Patent Description:
Some substrates, in particular optical substrates, such as for instance spectacle lenses, are often subject to a coating process during their manufacturing process. In some cases, for instance, an anti-reflection coating may be applied to substrates. For the coating process, the substrates may be mounted on a calotte-shaped substrate holder, which is then inserted into a coating device to arrange the substrates at a predetermined position and in a predetermined orientation with respect to a particle source in the coating device. Examples for a coating device and a calotte-shaped substrate holder are described for instance in <CIT> and <CIT>.

Prior to the actual coating process the substrates may require a cleaning treatment to remove possible dust and other contaminants present on the substrates mounted at the calotte-shaped substrate holder. Conventional devices for cleaning ophthalmic components are described in <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, and <CIT>. These devices, however, are not suitable for cleaning substrate mounted on a calotte-shaped substrate holder. Therefore, the cleaning process is conventionally carried out in a manual process including removing the substrates one after another from their respective mounting slots on the substrate holder by hand, applying a cleaning process to the substrates, and replacing the substrates by hand at their original mounting slots, which is considered as closest prior art.

This requires a significant time effort for the cleaning process and bears a significant risk of swapping different substrates by unintentionally replacing them on a different mounting slot as the original mounting slot.

<CIT> describes a cleaning apparatus according to the preamble of claim <NUM>, with a cleaning nozzle and a sucking nozzle.

<CIT> describes a cleaning station for an optical element with a cleaning nozzle and a drying nozzle.

It is thus desirable to provide a method and a device overcoming the disadvantages of the conventional cleaning process. Hence, it is the objective technical problem to provide a method and a device for cleaning the substrates requiring a lower time effort and bearing a lower risk of swapping the substrates.

This problem is solved by a cleaning device according to claim <NUM>, a system for cleaning and coating substrates according to claim <NUM>, and a method having the features of the respective independent claim <NUM>.

Optional embodiments are provided in the dependent claims and the description. In a first aspect a cleaning device adapted for cleaning substrates for spectacle lenses mounted on a calotte-shaped substrate holder is provided, wherein the substrate holder is rotatable in an azimuthal direction around a central axis of the calotte-shaped substrate holder. The cleaning device comprises a first cleaning arm having one or more ejection nozzles and one or more suction nozzles arranged at the first cleaning arm. The first cleaning arm has an arc-shape with a radius of curvature in the range from <NUM>,<NUM> to <NUM> and a length in an altitudinal direction in the range from <NUM>,<NUM> to <NUM>.

In another aspect, a system for cleaning and coating substrates for spectacle lenses is provided. The system comprises a calotte-shaped substrate holder suitable for holding the substrate during a cleaning and coating process. The system is characterized in that it further comprises a cleaning device according to the disclosure.

In yet another aspect, a method for cleaning multiple substrates for spectacle lenses is provided. The method comprises mounting the substrates at mounting slots on a calotte-shaped substrate holder, wherein the mounting slots are arranged on the calotte-shaped substrate holder in one or more rows extending in a concentric manner around a central axis of the calotte-shaped substrate holder. The method further comprises arranging an arc-shaped first cleaning arm of a cleaning device over or underneath the calotte-shaped substrate holder such that the arc-shaped first cleaning arm of the cleaning device extends in an altitudinal direction of the calotte-shaped substrate holder over at least some of the rows of mounting slots. The first cleaning arm has an arc-shape with a radius of curvature in the range from <NUM>,<NUM> to <NUM> and a length in an altitudinal direction in the range from <NUM>,<NUM> to <NUM>. In addition, the method comprises cleaning the substrates by ejecting a cleaning fluid through one or more ejection nozzles provided at the first cleaning arm onto the substrate holder and sucking at least a part of the ejected cleaning fluid into one or more suction nozzles provided at the first cleaning arm and providing a rotational movement of the calotte-shaped substrate holder in an azimuthal direction around the central axis with respect to the first cleaning arm.

In yet another aspect, a method being suitable for manufacturing a spectacle lens from a substrate for a spectacle lens is provided. The method is characterized in that it includes a step of cleaning the substrate for the spectacle lens using an above-disclosed method for cleaning multiple substrates for spectacle lenses.

A substrate for a spectacle lens may be an optical substrate for manufacturing a spectacle lens from the substrate. The substrate may have suitable dimensions for manufacturing one spectacle lens from one substrate. The substrate may form a precursor for an optical product. Alternatively, the substrate may be an (uncut) almost finished optical product which will be finished after completion of the coating process. The substrate may be a spectacle lens blank, a semi-finished spectacle lens product or a finished spectacle lens product and may in particular meet requirements specified in EN ISO <NUM>:<NUM>. "Multiple substrates for spectacle lenses" may mean multiple substrates, wherein each substrate is intended for manufacturing one spectacle lens based on the respective substrate. Throughout the disclosure, the term "substrate" may in general relate to a substrate for a spectacle lens unless explicitly specified otherwise.

Cleaning a substrate may relate to a treatment including removing contaminants and/or moisture and/or any other undesired objects from the substrate which, if not removed, may compromise the coating result. The cleaning process may include subjecting the substrates to a stream of a cleaning fluid to remove such contaminants, wherein the cleaning fluid may comprise a gaseous fluid and/or a liquid fluid. The cleaning fluid may in particular comprise or consist of air and/or or nitrogen. The cleaning fluid may be ejected through one or more ejection nozzles onto the substrate and may be collected by one or more suction nozzles after being in contact with at least one surface of the substrates.

The suction nozzles and the ejection nozzles may be connected with suitable hosing and/or tubing for supplying the cleaning fluid and/or the vacuum to the suction nozzles and/or the ejection nozzles. The tubing and/or hosing and/or connected valves may be attached at the first cleaning arm and/or the second cleaning arm.

The calotte-shaped substrate holder may be simply referred to as substrate holder. The substrate holder being calotte-shaped means that the shape of the substrate holder follows the shape of a calotte. Hence, the substrate holder may be domed, wherein the dome may have the shape of a half sphere or any other portion of a sphere having the shape of a spherical cap or spherical dome. The calotte-shaped substrate holder may have the appearance of a spherical cap but may deviate from the strict mathematical shape of a spherical cap. The calotte-shaped substrate holder may be rotationally symmetric around the central axis, wherein the central axis may form a central axis of a sphere defining the calotte or spherical cap describing the shape of the substrate holder. The calotte-shape of the substrate holder has a radius of curvature in the range from <NUM>,<NUM> to <NUM> and in particular a radius of curvature in the range from <NUM>,<NUM> to <NUM>, i.e., the sphere describing the shape of the calotte holder may have a radius of curvature in the range from <NUM>,<NUM> to <NUM> and in particular a radius of curvature in the range from <NUM>,<NUM> to <NUM>,<NUM> or <NUM>,<NUM> to <NUM>,<NUM>. In case the radius of curvature varies for different altitudinal positions of the calotte-shaped, the radius of curvature may be in the specified range at any position. In other words, any radius of curvature which the calotte-shaped substrate holder exhibits may be well in the specified range. The azimuthal direction and the altitudinal direction may relate to a horizontal coordinate system. The azimuthal direction, altitudinal direction and radial direction used throughout this disclosure may correspond to this sphere describing the shape of the calotte-shaped substrate holder, wherein the azimuthal direction and the altitudinal direction extend on the surface of such sphere and the radial direction extends perpendicular to the surface of such sphere and, hence, towards the center of said sphere. The altitudinal direction of the substrate holder may correspond to the altitudinal direction of the cleaning arm(s). A rotational movement of the substrate holder around its central axis may be provided by a motor unit rotating the calotte-shaped substrate holder around its central axis. The calotte-shaped substrate holder may comprise several parts, such as four segments, which may together form the calotte-shaped substrate holder.

The arc shape of the first and/or second cleaning arm may relate to a spherical arc shape, i.e., the shape of the first and/or second cleaning arm may extend according to an arc forming a part of a surface of a mathematical sphere. The sphere may correspond to the sphere describing the shape of the calotte-shaped substrate holder or may have a larger or smaller radius of curvature. The arc shape may have the appearance of a sphere but may deviate from the strict mathematical shape of a spherical cap. Accordingly, the first cleaning arm has a circular arc-shape. The radius of curvature of the arc-shape of the first cleaning arm and/or second cleaning arm may be identical to the radius of curvature of the calotte-shaped substrate holder or may deviate by not more than <NUM>% and optionally not more <NUM>% from the radius of curvature of the calotte-shaped substrate holder. However, the calotte-shaped substrate holder and/or the first and/or second cleaning arm may have a shape deviating from a spherical shape. In particular, a radius of curvature may vary along the altitudinal position of the calotte-shaped substrate holder and/or along the altitudinal position of the first and/or second cleaning arm. The radius of curvature may decrease for lower altitudinal positions of the calotte-shaped substrate holder and/or the first and/or second cleaning arm, respectively. However, the calotte-shaped substrate holder and/or the first and/or second cleaning arm may be adapted such that at any altitudinal position of the calotte-shaped substrate holder and/or of the first and/or second cleaning arm the radius of curvature is in a range from <NUM>,<NUM> to <NUM>.

Arranging the first cleaning arm over the calotte-shaped substrate holder means that the first cleaning arm is arranged adjacent to the outer surface of the calotte-shaped substrate holder, when the calotte-shaped substrate holder is arranged such that the opening of the calotte-shaped substrate holder is oriented in a downward direction. This may correspond to the typical orientation of the calotte-shaped substrate holder for the intended use of coating the substrates mounted to the calotte-shaped substrate holder. However, in principle other orientations of the calotte-shaped substrate holder are possible. Likewise, arranging the first cleaning arm underneath the calotte-shaped substrate holder means that the first cleaning arm is arranged adjacent to the inner surface of the calotte-shaped substrate holder, when the calotte-shaped substrate holder is arranged such that the opening of the calotte-shaped substrate holder is oriented in a downward direction.

Mounting slots are such slots formed in the calotte-shaped substrate holder which are adapted to receive a substrate in a manner to expose at least one surface of the substrate for the coating process. Each of the mounting slots may comprise a hole in the calotte-shaped substrate holder on which a substrate may be placed, such that the coating may be applied to the surface through the hole in the whole in the substrate holder. The hole of the mounting slot may be adapted to support the substrate at the edge or rim of the substrate while exposing a central region of the substrate to be accessible for the coating process.

The disclosure provides the advantage that the cleaning process for cleaning the substrates prior to a coating process may be carried out in an at least partly automated manner. This may allow reducing the required time effort and the manual labor for cleaning the substrates and, hence, reduce the costs for cleaning and coating process. Moreover, the disclosure may provide the advantage that multiple substrates may be cleaned simultaneously and, hence, the required time for the cleaning process may be further reduced.

Furthermore, the disclosure provides the advantage that the cleaning process may be carried out at least partly while the substrates are mounted in the mounting slots. In other words, the cleaning process may be carried out at least partly without the need of removing the substrates from the mounting slots. This may reduce the risk of unintentionally swapping the substrates during the cleaning process and, hence, may allow reducing a reject of substrates during the manufacturing process including the cleaning and a coating process.

In addition, the disclosure may provide the advantage that the cleaning process may be carried out while the substrates are mounted in a manner ready for a possible subsequent coating process. Hence, the time between the cleaning process and the subsequent coating process can be reduced, which may reduce the risk of the cleaned substrates being subject of further contaminations between the cleaning process and the coating process. Moreover, the cleaning process may optionally be carried out at least partly within the coating device, i.e., while the calotte-shaped substrate holder is arranged inside a coating device, in which the subsequent coating process may be carried out. This may render any movement of the calotte-shaped substrate holder with the substrates mounted thereto after the cleaning process obsolete. Instead, it may allow commencing the coating process right after the cleaning process and by this to minimize the risk of any further contaminations affecting the substrates after the cleaning process.

At least one of the one or more ejection nozzles may be movable in an altitudinal direction along the first cleaning arm. This may allow moving the one or more ejection nozzles to different altitudinal positions of the first cleaning arm and correspondingly to different altitudinal positions of the calotte-shaped substrate holder. Combined with several full rotations of the substrate-holder around the central axis, all mounting slots may be addressed by the one or more ejection nozzles even if only one or few mounting slots are address in each position of the one or more movable ejection nozzles and each rotatory position of the substrate holder. In other words, this may allow subsequently covering a large area of the calotte-shaped substrate holder by providing only one or more ejection nozzles covering a small part of the substrate holder. The same may apply to the suction nozzles. , it may be sufficient to provide one or more ejection nozzles being movable in an altitudinal direction along the first cleaning arm. The movements of the one or more ejection nozzles and the one or more movable suction nozzles may be synchronized. Accordingly, the method for cleaning multiple substrates may further comprise moving at least one of the one or more ejection nozzles along the altitudinal direction while providing a rotational movement of the calotte-shaped substrate holder in the azimuthal direction around the central axis.

The one or more ejection nozzles may be directed in a radial direction with respect to the first cleaning arm. In particular, the ejection nozzles may be directed to that side of the cleaning arm, at which the substrates are arranged during a cleaning process. The ejection nozzles and/or suction nozzles may be oriented at an angle of about <NUM>° with respect to the surface of the substrates, which provide a suitable stream of cleaning fluid over the substrates from the ejection nozzles to the suction nozzles. In case a cleaning arm is arranged over the calotte-shaped substrate holder, the ejection nozzles may be directed in a radially inward direction. If the cleaning arm is directed underneath the calotte-shaped substrate holder, the ejection nozzles may be directed in a radially outward direction. The cleaning arm may be arranged at a predetermined position and orientation with respect to the calotte-shaped substrate holder. The cleaning arm may be adapted such that the one or more movable ejection nozzles may be oriented in a radial direction or in a direction having a predetermine angle with respect to the substrates in any altitudinal position along the cleaning arm. However, the one or more movable ejection nozzles may be adapted to have a variable orientation, which may allow adjusting the orientation of the one or more ejection nozzles to the mounting slots or substrates to be addressed. Likewise, the one or more suction nozzles may be directed in a radial direction and/or may be adapted to have a variable position. The orientation of the one or more ejection nozzles and the one or more suction nozzles may be chosen in dependence on a distance between the one or more ejection nozzles and the one or more suction nozzles.

According to some embodiments, the ejection nozzles and/or the suction nozzles may be oriented such as to have an angle of <NUM>° with respect to the surface of the substrates, to which they are directed.

The one or more ejection nozzles may comprise multiple ejection nozzles distributed in the altitudinal direction on the cleaning arm. The multiple ejection nozzles may be provided such that a fluid stream ejected by the multiple ejection nozzles covers the entire section of the calotte-shaped substrate holder covered by the respective cleaning arm. This may allow covering multiple rows of mounting slots by the stream of cleaning fluid ejected through the multiple ejection nozzles and may, thus, render a movement of one or more ejection nozzles obsolete.

The cleaning device may further comprise a second cleaning arm having one or more ejection nozzles and one or more suction nozzles arranged at the second cleaning arm. The second cleaning arm may have an arc-shape with a radius of curvature in the range from <NUM>,<NUM> to <NUM> and a length in an altitudinal direction in the range from <NUM>,<NUM> to <NUM>. The second cleaning arm may be adapted in an identical or similar manner to the first cleaning arm. However, the orientation or direction of the ejection nozzle(s) and/or the suction nozzle(s) may be different as compared to the first cleaning arm in order to direct the ejection nozzle(s) and suction nozzle(s) to the calotte-shaped substrate holder when arranged at the opposite side of the calotte-shaped substrate holder as compared to the first substrate holder. In general, all features and properties described with respect to the first cleaning arm may apply also to the second cleaning arm and vice versa. Moreover, disclosure referring to a cleaning arm in general may apply to the first cleaning arm and the second cleaning arm in the same manner.

The first cleaning arm and the second cleaning arm may be arranged parallel to each other and spaced apart from each other in a vertical direction. This may allow arranging the calotte-shaped substrate holder in-between the first and second cleaning arm, such that the inner surface of the calotte-shaped substrate holder may be exposed to the second cleaning arm and the outer surface of the calotte-shaped substrate holder may be exposed to the first cleaning arm or vice versa. In other words, the first and second cleaning arm may be adapted and arranged to at least partly enclose the cross-section of the sheath wall of the calotte-shaped substrate holder. Accordingly, the ejection nozzles of the first cleaning arm and the ejection nozzles of the second cleaning arm may be at least partly directed towards each other. This may allow simultaneously cleaning a front surface and a back surface of the substrate.

The vertical spacing between the first cleaning arm and the second cleaning arm may be in a range from <NUM>,<NUM> to <NUM>,<NUM> and optionally from <NUM>,<NUM> to <NUM>,<NUM>. Optionally the vertical spacing between the first cleaning arm and the second cleaning arm may be adjustable. This may facilitate arranging the calotte-shaped substrate holder between the cleaning arms. Alternatively or additionally, the vertical spacing between the first cleaning arm and the second cleaning arm may be set such that a distance between the first cleaning arm and a surface of a substrate mounted on the calotte-shaped substrate holder facing the first cleaning arm is in a predetermined range, such as from <NUM>,<NUM> to <NUM>,<NUM>. This may leave sufficient space for arranging the calotte-shaped substrate holder between the first and second cleaning arm and may allow a distance between the cleaning arms and the substrates mounted in the mounting slots of the calotte-shaped substrate holders sufficiently small to achieve a suitable stream of cleaning fluid from the ejection nozzles to clean the substrates.

In the above-disclosed method, providing the rotational movement of the calotte-shaped substrate holder in the azimuthal direction around the central axis with respect to the first cleaning arm may comprise rotating the calotte-shaped substrate holder by at least <NUM>° around the central axis. This may allow applying a stream of cleaning fluid ejected through the ejection nozzles in the first and/or second cleaning arm along an altitudinal direction of the calotte-shaped substrate holder over the entire surface of the calotte-shaped substrate holder. Hence, although the ejection nozzles may be arranged solely at the cleaning arms covering only a small portion of the entire calotte-shaped substrate holder, the entire calotte-shaped substrate holder and all mounting slots provided therein in one or more rows extending along concentrical circles at the calotte-shaped substrate holder may be subjected to the cleaning process.

The arc-shaped first cleaning arm of the cleaning device may be arranged over the calotte-shaped substrate holder. In this case, the method may further comprise arranging an arc-shaped second cleaning arm of the cleaning device underneath the calotte-shaped substrate holder such that the arc-shaped second cleaning arm of the cleaning device extends in the altitudinal direction of the calotte-shaped substrate holder over at least some of the rows of mounting slots. Accordingly, the step of cleaning the substrates may further comprise ejecting a cleaning fluid through one or more ejection nozzles provided at the second cleaning arm onto the substrate holder and sucking at least a part of the ejected cleaning fluid into one or more suction nozzles provided at the second cleaning arm and providing a rotational movement of the calotte-shaped substrate holder in an azimuthal direction around the central axis with respect to the second cleaning arm. This may allow simultaneously cleaning an upper surface and a lower surface of the substrates by applying the cleaning fluids from one side via the first cleaning arm and from the other side via the second cleaning arm. This may render an additional step for flipping the substrates obsolete and, hence, may reduce the required time and costs for the cleaning process. Moreover, a risk of contaminating or unintentionally swapping the substrates in a flipping process can be avoided or reduced. However, according to other embodiments the method may further comprise a step of flipping all or some of the substrates mounted to the substrate holder. The flipping may be carried out by hand or in an at least partly automated manner. The flipping process may optionally be carried out using a magnetic force. A flipping step may be advantageous for such embodiments of cleaning devices, which do not offer simultaneously cleaning the substrates from both sides.

The method may comprise arranging the calotte-shaped substrate holder in a coating device and the step of arranging the first arc-shaped second cleaning arm of the cleaning device over or underneath the calotte-shaped substrate may comprise arranging the cleaning device adjacent to the coating device. Moreover, the method may further comprise removing the cleaning device from the coating device after cleaning the substrates. This allows carrying out the cleaning process while the calotte-shaped substrate holder is arranged at least partly inside a coating device. This may render a rearrangement of the substrate holder between the completion of the cleaning process and the commencement of the coating process obsolete and may, hence, reduce the required time for the cleaning and coating process as well as reduce the risk of contaminations between the cleaning and coating process. Moreover, this may evade a need for providing a cleaning device capable of housing the entire calotte-shaped substrate holder during the cleaning process. Instead, the cleaning device may be arranged such as to adjoin the coating device housing the calotte-shaped substrate holder. For instance, an opening provided for inserting the calotte-shaped substrate holder into the coating device may be used by the cleaning device for accessing the calotte-shaped substrate holder arranged inside the coating device. Moreover, this may bear the advantage that the cleaning device may be subsequently used in combination with different coating devices. Hence, a cleaning device may be used for several coating devices. This may allow providing only a smaller number of cleaning devices than the number of coating devices.

The coating device and/or the cleaning device may comprise a rubber lip to seal the interface between the opening of the coating device and the cleaning device arranged next to the opening of the cleaning device. This may prevent at least partly in ingress of contaminants from the outside.

A rotational movement of the calotte-shaped substrate holder with respect to the cleaning arm or vice versa may be realized by providing at least one of the following movements: rotating the calotte-shaped substrate holder in the azimuthal direction around the central axis and moving the first cleaning arm in an azimuthal direction around the calotte-shaped substrate holder. A mount for holding the calotte-shaped substrate holder inside a coating device may be motorized with a motor unit to provide the desired rotational movement.

The disclosure further includes a system for cleaning and coating substrates. The system for cleaning and coating substrates comprises a calotte-shaped substrate holder suitable for holding the substrate during a cleaning and coating process. The calotte-shaped substrate holder is rotatable in an azimuthal direction around a central axis of the calotte-shaped substrate holder, wherein the calotte-shaped substrate holder provides one or more rows of mounting slots for mounting the substrates, wherein the rows extend on the calotte-shaped substrate holder in a concentric manner around the central axis of the calotte-shaped substrate holder. The system for cleaning and coating is characterized in that the system further comprises a cleaning device comprising a first arc-shaped cleaning arm having one or more ejection nozzles and one or more suction nozzles arranged at the arc-shaped cleaning arm. The cleaning device is arrangeable with respect to the calotte-shaped substrate holder to extend over the entire altitudinal length of the calotte-shaped substrate holder at a distance of not more than <NUM>,<NUM> from the calotte-shaped substrate-holder and such that the one or more ejection nozzles and the one or more suction nozzles are directed towards the calotte-shaped substrate-holder. All above-disclosed features and properties presented with respect to the cleaning device may apply also for this cleaning and coating system.

Further optional embodiments will be illustrated in the following with reference to the drawings.

In the drawings the same reference signs are used for corresponding or similar features in different drawings.

<FIG> show a cleaning device <NUM> according to an optional embodiment in a perspective view (<FIG>) and in a side view. The cleaning device <NUM> is adapted for cleaning substrates <NUM> mounted on a conventional calotte-shaped substrate holder <NUM> (exemplarily shown in <FIG>), wherein the calotte-shaped substrate holder <NUM> is rotatable in an azimuthal direction <NUM> around a central axis <NUM> of the calotte-shaped substrate holder <NUM>. The cleaning device <NUM> comprises a first cleaning arm <NUM> having one or more ejection nozzles <NUM> and one or more suction nozzles <NUM> arranged at the first cleaning <NUM> arm. The first cleaning arm <NUM> has a circular arc-shape with a radius of curvature in the range from <NUM>,<NUM> to <NUM> and a length in an altitudinal direction <NUM> in the range from <NUM>,<NUM> to <NUM>.

Moreover, the cleaning device <NUM> comprises a second cleaning arm <NUM> having one or more ejection nozzles <NUM> and one or more suction nozzles <NUM> arranged at the second cleaning arm <NUM>, wherein also the second cleaning arm <NUM> has an arc-shape with a radius of curvature in the range from <NUM>,<NUM> to <NUM> and a length in an altitudinal direction <NUM> in the range from <NUM>,<NUM> to <NUM>. The shape of the second cleaning arm <NUM> corresponds to the shape of the first cleaning arm <NUM>. The second cleaning arm <NUM> further comprises a valve <NUM> for connecting hoses or tubing for providing suction at the suction nozzles <NUM>.

The cleaning device <NUM> comprises one or more vertical posts <NUM> extending in the vertical direction <NUM> on which the first and the second cleaning arm <NUM>, <NUM> are mounted. The cleaning arms <NUM>, <NUM> are movable in a vertical direction along the one or more vertical posts <NUM>. Moreover, the cleaning device <NUM> comprises a frame structure <NUM> to support and stabilize the cleaning device <NUM>. According to some embodiments, the frame structure <NUM>,may be adapted to allow arranging the cleaning device <NUM> in such a manner to adjoin a coating device <NUM> (see <FIG>), which may at least partly house the calotte-shaped substrate holder <NUM>.

The frame structure <NUM> may be closed with plate elements extending between the frame elements to form a closed housing of the cleaning device <NUM>. This may allow preventing an ingress of contaminants into the cleaning device <NUM> and/or into a coating device <NUM>, when the cleaning device <NUM> is arranged at the opening of the coating device <NUM>. In addition, this may protect a user from interfering with the moving calotte-shaped substrate holder <NUM>.

According to the presented embodiment, the first cleaning arm <NUM> and the second cleaning arm <NUM> are arranged parallel to each other and spaced apart from each other in a vertical direction <NUM>. This may allow arranging a side wall of a calotte-shaped substrate holder <NUM> to extend between the first and the second cleaning arm <NUM>, <NUM> such that a distance between the first cleaning arm <NUM> and the calotte-shaped substrate holder <NUM> and between the second cleaning arm <NUM> and the calotte-shaped substrate holder <NUM> are optionally constant over the entire overlapping region of the calotte-shaped substrate holder <NUM> and the first and second cleaning arm <NUM>, <NUM>, respectively. According to some embodiments, the vertical spacing between the first cleaning arm <NUM> and the second cleaning arm <NUM>, i.e., along the vertical direction <NUM>, may be in a range from <NUM>,<NUM> to <NUM>,<NUM> and in particular in a range from <NUM>,<NUM> to <NUM>,<NUM>. This may offer a suitable space for arranging the calotte-shaped substrate holder <NUM> in-between and to provide a suitable distance between the cleaning arms <NUM>, <NUM> and the calotte-shaped substrate holder <NUM> to ensure a sufficient stream of cleaning fluid for a reliable cleaning of the substrates <NUM> mounted on the calotte-shaped substrate holder <NUM>.

The first cleaning arm <NUM> and the second cleaning arm <NUM> are directed towards each other such that substrates <NUM> mounted on a calotte-shaped substrate holder <NUM> may be simultaneously cleaned from both sides, i.e. from top and from underneath. For this purpose, the ejection nozzles <NUM> of the first and/or second cleaning arm <NUM>, <NUM> and the ejection nozzles <NUM> of the first and second cleaning arm <NUM>, <NUM> are at least partly directed towards each other.

The second cleaning arm <NUM> further comprises a valve <NUM> for connecting hoses or tubing for providing suction at the suction nozzles <NUM>.

<FIG> reveal an enlarged view on some parts of the cleaning arms <NUM>, <NUM> of the cleaning device presented in <FIG>. In particular, the perspective views presented in <FIG> show the ejection nozzles <NUM> mounted at the respective cleaning arms <NUM>, <NUM>. The presented cleaning arms <NUM>, <NUM> differ from each other in their configuration. The cleaning arm <NUM> shown in <FIG> comprises three ejection nozzles <NUM> and three suction nozzles <NUM> mounted on a sledge <NUM> movable along the cleaning arm <NUM>. A linear actuator may be provided for moving the sledge <NUM> along the cleaning arm <NUM>. For cleaning multiple substrates <NUM> mounted in several concentrical rows <NUM> of mounting slots <NUM> (see <FIG>) on the calotte-shaped substrate holder <NUM>, the sledge <NUM> may be moved along the cleaning arm <NUM> to rearrange the ejection nozzles <NUM> and suction nozzles <NUM> with respect to the rows <NUM> of mounting slots <NUM> in order to sequentially cover all rows <NUM> of mounting slots <NUM>. The movement of the sledge <NUM> may be combined with rotating movement the calotte-shaped substrate holder <NUM> around its central axis <NUM> in order to cover all mounting slots <NUM> in each of the rows <NUM>. The rotation movement of the calotte-shaped substrate holder <NUM> and the movement of the sledge <NUM> along the cleaning arm <NUM>, which corresponds to an altitudinal movement with respect to the calotte-shaped substrate holder <NUM>, may be effectively combined to a spiral movement. Alternatively or additionally, the sledge <NUM> may be moved in a stepwise manner when a full rotation of the calotte-shaped substrate holder <NUM> is completed, to arrange the ejection nozzles <NUM> at the next row of mounting slots <NUM>. The sledge <NUM> may be moved along the cleaning arm <NUM> by means of a gear rack following the shape of the cleaning arm <NUM>. Interfaces <NUM> for connecting a supply of cleaning fluid and/or for suction may be provided at the sides of the sledge <NUM>, which may avoid an undesired interference with the stream of the cleaning fluid and which allows possible hoses connected to the sledge <NUM> to follow the sledge's <NUM> movements in an undisturbed manner. According to other embodiments, the number of ejection nozzles <NUM> and suction nozzles <NUM> arranged on the sledge <NUM> may differ from each other. Therefore, according to some embodiments the at least one of the one or more ejection nozzles <NUM> may be movable in an altitudinal direction <NUM> along the cleaning arm <NUM>.

The cleaning arm <NUM> presented in <FIG> has multiple ejection nozzles <NUM> and suction nozzles <NUM> arranged along the cleaning arm <NUM>. The ejection nozzles <NUM> and suction nozzles <NUM> may be equally spaced from each other and may be distributed over a sufficient length of the cleaning arm <NUM> to extend in an altitudinal direction <NUM> over all rows <NUM> of mounting slots <NUM> provided in a respective calotte-shaped substrate holder <NUM>. This may allow cleaning all substrates <NUM> mounted in the calotte-shaped substrate holder <NUM> within one rotation of the substrate holder <NUM> without a need of moving the ejection nozzles <NUM> and suction nozzles <NUM> in an altitudinal direction <NUM>. Accordingly, a cleaning <NUM> arm according to this embodiment does not require ejection nozzles <NUM> and/or suction nozzles <NUM> mounted on a sledge <NUM> (as compared to <FIG>). Hence, the one or more ejection nozzles <NUM> comprise multiple ejection nozzles <NUM> distributed in the altitudinal direction <NUM> on the cleaning arm <NUM>.

In general, the cleaning device <NUM> may comprise a first cleaning arm <NUM> and a second cleaning arm <NUM>. Each of these cleaning <NUM>, <NUM> arms may be formed according to any one of the presented embodiments. The cleaning arms <NUM> and <NUM> may have an identical configuration or differ from each other.

The one or more ejection nozzles <NUM> and/or the one or more suction nozzles <NUM> may be directed in a radial direction with respect to the first cleaning arm <NUM>. This may allow directing the stream of cleaning fluid directly onto the substrates <NUM> mounted at the substrate holder <NUM>. However, the direction of the ejection nozzles <NUM> and the suction nozzles <NUM> may be tilted with respect to the radial direction in order to achieve a continuous stream of cleaning fluid from the ejection nozzles <NUM> to the suction nozzles <NUM> over the substrates <NUM>.

<FIG> exemplarily depicts a schematic sketch of a conventional coating device <NUM> having a conventional calotte-shaped substrate holder <NUM> arranged therein, as described for instance in <CIT>. The calotte-shaped substrate holder <NUM> is dome-shaped and provides multiple mounting slots <NUM>, which are arranged in several rows <NUM> (two rows according to the presented exemplary calotte-shaped substrate holder <NUM>) extending in a concentrical manner around a central axis <NUM>. Each mounting slot <NUM> may receive a substrate <NUM> and hold the substrate <NUM> such that a lower surface may be exposed to the particle vapor provided by the evaporation source <NUM>. The calotte-shaped substrate holder <NUM> is rotatable around the central axis <NUM>. The rotational movement may be affected by a motor unit <NUM>.

<FIG> shows an exemplary photograph of a conventional coating device <NUM>. The coating device <NUM> may be openable by a respective opening, such as a door <NUM>, which may allow accessing the inside of the coating device <NUM> and, hence, the calotte-shaped substrate holder <NUM>. In particular, when the opening of the coating device <NUM> is opened, for instance by opening the door <NUM>, at least a part of the calotte-shaped substrate holder <NUM> may protrude outside the coating device <NUM> and may be accessed by a cleaning device <NUM> according to an embodiment of the disclosure.

<FIG> shows a schematic sketch of a cleaning device <NUM> according to an embodiment as presented in <FIG> arranged next to an opened coating device <NUM>. The part of the calotte-shaped substrate holder <NUM> protruding from the coating device <NUM> extends in the altitudinal direction <NUM> between the first cleaning arm <NUM> and the second cleaning arm <NUM>, such that the cleaning arms <NUM>, <NUM> extend in the altitudinal direction <NUM> over all rows <NUM> of mounting slots <NUM> provided in the calotte-shaped substrate holder <NUM>. By rotating the calotte-shaped substrate holder <NUM> in the azimuthal direction <NUM>, all substrates <NUM> mounted in the mounting slots <NUM> on the calotte-shaped substrate holder <NUM> may be cleaned. When the cleaning process is completed, the cleaning device <NUM> may be removed from the coating device <NUM> and the coating device <NUM> may be closed to carry out a process for coating the mounted and cleaned substrates <NUM>. Thus, <FIG> depicts a system <NUM> for cleaning and coating substrates <NUM>, wherein the system <NUM> comprises a calotte-shaped substrate holder <NUM> suitable for holding the substrates <NUM> during a cleaning and coating process and a cleaning device <NUM> having the features of claim <NUM>. Moreover, the system <NUM> may include the entire coating device <NUM>.

With reference to <FIG> a method <NUM> for cleaning multiple substrates <NUM> is presented.

The method <NUM> comprises a step <NUM> of mounting the substrates <NUM> at mounting slots <NUM> on a calotte-shaped substrate holder <NUM>, wherein the mounting slots <NUM> are arranged on the calotte-shaped substrate holder <NUM> in one or more rows <NUM> extending in a concentric manner around a central axis <NUM> of the calotte-shaped substrate holder <NUM>.

The method <NUM> further comprises a step <NUM> of arranging an arc-shaped first cleaning arm <NUM> of a cleaning device <NUM> over or underneath the calotte-shaped substrate holder <NUM> such that the arc-shaped first cleaning arm <NUM> of the cleaning device <NUM> extends in an altitudinal direction <NUM> of the calotte-shaped substrate holder <NUM> over at least some of the rows <NUM> of mounting slots <NUM>. The arc-shaped first cleaning arm <NUM> of the cleaning device <NUM> may be arranged over the calotte-shaped substrate holder <NUM>. Moreover, an arc-shaped second cleaning arm <NUM> of the cleaning device <NUM> may be arranged underneath the calotte-shaped substrate holder <NUM> such that the arc-shaped second cleaning arm <NUM> of the cleaning device <NUM> extends in the altitudinal direction <NUM> of the calotte-shaped substrate holder <NUM> over at least some of the rows <NUM> of mounting slots <NUM>.

The method <NUM> further comprises a step <NUM> of cleaning the substrates <NUM> by ejecting a cleaning fluid through one or more ejection nozzles <NUM> provided at the first cleaning arm <NUM> onto the calotte-shaped substrate holder <NUM> and sucking at least a part of the ejected cleaning fluid into one or more suction nozzles <NUM> provided at the first cleaning arm <NUM> and providing a rotational movement of the calotte-shaped substrate holder <NUM> in an azimuthal direction <NUM> around the central axis <NUM> with respect to the first cleaning arm <NUM>. Providing the rotational movement of the calotte-shaped substrate holder <NUM> in the azimuthal direction <NUM> around the central axis <NUM> with respect to the first cleaning arm <NUM> may comprise rotating the calotte-shaped substrate holder <NUM> by at least <NUM>° around the central axis <NUM>. Step <NUM> may further comprise ejecting a cleaning fluid through one or more ejection nozzles <NUM> provided at the second cleaning arm <NUM> onto the substrate holder <NUM> and sucking at least a part of the ejected cleaning fluid into one or more suction nozzles <NUM> provided at the second cleaning arm <NUM>. The provided rotational movement of the calotte-shaped substrate holder <NUM> in an azimuthal direction <NUM> around the central axis <NUM> also applies with respect to the second cleaning arm <NUM>.

The method <NUM> may further comprise a step <NUM> of moving at least one of the one or more ejection nozzles <NUM> along the altitudinal direction <NUM> while providing a rotational movement of the calotte-shaped substrate holder <NUM> in the azimuthal direction <NUM> around the central axis <NUM>.

The method <NUM> may further comprise a step <NUM> of arranging the calotte-shaped substrate holder <NUM> in a coating device <NUM>. This step may be carried out before or after the steps <NUM> and <NUM>. If the method comprises the step <NUM>, the step <NUM> of arranging the arc-shaped first cleaning arm <NUM> of the cleaning device <NUM> over or underneath the calotte-shaped substrate holder <NUM> may comprise arranging the cleaning device <NUM> adjacent to the coating device <NUM>. Moreover, the method may comprise a step <NUM> of removing the cleaning device <NUM> from the coating device <NUM> after cleaning the substrates <NUM> and coating the substrates <NUM> in the coating device <NUM>.

Claim 1:
Cleaning device (<NUM>) adapted for cleaning substrates (<NUM>) for spectacle lenses mounted on a calotte-shaped substrate holder (<NUM>), the calotte-shaped substrate holder (<NUM>) being rotatable in an azimuthal direction (<NUM>) around a central axis (<NUM>) of the calotte-shaped substrate holder (<NUM>),
wherein the cleaning device (<NUM>) comprises a first cleaning arm (<NUM>) having one or more ejection nozzles (<NUM>) and one or more suction nozzles (<NUM>) arranged at the first cleaning arm (<NUM>);
characterized in that
the first cleaning arm (<NUM>) has an arc-shape with a radius of curvature in the range from <NUM>,<NUM> to <NUM> and a length in an altitudinal direction (<NUM>) in the range from <NUM>,<NUM> to <NUM>.