T 126/09 – Selected With Care

This decision deals with the refusal of an application by the Examining Division (ED), on the ground of lack of novelty with respect to document D4.

Claim 1 before the Board read (in English translation):

Arrangement for carrying out surgical laser treatments of the cornea, the arrangement being adapted to emit pulsed treatment radiation with a wavelength of between 340 nm and 360 nm and a pulse duration in the femtosecond range, wherein the pulse energy of the treatment radiation is between 0.1 nJ and 5 μJ, preferably at most about 10 nJ.

Here is the outcome of the novelty assessment by the Board:

*** Translated from the German ***

[3.1] D4 primarily deals with the determination of the fluence threshold for the fluence threshold for the optical breakdown and the determination of a point at which there is a change of the characteristic curve describing the fluence threshold as a function of laser pulse width for a variety of materials to which laser radiation is applied […]. The lasers used to this aim generally also work in the femtosecond range, with pulse energies that are within the domain cited in claim 1 […]. In the second paragraph of column 3 the wavelength range from 200 to 1000 nm is cited.

Under “Example 3” […] the (in vitro) examination of cornea tissue with a wavelength if 770 nm is also disclosed. D4 does not mention any reasons for the choice of the wavelength value, nor does it refer to other wavelengths [suitable] for this material.

[3.2] Thus the subject-matter of claim 1 differs from D4 only by the claimed wavelength range between 340 and 360 nm.

[3.3] Therefore, the distinguishing feature concerns the selection of a sub-range within the broader parameter range disclosed in D4. As far as the assessment of novelty is concerned, the established case law of the Boards of appeal (see, e.g. T 198/84) requires that the following criteria be taken into consideration: the selected sub-range has to be (a) narrow, which is doubtlessly the case here (20 nm) and (b) sufficiently far removed from the known boundary values and examples, respectively, which is also the case here. Finally, it must (c) not be an arbitrary selection without there being a new technical teaching. This criterion is also fulfilled here, for the following reasons:

On the one hand, the lower limit of the selected wavelength range ensures that the treatment radiation penetrates deep enough into the cornea (as a rule, the shorter the wavelength, the lower the penetration depth; the cornea becomes significantly transmissive at about 300 nm). On the other hand, the upper limit avoids the radiation to have undesirable secondary effects on other tissues of the eye, in particular the retina […]. In this context it is important to consider the transmissivity of the lens under the cornea, which significantly increases below about 400 nm, so that radiation of greater wavelength can reach the rear parts of the eye, as far as the retina, almost without being attenuated (mehr oder weniger ungehindert), and can damage them. The selected (narrow) wavelength range from 340 to 360 nm is sufficiently remote from both limits (300 and 400 nm, respectively) so as to allow for patient specific variations of those limits of transmissivity.

[3.4] The technical effect related to the upper boundary value cannot be considered to be “speculative” (as stated in point [1.3] of the decision refusing the application) because it can be clearly seen from the relevant technical literature that the transmissivity of the human eye lens significantly increases above 400 nm.

It is further clear from point [1.4] of the decision refusing the application that the ED considered it mandatory that said technical effects were found in the selected sub-range exclusively. However, the Guidelines for examinations cited in this context (C-IV 9.8, version December 2007) only make the (positive) statement that criterion (c) is met if the technical effect occurring in the selected sub-range does not occur in the whole of the known range (see also T 198/84 [7]). This does not allow to derive the requirement construed by the ED. As correctly stated in the statement of grounds of appeal […], such a requirement would hardly ever be met and is, therefore, out of touch with reality (realitätsfremd).

[3.5] Thus the claimed wavelength range is not an arbitrary cut-out of the range known from D4 and, therefore, not lacking novelty. Under these circumstances, it may remain open whether the lasers mentioned in general terms in D4 are “arrangements for carrying out surgical laser treatments of the cornea” within the meaning of claim 1.

[3.6] As none of the other documents of the state of the art discloses the claimed combination of features, the subject-matter of claim 1 is novel within the meaning of A 54(1) and (2).

To read the whole decision (in German), click here.

The file wrapper can be found here.