compact adjustment device for an optical lens of a camera for a Scheimpflug type application

Abstract

The invention relates to an adjustment device (100) for an optical lens (2) of a camera (3), comprising an adjustment device (100) according to the invention, and a method for adjusting said camera. According to the invention, the adjustment device (100) comprises an openwork fixing base (101) and two beveled rings, a first ring (102) of which is rotatably mounted on said base (101) and a second ring (103) of which is rotatably mounted on said first ring (102), said second ring (103) being intended to receive the optical lens (2) of the camera (3). Figure for abstract: Figure 6

Description

Title of the invention: compact adjustment device for an optical lens of a camera for a Scheimpflug type application

[0001] The present invention relates to a device for adjusting an optical lens of a camera for a Scheimpflug type application.

[0002] As a reminder, when an angle is formed between the optical axis of an optical lens of a camera, such as a camera, and the normal to an observation plane, one solution for focusing on the entire inclined plane consists of closing the diaphragm of the optical lens to increase the depth of field. However, the main disadvantage of this diaphragm closure results in a loss of brightness which will have an impact on the quality of the images obtained by the camera, knowing that it is not always possible to compensate for this lack of brightness (specific emissions from flames for example) or at significant financial costs (at the cost of more powerful laser sources for example).

[0003] To overcome this brightness problem, that is to say possibly to be able to work at full aperture while optimizing the depth of the sharpness zone on the observation plane, it is advisable to respect the Scheimpflug principle. This principle states that in an inclined configuration of the optical axis relative to the observation plane, the observation plane, or sharpness plane, passes through the intersection of the sensor plane (image plane) of the camera, and the plane passing through the optical center of the lens and normal to the optical axis. In practice, to place oneself in the conditions for applying the Scheimpflug rule, it is necessary to play on the orientation of the optical lens by creating an angular offset between said optical lens and the sensor plane, so as to obtain an optimal sharpness zone in the observation plane.

[0004] An adjustment device according to the invention is designed to be mounted on a camera such as a camera, and to enable the optical lens of this camera to be oriented in a very large number of different directions in space so as to increase the possible configurations for obtaining a Scheimpflug type correction.

[0005] The adjustment device according to the invention is very compact in order to maintain the nominal optical back focus. This device can provide correction at 2 angles (drift and incidence). Said adjustment device allows working at nominal back focus (without loss of brightness and presence of optical aberrations) and without vignetting. The mount of said adjustment device is solid, allowing it to support heavy optics. Said adjustment device can be used in imaging experiments with access complex optics (large angles between the optical axis and the observation plane). This adjustment device is particularly suitable for the large 24mm x 36mm sensors of certain fast cameras.

[0006] The subject of the invention is a device for adjusting an optical lens of a camera, designed to be mounted in said camera between a sensor of this camera and said optical lens.

[0007] According to the invention, the adjustment device comprises an openwork fixing base which makes it possible to adapt specifically to a front face of the camera, and two beveled rings, a first ring of which is rotatably mounted on said base and a second ring of which is rotatably mounted on said first ring, said second ring being intended to receive the optical lens of the camera. After adjusting the various rotations, the adjustment device can be locked by means of the set screws located on the periphery of the first ring. More precisely, each of the rings is cylindrical in shape, and has a first end lying in a plane which is perpendicular to the axis of revolution of the ring in question, and a second end lying at least partially in an inclined plane which is not perpendicular to said axis of revolution.The first end and the second end of each ring are to be considered along the axis of revolution of each of the two rings. The two rings are mounted on the base so that the first end of the first ring is in contact with said base, and so that the first beveled end of the second ring is located opposite the second beveled end of the first ring.

[0008] Preferably, the base is circular in shape and has a central opening. The adjustment device is mounted in the camera so that the sensor of this camera is located on one side of the base, and the assembly composed of the first ring and the second ring is located on the other side of said base, said sensor being placed inside said camera and the two rings projecting outwards from it. Thanks to the superposition of these two beveled rings, the optical lens of the camera can occupy a multiplicity of positions inclined relative to the normal to a plane in which the sensor would be inscribed, between: - a first extreme position for which the optical objective is aligned along this optical axis and for which the nominal optical draw of the optical objective is perfectly respected, and - a second extreme position for which it is inclined relative to said optical axis with a maximum angular amplitude. Thanks to such an arrangement, the angle between the axis of the sensor of the camera and the optical axis of the lens is adjusted by the rotation of the two beveled rings, the orientation of the angle thus adjusted can be modified by rotating the first beveled ring relative to the base. As a result, it is possible to apply the Scheimpflug principle with the camera on which the adjustment device according to the invention is mounted, with the aim of improving the sharpness of the images obtained with said measuring device, while maintaining the nominal draw and therefore limiting optical aberrations and losses of brightness.

[0009] According to a possible characteristic of the invention, the second ring is in contact with the first ring via their respective beveled faces and pivots on said first ring while remaining in contact with the latter. The beveled base of the first ring is elliptical, the rotation is ensured by a circular recess in the part at the level of the groove of the first ring allowing the insertion of the second ring. In this way, the pivoting of the rings on the base and the positioning of the rings relative to each other is well controlled, without the presence of intermediate parts which could distort their positioning within the adjustment device.

[0010] According to a possible characteristic of the invention, the two rings each have an identical inclined bevel, preferably of 10° allowing a maximum angular variation of 20° of the axis of the optical objective relative to the normal to the plane in which the sensor is inscribed. The presence of such a bevel is generally sufficient to allow the Scheimpflug principle to be applied effectively with the camera on which the adjustment device according to the invention would be mounted.

[0011] According to a possible characteristic of the invention, the adjustment device comprises a third ring intended to receive the optical objective and a fourth ring pivotally mounted on the second ring, the third ring being mounted in translation on the fourth ring, a rotation of the fourth ring on the second ring making it possible to place the translation axis between the third ring and the fourth ring along an axis of greater slope obtained by the position of the first ring and the second ring, the translation movement being intended to move the optical objective to permanently refocus the image on the sensor of the camera.In this way, once the first ring and the second ring have been adjusted to obtain the Scheimpflug effect, namely to be in the conditions of application of the Scheimpflug law, it happens that the image obtained by the camera is offset relative to the optical sensor of said camera; this then results in partial vignetting. The translation of the third ring carrying the optical lens on the fourth ring makes it possible to bring this image back over the entire surface of the optical sensor. As it is also possible that after the adjustment of the first ring and the second ring, the translation axis is not positioned along the axis of greatest slope, the fourth ring to which the third ring is fixed will undergo a preliminary movement of . rotation to bring the translation axis along the axis of greatest slope, before carrying out the translation movement of the third ring on the fourth ring. The presence of the fourth ring which is mounted in rotation on the second ring significantly increases the possibilities of use of an adjustment device according to the invention by allowing the translation movement of the third ring relative to the second ring, to always be oriented along the axis of greatest slope. Preferably, the fourth ring is thin and of small thickness. Advantageously, the thickness of this fourth ring is less than or equal to 3 mm.

[0012] According to a possible characteristic of the invention, the third ring comprises a lower part which is mounted in translation on the fourth ring and an upper part which is mounted on said lower part, the lower part and the upper part each having the shape of a ring and being superimposed on one another. With respect to the fourth ring, the lower part of the third ring can only undergo a translational movement.

[0013] According to a possible characteristic of the invention, the upper part of the third ring has a complementary rotation around its axis of revolution. This complementary rotation of the upper part of the third ring around its axis of revolution makes it possible to rotate the optical lens around the optical axis to align, among other things, any masks located at the rear of the optical lens with the shape and position of the sensor used in the camera.

[0014] According to a possible characteristic of the invention, the upper part of the third ring is intended to receive the optical objective and has fixing means intended to cooperate with complementary fixing means of said optical objective. Once the optical objective is fixed to the upper part of the third ring, it has no possibility of displacement relative to said upper part. Advantageously, the optical objective which is generally of cylindrical shape is inserted into the upper part of the third ring before being fixed thereto. The fixing of the optical objective to the upper part of the third ring can for example be carried out by means of a bayonet type interaction.

[0015] According to a possible characteristic of the invention, the first ring, the second ring, the third ring and the fourth ring are made of metal. Such a material makes it possible to obtain good precision in mounting the rings, without observing any drift in their positioning over time. In addition, rings made of metal offer good mechanical resistance to the weight of the optics and make it possible to make adjustments with greater precision.

[0016] According to a possible characteristic of the invention, the first ring, the second ring, the third ring and the fourth ring are manufactured using a 3D printer. Certain assemblies may prove impossible to produce by machining. conventional due to the specific shape of the parts involved and nested together. Indeed, some parts may require specific shapes that, once manufactured, would prove impossible to include in other parts. 3D metal printing allows parts to be manufactured progressively and simultaneously, and directly in their interaction configuration to obtain a solid adjustment device capable of supporting heavy optics.

[0017] According to a possible characteristic of the invention, following the adjustment of the various rotations and / or translations, the adjustment device is locked by means of the point screws located on the periphery of each of the rings. These point screws facilitate the adjustment of the adjustment device.

[0018] Another subject of the invention is a camera comprising a sensor, an optical lens and an adjustment device according to the invention.

[0019] According to the invention, the base has an external surface on which the first beveled ring and the second beveled ring are mounted, and an internal surface which is parallel to said external surface, and the adjustment device is mounted in said camera such that the first ring, the second ring and the optical lens project towards the outside of the camera and such that the internal surface is located opposite the sensor. The insertion of the adjustment device into the camera must be carried out without having to fundamentally modify the structural characteristics of this camera. The sensor is inside the camera, while the adjustment device projects towards the outside of said camera. The set of rings and the base must allow a passage to be provided allowing an object targeted by the camera to be projected onto the sensor.The adjustment of the position of the rings can be done manually or by means of at least one motor which can for example be of electric source, said motor making it possible for example to move with great precision an endless screw to ensure the translational movement of the rings concerned but also the rotational movement of the rings between them for an automated adjustment of the angle for example.

[0020] According to a possible characteristic of the invention, the camera is delimited by a housing, the base of the adjustment device closing said housing while being in continuity with a wall of said housing. The insertion of the adjustment device into the camera must not hinder the use of this camera. It is therefore carried out naturally, without causing major bulk which could impair the operation of said camera.

[0021] Another subject of the invention is a method for adjusting a camera having an optical lens, a camera and an adjustment device according to the invention, said method comprising the following steps:

[0022] - the adjustment device is mounted on the camera by its specific base,

[0023] - the optical lens is mounted on the adjustment device at the part su upper part of his third ring,

[0024] -the angle between the normal to the plane of the camera sensor and the optical axis of the lens is adjusted by rotating the two beveled rings between them, -the orientation of the angle thus set is modified by the rotation of the first beveled ring relative to the base, - to refocus the image obtained through the optical lens relative to the camera sensor, the optical lens is shifted by the translation of the third ring on the fourth ring, said translational movement being able to be preceded by a rotational movement of the assembly constituted by the third ring and the fourth ring on the second ring, thanks to said fourth ring which is mounted in rotation on said second ring,

[0025] - finally, the orientation along the optical axis of the optical lens is modified thanks to the rotation of the upper part of the third ring on the lower part in order in particular to align the masks of the optical lens in relation to the camera sensor.

[0026] A detailed description of a preferred embodiment of an adjustment device and camera according to the invention is given below, with reference to the following figures:

[0027] [Fig-1] [Fig.l] is a schematic view of a camera explaining the principle of Scheimpflug,

[0028] [Fig.2] [Fig.2] is a perspective view of a camera showing the location of an adjustment device according to the invention,

[0029] [Fig.3] [Fig.3] is a perspective view of an adjustment device according to the invention in a first configuration without tilt angle,

[0030] [Fig.4] [Fig.4] is a perspective view of an adjustment device according to the invention with a maximum tilt angle,

[0031] [Fig.5] [Fig.5] is a perspective view of an adjustment device according to the invention for which the adjustment of the first ring and the second ring to obtain the Scheimpflug effect results in a positioning of the translation axis between the third ring and the fourth ring which does not correspond to the axis of greatest slope,

[0032] [Fig.6] [Fig.6] is a perspective view of the adjustment device of [Fig.5], after rotating the fourth ring to place the translation axis along the axis of greatest slope, the third ring having been translated along the fourth ring, the inclination of said adjustment device.

[0033] When an angle is formed between the optical axis 1 of the optical lens 2 of the camera 3 and the normal 4 to the observation plane 5, a solution to focus on the entire inclined plane consists of closing the diaphragm of the optical objective 2 to increase the depth of field. But a disadvantage linked to this solution is a loss of brightness which can degrade the quality of the images obtained by said camera 3.

[0034] To continue working at full aperture while optimizing the depth of the sharpness zone, it is appropriate to apply the Scheimpflug principle, which is illustrated in [Fig.l]: the observation plane 5 or sharpness plane, passes through the intersection of plane 6 of the sensor or image plane, and plane 7 passing through the optical center of the optical lens 2 and normal to the optical axis 1. In practice, the adjustable parameter is constituted by the orientation of the optical lens 2 to carry out an angular offset relative to the plane 6 of the sensor, so as to place oneself in the Scheimpflug conditions and obtain an optimal sharpness zone. Currently, devices for adjusting the optical lens 2 are inserted on the front face of the cameras 3, so as to obtain the desired angular offset between the plane 6 of the sensor and the plane 7 passing through the center of the optical lens 2 and normal to the optical axis 1 to apply the Scheimpflug principle.However, the adjustment devices available on the market today do not meet the needs of certain applications. Problems are particularly encountered in the presence of large sensors used, for example, in certain high-speed cameras. A significant thickness between the optical lens 2 and the sensor will cause: . -an increase in optical draw with the consequence of a loss of brightness, a modification of magnification, loss of focus at infinity, -the presence of optical aberrations and -the presence of vignetting reflecting a significant decentering of the image formed in relation to the sensor.

[0035] Furthermore, certain current adjustment devices offer a limited choice of possible angular positions for the optical objective 2 by only offering correction with an angle in the horizontal plane, said devices often being bulky.

[0036] An adjustment device 100 according to the invention which is notably illustrated in [Fig.2], is mounted on a camera 3 and makes it possible to easily and precisely move the optical objective 2 to position itself with control in Scheimpflug conditions.

[0037] Referring to Figures 3, 4, 5, 6, an adjustment device 100 according to the invention comprises an openwork fixing base 101, and two beveled rings 102, 103, a first ring 102 of which is rotatably mounted on said base 101, and a second ring 103 of which is rotatably mounted on said first ring 102. Each of the two rings 102, 103 is cylindrical in shape, and has a first end open inscribed in a plane which is perpendicular to the axis of revolution of the ring in question 102, 103, and a second end inscribed in an inclined plane which is not perpendicular to said axis of revolution. In other words, the second end is beveled. The first ring 102 and the second ring 103 are arranged relative to each other in a concentric manner, their axes of revolution merging in a first position, without an angle of inclination as illustrated in [Fig.3]. As a result, the adjustment device can be used when not in the Scheimpflug configuration (cancellation of the angle possible without having to remove the mount). The first ring 102 is mounted in rotation on the base 101 around its axis of revolution, and the second ring 103 is mounted in rotation on the first ring 102 around an axis perpendicular to the beveled surface of the second end.The beveled base of the first ring 102 is elliptical, the rotation being ensured by a circular recess in the part at the level of a groove allowing the insertion of the second ring 103. The two rings 102, 103 are mounted on the base 101 so that the first end of the first ring 102 is in contact with said base 101, and so that the two rings 102 and 103 are in contact via their beveled faces: the second end of the second ring 103 is located opposite the second beveled end of the first ring 102. Preferably, the first ring 102 and the second ring 103 are identical. The adjustment device 100 operates in Scheimpflug configuration with significant optical inclination angles (up to a maximum angle of the order of 20°) relative to the normal to the plane in which the sensor is located.Advantageously, the second beveled end of each ring 102, 103 has an inclination of 10° relative to the plane in which the first end thereof is inscribed. Preferably, markings are visible on the first ring 102 and the second ring 103 to assist in adjusting the rotations of the two rings 102, 103.

[0038] In this way, the second beveled end of the second ring 103 which is rotatably mounted on the first ring 102, can be rotated between a first extreme position as illustrated in [Fig.3] corresponding to a minimum inclination of 0° relative to the normal to the plane in which the sensor is inscribed, and a second extreme position as illustrated in [Fig.4] corresponding to a maximum inclination of 20° relative to the normal to the plane in which the sensor is inscribed. The first extreme position corresponds to a positioning of the two rings 102, 103 for which the two beveled ends are diametrically opposed and compensate each other, the second extreme position corresponding to a positioning of the two rings 102, 103 for which the two second beveled ends are superimposed on each other, their angle of inclination being added.In the order of the adjustment operations, and following the adjustment of the rotation of the second ring 103. on the first ring 102, the adjustment device 100 can be locked by means of the point screws 115 located on the periphery of the first ring 102. After adjusting the rotation of the first ring 102 on the base 101, the adjustment device 100 can be locked by means of the point screws 118 located on the periphery of the first ring 102.

[0039] Referring to Figures 3, 4, 5 and 6, the base 101 which is specific to a model of camera, such as for example a high-speed camera equipped with a large sensor, is circular in shape and has a central opening. This base 101 has a beveled peripheral edge having holes 114 intended to receive fixing screws.

[0040] Referring to Figures 3, 4, 5 and 6, the adjustment device according to the invention comprises a third ring 106a, 106b and a fourth ring 107 mounted in rotation on the second ring 103, said third ring 106a, 106b being mounted in translation on the fourth ring 107 by means of a dovetail device involving a worm screw 110. The third ring 106a, 106b comprises an upper part 106a and a lower part 106b having substantially the same external diameter, each of said two parts 106a, 106b having the shape of a ring. In this way, the third ring results from the superposition of two rings 106a, 106b. The fourth ring 107 is flat and of small thickness, and is inserted between the lower part 106b of the third ring and the second ring 103.This fourth ring 107, which has substantially the same dimensions as those of the second ring 103, is therefore mounted in rotation on said second ring 103 and pivots on the second ring 103 while remaining in contact with the latter. This fourth ring 107 is fixed to the lower part 106b of the third ring 106a, 106b, so that a pivoting of the fourth ring 107 on the second ring 103 causes a simultaneous pivoting in the same direction and with the same amplitude, of said third ring 106a, 106b. This third ring 106a, 106b is superimposed on the second ring 103 by means of the fourth ring 107, so that: . -the upper part 106a represents the highest part of the third ring 106a, 106b. This upper part 106a is intended to receive the optical lens 2. The optical lens 2 is thus placed in the upper part 106a of the third ring 106a, 106b and is then fixed to it by means of a bayonet or quarter-turn type system, - the lower part 106b is in contact with said fourth ring 107. This third ring 106a, 106b has substantially the same internal diameter as that of the second ring 103, and the same external diameter as that of this second ring 103. One of the two elements to be chosen from the lower part 106b of the third ring and the fourth ring 107, has a rib whose cross section is preferably of trapezoidal shape, and the other element to be chosen from the lower part 106b and the fourth ring 107 has a groove whose cross section is preferably of trapezoidal shape. The rib is inserted into the groove and can move in it by means of a worm screw 110, so that this dovetail interaction allows relative sliding between the element 106b, 107 carrying the rib and the other element 106b, 107 carrying the groove. The upper part 106a of the third ring which is intended to receive the optical lens 2 of the camera, is pivotally mounted on the lower part 106b of said third ring.In this way, the optical lens 2 of the camera which is fixed to the upper part 106a of the third ring can rotate along the optical axis to align, among other things, any masks located at the rear of the optical lens 2 with the shape of the sensor used in the camera. After adjusting the rotation of the upper part 106a of the third ring relative to the lower part 106b, the adjustment device 100 can be locked by means of the set screws 117 located on the periphery of the lower part 106b of the third ring.Thanks to the presence of the fourth ring 107 which is pivotally mounted on the second ring 103 and to which the third ring 106a, 106b is fixed, the dovetail device involving a worm screw 110 allowing a translational movement of said third ring 106a, 106b relative to the second ring 103 by means of the fourth ring, can be rotated until the translation axis is aligned with the axis of the greatest slope given by the combination of the 2 beveled rings 102, 103. In other words, regardless of the position of the third ring 106a, 106b relative to the second ring 103 at the end of a first adjustment involving the first ring 102 and the second ring 103, thanks to the possible rotation of the fourth ring 107 on the second ring 103, the translation axis can always be positioned along the line or axis of greater slope in order to refocus the image formed on the center of the sensor.

[0041] Referring to [Fig.2], an adjustment device 100 according to the invention makes it possible to move an optical objective 2 of a camera 3 to place itself in Scheimpflug conditions, said device 100 being mounted in the camera 3 so that: - the base 101 is secured by screwing onto a wall 109 of the camera 3 while being in continuity with this wall 109, that is to say without introducing marked reliefs with it, -the sensor is placed inside the camera 3 while being located on one side of the base 101, and the different rings 102, 103, 106a, 106b, 107, protrude from the other side of said base 101 while extending towards the outside of said camera 3, -the optical lens 2 of the camera is fixed to the upper part 106a of the third ring 106a, 106b.

[0042] The adjustment of the adjustment device 100 to place the optical lens 2 of the camera 3 in a given position in order to apply the Scheimpflug principle, can be carried out either manually by separately adjusting the different rings involved, or in a motorized manner by means of at least one motor embedded in the camera 3 or in addition, said motor being able for example to be an electric motor to drive a worm screw or gears for the rotations.

[0043] Preferably, the adjustment device 100 according to the invention is made of metal, either with the same metal for all the parts involved, namely the base 101 and the different rings 102, 103, 106a, 106b, 107, or from different metals depending on the parts considered.

[0044] Advantageously, the adjustment device 100 according to the invention is manufactured from a metallic or polymer 3D print ensuring adequate mechanical strength of the assembly. This metallic 3D print provides an anti-disengagement assembly of the rings, the edges of the rings being fitted relative to each other. This assembly of the different parts by the metallic 3D print makes this adjustment device 100 much simpler to adjust without the risk of total disassembly of the parts if the rotation locking set screws are loosened too much.

[0045] Schematically, the first ring 102 and the second ring 103 have the function of moving the optical lens 2 of the camera 3 so as to modify the orientation of the optical axis 1 of the camera relative to the normal to the sensor. When this optical lens 2 has reached a significant inclination which is a function of the position of the first ring 102 and the second ring 103, it is possible that the image captured by said optical lens 2 is very offset relative to the center of the sensor. In order for this image to be perfectly centered on the sensor, the optical lens 2 is translated by means of the worm screw 110 incorporated between the lower part 106b of the third ring and the fourth ring 107.This translation movement may be preceded if necessary by a rotation movement of the fourth ring 107 around the second ring 103 to bring the translation axis along the axis of greatest slope obtained by the position of the first ring 102 and the second ring 103. At the end of the adjustment of the different rotations and / or translations, the adjustment device 100 may be locked by means of the set screws 118, 115, 116, 117 located on the periphery of each of the rings 102, 103, 106a, 106b.

[0046] An adjustment device 100 according to the invention is very compact and allows a camera 3 to be used by placing it in Scheimpflug conditions, while maintaining the nominal draw and correcting the vignetting induced at high angles. The image obtained is thus of optimized quality.

[0047] A method for adjusting a camera having an optical lens 2, a camera 3 and an adjustment device 100 according to the invention, said method includes the following steps:

[0048] - the adjustment device 100 is mounted on the camera 3 by its base 101 as as illustrated in [Fig.2],

[0049] - the optical objective 2 is mounted on the adjustment device 100 by being fixed to the part upper 106a of the third ring,

[0050] - the angle between the normal to the plane of the sensor of the camera 3 and the optical axis of the objective 2 is adjusted by rotating the first beveled ring 102 and the second beveled ring 103 as illustrated in Figures 3 and 4,

[0051] - the orientation of the angle thus set is modified by the rotation of the first ring beveled el02 relative to the base 101,

[0052] - to refocus the image obtained through the optical lens 2 on the sensor of the camera 3, the optical lens 2 is shifted by means of a translational movement of the third ring 106a, 106b, on the fourth ring 107 in the direction indicated by the arrow 200 appearing in [Fig.4]. This simple translational movement occurs if, after the adjustment of the first ring 102 and the second ring 103, the translational axis is already oriented along the line of greatest slope as illustrated in Figures 4 and 6. If this is not the case, as illustrated in [Fig.5], the translational movement may be preceded by a rotational movement of the fourth ring 107 to place the translational axis along the axis of greatest slope obtained by the position of the first ring 102 and the second ring 103 as illustrated in [Fig.4],

[0053] - finally, the orientation along the optical axis of the optical objective 2 can be modified thanks to the rotation of the upper part 106a of the third ring relative to the lower part 106b, in particular to align any masks located at the rear of the optical lens 2 relative to the sensor of the camera 3.

Claims

Claims

1. Adjustment device (100) for an optical lens (2) of a camera (3), designed to be mounted in said camera (3) between a sensor of this camera (3) and said optical lens (2), characterized in that it comprises an openwork fixing base (101) which allows it to be adapted specifically to a front face of the camera and two beveled rings, a first ring (102) of which is rotatably mounted on said base (101) and a second ring (103) of which is rotatably mounted on said first ring (102), and in that said second ring (103) is intended to receive the optical lens (2) of the camera (3).

2. Adjustment device (100) according to any one of claims 1, characterized in that the second ring (103) is in contact with the first ring (102) via their respective beveled faces and pivots on said first ring (102) while remaining in contact with the latter.

3. Adjustment device (100) according to any one of claims 1 to 2, characterized in that the two rings (102, 103) each have an identical inclined bevel of 10° allowing a maximum angular variation of 20° of the optical objective (2) relative to the normal to the plane in which the sensor is located.

4. Adjustment device (100) according to any one of claims 1 to 3, characterized in that it comprises a third ring (106a, 106b) intended to receive the optical objective (2) and a fourth ring (107) pivotally mounted on the second ring (103), and in that the third ring (106a, 106b) is mounted in translation on the fourth ring (107), a rotation of the fourth ring (107) on the second ring (103) making it possible to place the translation axis between the third ring (106a, 106b) and the fourth ring (107) along an axis of greater slope obtained by the position of the first ring (102) and the second ring (103), the translation movement being intended to move the optical objective (2) to permanently recenter the image on the sensor of the camera (3).

5. Adjustment device (100) according to claim 4, characterized in that the third ring comprises a lower part (106b) which is mounted in translation on the fourth ring (107) and an upper part (106a) which is mounted on said lower part (106b), and in that the lower part (106b) and the upper part (106a) have each one has the shape of a ring and are superimposed on each other.

6. Adjustment device (100) according to claim 5, characterized in that the upper part (106a) is intended to receive the optical objective (2) and has fixing means intended to cooperate with complementary fixing means of said optical objective (2).

7. Adjustment device (100) according to any one of claims 5 or 6, characterized in that the upper part (106a) of the third ring (106a, 106b) is rotatably mounted on the lower part (106b) of said third ring.

8. Adjusting device (100) according to any one of claims 5 to 7, characterized in that said fourth ring (107) is fixed to the lower part (106b) of the third ring (106a, 106b) by a dovetail device.

9. Adjusting device (100) according to any one of claims 4 to 8, characterized in that the first ring (102), the second ring (103), the third ring (106a, 106b) and the fourth ring (107) are made of metal.

10. Adjusting device (100) according to any one of claims 4 to 9, characterized in that the first ring (102), the second ring (103), the third ring (106a, 106b) and the fourth ring (107) are manufactured by means of a 3D printer.

11. Adjustment device (100) according to any one of claims 1 to 10, characterized in that the adjustment device (100) is locked by means of the set screws (118, 115, 116, 117) located on the periphery of each of the rings (102, (103, 106a, 106b), at the end of the adjustment of the different rotations and / or translations.

12. Camera (3) comprising a sensor, an optical lens (2) and an adjustment device (100) according to any one of claims 1 to 10, characterized in that the base (101) has an external surface on which the first beveled ring (102) and the second beveled ring (103) are mounted, and an internal surface which is parallel to said external surface, and in that the adjustment device (100) is mounted in said camera (3) so that the first ring (102), the second ring (103) and the optical lens (2) project towards the outside of the camera (3) and so that the internal surface is located opposite the sensor.

13. Camera (3) according to claim 11, characterized in that it is delimited by a housing, and in that the base (101) of the adjustment device (100) closes said housing while being in continuity with a wall (109) of said housing.

14. Method for adjusting a camera (3) having an optical lens (2), a camera (3) and an adjustment device (100) according to any one of claims 4 to 9, characterized in that said method comprises the following steps: - the adjustment device (100) is mounted on the camera (3) by its specific base (101), - the optical lens (2) is mounted on the adjustment device (100) at the upper part (106a) of its third ring, - the angle between the normal to the plane of the camera sensor (3) and the optical axis of the lens (2) is adjusted by rotating the two beveled rings (102, 103), - the orientation of the angle thus adjusted is modified by the rotation of the first beveled ring (102) relative to the base (101), - to refocus the image obtained through the optical lens (2) relative to the sensor of the camera (3), the optical lens (2) is shifted by means of the translation of the third ring (106a, 106b) on the fourth ring (107), said translational movement being able to be preceded by a rotational movement of the assembly constituted by the third ring (106a, 106b) and the fourth ring (107) on the second ring (103, thanks to said fourth ring (107) which is mounted in rotation on said second ring (103), - finally, the orientation of the optical lens (2) along the optical axis is modified by rotating the upper part (106a) on the lower part (106b), in particular to align the masks of the optical lens (2) with respect to the camera sensor (3).

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