Iec ts 62715 5 2 2016

2 6.4.1 Colour gamut are variation by viewin an le.. 6.6 Half-luminan e an half -contrast viewin an le.. In ex e tional circ mstan es, a tec nical commit e may pro ose the publ cation of

IEC TS 6271 5- 5- 2

Edit io 1.0 2 16-0

Flex ible display dev ices –

Part 5- 2: Measuring met hods of opt ical charact eristics f om the vantage point

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IEC TS 6271 5- 5- 2

Edit io 1.0 2 16-0

Flex ible display dev ices –

Part 5- 2: Measuring methods of opt ical charact eristics f om t he v antage point

for curv ed display s

FOREWORD 4

1 Sco e 6

2 Normative ref eren es 6

3 Terms, def i ition an a breviation 6

3.1 Terms an def i ition 6

3.2 Ab reviation 8

4 Stan ard me s rin eq ipment 8

4.1 Vide sig al generator 8

4.2 Non-contact LMD 8

5 Stan ard me s rin con ition 9

5.1 Stan ard me s rin en ironmental con ition 9

5.2 Power s p ly 9

5.3 Warm-up time 9

5.4 Stan ard me s rin dark ro m con ition 9

5.5 Adju tment of display mod les 9

5.6 Me s rin ge metry for vantage p int 10 5.6.1 General 10 5.6.2 Me s rin ge metry in horizontal vantage p int 10 5.6.3 Me s rin ge metry in vertical vantage p int 10 5.7 Me s rin layout for viewin p sition 1

5.7.1 General 1

5.7.2 Me s rin layout by movin LMD 1

5.7.3 Me s rin layout by rotatin the display mod le 12 5.8 Minimum c rvature radiu f or the me s rement 13 5.9 Scre n vis al an le 14 5.9.1 Scre n vis al an le of a f lat display mod le 14 5.9.2 Scre n vis al an le of con ave typ display mod le 14 6 Me s rin method of o tical c aracteristic 15 6.1 General 15 6.1.1 Me s rin items 15 6.1.2 Me s rin p int location 15 6.1.3 Test p tern 16 6.2 Me s rin method 17 6.2.1 Me s rin method at the s re n centre p sition 17 6.2.2 Me s rin method at viewin an le p sition 18 6.3 Optical c aracteristic of white b x by viewin an le 18 6.3.1 Luminan e variation by viewin an le 18 6.3.2 Contrast ratio variation by viewin an le 19 6.3.3 Chromaticity variation by viewin an le 2

6.4 Optical c aracteristic of colour b x by viewin an le 2

6.4.1 Colour gamut are variation by viewin an le 2

6.4.2 Chromaticity variation an ΔE by viewin an le 21

6.5 Uniformity an u iformity variation 2

6.5.1 General 2

6.5.2 Luminan e u if ormity an u iformity variation by viewin an le 2

6.5.3 Chromaticity u if ormity an u iformity variation by viewin an le 2

6.6 Half-luminan e an half -contrast viewin an le 2

6.6.1 Half -luminan e viewin an le ran e 2

6.6.2 Half -contrast viewin an le ran e 2

7 Re ortin 2

7.1 Req irements of e ortin 2

7.2 Recommen ation of me s rement res lts re ortin 2

Biblogra h 3

Fig re 1 – Me s rin layout for non-contact me s rement 9

Fig re 2 – Me s rin ge metry in horizontal vantage p int ( o view) 10 Fig re 3 – Me s rin ge metry in vertical vantage p int (side view) 1

Fig re 4 – Me s rin ge metry by horizontal viewin an les ( o view) 12 Fig re 5 – Me s rin ge metry by horizontal display direction ( o view) 13 Fig re 6 – Minimum con ave typ c rvature radiu for the me s rement ( o view) 14 Fig re 7 – Scre n vis al an le of con ave typ display device ( o view) 15 Fig re 8 – 9-p int location for vantage-p int me s rement 16 Fig re 9 – Nine white b xes f or vantage-p int me s rement 16 Fig re 10 – Nine me s rin p ints for vantage-p int blac me s rement 17 Fig re 1 – Nine-colour b xes of R, G an B for vantage-p int me s rement 17 Fig re 12 – Me s rin direction of 9 vantage p ints 17 Fig re 13 – Me s rin direction (rig t side) by viewin an le 0 o , 15 o , 3 o an 4 o 18 Fig re 14 – Me s rin direction (rig t side) by viewin an le 0°, 15°, 3 ° an 4 ° (front up er view) 18 Fig re 15 – Me s rin method for half -luminan e viewin an le 2

Ta le 1 – Example of me s rement res lts f or the o tical c aracteristic 2

Ta le 2 – Calc lation res lts from the me s rement data of Ta le 1 2

INTERNATIONAL ELECTROTECHNICAL COMMISSION

FLEXIBLE DISPLAY DEVICES –

Part 5-2: Measuring methods of optical characteristics

f rom the vantage point for curved displays

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sp cif i ation when

• the req ired s p ort can ot b o tained for the publ cation of an International Stan ard,

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Tec nical sp cif i ation are s bject to review within thre ye rs of publ cation to decide

whether they can b tran f ormed into International Stan ard

IEC TS 6 715-5-2, whic is a tec nical sp cif i ation, has b en pre ared by IEC tec nical

commit e 1 0: Electronic display devices

The text of this stan ard is b sed on the fol owin doc ments:

En uiry draft Re ort o v tin

Ful information on the votin for the a proval of this tec nical sp cif i ation can b fou d in

the re ort on votin in icated in the a ove ta le

This publ cation has b en draf ted in ac ordan e with the ISO/IEC Directives, Part 2

A l st of al p rts in the IEC 6 715 series, publs ed u der the general title Flex ible dis lay

d evic s, can b fou d on the IEC we site

The commit e has decided that the contents of this publ cation wi remain u c an ed u ti

the sta i ty date in icated on the IEC we site u der "htp:/we store.iec.c " in the data

related to the sp cifi publ cation At this date, the publ cation wi b

• tran formed into an International stan ard,

• with rawn,

• re laced by a revised edition, or

IMPORTANT – The 'colour inside' logo on the cov r pa e of this publ c tion in ic te

th t it contains colours whic are considere to be us f ul f or the cor e t

und rsta ding of its conte ts Us rs s ould theref ore print this doc me t using a

colour printer

FLEXIBLE DISPLAY DEVICES –

Part 5-2: Measuring methods of optical characteristics

f rom the vantage point for curved displays

This p rt of IEC 6 715, whic is a tec nical sp cif i ation, sp cif ies the general rules an the

detais of o tical me s rin method f rom a fi ed p int ( he so-cal ed vantage p int for

c rved emis ive an tran mis ive typ display s c as OLED an LCD in dark ro m

con ition This doc ment foc ses on con ave s a e large s re n display (non-p rta le)

arou d a horizontal an /or vertical axis with fi ed or variable c rvature radiu

The me s rin method stipulated in this tec nical sp cifi ation is a pl ed to the c rved

display mod les u der the folowin states:

• vantage-p int luminan e variation by viewin an les

• vantage-p int contrast ratio variation by viewin an les

• vantage-p int c romaticity variation of white colour by viewin an les

• vantage-p int colour gamut are variation by viewin an les

• vantage-p int c romaticity variation of primary colours by viewin an les

• luminan e u if ormity an its u if ormity variation by viewin an les

• c romaticity u if ormity an its u iformity variation by viewin an les

• viewin an le of half-luminan e

• viewin an le of half -contrast

The f ol owin doc ments, in whole or in p rt, are normatively referen ed in this doc ment an

are in isp n a le for its a pl cation For dated ref eren es, only the edition cited a ples For

u dated ref eren es, the latest edition of the referen ed doc ment (in lu in an

amen ments) a pl es

IEC 6 715-1-1, Flex ible d is lay de ic s – P art 1-1: Termin lo y a d letter s mb ls

3 Terms, def initions and abbreviations

display that has a sin le c rvature radiu alon the s re n horizontal y an /or vertical y

Note 1 to e try: Th c rv ture ra iu of e c s re n p sitio is fix d b th ma ufa turer or u er c ntrola le

c rv ture ra iu

Note 2 to e try: Th dire tio of c rv ture mig t b c n a e or c n e fom th viewer’s p sitio

Note 3 to e try: Th c rv d s re n dis la is als c le c rv d dis la , a inc rv d TV a d c rv d mo itor.

3.1.2

v nta e-point me s reme t

test con g ration in whic me s rements are taken at variou me s rin p ints on the

display s re n throu h a common o servation p int in sp ce in front of the s re n

Note 1 to e try: Th o s rv r (at th viewin dista c D) is at a f i e p int, th s -c le v nta e p int or

viewin p int, a d th n fom th t f i e v nta e p int, th a gle of view fom th s re n c ntre to th c rn rs is

c a g d a c rdin to h ma viewin dire tio s toward th s re n

Note 2 to e try: In this d c me t, th v nta e p int for th me s reme t is lo ate o th s me h riz ntal pla e

a th dis la c ntre, a d o a ln b twe n th dis la c ntre a d th dis la ’s a is of otatio

Note 2 to e try: Th h riz ntal viewin a gle is th a gle b twe n th s re n n rmal dire tio a d th v nta e

p int, b th lyin o th s me h riz ntal pla e

Note 3 to e try: Th v rtic l viewin a gle is th a gle b twe n th s re n n rmal dire tio a d th v nta e

p int, b th lyin o th s me v rtic l pla e

3.1.5

lumina c v riation by viewing a gle

p rcent dif feren e of display white luminan e, b twe n normal in iden e (at 0° viewin an le)

an a sp cif i viewin an le at e c s re n me s rin p int or averaged over the s re n

me s rin p ints

3.1.6

contra t ratio v riation by viewing a gle

p rcent dif feren e of contrast ratio b twe n normal in iden e (at 0° viewin an le) an a

sp cif i viewin an le at e c s re n me s rin p int or averaged over the s re n me s rin

p ints

3.1.7

c romaticity v riation by viewing a gle

c romaticity dif f eren e b twe n normal in iden e (at 0° viewin an le) an a sp cif i viewin

an le at e c s re n me s rin p int or averaged over the s re n me s rin p ints

3.1.8

lumina c uniformity v riation by viewing a gle

p rcent dif feren e of display white luminan e u if ormity b twe n normal in iden e (at 0°

viewin an le) an a sp cifi viewin an le

3.1.9

c romaticity unif ormity v riation by viewing a gle

dif f eren e of c romaticity u iformity at normal in iden e (at 0° viewin an le) to the other

half -contra t viewing a gle

horizontal viewin an le that has the half value of the contrast at the normal direction

3.2 Abbre iations

For the purp ses of this doc ment, the fol owin a breviation a ply

CCT cor elated colour temp rature

CIE Commis ion Internationale de l Eclairage (International Commis ion on

An analog e vide sig al generator or a digital vide sig al generator is u ed The sig al

c aracteristic s al matc with the me s red c rved display mod le Input sig al, in this

doc ment, me n pre-gamma sig al an APL me n p st-gamma APL

4.2 Non-conta t LMD

For the purp se of vantage-p int me s rement, the non-contact LMD s al b u ed When

u in a non-contact LMD, a sp ctroradiometer or a non-contact colorimeter is in tal ed, as

s own in Fig re 1 The o tical axis of the non-contact LMD s ould b normal in the case of

me s rin the centre of the display s rf ace In this doc ment, for the purp se of vantag

e-p int me s rement, the me s rin distan e l

M

f rom the LMD to the centre of the display

s re n s al b either the desig viewin distan e or 3V where V is the ef fective s re n heig t

of the display an H is the horizontal y ef f ective s re n width of the display The desig

viewin distan e mig t b recommen ed b sed on the display resolution an c rvature radiu

The LMD colour me s rements s al comply with the colour matc in fun tion for the CIE

19 6 stan ard colorimetric o server

Figure 1 – Me s ring la out f or non-conta t me s reme t

5 Sta dard me suring conditions

5.1 Sta dard me s ring e vironme tal condition

Me s rements s al b car ied out u der the stan ard en ironmental con ition When

dif ferent en ironmental con ition are u ed, they s al b noted in the re ort

Atmospheric pres ure: 8 kPa to 10 kPa

5.2 Power s pply

The p wer s p ly for drivin the DUT s al b adju ted to the rated voltage ± % In ad ition,

the freq en y of the p wer s p ly s al provide the rated freq en y ± %

5.3 Warm-up time

Me s rements s al b started af ter the display mod les an me s rin in truments ac ieve

sta i ty Suf f icient warm-up time is def i ed as the time ela sed f rom when the s p ly source

is switc ed on, an a 10 % gray level of input sig al is a pled to the DUT, u ti re e ted

me s rements of the display s ow a variation in luminan e of no more than 2 % p r min te

an 5 % p r hour

5.4 Sta d rd me s ring dark ro m con itions

The luminan e contribution from the b c grou d i umination reflected of f the test display

s al b ≤ 0,01 c /m

2

If this con ition is not satis ed, then b c grou d s btraction is req ired

an it s al b noted in the ambient p rf orman e re ort In ad ition, if the sen itivity of the

LMD is inadeq ate to me s re at these low levels, then the lower l mit of the LMD s al b

noted in the ambient p rforman e re ort The clothes of the o server(s) an the wal of the

ro m s al b dark in order to avoid the ref lection of the l g t emited from the display b c

onto the display The me s rement f or al me s rin p ints of the display s re n an al

me s rin p sition s al proce d in the same dark ro m

5.5 Adju tme t of displa module

Luminan e, contrast an c romaticity of the white f ield an other relevant p rameters of the

display have to b adju ted to nominal statu in the detai sp cifi ation an they s al b

noted in the me s rement re ort When there is no level sp cif ied, the maximum contrast

an /or luminan e level s al b u ed These adju tments s al b held con tant f or al

me s rements, u les noted otherwise in the me s rement re ort Ad itional con ition are

sp cif ied se arately f or e c me s rin method

5.6 Me s rin geometry for v nta e point

To me s re in vantage-p int direction , the display mod le s ould b in tal ed on a rotata le

an ti ta le f i ture to ena le the c an es in horizontal, vertical, an /or o l q e me s rin

direction In 5.6, it is as umed that the display mod le s al b general y in tal ed in the

vertical p sition to the grou d The c rvature typ of the examples is con ave, but the con ex

typ is also avai a le for these a pl cation The me s rin direction that is the same as the

viewin direction is varied ac ordin to e c vantage p int an e c viewin an le of the

me s rin p sition

5.6.2 Me s rin geometry in horizontal v nta e point

Fig re 2 s ows the me s rin ge metry of the to view in the horizontal vantage p int The

me s rin distan e l

M

at the lef t or rig t me s rin p int of the s re n may b u eq al to

that of the s re n centre, whic wi req ire the LMD to b refoc sed at these p ints The

me s rin distan e is b sed on the stan ard viewin distan e of the normal direction It can

b me s red b twe n the s re n centre of the display mod le an the o tical len of the LMD

Figure 2 – Me s ring geometry in horizontal v nta e p int ( op view)

5.6.3 Me s rin geometry in v rtic l v nta e point

Fig re 3 s ows the me s rin ge metry of the to view in the vertical vantage p int The

me s rin distan e l

M

at the up er or lower me s rin p int of the s re n may b u eq al to

that of the s re n centre, whic wi req ire the LMD to b ref oc sed at these p ints When

u in a trip d mou t for the LMD, the LMD mig t b rotated by the mou t p int Becau e of

the ga l

D

b twe n the LMD len an the mou t p int, the viewin an le of the up er/lower

an lef t/rig t me s rin p int of the s re n b comes sl g tly smal , but if l

D

< 0,1 l

M, it can b

Figure 3 – Me s ring g ometry in v rtic l v nta e point (sid view)

5.7 Me s rin la out f or viewing position

When watc in a display, ac ordin to the viewin p sition, a viewin an le s al b set up

b twe n the display’s p rp n ic lar direction an the viewin direction In 5.7, f or the

me s rement by the viewin an le with the actual watc in con ition of c stomers, the

ran e of the viewin p sition of normal to ± 5° of the display whic is p s ible in the actual

u age s al b a pl ed The ran e of the viewin an le mig t b determined from over 9 %

of actual u ages of con umers when watc in large s re n display

For the me s rement in the viewin an le, as the viewin an le is mainly c an ed in the

horizontal direction, the LMD can b in tal ed on a mova le trip d arou d the display to

ena le to c an e the horizontal viewin an le Alternatively, the display mod le may rotate

horizontal y to c an e the viewin an le when the LMD is f i ed De en in on the display

size or the me s rement ro m sp ce, one of the alternatives s al b ado ted

5.7.2 Me s rin la out by moving LMD

The viewin direction of the viewer b comes the viewin an le of the display In this case, the

me s rement distan e s al not c an e regardles of the viewin an les The me s rin

ge metry of 0° to 4 ° is s own in the f i ure As the actual watc in con ition , the viewin

an le wi b recommen ed to b 0°, 15°, 3 ° an 4 ° in Fig re 4 In this case, the o p site

sides of the viewin an les do not have to b me s red b cau e general y most of the c rved

display are almost s mmetrical horizontaly in the o tical variation b twe n the lef t side an

rig t side viewin an les Fig re 4 s ows the me s rin ge metry of the to view by

horizontal viewin an les from 0° to 4 ° of the rig t side

IEC

LMD Curv d dis la mo ule

Figure 4 – Me s ring geometry by horizontal viewing a gle ( op view)

In e c viewin an le of the viewin p sition, the me s rin direction is c an ed by the

viewin an le at the same time Fig re 4 s ows the me s rin direction of the s re n centre

by the horizontal viewin an le (Ɵ

H) that is cau ed by the viewer’s p sition In an me s rin

p sition, the me s rement distan e l

M

s ould not b c an ed But b cau e of the an le of

the vantage p int, the viewin an les an the me s rin distan es of the other p ints of the

s re n are dif f erent from those of s re n centre

5.7.3 Me s ring la out by rotating the displa mod le

In te d of movin the LMD, the display mod le itself can b rotated The display mod le

s ould b in tal ed on a rotata le f i ture to ena le c an es in the horizontal viewin an le

b sed on the display s re n centre Fig re 5 s ows the me s rin ge metry of the to view

by the horizontal display direction from 0° to 4 °

H

= 15° (viewin a gle)

Figure 5 – Me s ring geometry by horizontal displa dire tions ( o view)

As in 5.7.2, b cau e of the an le of the vantage p int, the viewin an les an the me s rin

distan es of the other p ints of the s re n are dif f erent from those of the s re n centre

5.8 Minimum c rv ture ra ius for th me s reme t

When the maximum viewin an le is 4 ° in this me s rement, the c rvature radiu of the

con ave typ display mod le s ould b big er than 3 V/9 f or 16:9 asp ct ratio display as

Fig re 6 s ows Asp ct ratio me n the horizontal len th vers s the vertical len th of the

s re n In case of a smaler c rvature radiu than the minimum c rvature radiu , it wi not b

p s ible to me s re the s re n ed e of the viewer’s side or there wi b an inac urate

me s rement at 4 ° an le of viewin distan e 3V Fig re 6 s ows the minimum c rvature

radiu of a con ave typ c rved display device in the to view In Fig re 6, if the c rved

Figure 6 – Minimum con a e type c rv ture

ra ius f or th me s reme t ( op view)

5.9 Scre n vis al a gle

5.9.1 Scre n vis al a gle of a f lat displa module

When a complete f lat display of a 16:9 asp ct ratio display a horizontal/vertical ratio k whic

is 1,7 8, for example, the s re n vis al an le at a 3V viewin distan e is as f ol ows:

16

2t an

32

V

Vk

5.9.2 Scre n vis al a gle of conc v type displa mod le

In case a con ave typ c rved display of 16:9 asp ct ratio display a horizontal / vertical ratio

k whic is 1,6 , when the c rvature radiu is 3V, the horizontal s re n vis al an le at a 3V

viewin distan e that is the an le from the viewer to the lef t en an rig t en of the s re n is

c

16

39

16

322

ππ

Θ

(2)

(3)

Fig re 7 s ows the s re n vis al an le of a con ave typ display device in the to view

Figure 7 – Scre n vis al a gle of con a e type displa d vic ( o view)

6 Measuring methods of optic l c aracteristics

6.1.1 Me s rin items

The me s rin items for c rved display c aracteristic are as f ol ows:

• luminan e variation of white b x by viewin an les

• contrast ratio variation of white b x by viewin an les

• c romaticity variation of white b x by viewin an les

• colour gamut are variation by viewin an les

• c romaticity variation of colour b x by viewin an les

• luminan e u if ormity an u iformity variation by viewin an les

• c romaticity u if ormity an u iformity variation by viewin an les

• viewin an le of half-luminan e

• viewin an le of half-contrast

6.1.2 Me s rin point loc tions

For the vantage-p int me s rement, the n mb r of me s rement p ints is general y 9 The

location of the 9 p ints are s own in Fig re 8 The test p tern s al b sp cif ied de en in

on the me s rin items, but the me s rin p sition is alway the same