T 1001/17 23-06-2022

I. The opponent filed an appeal against the interlocutory decision of the opposition division to maintain the patent on the basis of auxiliary request VII as filed during the oral proceedings before the opposition division.

II. Oral proceedings before the board took place on 23 June 2022.

III. The appellant (opponent) requested that the decision be set aside and that the patent be revoked.

The respondent (patent proprietor) requested that the appeal be dismissed.

IV. Claim 1 of auxiliary request VII reads as follows.

"An X-ray device comprising:

a camera (20) to image an object and output the image (42) of the object;

a display member (30) to display the image (42) of the object and an image (43) of an X-ray irradiation region of the object such that the image (43) of the X-ray irradiation region overlaps the image (42);

an X-ray generator (1) for generating X-rays;

an X-ray irradiation region controller (10) disposed in front of the X-ray generator (1) configured to control the X-ray irradiation region of the object to which the X-rays are irradiated,

said X-ray irradiation region controller (10) comprising an aperture (7) to control an irradiation passage and the irradiation region of the X-rays;

an input member (21) for enabling a user of the X-ray device to input a variety of instructions for operations to perform X-ray imaging, wherein said input member is adapted to enable the user to change size and position of the image of the X-ray irradiation region; and

a control member (50) is adapted to enable the X-ray irradiation region controller to control the X-ray irradiation region, based on the image of the object and the image of the X-ray irradiation region displayed in the display member;

wherein the camera (20) is mounted to an outside of the X-ray irradiation region controller (10) to image the object present in the direction in which the X-rays are irradiated,

wherein the camera is mounted to an outside of an end of a length of the X-ray irradiation region controller, from which the X-rays are discharged to the outside from the X-ray irradiation region controller, to image at least a portion of or the entire shape of the object."

Claim 7 of auxiliary request VII reads as follows.

"A method for controlling an X-ray irradiation region comprising:

displaying an image (42) of the object obtained by a camera (20) of an X-ray device in a display member (30) of the X-ray device, said X-ray device comprising an X-ray generator (1) for generating X-rays, and an X-ray irradiation region controller (10) disposed in front of the X-ray generator (1) and to control an X-ray irradiation region of the object to which the X-rays are irradiated, said X-ray irradiation region controller (10) comprising an aperture (7) to control an irradiation passage and the irradiation region of the X-rays, wherein the camera (20) is mounted to an outside of the X-ray irradiation region controller (10) to image the object present in the direction in which the X-rays are irradiated, wherein the camera is mounted to an outside of an end of a length of the X-ray irradiation region controller, from which the X-rays are discharged to the outside from the X-ray irradiation region controller, to image at least a portion of or the entire shape of the object;

displaying an image (43) of the X-ray irradiation region in the display member such that the image (43) of the X-ray irradiation region overlaps the image (42);

changing size and position of the image of the X-ray irradiation region; and

controlling a region of the object to which X-rays are irradiated, based on the image of the X-ray irradiation region displayed in the display member."

V. The following documents are referred to in this decision.

E1 US 5,539,798

B1 US 7,494,276

B2 DE 10 2005 036 852 A1

B3 DE 101 18 183 A1

VI. The arguments of the appellant may be summarised as follows.

Admissibility of the appeal

The statement of grounds set out the reasons why the patent should be revoked. Hence, the appeal was admissible.

Admittance of the objections relating to Articles 54, 83, 123(3) and 123(2) EPC and documents B1 to B3

The opposition had been based on the grounds pursuant to Article 100(a), (b) and (c) EPC. Hence, the objections under Articles 54, 83, 123(2) and 123(3) EPC did not relate to new grounds for opposition. The objections were justified, since the patent as maintained had to meet all the requirements of the EPC. They could not have been filed earlier, since the feature that the camera was mounted to the outside of the collimator, which gave rise to some of the above objections, had been added only in claim 1 of auxiliary request VII, which had been filed during the oral proceedings before the opposition division.

Extension of protection conferred - Article 123(3) EPC

The addition of the term "image of the" in line 20 of claim 1 extended the protection beyond the scope of claim 1 as granted.

The image of the X-ray irradiation region could not be equated with the X-ray irradiation region itself. Hence, the subject-matter defined by claim 1 of auxiliary request VII was broader than the subject-matter of claim 1 as granted because it no longer included the statement that the input member enabled the user to change the size and position of the X-ray irradiation region.

Furthermore, the change of the size and position of the image of the X-ray irradiation region on the display did not necessarily mean that the actual X-ray irradiation region was changed, too. The causal link between the change of the image of the X-ray irradiation region and the change of the X-ray irradiation region, which was present in claim 1 as granted, had been eliminated by the deletion of the term "in that".

The same reasoning applied to claim 7.

Thus, claims 1 and 7 of auxiliary request VII did not meet the requirements of Article 123(3) EPC.

Added subject-matter - Article 123(2) EPC

The feature "the input member is adapted to enable the user to change size and position of the image of the X-ray irradiation region" was not disclosed in the application as originally filed. It was merely disclosed that the user was able to change the size and position of the X-ray irradiation region.

The passages cited by the respondent (page 13, line 24 to page 14, line 1 and page 4, lines 23 to 31) did not support the above-mentioned feature either.

Hence, claims 1 and 7 included added subject-matter.

Sufficiency of disclosure - Article 83 EPC

The feature "the camera is mounted to an outside of the X-ray irradiation region controller to image the object present in the direction in which the X-rays are irradiated" of claim 1 was not disclosed in a manner sufficiently clear to be carried out by the person skilled in the art. If the camera was mounted to the outside of the collimator, there was always a parallax between the camera axis and the axis of the X-ray radiation. The camera could thus not image the object in the same direction as the X-ray irradiation. Due to these contradictory requirements, the subject-matter of the claim was not achievable.

Furthermore, it was not possible to mount the camera to the outside of an end of a length of the collimator, since an end of a (two-dimensional) length was a (one-dimensional) point which did not have an outside or inside. Figures 1 and 2 of the patent disclosed neither a length nor an end of a length. Since the person skilled in the art was not taught at which position of the collimator the camera should be placed, the invention could not be carried out.

Hence, the invention defined in claims 1 and 7 was not disclosed in a manner sufficiently clear and complete to be carried out by the person skilled in the art.

Novelty in view of B1 - Article 54(1) and (2) EPC

B1 disclosed an X-ray device comprising all the features of claim 1 up to the camera mounting position defined in the last paragraph of the claim.

It was possible to derive from Figure 1 of B1 that the camera was arranged on the outside of the housing of the X-ray generator. B1 further mentioned that the camera might be arranged at any location from which it could generate the desired optical image of the object (column 2, lines 35 to 36). A mounting position at the front end of the collimator was therefore implicitly disclosed.

Hence, the subject-matter of claims 1 and 7 lacked novelty over B1.

Inventive step starting from B1 in combination with the common general knowledge of the person skilled in the art or in combination with either of B2 and B3 - Article 56 EPC

Starting from B1, the problem to be solved was to provide a simpler device which was easier to maintain, in that it did not require a mirror in the X-ray irradiation path.

The statement in B1 (column 2, lines 35 and 36) that the camera might be arranged at any location from which it could generate the desired optical image of the object prompted the person skilled in the art to arrange the camera on the outside of the collimator and at the front thereof to solve the problem.

Furthermore, both B2 and B3 disclosed a camera (B2: 29; B3: 41) which was mounted to an outside of an end of a length of the collimator (B2: Figure 3, paragraph [0046]; B3: Figure 1, paragraphs [0031] to [0040]). Thus, B2 and B3 suggested providing a camera position which did not require a mirror in the X-ray generator housing. Therefore, the mounting position of claim 1 was rendered obvious by each of B2 and B3.

Consequently, the subject-matter of claims 1 and 7 lacked an inventive step.

Inventive step starting from E1 in combination with either of B2 and B3 - Article 56 EPC

E1 also did not disclose the mounting position of the camera at the front end of the collimator. The problem to be solved by this document was also to provide a simpler device which did not require any mirror in the X-ray irradiation path. It was rendered obvious by B2 and B3 to arrange the camera at the front end of the collimator.

Hence, the subject-matter of claims 1 and 7 lacked an inventive step.

VII. The arguments of the respondent may be summarised as follows.

Admissibility of the appeal

The appeal was mainly based on new objections referring to new prior-art documents that should not be admitted. Therefore, the appeal was not properly substantiated and should be considered inadmissible.

Admittance of the objections relating to Articles 54, 83, 123(3) and 123(2) EPC and documents B1 to B3

Since the feature that the camera was mounted to the outside of the collimator had already been present in claim 1 of auxiliary request VI filed in the opposition proceedings (point 22 of the decision, feature c)), the new objections under Articles 54, 83, 123(2) and 123(3) EPC could have been raised earlier. Documents B1 to B3 were not prima facie more relevant than the prior art already on file. Their submission was not occasioned by an amendment of the patent as granted and should be considered an unjustified late filing. In particular, the feature concerning the camera position on the outside of the front end of the collimator had already been present in auxiliary request VI, which had been filed (as auxiliary request V) prior to the oral proceedings in opposition. Hence, these objections and these documents should not be admitted.

Extension of protection conferred - Article 123(3) EPC

All the features of claim 1 had to be considered. In particular the feature that the control member is adapted to enable the X-ray irradiation region controller to control the X-ray irradiation region, based on the image of the object and the image of the X-ray irradiation region, rendered it clear that a change in the size and position of the image of the X-ray irradiation region also resulted in a change in the size and position of the X-ray irradiation region. Hence, the latter feature, although not literally recited in the claim, was still implicitly present, and the scope of protection had not been extended in respect of granted claim 1.

Thus, the amendment made to claims 1 and 7 did not infringe Article 123(3) EPC.

Added subject-matter - Article 123(2) EPC

The feature that the user could control the size and position of the second image 45 of the X-ray irradiation region displayed in the second region 44 was disclosed in particular on page 17, lines 5 to 10 in connection with Figure 4.

Hence, claims 1 and 7 met the requirements of Article 123(2) EPC.

Sufficiency of disclosure - Article 83 EPC

Claims 1 and 7 did not require that the recording direction of the camera was identical to the direction of the X-ray irradiation. The feature "the camera is mounted (...) to image the object present in the direction in which X-rays are irradiated" merely stated that the object to be imaged was present in the direction in which X-rays are irradiated.

Furthermore, the interpretation of the definition "outside of an end of a length" in a theoretical and mathematical way was rather unusual and unconventional. The person skilled in the art, presented with the instructions of claim 1, would be able to mount the camera as prescribed, in particular taking into account the additional guidance provided by Figures 1 and 2 and the description on page 11, lines 17 to 25.

Hence, the invention was sufficiently disclosed to be carried out by the person skilled in the art.

Novelty in view of B1 - Article 54(1) and (2) EPC

B1 did not disclose the specific positioning of the camera as featured in the claim. B1 instead suggested positioning the camera in such a way that the "desired optical image" was generated through the shutters of the collimator to avoid errors due to parallax (column 3, lines 44 to 51). Hence, B1 taught against a camera position on the outside of the collimator.

Inventive step starting from B1 in combination with the common general knowledge of the person skilled in the art or in combination with either of B2 and B3 - Article 56 EPC

The appellant's line of argument was based on hindsight, since no incentive could be found in B1 to position the camera at the end of the X-ray irradiation controller such that the optical path of the camera did not pass through the shutter opening.

The laser camera 29 in Figure 3 of B2 referred to by the appellant was used to obtain a three-dimensional profile of the examination area. In detail, the laser scanner provided information about the position of the patient relative to the focal plane. B2 did not refer to the correlation between the image obtained by the laser scanner 28, 29 and the image of the X-ray irradiation region. Hence, this camera provided another functionality compared to the camera according to claim 1. Therefore, the person skilled in the art would not combine the disclosure of B1 with that of B2.

In B3, the image of the camera 41 was not displayed on a display member such that it overlapped with an image of an X-ray irradiation region. The element 47 in B3 referred to by the appellant did not display the actual generated camera image. Hence, the camera 41 served a different purpose compared to the camera in claim 1 or the camera in B1. Therefore, a combination of the disclosures of B1 and B3 would not lead to the features of claim 1.

It followed from this that the subject-matter of claim 1 involved an inventive step over a combination of B1 with the common general knowledge of the person skilled in the art or with either of B2 and B3.

A similar reasoning was applicable to refute the objection concerning claim 7.

Inventive step starting from E1 in combination with either of B2 and B3 - Article 56 EPC

E1 did not motivate the person skilled in the art to alter or improve the positioning of the camera 17.

Based on a similar reasoning as presented in view of the combination of B1 with B2 and B1 with B3, the subject-matter of claims 1 and 7 involved an inventive step.