METHOD AND EXPOSURE DEVICE FOR EXPOSING AT LEAST ONE STORED REPRESENTATION ON A LIGHT-SENSITIVE RECORDING MEDIUM

Abstract

The invention relates to a method for exposing at least one stored image (21) on a light-sensitive recording medium (14), with an exposure device (11), which picks up at least one recording medium (14) on a support (12), with at least one exposure head (16, 17), which is moved above the support (12) along a guiding axis (18) in the X direction and the guiding axis (18) and/or the support (12) are moved in the Y direction, with a control system, by which a traversing movement of the at least one exposure head (16, 17) is operated for exposing the at least one image (21) of the recording medium (14) and/or the recording medium (14), wherein the position of the recording medium (14) and/or the position of the at least one image (21) on the recording medium (14) are detected with at least one linear image acquisition device (25), which extends at least partially in the X direction.

Claims

1. Method for exposing at least one stored image on a light-sensitive recording medium, having an exposure device, which picks up at least one recording medium on a support, having at least one exposure head, which is moved above the support along a guiding axis in the X direction, and the guiding axis and/or the support are moved in the Y direction, having a control system, by which a traversing movement of the at least one exposure head is operated for exposing the at least one image of the recording medium and/or the recording medium, wherein the position of the recording medium and/or the position of the at least one image on the recording medium is acquired with a single linear image acquisition device, which extends in the X direction.

2. Method according to claim 1, wherein the support is scanned for the at least one recording medium by the single linear image acquisition device by a traversing movement along the recording medium and the position of the recording medium and/or the position of the at least one image on the recording medium is detected and evaluated and then the at least one exposure head is operated to adapt to the detected actual position of the recording medium and/or of the at least one image for exposing the recording medium and/or the at least one image.

3. Method according to claim 1, wherein after acquisition of the complete image of the recording medium and/or of the at least one image on the recording medium, the detected actual position is compared with the stored target position and a correction of the target position to the detected actual positions is calculated and operated for the next exposure process.

4. Method according to claim 1, wherein, after acquisition of the complete image of the recording medium and/or of the at least one image on the recording medium, the detected actual position is compared with the stored target position and scaling differences are detected and then a correction of the detected actual position is calculated and operated for the next exposure process.

5. Method according to claim 1, wherein, after acquisition of the complete image of the recording medium and/or of the at least one image on the recording medium by the linear image acquisition device, individual regions are determined and selected, which during subsequent exposure by the at least one exposure head are not exposed with scaling, but are only adapted in position and angle.

6. Method according to claim 1, wherein IR radiation and/or homogeneous visible LED radiation is used for acquisition of the complete image.

7. Exposure device for exposing at least one stored image on a light-sensitive recording medium, having at least one exposure head, which is moved along a guiding axis in the X direction at least with a traversing movement larger than a light-beam sending field of the at least one exposure head, having a support, on which the at least one recording medium is positioned, and having a control system, by which the guiding axis and/or the support is moved towards one another in the Y direction, wherein at least one linear image acquisition device is provided, which extends in the X direction and is assigned and oriented on the support for acquiring a complete image.

8. Exposure device according to claim 7, wherein the single linear image acquisition device extends at least along an orientation in the X direction over the complete support.

9. Exposure device according to claim 7, wherein the linear image acquisition device is positioned on the guiding axis.

10. Exposure device according to claim 7, wherein the linear image acquisition device is provided on a linear axis, which is moved independently of the guiding axis in the Y direction to the support.

11. Exposure device according to claim 7, wherein the linear image acquisition device is assigned fixed or moved to a housing opening of a housing of the exposure device and the support is moved out at least partially from the housing opening of the housing.

Description

[0018] The invention and further advantageous embodiments and variants thereof are described and explained in more detail hereunder, on the basis of the examples shown in the drawings. The features that can be seen from the description and the drawings can be applied according to the invention individually, or several together in any combination. The figures show:

[0019] FIG. 1, a simplified, partial schematic representation of an exposure device,

[0020] FIG. 2, a schematic view of an alternative embodiment of the exposure device in FIG. 1,

[0021] FIG. 3, a perspective partial view of a further alternative embodiment of the exposure device according to FIG. 2, and

[0022] FIG. 4, a perspective view of a further alternative embodiment of the exposure device in FIG. 1.

[0023] FIG. 1 shows an exposure device 11, schematically simplified and only partially. This exposure device 11 comprises a support 12 for one or more recording media 14. These recording media 14 are in particular photographic templates for printed circuit boards and other objects that use phototechnical structures as part of the production process. In particular, resist-coated panels, UV films, solder resists, red-sensitive, orthochromatic films or masks may be provided as recording media. Exposure devices of this kind operate as so-called direct exposure systems. The support 12 of the exposure device 11 is provided on a machine main frame, which is not shown in more detail. The support 12 may for example be configured as a vacuum table, so that after placing and aligning the recording medium 14, a vacuum is applied, to fix the recording medium 14 to the support for exposure. Assigned to the support 12, especially above the support 12, at least two exposure heads 16, 17 are provided, which are configured to be moveable in the X direction along a guiding axis 18. The guiding axis 18 is moveable in the Y direction along the support 12 with a sliding arrangement 19. The sliding arrangement 19 and the exposure heads 16, 17 are controlled by a control device, which is not shown in more detail. The control device of the exposure device 11 is software-controlled. The displacement of the sliding arrangement 19 in the Y direction and of the exposure heads 16, 17 in the X direction takes place under software control by means of drives operating in translation, which are known per se.

[0024] For exposing the recording medium 14 or the at least one image 21 provided thereon, various exposure strategies may be used. For example, the recording medium 14 is divided up into columns S1, S2, . . . S8. Exposure preferably takes place by columns, wherein two selected columns spaced apart are always travelled over simultaneously by the exposure heads 16, 17 assigned to them and are exposed thereby. The column width preferably corresponds to the width of a light-beam sending field LA or LB of the respective exposure head. Exposure of a complete recording medium 14 of this kind is described in more detail in DE 20 2016 01 967 U1, to which reference is made in its entirety.

[0025] Before exposure begins, the position and/or orientation of the at least one recording medium 14 on the support 12 are detected. For determining a position and/or orientation of the recording medium 14 on the one hand and/or the position and/or orientation of at least one image 21 on the recording medium 14 on the other hand, at least two, preferably three or more measuring points of the recording medium 14 and/or of the at least one image 21 are acquired. This acquisition takes place with at least one linear image acquisition device 25. This at least one linear image acquisition device 25 extends in the X direction. By a traversing movement of the sliding arrangement 19 in the Y direction, the at least one linear image acquisition device 25 can be moved all the way along the support 12 and the whole two-dimensional extent of the recording medium or media 14 can be acquired.

[0026] In the exemplary embodiment according to FIG. 1, a single linear image acquisition device 25 is provided. This may for example be configured in the form of a scanning strip, which acquires an image line-by-line from the recording medium 14 during the traversing movement in the Y direction. The acquired data are assembled into a complete image by means of a frame-grabber card. The position and/or orientation of the at least one recording medium 14 and/or the position of the at least one image 21 can be acquired thereby. Preferably the recording medium 14 has at least two, preferably three, measuring points, in order to acquire the X/Y position of the recording medium 14 on the support 12 and the orientation of the recording medium 14 on the support 12. A similar situation applies to the images 21.

[0027] The linear image acquisition device 25 may comprise LED illumination, to allow shadow-free illumination of the recording medium 14 for image acquisition. The image acquisition device may have chips, especially CMOS chips, for high-speed image recording. Alternatively, IR radiation may be provided. A combination may also be provided.

[0028] In the exemplary embodiment according to FIG. 1, the linear image acquisition device 25 is provided on the sliding arrangement 19. Alternatively, the sliding arrangement 19 may be assigned a separately controllable sliding arrangement 19, which holds the linear image acquisition device 25 exclusively. A scanning motion of the linear image acquisition device 25 can therefore be activated independently of the exposure heads 16, 17.

[0029] FIG. 2 shows a schematic view of an alternative embodiment of the exposure device 11 in FIG. 1. In this alternative embodiment the linear image acquisition device 25 is fastened directly on the guiding axis 18. This linear image acquisition device 25 may be provided laterally, i.e. opposite the exposure heads, on the guiding axis 18, as shown in FIG. 2.

[0030] Alternatively, the linear image acquisition device 25 may also be positioned under the guiding axis 18, i.e. between the guiding axis 18 and the support 12. This embodiment is shown for example in FIG. 3. In the embodiment according to FIGS. 2 and 3, the exposure heads 16, 17 and the linear image acquisition device 25 are moved together by means of the guiding axis 18.

[0031] A further alternative embodiment of the exposure device 11 is shown in perspective in FIG. 4. This exposure device 11 comprises a housing 13 with a machine main frame, on which the support 12 is held moveably. On the operator side, a housing opening 15 is provided in the housing 13, through which the support 12 can be moved out at least partially for placement of at least one recording medium 14. The support 12 can also be moved out of the housing 13 for removing the at least one recording medium 14 from this support 12. The linear image acquisition device 25 can be fixed on an upper front end of the housing opening 15 of the housing 13. This makes it possible for the position and/or orientation of the recording medium 14 to be detected already during inward travel of the support 12 into the housing 13. Moreover, the position and/or orientation of the at least one image 21 can be detected. Preferably a complete image can be acquired from the at least one recording medium 14 present on the support 12.

[0032] After the support 12 has been introduced into the housing 13, the exposure process can be started in a processing or exposure position to the at least one exposure head 16.

[0033] Alternatively, it may be provided that the image acquisition device 25 is moveable at least partially in the Y direction, so that starting from the housing opening 15 this can be moved at least partially into the interior of the housing. As a result, by means of a relative movement between the image acquisition device 25 and the support 12, the acquisition of a complete image of the at least one recording medium 14 and/or of the at least one image 21 on the support 12 also becomes possible.

[0034] The linear image acquisition device 25 is preferably selected in length so that it extends over the full width of the support 12, thus in the X direction, at right angles to the traversing movement of the support 12. A scanning field 26 can be created thereby, which extends linearly or in the form of a narrow strip over the complete support 12.

[0035] For the exposure device 11, a control system 27 is provided, which comprises an operator interface 28 and optionally a display 29. The individual program steps and procedures can be input and/or started via this.