T 1995/15 - Unusual parameter

Key points

• In this examination appeal, claim 1 was directed to a lighting device wherein "at least 50% of light entering the diffuser exits in an exit pattern regardless of an entrance pattern", i.e. a device claim with a parameter.
• "When relying on an unusual parameter ("at least 50% of light entering the diffuser exits in an exit pattern regardless of an entrance pattern"), the onus is on the appellant to establish novelty over the lightening device of D5 for which, unless otherwise evidenced, there is no reason to doubt that it implicitly fulfils this parameter" 

EPO  T 1995/15 -  link

(a) Main request

Claim 1 reads as follows:
"A lighting device, comprising:
at least a first solid state lighting device; and
at least a first patterned diffuser comprising a plurality of optical features,
(1) said first solid state lighting device positioned relative to said first patterned diffuser,
and (2) the first patterned diffuser configured, such that if said first solid state lighting device is illuminated so that said first solid state lighting device emits light, (a) at least some of said light emitted by said first solid state lighting device enters said first patterned diffuser and exits said first patterned diffuser, in an exit pattern such that a projected pattern of the emitted light would be produced on a structure having a flat surface positioned in the path of the emitted light and substantially perpendicular to the path of at least a portion of the emitted light, and (b) regardless of an entrance pattern of the light that enters said first patterned diffuser, at least 50% of said light entering said first patterned diffuser exits said first patterned diffuser within said exit pattern."

Reasons for the Decision

1. Main Request

1.1 Novelty (Article 54 EPC)

1.1.1 D5 is a print out of the slides which were presented at the SPIE 2006 Annual Conference in San Diego(see page 1 of D5) on 17 August 2006 as evidenced by D6 (pages 1 and 196).

The public availability of D5 before the priority date of the present application was not disputed by the appellant.

1.1.2 D5 discloses on slides 9 to 11, 14, 16 and 18 a lighting device with a green LED from Osram (i.e. a solid state lighting device) which is used with engineered diffusers to provide a rectangular, square or annulus light pattern.

D5 therefore proposes a lightening device having the same lightening element (LED) with the same type of diffuser (engineered diffuser) for achieving the same pattern (rectangular, square) as required by claim 1 and as described in the present application (see claims 2 and 3; page 4, lines 11 and 12; page 9, lines 12 to 16).

1.1.3 The appellant argues that D5 does not explicitly specify that the lightening device comprises a diffuser wherein at least 50% of light entering the diffuser exits in a specific pattern regardless of an entrance pattern, and not every diffuser has this effect.

1.1.4 However, it is an established principle, that the disclosure of a prior art document is not limited to the explicit disclosure only but includes everything that the skilled person would inherently understand when reading the document (see Chapter I.C.4.3 of the Case Law of the Boards of Appeal, 2016, 8th edition).

The Board considers that the engineered diffuser described in D5 would not substantially absorb light, since this would reduce the brightness and efficiency of the lighting element, contrary to the aim explicitly stated in D5 (slides 2 and 18).

Therefore it is considered an inherent property of an engineered diffuser that at least 50% of light entering the diffuser exits in the exit pattern.

Furthermore, it is not apparent that the feature "regardless of an entrance pattern" is a distinguishing feature, when considering that the engineered diffuser of D5 is used together with a collimator, leading to a uniform entrance pattern (see slide 7), and in combination with a fixed, single LED lightening source which provides constantly the same light pattern.

Therefore the lightening element defined in claim 1 cannot be distinguished from the specific lighting element shown in D5.

1.1.5 When relying on an unusual parameter ("at least 50% of light entering the diffuser exits in an exit pattern regardless of an entrance pattern"), the onus is on the appellant to establish novelty over the lightening device of D5 for which, unless otherwise evidenced, there is no reason to doubt that it implicitly fulfils this parameter (see cases cited in the Case Law of the Boards of Appeal, 8th edition, 2016, Chapter I.C.5.2.3).

Neither in the application nor in the written submissions by the appellant has it been explained, why an engineered diffuser, such as described in D5, could be one which does not have the effect that at least 50% of light entering the diffuser exits in the exit pattern regardless of an entrance pattern.

On the contrary, the application as filed on page 4, lines 2 to 3 states that engineered diffusers in general "include optical features such that a substantial portion, e.g., at least 50 %" of the light entering the diffuser exits in an exit pattern regardless of an entrance pattern.

Therefore the application itself makes it clear that any engineered diffuser implicitly fulfils the requirements concerning the amount of light exiting the diffuser defined in claim 1.

1.2 Hence the Board concludes that the subject-matter of claim 1 lacks novelty in view of D5.

2. Auxiliary Request 1

2.1 Novelty (Article 54 EPC)

Claim 1 of auxiliary request 1 corresponds to claim 1 of the main request whereby the exit pattern to be produced has been further defined as being a substantially square shape, a substantially rectangular shape and a substantially hexagonal shape.

The pattern generated by the lightening device of D5 is the same as that defined in claim 1. D5 discloses on slides 10, 15, 16 and 18 a lightening device with engineered diffusers providing a rectangular, square or annulus light pattern.

2.2 The Board therefore concludes that the subject-matter of claim 1 of auxiliary request 1 lacks novelty in view of D5 for the same reasons as claim 1 of the main request.