Ex parte Zhou
Appeal 2010002955; Appl. No. 10/542,910; Tech. Center 2600
May 14, 2012
The application on appeal was directed to an electrophoretic display, a technology commonly used for e-book readers. (See Wikipedia article here for more details.)
A relevant portion of a claim on appeal read:
1. An electrophoretic display panel (1), for displaying a picture corresponding to image information, comprising:FIG. 2 of the application is shown below:
an electrophoretic medium (5) comprising charged particles (6);
a plurality of picture elements (2) ;
a first and a second electrode (3, 4) associated with each picture element ... ; and
drive means (100) ... arranged for controlling the reset potential difference of each picture element to enable particles to occupy the extreme position which is closest to the position of the particles which corresponds to the image information.
During prosecution, the Examiner rejected the claim as obvious using a combination of two references. According to the Examiner, the primary reference taught "the reset potential difference can enable particles to occupy either extreme position."
The Applicant argued that such a teaching was not enough to meet the "closest" limitation:
[The reference] still does not disclose or suggest any relationship between the current position of the particles and their final or extreme position, let alone disclose or suggest controlling ... to enable particles to occupy the extreme position which is closest to the position of the particles which is closest to the image information.In an Advisory Action, the Examiner further explained his reasoning. The reference's use of the reset potential difference allows the particle to occupy either extreme position (i.e., nearest either electrode). Therefore, this same capability also allows the particle to occupy "the extreme position which is closest to the image" – whichever one that happens to be.
On appeal, the Applicant argued that the combination did not teach "controlling the reset potential difference of each picture element to enable particles to occupy the extreme position which is closest to the position of the particles which corresponds to the image information."
The Applicant repeated this argument in the Appeal Brief. In the Answer, the Examiner elaborated on how the particular claim language used to describe behavior allowed the rejection:
[A]pplicant has not positively claimed that the particles actually occupy the extreme position which is closest to the position of the particles which corresponds to the image information;" rather, the applicant has merely claimed that the "drive means" are "arranged" to "enable" the particles to occupy this extreme position. ..[T]he position of the particles can be divided into three possible positions: a position closest to the first electrode, a position closest to the second electrode, and an intermediate position between the two electrodes. ... [T]he position of the particles depends on the potential difference applied to the first and second electrodes (i.e., positively charged particles will migrate to a negatively charged electrode and negatively charged particles will migrate to a positively charged electrode). Thus, it stands to reason that a "drive means" that is "arranged" to "enable" the charged particles to occupy either or both extreme positions can "enable" the charged particles to occupy the extreme position that "is closest to the position of the particles which corresponds to the image information.The Applicant filed a Reply Brief and responded to the Examiner as follows:
[T]here is no need to include "actual" performance in the claims. A device or means which is arranged to perform a patentable function is patentably distinct from another similar device or means which is not arranged to perform this particular function. Accordingly, patentable weight should be given to the related features.The Board briefly summarized the positions of the parties, and then affirmed the obviousness rejection. The Board explained that "[w]e agree with the Examiner since the closest position must be one of the two extreme positions disclosed by the prior art."
My two cents: The way I see it, the Examiner's position was that the primary reference "accidentially" taught the limitation at issue. According to the Examiner, all the claim required is that the voltage drove the charged particles to one end in one scenario and the other end in another scenario. One of those ends is necessarily the one closest to the image.
The Applicant seemed to argue that the reference didn't specifically control the particles in the manner claimed. But did the Applicant t claim the scenarios in enough detail to distinguish?
The Examiner, and the Board, focused on the levels of indirection allowed by "arranged to" and "enable". But the claim did recite that the drive means controlled the voltage to achieve a specific result. Would it have helped if the Applicant had put an active verb such as "select" in the claim, along with some sort of selection criteria?
Was there a distinction here, and the Applicant just didn't capture it? Are there some distinctions that are impossible, or nearly impossible, to express in a claim? And was this one of them?