Sc.he..66e.1, 'V.i1e.c.t-muiUpfe..xe..d l.iqu.id-C.1ybtal. dibpiayb',. SID. Se.mina'l ...... 2. K.G. Clark, I.A. Shanks and N.J. Patterson, SID Digest, p.110 (1979).
CHAPTER
5
CONCLUSION
5.1
A CR)TICAL
5.1.1
re.c.hnique.6
5.1.2
Te.c.hnique.6 60'[ Vibplaying
5.2
IMPACT
5.2.1
Te.c.hnique.6 60'[ Vibplaying
5.2.2
Tec.hniqueb
5.3
SCOPE
5.1
EVALUATION 60'[
Vi6playing
Ge.ne.'[al Patte.'ln6
5.1
Re.bt'l.ic.te.d Patte.'inb
5.3
5.6
FOR
Ge.ne.'[al Patte.'l.M
60'l. DibplaY.£Y1g Rebt'[.(c.ted Patte.'l.nb
FURTHER
STUDY
5.6
5.10
5.12
5.1
5.
CONCLUSION Seve1a!
tebt1ieted
patte1nb
convenUonal new
new
teehniqueb
have
plopoAed,
teehniqueb
techni.queb
i.mplementation 0&
add1eMing
have
been
albO been
06
thebe
the. te.llultll have
been
thebe
new teehniqueb,
3.
in Chaptet
601 dibplaying analylled
teehniqueb cove1ed
in the
and
thei1 .impaet
on the
and
with
the
and deme-titA Mme
the
.in Chapte1
gene1al
and compated
The metit!,
dibeuMed
both
Chapte1.,
expetimental
4.
06 thebe P1aeliea!
veti6ication
A C1.tt.iCa! evaluat.ion
Meld 06 mat1.ix add1eMing
06 and
bcope 601 6u1the'C.wo'C.ka'C.ed.ibcuBed .in th.ib Chaptet.
5.1.
A CRITICAL EVALUATION The new add1eMing
teehniqueb
pwpobed
in thib theb.ib ate
daBiQ{ed
.into two categ01.ieb ab given below : The BAT, HAT, IHAT, IHAT-S3 eateg01Y 06 teehniqueb
and IHAT-S46a!!
601 dibplaljing genetal
unde.-t the
pattetnA
The RPA T-NC and RPA T-PC 6a!l unde.-t the categ01Y teehn.iqueb 601 diAplaljing teAtticted The ooUowing 'lepo'lted ptovide
pe100'C.mance 00 thebe beeUonb. It ib dea1
pattetnA
teehn.iqueb
bette'l
'lewltb
.in beve1al
06
•
.ib e1it.ieally
owm thib evaluaUon
in thi!> Thebib 60'C.dibpfay.ing genemf
;
that
abweU
a'leab, ab eompated
evaluated
in the
the new teehniqueb
ab 'lebt1icted to the
patte'1.nb
conventional
teehni.queb.
5.1.1.
Te.chniquu
60t ViAplaying Gene.tal PattunA
In the analYb.ib 06 the ultimate
Umitb 00'l mat1ix add1eMing 06 tmb
5.2
'lebponding
LCVb
have. bhown
ddplaying
that
c.ompa'le.d to
gene'lal
patte.'lnb,
the. be.le.c.tion 'laUo c.annot
that
06 APT
O'l ZAPT.
be.t 60'lth in the. deve.lopme.nt
Ne.h'ling and
Kme.tz
(1919)
be. imp'lOve.d bigniMc.antly
He.l'lc.e. the
60llowing
a6
obje.c.tive.b we.'le
06 ne.w add'le.Hing te.c.hnique.b :
Re.ducing bupply voltage. 'lequi'le.ment6 ; Obtaining
good b'lightne.H uni60'lmity
06 pixe.l6 ;
Lowe.'ling 06 ha'ldwa'le. c.omple.xity 06 d'live.H • The le.veR 06 buc.c.eM in eac.h 06 thebe a'le.ab ib bumma'lized
All the
new
add'le.Hing
below :
te.c.hnique.b 'le.po'lte.d in thi6
T he.bib 'le.qui'le.
a lowe.'l 6upply voltage. a6 c.ompa..'le.d to that 06 IAPT 60'l we.ll de.6{ne.d 'langeb 06 N • The. b'lightne.H uni60'lmity
06 the. pixe.l6 i6 be.tte.'l in di6playb add'le.Me.d
u6ing BAT, HAT, IHAT and ZHAT-S4 than in IAPT. Only
a pa'ltial
ha'ldwa'le
6uc.C.e.M ha6 bee.n achie. ved in the. 'le.duction
complexity
06 the
ne.w add'le.Ming
technique.b.
06 the.
The. BAT
'le.qui'le.6 le.M ha'ldwa'le. a6 c.ompa'le.d to both IAPT and APT. The. ha'ldwa'le comple.xity
06 HAT ib c.ompa'lable.to
lowe.'l than that
06 IAPT.
with
1. Although
the
that 06 APT and i6 blightly
The. ha'ldwa'le. comple.xity
ha'ldwa'le. c.omple.xity
06 IHA T inC'lea6e.6
06 IHA T-S3 and IHA T -S4
i6 highe'l than that 06 APT, it i6 lowe.'l than that 06 ZHA To The. 6e.ie.ction 'laUo 06 the. ne.w add'leMing
te.c.hnique.6 i6 compa'le.d
with that 06 APT (ab well a6 IAPTl a6 give.n below: Lowe. 'l in BAT; thi6
.(6
not a
6uitaMe. only 60'l smait N.
6e. 'liOu6 p'lOble.m
bince. BAT i6
5.3
L owe1f. in
HAT;
thib
tec.hnique
ib buitable
only
601f.SBE VibplaYb.
Same in IHA T . Lown
in lHAT-S3
and lHAT-S4;
a valu.e c.lobe to that
06 APT ib pOMible.
The new
tec.hniqueb
in Fig.5.1
5.1.2
belec.tion
and Fig.5.2
Techniqueb
ted patte'lnb 'latio
'at
Vibplaqing
objective
the
ib bUmma'libed below:
than
the RPA T -NC
thebe
that
06 the
Rebtticted
Pattetnb
1f.equhementb c.onvent.ional
06 thebe tec.hniqueb
new add'leMing
1.
techniqueb
oneb when The level
601f.dibplaying
the
06
wUh a highe'l
numbe'l
bUc.c.eM
'lebt'lic-
06
beIec.~
belected pixelb
achieved
in thib
a'lea
-
60'l dibplay.i.ng mou Both
voltage
in the CiBe 06 techniqueb
c.onventional
in a c.olumn ib g'le.ate'l
Both
bUpply
'lebpectivellj.
wab to develop than
the
a1f.e c.ompa1f.ed with
The main
tion
1f.at-lob and
and RPA T-PC p'lOpobed in Chapte'l
3 a'le buitable
than one belec.ted pixel pe1f.column.
techniqueb
have
a belection
'latio
independent
06 the
mat'l.i.x b.lze. The belection 06
'laUo 06 thebe techn.i.queb howeve'l dependb on the numbe'l
belected pixelb (W) in each column.
The beIec.tion 1f.at.i.o06 RPAT-Ne .in Chapte1f. when
2)
601f.all
.i.bhighe'l than that
the valueb 06 W. The bele.ction
W = 1 ab in the c.abe 06 peT
The belect.iim
06 FMT (-reviewed
1.atio 06 RPAT-PC
and PRT heviewed ib highe1. than
that
1.atio ib in6.i.nite in ehapte1f. 2). 06 FMT,
when
5.4
+''':
:l ~, :~ :l
--
--j ~ \~~\ :~T II,1 HAT ,1=7 HA =3
IHAT-S3. HAT IHAT-54, ,1=5 0 1:= 4----1=5 1 =6 1=7 N -----. _0 +' ~\ . . ~\\ 0 ~I (j).-o~ ~\ ~ '\ \\1
low
!>.ince
oniy
two
voltage
levelb
a-'le
1equ.i1ed 601 both ww and column add'C.eoo.ingwave60'C.mb.
The
BAT
.i.b weU
bu.ited 60'C.appl.i.cat.i.onb Uke calculato-'l
d.i.&play&lwhe1e.in
b.i.ngle -'lOW 06 alphanume1.i.c. .i.n601mat.i.on .i& to be d.i.&playedJ becaube
a
06 the
60Uow.i.ng advantage& : The low bupply voltage .in p01table The ww
1equhement
make& .it ideal 601 ube
dev.i.ce& •
and column d'l.i.veH can ea&Uy be .integ1ated
.into
the c.alc.ulato'C. c.hip due to the bina1Y natu'C.e 06 add'C.eMing wave60'C.mb.
The 60Uowing d1awbackb 06 BAT
a1e
not
be'C..i.oub&.inc.e
N
.ib bmaU
.in th.ib
appi.i.cat.ion : Lowe1 belect.i.on 1atio 06 BAT a& c.ompa1ed to IAPT. H.i.ghe'C.time
intewalb
to
c.omplete
a
cycle ab c.ompa'C.ed to IAPT.
bJ HAT The HAT ex.tend& BAT 601 h.ighet value& 06 N ; It ib an .inte'C.med.iate btep between the BAT and IHA T.
HA T can be u&ed
QO'l
SBE d.i.&play!>QM. the 6oUowing 'leabOn!>:
Low bUPP{y voltage
1equ.i1ement
Good b'C..ightneM uni60'lm.ity
601 l.i.m.ited value& 06 N ;
06 p.i.xel& ;
The lowe1 &elect.i.on 'lat.i.o 06 HAT a& compa1ed to IAPT i& not a be'C..lOU& p-wbfem he'C.e, c.on&i.de'l.i.ng the
&teep
elec.tw-optic
c.ha1ac.te1.i.&t.i.c.& 06 -SBE V.ibplay&.
5.9
IHA T .ib 06 add'leM
well bu.ited 60'l add'leM.ing mat'l.ix di.bplayb w.ith a la'lge numbe'l
Uneb IN) ab in the
cabe 06 compute'l
te'lm.inalb
babed on both
TN LCVb and SBE V.ibplaYb 60'l the 60llow.ing, 'leabOM : Conb.ide'lable 'leduct.ion .in the bupply voltage ebpec{aUy 60'l la'lge valueb 06 N. IAppUcat.ionb pO'ltab.ie lap-top
compute'lb)
Good b'li.ghtnebb uni.60'lmity
the
above
advantageb
Uke
; 06 pixelb ;
No cOmp'lOmibe .in the belection
Howeve'l
'lequhement
a'le
'lat.ioab
obta.ined
compa'led
at
the
to IAPT •
cObt 06 the
60Uowi.ng
6acto'lb :InC'leabe .in the ha1dwa'le complex.ity
06 column. d'l.ive'lb ;
InC'leabe in the numbe'l 06 t.ime inte'lva1b .in a cycle; 6Ucke'l
d)
can be eliminated
though the
by choob.ing a p'lOpe'l bcanning
bequence.
IHAT-S3 Supply voltage The
bupply
'lequ.i'lement
voltage
w.ide. 'lange 06 N ;
.ib m.in.imum 60'l N lebb than 12 ;
'lequi'lement
.ib lowe'l
than
that
06 IA PT
60'l a
5.70
The. hal[dwal[e. c.omple.xity
ib lowe.1[ ab c.ompal[e.d to lHAT;
T hib I[e.duc.t.ion ib ac.hie.ve.d without
a bigniMc.ant Mc.l[i6{c.e. in the.
be.le.c.tion I[at.io and the. low bupply
voltage. I[e.qu.il[e.me.nt 06 lH A T
Good 6l[ightne.M uY/iool[mdy 00 Pix(Ub •
The. lHA T-S3 lal[ge. numbH
.ib we.U buite.d
601[ dibplaying
06 addl[e.M Une.b and whe.n t.ib
matl[ix
dibplaYb
with
a
c.hobe.n to be. e.ve.n. Th.ib te.c.hn.ique.
c.an be. ube.d 6M TN LCDb and SBE DibplaYb .in vie.w 06 the. advantage.b give.n above.. H owe.ve.1[ the. numbe.1[ 06 time. .inte.l[valb to c.omple.te. a c.yde. .ib bame. ab that
e.)
06 lHA T.
lHA T -S4 The. baUe.nt ne.atUI[e.b and the. appUc.ationb
ab thobe. 06 lHAT-S3.
The. lHAT-S4
06
lHA T -S4 a1e. the. bame.
.ib ube.d whe.n the. value. 06 1 ib c.hobe.n
to be. odd.
5.2.2.
Te.c.hnique.b ~Ot Vi.&ptaqing Re.&hic.te.d The.
RPAT-NC
1e.vie.wed .in Chapte.
1
pl[opobe.d in th.ib the.bib ib a
ab c.ompal[e.d to
l[e.dUc.e.bto PCT whe.n W
=
the. RPA T -PC
genewhed
601m 06 PCT
2. The. numbe. 1 06 be.le.c.te.d pixe.lb .in a c.olumn
a val[iable. in RPAT-NC
mode. (b1ight
Patte.tn&
.ib
in the. c.abe. 06 PCT. The. RPAT-NC
7. WhUe. the. RPAT -NC 1e.bultb .in a negat.ive. c.ont1abt
be.le.c.te.d pixelb pwpobe.d
7
IW)
in
aga.inbt
thib
da'lk
bac.kg'lOund pixe.lb)
in
TN L CD b,
the.bib 1e.WUb in a pOb.iUve c.ont1abt
with dal[k be.le.c.te.dpixe.lb againbt IHight
bac.kg'lOund pixe.lb.
The. baUe.nt 6e.atUI[e.b06 the.be. te.c.hnique.b a'le. give.n be.low :-
mode.
5.11
Selec.tion
1a.t.io .i&.independent
06 the
mat1.ix
bi.ze and jUbt dependb
on the numbe1 06 belec.ted p.ixelb .in eac.h c.olumn. Su.i.table 601 dibplayb whe1e.in the column
06 belected
numbe1
p.ixelb .in eac.h
.ib bmaU ab c.ompa1ed to the numbe1. 06 add1eM Uneb .in the
mat1ix. PObbibWty
06 add.ition
06 dummy
10Wb to
allow
601 a va1.iat.ion in
the numbe1 06 belec.ted pixelb .in eac.h c.olumn. The pObbibleappUc.ationb
06 thebe tec.hn.iqueb a1e dibc.ubbed below : -
a} RPAT-NC Th.ib tec.hnique binc.e the
.i.b well
1e&UU.ing dibplay
be ubed 601 add1eM.ing
bu.ited 601 LCDb babed on Guebt-H obte66ec.t
hab a pObitive
TN LCDb, but
The pObbible applic.ationb lyze16;whe'lein time
waVe60'lmb
a1e to
Qe
d.ibplayed.
c.ont1abt. H oweVe1 they
th.i.b 1ewltb
a1e multit'lac.e
.in a negative
c.ont1abt.
ObC.WObc.opeband logic. ana-
whic.h a'le mObt.l.y bingle Limited
c.an alba
aiphanume1ic
valued
.in601mation
6unc.tionb .in the
601m
06 legendb c.an aiM be d.ibplayed .in wc.happUc.at.ionb ab dibc.ubbed in Chapte1 Thib tec.hnique the
numbe'l
can alba be ubed .in appUc.at.ionb Uke video gameb,
06 belec.ted
06
3.
whe1e.in
pixelb in eac.h c.olumn .ib bmall ab c.ompa1ed to the
mat'lix b-Cze.
bl
RPAT-PC Thib tec.hnique
ib wet! bu.ited 601 TNLCDb
hab a pObit.ive cont1a!Jt although RPA T-NC.
the
!Jelection
binc.e the 1ebulting 1atio i!J towe1 .than
dibplay that
The pOMible applic.at.ion!J a1e the !lame ab tho be 06 RPA T-NC.
06
5.12
The.bUPP£Y
vo£tage.
inC'Le.abe.bwith N.
A
Appe.ndix wite.d
'Le.qui-te.me.nt 06 both
Thib may be. a limiting
ne.w pa'lame.te.'L, i.e.., N
e.q
1601£dibplaying
and
RPAT-PC
6acto'L on the. bize. 06 the. mat'Lix.
hab be.e.n int'lOduce.d Ibe.e., e.qn. 2.20
6.c) and ib ube.d th'r.oughout
60'l compa'ling
RPAT-NC
and
thib' the.bil.>. Thib pa'Lame.te.1. il.> we.ll
the. be.le.ction 'latio
06 the. ne.w add'le.Ming te.c.hnique.b
both ge.ne.'lal and 'le.bt'licte.d patte.'lYlb) with the. maximum
be..£e.C-
tion 'laUO pOb6ible., i.e.~, the. !.>e.le.cUon'laUo 06 APT and IAPT.
In lIummaty,
thi!.>I.>tudy on ne.w add'Le.bbing te.chnique.!.>60'l 'lm!.>'le.l.>ponding
LCVb hab le.d to a be.tte.t unde.ntanding
06 the. pwble.m
Ge.ne.falized addte.Ming te.chnique.lI.
601£ dibplaying
te.d patte.'lnb have. be.e.n de.ve.lope.d
ab a 'le.w£t 06 thib btudy.
ne.w add'le.Ming
te.chnique.b pwpobe.d
both
06 mat'Lix add'le.bbing.
in thib the.!.>ibwill
'lmb -te.l.>ponding LCVb in a wide. 'lange. 06 applicationb. te.c.hnique.1.>hab inC'le.a.be.d the. choic.e. and hade.-066
ge.ne.'Lal and 'Le.l.>t'LicA
numbe.'l 06
e.nhance. the. u!.>e.06 Avai.£ab.i.lity 06 the.be.
pOMible. in the. !.>e.£e.ction
06 an add'le.Ming te.chnique. to wit a give.n application.
5.3
SCOPE FOR FURTHER STUVY Stability
ana.t.y!.>ib06 the. ne.w add'le.bbing te.chnique.b, i.e.., the. e.66e.ct
06 va'Liationb in the. 'le.lative. amplitude.1.>06 the. voltage. le.ve.lb in the. add'Le.Ming wave.60'Lmb on the. be.le.c.tion 'latio will be. 06 p'lactical inte.'le.bt.
In the. c.abe. 06 dibplaying with
lowe.'l ha'ldwa'le. comple.xity
ge.ne.'lalpatte.'lnb
ne.w add'le.M.i.ng te.chnique.1.>
than the. conve.ntional
te.chnique. ib de.l.>i'lab£e..
N e.w add'le.Ming te.chnique. with lowe.'L bupply voltage. 'le.qui'le.me.nt ib de.bi'la.ble. in the. c.abe. 06 dibPfa.ying 'le.l.>t'lic.te.dpatte.'lnb.
5.13
Alth'ough and
the.
e.£e.ct1o-optic
cha'lacte.'l~bt~C.b 'le.qu~'le.d 60'l
g'le.y bcale. a'r.e. .in d.i.'r.e.c.tcon6l, 'Powe.'C.'C.e.ducUon in liquid E£e.ct'Wn Vev-ice,!>, Vat
[571
L.A.Goodman,'
EV-29,
c'C.lj!>tal dibplalj
No.12, pp 1884-1886,
Uquid-c'llj!>tal
[58]
A. R.Kme.tz,
, Uquid
c'C.ljl>tal dibplalj
Re.cO'C.d06 Con6. on Vibpfalj [59]
[60]
A.R.Kme.tz,
di6plalj
p'106pect6 in
Vevice!>, Vol. EV-20,
P.M.AU
and
P.Ple.!>hko,
p'lObpect!> in pp 119-126,
Elect'lOn
pp 954-961,
'Scanning
[61]
J.E.Bigelow c'lljbtal
[62]
et
dibplalj!>',
H .Kawakami
et
c'C.ljl>tal di6plalj', [63]
al,
J.J.Lo1.teije.,
'Cont'lal>t
IEEE ai,
'Mat'lix
SID-IEEE
'Sw.itching
P'lOC. 16t Int. Vi6plalj [64]
M.Schadt, on
the
Lett., [65]
'E66ect!>
M.G.Cla'C.k
and
add1eMed liquid pp
82-83, 1981
06 guel>t ho!>t liquid
K.J .Hanib:m, c'C.lj!>tal device!>',
IEEE
T'C.an!>.
tal di6plaljb',
1974
mat'lix-add'leMed
liquid
pp 22-24,
Vot.Ed-22,
06 tcuibte.d nematic
Vibplalj
60'l multiplexing
06 dielect'C..ic 'lelaxation
pp 691-699,
in
technologlj
Re.cO'ld 06 Biennial
biab voltage!>
pe'1.6pe.ctive.',
06 liquid
Vevice!>,
Re6. Con6., pp 209-212,
elect'lO-opt.ic!> Vot. 41(8),
add'leMing
Con6.
1912
pp 146-155,
optimization
T'lanb. Elect'lOn
Pe'C.!>pe.ctive', IEEE
1913
limitation!>
IEEE T'lanb. E£ect'lOn Vevice.!>, Vol. EV-21,
e.66ect!> and add'C.e.Ming
1974
Vevice!>',
'Uquid-c'lljl>tal
IEEE T1.anb.
1982
d-i!>plctljb - Elect'C.o-optic
te.chnique.!>', RCA Re.view, Vol. 35, pp 613-651,
moduleb',
Con6., pp 50-52, LC mat'lix
1975 liquid 1976
di!>plaljb',
1981 and dual-6'C.equulClj c'C.lj!>taldibplalj!>',
add'C.eMing
Appt. Phljb.
1982. 'Multiplexing
capabWtlj
SIV Int. Sljmp. Vig. Tech.
06
dual-6'l.equency
Pape'l!>,
R7
[66]
H.K.Buc.he.1 e.t al, 'F1e.quenc.y-add1eMed App. PhYb. Lett.,
[67]
M.inMu liquid
[68]
'512-Cha1ac.te1
by two
J.
'Ultimate
A.R.Kme.tz,
RMS-'Ce.bpond.ing Uqui.d-c.1ljbtai ·Vol. EV-26, [69]
J.
The
PhYbic.b and
Ne.h'ling,
limitb
dibpla.yb',
No.5, pp 795-802,
A.R.Kmetzand
06 1e6fe.c.tive. twi.bted
61e.que.nc.y add'le.6!J.ing', SIV 79 Vigebt, 1979
and
7974.
dibplay
Vig. Tec.h. Pape1b, pp 116-117, Ne.h1ing
c.1ybtal 6ield e.6oe.c.t',
Vol. 25, No.4, pp. 186-788,
H060kawa, c.ry6tal
fiquid
60'l
lEEE
mat'lbCOpe. d.i.bpla!!b', SlV Int.Stjmp.
V.i.g.
SIV
Int.
601 non-multiple.x.e.d
S!!mp.
liquid
Tech. Pape.H, pp 772-173,
7979 [79]
'Sh.i.6t Reg.i.bte1 Sequenc.eb',
S.W.Golomb,
Helden-Va!!
Inc.,
San F1anc.i.bco,
C{.(·1.i.601n.i.a, 7967 [80]
R.C.Vixon,
'Sp'lead
bpec.t'lunl
!lYbtemb',
John Wiley
&
Sonb Inc.., pp 87-83,
7976 [81]
B.W.Ma1kb,
'Powe1
conbumpt.i.on
06
mult.i.ple.xed
IEEE T'l.anb. Ele.c.twn Ve.v.i.C.e.b,Vol. EV-29, [82]
H. Kawakam.i.
e.t al,
J.R.Hughe.b,
'Cont1abt
Hhoak.i. Ideno e.t al, LCVb',
[85]
Pwc..
P. Maltebe., mat1ic.eb',
'New
3'ld Int.
!Complex
7982.
pp 28-29,
d.i.bplatjb', SlV
1980
va1.i.at.i.onb .i.n h.i.gh-le.ve.l mult.i.ple.xe.d tw.i.bte.d ne.mat.i.c
l.i.qu.id-c.'lYbtal d.i.bplatjb', lEE 7986. [84]
pp 7278- 7222,
'B1ightne.bb un.i.601m.i.ttj .in 1.i.qu.i.dc1ljotal
Int. S!!mp. V.i.g. Tec.h. PapeH, [83]
Uqu.i.d c.·'UJbtal d.i.bplatjb',
P'lOc.eed.i.ngb, Vol. 733, Pt. I, No.4,
pp 145-757,
d'l.i.ving me.thod appUe.d to la1ge. a1e.a dot-mat1ix
V.i.bplay Reb. Con6. PObt-deadline
pape'l
PV5,
7983.
pola'C.i.ty bequ.enc.eb 60'(. di'Cec.tly d'l.i.ven l.i.quid c.'CYbtal
Pwc.. 7th Int. V.i.bplatj Reb. Con6., pp 139-743,
7987.
Al
APPENDIX
1
PHYSICAL
PROPERTIES
The phybical
OF LIQUID
pwpe 1.tieb that
The tempe1.atu1.e
CRYSTAL
MATERIALS
1.elevant to the
a1.e
dibplay
at which a Uquid c1.ybtal mate1.ial. meftb-6wm
ib the
an iootwpic
tempe1.atu1.e liquid.
at
which
Both the melting
valueb 601. a bingle bubbtance. not 00
neCebba1..ily take tempemtU1.eb.
'langeb 6wm 120°
e in
place
The
'lange OVe'l which
In
at
melting
the
to
ooe
point.
l.iquid c1.yotal
The dea1.ing
mate1.ial
becomeb
and ciea1.ing pointb have well de6i.ned
the cabe 00 mixtU1.eb, the t1.anbit.ion doeb
one
tem'pe1.atu'le,
and
c.lea'ling
the dibplay can ope'late
-30°C
oolid
.
phabe into liquid c1.YbtaUine phabe ib caUed the melting point
appl.icat.ionb
and the
pointb
ove'l a bmaU'lange dete'lmine
the
ubeoul
batibnactcni.£y. The meUing
dea1.ing
the Uquid c'lYbtai mixtU'leb ubenui
but
nO'l
point
mngeb
6wm
point
60°C
to
dibpiaYb.
The motecula1. o1.de1.ing in liquid c1.Ybtalb, 1.ep1.ebented by the dhecto'l ib time
ave'laged
at a macwbcopic
level.
The o'lde'l pa'lamete'l
ib denined ab, {Al.]}
whe1.e
e ib the inbtantaneoub
the p1.e6ened
ave1.age di'lection
The value 06 Scan in tempe 1.atU'le.
deviation and COb2
00 the
e
long
ib the time
molecula1. ave'lage
axib o1.om On
co/e.
1.ange owm 0.3 to 0.7 and it deC1.eabeb with the inc1.eabe
A2
c.] Vie.le.e..t'lie..Anibot'lOPlf The. liquid
e..'lYbtal mate.'lialb have. two die.le.e..t'lie..e..onbtantb, one. along
the. di'le.e..tion 06 the. di'le.e..to'l 1£11) and the. othe.'l pe.'lpe.ndie..ula'lto the. di'le.e..tion 06 the. di'le.e..to'l I~. The. die.le.e..t'lie..aniootwpy
16
d
ib de.6ine.d ab the. di66e.'le.ne..e.
be.twe.en the two didee.t'lie.. e.onMant6, .i..e., 6£
IAl.2)
=
The. mate.'f.ialb with pObitive. die.le.e..t'lie..aniootwpy with
the.i'l long axe.b pa'laUe.l to the
with
ne.gative. die.le.e..t'lie..aniootwpy
IEII > El!
o'lie.nt the.mbe.lve.b
exte. 'lnal elee..t'lie. 6ield, whe'leab thobe. I Ell
value to .it!l 90% -ON
.input
putbe
the !lum 06 td and t 'l •
t'la.in and the
lumed 60'£ de'£.iv.ing the va'£.i~ub'£elat.i.onb .involv.ing the b.inom.ial coe66.i.c.ientt>.
11 +
0'£
II
+
xJ" xJn
"(~}o.(?). =
Subt>t.itut.ing x
=
(A3.9J 1 + .... +( ~ ) x"
t (~)i·
IA3.IOJ
k=O
I .in the above equat.ion IA3.11J
IA3.12J
.i.e.,
IA3.13J
The 60Uow.ing .i.dent.it.i.et>a'£e ut>e6ul .in p'lOv.ing the t>econd te'£m .in eqn.
I
(A3.6J at>equal to 2 : IA3.14J
aJ k (n)
=
k \k -- I I) !1(n
and
bJ
n 2n-1
(A3.15J
Al0 Con.t.i.de.-t
111[(n - kl •••••• 11
en • (n - 1J •••• (n - k +
(A3.161
![(n
k
n • (n - 1) •••••
1]
- kl ..•.••
(n - k + 1)
=
k n
!
1) •••• (n - k
[(n -
k ----I-k---l-1 (n -
n
1)] [(n - klln - k - 1) •••• 1]
lA3.11J
-! -In-- -k-l -In---k-- -1-1-••-••-1--
1!.(n
-
21 •••• [In - 1) -
(k -
1) + 1] •••.. 1 lA3.181
k
lk - 1I!
In - kJ In - k - 1J •••
k
I! _ !!k (nk
lk - 1) ! fln - 1) - lk - 1J]!
l:
k
n
-
=
k
k
1
1
(n -
n
nwm e.quation
+
n~
(n k - 1) ~
lA3.19J
- 1\ ~
lA3.201
k-l
~k (n - 1)
(A4.11 =
n 2n-1
lA3.21 I
Con.t.{de.-t
n
I n-1) ! In-2kl2
L:
k=O
n
(n-1)! k!
L:
_n_!__ k=O k! In-kl!
k
! (n
n
In-1)! nk
k=O
k ! In-kl !
n2
In-kl !
In-1)! [n2
k=O
L:----4L; n
=
2:
k ! In-kl !
k=O
=
n
=
-4
~ L.. k
~~-n
k=O
k!
!
(n-kl!
-
4nk
- kl
+ 4k2]
lA3.22J
! n
+ 4
+
to 4
lA3.231 k !In-kl!
~ k2 ~ -n-
k=O
n
!
k !In-kH
lA3.24J
A71
{.
=
-.{ •
=
{.e.,= Henc.e, n
n
. ! .
LL:
tL
-21(n n.{ 2- k n! +1.{ n-l 22k)2 .,~=+112.2 -')IA3.32 i k-l) - - k).i=O ~ -nn11-1J~ n2n + 4(nIn (In-O 2 12n -- 4 2n 22n-l + 4+ 2n-2 k + 2n-1 11-2.iJ2 n 4 k=O 4 k( k ) + -n1 n= 2n + (k) 4[t - Ik-O (k~11) 2n
t L
E
IA3.31J
) (n-l !!
42:: :2) ] (~) +Z(k::)
(A3.30)
(A3.21J IA3.28 (A3.26) (A3.29 (A3.25J))
(n-l)
3.c.
P'Zoon
On
the
fpUow.ing
.ident.itlj
.ib g.iven
below:
IA3.33)
Subbt.itut.ing 06 the
above
nO'l
A.{and B..{ 6wm eqn. (3.53) and (3.54J 'Zebpec.t.ive1lj ~n the LHS
exp'le6b.ion,
A12
I
L:
t 1:I
.c! If - .( • IA. B.) .c=o11-2.{ =.{ - If-I)! .{ 2
l, ')
A. + B .
.c=O
IA3.34)
.(
.{
But,
I
I: .c=O
It -
11!
It -
= 2
given
matrices.
(VONIVOpp) Alt and Pleshko
Present method
itself.
Further,
so that
mistakes
Hence RMS
any
sign,
of the N/2
rows,
rapidly
small
zero
display.
fig. 1).
choice
Covering
The optical contrast ratio depends listed below for a few values of N and ventional
also
ambiguous
since
binary
'0' to be
the
of opposite
the
row-electrodes.
'V' and
to address
pulses
ensured
a matrix
clear the
addressing
voltage
becomes
the
equivalent
It is also
chose
is adequate
it is clear
N replaced
of
of
electrode
voltage-pattern
can
complementary
number
is automatically
When the
we
of voltage
through
an equal
operation
to
In fact
source
and Ruckmongathan
came
considered
a computer
across
a paper
a similar
simulation
by Clark
multiplexing
analysis,
-1
et al(2)
in which
technique.
they
have
they
By using
conjectured
the
that
is
(5)
!} ] where
q is an integer.
using
binominal
our
mathematical
16-SEGMENT We and
series,
Since a display,
it can
analysis.
ALPHANUMERIC
treat
bottom
N = 2q+l
each
and be
confirms
(2q) denotes
a binominal
q
easily
shown
that
the
conjecture
by Clark
By
coefficient.
(4) reduces
to
(5).
Thus
et al.
DISPLAY
character
plates
are
shown
we did
not
have
a 1702EPROH
was
as in
a 4 x 4 matrix. figure
The
interconnections
on
the
top
3 ••
a standard
character
programmed
to convert
generator the
ASCII
IC for code
addressing from
a key
such board
A'l6
. I
I'l__
;
." ~
•.•....
'_•._'J.:..l~~.;.~.: •. :
c·
a
b Figure 5
Photographs of two alpha-numeric patterns of a TN display panel with (a) parallel polarizers and (b) perpendicular polarizers.
An
Multiplexing
scheme
(or smdll
mdcrix
503
displdYs
Figure 3. The electrode patterns and the mterconnections on the top and bottom ~lates of the display panel.
to the code necessary to address this display. 64 characters
is 64
x
4
x
The total memory required for
4 '" 1024 in the organisation
of the system is given in figure 4.
256)( 4.
The logic circuitry
The block diagram
required to produce
the data for columns is simple and consists only of finding the number of coincidences
of the column data with the addressing
waveform and making a
simple majority decision.
... "
.-""'"
••••••• I ~.'r •. -.."" ... 1."" Figure 4. Block diagram of the display system •
•• Iff • • "i
•• ',"0"
•• iii 0
'I'"
,..
CI• C " ,
f
Photographs of some preliminary twisted nematic displays the basis of this scheme are shown in figure 5. performance
constructed
on
We feel that if the display
is optimized by a suitable choice of materials,
this will be a
convenient method of addressing the displays. ACKNOWLEDGEMENT We are indebted to Prof. s. Chandrasekhar Our thanks are also due to Mr. K. Subramanya help in constructing
the displays.
for several useful discussions.
and to Mr. H. Subramonyam
This work was partially
for
supported by the
Indian Space Research Organization. REFERENCES 1.
P.M. Alt and P. Pleshko, IEEE Trans. EO-2l, 146 (1974).
2.
K.G. Clark, I.A. Shanks and N.J. Patterson, SID Digest, p.110
(1979).
AU
APPENDIX 6.b
Re..pwduc.tion 06 a pape..'l publibhe..d in Pwc.e..e..dingb 06 the.. Soc.ie..ty 6o'l In6o'lmation Vibplay, Vol. 24, No.3, pp.259-262, 1983.
NEW ADDRESSING TECHNIQUES FOR MULTIPLEXED LIQUID CRYSTAL DISPLAYS T. N. Ruckmongathan
and N. V. Madhusudana
Raman Research Institute Bang%re. India
n
Abstract - A binary addressing lechnique(BA for multiplexing liquid cryslal displays (l,CDs) is described. It requires addressing waveforms Wilh only two voltage levels. and leads 10 a naturally dc·free operation. The melhod is suilable only for small mal rices (Ns being displayed. The selection ratio in this case is ,I2(Neq = 9). Photograph 2 shows a single wa'leform along with legend •. The characters are for=ed by a 5x5 dotmatrix, with one row at top and !;.ottom to separate the legends from the background. An addition~1 7 elements are selected in every column. The selection ratio is [,;8/(18-1)]112, (I.e., Neq = 22). The commercial mixture RO-TN 701 is u.ed in the display and the supply voltage is 71.
SID 86 DIGEST·
129
A34 RM.l~N RE£.r •. (Ii lNSTtTU1[
eA;\iL~.Lor,f.; 80
-~::~::~~i~~~~jli:i6:" o JlfUUlJlIlIlIl! _
ROW ~
L-
ROW
1SELECTED
+ (l//iilV
----.1 v ROW ~
iJl
~~(1-1//il}V ·t-{H/IilIV - (1//o)V
--
illMIIJl t-t-ROW N SELECTED
T
•.....•..
NT -1
VVON(rms) =[V2+(V~Iii}2n
J 1/2
(11/il}V- n n n n n r, lJfl,LJUUL nnn (l-lllin~-JUUUWU COLUMN WAVEFORM ~
VOFF(
VjV N _ NUMBER OF ROW n _ NUMBER OF. ELE~E~T 5 T,HE OISPLAyON OFF~ATRIX IN A COLUMN..
rmslfV-V//ii}2+(v:n}2(n-1l]
SUPPLY VOL TAGE
Fig:
2 REPRESENTATIVE OSCILLOSCOPE
130 • SID 86 DIGEST
WAVEFORMS DISPLAY.
t/O/(/O -
OFF:
I
FOR
VON
:
I)
1/2
J 1/2 1/2
:
V (Nl2) S90
ADDRESSING
MULTITRACE
A 35
Photograph
1
Photograph
Impact Since the selection ratio is higher than that of APT, a better contrast can be achieved. The selection ratio' is independent of the total number of rows ln the matrlx and hence display. with a large number of rows can be used increasing the Y resolution without .acrificing the contrast. Multiple waveforms with or without legends can be displayed. Typical applications are in' multitrace oscilloscopes and LOglC Analyzer •. This technique can also be adopted in application. wherein the number of selected. elements is a variable with an upper bound n (n «N), typical application being displays for video games.
2
Ref!,rences
1.
,Alt P.M. and Ples~ko P., 'Scanning Limitations of Liquid Crystal Displays', IEEE Trans ED, 1974, ED 21, ~p 14b-SS
2.
Hisao Hanmura, Takao Miyash1ta, 'Mult1trace Liquid eryst •.l Oscilloscope', JAPAN DISPLAY '83, Proceedings cf t~e 3rd International Display Research Conferenc~ 1983, pp 366-7.
3.
Shanks LA., "olland P.A., Hughes A.J., 'Liquid. Crystal Oscilloscope Displays' , SID Digest 1978, pp 98-99.
The selection ratio ~hieved in the present technique is [ Inl ( 1ri"-1)] 1 which is higher in comparison with the earlier technique of sequential frame multiplexing of waveforms proposed by Shanks et al for multitrace operation, (Ref. S) = [n/h-l) 1/2 (Table which gives a selection ratio
Shanks r. A. • and Holland P. A. , 'Addressing Methods for Non-'lUltiplexed Liquid Crystal Osci Iloscope Displays', SID Digest 1979, pp 112-113·
1).
5.
In Ref.2 a multitrace o.cillo.cope discussed has a 64 rows matrix LCD with 32 lines multiplexing. If a comparable mixture is used one can display 11 waveforms, using the present technique without any limitations on the matrix size. With L. C. mixtures currently available one can easily construct a display for 16 traces (N = 49 lines) using the proposed technique. eq
Ei ji Kaneko, 'Liquid Crystal Matrix Displays', Advances in Image Pickup and Display, Vol. 4, Edited by 8.Kazan, Academic Press, 1981,pp.38-43.
6.
J. and K,"etz A.R., 'Ultimate Limits Nehring for Matrix Addre'ising of RMS Responding Liquid Crystal Dlsplays', IEM Symposium on the Physics and. Chemistry of Liquid Crystal Devices, 1979, IEEE Trans ED, 1979.
7.
Clark M.G., Shanks LA., Patterson N.J., 'General Theory of Matrix Addressing Liquid Crystal Displays', SID Digest 1979, pp 110-111.
8.
Horiklri K., Ueda f., Ineno H., Aral H. and Tsuboi Y., 'Liquid Crystal Instrument Panel Using !lovel Display Driving Techniques', Third International Conference on Automotive Electronics'. 1 Mech.E.Conference Publications 1981 - 10, C162/81, pp.11-16.
Ackriowledl!ement The author is greatly indeoted to Prof. S.Chandrasekhar, Dr. N.V.Madhusudana and Prof. 8.S.Sonde for their guidance, va-luable discussions and encouragement. The author i. al.o thankful to K. Subramanya, S.A.Majeed and H.SubraconyaDl for the fabrication of the display.
SID 86 DIGEST • 131
