Ex parte Albaugh et al.

Board of Patent Appeals and Interferences

Jun 26, 1998

08109572 (B.P.A.I. Jun. 26, 1998)

Application for patent filed August 19, 1993. According1
to the appellants, this application is a continuation of
Application 07/624,163, filed December 6, 1990.
1
THIS OPINION WAS NOT WRITTEN FOR PUBLICATION
The opinion in support of the decision being entered today (1)
was not written for publication in a law journal and (2) is not
binding precedent of the Board.
Paper No. 20
UNITED STATES PATENT AND TRADEMARK OFFICE
_____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
_____________
Ex parte VIRGIL A. ALBAUGH
and ROBERT J. URQUHART
_____________
Appeal No. 95-3380
Application 08/109,5721
______________
ON BRIEF
_______________
Before THOMAS, JERRY SMITH and CARMICHAEL, Administrative Patent
Judges.
THOMAS, Administrative Patent Judge.
Appeal No. 95-3380
Application 08/109,572
2
DECISION ON APPEAL
Appellants have appealed to the Board from the examiner’s
final rejection of claims 33 to 46, which are all the claims that
remain in the application.
Representative claim 33 is reproduced below:
33. A method of displaying objects on a computer graphics
system having a display with at least one block of pixels, said
block including at least two pixels therein, comprising the steps
of:
displaying, by the pixels within said block, at least a
portion of a first object;
storing a maximum depth value for the block of pixels
displaying the first object;
computing a single depth value for a second object to be
displayed by at least one pixel in said block; and
determining, in one comparison only between said maximum
depth value and said single depth value, whether all the pixels
in the block will continue to display the first object.
The following reference is relied on by the examiner:
Heckel 4,697,178 Sep. 29, 1987
Claims 33 to 46 stand rejected under 35 U.S.C. § 103 as
being obvious over Heckel alone.
Rather than repeat the positions of the appellants and the
examiner, reference is made to the Brief and the Answer for the
respective details thereof.
Appeal No. 95-3380
Application 08/109,572
3
OPINION
Essentially for the reasons set forth by appellants in the
Brief, we reverse the outstanding rejection under 35 U.S.C. § 103
of claims 33 to 46 on appeal.
In the statement of the rejection at page 3 of the Answer
the examiner recognizes that the depth value of each pixel in the
line segment of Heckel is compared with a depth value stored in a
depth buffer to determine whether or not the pixel is to be
displayed on the screen. The examiner’s position recognizes that
Heckel does not specifically disclose comparing the maximum depth
value of all the pixels within a block to determine the
visibility of the entire block in a single comparison.
The examiner’s reasoning continues by apparently relying
upon the teaching at col. 10, lines 31 to 39 that it would have
been obvious to the artisan within Heckel’s teachings and
suggestions at this location to have performed the operation in
the manner that the examiner recognizes was not specifically
taught in Heckel. Although we appreciate the examiner’s
reasoning here at this portion of the Answer as well as the
example and recognition at pages 5 through 7 of the Answer that
Appeal No. 95-3380
Application 08/109,572
4
there is an apparent logical converse between the express
teachings of Heckel and those associated with the disclosed and
claimed operation, the examiner’s reasoning appears to be
incomplete and misplaced.
Aside from the examiner’s own reasoning and an attempt to
rely upon a teaching at the above noted location in Heckel, the
examiner has not come to grips with the argument made by
appellants between pages 8 and 10 of the Brief that Heckel
expressly teaches comparing the depth information for each pixel
within each identifiable line segment to be displayed with the
depth information for the corresponding pixel in a depth buffer.
Although we would not go so far as to agree with appellants’
assertion that Heckel teaches away from the claimed invention, it
is clear that Heckel does operate solely upon the above stated
principle that a pixel-by-pixel comparison occurs of each pixel
in a line segment of a scene to be displayed with each
corresponding pixel within the depth information stored in a
depth buffer of information already displayed. This is
specifically taught in the summary of the invention beginning at
col. 3, line 59 in at least three locations through col. 6, line
12 and again in the body of Heckel’s disclosure beginning at col.
Appeal No. 95-3380
Application 08/109,572
5
10 through the middle of col. 11 describing the flow chart
operation of Fig. 6.
The “one comparison only” operation in independent method
claim 33 and its corresponding apparatus claim 40 distinguishes
over the individual pixel-by-pixel comparison upon which Heckel
is based. The claimed invention not only requires the storage of
a maximum depth value for a block of pixels actually being
displayed as a first object, but also the computation of a single
depth value (disclosed as a minimum depth value) for a second
object to be displayed, thus permitting the subsequent single
step comparison at the end of independent claims 33 and 40 on
appeal.
Although we agree with the examiner’s basic approach to the
rejection that Heckel may have been modified or could have been
modified so that the artisan would have arrived at the presently
claimed invention, we do not agree that the present claimed
invention would have been obvious to the artisan within 35 U.S.C.
§ 103 on the basis of Heckel and the examiner’s reasoning alone.
Clearly, something more, such as additional prior art, would have
been necessary to convince us that the presently claimed subject
matter would have been obvious to the artisan.
Appeal No. 95-3380
Application 08/109,572
6
Inasmuch as we do not agree with the examiner’s positions
and rejection as they relate to independent claim 33 and 40 on
appeal, we also must reverse the rejection of dependent claims 34
through 39 and 41 through 46. Therefore, the decision of the
examiner rejecting claims 33 to 46 under 35 U.S.C. § 103 is
reversed.
REVERSED
)
JAMES D. THOMAS )
Administrative Patent Judge )
)
)
) BOARD OF PATENT
Appeal No. 95-3380
Application 08/109,572
7
JERRY SMITH )
Administrative Patent Judge ) APPEALS AND
)
) INTERFERENCES
)
JAMES T. CARMICHAEL )
Administrative Patent Judge )
Mark E. McBurney
IBM Corporation
Intellectual Prop. Law Dept., 932
Zip 4054, 11400 Burnet Road
Austin, TX 78758