`~~2, Patent Application Publication ~io> Pub. ~vo.: US 2006/0103913 Al
`May 18, 2006
`Handschy et al.
`~~~~ Pub. Date:
`
`US 2006Q103913A1
`
`(54) OPTICS ARRINGEMENTS INCLUDLVG
`LIGHT' SOURCE ARRANGEMENTS FOR Av
`ACTIVE MATRIX LIQUID CRYSTAL ItVIAGE
`GENERATOR
`
`X76) Inventors: Mark A. Handschy. Botilder, CU (US):
`D'Iichael R. Meadows, Nederland, CO
`(US); Holden Chase, Lafayette, CO
`(US)
`
`Correspondence Address:
`NL~RSH, FISCHMAVN & BREYFOGLE LLP
`3151 SOUTH V.AUGFIN WAY
`SUITE 411
`AURORA, CO 80014 (US)
`
`(21) Appl. No.:
`
`11/317,936
`
`(22) Filed:
`
`Dec. 23, 2005
`
`Related U.S. Application Data
`
`(C,0) Continuation of application Nn. 10/067,516, filed on
`Feb. 4, 2002, now Pat. No. 7Al2,730, which is a
`continuation of application No. 09/735,109, fled on
`Dec. 13, 2000, now Pat. No. 6,359,723, wluch is a
`continuation of application No. 09/422,815, filed on
`Oct. 21, 1999, now Pat. No. 6,195,136, which is a
`continuation of application No. 09/046,3)8, filed on
`Mar. 24, 1998, now Pat. No. 6,038,005, which is a
`division of application No. 03!362,234, filed on Dec.
`22, 1994, now Pat. No. 5,808,800.
`
`Publication Classification
`
`(51) Int Cl.
`cnzx 2~ino
`~aoo~.oi~
`(52) U.S. CI . .............................................................. 359/290
`(57)
`ABSTR:ICT
`A system for producuig modulated light is disclosed. The
`system comprises a spatial light modulator includiug a light
`modulating medium switchable between different states so
`as to act on light iu ways which term overall patterns of
`modulated light. Tlie system also includes an arrangement
`for switching the modulating medium between die di$erent
`states in a controlled way and an illumination arean~emcnt
`for produciu; a source of light. The system further includes
`au optics arrangement for directing light from the source of
`light into the spatial light modulator and for directing light
`from the spatial light modulator through a predetermined
`source imaging area. The optics arrangement cooperates
`with the illunvnation arrangement and the spatial light
`modulator so as to produce a real image of the source of light
`within the source imaging area such that au individual is able
`to view a virn~al unage of the overall patterns of modulated
`light from flee source ima~iug area. A variety of novel optics
`arrangements are disclosed including specific combinations
`of different light sources, diffusing plates, polarizers, beam
`splitters, analyzers, lenses, mirrors, and holographic optical
`elements which allow the overall optical arran,ement to be
`miniaturized to the same degree and iu coordination with the
`spatial light modulator. The different light sources uiclude
`using a plurality o1~ li~h[ sources, such as LEDs, to form an
`array of light sources, each of the light sources providing
`light to a corresponding portion of the spatial light modu-
`lator.
`
`32
``~—
`34
`.
`
`30
`
`26
`
`,.
`/.^~
`~~
`
`----
`
`~..~~
`
`~~.
`
`•~
`36 38 ,• .~~.
`~
`•
`
`,.
`
`40
`
`~— F2--~---~
`
`Acuity v. Lynk
`Acuity Ex.1020
`
`IPR PAGE 1
`
`
`
`Patent Application Publication May 18, 2006 Sheet 1 of 10
`
`US 2006/0103913 AI
`
`~
`
`24
`
`~,'~
`
`.. __
`.._1_.
`•
`
`~~.
`
`'•.~.~
`
`14
`
`18•
`'. ' 20
`t
`.'
`
`,.
`
`,.
`
`~r
`
`~.
`,•.'
`,~
`.~ '.
`►.
`
`•~
`
`~.,.
`
`•'
`
`,-
`
`~
`
`•.
`
`F 1---------~
`
`"•~
`
`~.
`~ `. ,
`
``.~
`
`~.~
`•.~
`
`Ff9U1'21 {PriorArt)
`
`32
`
`3~
`
`~
`
`--
`--
`
`---
`
`/ 26
`
`yf
`
`---
`
`-- _,~
`
`40
`
`-------- F2--=--~~i
`Figure 2A
`
`,.
`
`.~
`.~ •.
```.~
`.' .•
`3U JV ~~ ~ ~~~~♦
`.
`,
`.- .•
`.,
`•~
`42
`.'
`
`IPR PAGE 2
`
`..•
`..
`.•
`.•
`.•r•,.,
`.•.•.•.`
`
`.`
`
`12
`
`8
`
`
`
`Patent Application Publication May 18, 2006 Sheet 2 of 10
`
`US 2006/0103913 Al
`
`Figure 2B
`
`R
`1
`
`49
`34 F ~ -
`
`• --
`
`~g
`
`....
`.'.'
`. ~.'
`.~.
`,~
``:.
``: .
``: .
`..
`
`. ..:~;~
`~ v
`42
`..•
`.. .• t
`•
`38
`. .
`. ,•.,.,
`..
`..
`.,
`•
`•
`
`~44
`
`36
`
`~,
`~.
`
`~
`~ ~
`~~
`~~
`~~
`~~
`~,
`~~
`~~
`~.
`~~
`~.
`
`~~
`~~
`" 4B
`~,
`~~
`
`~ .
`
`-------------~
`
`as
`
`56""'~
`
`~- D2~ Q2~
`~; .
`/~ R~ ~\
`¤
`¤
`i ~
`.. ..
`• • •• ~
`54
`54 ; `~ '. ~ 5d
`,~ •~ .~. .
`.
`••
`".
`.
``• .
`•
`r,
`
`~~~
`~~~
`..~
`
`~,~
`~~~
`~.~
`~;
`•,,~
`~; ~ ~- 48
`~~~
`~~~
`~,~
`~,
`~;
`~,~,
`~; ~
`~,
`~,~
`
`X46
`
`--------------t,~
`
`IPR PAGE 3
`
`
`
`Patent Application Publication May 18, 2006 Sheet 3 of 10
`
`US 2006/0103913 Al
`
`~.. .~.. .~.
`
`~
`~
`
`•~~ 62
`•' ~.
`~ • ~ ' • , /---58
`~ ~ • s
`c
`.+ ~
`~
`..
`,.
`,. .~
`.,
`
`36
`
`~
`
`48
`
`~
`
`,
`
`~
`
`~
`
`60
`
`~
`
`~
`
`1 1
`
`52~ •'
`
`Figure 4
`
`~~
`
`52
`
`~
`
`.~
`
`~~
`
`i~
`
`~
`
`~
`~
`y
`
`
`
`t ----
`~
`~
`~
`~
`i
`
`.i---r ---
`~i ' ~
`~
`~
`E
`~
`~
`~
`
`.•
`
`•.
`.~
`
`28
`
`~
`
`34
`
`'•.~..
`
`,.~,
`•
`'
`-------------------------- '~
`
`36
`
`.,~
`.,.•
`
`38
`
`Figure 5A
`
`_. ._
`
`c,
`C ~ -
`52
`
`_.. _
`
`-..
`
`--
`
`Figure 5B
`
`•..
`
`.-
`
`,.
`••
`'+
`
`•~
`
`62
`
`IPR PAGE 4
`
`
`
`Patent Application Publication May 18, 2006 Sheet 4 of 10
`
`US 2006/0103913 Al
`
`~'~~_~62
`
`• ~~.
`~ .
`•
`•' ~5B
`
`,.
`,.
`
`' ~
`
`36
`
`48
`
`, ~
`
`~
`
`~
`
`~ ~
`"
`~
`~~ '
`~~
`ti
`~
`
`""~
`
`~
`
`~,,,.
`
`~,
`~,
`~'
`~'
`~'
`''
``
`-~-
`
`=~-=-'rti
`y
`~
`~
`~
`
`1
`
`M
`
`601
`
`52~
`
`LL:~t,
`
`52~ ,
`.`
`
`Figure 6
`
`"._~.__`_9._~.
`
`64 --~
`
`72
`
`Figure 7A
`
`.,~
`
`Figure 7B
`
`IPR PAGE 5
`
`
`
`Patent Application Publication May 18, 2006 Sheet 5 of 10
`
`US 2006/0103913 Al
`
`~~ 38
`
`•••
`
`• ~88
`•
`
`36
`
`~
`
`• ~
`
`~
`
`•
`
`~
`
`'~ 38
`
`• ~88
`
`~•_ r-36
`
`~
`
`90
`
`8
`.'
`.'
`.'
`
`.~
`.~
`.~
`
`.~
`
`Figure 9
`
`.. _,.
`,.—.-_, ,
`
`I~--------------~
`
`IPR PAGE 6
`
`
`
`Patent Application Publication May 18, 2006 Sheet 6 of 10
`
`US 2006/0103913 Al
`
`~94
`
`36
`
`~~~'\
`
`~. 38
`
`•••
`
`•••••
`
`' 100
`
`•
`
`e
`
`Figure 10
`
`.~.~
`,~
`.' !
`
`4a
`
`ss
`
`.
`'
`
`•`~"~
`~. 38
`
`••
`
`•
`
`~ ~94
`•
`
`36
`
`•••
`
`
`
`~
`
`~
`,02 ;
`
`~
`
`if
`
`
`
`,~,~.,
`.,
`
`Figure 11
`
`~
`
`M~ • ~
`• ~
`• ' I ~
`
`1
`[ ~ . ~ ~
`~
`
`~
`
`28--~
`.-''~~+~r
`i
`
`46
`
`IPR PAGE 7
`
`
`
`Patent Application Publication May 18, 2006 Sheet 7 of 10
`
`US 2006/0103913 Al
`
`•"~_'~
`,' ~. 38
`
`•••
`
`• ' 104
`•
`
`•
`
`36
`
`' 140
`
`Figure 12
`
`r
`.i
`.~
`. ~
`
`106
`
`;
`~
`~
`~
`
`28
`
`~~ 38
`
`~
`
`~.
`
`""' ~•
`
`108
`
`36
`
`1~0
`
`'f'~~! T
`
`98
`
`~~
`
`~
`
`, 110
`'
`112—'~~ ,-------•----•--•
`
`46
`
`Figure 13
`
`IPR PAGE 8
`
`
`
`Patent Application Publication May 18, 2006 Sheet 8 of 10
`
`US 2006/0103913 Al
`
`.~~\
`,' ~. 128
`
`r~
`128
`
`114
`
`~
`
`i
`i
`~;~ I36
`
`116
`
`r
`
`118—~7
`
`r~. ~
`~
`~ •
`y
`
`.,
`
`~
`
`~
`t ~
`
`• ,
`~
`
`•a ,
`•
`~~
`~~ :124 ~
`~
`~
`~ ,~
`` ~ . ~ ~
`,
`~
`~
`~, ,,
`,, ,~
`~ { I
`~ 1
`:►
`''
`46 ~' 120• 126 ~:~~ ►
`I y'
`►
`~~
`
`
`~ 4 ~ •1.:
`t
`
`1
`1 ~
`
`~`~
`. ~
`~
`
`~
`
`122 :•
`~
`
`,f
`' ~ `,
`~;
`120 ~•~
`+ ~ a.s
`u
`I
`,' ,
`~
`r
`~t
`
`f
`
`11~
`
`.~
`
`124
`
`116
`
`118—
`
`.~
`
`Figure 14A
`
`Figure 14B
`
`~~r —~ 12$
`.~ . .a
`~~ . ..~
`•~ ~ ~~•
`s •`~
`•~ ~
`. , . , • .
`13~~: ; i
`~ ~ ~~
`• •
`~
`~ f
`1
`~ f
`~
`1
`r
`r
`
`1 ; ~
`•
`1
`f
`
`~
`~ ,
`t
`~
`
`~
`
`:~~ 128
`
`~
`
`~'
`
`•
`•
`
`~ ~ 130
`
`•
`
`~
`
`•
`•
`
`~2A
`
`36
`
`36
`
`•
`
`~
`~
`n ~,_
`r~~. ~
`124 '
`,s—= ~ _
`
`~
`
`~
`
`116
`~
`~
`~
`
`~i ~ ~i ~ ~i i ~
`~ ¤
`a ~ ~ • ~
`~•
`~ ~ ♦~~
`~
`~~ ~
`
`i 118
`
`~
`
`~~ 116 ~ ~~ \118 'r
`
`i
`~
`~ •
`~
`~
`•
`~
`~
`~
`~
`t
`~
`~
`~
`~
`t
`•
`~
`~
`~
`+
`~
`w
`~
`•
`~
`~
`~
`t
`~
`~
`~
`l
`~
`1
`~ ~
`+
`~ l
`
`~'
`
`46
`
`rN
`
`Figure 15A
`
`Figure 15B
`
`p ~
`i
`~ ~
`~ ~
`a ~
`~
`eta ~~
`s
`~ ¤
`~ ~ ~ ~ i~ ' s
`a
`1 /
`
`~
`
`1 ¤
`~, ~~
`~,
`} ~'
`
`/ 1
`
`Y
`
`M
`
`IPR PAGE 9
`
`
`
`Patent Application Publication May 18, 2006 Sheet 9 of 10
`
`US 2006/0103913 Al
`
`132 ~
`
`36
`
`,,
`
`Figure 16
`
`~ sa —~-~
`
`34
`
`~ 4 ~
`
`,~,~._
`' ,
`; 148 ' ~
`
`~
`
`2$
`---- -- ---
`~
`~
`~
`~.
`+
`;
`•'
`~
`' ~
`
`~
`i '
`~ ' ~
`~
`
`ss
`
`446
`
`---- '-
`
`Figure 17
`
`IPR PAGE 10
`
`
`
`Patent Application Publication May 18, 2006 Sheet 10 of 10
`
`US 2006/0103913 AI
`
`,-~
`~. `162
`~
`
`f
`
`Figure 18A
`
`;'
`
`•,
`
`~
`
`,~ ~~~~
`
`36
`
`/160
`l
`
`~~ ..
`~~..'
`
`~
`
`'
`
`,•
`152
`\ ~ .~-- 156
`
`/ `.
`
`154
`
`~'.~
`
`~`.
`
`166
`
`164
`
`152
`
`166
`164
`
`168
`Figure 1 SB
`
`~ ~
`
`Figure 18C
`
`154
`
`152
`
`d
`
`~' L
`
`A
`
`~5s
`
`17° ass
`
`',~~>:
`
`D4
`
`L ~ ` `.
`
`~~ `
`
`168
`
`_~J___
`
`/ 1` 1~ .a
`
`178
`Figure 19
`
`IPR PAGE 11
`
`
`
`US 2006/0103913 Al
`
`May 18, 2006
`
`OPTICS ARR~NGF,MF.vTS [NCI,UDING LIGHT
`SOURCE ARRANGEMENTS FOR AN ACTIVE
`~I~TRLX LIQUID CRYST.~L IVI:~GE GENERATOR
`
`GOVF,RNMF,NT CONTRACT CI:AiJSF
`
`[0001 This invention was made with Government support
`under contracts NAS9-13358 and NAS9-19102 awarded by
`the National Aeronautics and Space Administraliou and
`contracts D.A.A-HO1-92-C-R275 and D.AA-HO1-94-C-R154
`awarded by the .advanced Research Projects Agency. The
`Cioverrunent has certain rights in this invention.
`
`BACKGROUND OF THE IM~'ENTION
`
`[0002] The present invention relates generally to image
`generating systems, and more particularly to optics arrange-
`inents and light source arrangements especially suitable for
`miniahuized image aener~ting systems such 1s the minia-
`hirized image generator disclosed in U.S. Pat. No. 5,748,164
`entitled ACTIVE iVLATRIX LIQUID CRYSTAL IMAGE
`GENERATOR, which is incorporated herein by reference.
`
`[0003] One of the ongoing challenges facing the maini-
`facttire of ininiahire image Qeneratin~ systems is providing
`smaller and smaller systems. Miniahire image generatinn
`systems which are small enough to be mounted onto a
`helmet or small enough to be supported by a pair of
`eyeglasses will find a wide variety of uses if they can
`provide adequate resolution and hri~hmess in a small, low-
`power package at a low cost. Conventional technologies
`such as CRTs are difficult to minianirize and therefore do not
`hold much promise in tivs field. Alternatively, new systems
`based on VLSI integrated circuits are currently beiu~ devel-
`oped which provide much smaller spaliai light modulators
`for use in a miivatiu~ized image generating systems. How-
`ever, one of the problems in this field is providing optics and
`illuminating v-raugements which may be scaled down in
`coordination with the uiiniahirized spatial light modulator in
`order to provide an overall linage ~eneratin~ system which
`is practical and compact enough to be mounted onto a
`helmet or supported by a pair of glasses. <A~iother problem in
`this field is providing an illwuinating arrangement which
`requires as little power as possible in order to make the
`overall system more portable.
`
`[0004] Referring to FIG. 1, a prior art minianire image
`generator system generally designated by reference numeral
`10 will be described. System lU includes a transmissive
`spatial light modulator 12 which modLilates light from a light
`source 14 positioned itninediately adjacent to spatial light
`modulator 12 by selectively changing the polarization of
`light passim throuDh the spatial light modulator.:4 polarizes
`16 is positioned between light source 14 and spatial li=ht
`modulator 12 which allows light of one polarization from
`li;ht source 14 to enter spatial light modulator 12. !1n
`analyzer 18 is positioned adjacent to the opposite side of
`spatial light 12 ~~hich allows light of a particular polari~a-
`tion to pass through analyier 18. .An eyepiece lens 20 hiving
`a focal length Fl is positioned approximately one focal
`length Fl from spatial limit modulator 12 such that a viewer
`may see a vimial linage of the pattern of modulated light
`formed by spatial light modulator 12 when the viewer's eye
`is positioned iu an appropriate location. As shown in FIG.
`1, this arrangement results in a viewing region indicated by
`reference numeral 22 from which a viewer may view the
`
`entire virtual image of the pattern of modulated light pro-
`duced by the spatial lig(it modulator display.
`
`[0005] Iu the above described arrangement, since light
`source ld is positioned adjacent to spatial light tnodulator
`12, light source l4 must hlvc a light emitting surface with
`essentially the same surface area as spatial light modulator
`12. Also, in order For the optics to perform properly, the light
`source is a dithise light source. However, these requiretuents
`causes two major problems. First, a ]arae diffiise light source
`as described above is substatttiaily more expensive than
`other types of light sources. Second, because light source 14
`is diffuse, a large percentage of the light aeuerated by light
`source 14, indicated by lines 24, is directed to areas which
`are not within viewing regio~l 22 including areas in which
`the light does not pass fluou~h eyepiece lens 20. This wastes
`a la ae percentage of the light produced by light source 14
`and requires much more light to be produced than would be
`neces5lry if substantially all of the available light were
`directed into viewing region 22. This wastage of light
`significantly increases the power requirements of the overall
`system. As will b~ seen hereinafter, the present invention
`provides a variety of novel optics arrangements including
`novel light source arrangements which, when combined
`with miniahirized spatial light modulators, are capable of
`providing low power, compact miivaturized iinaoe generat-
`ing systems that may be used to produce a direct view
`miniature display.
`
`SUMMARY OF THE INVENTION
`
`[0006] As will be described in more detail hereinafter, a
`system for producing modulated light is disclosed. The
`system comprises a spatial light modulator including a light
`modulating medium switchable between different states so
`as to act on light in ways which form overall patterns of
`modulated light. T(ie system also includes means for switch-
`in~, the modulating medium between the di$erent states in a
`controlled way and illumination means for producing a
`source of light. 'fhe system fiirther includes optics means for
`directing light from the source of light into the spatial light
`modulator and for directing light fmm the spatial light
`modulator through a predetermined source imaging area.
`The optics means cooperates with the ilhimination means
`and die spatial light modulator so as to produce a real image
`of the source of light witivn the source ima~in~ area such
`that an individual is able to view a virtual image of the
`overall patterns of modulated light from the source imaging
`area.
`
`[0007] In one preferred embodiment of the present inven-
`tion the spatial light modulator is a refl~~c;tive type spatial
`light modulator and the optics means cooperate with said
`illumination means and said spatial light modulator such that
`some of the light passing from the illumination means to the
`spatial light modtilaYor overlaps with some of the light
`passim from the spatial light modulator to the source
`ima~in~ area.
`
`[0008] Iu another embodimenC of the present invention,
`die light source is provided by means of an array of linht
`emittinD sotvces such as LEDs (light emitting diodes)
`spaced apart by a predetermined distance. These spaced
`apart ]i~ht sources, in combination with the optical coulpo-
`ncnts, produce au equal plurality of images at the soi~rcc
`ltllagllla area which are spaced apart from one another by a
`
`IPR PAGE 12
`
`
`
`US 2006%0103913 A 1
`
`2
`
`May 18, 2006
`
`predetermined distance. The optical components of this
`embodiment may include a single collimating lens disposed
`optically between the light sources and the spatial light
`modulator, or alternatively, cnay include a plurality of col-
`limatin~ lenses, each of which is disposed optically between
`~u associated nne of the light sources and the spatial light
`modtilator so as to direct li=ht from its associated light
`source to a corresponding portion of the spatial light modu-
`lator.
`
`[0009] In the case of a plurality of collimating lenses, the
`optical components also include a single eyepiece lens
`which is disposed optically between the spatial light modu-
`lator and the sotu-ce imaging area and which dePmes a much
`greater focal length dean the focal length of each of die
`individual collimating lenses. Also, the light sources cagy be
`disposed optically approximately a focal length away troin
`flieir associated collimating lens, such that the plurality of
`imflges produced at flee source imaging area are substantially
`larger than their respective light sot~rces..Alternatively, in
`this arrangement, the light sources are disposed optically
`sli;htly closer to their associated collimating lens than one
`focal length so as to cause each collimating lens to direct
`light from its associated light source to the spatial light
`modulator in a slightly diverging iu~uiuer. The spatial rela-
`tionship between the limit sources and the divergence of the
`light from the collimating lenses are such that the plurality
`of iuia~es produced at die source imaain~ area overlap one
`another in a predeteniuned way.
`[0010] The plurality of light sources may be provided in a
`variety of arrangements. In a first arrangement, the arrange-
`ment includes a single dielectric substrate having on one
`surlice a pattern of electrically conductive leads adapted for
`connection to a source of electric power. A plurality of LEDs
`are individually attached to the substrate and electrically
`connected with the pattern of leads. An eyua] plurality of
`individual collimating lenses are attached to the substrate
`and disposed optically over associated ones of the I,F,Ds. In
`a second arrangement, the arringement includes a single
`LED wafer having ou one surface a pattern of electricllly
`conductive leads adapted for connection to a source of
`electric power. The pattern of leads divides the wafer into the
`plurality of LEDs. An ec~ua] plurality of individual collimal-
`ing lenses may be attached to the wafer and disposed
`optically over associated ones of the LEDs. Alternatively,
`the arrangement includes a single substrate which is attadied
`to the LEll wafer and which is integrally funned to define
`an associated colliinatina lens for each of the LEDs. In a
`third arrangement which may be any combination of the first
`end second ~u-rangcme:nt, the plurality of LEDs include
`LEDs of different colors thereby providing a color version of
`the miivaturized assembly.
`[0011] In a color version of the present invention, the light
`sources include different color licit sources, such as LEDs,
`which are spaced apart a predetermined distance d and
`which emit light outwardly at a maximum angle A. A light
`dif~iising plate is spaced from the light sources a distance L.
`Tlms, the positional relationship between the li;ht sources
`and the di$using plate is such that L is at least approximately
`equal to d/A. In this way, as will he seen, it is possible to
`obtain proper registration of Qie different color images even
`though the light sources are spaced apart from one another.
`[0012] As will be described in more detlii hereinafter, a
`variety of specific arrangements for the optical components
`
`of the system for producing modulated ]iglu are also dis-
`closed. These arrangements inchide specific combinations of
`a variety of IiL,ht sources, polarizers, beam sputters, lnalyz-
`ers, lenses, mirrors, and holographic optical elements
`arranged w direct the light from the light source into the
`spatial light modulator and from the spatial light modulator
`to the source imaging area.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`[0013] 11ie features of die present invention may best be
`understood by reference to die following description of the
`presently preferred embodiments together with the accom-
`panyinj drawings in which:
`
`[0014] FIG. 1 is a diagrammatic side view of a prior art
`miniaturized image generating system;
`
`[0015] FIG. 2A is a diagrauunatic side view of a miuiariire
`image generating system designed in accordance with the
`present invention having a light source positioned away
`from the spatial light modulator and including optical ele-
`ments w$ich Pi~nn a real image of the light source at a source
`imaging area and allow a viewer W view a virtual image of
`a pattern of modulated light funned by a spatial light
`modulator when the pupil of the viewer's eye is positioned
`in the source imaging area:
`
`[0016] FIG. 2S is a dia;rammatic side view of a basic
`reflective type miniahirized iina~e generating system
`designed in accordance with the present invention wlvch
`illustrates all of the elements of a particular optical system
`for the miniahvized image generltor including a light
`source, a spatial light modulator, vi eyepiece, a source
`imaging area, Ind a polarizing beam splitting cube for
`directing one polarization of li;ht from the light source into
`the spatial light modulator and fir directing the opposite
`polarization of light from the spatial light modulator to the
`eyepiece which directs the light to the som-ce imaging area
`forming a real image of the light source within the source
`imaLing area;
`
`[0017] FIG. 3 is a diagranunatic side view of one embodi-
`ment of a miniariirized image generating system designed in
`accordance with the present invention including a plurality
`of light sources which. in combination with the other optics
`components, produce a corresponding real image of the
`plurality of light sources at the source imaging area;
`
`[OOiS] FIG. 4 is ~ dia~r~urunatic side view of second
`embodiment of a miniaturized image generating system
`designed in accordance with the present invention including
`a plurality of light sources and a plurality of collimating
`lenses each of which is associated with a corresponding light
`source, which, in combination with the other optics com-
`ponents, produce a corresponding real image of the plurality
`of li~,ht sources at the source imaging area;
`
`[0019] FIGS. 5 ~ and SB are diagranunatic side views
`illustrating the optical relationship between the collimatinn
`lenses and the eyepiece lenses of FIG. 2 and FIG. 4;
`[0020] FIG. 6 is a diagrurunatic side view of the image
`generator of TIC:. 4 iu w$ich the light sources are positioned
`slightly closer to their associated collimatiu; lens than one
`focal length so as to cause each collimating lens to direct
`light from its associated light source to the spatial light
`modulator in a slightly diver~in~, manner;
`
`IPR PAGE 13
`
`
`
`US 2006%0103913 Al
`
`May 18, 2006
`
`3
`
`[002]] FiCS. 7A and 7R are diagrammatic perspective
`views of light source arrangements designed in accordance
`with the present invention for use in, for instance, the
`miivature image generator of FIG. a;
`
`[0022] FIG. R is a diagrammatic side view of a third
`embodiment of a miniaturized image ~eneratina system
`designed in accordance with the present invention including
`an auxiliary polarizer positioned optically beriveen the light
`source and the spatial light modulator;
`
`[0023] FIG. 9 is a diagrammatic side view of the minil-
`h~rized image generating system of FIG. 8 including an
`auxiliary analyzer positioned optically between the spatial
`li~lit modulator and the source imaging area;
`
`[0024] FIG. 10 is a diagrtuiunatic side view of a fourth
`embodiment of a miniattirized linage generating system
`designed in accordance with the present invention including
`an polarizes positioned optically between the light source
`and the spacial light modulator, au analyzer positioned
`between Qie spatial light modulator and the source imaging
`area, and a curved surface arrannement for directinn the light
`from the light source to the spatial light iuodulator and
`transmitting the light front die spatial light modtilator to the
`eyepiece which directs the light to the source imaging area;
`
`[0025] FIG. 11 is a diagrauuuatic side view of the min-
`iatm-ized image ~eneratina system illustrated in FIG. lU in
`which the polarizes and analyzer are formed as part of the
`curved surface arrangement;
`
`[0026] FIG. 12 is a dia~-airunatic side view of a fifth
`embodiment of a miniaturized image =enerating system
`designed in accordance wifli die present invention includinD
`a holographic polarizing beam splitter positioned optically
`between the light source and the spltial light modulator and
`between the spatial light modiilator and the source stagging
`area;
`
`[0027] FIG. 13 is a diagranunatic side view of a sixth
`embodiment of a miniahirized image generating system
`designed in accordance with the present invention including
`an edge-illuminated holographic illuminator;
`
`[0028] FIGS. 14A and 14B are diagrammatic side views
`of a seventh embodiment of a miivaturized image generating
`system desi;ned in accordance with the present invention in
`which the spatial light modulator is directly illuminated by
`the light source without other optics coinponeuts for direct-
`ing the light into the spatial light modulator;
`
`[0029] FIGS. 15A and 15B are diagranunatic side views
`of an eighth embodiment of a uiiniahirized iina~;e ~;eneratin~;
`system designed in accordance with the present invention in
`which the spatial light modulator is directly illuminated by
`the light source without other optics components for direct-
`ing the light into the spatial light modulator and the lig(it
`source is positioned between the spatial light modulator and
`tllc eyepiece lens;
`
`[0030] I'IG. 16 is a diagranunatic side view of a ninth
`embodiment of a miniahirizzd image =enerating system
`designed in accordance with the present invention including
`an arrangement for converting light which is not directed
`into the spatial light modulator by the polarizing beam
`splitting cube to the oppvsitc polarization and redirecting it
`back into the polarizing be~un splitting cube;
`
`[0031] FiG. 17 is a diagrannuatic side view of a tenth
`embodiment of a micvaturized image genentiug system
`designed in accordance with the present invention includin,
`a arrangement for converting light which is not directed into
`a first portion of the spatial light modulator by a first
`polarising beam splitting cube [o the opposite polarization
`and directing it into a second polariziu~; beam splitting cube
`associated with a second portion of the spatial liglrt modu-
`lator;
`
`[U032] FIG. 181-C are diagrtuiunatic views of an elev-
`euthembodiment of a nuniaturized image generating system
`designed in accordance with the present invention; and
`
`[0033] FIG. 19 is a diagranuuatic side view of a portion
`of ~ miniariirized linage generating system illustrating 1
`plurality of li;ht sources of three different colors, a colli-
`matin~ lens, and a polarizing beam splitting cube tuned to a
`first one of the du-ee different colors of light, and in which
`the light sources of the other two colors are positioned to
`cooperate with the collimating lens to direct their light to the
`polv-izina beam splitting cube at angles which improve the
`efficiency at which the polarizing beam splitting cube acts
`upon the light of the two other colors.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`[0034] Turning to FI('.S. 2-18, wherein like components
`are designated by like reference ntunerals throughout the
`various Figures, attention is initially directed to FIG. 2.a.
`This Figure illustrates die general optical elements of an
`optical system, designed in accordance with the present
`invention, for an image gzneratiug system, or miniaturized
`assembly for producing modulated light, including a spatial
`light modtdator. In this case, die system is a miniature
`display system ,enerally indicated by reference numeral 26.
`As shown in FIG. 2~, a suitable and readily providable light
`source 28 is positioned away from a transmissive spatial
`light modulator 30 h<~ving an writing arrangement 32 for
`contmllin; the light modulating states of spatial light modu-
`lator 30. Writing u-ran~ement 32 may also switchably con-
`trol light source 28. Spatial light modulator 30 modulates
`light from light source 28 by selectively changing the
`polarization of the light passing through the spatial light
`modulator in response to data signal from writiu~ arrange-
`ment 32. A collimating ]ens 34 is positioned between light
`source 28 and spatial light modulator 30 and an eye piece
`lens 36 is positioned between spatial light modulator 30 and
`a source imaging area 38 such that suUstantially all of the
`light generated by light source 28 is directed through source
`imaging area 38 except for guy light which is specifically
`absorbed by or directed away from source imaging area 38
`by other optical elements positioned within the optical path
`between light source 28 and source imaguig area 38 such as,
`for example a polarizes 40 or an analyzer 41. Eyepiece lens
`36 having a focal length F2 is positioned one Focal length F2
`from spatial light modulator 30 and cooperates with light
`source 28, collimating lens 34, and spatial liglll modulator
`30 to form a real imane of light source 28 at source imaging
`area 38 such that a virtual image of'tlie pattern of modulated
`light from spatial limit modulator 30 is directly visible by a
`viewer From a viewing region 42. The real image of light
`source 2S is formed at source imajing area 38 because light
`source 28 is positioned a distance more th~ci F2, the £oc~l
`length of eyepiece lens 36, from eyepiece lens 36.
`
`IPR PAGE 14
`
`
`
`US 200610103913 Al
`
`May 18, 2006
`
`[0035] The above described arrangement illustrated in
`FIG. 2A lias the advantage over the prior art of directing
`nuich ;renter percentage of the light from light source 28
`Ylll'Otlah source imaging area 38 and into viewing region 42.
`This significantly reduces the power requirement Yi~r the
`light source since the wastage of light described above for
`the prior art arraugeinent is significantly reduced if not
`eliminated. Also, a system desinned in accordance with the
`present invention allows a wide variety of light sources to be
`used including ligkt sotu-ces which are suUstantially less
`expensive than the la be dithise light source 14 used in the
`prior art system. However, this particular arrangement
`shown in FIG. 2A substantially increases the overall len=th
`of the system and therefore is not practical when miniatur-
`izatiou of the over111 system is important.
`
`[0036] Referring now to FIG. 2B, an alternative basic
`configuration of an overall display system designed in
`accorduice with the present invention and generally deli
`Hated by reference munerai 44 will be described. Display
`system 44 includes light source 28, collimating lens 34,
`eyepiece lens 36, and source iinagin~ area 38 as describe
`above tier F'IG. 2A. However, in dais embodiment of tke
`present invention, 1 reflective type spatial light modtilator 4h
`controlled by writing arrangement 32 is used instead of a
`transmissive spatial light modulator.:As shown in FIG. 2S,
`a suitable and readily providable polarizing beam splitting
`cube 4A is positioned between spatial light modulator 46 and
`eyepiece lens 36. Also, light source 28 and collimating lens
`34 are positioned to one side of polarizing begun splitting
`cube 48.
`
`[0037] During die operation of basic display system 44
`described above. light from light source 28, indicated by
`lines 49, is collected by collimating lens 34 and directed into
`polarizing beam splitting cuUe 48. 11ie polarizing beam
`splitting cube reflects light of one polarization, for example
`S-polarized light, into spatial light modulator 46 and wastes
`light of the opposite polarization, for example P-polarized
`limit, allowing it to pass throu~ polarizing beam splitting
`cube 48. Spatial light modulator 46, controlled by writing
`arrangement 32, acts on the light of the one polarization
`(S-pol<lrized light) directed into the modulator by converting
`certain portions oP Qie light of the one polari~tion (S-po-
`larized light) to light of the opposite polarization (P-polar-
`ized light) forming an overall pattern of modulated light that
`is reflected back into polarizing beam splitting cube 48. "1'he
`polarizing bean splitting cube wastes li;lit of the one
`polarization (S-polarized light) by reflecting it back toward
`light source 2R and allows the converted light of the opposite
`polarisation (P-polarized light) to pass through polarizing
`beam splitting cube 48 into eyepiece lens 36 forming a real
`image of light source 28 at source imaging area 38. As
`described above, the real image of light source 28 is formed
`at source imaging area 38 because light source 28 is posi-
`tioned optically a distance greeter than one focal length oC
`eyepiece lens 36 from eyepiece lens 36. This arrangement
`also produces a vimial linage of the patteni of modulated
`light that is viewable from the source imaging area and
`viewing, region 42. One specific novel arrangement for
`spatial light modulator 46 and writing arrangement 32 is
`disclosed in iJ.S. Pat. Nn. 5,744,164.
`
`[0038] As illustrated by FIG. 2B, the above described
`arrangement, wkuch includes a rct3ectivc type spatial light
`modularor such as spatial light modulator 46, allows light
`
`source 28 to he moved away from spatial light modulator 4b
`without increasing flee front to back lena h of the overall
`system as was shown in FLG. 2A. This system, designed in
`accordance with die present invention, folds the optical path
`such that the portion of the optical path in winch light from
`the light source is directed into the spatial liar it modulaCor
`overlaps the portion of the optical path in which the light is
`directed tiom the spatial light modulator to the eyepiece
`lens. By overlapping the optical path as described, the sane
`physical space is used for both of these purposes and
`therefore the length of the system is not increased relative to
`the prior art system described above and shown in FLG. 1.
`Iu the embodiment illustrated in FIG. 2B, this folding of the
`optical path is accomplished by positioning poi~rizing beam
`splitting cube 48 in die space betwezn sp1ti11 light modu-
`lator 46 uid eyepiece 36. Again, this does not incr