Device for Fixing an Optical Workpiece for its Processing/Treatment and Method of Fixing an Optical Workpiece on such a Device

Abstract

A device (10) for retaining a prismatic spectacle lens (12) at one workpiece surface (14) for processing of the other workpiece surface (16) comprises lower and upper parts (20, 22). The lower part has a base (24) with a holding interface (26) and a wedge section (28). The lower part and upper part are rotatable relative to one another by their mutually facing wedge sections about a rotational axis (DA) inclined with respect to the base axis and retention axis so as to tilt the retaining section and base relative to one another. A wedge orientation arrangement comprises an orientation aid (34) at the upper part and/or an abutment (36) between the upper part and lower part, which defines a relative rotational angle end position of the upper part and lower part corresponding with a minimum or maximum tilt of the retaining section with respect to the base.

Claims

1. A device (10) for retaining an optical workpiece (12), at a first one of two opposite workpiece surfaces (14, 16) for processing or treating the optical workpiece (12) at a second one of the workpiece surfaces (14, 16), comprising a lower part (20) with a base (24), which has a central base axis (BA) and which comprises an interface (26) for three-dimensionally defined securing to a holder, and a lower wedge section (28) adjoining the base (24) along the base axis (BA) and extending transversely to the base axis (BA), and an upper part (22) with a retaining section (30) for the optical workpiece (12), which has a central retention axis (AA), and an upper wedge section (32) adjoining the retaining section (30) along the retention axis (AA) and extending transversely to the retention axis (AA), wherein the lower part (20) and the upper part (22) with the mutually facing lower and upper wedge sections (28, 32) are rotatable relative to one another about a common rotational axis (DA) inclined with respect to the base axis (BA) and the retention axis (AA) so that a relative rotation of the upper part (22) and lower part (20) about the rotational axis (DA) produces relative tilting of the retaining section (30) with respect to the base (24); characterized by a wedge orientation arrangement with, at the upper part (22), an orientation aid (34) by way of which a rotational angle position of the upper part (22) about the base axis (BA) can be determined and/or the upper part (22) is fixable in a rotational angle position about the base axis (BA), and/or with an abutment (36) between the upper part (22) and the lower part (20) which defines at least one rotational angle end position of the upper part (22) with respect to the lower part (20) about the rotational axis (DA) in which the retaining section (30) at the upper part (22) has a minimum or maximum tilt relative to the base (24) of the lower part (20).

2. A device (10) according to claim 1, characterized in that the orientation aid (34) has a projection (50) which projects substantially radially outwardly away from the upper wedge section (32) of the upper part (22) with respect to the rotational axis (DA), or has in the upper part (22) a cut-out (51) extending substantially radially inwardly with respect to the rotational axis (DA).

3. A device (10) according to claim 2, characterized in that the abutment (36) has at the lower part (20) a first abutment section (68) co-operating with a second abutment section (69) of the abutment (36) at the upper part (22).

4. A device (10) according to claim 3, characterized in that the first abutment section (68) and the second abutment section (69) of the abutment (36) as seen in a plan view along the rotational axis (DA) are each configured in the form of a ring segment of 90 and as seen in a circumferential direction about the rotational axis (DA) each have two end-face abutment surfaces (70, 71, 72, 73), wherein one of the abutment surfaces (70, 71) of the first abutment section (68) co-operates with one of the abutment surfaces (72, 73) of the second abutment section (69) so as to fix the maximum tilt of the retaining section (30) at the upper part (22) relative to the base (24) of the lower part (20), whereas another one of the abutment surfaces (70, 71) of the first abutment section (68) co-operates with another one of the abutment surfaces (72, 72) of the second abutment section (69) so as to fix the minimum tilt of the retaining section (30) at the upper part (22) relative to the base (24) of the lower part (20).

5. A device (10) according to claim 4, characterized in that a relative rotational angle position of the upper part (22) and lower part (20) about the rotational axis (DA) is mechanically positively securable in steps.

6. A device (10) according to claim 5, characterized in that formed between the upper part (22) and the lower part (20) is a Hirth toothing (74) with a first toothing section (75) on an upper side of the lower part (20) and a second toothing section (76), which is formed to be complementary with the first toothing section (75), on a lower side of the upper part (22).

7. A device (10) according to claim 6, characterized in that the Hirth toothing (74) has a tooth count of between 28 and 36 teeth and/or the individual teeth of the Hirth toothing (74) have at the radially outer edge of the teeth as referred to the rotational axis (DA) a tooth height of between 1 millimeter and 3 millimeters and/or the individual teeth of the Hirth toothing (74) lie within a circle about the rotational axis (DA) having a radius of between 15 millimeters and 20 millimeters with respect to the rotational axis (DA).

8. A device (10) according to claim 7, characterized in that mounted at the retaining section (30) of the upper part (22) is a flexible retaining ring (60) on which the optical workpiece (12) is placeable by its first workpiece surface (14).

9. A device (10) according to claim 8, characterized in that the flexible retaining ring (60) is made of NBR or EPDM and/or has a hardness according to Shore A of between 15 and 80, preferably between 20 and 50, and/or has a material thickness of between 1.0 millimeter and 8.0 millimeters, preferably between 2.0 millimeters and 5.0 millimeters.

10. A device (10) according to claim 8, characterized by at the upper part (22) an outer vacuum chamber (38) which is bounded at least by an end surface (58) of the retaining section (30) at the upper part (22) and an inner circumferential surface (62) of the flexible retaining ring (60) and can be evacuated for releasable holding of the optical workpiece (12), which is placed on the flexible retaining ring (60), at the first workpiece surface (14).

11. A device (10) according to claim 10, characterized in that the lower part (20) and the upper part (22) bound an inner vacuum chamber (40) which is sealed relative to the environment by a sealing ring (64) and which can be evacuated in order to releasably hold the upper part (22) at the lower part (20) in a predetermined rotational angle setting about the rotational axis (DA).

12. A device (10) according to claim 11, characterized in that the inner vacuum chamber (40) is pneumatically connectible or connected with the outer vacuum chamber (38), the latter preferably by way of a connecting hole (66) in the retaining section (30) of the upper part (22).

13. A device (10) according to claim 12, characterized in that arranged between the lower part (20) and the upper part (22) is a spring element (82) in order to produce between the lower part (20) and the upper part (22) a biasing force which urges the lower part (20) and the upper part (22) apart, and/or formed between the lower part (20) and the upper part (22) is a detent connection (78) which secures the upper part (20) with play to the lower part (22) against loss, preferably comprising at one part a plurality of flexible detent hooks (79) which co-operate with an undercut (80) at the other part, and/or formed between the lower part (20) and the upper part (22) is a centering aid (54) which aligns the upper part (20) and the lower part (22) with respect to the common rotational axis (DA), preferably comprising at one part a substantially hollow-cylindrical sleeve section (55) co-operating with a substantially cylindrical collar (56) at the other part.

14. A device (10) according to claim 1, characterized in that a relative rotational angle position of the upper part (22) and lower part (20) about the rotational axis (DA) is mechanically positively securable in steps.

15. A device (10) according to claim 1, characterized in that mounted at the retaining section (30) of the upper part (22) is a flexible retaining ring (60) on which the optical workpiece (12) is placeable by its first workpiece surface (14).

16. A device (10) according to claim 1, characterized in that the lower part (20) and the upper part (22) bound an inner vacuum chamber (40) which is sealed relative to the environment by a sealing ring (64) and which can be evacuated in order to releasably hold the upper part (22) at the lower part (20) in a predetermined rotational angle setting about the rotational axis (DA).

17. A device (10) according to claim 1, characterized in that arranged between the lower part (20) and the upper part (22) is a spring element (82) in order to produce between the lower part (20) and the upper part (22) a biasing force which urges the lower part (20) and the upper part (22) apart, and/or formed between the lower part (20) and the upper part (22) is a detent connection (78) which secures the upper part (20) with play to the lower part (22) against loss, preferably comprising at one part a plurality of flexible detent hooks (79) which co-operate with an undercut (80) at the other part, and/or formed between the lower part (20) and the upper part (22) is a centering aid (54) which aligns the upper part (20) and the lower part (22) with respect to the common rotational axis (DA), preferably comprising at one part a substantially hollow-cylindrical sleeve section (55) co-operating with a substantially cylindrical collar (56) at the other part.

18. A method for retaining an optical workpiece (12), particularly a spectacle lens, with a first one of two opposite workpiece surfaces (14, 16) at a retaining device (10) for processing or treating the optical workpiece (12) at a second one of the workpiece surfaces (14, 16), comprising the following steps: a) providing the optical workpiece (12) to be processed or treated; b) providing the retaining device (10) for the optical workpiece (12), comprising a lower part (20) with a base (24), which has a central base axis (BA) and which comprises an interface (26) for three-dimensionally defined securing to a holder, and a lower wedge section (28) adjoining the base (24) along the base axis (BA) and extending transversely to the base axis (BA), as well as an upper part (22) with a retaining section (30), which has a central retention axis (AA), for the optical workpiece (12) and an upper wedge section (32) adjoining the retaining section (30) along the retention axis (AA) and extending transversely to the retention axis (AA), wherein the lower part (20) and the upper part (22) by the mutually facing lower and upper wedge sections (28, 32) are rotatable relative to one another about a common rotational axis (DA) which is inclined with respect to the base axis (BA) and the retention axis (AA) so that a relative rotation of the upper part (22) and lower part (20) about the rotational axis (DA) produces a relative tilting of the retaining section (30) with respect to the base (24), wherein the retaining device (10) additionally comprises a flexible retaining ring (60) at the retaining section (30), an outer vacuum chamber (38) bounded at least by an end surface (58) of the retaining section (30) and an inner circumferential surface (62) of the flexible retaining ring (60), and an inner vacuum chamber (40), which is sealed relative to the environment by a sealing ring (64), between the lower part (20) and the upper part (22); c) ensuring that the desired relative tilting of the retaining section (30) at the upper part (22) with respect to the base (24) of the lower part (20) is present; d) placing, with alignment with the retention axis (AA) of the retaining device (10), the optical workpiece (12) by its first workpiece surface (14) on the flexible retaining ring (60) at the retaining section (30) of the upper part (22) of the retaining device (10); and e) evacuating the inner vacuum chamber (40) and the outer vacuum chamber (38) in common in order at the same time to secure the upper part (22) and lower part (20) of the retaining device (10) to one another in the relative rotational setting thereof about the rotational axis (DA) as well as the optical workpiece (12) to the retaining section (30) of the retaining device (10).

19. A method according to claim 18, wherein the step c) of ensuring the desired relative tilting of the retaining section (30) with respect to the base (24) comprises relative rotation of the upper part (22) and lower part (20) of the retaining device (10) about the rotational axis (DA); and/or the step d) of placing the optical workpiece (12), with alignment with respect to the retention axis (AA) of the retaining device (10), comprises centering of the optical workpiece (12) with respect to the retention axis (AA) of the retaining device (10) and/or a rotational angle orientation of the optical workpiece (12) about the retention axis (AA) of the retaining device (10); and/or at least the step e) is carried out in an evacuable container (BH) into which the retaining device (10) and the optical workpiece (12) are inserted; and/or if the step e) is performed in an evacuable container (BH), a step f) of removal of the retaining device (10) and the optical workpiece (12) retained thereat from the evacuable container (BH) follows in which initially the evacuable container (BH) is ventilated, while the optical workpiece (12) is urged substantially along the retention axis (AA) against the flexible retaining ring (60).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The invention is explained in more detail in the following by way of a preferred embodiment with reference to the accompanying partly schematic drawings, in which:

[0047] FIG. 1 shows a side view of a retaining device according to the invention, at which a spectacle lens semi-finished product with a prism is retained and which has a lower part with a lower wedge section and an upper part with an upper wedge section, which lie one on the other and are rotatable relative to one another about a common rotational axis so as to produce a relative tilting of a retaining section, which has a retention axis, of the upper part with respect to a base, which has a base axis, of the lower part, wherein the viewing direction is selected so that the view is frontally of a projection of an orientation aid at the upper part, which indicates the rotational angle position of the upper part about the base axis and is a component of a wedge orientation arrangement;

[0048] FIG. 2 shows a side view of the retaining device with the spectacle lens semi-finished product retained thereat according to FIG. 1, with a viewing direction from the right in FIG. 1;

[0049] FIG. 3 shows a side view of the retaining device with the spectacle lens semi-finished product retained thereat according to FIG. 1, with a viewing direction from the left in FIG. 1;

[0050] FIG. 4 shows an underneath view of the retaining device with the spectacle lens semi-finished product retained thereat according to FIG. 1, with a view of an interface at the base of the lower part, which serves for three-dimensionally defined securing of the retaining device to a holder;

[0051] FIG. 5 shows a perspective exploded illustration of the retaining device and the spectacle lens semi-finished product according to FIG. 1, which as considered from below to above shows the lower part, a sealing ring between the lower part and upper part, the upper part, a flexible retaining ring between the upper part and spectacle lens semi-finished product as well as the spectacle lens semi-finished product, whereinagain considered from below to abovethe base axis, the rotational axis and the retention axis of the retaining device are illustrated and the viewing angle of the perspective view is selected so that the angular adjustment of the mentioned axes with respect to one another or the absent axial alignment thereof is recognizable;

[0052] FIG. 6 shows a perspective view of the lower part of the retaining device according to FIG. 1 from obliquely above and the left, wherein the viewing angle of the perspective view is selected so that, in particular, a first abutment section of an abutment between the upper part and lower part can be seen, which as a further component of the wedge orientation arrangement defines rotational angle end positions of the upper part with respect to the lower part about the rotational axis, in which the retaining section is minimally or maximally tilted relative to the base;

[0053] FIG. 7 shows a perspective view of the upper part of the retaining device according to FIG. 1 from obliquely below and the left, wherein the viewing angle of the perspective view is selected so that, in particular, a lefthand end-face abutment surface of a second abutment section of the abutment between the upper part and lower part can be seen;

[0054] FIG. 8 shows a perspective view of the upper part of the retaining device according to FIG. 1 from obliquely below and the right, wherein the viewing angle of the perspective view is selected so that, in particular, a righthand end-face abutment surface of the second abutment section of the abutment between the upper part and lower part can be seen;

[0055] FIG. 9 shows a perspective view of the upper part of the retaining device according to FIG. 1 from obliquely above and the left, with a view into an outer vacuum chamber which is bounded by an end surface of the retaining section and an inner circumferential surface of the flexible retaining ring and which can be evacuated for detachable holding of a spectacle lens semi-finished product (not shown here) placed on the flexible retaining ring;

[0056] FIG. 10 shows a side view of the retaining device according to FIG. 1 inserted into an evacuable container, which is indicated by dashed lines, of a joining unit, wherein on the side of the retaining device at the left in FIG. 10 there is shown a fixed abutment of the joining unit which co-operates with the projection of the orientation aid at the upper part and wherein the lower part and upper part of the retaining device are in a desired relative rotational setting with respect to one another, here different from a rotational angle end position of the upper part with respect to the lower part, about the axis or rotation;

[0057] FIG. 11 shows a side view of the retaining device according to FIG. 1 in the relative rotational setting of the upper part and lower part in correspondence with FIG. 10, with a viewing direction from the left in FIG. 10 and the fixed abutment of FIG. 10;

[0058] FIG. 12 shows an underneath view of the retaining device according to FIG. 1 in the relative rotational setting of the upper part and lower part in correspondence with FIG. 10, with a viewing direction from below in FIG. 11 and the fixed abutment of FIG. 10;

[0059] FIG. 13 shows a sectional view, which is rotated in clockwise sense in the plane of the drawing, of the retaining device according to FIG. 1 and the fixed abutment of FIG. 10 in correspondence with the section line XIII-XIII in FIG. 10 for illustration of the fact that in the depicted relative rotational setting of the upper part and lower part the first abutment section at the lower part and the second abutment section at the upper part are spaced from one another as seen in circumferential direction about the axis or rotation;

[0060] FIG. 14 shows a sectional view of the retaining device according to FIG. 1 in correspondence with the section line XIV-XIV in FIG. 11;

[0061] FIG. 15 shows a side view of the retaining device according to FIG. 1 and the fixed abutment of FIG. 10, wherein the lower part and upper part are in the relative rotational setting corresponding with FIGS. 10 to 14, but by comparison with FIGS. 10 to 14 the retaining device has in its entirety been rotated about the base axis until the projection, which is provided at the upper part, of the orientation aid has come into contact with the fixed abutment;

[0062] FIG. 16 shows a side view of the retaining device according to FIG. 1 in the relative rotational setting of the upper part and lower part in correspondence with FIGS. 10 to 14, with a viewing direction from the left in FIG. 15 and the fixed abutment of FIG. 10;

[0063] FIG. 17 shows a underneath view of the retaining device according to FIG. 1 in the relative rotational setting of the upper part and lower part in correspondence with FIGS. 10 to 14, with a viewing direction from below in FIG. 16 and the fixed abutment of FIG. 10, wherein a rotational arrow illustrates the rotation of the retaining device in its entirety about the basis axis;

[0064] FIG. 18 shows a sectional view, which is rotated in clockwise sense in the drawing plane, of the retaining device according to FIG. 1 and the fixed abutment of FIG. 10 in correspondence with the section line XVIII-XVIII in FIG. 16, but which in FIG. 16 indicates a sectional plane perpendicular to the rotational axis, thus a sectional plane which is actually slightly tilted with respect to a surface normal of the drawing plane of FIG. 16, again with the rotational arrow of FIG. 17;

[0065] FIG. 19 shows a sectional view, which is rotated in counter-clockwise sense in the drawing plane, of the retaining device according to FIG. 1 in correspondence with the section line XIX-XIX in FIG. 17;

[0066] FIG. 20 shows a side view of the retaining device according to FIG. 1 and the fixed abutment of FIG. 10, wherein the upper part is disposed in the rotational setting held by the fixed abutment and projection and corresponding with FIGS. 15 to 19, but by comparison with FIGS. 15 to 19 the lower part has been rotated about the base axis until the first abutment section of the lower part has come into contact with the second abutment section of the upper part, a rotational angle end position of the lower part with respect to the upper part thus being achieved in which the retaining section here has minimum tilting relative to the base, i.e. is not tilted;

[0067] FIG. 21 shows a side view of the retaining device according to FIG. 1 in the relative rotational setting of the upper part and lower part corresponding with FIG. 20, with a viewing direction from the left in FIG. 20 and the fixed abutment of FIG. 10;

[0068] FIG. 22 shows an underneath view of the retaining device according to FIG. 1 in the relative rotational setting of the upper part and lower part corresponding with FIG. 20, with a viewing direction from below in FIG. 21 and the fixed abutment of FIG. 10, wherein a rotational arrow illustrates the rotation of the lower part with respect to the upper part which has taken place about the base axis;

[0069] FIG. 23 shows a sectional view, which is rotated in clockwise sense in the drawing plane, of the retaining device according to FIG. 1 and the fixed abutment of FIG. 10 in correspondence with the section line XXIII-XXIII in FIG. 20, again with the rotational arrow from FIG. 22 at the lower part;

[0070] FIG. 24 shows a sectional view of the retaining device according to FIG. 1 in correspondence with the section line XXIV-XXIV in FIG. 21, in which it is indicated by dashed auxiliary lines how in the relative rotational setting of the upper part and lower part in correspondence with FIGS. 20 to 23 the wedge angles of the lower wedge section and the upper wedge section are mutually cancelling so that the retaining section is not tilted with respect to the base;

[0071] FIG. 25 shows a side view of the retaining device according to FIG. 1 and the fixed abutment of FIG. 10, wherein by comparison with FIGS. 20 to 24 the lower part has been rotated back about the base axis with respect to the upper part held by way of the projection at the fixed abutment until a predetermined tilting of the retaining section with respect to the base of here, for example, 7 is achieved;

[0072] FIG. 26 shows a side view of the retaining device according to FIG. 1 in the relative rotational setting of the upper part and lower part in correspondence with FIG. 25, with a viewing direction from the left in FIG. 25, the fixed abutment of FIG. 10 and a locking element, which is indicated by a rectangle and retractable perpendicularly to the drawing plane and which in correspondence with the fixed abutment is capable of holding the upper part against rotation at the projection of the orientation aid;

[0073] FIG. 27 shows an underneath view of the retaining device according to FIG. 1 in the relative rotational setting of the upper part and lower part in correspondence with FIG. 25, with a viewing direction from below in FIG. 26, the fixed abutment of FIG. 10 and the locking element of FIG. 26, wherein a rotational arrow illustrates the (return) rotation, which has taken place about the base axis, of the lower part with respect to the upper part, whereas a double arrow illustrates the movement possibility of the locking element;

[0074] FIG. 28 shows a sectional view, which is rotated in clockwise sense in the drawing plane, of the retaining device according to FIG. 1, the fixed abutment of FIG. 10 and the locking element of FIG. 26 in correspondence with the section line XXVIII-XXVIII in FIG. 26, again with the rotational arrow and the double arrow of FIG. 27;

[0075] FIG. 29 shows a sectional view of the retaining device according to FIG. 1 in correspondence with the section line XXIX-XXIX in FIG. 25;

[0076] FIG. 30 shows a sectional view of the retaining device with the spectacle lens semi-finished product, which is retained thereat, according to FIG. 1 in correspondence with the section line XXX-XXX in FIG. 2, wherein the relative rotational setting of the upper part and lower part corresponds with that from FIGS. 25 to 29 and wherein an optional spring element, which generates a biasing force urging the lower part and upper part apart, is indicated by a dashed line at a central position between the lower part and upper part;

[0077] FIG. 31 shows a sectional view, which is rotated in clockwise sense in the drawing plane, of the retaining device with the spectacle lens semi-finished product according to FIG. 1 retained thereat in correspondence with the section line XXXI-XXXI in FIG. 1, i.e. in the relative rotational setting of the upper part and lower part as in FIG. 30;

[0078] FIG. 32 shows a side view of the retaining device according to FIG. 1 and the fixed abutment of FIG. 10, wherein the upper part is in the rotational setting with respect to the fixed abutment corresponding with FIGS. 15 to 29, but by comparison with FIGS. 20 to 24 the lower part is rotated in the opposite direction about the base axis until the first abutment section of the lower part has come into contact by its other end-face abutment surface with the other end-face abutment surface of the second abutment section of the upper part, a rotational angle end position of the lower part with respect to the upper part thus being achieved in which the retaining section has a maximum tilt relative to the base;

[0079] FIG. 33 shows a side view of the retaining device according to FIG. 1 in the relative rotational setting of the upper part and lower part in correspondence with FIG. 32, with a viewing direction from the left in FIG. 32, the fixed abutment of FIG. 10 and again the locking element of FIG. 26, which in co-operation with the fixed abutment holds the upper part against rotation at the projection of the orientation aid;

[0080] FIG. 34 shows an underneath view of the retaining device according to FIG. 1 in the relative rotational setting of the upper part and lower part in correspondence with FIG. 32, with a viewing direction from below in FIG. 33, the fixed abutment of FIG. 10 and the locking element of FIG. 26, wherein again a rotational arrow illustrates the (return) rotation, which has taken place about the base axis, of the lower part with respect to the upper part, whereas a double arrow illustrates the movement possibility of the locking element;

[0081] FIG. 35 shows a sectional view, which is rotated in clockwise sense in the drawing plane, of the retaining device according to FIG. 1, the fixed abutment of FIG. 10 and the locking element of FIG. 26 in correspondence with the section line XXXV-XXXV in FIG. 32, again with the rotational arrow and the double arrow of FIG. 34, wherein illustrated in a dot-dashed-line box as an alternative to the projection of the orientation aid is a cut-out in the upper part into which a slide, as an alternative to the fixed abutment and locking element, is movable so as to secure the upper part in the illustrated rotational setting; and

[0082] FIG. 36 shows a sectional view of the retaining device according to FIG. 1 and the locking element of FIG. 26 in correspondence with the section line XXXVI-XXXVI in FIG. 33, in which it is indicated by dashed auxiliary lines how in the relative rotational setting of upper part and lower part in correspondence with FIG. 32 the wedge angle of the lower wedge section and the upper wedge section add together so that the retaining section has a maximum tilt with respect to the base, wherein analogously to FIG. 35 the alternative rotational securing of the upper part with cut-out and slide is shown in a dot-dashed-line box.

[0083] In general it is be noted at this point with respect to the drawings that in FIGS. 6 to 8, 13, 18, 23, 28, 31 and 35 there is shown at the lower part and upper part of the retaining device a central marking B which in the concrete embodiment characterizes the type of retaining device according to sizein order to cover the desired spectrum of diameter and curvature of the spectacle lens it can be necessary to use several variants of the retaining devicewhich, however, is without significance for the functioning of the retaining device. Nevertheless, this marking is illustrated here so as to achieve a more rapid orientation with respect to the respective rotational position of the lower part and upper part.

DETAILED DESCRIPTION OF THE EMBODIMENT

[0084] A device for retaining an optical workpiecealso called retaining device for short in the present applicationis denoted generally by the reference numeral 10 in FIGS. 1 to 5 and 10 to 36. A spectacle lens semi-finished producttermed spectacle lens 12 for short in the followingis illustrated in FIGS. 1 to 5, 30 and 31 as an example of an optical workpiece retained or to be retained at the retaining device 10. The spectacle lens 12 has twoin each case at the end of processingoptically effective workpiece surfaces 14, 16 and a workpiece edge 18 therebetween. The retaining device 10 generally serves the purpose of retaining the spectacle lens 12 at a first one (workpiece surface 14) of the two opposite workpiece surfaces 14, 16 for processing or treating the spectacle lens 12 at a second one (workpiece surface 16) of the workpiece surfaces 14, 16. The processing can be, for example, polishing, which is known per se, of the workpiece surface 16 of the spectacle lens 12 and the treatment can be, for example, marking, which is known per se, of the workpiece surface 16 of the spectacle lens 12 as already described in the introduction.

[0085] A special feature of the spectacle lens 12 illustrated herein is that, as FIGS. 1 to 3, 5 and 30 show, the spectacle lens 12 has a prism, i.e. the two workpiece surface 14, 16 are set at a defined angle with respect to one another, thus are tilted relative to one another, so that the spectacle lens 12 has to a certain extent a wedge shape. In order to ensure with such a workpiece shape that the spectacle lens 12 rotated about an rotational axis during or for the processing or treatment does not excessively wobble with respect to a plane transverse to the rotational axis by its workpiece surface 16 to be processed or treated, the retaining device 10 is constructed adaptively, i.e. it can be adapted to the prism of the spectacle lens 12 or provide compensation for this, as explained in more detail in the following.

[0086] As can be readily recognized in FIGS. 5 to 9, the retaining device 10 generally comprises a lower part 20 and an upper part 22. The lower part 20, which is shown separately in FIGS. 5 and 6, of the retaining device 10 has at the outset a base 24 with a central base axis BA. The base 24 has an interface 26, which is known per se, for three-dimensionally defined securing to a holder (not shown) of a machine or device for processing or treating the spectacle lens 12. In addition, the lower part 20 comprises a lower wedge section 28 which adjoins the base 24 along the base axis BA and which extends transversely to the base axis BA.

[0087] The upper part 22, which is shown separately in FIGS. 5 and 7 to 9, of the retaining device 10 on the other hand has a retaining section 30, which has a central retention axis AA, for the spectacle lens 12. Moreover, the upper part 22 has an upper wedge section 32 which adjoins the retaining section 30 along the retention axis AA and which extends transversely to the retention axis AA.

[0088] The lower wedge section 28 of the lower part 20 and the upper wedge section 32 of the upper part 22 have a common rotational axis DA, which is inclined not only with respect to the base axis BA, but also to the retention axis AA, as indicated in FIG. 5 by angle arrows. As described in more detail further below, the lower part 20 and the upper part 22 in the mounted state of the retaining device 10 are rotated by the mutually facing lower and upper wedge sections 28, 32 relative to one another about the common rotational axis DA, in which case the relative rotation of the lower part 20 and upper part 22 about the rotational axis DA produces a relative tilting of the retaining section 30 of the upper part 22 with respect to the base 24 of the lower part 20.

[0089] As also explained in detail in the following, different measures i), ii) and iii) which improve, especially simplify and accelerate, the setting and holding of a defined prismatic tilting of the spectacle lens 12 at the retaining device 10 in an at least partly automated production environment are undertaken at the retaining device 10. These measures i) to iii) are, in fact, realized together in the illustrated embodiment for the retaining device 10, but this is not obligatory, i.e. they can also each be used individually.

[0090] Thus, the retaining device 10 at the outset is provided with a wedge orientation arrangement which in the illustrated embodiment comprises (inter alia) not only i) an orientation aid 34 at the upper part 22, as can be readily seen, for example, in FIGS. 7 to 9, but also ii) an abutment 36 between the upper part 22 and the lower part 20 (see with respect thereto, in particular, the sectional views according to FIGS. 13, 18, 23, 28, 31 and 35). Whereas by way of i) the orientation aid 34 at the upper part 22 it is possible for a rotational angle position of the upper part 22 about the base axis BA to be fixed and/or the upper part 22 to be able to be fixed in a rotational angle position about a base axis BA, ii) the abutment 36 provided between the upper part 22 and the lower part 20 defines about the rotational axis DA at least one rotational angle end position (in the illustrated embodiment two rotational angle end positions) of the upper part 22 with respect to the lower part 20, in which the retaining section 30 at the upper part 22 is tilted relative to the base 24 of the lower part 20 minimally (cf. FIGS. 20 to 24) or maximally (see FIGS. 32 to 36).

[0091] Moreover, iii) an outer vacuum chamber 38 is provided at the upper part 22 of the retaining device 10 (cf., for example, FIG. 9), which can be evacuated for releasable holding of the spectacle lens 12 at the first workpiece surface 14, whereas formed between the lower part 20 and the upper part 22 of the retaining device 10 is, in addition, an inner vacuum chamber 40 (see, for example, FIGS. 14, 19, 24, 29, 30 and 36) which can be evacuated so as to releasably hold the upper part 22 in a predetermined rotational angle setting about the rotational axis DA at the lower part 20. In that regard, a further special feature includes the fact that common evacuation of the inner vacuum chamber 40 and the outer vacuum chamber 38 is made possible so as to simultaneously secure the upper part 22 and lower part 20 of the retaining device 10 to one another in the relative rotational setting thereof about the rotational axis DA as well as the spectacle lens 12 to the retaining section 30 of the retaining device 10, as is explained in detail further below.

[0092] According to, in particular, FIGS. 1 to 5 the interface 26 at the base 24 of the lower part 20 has, in a manner which is known per se, different surfaces by way of which the retaining device 10 can be held with clear definition in three dimensionsas well as mechanically positively and with a capability of rotational entrainmentat a holder, for example, a collet chuck of a workpiece spindle (not shown). In that regard, the surfaces are in detailfor simplification of the illustration these are indicated by reference numbers only in FIGS. 1 to 5a height reference surface 42 extending transversely to the base axis BA, a centering surface 44 at the outer circumference of the base 24, a rotational entrainment cut-out 46, which also extends transversely to the base axis BA and which is continuous and V-shaped in cross-section, and a depression 48, which is angularly offset with respect thereto in circumferential direction about the base axis BA, for rotational angle orientation of the lower part 20.

[0093] It is at the outset obvious particularly from FIGS. 1 to 5 and 7 to 9 at the outside of the upper part 22 of the retaining device 10 that the orientation aid 34 has a projection 50 which extends substantially radially outwardly with respect to the rotational axis DA away from the upper wedge section 32 of the upper part 22. In an embodiment which is an alternative thereto the orientation aid 34 at the upper part 22 can, however, also have a cut-out 51 which extends substantially radially inwardly with respect to the rotational axis DA as is shown in the small boxes of FIGS. 35 and 36 bounded by dot-dashed lines.

[0094] The wedge orientation arrangement further comprises externally visibleindeed even when a retaining device 10 is inserted by the base 24 into a holdermarking slots 52, 53 in the lower wedge section 28 of the lower part 20 and the upper wedge section 32 of the upper part 22, which indicate in which relative rotational setting the lower part 20 and upper part 22 are disposed. If these marking slots 52, 53 are congruent, as shown in FIGS. 22 to 24, then the retaining section 30 of the upper part 22 has a minimum tilt with respect to the base 24 of the lower part 20, i.e. in the illustrated embodiment not tilted. If, on the other hand the marking slots 52, 53 lie on diametrically opposite sides of the retaining device 10 with respect to the rotational axis DA, as illustrated in FIGS. 34 to 36, then the retaining section 30 has a maximum tilt with respect to the base 24.

[0095] Moreover, in the transition region from the lower part 20 and upper part 22 it can be seen at the outside that formed between the lower part 20 and the upper 22 is a centering aid 54 which aligns the upper part 22 and the lower part 20 with respect to the common rotational axis DA. In the illustrated embodiment the centering aid 54 comprises a substantially hollow-cylindrical sleeve section 55 at the upper part 22, which co-operates with a substantially cylindrical collar 56 at the lower part 20, as can be best seen in the sectional views according to FIGS. 14, 19, 24, 29, 30 and 36.

[0096] The retaining section 30 of the upper part 22 has an end surface 58, which faces away from the lower part 20 and which is formed to be concave. A flexible retaining ring 60 on which the spectacle lens 12 can be placed by its first workpiece surface 14 is mounted on the retaining section 30 of the upper part 22 in the region of the end surface 58 or surrounding this. As already mentioned in the introduction, the flexible retaining ring 60 can be made of, for example, NBR (nitrile butadiene rubber) or EPDM (ethylene-propylene-diene; M group) and preferably has a hardness according to Shore A of between 15 and 80, more preferably between 20 and 50. However, as an alternative thereto a foam ring of, for example PUR (polyurethane elastomer) is conceivable, which is provided with a cover of natural rubber and has a similar hardness range. A suitable, in a given case uniform, material thickness for such a flexible retaining ring 60 is preferably between 1.0 millimeter and 8.0 millimeters, more preferably between 2.0 millimeters and 5.0 millimeters. The concave form of the end surface 58 makes it possible, by its comparatively strong curvature as well as the flexible, adaptable retaining ring 60, to hold spectacle lenses 12 with widely different front curvatures at its respective workpiece surface 14.

[0097] As far as the operating principle of the holding is concerned, provided at the upper part 22 of the retaining device 10 in accordance with, in particular, FIGS. 9, 14, 19, 24, 29, 30 and 36 is the outer vacuum chamber 38 which (inter alia) is bounded by the end surface 58 of the retaining section 30 at the upper part 22 and an inner circumferential surface 62 of the flexible retaining ring 60. In addition, the outer vacuum chamber 38 can be tightly closed by the workpiece surface 14 of the spectacle lens 12 on the side of the flexible retaining ring 60 remote from the base 24 and can be evacuated for releasable holding of the spectacle lens 12 placed on the flexible retaining ring 60, as is described in the following.

[0098] The interior of the retaining device 10 can be best seen in the perspective views according to FIGS. 6 to 8 and the sectional views according to FIGS. 14, 19, 24, 29, 30 and 36. Accordingly, firstly the inner vacuum chamber 40, which is bounded by the lower part 20 and the upper part 22 and which can be ventilated so as to releasably hold the upper part 22 at the lower part 20 in a predetermined rotational angle setting about the rotational axis DA, is sealed relative to the environment by a sealing ring 64. The sealing ring 64 can be, for example, an O-ring as illustrated in the mentioned figures. In a variant, the inner vacuum chamber 40 can in that case be pneumatically connected with the outer vacuum chamber 38 by way of a connecting hole 66 in the retaining section 30 of the upper part 22, as indicated by dashed lines in FIGS. 7 to 9, 29 and 30, so that the inner vacuum chamber 40 can also be ventilated by way of the outer vacuum chamber 38 or conversely.

[0099] Moreover, the abutment 36, which was already briefly described further above, of the wedge orientation arrangement is formed in the interior of the retaining device 10. According to, in particular, FIGS. 6 to 8 the abutment 36 has at the lower part 20 a first abutment section 68 which co-operates with a second abutment section 69 of the abutment 36 at the upper part 22. The first abutment section 68 and the second abutment section 69 of the abutment 36 are each constructed in the form of a ring segment of 90 as seen in plan view along the rotational axis DA and each have two end-face abutment surfaces 70, 71, 72, 73 as seen in a circumferential direction about the rotational axis DA. One (abutment surface 70) of the abutment surfaces 70, 71 of the first abutment section 68 in that case co-operates with one (abutment surface 72) of the abutment surfaces 72, 73 of the second abutment section 69 so as to fix the maximum tilt of the retaining section 30 at the upper part 22 relative to the base 24 of the lower part 20 (see FIG. 35). Another one (abutment surface 71) of the abutment surfaces 70, 71 of the first abutment section 68 on the other hand co-operates with another one (abutment surface 73) of the abutment surfaces 72, 73 of the second abutment section 69 so as to fix the minimum tilt of the retaining section 30 at the upper part 22 relative to the base 24 of the lower part 20 (cf. FIG. 23).

[0100] A further special feature of the retaining device 10 is that a relative rotational angle position of the lower part 20 and upper part 22 about the rotational axis DA can be mechanically positively secured in steps. A Hirth toothing 74 is in turn formed for this purpose in the interior of the retaining device 10 between the lower part 20 and the upper part 22. The Hirth toothing 74 comprises a first toothing section 75 on an upper side of the lower part 20 and a second toothing section 76, which is formed to be complementary to the first toothing section 75, on a lower side of the upper part 22. In the mounted state of the retaining device 10 the two toothing sections 75, 76 interengage mechanically positively and with self-centering in a manner known per se for a Hirth toothing 74 when the inner vacuum chamber 40 is evacuated and in that case the sealing ring 64 between the lower part 20 and upper part 22 is compressed under axial approach of the upper part 22 and lower part 20. As a result, an undesired relative rotation of the lower part 20 and upper part 22 is then prevented by interlock.

[0101] For a concrete case of use, investigations by the inventors have shown that the Hirth toothing 74 should have a tooth count of between 28 and 36 teeth. The individual teeth of the Hirth toothing 74 at the radially outer edge of the teeth as referred to the rotational axis DA should, in addition, have a tooth height of between 1 millimeter and 3 millimeters. Moreover, the individual teeth of the Hirth toothing 74 should lie within a circle about the rotational axis DA which has a radius of between 15 millimeters and 20 millimeters with respect to the rotational axis DA. Resulting therefrom is a comparatively steep radial course of the individual teeth of the Hirth toothing 74 referred to a notional plane transverse to the rotational axis DA. In other words, as considered in a projection onto a plane containing the center axis(=rotational axis DA) of the Hirth toothing 74 the tooth root and tooth crown of a tooth of the Hirth toothing 74 include an angle of inclination which is relatively large for a Hirth toothing.

[0102] Moreover, in order to secure the upper part 22 of the retaining device 10 to the lower part 20, with play, against loss or unintended separation from the lower part 20 there is formedagain in the interior of the retaining device 10a detent connection 78 between the lower part 20 and the upper part 22. As can be best seen in the perspective view according to FIGS. 6 to 8, the detent connection 78 comprises a plurality of flexible detent hooks 79 at one part, here the lower part 20, which co-operate in axially detenting manner with an associated annular undercut 80 at the other part, here the upper part 22.

[0103] In terms of structure it is additionally to be noted with respect to the retaining device 10 that, as indicated in FIG. 30 at the reference numeral 82 with a dashed line, a spring element can also be arranged between the lower part 20 and the upper part 22 in order to produce between the lower part 20 and the upper part 22 a biasing force which urges the lower part 20 and the upper part 22 apart so as to assist release of these parts from one another when the inner vacuum chamber 40 shall be or is ventilated.

[0104] Finally, as far as the wedge configuration of the wedge sections 28, 32 at the lower part 20 and upper part 22 are concerned FIGS. 24 and 36 illustrate the range of tilting, which is possible with this embodiment, of the retaining section 30 at the upper part 22 with respect to the base 24 of the lower part 20. In the illustrated embodiment the wedge sections 28, 32 each have a wedge angle KW of 5. In one rotational angle end position, which is defined by the abutment surfaces 71, 73 of the abutment 36, of the lower part 20 with respect to the upper part 22 (cf. FIG. 23) these wedge angles KW are mutually cancelling so that the retaining section 30 is not tilted with respect to the base 24 (see FIG. 24). A spectacle lens 12 without a prism, for example, can be retained at a retaining device 10 set in such a way.

[0105] FIG. 36, on the other hand, illustrates the case in which the lower part 20 and upper part 22 of the retaining device 10 are rotated relative to one another into abutment in the opposite rotational direction. In this other rotational angle end position, which is defined by the abutment surfaces 70, 72 of the abutment 36, of the lower part 20 with respect to the upper part 22 (cf. FIG. 35) the stated wedge angles KW add together so that the retaining section 30 is maximally tilted with respect to the base 24 and, in particular, by 10 (see FIG. 36). A spectacle lens 12 with a prism of, for example 10 can then be retained at a retaining device 10 set in such a way.

[0106] Depending on the division of the Hirth toothing 74 different tiltings of the retaining section 30 at the upper part 22 with respect to the base 24 of the lower part 20 are settable therebetween in steps, wherein the deformation capability of the flexible retaining ring 60 allows a spectacle lens 12 with a prism between 0 and, for example 10 to be respectively retained at the suitably set retaining device 10 in such a way that its workpiece surface 16, which is to be processed or treated, ultimately has substantially no tilt with respect to the base 24 of the retaining device 10.

[0107] In conclusion, the method for retaining the spectacle lens 12 by its first workpiece surface 14 at the retaining device 10 for processing or treatment of the spectacle lens 12 at its second workpiece surface 16 shall be briefly described with reference to the different method stages according to 1) FIGS. 10 to 14 (initial desired tilt of, for example, 3), 2) FIGS. 15 to 19 (tilt of 3 prior to resetting), 3) FIGS. 20 to 24 (resetting the tilt to 0), 4) FIGS. 25 to 29 (fresh setting of the tilt to, for example, 7), 5) FIGS. 1 to 4, 30 and 31 (retaining the spectacle lens 12 at a tilt of, for example, 7) and 6) FIGS. 32 to 36 (illustration of the maximum tilt of 10).

[0108] In general the method comprises the following steps: a) providing the spectacle lens 12 which is to be processed or treated and which has or is to have a predetermined prism; b) providing the afore-described adaptively constructed retaining device 10 for the spectacle lens 12; c) ensuring that the desired relative tilt of the retaining section 30 at the upper part 22 of the retaining device 10 with respect to the base 24 of the lower part 20 is present; d) placingaligned with respect to the retention axis AA of the retaining device 10of the spectacle lens 12 by its first workpiece surface 14 on the flexible retaining ring 60 at the retaining section 30 of the upper part 22 of the retaining device 10; and e) evacuating in common the inner vacuum chamber 40 and the outer vacuum chamber 38 so as to simultaneously secure the upper part 22 and the lower part 20 of the retaining device 10 to one another in the relative rotational setting thereof about the rotational axis DA as well as the spectacle lens 12 to the retaining section 30 of the retaining device 10.

[0109] The steps a) and b) of providing the workpiece (spectacle lens 12) and workpiece retainer (retaining device 10) obviously assume in an (partly) automated process sequence the presence of appropriate handling devices for positioning the workpiece and workpiece retainer in three dimensions, but these are not explained in more detail at this point since they are sufficiently known to the person ordinarily skilled in the art. In particular, provision of the retaining device 10 in an (partly) automated process sequence comprises loading the retaining device 10 into a joining unit FE, which is illustrated in FIG. 10 by dashed lines by way of example and merely schematically.

[0110] The joining unit FE in this example comprises a container BH which can be tightly closed by a cover DE and evacuated by way of a vacuum connection VA. A holder HA for retaining the base 24 of the retaining device 10 at the interface 26 thereof is arranged in the container BH. The holder HA is rotatable in defined manner, i.e. controlled in rotational angle, as indicated by the rotary arrow in FIG. 10. In addition, this holder HA in the form of a conventional collet chuck has a geometry which is complementary with the interface 26 at the base 24 of the lower part 20 and which allows retention of the interface 26 with interlocking and with centering with respect to the base axis BA as well as orientation in rotational angle and a capability of rotational entrainment. Moreover, present in the container BH at a fixed position is a fixed abutment FA of the joining unit FE, which co-operates with the projection 50 of the orientation aid 34 at the upper part 22, more precisely with which the projection 50 can be brought into contact. Finally, also provided in the container BH is a locking element VG (not shown in FIG. 10, but indicated in FIGS. 26 to 28 and 33 to 36) which is linearly displaceable by way of, for example, a piston-cylinder arrangement and which in co-operation with the fixed abutment FA can hold the upper part 22 against rotation at the projection 50 of the orientation aid 34.

[0111] In principle, at the time of providing the retaining device 10 in accordance with step b) the retaining section 30 thereof can already have a known tilt with respect to the base 24. In such a case it merely has to be verified in step c) of ensuring the tilting that the desired or required tilt of the retaining section 30 at the retaining device 10 is present. This can be carried out in the joining unit FE, for example, by measuring with the assistance of the marking slots 52, 53 at the lower part 20 and upper part 22, their relative rotational angle position being representative of a specific tilt of the retaining section 30 with respect to the base 24 of the retaining device 10.

[0112] If, however, the lower part 20 and the upper part 22 of the retaining device 10 are in an arbitrary relative rotational setting with respect to one another about the rotational axis DA the tilt of the retaining section 30 with respect to the base 24 is correspondingly arbitrary. In this case the step c) of ensuring the desired relative tilt of the retaining section 30 with respect to the base 24 comprises a relative rotation of the upper part 22 and lower part 20 of the retaining device 10 about the rotational axis DA.

[0113] FIGS. 10 to 13 show the retaining device 10 in this undefined relative rotational setting of the lower part 20 and upper part 22 directly after insertion into the holder HA of the joining unit FE. Starting from this setting, the lower part 20 of the retaining device 10 together with the upper part 22, which rests thereon, of the retaining device 10 is initially rotated by a rotation of the holder HA of the joining unit FE to such an extent about the base axis BA that the projection 50, which is provided at the upper part 22, of the orientation aid 34 comes into contact with the fixed abutment FA of the joining unit FE, as FIGS. 15 to 19 illustrate.

[0114] Since the upper part 22 of the retaining device 10 is now secured by the fixed abutment FA against further rotation, the lower part 20 of the retaining device 10 is, in the case of further rotation of the holder HA about the base axis BA relative to the upper part 22 of the retaining device 10, rotated untilas illustrated in FIG. 23 from FIGS. 20 to 24the first abutment section 68 of the lower part 20 comes into contact with the second abutment section 69 of the upper part 22 (contact of the end-face abutment surfaces 71 and 73), thus achieving a rotational angle end position of the lower part 20 with respect to the upper part 22 in which here the retaining section 30 is minimally tilted, i.e. not tilted, relative to the base 24.

[0115] When this rotational setting is achieved, fixing of the desired relative rotational setting and thus the desired tilt of the retaining section 30 with respect to the base 24 can be carried out with knowledge of the relative rotational setting between the upper part 22 and lower part 20 of the retaining device 10. For that purpose, in correspondence with the illustrations in FIGS. 25 to 29 initially the locking element VG is actuated, which on the side remote from the fixed abutment FA comes into contact against the projection 50, which is provided at the upper part 22, of the orientation aid 34 and in that case secures the upper part 22 of the retaining device 10 against rotation in the opposite rotational direction. The lower part 20 is then rotated (back) through the appropriate rotational angle in correspondence with the rotational arrow in FIG. 27 with respect to the upper part 22 of the retaining device 10 for fixing the desired tilt of the retaining section 30.

[0116] Placingaligned with respect to the retention axis AA of the retaining device 10of the spectacle lens 12 by its first workpiece surface 14 on the flexible retaining ring 60 at the retaining section 30 of the upper part 22 of the retaining device 10 is subsequently carried out in accordance with step d), wherein this step includes centering of the spectacle lens 12 with respect to the retention axis AA of the retaining device 10 and/or rotational angle orientation of the spectacle lens 12 about the retention axis AA of the retaining device 10. In an (partly) automated process sequence the handling system associated with the spectacle lens 12 must thus have appropriate degrees of freedom of movement.

[0117] The inner vacuum chamber 40 and the outer vacuum chamber 38 of the retaining device 10 are then evacuated together in step e) so as to simultaneously secure the upper part 22 and lower part 20 of the retaining device 10 to one another in the relative rotational setting thereof about the rotational axis DA as well as the spectacle lens 12 to the retaining section 30 of the retaining device 10. In the illustrated embodiment this takes place by application of a vacuum to the evacuable container BHwhich in that case is tightly closed by the cover DE according to FIG. 10, in which the retaining device 10 and the spectacle lens 12 are now disposed in the desired relative position with respect to one anotherand, in particular, by way of the vacuum connection VA of the container BH.

[0118] In the embodiment described herein this step is followed by a step f) of removal of the retaining device 10 and spectacle lens 12 retained thereat from the evacuable container BH, in which initially the evacuable container BH is ventilated and, in particular, by way of the vacuum connection VA and/or by opening the cover DE, while the spectacle lens 12 is urged substantially along the retention axis AA against the flexible retaining ring 60 (not shown in the figures). The urging during ventilation of the evacuable container BH prevents the inner vacuum chamber 40 or the outer vacuum chamber 38 of the retaining device 10 from being erroneously ventilated therewith. The reasons for that would be an undesired contact of one of the sealing front surfaces or a compression spring (spring element 82) which might be arranged between the lower part 20 and the upper part 22, as illustrated in FIG. 30, which during separation of the spectacle lens 12 and retaining device 10 optionally facilitates desired ventilation of the inner vacuum chamber 40.

[0119] The spectacle lens 12 heldin a given case prismaticallyat the retaining device 10 can, if desired, now be processed or treated at the free workpiece surface 16. If after the processing or treatment the spectacle lens 12 is to be separated again from the retaining device 10, it is possible to re-insert the retaining device 10 together with the spectacle lens 12 into the evacuable container BH and to evacuate this more strongly than in the case of the preceding joining. This has the effect that the higher pressure then prevailing in the vacuum chambers 38, 40 endeavors to drive the individual parts apart.

[0120] The above-described retaining device 10 and the method illustrated here make it possible, for example in the production process of spectacle lenses 12, to retainin a given case also prismaticallythe respective spectacle lens 12, for example after generation of the optically active shape, in simple manner specifically for a downstream polishing process so that the spectacle lens 12 does not in the process sequence have to be conventionally blocked for the downstream polishing process. The same applies to further treatment steps such as, for example, laser engraving. To that extent the retaining device 10 and the described retaining method are particularly tailored to use in a blockless production process for spectacle lenses, such as is the subject of documents DE 10 2021 004 831 A1, DE 10 2021 005 202 A1 and DE 10 2021 005 399 A1, to which express reference may be made at this point with respect to further process details.

[0121] A device for retaining, in particular, a prismatic spectacle lens at one workpiece surface for processing or treatment of the other workpiece surface comprises lower and upper parts. The lower part has a base with a holding interface and a wedge section transverse to the basis axis. The upper part comprises a spectacle lens retaining section and a wedge section transverse to the retention axis. The lower part and upper part are rotatable relative to one another by their mutually facing wedge sections about an rotational axis inclined with respect to the base axis and retention axis so as to tilt the retaining section and base relative to one another. A wedge orientation arrangement comprises, for determining or fixing an upper part rotational angle position about the base axis, an orientation aid at the upper part and/or an abutment between the upper part and lower part, which defines a relative rotational angle end position of the upper part and lower part corresponding with a minimal or maximal tilt of the retaining section with respect to the base. Outer and inner vacuum chambers of the device can be evacuated in common so as to couple the lower part, upper part and spectacle lens.

[0122] Other variations and modifications are possible without departing from the scope and spirit of the present invention as defined by the appended claims.