from a D / A converter (not shown).

[0030] The display on the EVF module 29 is shorter in the vertical direction than in the horizontal direction when the digital camera 100 is held in the correct position.

[0031] (Eyepiece configuration) Next, the configuration of the eyepiece section 16 as an optical device in this embodiment will be explained using Figures 2 and 3.

[0032] Figure 2 shows the cross-sectional configuration of the eyepiece section 16.

[0033] Figure 3 is an exploded perspective view of the eyepiece section 16. Figure 2 is a vertical cross-sectional view centered on the optical axis 1000 of the eyepiece 16 when a camera 100 (not shown) is held in the upright position. In this figure, the left side shows the EVF module 29 side, and the right side shows the observer side.

[0034] The eyepiece section 16 is a magnifying optical system that magnifies the image displayed on the EVF module 29 for observation by the photographer, and is provided as a viewfinder for digital cameras, mirrorless cameras, or digital video cameras, etc. It is either integrated with the imaging device or detachable.

[0035] Optical elements 402, 408, and 413 are plastic lenses, and optical element 401 is a flat cover window. Optical element 401 is made of plastic or glass.

[0036] Optical element 402 has a lens shape that is convex toward optical element 401.

[0037] In this embodiment, the optical element 401 is flat, but it may also be lens-shaped.

[0038] In this embodiment, the optical member 402 is convex toward the optical member 401, and the optical member 401 has a flat plate shape. As will be described later, when the space between the optical member 401 and the optical member 402 is sealed, the volume can be reduced by having a convex lens fit into the space.

[0039] Furthermore, by shortening the distance between optical elements 401 and 402 near the optical axis 1000, the air layer near the optical axis 1000 is reduced, making the central part that the user looks into less likely to fog up during use.

[0040] Furthermore, because the optical element 401 in contact with the outside air is a flat plate, temperature variations in the optical element 401 are less likely to occur, resulting in a uniform and less prone to fogging.

[0041] 403 is a lens holding member that holds optical elements 401 and 402, and 409 is a lens holding member that holds optical elements 408 and 413.

[0042] 411 and 412 are spacers that determine the distance between optical elements 413, 408, and 402, and may also serve as masks to prevent unwanted light from entering the optical elements 413, 408, and 402.

[0043] 410 is an elastic member for pressing the optical members 413, 408, 402 and spacers 412, 411 against the lens holding members 409 and 403, and is made of an elastic material such as silicone rubber.

[0044] 404 is a sealing member for sealing and holding the optical component 401 in the lens holding member 403, and in this embodiment it is a double-sided tape made of a polyolefin foam base material coated with an acrylic adhesive.

[0045] If the optical component 401 is made of glass, the optical component 401 will be more resistant to external forces such as deformation.

[0046] Therefore, as long as the gap between the lens holding member 403 and the optical member 401 can be sealed, it is not limited to double-sided tape; for example, a UV-effect type or anaerobic adhesive may also be used.

[0047] Furthermore, the sealing member 404 may also serve as a mask to prevent unwanted light from entering the optical members 402 and 401.

[0048] 405 is a sheet-like sealing member for sealing the optical component 402 and the lens holding member 403.

[0049] In this embodiment, a single-sided adhesive tape or double-sided tape made of a polyolefin foam base material coated with an acrylic adhesive, or a sheet material such as elastic, non-adhesive silicone rubber may be used.

[0050] Furthermore, the sealing member 405 may also serve as a mask to prevent unwanted light from entering the optical members 402 and 408. In addition, the effectiveness of the sealing members 404 and 405 can be enhanced by using a material with low moisture permeability, such as polyethylene film, as the base material.

[0051] By rotating the diopter adjustment dial 900 (shown in Figure 1), the EVF module 29 can be moved in the direction of the optical axis 1000 via a cam mechanism (not shown).

[0052] This allows the user to adjust the position of the EVF module 29 to match their diopter.

[0053] In this embodiment, the EVF module 29 is configured to move when the diopter adjustment dial 900 is used, so that the relative positions of optical elements 401 and 402 do not change even when the user adjusts the diopter.

[0054] The optical effective range of optical components 401, 402, 408, and 412 is configured to be shorter in the vertical direction than in the horizontal direction when the digital camera 100 is held in the upright position, in accordance with the display of the EVF module 29.

[0055] Next, the detailed configuration of the eyepiece section 16 will be explained using Figures 4 to 12, following the order of assembly.

[0056] (Expanded perspective view before the optical element 413 is assembled into the lens holding member 409) Figure 4 is an exploded perspective view of the lens holder member 409 before the optical element 413 is assembled into it.

[0057] The 413c1 to 413c6 provided on the outer circumference of the optical element 413 are radial receiving surfaces that perform radial positioning with respect to the lens optical axis 1000 (Figure 2).

[0058] The optical member 413 is positioned radially so that its optical axis aligns with the optical axis 1000 of the eyepiece section 16 by contacting the radial receiving surfaces 409c1 to 409c6 provided on the inner circumference of the lens holding member 409.

[0059] 413a1~413a3 and 413b1~413b3 are thrust receiving surfaces that position the optical element 413 in the thrust direction with respect to the optical axis 1000 of the eyepiece 16.

[0060] The aforementioned thrust receiving surfaces 413a1 to 413a3 and 413b1 to 413b3 are located on the outer periphery of the optical member 413, outside the optically effective range, and are provided at three points each on the front and back of the optical member 413, with the front and back positions being approximately the same location in the projection along the optical axis.

[0061] By holding the optical element 413 in contact only with these thrust bearing surfaces 413a1-413a3 and 413b1-413b3, bending stress is less likely to be applied to the optical element 413, resulting in a configuration that is less prone to a decrease in optical performance due to deformation.

[0062] These thrust receiving surfaces 413a1 to 413a3 come into contact with thrust receiving surfaces 409a1 to 409a3 provided on the lens holding member 409, thereby determining the thrust position of the optical member 413.

[0063] (Expanded perspective view before spacer 412 is assembled to lens holding member 409) Figure 5 is an exploded perspective view after the optical element 413 has been assembled into the lens holding member 409, but before the spacer 412 has been assembled.

[0064] The 412c1 to 412c6 provided on the outer circumference of the spacer 412 are radial receiving surfaces that perform radial positioning with respect to the lens optical axis 1000 (Figure 2).

[0065] The radial receiving surfaces 409d1 to 409d6 provided on the inner circumference of the lens holding member 409 are used to position the spacer 412 radially so that its optical axis aligns with the optical axis 1000 of the eyepiece 16.

[0066] 412a1~412a3 and 412b1~412b3 are thrust receiving surfaces that position the spacer 412 in the thrust direction with respect to the optical axis 1000 of the eyepiece 16.

[0067] The aforementioned thrust receiving surfaces 412a1 to 412a3 and 412b1 to 412b3 are provided at three points each on the front and back of the spacer 412, with the front and back positions being approximately the same location projected in the optical axis direction.

[0068] By holding only these thrust bearing surfaces 412a1~412a3 and 412b1~412b3 in contact, bending stress is less likely to be applied to the spacer 412.

[0069] This configuration makes it less likely for the positional accuracy of the thrust receiving surfaces 412a1-412a3 and 412b1-412b3 to deteriorate.

[0070] These thrust receiving surfaces 412a1 to 412a3 come into contact with the thrust receiving surfaces 413b1 to 413b3 of the optical member 413, thereby determining the thrust position of the spacer 412.

[0071] (Expanded perspective view before the optical element 408 is assembled into the lens holding member 409) Figure 6 is an exploded perspective view of the lens holder member 409 after the optical member 413 and spacer 412 have been assembled, but before the optical member 408 has been assembled.

[0072] The 408c1 to 408c6 provided on the outer circumference of the optical element 408 are radial receiving surfaces that perform radial positioning with respect to the lens optical axis 1000 (Figure 2).

[0073] The optical member 408 is positioned in the radial direction so that its optical axis aligns with the optical axis 1000 of the eyepiece section 16 by contacting the radial receiving surfaces 409f1 to 409f6 provided on the inner circumference of the lens holding member 409.

[0074] 408a1~408a3 and 408b1~408b3 are thrust receiving surfaces that position the optical element 408 in the thrust direction with respect to the optical axis 1000 of the eyepiece 16.

[0075] The aforementioned thrust receiving surfaces 408a1 to 408a3 and 408b1 to 408b3 are located on the outer periphery of the optical member 408, outside the optically effective range, and are provided at three points each on the front and back of the optical member 408, with the front and back positions being approximately the same location projected in the optical axis direction.

[0076] By holding the optical element 408 only through contact between these thrust bearing surfaces 408a1-408a3 and 408b1-408b3, bending stress is less likely to be applied to the optical element 408, resulting in a configuration that is less prone to degradation of optical performance due to deformation.

[0077] These thrust receiving surfaces 408a1 to 408a3 come into contact with thrust receiving surfaces 409e1 to 409e3 provided on the lens holding member 409, thereby determining the thrust position of the optical member 408.

[0078] As described above, the optical members 413 and 408 are held in contact with the lens holding member 409 at separate positions.

[0079] This allows for the correction of each optical component individually when tilting occurs due to the dimensions of the parts, and the height of the three thrust bearing surfaces needs to be adjusted to correct the tilt.

[0080] (Expanded perspective view before spacer 411 is incorporated into lens holder 409) Figure 7 is an exploded perspective view of the lens holder member 409 after the optical member 413, spacer 412, and optical member 408 have been assembled, but before the spacer 411 has been assembled.

[0081] The 411c1 to 411c6 provided on the outer circumference of the spacer 411 are radial receiving surfaces that perform radial positioning with respect to the lens optical axis 1000 (Figure 2).

[0082] The radial receiving surfaces 409g1 to 409g6 provided on the inner circumference of the lens holding member 409 are used to position the spacer 411 radially so that its optical axis aligns with the optical axis 1000 of the eyepiece 16.

[0083] 411a1~411a3 and 411b1~411b3 are thrust receiving surfaces that position the spacer 411 in the thrust direction with respect to the optical axis 1000 of the eyepiece 16.

[0084] The aforementioned thrust receiving surfaces 411a1 to 411a3 and 411b1 to 411b3 are provided at three points each on the front and back of the spacer 411, with the front and back positions being approximately the same location projected in the optical axis direction.

[0085] By holding the spacer 411 only through contact between these thrust bearing surfaces 411a1-411a3 and 411b1-411b3, bending stress is less likely to be applied to the spacer 411.

[0086] This configuration makes it less likely for the positional accuracy of the thrust receiving surfaces 411a1-411a3 and 411b1-411b3 to deteriorate.

[0087] These thrust receiving surfaces 411a1 to 411a3 come into contact with the thrust receiving surfaces 408b1 to 408b3 of the optical member 408, thereby determining the thrust position of the spacer 411.

[0088] (Expanded perspective view before the elastic member 410 is incorporated into the lens holding member 409) Figure 8 is an exploded perspective view of the lens holding member 409 after the optical member 413, spacer 412, optical member 408, and spacer 411 have been assembled, but before the elastic member 410 has been assembled.

[0089] The elastic member 410 is provided with thrust receiving surfaces 410a1 to 410a3 and 410b1 to 410b3.

[0090] 410a1 to 410a3 are in contact with the thrust bearing surfaces 412b1 to b3 of spacer 412, and 410b1 to 410b3 are in contact with the thrust bearing surfaces 411b1 to 411b3 of spacer 411.

[0091] Furthermore, as will be described later, the sealing member 405 and the elastic member 410 come into contact, and the elastic member 410 is compressed.

[0092] Therefore, an elastic force is generated, biasing the optical member 413 toward the lens holding member 409 via the spacer 412, and biasing the optical member 408 toward the lens holding member 409 via the spacer 411.

[0093] Therefore, the optical member 402 is biased towards the lens holding member 403 via the sealing member 405 to stabilize the thrust position of each optical member.

[0094] (Exploded perspective view before the optical element 401 is fixed by the sealing member 404) Figure 9 is an exploded perspective view before the optical element 401 is fixed to the lens holding member 403 by the sealing member 404.

[0095] The sealing member 404 has a double-sided tape configuration with adhesive on both sides, and is sandwiched between the lens holding member 403 and the optical member 401 to seal the gap between the opening 403c of the lens holding member 403 and the optical member 401. In this embodiment, the sealing member 404 is configured with double-sided tape.

[0096] However, if the optical component 401 is a glass lens in which distortion due to the shrinkage of the adhesive does not affect the optical performance, then such a configuration is not necessary, and a configuration in which the entire circumference is bonded and sealed with adhesive or the like is also acceptable.

[0097] (Expanded perspective view before the optical element 402 is assembled into the lens holding member 403) Figure 10 is an exploded perspective view after the optical element 401 has been sealed and fixed to the lens holding member 403, but before the optical element 402 has been assembled.

[0098] The 402b1 to 402b6 provided on the outer circumference of the optical element 402 are radial receiving surfaces that perform radial positioning with respect to the lens optical axis 1000 (Figure 2).

[0099] The optical member 402 is positioned radially so that its optical axis aligns with the optical axis 1000 of the eyepiece by contacting the radial receiving surfaces 403b1 to 403b6 provided on the inner circumference of the lens holding member 403.

[0100] 402a1 to 402a3 are thrust receiving surfaces that position the optical member 402 in the thrust direction with respect to the optical axis 1000 of the eyepiece 16.

[0101] These thrust receiving surfaces 402a1 to 402a3 come into contact with the thrust receiving surfaces 403a1 to 403a3 of the lens holding member 403, thereby determining the thrust position of the optical member 402.

[0102] (Exploded perspective view before sealing with sealing member 405) Figure 11 is an exploded perspective view before the gap between the lens holding member 403 and the optical member 402 is sealed with the sheet-like sealing member 405.

[0103] A flat surface 402c is provided on the outer periphery of the optical element 402, outside the effective optical range, and perpendicular to the optical axis 1000.

[0104] Furthermore, when the optical element 402 is incorporated into the lens holding member 403, a flat portion 403c is provided on the outer periphery of the optical element 402, perpendicular to the optical axis 1000.

[0105] When the optical element 402 is incorporated into the lens holding member 403, the two flat portions 402c and 403c mentioned above are arranged to be at approximately the same height.

[0106] The side of the sealing member 405 facing the optical member 402 has an adhesive coating.

[0107] Therefore, by attaching it without any gaps to both the flat surface 403c of the lens holding member 403 and the flat surface 402c of the optical member 402, which are at approximately the same height, the lens holding member 403 and the optical member 402 are sealed.

[0108] This configuration allows the plastic optical component 402, which is easily deformed by external forces, to be sealed without being subjected to a load that would cause deformation.

[0109] Thus, only the optical element 401 and the second optical element 402 that are in contact with the outside air are made into an optical retaining member 403, separate from the optical retaining member 409.

[0110] This configuration makes it easy to attach the sheet-like sealing member 405 to the flat surfaces 402c and 403c, which are at approximately the same height, when the optical member 402 is incorporated into the lens holding member 403.

[0111] (Expanded perspective view before the optical components 401 and 402 are sealed and fixed to the lens holding member 403 and then assembled.) Figure 12 shows the lens holding member 409 with the optical member 413, spacer 412, optical member 408, spacer 411, and elastic member 410 assembled, and is an exploded perspective view before combining the lens holding member 403 with the optical members 401 and 402 sealed and fixed.

[0112] The position in the radial direction is determined by the positioning pin 409h of the lens holding member 409 and the positioning hole 403d of the lens holding member 403.

[0113] Furthermore, the flat portion 409j of the lens holding member 409 and the flat portion 403e (Figure 11) of the lens holding member 403 come into contact, determining their position in the thrust direction, and the two lens holding members are fixed together by the screw 414.

[0114] At that time, the sealing member 405 and the elastic member 410 come into contact, and the elastic member 410 is compressed, generating an elastic force.

[0115] This biases the optical member 413 toward the lens holding member 409 via the spacer 412, and biases the optical member 408 toward the lens holding member 409 via the spacer 411.

[0116] The optical component 402 is biased towards the lens holding member 403 via the sealing member 405 to stabilize the thrust position of each optical component.

[0117] Furthermore, the elastic member 410 biases the sealing member 405 against both the optical member 402 and the lens holding member 403, resulting in a more robust seal.

[0118] In this embodiment, the optical members 413 and 408 are biased toward the lens holding member 403 using the elastic member 410 via spacers 411 and 412. However, the elastic member 410 may be used to directly contact and bias either the optical member 413 or the optical member 408.

[0119] With the above configuration, the space between optical member 401 and optical member 402 is sealed by a sealing member 404, a lens holding member 403, and a sheet-like sealing member 405. This prevents water vapor from entering from the outside.

[0120] Therefore, the inner surface of the optical element 401 is less likely to become humid, and even if the temperature on the inner surface of the optical element 401 drops due to the influence of the outside air, the amount of water vapor in the sealed space is less likely to exceed the saturation water vapor amount, making fogging less likely.

[0121] Furthermore, the configuration is such that only the space between optical element 401 and optical element 402 is sealed. This makes it possible to reduce the absolute amount of water vapor present in the sealed space.

[0122] As a result, the temperature on the inner surface of the optical component 401 decreases due to the influence of the outside air, and even if the amount of water vapor in the sealed space exceeds the saturation water vapor amount, fogging can be kept to a minimum.

[0123] Furthermore, because the optical element 402 is convex toward the optical element 401 and the optical element 401 has a flat plate shape, when the space between the optical element 401 and the optical element 402 is sealed, the volume can be reduced by having a convex lens fit into the space.

[0124] Furthermore, by making the distance L (shown in Figure 2) between optical elements 401 and 402 near the optical axis 1000 shorter than the thickness t (shown in Figure 2) of optical element 401, the air layer near the optical axis 1000 is reduced, which has the effect of making the central part that the user looks into less likely to fog up during use.

[0125] Furthermore, the optical element 401 in contact with the outside air was made into a flat plate. This makes it less likely for temperature variations to occur in the optical element 401, resulting in a uniformer appearance that is less prone to fogging.

[0126] Furthermore, even if at least one of the optical element 401, which is in contact with the outside air, or the second optical element 402 from the outside is made of plastic, the sheet-like sealing member 405 can be used to seal the lens without putting any load on it.

[0127] Therefore, condensation can be prevented without affecting surface accuracy, resolution, or image distortion.

[0128] The key features of this embodiment are summarized below.

[0129] The first feature is illustrated using Figure 2.

[0130] The optical device comprises an optical system having at least two or more optical members, a first optical member 401 that is in contact with the outside air, and a second optical member 402 located inside the first optical member 401.

[0131] The optical device also includes a first holding member 403 capable of holding the first optical member 401 and the second optical member 402, and a first sealing member 404 that seals the gap between the first optical member 401 and the first holding member 403.

[0132] Furthermore, the optical device includes a second sealing member 405 that seals the gap between the first holding member 403 and the second optical member 402.

[0133] The second optical member 402 has a contact portion 402c on its outer circumference that makes close contact with the second sealing member 405, and the first holding member 403 has a contact portion 403c on its outer circumference that makes close contact with the second sealing member 405.

[0134] The first optical member 401 and the first holding member 403 are sealed by the first sealing member 404, and the space between the first optical member 401 and the second optical member 402 is sealed.

[0135] The second feature is illustrated using Figures 2 and 3.

[0136] The first optical element 401 is characterized by being a flat plate.

[0137] The third feature is illustrated using Figures 2 and 3.

[0138] The second optical element 402 is characterized by being made of plastic.

[0139] The fourth feature is shown using Figure 2.

[0140] The second optical element 402 is characterized by being a lens with a convex shape toward the first optical element 401.

[0141] The fifth feature is illustrated using Figure 2.

[0142] The distance between the first optical member 401 and the second optical member 402 on the optical axis is shorter than the thickness of the first optical member 401.

[0143] The sixth feature is illustrated using Figure 2.

[0144] The first sealing member 404 is characterized by being double-sided tape.

[0145] The seventh feature is shown using Figure 2.

[0146] The first sealing member 404 is characterized by being an adhesive.

[0147] The eighth feature is illustrated using Figures 2 and 9.

[0148] The first sealing member 404 and the second sealing member 405 are characterized in that either one of them also serves as a mask that limits the optical path.

[0149] Figure 3 illustrates the characteristics of the Ninth Symphony.

[0150] Furthermore, it is equipped with an electronic display device 29, The first optical member 401 and the second optical member 402 are characterized in that they constitute a magnifying optical system for observing the electronic display device 29 in a magnified manner.

[0151] Figure 2 illustrates the tenth feature.

[0152] The optical effective range of the first optical member 401 and the second optical member 402 is shorter in the vertical direction than in the horizontal direction.

[0153] Figure 1 illustrates the eleventh feature.

[0154] Furthermore, the system further includes diopter adjustment means 900 for adjusting the diopter of the electronic display device 29, The diopter adjustment means 900 is characterized in that the diopter can be adjusted by moving the position of the electronic display device 29 in the optical axis direction.

[0155] Figure 1 illustrates the twelfth characteristic.

[0156] A key feature is that when the diopter is adjusted by the diopter adjustment means 900, the relative positional relationship between the first optical member 401 and the second optical member 402 remains unchanged.

[0157] Figure 2 illustrates the thirteenth characteristic.

[0158] Furthermore, the device includes a third optical member 408 positioned inside the second optical member 402, a second retaining member 409 for holding the third optical member 408, and a biasing member 410 for biasing the first retaining member 403 to the second retaining member 409.

[0159] The second sealing member 405 and the biasing member 410 come into contact, and the biasing member 410 is compressed, thereby biasing the first holding member 403 toward the second holding member 409 and determining its position in the optical axis direction.

[0160] Figure 2 illustrates the fourteenth characteristic.

[0161] The contact portion of the second optical member 402 is a flat portion 402c that makes close contact with the second sealing member 405.

[0162] The contact portion of the first retaining member 403 is a flat portion 403c that makes close contact with the second sealing member 405.

[0163] Next, we will show combinations of embodiments included in the present invention.

[0164] (Composition 1) An optical system having at least two or more optical elements, comprising a first optical element 401 in contact with the outside air, and a second optical element 402 located inside the first optical element 401, A first holding member 403 capable of holding the first optical member 401 and the second optical member 402, A first sealing member 404 that seals the gap between the first optical member 401 and the first holding member 403, An optical device having a second sealing member 405 that seals the gap between the first holding member 403 and the second optical member 402, The second optical member 402 has a contact portion 402c on its outer circumference that makes close contact with the second sealing member 405, The first retaining member 403 has a contact portion 403c on its outer circumference that makes close contact with the second sealing member 405, The first optical member 401 and the first holding member 403 are sealed by the first sealing member 404. An optical device characterized in that the space between the first optical member 401 and the second optical member 402 is sealed.

[0165] (Configuration 2) The optical apparatus according to configuration 1, characterized in that the first optical member 401 is a flat plate.

[0166] (Composition 3) The optical device according to configuration 1 or 2, characterized in that the second optical member 402 is made of plastic.

[0167] (Composition 4) The optical apparatus according to any one of configurations 1 to 3, characterized in that the second optical member 402 is a lens with a convex shape toward the first optical member 401.

[0168] (Composition 5) The optical apparatus according to any one of configurations 2 to 4, characterized in that the distance between the first optical member 401 and the second optical member 402 on the optical axis is shorter than the thickness of the first optical member 401.

[0169] (Composition 6) The optical device according to any one of configurations 1 to 5, characterized in that the first sealing member 404 is double-sided tape.

[0170] (Composition 7) The optical apparatus according to any one of configurations 1 to 6, characterized in that the first sealing member 404 is an adhesive.

[0171] (Composition 8) The optical apparatus according to any one of configurations 1 to 7, characterized in that either the first sealing member 404 or the second sealing member 405 also serves as a mask for limiting the optical path.

[0172] (Composition 9) Furthermore, it is equipped with an electronic display device 29, The optical device according to any one of configurations 1 to 8, characterized in that the first optical member 401 and the second optical member 402 constitute a magnifying optical system for observing the electronic display device 29 in a magnified manner.

[0173] (Composition 10) The optical apparatus according to any one of configurations 1 to 9, characterized in that the optical effective range of the first optical member 401 and the second optical member 402 is shorter in the vertical direction than in the horizontal direction.

[0174] (Composition 11) Furthermore, the system further includes diopter adjustment means 900 for adjusting the diopter of the electronic display device 29, The optical device according to configuration 9, characterized in that the diopter can be adjusted by moving the position of the electronic display device 29 in the optical axis direction using the diopter adjustment means 900.

[0175] (Composition 12) The optical device according to configuration 11, characterized in that the relative positional relationship between the first optical member 401 and the second optical member 402 does not change when the diopter is adjusted by the diopter adjustment means 900.

[0176] (Composition 13) Furthermore, it includes a third optical member 408 positioned inside the second optical member 402, a second retaining member 409 for holding the third optical member 408, and a biasing member 410 for biasing the first retaining member 403 to the second retaining member 409. The optical apparatus according to any one of configurations 1 to 12, characterized in that the second sealing member 405 and the biasing member 410 come into contact, and the biasing member 410 is compressed, thereby biasing the first holding member 403 toward the second holding member 409 and determining its position in the optical axis direction.

[0177] (Composition 14) The contact portion of the second optical member 402 is a flat portion 402c that makes close contact with the second sealing member 405. The optical apparatus according to any one of configurations 1 to 13, characterized in that the contact portion of the first holding member 403 is a flat portion 403c that tightly contacts the second sealing member 405.

[0178] Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of its gist. [Explanation of symbols]

[0179] 29 EVF Module 401 Optical components 402 Optical components 402c Optical component planar section 403 Lens holding member 403c Retaining member flat section 404 Sealing member 405 Sealing member 408 Optical components 409 Lens holding member 410 Elastic member 411 Spacer 412 Spacer 413 Optical components 900 Diopter adjustment dial

Claims

1. A first optical element that is in contact with the outside air, and a second optical element made of plastic that is the second in the direction of the optical axis from the outside air side, A first holding member that holds the first optical member and the second optical member, A first sealing member that seals the gap between the first optical member and the first holding member, An optical device having a sheet-like second sealing member that seals the gap between the first holding member and the second optical member, The first optical member is held on one side of the first holding member in the optical axis direction, and the second optical member is held on the other side. The first planar portion of the outer periphery of the other side of the first holding member, which is provided on a plane perpendicular to the optical axis, and the second planar portion of the outer periphery of the other side of the second optical member, which is provided on a plane perpendicular to the optical axis, form the same plane. An optical device characterized in that the first flat portion and the second flat portion are in close contact with a flat portion provided on one side of the second sealing member.

2. The optical apparatus according to claim 1, characterized in that the first optical member is a flat plate.

3. The optical apparatus according to claim 1, characterized in that the second optical member is a lens with a convex shape toward the first optical member.

4. The optical apparatus according to claim 2, characterized in that the distance between the first optical member and the second optical member on the optical axis is shorter than the thickness of the first optical member.

5. The optical device according to claim 1, characterized in that the first sealing member is double-sided tape.

6. The optical apparatus according to claim 1, characterized in that the first sealing member is an adhesive.

7. The optical apparatus according to claim 1, characterized in that either the first sealing member or the second sealing member also serves as a mask for limiting the optical path.

8. The contact portion of the second optical member is a flat surface that makes close contact with the second sealing member. The optical device according to claim 1, characterized in that the contact portion of the first holding member is a flat portion that tightly contacts the second sealing member.

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