The aspects and embodiments thereof relate to the field of filter mounts for mounting optical filters in front of a lens of a camera.
In the field of photography, film and videography, it may be required to position an optical filter in front of a lens of a camera. Such a filter may be used to provide different optical effects, such as polarization, colour correction, or diffusion, which diffusion is used to for example flatter skin, raise shadows, and/or create a classic cinematic style.
In order to position such an optical filter in front of the lens of the camera, such that light entering the lens first passes through the filter, a matte box is used. A matte box can act as a filter holder, and can be mounted in front of a lens. In use, a filter may first be placed in a filter tray, and subsequently the filter tray with the filter is slid into a frame of the matte box. Alternatively, a filter may be connected directly to the matte box, for example with one or more spring-loaded clamps.
As an alternative to using a matte box to position an optical filter in front of a lens of a camera, it has been proposed to use single-sided or double-sided adhesive tape to temporarily connect the optical filter directly to a lens.
It is observed that matte boxes can be bulky, and thus add significant volume and/or mass to a camera and lens combination. This bulkiness may hinder the operator of the camera, which is particularly observed when the lens has to be positioned close to an object which is to be photographed or filmed and/or when the camera is used in a confined space such as the interior of a car, as the matte box may protrude a significant distance outward away from the lens towards the object which is to be photographed or filmed. It is further observed that the presence of a matte box may hinder a camera operator when shooting an over the shoulder shot, wherein the matte box may collide with the head of an actor of whom a rear of the head is shot. A matte box can for example be bulky due to the presence of one or more flags attached to the matte box.
It is observed that the method of using adhesive tape to position the optical filter in front of the lens has several disadvantages. For example, this method may have disadvantages in that it may be difficult to properly connect the filter to the lens, it may take a significant amount of time to connect the filter to the lens, especially during busy filming days with a tight schedule, and/or the adhesive tape may leave adhesive residue behind on the lens and/or filter after the filter is removed again from the lens. Furthermore, the connection between the optical filter and the lens may be unstable, and when the adhesive accidentally becomes loosened, the optical filter may fall off the lens and become damaged.
It is an object of the present disclosure to provide for an optical filter mount which allows convenient mounting of an optical filter in front of a camera lens, which preferably at least partially solves one of problems disclosed with known filter mounts or at least provides an alternative way of mounting the optical filter in front of the camera lens.
A first aspect provides an optical filter mount for positioning an optical filter in front of a lens of a camera. The optical filter mount comprises a mounting frame, with a lens connection mechanism for connecting the mounting frame to the lens of the camera. The optical filter mount comprises one or more connection members arranged for connecting the optical filter or the optical filter adapter to the mounting frame, wherein the one or more connection members form at least one loop into which the optical filter or optical filter adapter can be positioned.
It will be understood that in general, also multiple optical filters and/or multiple optical filter adapters can be positioned in front of the lens using the optical filter mount. The multiple optical filters and/or one or more optical filter adapters may for example be stacked one behind the other. In general, an optical filter may for example be rectangular, square, or even round. A rectangular filter may for example have a width of about 10 cm or 4 inches and a height of about 14 cm or 5.65 inches.
By virtue of the optical filter mount according to the first aspect, a compact means of positioning the optical filter or optical filter adapter may be obtained. Because the optical filter or optical filter adapter can be positioned into at least one loop, the optical filter or optical filter adapter can be connected securely to the lens via the mounting frame. Furthermore, positioning the optical filter or optical filter adapter into the at least one loop can be convenient for a user, and may for example require less time than using adhesive tape for connecting the optical filter to the lens.
As an option, the one or more connection members may form at least two loops into which the optical filter or the optical filter adapter can be positioned. As a further option, the one or more connection members may form at least four loops into which the optical filter or the optical filter adapter can be positioned. It will be understood that although a single loop may be sufficient for connecting the optical filter or optical filter adapter to the mounting frame, multiple loops may allow for an even more secure connection.
A loop may be generally defined as a section of a connection member which is curved. In particular, a loop may be a closed loop or a partially open loop. When the loop is a partially open loop, a closed loop shape may be formed by the partially open loop formed by a connection member together with another part of the filter mount, such as the mounting frame.
When an optical filter or an optical filter adapter is positioned into a loop, said loop may hold the optical filter or optical filter adapter in place. In general, the one or more connection members are directly or indirectly connected to the mounting frame. As such, when an optical filter or an optical filter adapter is positioned into a loop, said loop may hold the optical filter or optical filter adapter in place relative to the mounting frame, and thus in use relative to a lens to which the mounting frame is connected. Preferably, and in general, the connection between the mounting frame and the lens is a substantially rigid connection.
When the filter mount comprises at least two connection members, each connection member may form at least one loop. For example, the filter mount may comprise two connection members, both of which form two loops. More in general, at least one of the connection members may form at least two loops.
When the filter mount comprises at least two loops, these loops may be positioned on opposite sides of the mounting frame. This may allow for a more secure positioning of the optical filter or optical filter adapter relative to the mounting frame.
At least one or even all of the one or more connection members may be or comprise an elongated member, arranged to be resiliently elongated, such as an elastic band, elastic strap, elastic belt, or elastic ribbon. In particular, at least a part or parts of a connection member forming a loop may be or comprise an elongated member, arranged to be resiliently elongated, such as an elastic band. By virtue of resiliently elongating at least part of a loop of a connection member, an optical filter or optical filter adapter positioned into said loop may be clamped, pushed, pressed or pulled towards or against the mounting frame, which may allow for a more secure positioning of the optical filter or optical filter adapter relative to the mounting frame.
In general, an elongated member, such as an elastic band, may comprise one or more elongated strands, of which at least part may be elastically elongated in use. An elongated member may comprise elastic material such as rubber, any elastomer, or any other material which is elastically deformable, preferably by a single camera operator, even more preferably using one hand. Furthermore in general, an elongated member may be elastically strechted out more than 10% of its unstretched length, more than 20%, more than 50%, or even more than 100%.
As a particular option, a loop may be internally disconnected and connected again. As such, a loop may be disconnected to allow positioning of the optical filter or optical filter adapter, and reconnected to fix the optical filter or optical filter adapter into the loop. For example, the loop may be opened and closed alike a belt.
In particular when a connection member is or comprises an elongated member, a first end of a connection members may be connected to the mounting frame, and a second end of the one of the connection members is may be a free end. A free end of the connection member may be protruding relative to the filter mount, and when the connection member is at least partially resilient or flexible, the free end may dangle or hang away from the filter mount.
As a particular option, embodiments of the optical filter mount may comprise one or more clamps with which one or more free ends may be connected to the optical filter mount, for example to the mounting frame. This may prevent the one or more free ends from dangling freely, and for example getting caught in a focus motor, or hinderingly colliding with an optical filter held by the optical filter mount—which may cause undesired sounds.
To allow one or more loops to be changed in shape, for example tightened or loosened, embodiment of the filter mounts may comprise a tightening mechanism for tightening at least one of the loops. The at least one of the loops may for example be tightened after an optical filter or optical filter adapter is positioned into said loop, for securing the optical filter or optical filter adapter better to the mounting frame.
As an option, when a connection member comprises a free end, the tightening mechanism may comprise a clamp, such as a wedge shaped slit, into which the free end of the connection member can be clamped. This clamping may prevent loosening of one or more loops formed by said connection member.
For example in order to protect part of at least one of the connection members, to prevent or reduce contact with at least one of the connection members, and/or to provide for a more compact filter mount, part of at least one of the connection members may extend through the mounting frame.
The mounting frame may comprise an open ring frame, and the lens connection mechanism may be arranged for closing the open ring frame, such that the open ring frame can be clamped onto a lens.
In general, a lens has a generally cylindrically shaped lens body. An outer diameter—also known as a front diameter—of such a lens body may typically be between 80 mm and 120 mm, for example 87 mm, 95 mm, 110 mm, 114 mm, 160 mm, or any other value. As such, an inner diameter of the open ring frame may generally correspond to one of these diameters.
A step down ring may be positioned between the lens body and the mounting frame, which step down ring has an outer diameter corresponding to an inner diameter of the mounting frame, and an inner diameter corresponding to an outer diameter of the lens body. One or more of such step down rings may be provided in a set of parts, which set of parts also comprises an embodiment of an optical filter mount.
A second aspect provides an optical filter mount assembly, comprising any optical filter mount according to the first aspect, and claims and an optical filter or an optical filter adapter, wherein the optical filter or the optical filter adapter is positioned into at least one loop of the optical filter mount.
A width and/or a height of the optical filter mount assembly may be essentially determined by a width and/or a height of the optical filter or the optical filter adapter. As such, in a compact manner, an optical filter or an optical filter adapter can be mounted to a lens by virtue of the optical filter mount of the first aspect.
In general, it is observed that it may be difficult to position a round or generally non-cuboid optical filter into one or more loops of an optical filter mount. A third aspect provides an optical filter adapter, in particular suitable for use in an assembly according to the second aspect. The optical filter adapter comprises an adapter frame arranged for accommodating a non-cuboid optical filter, such as a round optical filter, which adapter frame is arranged to be positioned inside at least one loop of an optical filter mount, in particular an optical filter mount according to the first aspect.
It will be understood that in the present disclosure, the term optical filter also encompasses diopters and split diopters, which may be generally cylindrically shaped or even shaped as part of a cylinder.
The adapter frame may be generally cuboid-shaped. Additionally or alternatively, the optical filter adapter may comprise at least one hook arranged to be positioned into a loop of an optical filter mount. The loop may wrap around the hook, thereby generally fixing a position of the adapter frame relative to the mounting frame of the optical filter mount.
A fourth aspect provides an alternative optical filter adapter for use in an assembly according to the second aspect. The optical filter adapter comprises an adapter frame arranged for accommodating an optical filter, and further comprises an aperture through the adapter frame, and one or more light-blocking elements adjacent to the aperture, in particular surrounding the aperture. The one or more light-blocking elements may in use prevent light from entering the optical filter from the rear side of the optical filter, which light may reflect through the optical filter into the lens. This reflecting may in general be undesired.
A fifth aspect provides a lens assembly for use with a camera, comprising a lens, and an optical filter mount according to the first aspect or an optical filter mount assembly according to the second aspect, wherein the optical filter mount or optical filter mount assembly is positioned in front of the lens, and light can pass through the optical filter mount or optical filter mount assembly into the lens.
A sixth aspect provides a camera assembly, comprising a camera and a lens assembly according to the fifth aspect. The camera may be a camera for taking photos and/or shooting video, analogue or digital.
A seventh aspect provides a method of mounting an optical filter or an optical filter adapter to a lens of a camera. The method comprises steps of connecting a mounting frame of an optical filter mount to the lens of the camera, and positioning the optical filter or the optical filter adapter between the mounting frame and at least one loop of the optical filter mount.
By virtue of the method according to the seventh aspect, a method may be obtained with which the one or more optical filters and/or optical filter adapters can be conveniently positioned and held in front of the lens of the camera. The method may be quicker than a known method, and/or may provide for a more secure connection between the one or more optical filters or optical filter adapters and the lens. Additionally, or alternatively, the method may result in a more compact and/or less bulky and/or lighter lens assembly.
In embodiments of the method, the one or more optical filters and/or one or more optical filter adapters are pressed against the mounting frame by the at least one loop being elastically deformed. Being pressed against the mounting frame may further secure a position of the one or more optical filters and/or one or more optical filter adapters relative to the mounting frame, and thus relative to the lens.
For example to position the one or more optical filters and/or one or more optical filter adapters in a specific orientation relative to the lens, and/or to further secure a connection between the one or more optical filters and/or one or more optical filter adapters, embodiments of the method may comprise tightening the at least one loop of the optical filter mount, in particular after positioning the one or more optical filters and/or one or more optical filter adapters between the mounting frame and said at least one loop.
It will be understood that different options disclosed in conjunction with a single aspect may be generally applied in any combination in embodiments of said aspect. Furthermore, different options disclosed in conjunction with one of the aspects may be readily applied to embodiments of another of the aspects, in any combination, where applicable.
In the figures,
The mounting frame 106 is arranged to be clamped onto a cylindrical lens 200, and as such comprises a generally circular aperture 101. This circular aperture 101 together with the cylindrical lens allows the optical filter mount 102 to be attached to the lens 200 in several orientations. This in turn allows an optical filter to be positioned in e.g. a portrait-or landscape mode if required. Furthermore, the aperture 101 through the mounting frame 106 allows light to pass through the mounting frame 106, into the lens 200.
For clamping the mounting frame 106 onto the cylindrical lens 200, a lens connection mechanism 108 may be provided. In the embodiment of
In the example of
Although throughout the figures, only a single optical filter 104 is depicted to be held by the optical filter mount 102, it will be understood that also multiple optical filters can be held simultaneously by an optical filter mount 102, for example when the multiple optical filters are stacked behind one another. As such, light can pass through these multiple optical filters before entering the lens.
In the particular embodiment of
The loops 114 are generally formed by one or more connection members. In the particular embodiment of
The loops 114″ and 114″″ can be tightened by pulling on a free end 113″ of the connection member 112″ forming said loops. In order to hold a section of the connection member 112″ between a fixed end 115″ thereof and the free end 113″ in place, an optional tightening mechanism 122 is provided. The fixed end 115″ is for example visible in
In the embodiment of
Because the tightening mechanism or tightening mechanisms 122 allow for the size of one or more of the loops 114′, 114″, 114′″, 114″″″ to be adjusted, a position of the filter 104 relative to the mounting frame 106, and in use relative to the lens 200, may be adjusted by loosening or tightening one or more of the connection members. Such positioning may be preferred when different parts of the optical filter provide a different effect, such as a gradually changing colour filter.
As an option, for example depicted in
As a further option, for example shown in
It may be preferred to in use clamp the optical filter 104 or optical filter adapter 300 against the mounting frame 106—as shown in
The optical filter adapter 300 comprises an adapter frame 302, which in this embodiment is a generally round adapter frame 302. When the adapter frame 302 is generally round, a compact lens assembly 204 may be obtained. To positioned the optical filter adapter 300 into one or more loops 114 of the optical filter mount 102, the adapter frame 302 comprise one or more hooks 304. The number of hooks 304 is generally equal to or larger than the number of loops 114. In detail D, it is shown that the hook 304′ is securely positioned into the loop 114′.
As an option, the adapter 300 comprises one or more light-blocking elements 306, arranged to prevent light from entering the optical filter 104 from the rear side of the optical filter 104. In the embodiment of
In the description above, it will be understood that when an element is referred to as being connect to another element, the element is either directly connected to the other element, or intervening elements may also be present. Also, it will be understood that the values given in the description above, are given by way of example and that other values may be possible and/or may be strived for.
It is to be noted that the figures are only schematic representations of embodiments that are given by way of non-limiting examples. For the purpose of clarity and a concise description, features are described herein as part of the same or separate embodiments, however, it will be appreciated that the scope of the disclosure may include embodiments having combinations of all or some of the features described. The word ‘comprising’ does not exclude the presence of other features or steps. Furthermore, the words ‘a’ and ‘an’ shall not be construed as limited to ‘only one’, but instead are used to mean ‘at least one’, and do not exclude a plurality.
Filing Document | Filing Date | Country | Kind |
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PCT/EP2022/058257 | 3/29/2022 | WO |