(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2001/0013856A1
`HAMAKADA et al.
`(43) Pub. Date:
`Aug. 16, 2001
`
`US 2001 OO13856A1
`
`(54) VIDEO DISPLAY APPARATUS AND
`METHOD OF PREVENTING INADVERTENT
`SWITCH-OFF OF LIGHT SOURCE THEREN
`(76) Inventors: KUNIO HAMAKADA, SAITAMA
`(JP); GENICHIRO KUBOJI, TOKYO
`(JP); NOBOUO HASEGAWA,
`TOKYO (JP), OSAMU SUGIYAMA,
`TOKYO (JP); HARUNA MASUOKA,
`KANAGAWA (JP); RYUICHI YODA,
`KANAGAWA (JP); SHIGEKI OHNO,
`GIFU (JP)
`Correspondence Address:
`JAY H MAIOLI
`COOPER AND DUNHAM
`1185 AVENUE OF THE AMERICAS
`NEW YORK, NY 10036
`Notice:
`This is a publication of a continued pros
`ecution application (CPA) filed under 37
`CFR 1.53(d).
`(21) Appl. No.:
`09/169,298
`(22) Filed:
`Oct. 9, 1998
`
`(*)
`
`
`
`(30)
`
`Foreign Application Priority Data
`
`Oct. 14, 1997 (JP)........................................ PO9-28O3O2
`
`Publication Classification
`
`(51) Int. Cl." ....................................................... G09G 5/00
`(52) U.S. Cl. .............................................................. 345/156
`
`(57)
`
`ABSTRACT
`
`A video display apparatus comprising a Video display device
`for Visually presenting a video image thereon, a light Source
`turned on by discharge and displaying the Video image,
`which is being presented Visually on the Video display
`device, on a Screen by irradiation of light; and a System
`controller for putting out the light Source after a lapse of a
`predetermined delay time from input of a command to
`Switch off a power source. There is also provided a method
`of preventing inadvertent Switch-off of the light Source in
`Such a video display apparatus. Even if the power Source is
`Switched off inadvertently, the light Source is not put out at
`once and the video image can Still be displayed continuously
`thereon by Switching on a power key immediately within the
`predetermined delay time.
`
`VIZIO, Inc. Exhibit 1018
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 1 of 11
`
`

`

`Patent Application Publication Aug. 16, 2001 Sheet 1 of 4
`
`US 2001/0013856A1
`
`F G.
`
`
`
`VIZIO, Inc. Exhibit 1018
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 2 of 11
`
`

`

`Patent Application Publication Aug. 16, 2001 Sheet 2 of 4
`F G 2
`
`US 2001/001.3856A1
`
`5
`
`S
`
`2
`
`F G 4
`
`S1
`
`
`
`
`
`MUTE WIDEO AND
`AUDIO OUTPUTS
`
`S2
`
`WAT FOR 5 SECONDS
`(DELAY TIME)
`
`S3
`
`TURN OFF LAMP-S4
`
`
`
`VIZIO, Inc. Exhibit 1018
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 3 of 11
`
`

`

`Patent Application Publication Aug. 16,2001 Sheet 3 of 4
`
`US 2001/0013856 Al
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`VIZIO,Inc. Exhibit 1018
`VIZIO,Inc. v. Maxell, LTD, IPR2022-01459
`Page 4 of 11
`
`VIZIO, Inc. Exhibit 1018
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 4 of 11
`
`
`
`
`

`

`Patent Application Publication Aug. 16, 2001 Sheet 4 of 4
`
`US 2001/0013856A1
`
`F G5
`
`(POWER ON)-S 11
`S12
`
`OFF
`
`S3 CANCEL WIDEO
`AND AUDIO MUTE
`
`S4
`
`
`
`3 O SECONDS
`ELAPSED AFTER
`AME, OFE
`
`s
`
`END
`
`NO
`
`WAITE FOR
`
`30 SECONDS
`
`TURN ON LAMP - S6
`
`CANCEL WIDEO
`AND AUDIO MUTE
`
`S 17
`
`VIZIO, Inc. Exhibit 1018
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 5 of 11
`
`

`

`US 2001/OO13856A1
`
`Aug. 16, 2001
`
`VIDEO DISPLAY APPARATUS AND METHOD OF
`PREVENTING INADVERTENT SWITCH-OFF OF
`LIGHT SOURCE THEREN
`
`BACKGROUND OF THE INVENTION
`0001) 1. Field of the Invention
`0002 The present invention relates to improvements in a
`Video display apparatuS Such as a television receiver, a
`monitor or a Video projector, and also in a method of
`preventing inadvertent Switch-off of a light Source in Such a
`Video display apparatus.
`0003 2. Description of the Related Art
`0004. In the category of video display apparatus (also
`termed Video projection apparatus), there are included a
`television receiver, a Video monitor and a Video projector as
`described.
`0005. In any of the video display apparatus mentioned, a
`Video image is visually presented on a video display device
`Such as a liquid crystal display unit for example, and then the
`Video image is enlarged and displayed on a Screen with
`projection of outgoing light of a light Source from behind the
`liquid crystal display unit.
`0006 For example, a liquid crystal rear projection tele
`Vision receiver employing a liquid crystal display unit is
`adapted for achieving a wider Screen with reduction of its
`depth, So that a larger-sized Screen is easily realizable as
`compared with an ordinary television receiver employing a
`cathode-ray tube.
`0007. A light source used in such a video display appa
`ratus consists of a lamp which utilizes discharge. In a lamp
`of this type, a gas is enclosed between electrodes and is
`caused to emit light by discharge between the electrodes. In
`case a power Source for this lamp is in an off-state, the gas
`between the electrodes of the lamp is dispersed uniformly.
`And when the power Source is Switched on to energize the
`lamp, a high AC Voltage is applied thereto, whereby the gas
`is ionized between the electrodes to Start emission of light.
`And thereafter the gas is placed in a steady State of emission
`as the high Voltage is lowered.
`0008 However, there may occur a case where, in a lamp
`of this type, the gas is not ionized properly despite appli
`cation of a high AC voltage and consequently fails to emit
`light. In this State, it is necessary, for lighting the lamp again,
`to once Switch off the power Source for the lamp and then to
`wait awhile until the inter-electrode gas is dispersed uni
`formly.
`0009 No problem arises if a user completely switches off
`the power Source for the lamp intentionally before going to
`bed or going out. But if the user inadvertently turns off the
`lamp while watching television on the Video display appa
`ratus by carelessly touching a power key of a remote
`controller for example, the lamp cannot be turned on imme
`diately as described even if the user tries to light up the lamp
`by Switching on the power key again, and consequently the
`user needs to wait for 30 Seconds or So until next lighting of
`the lamp. Thus, there exists a problem of Serious inconve
`nience in use.
`
`SUMMARY OF THE INVENTION
`0010. It is therefore an object of the present invention to
`provide a Video display apparatus where, despite inadvertent
`
`Switch-off of a power Source, a light Source turned on by
`discharge is not put out at once and Video images can Still be
`displayed continuously thereon by Switching on a power key
`immediately.
`0011 And another object of the present invention is to
`provide a method of preventing inadvertent Switch-off of a
`light Source in Such a video display apparatus.
`0012. According to an aspect of the present invention,
`there is provided a Video display apparatus which comprises
`a Video display device for Visually presenting a Video image
`thereon, a light Source turned on by discharge and displaying
`the Video image, which is being presented Visually on the
`Video display device, on a Screen by irradiation of light; and
`a System controller for putting out the light Source after a
`lapse of a predetermined delay time from input of a com
`mand to Switch off a power Source.
`0013 And according to another aspect of the present
`invention, there is provided a method of preventing inad
`vertent Switch-off of a light Source in Such a video display
`apparatus, wherein, when a Video image is being presented
`Visually on the Video display device, the light Source is
`turned on and lighted by discharge, So that the Video image
`on the Video display device is displayed on the Screen by the
`light Source. In this case, the System controller functions to
`put out the light Source after a lapse of a predetermined delay
`time from Switch-off of the power source.
`0014 Consequently, when the power source is switched
`off, the light Source is not put out at once and then is turned
`off after a lapse of a predetermined delay time. Therefore,
`even if a user of the Video display apparatus inadvertently
`Switches off the power Source in error, the light Source being
`lighted by discharge is held in its on-state when the power
`Source is Switched on immediately, So that the Video display
`State can be maintained continuously to attain remarkable
`convenience in use.
`0015. In the present invention, both video and audio
`outputs are muted by the System controller in response to
`Switch-off of the power Source, and the light Source is put out
`after a lapse of the delay time from Switch-off of the power
`Source. Thus, in case the user inadvertently Switches off the
`power Source in error, the Video and audio outputs are
`muted, and therefore the user is enabled to immediately
`discern Such erroneous unintentional Switch-off of the power
`Source. Accordingly, if the user Switches on the power
`Source again upon Such discernment, it becomes possible to
`eliminate inadvertent turn-off of the light Source being
`lighted by discharge.
`0016. The above and other features and advantages of the
`present invention will become apparent from the following
`description which will be given with reference to the illus
`trative accompanying drawings.
`BRIEF DESCRIPTION OF THE DRAWINGS
`0017 FIG. 1 is a perspective view of an embodiment
`representing a Video display apparatus of the present inven
`tion;
`0018 FIG. 2 is a perspective view showing an exemplary
`internal Structure of the Video display apparatus in FIG. 1;
`0019 FIG. 3 shows exemplary internal circuits of the
`video display apparatus in FIG. 1 inclusive of a system
`controller, a lamp, a Screen and So forth;
`
`VIZIO, Inc. Exhibit 1018
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 6 of 11
`
`

`

`US 2001/OO13856A1
`
`Aug. 16, 2001
`
`0020 FIG. 4 is a flowchart showing a processing routine
`executed in response to Switch-off of a power Source by a
`user; and
`0021
`FIG. 5 is a flowchart showing another processing
`routine executed in response to Switch-on of the power
`Source by the user.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENT
`0022 Hereinafter a preferred embodiment of the present
`invention will be described in detail with reference to the
`accompanying drawings.
`0023. Since the following embodiment is a preferred
`example of the invention, a variety of technically desirable
`restrictions are incidental thereto. However, the Scope of the
`invention is not limited to Such embodiment alone unless
`otherwise Specified in the following description relative to
`any particular limitation of the invention.
`0024 FIG. 1 is a perspective view of a preferred embodi
`ment representing a Video display apparatus of the present
`invention. This diagram illustrates a rear projector termed a
`liquid crystal rear projection television receiver.
`0.025 The rear projector 1 has an upper cabinet 2 and a
`lower cabinet 3.
`0026. In the upper cabinet 2, a rectangular frame 4 is
`formed on its front, and a Screen 5 is attached to the frame
`4.
`0027. The upper cabinet 2 is shaped into a box with a top
`wall 6, Side walls 7, 8, a back wall 9 and a bottom wall 10,
`and has an internal cavity with an enclosed periphery. And
`a mirror 11 shown in FIG. 2 is disposed in the upper cabinet
`2. The Screen 5 Serving as a display plane is disposed on the
`front of the mirror 11. The mirror 11 is positioned obliquely
`at a predetermined angle to the Screen 5.
`0028. The lower cabinet 3 in FIG. 1 houses a projector 12
`and other devices therein in addition to the screen 5 and the
`mirror 11. On the front of the lower cabinet 3, there are
`disposed speakers 13, 13, a manipulator 15, an error display
`16 and so forth. The manipulator 15 has a plurality of
`manipulation buttons 15a. And the error display 16 has a
`plurality of, e.g., light emitting diodes (LED) 16A, 16B, 16C
`and so forth.
`0029. The rear projector 1 is equipped with a wireless
`remote controller 20.
`0030 FIG. 3 shows an exemplary internal structure of
`the upper cabinet 2 and the lower cabinet 3 in FIG. 1.
`0031. The lower cabinet 3 houses a projector 12, which
`has a liquid crystal display device 30 corresponding to R
`(red), G (green) and B (blue). This liquid crystal display
`device 30 serves as a video display unit for visually pre
`senting video images, and a prism 99 and a lens system 100
`are interposed between the liquid crystal display device 30
`and the screen 5. The prism 99 composites the images
`presented respectively on a liquid crystal panel 30A for R
`(red), a liquid crystal panel 30B for G (green) and a liquid
`crystal panel 30C for B (blue) of the liquid crystal display
`device 30, and then the lens system 100 enlarges the
`composite image and projects the same onto the Screen 5. In
`this case, the composite video image on the liquid crystal
`
`display device 30 is displayed in an enlarged size on the
`screen 5 through projection thereto with irradiation of the
`light from a lamp 24 which Serves as a light Source in the
`lower cabinet 3 mentioned later.
`0032. Next, an exemplary circuit configuration housed in
`the lower cabinet 3 of FIG. 1 will be described below with
`reference to FIG. 3.
`0033. In FIG. 3, the rear projector 1 has the following
`circuit configuration.
`0034. The configuration of FIG. 3 comprises signal
`inputs 90,91, a signal processor 92 and a system controller
`60. The system controller 60 is connected electrically to the
`signal input 90 and the signal processor 92. The system
`controller 60 is further connected electrically to a lamp 24 as
`a light Source, a fan 25, a temperature Sensor 26 and a power
`Source PS.
`0035) The signal input 90 has a DVD (digital video disc
`or digital versatile disc) input 90A, a high definition televi
`sion signal (HD) input 90B, an AV (audio-visual) multiinput
`90C, a U/V antenna 45a, a BS antenna 46 and a video input
`90D. The signal input 91 has a signal sensor 20O to receive,
`e.g., an infrared input signal from a remote controller 20, and
`a manipulator 15.
`0036) The U/V antenna 45a is connected to a U/V tuner
`45b. Similarly, the BSantenna 46 is connected to a BS tuner
`47.
`0037. The signal processor 92 has an A/V switch 48, an
`audio control 49, speakers 13, 13, a 3-D comb filter 51, a
`wide ID signal detector 52, an extension TV 53, a chroma
`decoder 54, a scan converter 55, an RGB matrix 56, a white
`balancer 57, an LCD driver 58, a memory 61 and an image
`display IC (integrated circuit) 62.
`0038. The system controller 60 consists of a system
`microcomputer for example and is connected electrically to
`the aforementioned U/V tuner 45b, BS tuner 47, A/V switch
`48, wide ID signal detector 52, 3-D comb filter 51, extension
`TV 53, chroma decoder 54, scan converter 55, RGB matrix
`56, white balancer 57, driver 58, memory 61, audio control
`49 and image display IC 62 via a bus 400.
`0039. The sensor 20O and the manipulator 15 of the
`signal input 91 are connected to the system controller 60.
`The LEDs 16A-16C of the error display 16 shown in FIGS.
`1 and 3 are mutually combined for display in accordance
`with a command from the system controller 60.
`0040. The U/V tuner 45b selects a desired station out of
`terrestrial wave signals received by the U/V antenna 45a,
`and the BS tuner 47 selects a desired station out of Satellite
`broadcast signals received by the BS antenna 46.
`0041) The A/V switch 48 inputs video signals (V) and
`audio signals (L, R) obtained through the U/V tuner 45b and
`the BS tuner 47 and demodulated thereafter, and also video
`Signals (V) and audio signals (L, R) obtained from the video
`input 90D, and then outputs one selected signal.
`0042. The audio control 49 controls the left and right
`audio signals (L, R) selected by the A/V switch 48 and then
`emits the audio signals from the left and right Speakers 13,
`13.
`
`VIZIO, Inc. Exhibit 1018
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 7 of 11
`
`

`

`US 2001/OO13856A1
`
`Aug. 16, 2001
`
`0043. The video signal obtained from the HD input 90B
`and recorded on a hard disk is supplied to the RGB matrix
`56, while the audio signal is supplied to the A/V switch 48.
`The video signal from the AV multi input 90C is supplied to
`a color difference converter 77, while a Y (luminance)/color
`difference Signal is Supplied to the Scan converter 55, and the
`audio signal is supplied to the A/V switch 48.
`0044) The A/V switch 48 selects the input signal and then
`outputs the video signal to the 3-D comb filter 51.
`0045. The 3-D comb filter 51 inputs the video signal
`selected by the A/V Switch 48 and, after separating the video
`Signal into a luminance Signal and a color signal (Y/C),
`outputs the same therefrom.
`0046) The wide ID signal detector 52 detects, out of the
`video signal selected by the A/V Switch 48, the wide ID
`Signal Superimposed in the vertical blanking interval.
`0047. The extension TV 53 detects an extension televi
`Sion ID control Signal and decodes a reinforced signal out of
`the luminance Signal and the color Signal extracted through
`the 3-D comb filter 51, and then outputs such signals to the
`chroma decoder 54.
`0.048. The chroma decoder 54 demodulates the lumi
`nance signal and the color Signal of the Video signal obtained
`by decoding the ID control Signal and the reinforced signal
`in the extension TV 53, thereby obtaining demodulated
`Y/color difference signal.
`0049. The scan converter 55 converts the Y/color differ
`ence Signal into double speed signal Since the Signals
`demodulated in the chroma decoder 54 are not Suited for
`interlaced Scanning in the use of the liquid crystal display
`device 30, and further executes Zooming for example by
`converting the aspect ratio of the image display from 4:3 to
`16:9.
`0050. The RGB matrix 56 converts the double-speed
`Y/color difference Signal outputted from the Scan converter
`55 into double-speed RGB signal and Switches the same
`with the video signal obtained from the HD input 90B, and
`further inputs the screen display RGB signal obtained from
`the image display IC 62 and then Superimposes the same on
`the video RGB signal.
`0051) The white balancer 57 executes white balance
`adjustment of the RGB signal speed-doubled by the scan
`converter 55 and Superimposed by the RGB matrix 56.
`0052. The LCD driver 58 supplies the double-speed RGB
`Signal processed through white balance adjustment by the
`white balancer 57 to three LCD panels 57A, 57B, 57C to
`control the Same.
`0053) On the screen 5, there are visually presented the
`three LCD panels 57A, 57B, 57C for R, G, B and also the
`Video image having passed therethrough with the light
`irradiated from the lamp 24.
`0.054 The entire component elements of the apparatus are
`under control of the system controller 60 via the bus 400,
`and the System controller 60 executes various control actions
`in accordance with channel Select information inputted
`thereto via the bus 400 from the remote controller 20 or the
`manipulator 15 operated by the user.
`
`0055. In the memory 61 connected to the bus 400, there
`are stored data required for the system controller 60 to
`execute its various control actions. For example, Such data
`include those relative to desired picture mode, channel, input
`Switching and Sound Volume Specified by the user, and also
`data for adjustment of picture distortion and So forth.
`0056 Meanwhile the system controller 60 executes
`on/off control of the lamp 24, the fan 25 and the LEDs 16A,
`16B, 16C of the error display 16.
`0057 The system controller 60 controls an error detec
`tion mechanism provided for detecting any abnormal error
`State relative to the filter, fan, lamp and temperature.
`0058. The error detection mechanism actuated by the
`System controller 60 detects various error States and also
`performs other operations of Switching off the power Source
`and So forth upon detection of any abnormal error State and
`executes required display corresponding to each error State.
`0059 Display of each abnormal error state is represented
`by a combination of the three LEDs 16A, 16B, 16C of the
`error display 16 provided on the front of the liquid crystal
`projection television 1. Normally, these LEDs 16A, 16B,
`16C Serve to display the current State of the power Source.
`For example, the power LED 16A is turned on when the
`power source is switched on. The standby LED 16B is
`turned on when the Set power Source is in a Standby mode.
`And the BSpower LED 16C is turned on when the BS power
`Source is Switched on. Any individual error State is displayed
`by means of such LEDs 16A, 16B, 16C.
`0060. The system controller 60 instructs the image dis
`play IC 62 via the bus 400 to output the image display RGB
`Signal, thereby executing Superimposed display and So forth
`on the Screen 5 shown in FIGS. 1 and 2.
`0061 Now an explanation will be given on various
`abnormal error states with reference to FIG. 3.
`0062) The lamp 24 is a type caused to emit light by
`discharge as will be described later. Since heat is generated
`in this lamp 24 with emission of light, it is necessary to cool
`the lamp 24 by means of the fan 25.
`0063. In case the lamp 24 is abnormal, there may occur
`a trouble that the lamp fails to be turned on because of its
`Structure where emission of light is caused by discharge. In
`another case, the lamp 24 may not be lighted any longer due
`to expiration of its Service life. A lamp error detection Signal
`LES is sent from the lamp 24 to the system controller 60,
`whereby an off-state of the lamp 24 is detected.
`0064. As the lamp 24 has a service life, the apparatus is
`So constructed as to enable the user to open the cover and
`replace the lamp 24 with a new one upon expiration of its
`service life. When the cover of the lamp 24 is opened for
`replacement of its unit inclusive of the lamp 24 itself, a cover
`error detection signal CES for the lamp 24 is sensed to detect
`that the cover is open.
`0065. A fan error detection signal FES is sensed to detect
`any improper rotation of the fan 25 when the fan 25 fails to
`be rotated properly for Some reason.
`0066. A filter error detection signal FS is used in the
`following case. The fan 25 serves to cool the unit of the lamp
`24 while sending air thereto, but when some dirt or dust is
`Sent into this unit together with air, it causes malfunction of
`
`VIZIO, Inc. Exhibit 1018
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 8 of 11
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`

`US 2001/OO13856A1
`
`Aug. 16, 2001
`
`the lamp 24. For the purpose of avoiding Such trouble, a
`filter is employed to eliminate any dirt or dust. However, dirt
`or dust is gradually accumulated on the filter with a lapse of
`time to consequently deteriorate passage of air. It is therefore
`necessary to remove the accumulated dirt or dust after taking
`off the filter. The filter error detection signal FS is sensed to
`detect that the filter has been taken off.
`0067. A temperature error detection signal TES is used in
`the following case. Even if the fan 25 keeps cooling the unit,
`there still exists a possibility that the temperature in the unit
`rises to be abnormally high. Such condition is derived from
`abnormal generation of heat in the lamp 24 or from insuf
`ficient cooling by the fan 25. In this case, a temperature error
`detection signal TES is sent to the system controller 60 so
`that the abnormally high temperature in the unit can be
`detected.
`0068. In addition to the above, a fan rotation signal FAS
`is sent from the system controller 60 to the fan 25 so as to
`rotate the fan 25 at a predetermined rate. And a lamp lighting
`signal LS is sent from the system controller 60 to the lamp
`24 So as to turn on the lamp 24.
`0069. Next, an explanation will be given on the lamp 24.
`A gas is enclosed between electrodes of the lamp 24 con
`Sisting of a high-intensity lamp or the like, and the gas emits
`light as a result of inter-electrode discharge.
`0070 If the system controller 60 does not send a lamp
`lighting Signal LS to the power Source PS for the lamp, the
`power source PS is Switched off, and the gas between the
`electrodes is dispersed uniformly in such off-state of the
`power source PS. The operation for turning on the lamp 24
`is started in response to a lamp lighting Signal LS from the
`system controller 60, and a high AC voltage of +25 kV is
`applied. Then the gas is ionized between the electrodes So
`that the lamp 24 begins emission of light. And when the high
`AC voltage is Subsequently lowered to a predetermined
`value, the lamp 24 is placed in a steady State of light
`emission.
`0071 At this time, there may occur a case where the gas
`fails to be ionized properly and therefore emits no light
`despite application of a high AC voltage of +25 kV. This
`abnormal State represented by a lamp error detection signal
`LES of FIG. 3 is inputted to the system controller 60. In this
`case, the system controller 60 waits for awhile without
`Sending the lamp lighting Signal LS to the lamp 24, because
`the operation for turning on the lamp 24 cannot be restarted
`until the inter-electrode gas in the lamp 24 is dispersed
`uniformly.
`0072) If any AC interruption happens during the on-state
`of the lamp 24, there may occur a case where the high AC
`Voltage that causes discharge between the electrodes is
`lowered to consequently turn off the lamp 24. In this
`condition, a lamp error detection signal LES is inputted to
`the system controller 60. At this time also, the system
`controller 60 waits for awhile without sending a lamp
`lighting Signal LS to the power Source PS because the
`operation for turning on the lamp 24 again cannot be started
`until the inter-electrode gas is dispersed uniformly.
`0073. As for the waiting time required to achieve uniform
`dispersion of the inter-electrode gas, 30 Seconds are neces
`Sary after the power Source is Switched off during the
`on-State of the lamp 24. In case the operation for turning on
`
`the lamp 24 again fails to be started, a time of 15 Seconds or
`So is required until turning on the lamp 24 again, Since the
`gas is still being ionized halfway.
`0074. No problem arises in case the user Switches off the
`power Source intentionally before going to bed or going out
`for example. However, if the user depresses the power key
`20A of the remote controller 20 inadvertently while watch
`ing television on the screen 5 of the rear projector 1 in FIG.
`1, it is possible for the user to prevent unintentional turn-off
`of the lamp 24 by depressing again the power key 20A of the
`remote controller 20 in the following manner, whereby the
`television on the screen 5 can still be watched continuously.
`0075) The liquid crystal panels 57A, 57B and 57C shown
`in FIG. 3 relative to R (red), G (green) and B (blue)
`respectively are disposed opposite to a compositing element
`Such as a prism. Video images formed on the liquid crystal
`panels 57A, 57B, 57C of the liquid crystal display device
`(video display device) are composited by the prism 99,
`which Serves as a compositing element, due to the light
`emitted from the lamp 24 disposed behind, and then are
`displayed on the Screen 5 after being enlarged by a magni
`fying lens 100.
`0.076
`Referring now to FIGS. 4 and 5, an explanation
`will be given on the operations performed in response to
`turning on and turning off the power Source.
`0.077
`First, FIG. 4 will be referred to. This flowchart
`shows an exemplary case where the user has depressed the
`power key 20A of the remote controller 20 in the rear
`projector 1 before going to bed or going out, or the user has
`depressed inadvertently the power key 20A of the remote
`controller 20 while watching television on the screen 5.
`0078. At step S1 of FIG. 4 where the user depresses the
`power key 20A of the remote controller 20 in FIG. 3, the
`sensor 20O senses such depression of the power key 20Aso
`that the system controller 60 recognizes Switch-off of the
`power source. Subsequently the system controller 60 sends
`a signal to the audio control 49 to mute (interrupt) the audio
`output from the Speaker 13 while Sending another signal to
`the image display IC 62 to mute (interrupt) the video output
`(step S2).
`007.9
`Thereafter at step S3, the system controller 60
`waits for a predetermined delay time of, e.g., 5 Seconds and
`then Stops Sending a lamp lighting Signal LS to the power
`Source PS, whereby the lamp 24 is turned off as shown at
`step S4.
`0080 Thus, when the user Switches off the power source
`intentionally at the time of going to bed or going out for
`example, the processes at steps S1-S4 of FIG. 4 are executed
`to mute both Video and audio outputs, and emission of light
`from the lamp 24 is brought to a halt after a lapse of the
`predetermined delay time.
`0081. At step S11 of FIG. 5 where the power key 20A is
`depressed to Switch on the power Source, the System con
`troller 60 recognizes that the power source has been
`Switched on by the depression of the power key 20A in the
`remote controller 20. Subsequently at step S12, the system
`controller 60 makes a decision as to whether the lamp 24 is
`in its on-state or not, on the basis that a lamp lighting Signal
`LS is sent to the power source PS and that a lamp error
`detection signal LES is not sent from the lamp 24. If the
`
`VIZIO, Inc. Exhibit 1018
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 9 of 11
`
`

`

`US 2001/OO13856A1
`
`Aug. 16, 2001
`
`result of the decision at step S12 signifies that the lamp 24
`is in its on-state, the operation proceeds to Step S13, where
`the System controller 60 sends a signal to the audio control
`49 and the image display IC 62 to thereby cancel both the
`Video mute (picture mute) and the audio mute. Conse
`quently, the audio output is emitted from the Speakers 13,
`while the video output is projected onto the screen 5.
`0082 If the result of the decision at step S12 signifies that
`the lamp 24 is in its off-State, the operation proceeds to Step
`S14, where the system controller 60 makes a decision as to
`whether a predetermined delay time of, e.g., 30 Seconds has
`elapsed or not after the lamp 24 is turned off. And if the
`result of the decision at step S14 signifies no elapse of 30
`seconds, the system controller 60 waits at step S15 until
`elapse of the delay time of 30 seconds.
`0.083. After elapse of 30 seconds at step S15 or in case the
`result of the decision at step S14 signifies that 30 seconds
`have already elapsed, the operation proceeds to Step S16,
`where the System controller 60 sends a lamp lighting Signal
`LS to the power source PS to thereby turn on the lamp 24.
`And thereafter at step S17, the system controller 60 sends a
`signal to both the audio control 49 and the image display IC
`62 to cancel both the video mute and the audio mute.
`0084. At steps S1-S3 in FIG. 4, as described above, the
`operation waits for a predetermined delay time of, e.g., 5
`Seconds after Video mute and audio mute are executed in
`response to Switch-off of the power Source by the user, So
`that it becomes possible to prevent Simultaneous turn-off of
`the lamp 24 with Such Switch-off of the power Source.
`Therefore, at the time point after wait for 5 seconds from
`Switch-off of the power source, the lamp 24 is turned off
`unless the user depresses the power key 20A of the remote
`controller 20 again to Switch it on, and then Supply of a lamp
`lighting Signal LS is brought to a halt at Step S4 to turn off
`the lamp 24.
`0085 Thus, even in case the user inadvertently depresses
`the power key 20A of the remote controller 20 while
`watching television on the Screen 5, both Video mute and
`audio mute are executed immediately So that the user can
`notice his erroneous unintentional depression of the power
`key 20A. Therefore, if the user immediately switches on the
`power key 20A again from the off-state within a lapse of 5
`Seconds, the System controller 60 keepS Sending the lamp
`lighting Signal LS continuously to the power Source PS,
`hence preventing a phenomenon that the lamp 24 is put out.
`0.086. In this manner, if the power key 20A in its off
`position is Switched on again by the user, both the Video
`mute and the audio mute can be canceled and the lamp 24
`is still kept in the on-state without being put out, So that the
`Video image can be projected onto the Screen 5. Thus, if the
`user manipulates