Ex Parte Wheatley et al

Patent Trial and Appeal Board

Mar 18, 2016

12918549 (P.T.A.B. Mar. 18, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
12/918,549 12/10/2010
32692 7590 03/22/2016
3M INNOVATIVE PROPERTIES COMPANY
PO BOX 33427
ST. PAUL, MN 55133-3427
FIRST NAMED INVENTOR
John A. Wheatley
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www .uspto.gov
ATTORNEY DOCKET NO. CONFIRMATION NO.
63798US006 8893
EXAMINER
GYLLSTROM, BRYON T
ART UNIT PAPER NUMBER
2875
NOTIFICATION DATE DELIVERY MODE
03/22/2016 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address( es):
LegalUSDocketing@mmm.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE
THE PA TENT TRIAL AND APPEAL BOARD
Exparte JOHN A. WHEATLEY, 1
Michael A. Meis, Rolf W. Biemath, Philip E. Watson, and
Tao Liu
Appeal2014-002389
Application 12/918,549
Technology Center 2800
Before CATHERINE Q. TIMM, MARK NAGUMO, and
WESLEY B. DERRICK, Administrative Patent Judges.
NAGUMO, Administrative Patent Judge.
DECISION ON APPEAL
John A. Wheatley, Michael A. Meis, RolfW. Biemath,
Philip E. Watson, and Tao Liu ("Wheatley") timely appeal
under 35 U.S.C. § 134(a) from the Final Rejection2 of claims 1-31, which
are all of the pending claims. We have jurisdiction. 35 U.S.C. § 6.
We reverse.
1 The Real Party in Interest is listed as 3M Company. (Appeal Brief,
filed 21June2013 ("Br."), 2.)
2 Office Action mailed 25 January 2013 ("Final Rejection"; cited as "FR").
Appeal2014-002389
Application 12/918,549
A. Introduction3
OPINION
The subject matter on appeal relates to thin hollow backlights
(Spec. 5, 11. 6-7) for, e.g., liquid crystal display ("LCD") panels (id. at 3,
11. 3--4).
Generally, backlights are said to comprise light generation surfaces,
such as LEDs, and optical elements arranged to "produce an extended- or
large area- illumination surface or region, referred to as the backlight output
surface." (Id. at 8, 1. 29 to 9, 1. 1.) The '549 Specification defines two
categories of backlights, based on the position of the light sources relative to
the output area. In edge-lit backlights, the light sources are disposed along
an outer border of the output area, often shielded from view by a frame or
bezel that borders the output area. (Id. at 1, 11. 17-21.) A light-guide is
typically a clear, solid, thin plate that transports or guides light from the
sources across the entire width of the light guide. (Id. at 11. 23-27; and at 9,
11. 19-22.) Extraction structures are provided on the surface of the light
guide to redirect some of the guided light out of the light guide toward the
output area of the backlight. (Id. at 1, 11. 27-31; and at 9, 11. 22-24.) In
direct-lit backlights, the light sources are disposed directly behind the output
area of the backlight, and a strong diffusing plate is positioned between the
3 Application 12/918,549, Backlights having selected output light flux
distributions and display systems using same, filed 19 December 2010, as
the national stage of PCT/US09/34369, filed 18 February 2009, and
claiming the benefit of 61/030,767, filed 22 February 2008. We refer to the
'"549 Specification," which we cite as "Spec."
2
Appeal2014-002389
Application 12/918,549
light sources and the output surface to spread light over the output area.
(Id. at 2, 11. 13-17.)
Solid light guides are said to have been used for the thinnest
backlights thus far. (Id. at 9, 1. 16.) Although they are said to provide
efficient low loss transport of light and specular [mirror-like] reflections at
the top and bottom surface of the light guide via total internal reflection
("TIR") (id. at 11. 19-21 ), they are said to be expensive and heavy, and
output light uniformity is difficult to obtain for large displays. (Id. at 9,
11. 25-27.) In particular, the Specification teaches that transforming high
intensity point sources of light into the large output area of the backlight can
cause uniformity problems in both direct-lit backlights as well as edge-lit
backlights. (Id. at 11. 29-30.)
According to Specification, these problems can be reduced
significantly by providing a hollow light guide that also provides significant
lateral transport of light. (J d. at 9, 11. 31-3 2.) In the words of the
Specification,
We propose replacing the solid light guide with air, and the
TIR surfaces of a solid light guide with high efficiency low-
loss reflectors ... Lateral transport of light can be initiated
by the optical configuration of the light source, or it can be
induced by an extensive recycling of light rays in a cavity
that utilizes low loss reflectors.
(Id. at 10, 1. 28, to 11, 1. 2.)
Generally, the inventive backlights comprise a partially transmissive
front reflector and a back reflector that together form a hollow light
recycling cavity. (Id. at 3, 11. 17-19.) At least a portion of the back reflector
is non-parallel to the front reflector. (Id. at 11. 19-20.) Of critical
3
Appeal2014-002389
Application 12/918,549
importance in this appeal, the backlight includes at least one semi-specular
element disposed within the hollow light recycling cavity. (Id. at 11. 20-22.)
One or more light sources are configured to emit light into the hollow light
recycling cavity over a limited angular range. (Id. at 11. 23-24.)
The Specification explains that these features are thought to control a
number of parameters that affect the output light flux distribution of the
backlight. (Spec. 6, 11. 1-9.) In the cavity, light that travels in directions
such that at least a portion of the light can be transmitted through the front
reflector is said to travel in the "transmission zone." (Id. at 6, 11. 29-30.)
Light that travels in directions such that the light is not likely to be
transmitted through the front reflector is said to travel in the "transport
zone." (Id. at 11. 15-17.) The rate of conversion of light from the transport
zone to the transmission zone is said to be controlled in part by adjusting the
ratio between the length L of the backlight to the thickness H of the
backlight. (Id. at 7, 11. 1-8.) In particular, the thickness H can be adjusted
by making at least a portion of the front and back reflectors non-parallel to
one another. (Id. at 11. 9-10.)
According to the Specification, the semi-specular element
can provide the hollow light recycling cavity with a balance
of specular and diffuse characteristics, the elements having
sufficient specularity to support significant lateral light
transport or mixing within the cavity, but also having
sufficient diffusivity to substantially homogenize the angular
distribution of steady state light within the cavity, even when
injecting light into the cavity only over a narrow range of
angles.
(Id. at 8, 11. 8-13.)
4
Appeal2014-002389
Application 12/918,549
The Specification teaches that "[a]s used herein, the term 'semi-
specular reflector' refers to a reflector that reflects substantially more
forward scattering than reverse scattering." (Id. at 29, 11. 12-13.) In a
similar way, the term 'semi-specular diffuser' "refers to a diffuser that does
not reverse the normal component of the incident ray for a substantial
majority of the incident light, i.e., the light is substantially transmitted in the
forward (z) direction and scattered to some degree in the x and y directions."
(Id. at 29, 11. 14-17.) Thus, "semi-specular reflectors and diffusers
(collectively referred to as semi-specular elements) direct the light in a
substantially forward direction." (Id. at 11. 17-18.)
Claim 1 is representative of the dispositive issues and reads:
A backlight, comprising:
a partially transmissive front reflector and
a back reflector
that form a hollow light recycling cavity comprising an
output surface, wherein
at least a first portion of the back reflector is non-parallel
to the front reflector;
at least one semi-specular element disposed within the
hollow light recycling cavity; and
one or more light sources disposed to emit light into the
hollow light recycling cavity, wherein the one or more
light sources are configured to emit light into the hollow
light recycling cavity over a limited angular range.
(Claims App., Br. 11; some indentation, paragraphing, and emphasis added.)
5
Appeal2014-002389
Application 12/918,549
The Examiner maintains the following grounds of rejection4 :
A. Claims 1-5, 7-13, 15-18,20-26,and31 standrejectedunder
35 U.S.C. § 102(b) in view of Chang. 5
Al. Claims 6, 14, 19 and 27-30 stand rejected under
35 U.S.C. § 103(a) in view Chang.
B. Discussion
Findings of fact throughout this Opinion are supported by a
preponderance of the evidence of record.
Claimed subject matter is anticipated if a prior art reference provides a
description of an embodiment that meets each and every element recited in
the claims. E.g., In re NTP, Inc., 654 F.3d 1279, 1302 (Fed. Cir. 2011)
("It is axiomatic that for anticipation, each and every claim limitation must
be explicitly or inherently disclosed in the prior art." (citations omitted)).
Wheatley urges the Examiner erred in finding that Chang describes "a
semi-specular element disposed within a hollow light recycling cavity" as
required by claim 1. (Br. 6, 1. 21 ).
The Examiner holds that "the plain meaning of a semi-specular
element would be an element which has some characteristics of a specular
reflector and some characteristics of a diffuse, or lambertian reflector."
(FR 10, 11. 2--4.) "As such," the Examiner continues, "virtually all reflectors
are semi-specular; assuming that at least a miniscule portion of forward
scattered light is present." (Id. at 11. 7-9.)
4 Examiner's Answer mailed 4 October 2013 ("Ans.").
5 Shao-Han Chang, Backlight module, U.S. Patent Application Publication
20071017167 6 A 1 (2007).
6
Appeal2014-002389
Application 12/918,549
The Examiner finds that Chang, Fig. 2, reproduced injra"shows light
which is at least semi-specularly reflected (that is, reflected forward) to
show that Chang certainly anticipated reflectors which are 'semi-specular' in
nature." (FR 10, 11. 9-11.)
216&
23
I
{Chang Fig. 2 shows backlight module 20[6] with light paths from light
sources 22 to central protrusion 214, which defines reflective surfaces 2142
and 2144, which reflect light to diffusion plate 23. (Chang [0020]-[0022].)}
The Examiner finds that Chang, paragraph 31, further supports this
finding. (FR 10, 11. 11-12.) Chang [0031] reads in most relevant part:
It is to be understood that the present backlight module may
further include a highly reflective film deposited on the two
reflective surfaces of the protrusion and the upper and bottom
reflective units, for improving the light
(Chang 3 [0031 ]; emphasis added.)
The Examiner's interpretation of the term "semi-specular element" is
flawed in several respects. Initially, although commendably seeking to give
the term the broadest reasonable interpretation during examination, the
6 Throughout this Opinion, for clarity, labels to elements are presented in
bold font, regardless of their presentation in the original document.
7
Appeal2014-002389
Application 12/918,549
Examiner has neglected to consider the meaning provided in the
Specification. As discussed supra, semi-specular elements "direct the light
in a substantially forward direction." (Spec. 19, 11. 17-18; emphasis added.)
The Examiner has not directed our attention to any inconsistency in the
Specification that might indicate that the definition provided in the
Specification should be discounted. Furthermore, the attempt in the
Examiner's Answer (Ans. 10-12) to expand the meaning of the term
"semi-specular" to include "at least a miniscule portion of forward scattered
light" is not supported by any credible evidence that the prefix "semi-"
would have been understood by persons skilled in the art to include
"miniscule" amounts of forward scattering. In sum, the Examiner has not
come forward with credible evidence or reasoning to overrule the definition
provided by the '549 Specification and to characterize, reasonably, the
central protrusion covered with a highly reflective coating in Chang's
backlight assembly as a "semi-specular element."
We therefore reverse the rejection for anticipation in view of Chang.
The Examiner makes no findings regarding the purported obviousness of the
dependent claims that cure the defects of the rejection for anticipation.
Accordingly, we also reverse the rejection for obviousness.
C. Order
It is ORDERED that the rejection of claims 1-31 is reversed.
REVERSED
8